OBJECTIVES: To explore HtrA1 gene expression and its regulation in human gastric cancers. METHODS: The HtrA1 mRNA levels were examined by QPCR analysis and confirmed its expression with Northern blot analysis. The HtrA1 protein levels in all six gastric epithelial cell lines wer
e investigated by Western blot analysis. Gene copy number was accessed and then sequenced the coding region from each mRNA in all six cell lines. The HtrA1 promoter region DNA methylation status was detected by using bisulfite sequencing analysis. Effect of decitabine and TSA on HTRA1 expression in gastric cancer cell line was determined by RTPCR. RESULTS: HIC analysis indicated that HtrA1 was highly expressed in normal epithelium, but dramatically down-regulated in gastric carcinoma tissues and variably expressed in tumor-adjacent tissues. HtrA1 gene expression was dramatically decreased in gastric carcinoma cells compared to non-tumorigenic counterparts. The HtrA1 gene loss in any of the 4 breast cancer cell lines was not detected. Total 14 CpGs in this region were all methylated in gastric cancer cells, whereas two normal cells, GES-1 and HFI-145, were having several unmethylated cytosines in this region. HtrA1 showed as ~Mr 44,000, Expression of HtrA1 protein was not observed in any of the four gastric cancer cell lines, BGC-823, MKN-45, SGC-7901and MKN-28. HtrA1 expression was observed in the HFI-145and GES-1 cell lines. CONCLUSIONS: The epigenetic silencing for HtrA1 gene expression could provide a possible strategy for re-activating HtrA1 gene expression in gastric cancer cells, thus facilitating further investigation of HtrA1's role in chemotherapy.
Altobelli E, etal., Oncol Rep. 2015 Aug;34(2):555-66. doi: 10.3892/or.2015.4016. Epub 2015 May 28.
HtrA1 appears to be involved in several physiological processes as well as in the pathogenesis of conditions such as Alzheimer's disease and osteoarthritis. It has also been hypothesized to play a role as a tumor suppressor. This manuscript reviews the current cancer-related HtrA1 research from the
methodological and clinical standpoints including studies regarding its potential role as a tumor marker and/or prognostic factor. PRISMA method was used for study selection. The articles thus collected were examined and selected by two independent reviewers; any disagreement was resolved by a methodologist. A laboratory researcher reviewed the methods and laboratory techniques. Fifteen studies met the inclusion criteria and concerned the following cancer sites: the nervous system, bladder, breast, esophagus, stomach, liver, endometrium, thyroid, ovaries, pleura, lung and skin. Most articles described in vivo studies using a morphological approach and immunohistochemistry, whereas protein expression was quantified as staining intensity scored by two raters. Often the results were not comparable due to the different rating scales and study design. Current research on HtrA1 does not conclusively support its role as a tumor suppressor.
HtrA1 is a serine protease homologue to the bacterial serine-protease HtrA, also known as DegP, a heat shock-induced envelope-associated serine protease. It has been shown that over-expression of HtrA1 in human cancer cells inhibits cell growth and proliferation in vitro and in vivo, thus, suggestin
g a possible role as a tumor suppressor. The expression of HtrA1 was investigated in depth by means of immunohistochemistry in a large group of human lung cancer specimens and corresponding lymph node metastases. Univariate analysis showed, that the only statistically significant correlation was found between the HtrA1 expression level detected in the primary tumors and in the lymph node metastases. This result was also confirmed when the analysis was restricted only to the cases where both the primary tumor and the autologous lymph node metastasis were available. Our data suggest that HtrA1 may be involved in lung cancer progression by targeting several molecular pathways.
Resistance to chemotherapy presents a serious challenge in the successful treatment of various cancers and is mainly responsible for mortality associated with disseminated cancers. Here we show that expression of HtrA1, which is frequently downregulated in ovarian cancer, influences tumor response t
o chemotherapy by modulating chemotherapy-induced cytotoxicity. Downregulation of HtrA1 attenuated cisplatin- and paclitaxel-induced cytotoxicity, while forced expression of HtrA1 enhanced cisplatin- and paclitaxel-induced cytotoxicity. HtrA1 expression was upregulated by both cisplatin and paclitaxel treatment. This upregulation resulted in limited autoproteolysis and activation of HtrA1. Active HtrA1 induces cell death in a serine protease-dependent manner. The potential role of HtrA1 as a predictive factor of clinical response to chemotherapy was assessed in both ovarian and gastric cancer patients receiving cisplatin-based regimens. Patients with ovarian or gastric tumors expressing higher levels of HtrA1 showed a higher response rate compared with those with lower levels of HtrA1 expression. These findings uncover what we believe to be a novel pathway by which serine protease HtrA1 mediates paclitaxel- and cisplatin-induced cytotoxicity and suggest that loss of HtrA1 in ovarian and gastric cancers may contribute to in vivo chemoresistance.
BACKGROUND: HtrA1, a serine protease, is down-regulated in various human solid tumors. Overexpression of HtrA1 in human cancer cells inhibits cell growth and proliferation in vitro and in vivo, suggesting its possible role as a tumor suppressor. METHODS: Immunohistochemistry was
used to determine the expression of HtrA1 in 50 hepatocellular carcinoma specimens and adjacent liver tissues. The correlation between the expression of HtrA1 and the clinico-pathologic data were analyzed. RESULTS: The levels of HtrA1 were lower in tumor tissues than in their adjacent liver tissues. Moreover, an inverse relationship was found between HtrA1 expression and the differentiation of hepatocellular carcinoma. Loss of HtrA1 was more frequently found in tumors in Edmondson grade III-IV, especially in those with venous invasion, compared to tumors in Edmondson grade I-II. Most importantly, patients with higher HtrA1 expression had a better survival rate. CONCLUSION: All these data suggest an important role of HtrA1 in hepatocellular carcinoma development and progression, which may be a new target for its treatment.
Mullany SA, etal., Clin Cancer Res. 2011 Feb 1;17(3):427-36. doi: 10.1158/1078-0432.CCR-09-3069. Epub 2010 Nov 23.
PURPOSE: The purpose of this study was to determine if loss of serine protease HtrA1 in endometrial cancer will promote the invasive potential of EC cell lines. EXPERIMENTAL DESIGN: Western blot analysis and immunohistochemistry methods were used to determine HtrA1 expression in
EC cell lines and primary tumors, respectively. Migration, invasion assays and in vivo xenograft experiment were performed to compare the extent of metastasis between HtrA1 expressing and HtrA1 knocked down clones. RESULTS: Western blot analysis of HtrA1 in 13 EC cell lines revealed complete loss of HtrA1 expression in all seven papillary serous EC cell lines. Downregulation of HtrA1 in Hec1A and Hec1B cell lines resulted in a three- to fourfold increase in the invasive potential. Exogenous expression of HtrA1 in Ark1 and Ark2 cells resulted in three- to fourfold decrease in both invasive and migration potential of these cells. There was an increased rate of metastasis to the lungs associated with HtrA1 downregulation in Hec1B cells compared to control cells with endogenous HtrA1 expression. Enhanced expression of HtrA1 in Ark2 cells resulted in significantly less tumor nodules metastasizing to the lungs compared to parental or protease deficient (SA mutant) Ark2 cells. Immunohistochemical analysis showed 57% (105/184) of primary EC tumors had low HtrA1 expression. The association of low HtrA1 expression with high-grade endometrioid tumors was statistically significant (P = 0.016). CONCLUSIONS: Collectively, these data indicate loss of HtrA1 may contribute to the aggressiveness and metastatic ability of endometrial tumors.
Kortvely E and Ueffing M, Adv Exp Med Biol. 2016;854:23-9. doi: 10.1007/978-3-319-17121-0_4.
Age-related macular degeneration (AMD) is a sight-threatening disorder of the central retina. Being the leading cause of visual impairment in senior citizens, it represents a major public health issue in developed countries. Genetic studies of AMD identified two major susceptibility loci on chromos
omes 1 and 10. The high-risk allele of the 10q26 locus encompasses three genes, PLEKHA1, ARMS2, and HTRA1 with high linkage disequilibrium and the individual contribution of the encoded proteins to disease etiology remains controversial. While PLEKHA1 and HTRA1 are highly conserved proteins, ARMS2 is only present in primates and can be detected by using RT-PCR. On the other hand, there is no unequivocal evidence for the existence of the encoded protein. However, it has been reported that risk haplotypes only affect the expression of ARMS2 (but not of HTRA1), making ARMS2 the best candidate for being the genuine AMD gene within this locus. Yet, homozygous carriers of a common haplotype carry a premature stop codon in the ARMS2 gene (R38X) and therefore lack ARMS2, but this variant is not associated with AMD. In this work we aimed at characterizing the diversity of transcripts originating from this locus, in order to find new hints on how to resolve this perplexing paradox. We found chimeric transcripts originating from the PLEKHA1 gene but ending in ARMS2. This finding may give a new explanation as to how variants in this locus contribute to AMD.
Oka C, etal., Development 2004 Mar;131(5):1041-53.
HtrA1, a member of the mammalian HtrA serine protease family, has a highly conserved protease domain followed by a PDZ domain. Because HtrA1 is a secretory protein and has another functional domain with homology to follistatin, we examined whether HtrA1 functions as an antagonist of Tgfbeta family p
roteins. During embryo development, mouse HtrA1 was expressed in specific areas where signaling by Tgfbeta family proteins plays important regulatory roles. The GST-pulldown assay showed that HtrA1 binds to a broad range of Tgfbeta family proteins, including Bmp4, Gdf5, Tgfbetas and activin. HtrA1 inhibited signaling by Bmp4, Bmp2, and Tgfbeta1 in C2C12 cells, presumably by preventing receptor activation. Experiments using a series of deletion mutants indicated that the binding activity of HtrA1 required the protease domain and a small linker region preceding it, and that inhibition of Tgfbeta signaling is dependent on the proteolytic activity of HtrA1. Misexpression of HtrA1 near the developing chick eye led to suppression of eye development that was indistinguishable from the effects of noggin. Taken together, these data indicate that HtrA1 protease is a novel inhibitor of Tgfbeta family members.
OBJECTIVE: To evaluate if adult-onset foveomacular vitelliform dystrophy (AOFVD) and butterfly-shaped pigment dystrophy (BSPD) are associated with risk single-nucleotide polymorphisms (SNPs) for age-related macular degeneration (AMD). METHODS: This was a tertiary referral center-based cross-section
al study including 35 consecutive patients with BSPD and AOFVD, 317 patients with AMD, and 159 unaffected individuals. Demographics, clinical information, and ophthalmic imaging studies were collected. Sequencing was performed for the peripherin/RDS and BEST1 genes, and genotyping was performed for SNPs in the genes for complement factor H (CFH) (rs1061170), HTRA1 (rs11200638), and complement component 3 (C3) (rs2231099). RESULTS: Adult-onset foveomacular vitelliform dystrophy and BSPD were diagnosed in 24 (68.6%) and 11 (31.4%) of the 35 patients, respectively. The mean (SD) age of patients with pattern dystrophy (PD) was 75.3 (10) years and median visual acuity was 0.7. Pattern dystrophy was associated with the HTRA1 risk allele compared with unaffected individuals (odds ratio, 1.72; 95% CI, 1.11-2.66; P = .03). The HTRA1 SNP showed similar prevalence in patients with AMD and PD. The CFH risk allele was significantly less common in patients with PD compared with patients with AMD (odds ratio, 0.47; 95% CI, 0.28-0.76; P = .002). No mutations in peripherin/RDS or BEST1 were detected. CONCLUSIONS: The AOFVD and BSPD phenotypes are associated with an HTRA1 risk SNP. These phenotypes often present in elderly individuals who do not carry peripherin/RDS gene mutations and are associated with retinal pigment epithelium alterations and increased risk for choroidal neovascularization. Further research is required to evaluate if AOFVD and BSPD phenotypes in aged individuals are associated with AMD.
Zhu F, etal., Biochem Biophys Res Commun. 2015 Nov 20;467(3):589-94. doi: 10.1016/j.bbrc.2015.09.105. Epub 2015 Sep 25.
BACKGROUND AND AIMS: Epithelial-mesenchymal transition (EMT) is involved in the development and progression of cancer. HtrA1 had been showed to play a modulatory role in metastasis of hepatocellular carcinoma (HCC). The relationship between HtrA1 and EMT in HCC was investigated in the pre
sent study. METHODS: The HtrA1 expression in human HCC tumor tissues and cells was determined by real-time PCR. SiRNA-HtrA1 and pcDNA-HtrA1 were respectively transfected into HepG2 and MHCC97H cells to observe their effects on cell migration and expression of EMT-associated markers Vimentin and E-cadherin. The relationship between HtrA1 and EMT in 60 HCC patients was also investigated. RESULTS: HtrA1 expression of tumor tissues was down-regulated with the increasing of number in lymph nodes metastasis in HCC patients. HtrA1 down-regulation led to the significant increase of cell migration, Vimentin expression and decrease of E-cadherin expression, while HtrA1 overexpression resulted in an opposite function. The HtrA1 expression was positively related to the E-cadherin level (R(2) = 0.5903, P < 0.001) and negatively correlated with Vimentin level (R(2) = 0.6067, P < 0.001) in tumor tissues of HCC, respectively. CONCLUSION: HtrA1 expression was closely related to EMT, which might be a potential mechanism underlying metastasis of HCC.
Baldi A, etal., Pharmacogenomics. 2008 Aug;9(8):1069-77. doi: 10.2217/14622416.9.8.1069.
AIMS: The objective of our study was to analyze the potential prognostic value of the expression of the serine protease HtrA1 and of EGFR in 70 malignant mesotheliomas. MATERIALS & METHODS: Immunohistochemistry was used to determine the expression of HtrA1 and EGFR. Univariate a
nd multivariate analyses were used to correlate expression of these molecular factors in combination with available clinicopathologic data to patient survival. RESULTS: A positive, statistically significant relationship has been recorded between HtrA1 expression level and survival (p < 0.0001). By contrast, a negative relationship has been identified between EGFR expression and survival (p = 0.02). Moreover, extension of the tumor (T) and involvement of lymph nodes (N) advanced status (p = 0.001 and 0.002, respectively), as well as the sarcomatoid histotype (p = 0.005), correlated significantly with poor survival. Finally, by a multivariate Cox regression analysis, the only immunohistochemical parameter that resulted to influence overall survival was HtrA1 (p = 0.0001). Interestingly, the prognostic value of HtrA1 expression was completely independent from EGFR expression (p < 0.0001). CONCLUSION: This is the first study of the relationship between HtrA1 expression and survival of mesothelioma patients. The data obtained strongly indicate the utilization of HtrA1 expression as a prognostic parameter for mesothelioma and suggest this serine protease as a possible molecular target for the treatment of malignant mesotheliomas.
BACKGROUND: The genetic cause of cerebral autosomal recessive arteriopathy with subcortical infarcts and leukoencephalopathy (CARASIL), which is characterized by ischemic, nonhypertensive, cerebral small-vessel disease with associated alopecia and spondylosis, is unclear. METHODS: <
/b>In five families with CARASIL, we carried out linkage analysis, fine mapping of the region implicated in the disease, and sequence analysis of a candidate gene. We also conducted functional analysis of wild-type and mutant gene products and measured the signaling by members of the transforming growth factor beta (TGF-beta) family and gene and protein expression in the small arteries in the cerebrum of two patients with CARASIL. RESULTS: We found linkage of the disease to the 2.4-Mb region on chromosome 10q, which contains the HtrA serine protease 1 (HTRA1) gene. HTRA1 is a serine protease that represses signaling by TGF-beta family members. Sequence analysis revealed two nonsense mutations and two missense mutations in HTRA1. The missense mutations and one of the nonsense mutations resulted in protein products that had comparatively low levels of protease activity and did not repress signaling by the TGF-beta family. The other nonsense mutation resulted in the loss of HTRA1 protein by nonsense-mediated decay of messenger RNA. Immunohistochemical analysis of the cerebral small arteries in affected persons showed increased expression of the extra domain-A region of fibronectin and versican in the thickened tunica intima and of TGF-beta1 in the tunica media. CONCLUSIONS: CARASIL is associated with mutations in the HTRA1 gene. Our findings indicate a link between repressed inhibition of signaling by the TGF-beta family and ischemic cerebral small-vessel disease, alopecia, and spondylosis.
Age-related macular degeneration (AMD) is a leading cause of vision loss and blindness in the elderly. The dry form is more common and accounts for about 85-90% of AMD patients in US, while Japanese AMD patients predominantly progress to wet-form or polypoidal choroidal vasculopathy (PCV). Recent s
tudies have shown HTRA1, a serine protease gene, as major risk factor for wet form AMD (De Wan et al., Science 2006). Furthermore, we reported that the Japanese typical wet form AMD patients showed significant association with ARMS2/HTRA1 (Goto, Akahori et al., JOBDI 2009). The purpose of this study is to elucidate the function of ARMS2/HTRA1 gene promoter in wet-form AMD patients. The promoter sequence experiment showed that a great number of AMD patients had specific indel mutation in 3.8 kb upstream of HTRA1 gene. 2-3-fold increase of promoter activity was observed in indel HTRA1 promoter compared to control sequence (Iejima et al., JBC 2015). Furthermore, we created transgenic mice ubiquitously overexpressing mouse HtrA1 using the chicken act in promoter, continuous induction of HtrA1 in vivo was shown to lead to CNV, similar to wet AMD patients (Nakayama, Iejima et al., IOVS 2014). These results suggest that human HTRA1 expression is enhanced by AMD specific indel mutation in the promoter region of HTRA1 gene, and this enhanced HTRA1 may be concerned with induce retinal neovasucularization.
OBJECTIVES: Expression of human HtrA1, HtrA2, HtrA3 and TGF-beta1 genes was examined in ovarian tissue specimens including 19 normal ovaries, 20 benign tumors, 7 borderline tumors, 44 cancers and 8 Krukenberg tumors. DESIGN AND METHODS: mRNA and protein levels were evaluated by semi-quantitative RT-
PCR and Western-blotting methods, respectively. RESULTS: A statistically significant decrease of HtrA1 and HtrA3 expression in ovarian tumors comparing to normal tissues was observed. A dramatic decrease of HtrA3 mRNA and protein levels in all tumor tissue groups, and a loss of HtrA3 protein in 30% malignant tumors were found. A significant decrease of HtrA1 mRNA, and of HtrA3 mRNA and protein in malignant tumors compared to benign tumors was revealed. HtrA2 expression in tumor tissues was slightly decreased. Expression of TGF-beta1 in tumor tissues was not significantly different compared to control tissues. CONCLUSIONS: Our results show downregulation of HtrA1 and HtrA3 genes' expression in different types of ovarian tumors and give additional evidence that these genes may function as tumor suppressors.
Yu Y, etal., World J Surg Oncol. 2012 Aug 30;10:179. doi: 10.1186/1477-7819-10-179.
BACKGROUND: The purposes of this study were to measure both the mRNA and protein expression levels of high-temperature requirement serine peptidase 1 (HtrA1) in human esophageal cancer tissues and their adjacent, comparatively normal esophageal tissues. METHODS: The expression l
evels of HtrA1 mRNA and protein in both tissue types were measured by semi-quantitative RT-PCR (reverse transcription-polymerase chain reaction) and Western blotting. The clinical and pathological correlation between HtrA1 expression levels and the occurrence and development of esophageal cancer was analyzed. RESULTS: The expression levels of HtrA1 mRNA and protein in esophageal carcinoma were significantly lower than the levels expressed in their adjacent normal esophageal tissue (p < 0.05). The more highly undifferentiated esophageal tumor cells expressed lower HtrA1 mRNA and protein expression levels (p < 0.05). Patients with tumors in early pathological stages (I-II) had significantly higher HtrA1 mRNA and protein expression levels than did patients with tumors in mid-to-late pathological stages (III-IV) (p < 0.05). Patients with positive lymph node metastasis had significantly lower HtrA1 mRNA and protein expression levels than did patients with lymph node-negative disease (p < 0.05). CONCLUSIONS: HtrA1 expression is associated with the occurrence and development of esophageal cancer.
Globus O, etal., Sci Rep. 2017 Dec 21;7(1):17995. doi: 10.1038/s41598-017-18203-2.
Different cancer types as well as many other diseases are caused by aberrant activation of the canonical Wnt signal transduction pathway, and it is especially implicated in the development and progression of colorectal cancer (CRC). The main effector protein of the canonical Wnt signaling cascade is
β-catenin, which binds to the T- cell factor/lymphoid enhancer factor (TCF/LEF) and triggers the activation of Wnt target genes. Here, we identify the serine protease High-Temperature Requirement A1 (HTRA1) as a novel component of the canonical Wnt pathway. We show that the HTRA1 protein inhibits the Wnt/β-catenin signaling, in both paracrine and autocrine manners, and affects the expression of several Wnt target genes. Moreover, HTRA1 forms a complex with β-catenin and reduces the proliferation rates of cells. Taken together, our findings indicate that HTRA1 functions as a novel suppressor of the canonical Wnt signaling pathway.
INTRODUCTION: HtrA1 (high temperature requirement A1) is a serine protease of the HtrA family. We have previously shown that the placenta expresses the highest level of HtrA1 mRNA compared to other tissues in the human. Others have reported that placental HtrA1 is significantly up-regulated in pree
clampsia (PE), a pregnancy-specific multi-systemic disorder associated with new onset hypertension and proteinuria. However, it is unclear how serum HtrA1 changes in a normal pregnancy and whether it is altered in PE pregnancies. METHODS: A sandwich ELISA highly specific to human HtrA1 and suitable for serum detection was developed and thoroughly validated. This assay was then applied to serum samples from different stages of normal pregnancy, as well as early-onset (<34 weeks) and late-onset (>34 weeks) PE pregnancies. RESULTS: Serum HtrA1 increased progressively with increasing gestation in normal pregnancies. However, this trend was perturbed in women with PE. Compared to respective gestation-age-matched normal pregnancies, HtrA1 serum levels were significantly increased in early-onset PE, but significantly reduced in late-onset PE. DISCUSSION: This is the first report to show a clear increase of HtrA1 in the maternal circulation during normal pregnancy, consistent with HtrA1 being highly expressed in the placenta. Importantly, this study identified that serum HtrA1 was altered differently in early-onset and late-onset PE pregnancies, highlighting the complex regulation of HtrA1 in the different subtypes. The significant increase of serum HtrA1 in early-onset PE suggests that it may be a potential biomarker for the diagnosis of early-onset PE at disease presentation.
Yao Y and Li N, Med Sci Monit. 2020 Mar 27;26:e921933. doi: 10.12659/MSM.921933.
BACKGROUND This study was performed to estimate the genetic effects of HtrA1 polymorphisms rs1049331 and rs11200638 on treatment response in stage III colon cancer patients receiving 5-FU-based chemotherapy. MATERIAL AND METHODS A total of 105 stage III colon cancer patients who received postoperati
ve 5-FU based adjuvant chemotherapy were included in our study. Chemotherapy was performed in 3 cycles for the patients. HtrA1 rs1049331 and rs11200638 polymorphisms were genotyped via polymerase chain reaction with sequencing method. The treatment response was estimated according to the RECIST guidelines. RESULTS The response rate of the eligible patients was 53.33%. For rs1049331, the presences of TT genotype and T allele indicted reduced chemotherapy sensitivity (adjusted TT: OR=1.736, 95%CI: 1.001-3.011, P=0.049; T: OR=1.801, 95%CI: 1.054-2.932, P=0.039). The rs11200638 polymorphism had no significant association with chemotherapy sensitivity in the study population (P>0.05 for all). CONCLUSIONS HtrA1 rs1049331 polymorphism, but not rs11200638 polymorphism, can influence individual sensitivity to 5-FU-based treatment in stage III colon cancer patients.
The HtrA family of serine proteases takes part in cellular stress response including heat shock, inflammation and cancer. Downregulation of human HtrA1 and HtrA3 genes has been reported in some cancers, including endometrial cancer (EC), suggesting a tumor-suppressor role for both genes. The mechan
ism of the HtrA function is not known, however, evidence exists showing that both HtrA1 and HtrA3 regulate biological processes by modulating TGF-beta signaling. In the presented study the expression of human HtrA1, HtrA2, HtrA3 and TGF-beta1 genes was examined in 124 endometrial tissue specimens including 88 cancers and 36 normal endometria. The expression of the tested genes was evaluated at mRNA and protein levels by semi-quantitative RT-PCR and western blotting methods, respectively. Our results showed significant decrease of HtrA1 and HtrA3 mRNA and protein levels in EC compared to normal tissues. The most dramatic decrease was found for HtrA3 at both mRNA and protein levels (3.2- and 5.6-fold, respectively). Moreover, the HtrA3 protein (short isoform) was not detected in 19% of the cancers, and its level decreased from the premenopausal to the postmenopausal group. The HtrA2 protein levels were significantly lower in EC tissues compared to normal tissues. We also found a significant increase of the TGF-beta1 protein level in EC as well as a significant negative correlation between HtrA1/2/3 and TGF-beta1 relative protein levels. Our results showing downregulation of HtrA1 and HtrA3 gene expression support previous studies suggesting a tumor suppressor role for these genes. Furthermore, our data suggest that HtrA2 may be involved in EC development as well as suggest the involvement of HtrA1, HtrA2 and HtrA3 in the inhibition of TGF-beta signaling in endometrial tissues.
Altobelli E, etal., Oncol Rep. 2017 Jul;38(1):418-426. doi: 10.3892/or.2017.5700. Epub 2017 Jun 6.
The association between inflammatory bowel disease (IBD) and colorectal cancer (CRC) is being increasingly investigated. HtrA1 overexpression inhibits cell growth and proliferation by influencing apoptosis, invasiveness and migration of tumour cells. In the present study, HtrA1 expression was analys
ed in 228 colon tissue samples from patients with CRC, adenoma with high-grade dysplasia (AHD), adenoma with low-grade dysplasia (ALD), ulcerative colitis of >10 year duration (UCL), ulcerative colitis of <5 year duration (UCS) and colonic diverticulitis (D), and was compared with its expression in normal colon tissues (NCTs) collected 5 cm from the CRC lesion and in healthy colon mucosa (HC), to establish whether HtrA1 can serve as a biomarker for these conditions. All tissue specimens came from Italian Caucasian subjects. The main finding of the present study was that HtrA1 expression was significantly reduced in CRC and UCL tissues compared with that observed in both NCT and HC samples and with tissues from the other patients. In particular, a similar HtrA1 expression was detected in the stromal compartment of UCL and CRC samples. In contrast, the HtrA1 level was significantly lower (p=0.0008) in UCL compared with UCS tissues, suggesting an inverse relationship between HtrA1 expression and ulcerative colitis duration. HtrA1 immunostaining in the stromal compartment of AHD and ALD tissues showed no differences compared with the HC tissues. No data are available on the immunohistochemical localization of HtrA1 in CRC or IBD. The present findings suggest that HtrA1 could serve as a marker to identify UCL patients at high risk of developing CRC.
Zhao Z, etal., Med Oncol. 2015 Apr;32(4):112. doi: 10.1007/s12032-015-0524-z. Epub 2015 Mar 12.
HtrA1, as serine protease lower expressed in various human solid tumors, can down-regulate cell growth and proliferation. In this study, we focus on whether overexpressed HtrA1 can inhibit the growth of gastric cancer in vitro. This study found the HtrA1 is lower expressed in gastric cancer tissue t
han in normal gastric tissue. When HtrA1 is highly expressing with recombinant plasmid in gastric cancer cell lines SGC-7901 and AGS, it weakened cell proliferation, invasion, and migration in vitro. These data suggested that HtrA1 as an inhibitor in gastric cancer cells resulted in anti-proliferation, reduced invasion, decreased migration, and suppressed growth and may be an effective molecular targets on gastric cancer treatment.
Verdura E, etal., Brain. 2015 Aug;138(Pt 8):2347-58. doi: 10.1093/brain/awv155. Epub 2015 Jun 10.
Cerebral small vessel disease represents a heterogeneous group of disorders leading to stroke and cognitive impairment. While most small vessel diseases appear sporadic and related to age and hypertension, several early-onset monogenic forms have also been reported. However, only a minority of patie
nts with familial small vessel disease carry mutations in one of known small vessel disease genes. We used whole exome sequencing to identify candidate genes in an autosomal dominant small vessel disease family in which known small vessel disease genes had been excluded, and subsequently screened all candidate genes in 201 unrelated probands with a familial small vessel disease of unknown aetiology, using high throughput multiplex polymerase chain reaction and next generation sequencing. A heterozygous HTRA1 variant (R166L), absent from 1000 Genomes and Exome Variant Server databases and predicted to be deleterious by in silico tools, was identified in all affected members of the index family. Ten probands of 201 additional unrelated and affected probands (4.97%) harboured a heterozygous HTRA1 mutation predicted to be damaging. There was a highly significant difference in the number of likely deleterious variants in cases compared to controls (P = 4.2 × 10(-6); odds ratio = 15.4; 95% confidence interval = 4.9-45.5), strongly suggesting causality. Seven of these variants were located within or close to the HTRA1 protease domain, three were in the N-terminal domain of unknown function and one in the C-terminal PDZ domain. In vitro activity analysis of HTRA1 mutants demonstrated a loss of function effect. Clinical features of this autosomal dominant small vessel disease differ from those of CARASIL and CADASIL by a later age of onset and the absence of the typical extraneurological features of CARASIL. They are similar to those of sporadic small vessel disease, except for their familial nature. Our data demonstrate that heterozygous HTRA1 mutations are an important cause of familial small vessel disease, and that screening of HTRA1 should be considered in all patients with a hereditary small vessel disease of unknown aetiology.
Bayrakli F, etal., Turk Neurosurg. 2014;24(1):67-9. doi: 10.5137/1019-5149.JTN.6226-12.1.
AIM: To show the mutation in HTRA1 gene in a patient suffering from CARASIL syndrome with degenerated spine as a component of the disease. MATERIAL AND METHODS: We identified a family that one of the members had CARASIL syndrome in eastern Turkey and collected v
enous blood from available persons. The HTRA1 gene sequenced in all family members. RESULTS: C to T transition at position 1108 (c.1108 C > T) in exon 6, causing stop codon formation (R370X) was seen in the HTRA1 gene in a homozygous state in the CARASIL patient whereas it was heterozygous in other healthy family members. CONCLUSION: We demonstrated homozygous c.1108 C > T mutation in the HTRA1 gene causing a very rare syndrome, especially in the non- Japanese population, called CARASIL. Patients with degenerated spine and progressive clinical symptoms must be evaluated or reevaluated for other central nervous system symptoms and signs to rule out other diseases or syndromes.
Cai B, etal., Neurol Sci. 2015 Aug;36(8):1387-91. doi: 10.1007/s10072-015-2121-5. Epub 2015 Mar 13.
Cerebral autosomal recessive arteriopathy with subcortical infarcts and leukoencephalopathy (CARASIL) is a rare hereditary cerebral artery disease. The HtrA serine protease 1 (HTRA1) gene has been identified as the causative gene of CARASIL. Here, we report a n
ovel mutation in the HTRA1 gene in a CARASIL pedigree and explore its pathogenesis at the protein level. Subcutaneous tissue biopsy and HTRA1 gene analysis were performed in a CARASIL patient, and HTRA1 and TGF-beta1 protein expression in subcutaneous tissue and cultured fibroblasts from the proband were detected by immunohistochemistry and western blotting. A 28-year-old male proband and his brother experienced recurrent stroke, hair loss and low back pain. Abnormalities in the proband were found in the elastic plate of subcutaneous small arteries, and a novel homozygous frameshift mutation (c.161_162insAG), leading to the formation of a stop codon 159 amino acids downstream of the insertion (p.Gly56Alafs*160) was detected. Reduced HTRA1 protein and increased TGF-beta1 expression were detected in subcutaneous tissue and in cultured fibroblasts. A frameshift mutation in the HTRA1 gene detected in a CARASIL pedigree resulted in reduced HTRA1 protein and increased TGF-beta1 expression, which may cause severe CARASIL and peripheral small arterial disease.
Chen Y, etal., J Int Med Res. 2013 Oct;41(5):1445-55. doi: 10.1177/0300060513480926. Epub 2013 Aug 20.
OBJECTIVE: Mutations in the high-temperature requirement A serine peptidase 1 (HTRA1) gene were studied in a Chinese family with cerebral autosomal recessive arteriopathy with subcortical infarcts and leukoencephalopathy (CARASIL). METHODS: Exons 1-9 of the ... (more)
n style='font-weight:700;'>HTRA1 gene were amplified and bidirectionally sequenced in a Chinese family with CARASIL. Mutation effects were analysed by three-dimensional modelling of the serine protease HTRA1 protein. RESULTS: The proband was found to be homozygous for a novel missense mutation (c.854 C > T) identified in exon 4 of the HTRA1 gene; the parents of the proband were heterozygous for the same missense mutation. This c.854 C > T mutation resulted in a change from proline to leucine (p.P285L) in serine protease HTRA1, and was absent in 260 control chromosomes. Three-dimensional models showed that the change from proline to leucine (p.P285L) could attenuate the hydrogen bond between S284 and S287 residues, which might affect function of serine protease HTRA1. CONCLUSION: Discovery of a novel missense mutation (c.854C>T) associated with CARASIL expands the known CARASIL-related mutations in HTRA1.
Hadley D, etal., Invest Ophthalmol Vis Sci. 2010 Apr;51(4):2191-6. doi: 10.1167/iovs.09-3798. Epub 2009 Nov 20.
Purpose. To determine the relationship of six genetic variants (rs10490924, rs3750848, del443ins54, rs3793917, rs11200638, and rs932275) localized to the ARMS2-HTRA1 region of chromosome 10, region q26, as risk factors for age-related macular degeneration (AMD)
, to define the haplotype structure of these six loci, and to confirm their genetic association with the disease. Methods. Caucasian patients (n = 482) were stratified into categories based on AREDS (Age-Related Eye Disease Study) grading criteria (groups 0 and 1 served as the control, groups 3 and 4 contained subjects with AMD, and group 2 was excluded from the analysis). The six genetic variants in the ARMS2-HTRA1 region were genotyped and analyzed both independently and as a joint haplotype for association in subjects with disease (n = 291) compared with the control (n = 191). Results. The six high-risk alleles all showed a statistically significant association with AMD (the most significant SNP was rs10490924 [P < or = 3.31 x 10(-5), OR = 1.86]; the least significant SNP was rs932275 [P < or = 9.15 x 10(-5), OR = 1.78]). Multimarker analysis revealed that all six markers were in strong linkage disequilibrium with each other, and the two major haplotypes that captured >98% of the genetic variation in the region were both significantly associated with the disease: One increased the risk of AMD and contained only risk alleles (P < or = 2.20 x 10(-5)), and the other haplotype decreased the risk of AMD and contained only wild-type alleles (P < or = 6.81 x 10(-5)). Furthermore, 36 individuals comprising both cases and controls were identified outside of these two major haplotypes, with at least one discordant marker. Conclusions. The results replicate the previously reported association between the high-risk alleles and AMD and independently confirm, for the first time, an association with AMD and the indel (del443ins54) polymorphism in a Caucasian population. Two major haplotypes that are associated with AMD and many minor novel haplotypes were identified. The novel haplotypes, identified from 36 cases and controls with discordant alleles spanning the ARMS2-HTRA1 region provide unique opportunities to gauge the relative phenotypic contributions of each of these genetic risk factors. With the identification of more discordant patients in the future, it may be possible to resolve the ongoing controversy as to which of the risk alleles and genes (ARMS2 vs. HTRA1) has the greatest impact on disease susceptibility. Future work should include the analysis of larger and more diverse populations, to further define the linkage structure of the region with a focus on phenotypic effects on AMD of the various haplotypes involving 10q26, as well as a functional analysis of the normal ARMS2 protein.
PURPOSE: The purpose of this study was to investigate whether the genetic risk factors of age-related macular degeneration (AMD) are associated with the development of choroidal neovascularization (CNV) in highly myopic eyes of elderly Japanese. METHODS: Highly myopic elderly Japanese patients with
and without CNV were genotyped for three AMD-associated single nucleotide polymorphisms (SNPs), namely rs10490924 (A69S) of ARMS2, rs11200638 of HTRA1, and rs1061170 (Y402H) of complement factor H (CFH), with the TaqMan SNP assay. One hundred and eighty-three unrelated highly myopic (axial lengths>26.00 mm or refractive errors>-6.0 diopters) Japanese patients with CNV who were >or=50 years of age (mean age+/-standard deviation of 62.7+/-6.3 years) and 170 highly myopic patients without CNV who were >or=50 years old (62.3+/-7.1 years) were studied. The differences in the genotypic distributions for the three SNPs between the two groups were tested with the Trend chi2 test, and logistic regression analyses were performed for age and gender adjustment. RESULTS: No significant difference was detected in the distribution of the three SNPs, rs10490924 (P>0.1), rs11200638 (P>0.1), and rs1061170 (P>0.5), between the two groups even after adjustments for age and gender differences. CONCLUSION: The genetic risk factors of AMD related to these SNPs do not contribute significantly to the development of CNV in a highly myopic elderly Japanese population.
Lee KY, etal., Invest Ophthalmol Vis Sci. 2008 Jun;49(6):2613-9. doi: 10.1167/iovs.07-0860.
PURPOSE: Polypoidal choroidal vasculopathy (PCV) is a major cause of serosanguinous maculopathy in Chinese patients with age-related macular degeneration (AMD). Variants in the CFH and HTRA1/LOC387715 genes are strongly associated with AMD in Caucasians and Chin
ese. Variants in the C2 and BF genes have been found to confer a significantly reduced risk of AMD. This study was undertaken to determine whether these associations occur in Chinese patients with PCV. METHODS: Patients of Chinese ethnicity with clinically and angiographically diagnosed PCV and normal control subjects were recruited from the Singapore National Eye Centre. Five single-nucleotide polymorphisms (SNPs) in the CFH gene, two each within the C2 and BF genes and two variants located in the LOC387715 and HTRA1 genes, were screened in all patients and control subjects. RESULTS: Seventy-two patients with PCV and 93 normal control subjects were studied. A significant association was noted with CFH variants rs3753394 and rs800292 among the PCV cases (P = 0.0015 and P = 0.0045, respectively). Individuals homozygous for the TT genotype of rs3753394 had a significantly higher risk (P = 0.0076) of PCV (OR = 4.29; 95% CI: 1.47-12.50) than those carrying a single copy of the T allele (P = 0.3210; OR = 1.69; 95% CI: 0.60-4.78), after adjustment for such risk factors as age and sex. The genotype frequencies of rs11200638 and rs10490924 in HTRA1 and LOC387715, respectively, were also found to be significantly different between patients with PCV and normal control subjects (P = 0.00032 and P = 0.003, respectively). The AA genotype of rs11200638 and TT genotype of rs10490924 conferred a 4.9-fold (95% CI: 1.85-12.95) and 4.89-fold (95% CI: 1.85-12.90) increased risk of PCV, respectively, after adjustment for age and sex. The Y402H variant of CFH (rs1061170) and the BF and C2 variants were not significantly different in patients and normal control subjects. CONCLUSIONS: The SNPs rs3753394 and rs800292 of CFH and rs11200638 of HTRA1 are significantly associated with the risk of PCV in Chinese patients.
Abbas RO and Azzazy HM, Ophthalmic Genet. 2013 Jan 30.
ABSTRACT Background: Age-related macular degeneration (AMD) is one of the leading causes of blindness in the elderly worldwide. Several single nucleotide polymorphisms (SNPs) have been linked to the risk of developing AMD. We aimed to examine the association between AMD and SNPs on CFH, ARMS2 and <
span style='font-weight:700;'>HTRA1 in Egyptians, a previously unstudied population. Materials and methods: Genomic DNA was extracted from 26 AMD patients and 20 controls. Genotyping was performed using PCR followed by allele-specific restriction digestion and direct sequencing. Results: CFH rs1061170 was significantly associated with AMD with the frequency of the risk C allele being 0.53 in patients and 0.17 in controls (p < 0.017). The odds ratio (OR) for the TC genotype was 5.5 (95% CI: 1.1-26.4) and for combined TC + CC genotypes was 8 (95% CI: 1.7-37.1). ARMS2 rs10490924 was also significantly associated with the risk allele T found at a frequency of 0.5 in AMD and 0.15 in controls (p < 0.017, chi(2) test). The OR for the TG genotype was 4.667 (95% CI: 1.2-18.4) and for combined TG + TT genotypes was 7 (95% CI: 1.8-26.5). HTRA1 rs11200638 also was significantly associated, with the risk allele A found at a frequency of 0.44 in patients and 0.17 in controls (p < 0.017, chi(2) test). OR for GA genotype was 5 (95% CI: 1.2-20.9) and for the combined GA + AA genotypes was 6 (95% CI: 1.4-24.7). Conclusions: Our data demonstrates significant association between AMD and rs1061170 on CFH, rs10490924 on ARMS2 and rs11200638 on HTRA1 in Egyptian patients. These findings are in agreement with previous findings in Caucasians.
PURPOSE: Genetic variants CFH and ARMS2/HTRA1 gene regions as well as high-sensitivity C-reactive protein (CRP) levels are related to age-related macular degeneration (AMD). We evaluated their independent and combined effects on risk of AMD, as well as their int
eractions. DESIGN: Case-control study. PARTICIPANTS: Subjects with AMD (n = 244) or no or minimal maculopathy (n = 209) in the Age Related Eye Disease Ancillary Study. METHODS: Risk factors, genotypes, and biomarkers were assessed by questionnaire, direct measurement, and analyses of blood specimens. The independent and joint effects of serum CRP and CFH (rs1061170) and ARMS2/HTRA1 (rs10490924) genotypes were assessed using logistic regression analyses, adjusting for age, gender, education, smoking, body mass index, and vitamin/mineral supplementation. MAIN OUTCOME MEASURES: We defined AMD as large drusen, geographic atrophy, or neovascular disease. RESULTS: Higher CRP levels were associated with a higher risk of AMD, controlling for genotype and demographic and behavioral risk factors, with odds ratio 2.6 for levels of 3.0 mg/L and above versus below 1.0 mg/L (95% confidence interval, 1.01-6.7). Single nucleotide polymorphisms (SNPs) in both genes were also independently associated with risk of AMD, controlling for the level of CRP and other factors. Presence of both highest level of CRP together with risk genotypes for both SNPs, conferred the highest risk of AMD (OR 5.4, 95% CI 1.4-21.1). CONCLUSIONS: High-sensitivity CRP and polymorphisms in the CFH and ARMS2/HTRA1 genes are independently associated with risk of AMD. Higher CRP level tends to confer a higher risk of AMD within most genotype groups.
Cruz-Gonzalez F, etal., Ophthalmic Genet. 2013 Mar 27.
ABSTRACT Purpose: Age-related macular degeneration (AMD) is the main cause of legal blindness in the western adult population. We investigated the association between SNPs located in CFH, ARMS2 and HTRA1 and AMD in Spanish patients. Patients and Methods: We obt
ained peripheral blood samples from 121 patients with a diagnosis of AMD (84 exudative and 37 atrophic) at the Department of Ophthalmology of the University Hospital of Salamanca. We took 91 subjects as a control group. We studied a single nucleotide polymorphism (SNP) in each patient for each of the genes associated with high susceptibility to developing AMD using Real-time PCR with TaqMan probes for CFH and ARMS2 polymorphisms and PCR-RFLP for HTRA1 polymorphism. Results: We observed a statistically significant difference between patients and controls in the distribution of CFH rs1410996 genotypes, patients homozygous for the C-allele have twice the risk of developing the disease (p = 0.010; OR = 2,176 (1.194-3.964)). The analysis of ARMS2 rs10490923 polymorphism also showed differences in allelic distribution between the case and control groups (p < 0.001). Carriers of the T-allele appear more frequently in the group of patients (p < 0.001; OR = 3.340 (1.848-6.060)). Our results also confirm significant differences in the distribution of HTRA1 rs112000638 polymorphism with an increased representation of the G-allele in the patient's group (p < 0.001; OR = 6.254(3.463-12.280)). Our study also indicates that TTGG ARMS2/HTRA1 (rs10490923/rs112000638) haplotype increases the risk of developing AMD by 9 times. Conclusions: Our results show that genotypes of ARMS2 (rs10490923), HTRA1 (rs112000638) and CFH (rs1410996) polymorphisms are related to an increased risk of suffering AMD in Spanish patients.
Wang W, etal., Mol Cancer. 2020 Sep 2;19(1):134. doi: 10.1186/s12943-020-01256-9.
BACKGROUND: Cisplatin is a first-line drug for the treatment of human non-small cell lung cancer (NSCLC); however, the majority of patients will develop drug resistance after treatment. In order to overcome cisplatin resistance, it is important to understand the mechanisms underlying the
resistance. METHODS: A gene microarray was used to screen for genes related to cisplatin resistance in NSCLC cell lines. Subsequently, the correlation between the HDAC, RXR and HtrA1 genes, in NSCLC, were verified using gene manipulation. Immunohistochemical staining was used to detect HDAC, RXR and HtrA1 expression in NSCLC specimens. Proliferation, migration and invasion assays were performed in vitro and in vivo to determine the role of the HDAC/RXR/HtrA1 signaling axis in cisplatin resistance, and luciferase reporter analysis and ChIP assays were performed to ascertain the mechanisms by which HDAC and RXR regulate the expression of HtrA1. Furthermore, in vitro and in vivo experiments were conducted in NSCLC cisplatin-resistant NSCLC to elucidate the effect of the low molecular weight compound, DW22, which targets the NSCLC cisplatin resistance HDAC/RXR/HtrA1 signaling pathway. RESULTS: HtrA1 was identified as a cisplatin resistance-related gene in NSCLC cells. The regulation of HtrA1 by HDAC and RXR significantly decreased the efficacy of cisplatin in NSCLC cells resistant to cisplatin. Immunohistochemistry results showed a negative relationship between HDAC1 and HtrA1, and a positive relationship between RXRα and HtrA1 in NSCLC patients' tissues. Notably, the expression of HDAC1 and HtrA1 can be considered as biomarkers for the efficacy of platinum-based drugs and prognosis in NSCLC patients. Mechanistically, the heterodimers of the nuclear receptor RXR, in combination with the enzyme, HDAC, regulate the transcription of HtrA1 in NSCLC cells. The rescue of HtrA1 expression by dual targeting of HDAC and RXR with the compound, DW22, significantly inhibited the proliferation, migration and invasion of NSCLC cells resistant to cisplatin, and induced NSCLC cell apoptosis. CONCLUSION: Our results indicate that HtrA1, a cisplatin resistance-related gene, is synergistically regulated by HDAC and RXR in NSCLC. Targeting the HDAC/RXR/HtrA1 signaling axis can rescue HtrA1 expression and reverse cisplatin resistance in NSCLC.
Andreoli MT, etal., Am J Ophthalmol. 2009 Dec;148(6):869-74. doi: 10.1016/j.ajo.2009.07.002. Epub 2009 Oct 1.
PURPOSE: To examine the interaction of genotypic variation of 16 single-nucleotide polymorphisms (SNP) in the complement factor H (CFH) and LOC387715/ARMS2/HTRA1 loci with clinical characteristics of age-related macular degeneration (AMD). DESIGN: Retrospective
cohort study. METHODS: Eighty-four patients with neovascular AMD were genotyped using direct sequencing or Sequenom iPLEX technology. The Fisher exact test, Cochran-Mantel-Haenszel statistics, and Mann-Whitney U test were used to assess the effect of each SNP with respect to the following phenotypic manifestations: age at diagnosis, gender, affected eye, study and fellow eye visual acuity at diagnosis and at last follow-up, study eye best acuity during follow-up, presence of large drusen and retinal pigment epithelium (RPE) hyperpigmentation in study and fellow eye, choroidal neovascularization (CNV) angiographic subtype (classic vs occult), CNV size, presence of wet AMD in fellow eye, presence of dry AMD in fellow eye, and smoking history. RESULTS: Only SNPs in the LOC387715/ARMS2/HTRA1 (10q26) region were associated with disease phenotypes. The polymorphisms rs10664316 and rs1049331 were associated with a decreased risk of poor visual acuity during follow-up and at diagnosis; rs2672598 and rs2293870 were associated with a decreased risk of RPE hyperpigmentation; rs10664316 was associated with a decreased risk of RPE hyperpigmentation with large drusen in the study eye, but an increased risk of large drusen in the fellow eye; rs11200638 was associated with an increased risk of larger CNV; rs10490924 and rs11200638 were associated with younger age of diagnosis. CONCLUSIONS: Several polymorphisms examined in the LOC387715/ARMS2/HTRA1 locus, but none in the CFH region, correlated with specific phenotypic attributes of AMD.
Emerging evidence has demonstrated that high-temperature requirement protein A1 (HtrA1) appears to be involved in several important biological processes in mammals such as growth, apoptosis, embryogenesis, invasion, metastasis, and cancer and has been verified to be reduced in a variety of human tum
ors. However, its precise functions and molecular mechanisms in esophageal squamous cell carcinoma (ESCC) remain unclear. Here, we detected HtrA1 level in ESCC tissues and cells and investigated the biological roles of HtrA1 in ESCC. We found that expressions of HtrA1 mRNA and protein in ESCC tissues and cells were significantly lower than those in normal esophageal epithelial tissues and cells (P < 0.05). Expressions of HtrA1 mRNA and protein were closely associated with TNM staging and lymph node metastasis (P < 0.05). Additionally, the survival rate of patients with low HtrA1 level was lower than those patients with high HtrA1 level (P < 0.05). Elevated HtrA1 level markedly inhibited cell proliferation in vitro and in vivo, reduced cell invasion in vitro, and induced cell apoptosis. Notably, HtrA1 overexpression inhibited phosphorylation levels of IκBα and p65 subunit of the NF-κB signaling pathway, but increased total IκBα level, coupled with decreases of Ki-67, Bcl-2, Bcl-xL, cyclin D1, and MMP-9 proteins and increase of caspase-3 activity. Overall, these data suggest that HtrA1 may play critical roles in the tumorgenesis and progression of ESCC, and HtrA1 overexpression exerts its anti-tumor effect by blocking the NF-κB signaling pathway; thus, manipulation of HtrA1 may be an effective molecular target for ESCC treatment.
Age-related macular degeneration (AMD) is a complex disorder with genetic and environmental influences. The genetic influences affecting AMD are not well understood and few genes have been consistently implicated and replicated for this disease. A polymorphism (rs11200638) in a transcription factor
binding site of the HTRA1 gene has been described, in previous reports, as being most significantly associated with AMD. In this paper, we investigate haplotype association and individual polymorphic association by genotyping additional variants in the AMD risk-associated region of chromosome 10q26. We demonstrate that rs11200638 in the promoter region and rs2293870 in exon 1 of HTRA1, are among the most significantly associated variants for advanced forms of AMD.
Zhang L, etal., J Biol Chem. 2012 Jan 6;287(2):1520-6. doi: 10.1074/jbc.M111.275990. Epub 2011 Nov 2.
Genome-wide association study (GWAS) has identified genetic variants in the promoter region of the high temperature requirement factor A1 (HTRA1) gene associated with age-related macular degeneration (AMD). As a secreted serine protease, HTRA1
:700;'>HTRA1 has been reported to interact with members of the transforming growth factor-beta (TGF-beta) family and regulate their signaling pathways. Growth differentiation factor 6 (GDF6), a member of the TGF-beta family, is involved in ectoderm patterning and eye development. Mutations in GDF6 have been associated with abnormal eye development that may result in microphthalmia and anophthalmia. In this report, we identified a single nucleotide polymorphism (SNP) rs6982567 A/G near the GDF6 gene that is significantly associated with AMD (p value = 3.54 x 10(-8)). We demonstrated that the GDF6 AMD risk allele (rs6982567 A) is associated with decreased expression of the GDF6 and increased expression of HTRA1. Similarly, the HTRA1 AMD risk allele (rs10490924 T) is associated with decreased GDF6 and increased HTRA1 expression. We observed decreased vascular development in the retina and significant up-regulation of GDF6 gene in the RPE layer, retinal and brain tissues in HTRA1 knock-out (htra1(-/-)) mice as compared with the wild-type counterparts. Furthermore, we showed enhanced SMAD signaling in htra1(-/-) mice. Our data suggests a critical role of HTRA1 in the regulation of angiogenesis via TGF-beta signaling and identified GDF6 as a novel disease gene for AMD.
Xiong Z, etal., Ann Clin Lab Sci. 2017 May;47(3):264-270.
The high temperature requirement factor A1 (HtrA1), a member of serine protease family, has been reported to be down-regulated in various cancer types and correlate with chemoresistance. However, the function of HtrA1 in colon cancer remains unclear. This study investigated the role of HtrA1 in cisp
latin (CDDP) resistance of colon cancer. We found that HtrA1 was up-regulated in colon cancer cell line SW480 incubated with CDDP. By treating SW480 cells to a continuous exposure to CDDP, we developed CDDP-resistant SW480/CDDP cells and found that the mRNA and protein levels of HtrA1 were reduced. Besides, the stable knock-down of HtrA1 in SW480 transfected with HtrA1 shRNA could also induce chemoresistance against CDDP. To the contrary, ectopic expression of HtrA1 in SW480/CDDP cells abrogated CDDP resistance. The mechanism underlying HtrA-1 down-regulation induced chemoresisance was also investigated. In SW480/CDDP cells and SW480 cells with HtrA1 knock-down, X-linked inhibitor of apoptosis protein (XIAP) was increased, while the interfering of XIAP impeded CDDP resistance in SW480/CDDP cells. We also found that Akt was activated in SW480/CDDP cells and SW480 cells with HtrA1 knock-down. The inhibition of Akt activation reversed CDDP resistance. In conclusion, our results indicate that HtrA1 down-regulation induces CDDP resistance in colon cancer by increasing XIAP and activating PI3K/Akt pathway. This study provides evidence that HtrA1 might be a therapeutic target for overcoming CDDP resistance in colon cancer.
Xu Y, etal., J Cell Biochem. 2014 Jun;115(6):1112-21. doi: 10.1002/jcb.24751.
Cisplatin (CDDP) resistance usually develops during lung adenocarcinoma (LAC) therapy. However, the comprehensive mechanisms remain largely unclear. In this study, we first established a CDDP-resistant LAC cell line-A549/CDDP from its parental cell line-A549. The results showed that CDDP resistance
in A549/CDDP cells correlates with acquirement of cancer stem cell-like properties (increased percentage of CD133-expressing subpopulation, sphere formation and levels of some pluripotency-associated markers). HtrA1 expression at both mRNA and protein levels was reduced in CDDP-resistant A549/CDDP cells compared with that in A549 cells. Ectopic expression of HtrA1 in A549/CDDP cells reversed cancer stem cell-like properties and CDDP resistance. In A549 cells, stable knockdown of HtrA1 expression promoted cancer stem cell-like properties and CDDP insensitivity, however, these effects were blocked by inhibition of PI3K/Akt pathway using LY294002. Furthermore, HtrA1 knockdown could significantly stimulate PI3K/Akt signaling in A549 cells. In vivo studies, HtrA1 knockdown promoted tumorigenesis and conferred CDDP resistance in xenograft A549 tumors, which were reversed by intraperitoneal injection of LY294002. In conclusion, these results indicate that HtrA1 downregulation confers CDDP resistance by inducing cancer stem cell-like properties via PI3K/Akt-dependent pathway in A549 cells. Therefore, HtrA1 may be a potential target for overcoming CDDP resistance in LAC.
Wu H, etal., Biochem Biophys Res Commun. 2019 Jun 30;514(3):933-939. doi: 10.1016/j.bbrc.2019.05.076. Epub 2019 May 11.
Cancer-associated fibroblasts comprise the major stromal cell populations in gastric cancer, which is a significant contributor to cancer-related death worldwide. As a member of the serine protease family, HTRA1 is reportedly involved in malignant transformation
of various tumor types. In the present study, we observed that HTRA1 is positively correlated with α-SMA expression in gastric cancer tissues, which was also confirmed by correlation analysis and Gene Set Enrichment Analysis (GSEA) using the GEO database. Upregulation of HTRA1 in gastric cancer cell lines induces expression of α-SMA in normal fibroblasts. To explore how HTRA1 activates normal fibroblasts, an ELISA assay was performed. Secretion of bFGF/FGF2 from gastric cancer cells was significantly increased in response to HTRA1 overexpression. However, upreguation of α-SMA in normal fibroblasts induced by HTRA1 was restored by inhibiting the expression of bFGF. Furthermore, HTRA1 promotes bFGF/FGF2 expression through activation of NF-κB signaling in gastric cancer cells. Inhibition of the NF-κB signaling pathway partially restored baseline expression levels of α-SMA induced by HTRA1. In conclusion, HTRA1 promotes transdifferentiation of normal fibroblasts to cancer-associated fibroblasts by increasing bFGF/FGF2 expression, which is dependent upon activation of NF-κB signaling in gastric cancer.
Cameron DJ, etal., Cell Cycle. 2007 May 2;6(9):1122-5. Epub 2007 May 16.
Age-related macular degeneration (AMD) is the most common cause of irreversible visual impairment in the developed world. The two forms of advanced AMD, geographic atrophy (GA) and choroidal neovascularization (wet AMD), represent two types of degenerative processes in the macula that lead to loss o
f central vision. Soft confluent drusen, characterized by deposits in macula without visual loss are considered a precursor of advanced AMD. A single nucleotide polymorphism, rs11200638, in the promoter of HTRA1 has been shown to increases the risk for wet AMD. However, its impact on soft confluent drusen and GA or the relationship between them is unclear. To better understand the role the HTRA1 polymorphism plays in AMD subtypes, we genotyped an expanded Utah population with 658 patients having advanced AMD or soft confluent drusen and 294 normal controls and found that the rs11200638 was significantly associated with GA. This association remains significant conditional on LOC387715 rs10490924. In addition, rs11200638 was significantly associated with soft confluent drusen, which are strongly immunolabeled with HTRA1 antibody in an AMD eye with GA similar to wet AMD. Two-locus analyses were performed for CFH Y402H variant at 1q31 and the HTRA1 polymorphism. Together CFH and HTRA1 risk variants increase the odds of having AMD by more than 40 times. These findings expand the role of HTRA1 in AMD. Understanding the underlying molecular mechanism will provide an important insight in pathogenesis of AMD.
AIMS: HtrA1 is a member of the HtrA (high-temperature requirement factor A) family of serine proteases. HtrA1 plays a protective role in various malignancies due to its tumour suppressive properties. The aim of this study was to determine HtrA1 expression as a predictor of chemoresponse i
n patients with advanced gastric cancer. METHODS AND RESULTS: HtrA1 expression was determined by immunohistochemistry on specimens of primary gastric cancer from 80 patients treated consecutively with cisplatin-based combination chemotherapy. Response to chemotherapy was assessed according to Response Evaluation Criteria in Solid Tumours (RECIST) criteria. Our population consisted of males/females [51/29; median age 64 years (range 32-82)]. A complete or partial response was observed in 71.4% [95% confidence interval (CI) 54.7-88.2], 66.7% (95% CI 47.8-85.5) and 28.6% (95 CI 11.8-45.3) of tumours showing high, medium and low HtrA1 expression, respectively. A statistically significant association between HtrA1 expression and the clinical response was observed (P = 0.002). The median overall survival for patients with high/medium expression was 17 months compared to 9.5 months for patients with low HtrA1 expression (P = 0.037). CONCLUSIONS: Identification of HtrA1 in gastric cancer prior to chemotherapy indicates that levels of HtrA1 could be used to predict response to platinum-based combination therapies. Further assessment of HtrA1 expression is highly warranted in large, prospective studies.
Jones A, etal., Proc Natl Acad Sci U S A. 2011 Aug 30;108(35):14578-83. doi: 10.1073/pnas.1102853108. Epub 2011 Aug 15.
Age-related macular degeneration (AMD) is the leading cause of irreversible blindness in the elderly. Wet AMD includes typical choroidal neovascularization (CNV) and polypoidal choroidal vasculopathy (PCV). The etiology and pathogenesis of CNV and PCV are not well understood. Genome-wide associatio
n studies have linked a multifunctional serine protease, HTRA1, to AMD. However, the precise role of HTRA1 in AMD remains elusive. By transgenically expressing human HTRA1 in mouse retinal pigment epithelium, we showed that increased HTRA1 induced cardinal features of PCV, including branching networks of choroidal vessels, polypoidal lesions, severe degeneration of the elastic laminae, and tunica media of choroidal vessels. In addition, HTRA1 mice displayed retinal pigment epithelium atrophy and photoreceptor degeneration. Senescent HTRA1 mice developed occult CNV, which likely resulted from the degradation of the elastic lamina of Bruch's membrane and up-regulation of VEGF. Our results indicate that increased HTRA1 is sufficient to cause PCV and is a significant risk factor for CNV.
Francis PJ, etal., Mol Vis. 2008 Aug 4;14:1395-400.
PURPOSE: To estimate the joint effects of single nucleotide polymorphisms (SNPs) in the genes complement factor H (CFH), HtrA serine peptidase 1 (HTRA1), and age-related maculopathy susceptibility 2 (LOC387715/ARMS2) in a Caucasian age related macular degenerat
ion (AMD) case-control cohort. METHODS: We genotyped three SNPs, rs1061170 (exon 9, CFH), rs11200638 (HTRA1 promoter, -512 bp), and rs10490924 (6.6 kb upstream of HTRA1 in LOC387715/ARMS2) in 333 cases with advanced AMD (choroidal neovascularization [CNV] and geographic atrophy) and 171 age-matched examined controls. Association tests were performed for individual SNPs and jointly with the CFH SNP Y402H. Analyses for interaction were also performed. RESULTS: The linkage disequilibrium measure for two SNPs on 10q26, rs10490924 and rs11200638, is D'=0.8 and all four possible haplotypes of the two SNPs were detected in the samples. The allelic association test for rs11200638 on the promoter of HTRA1 yielded p-values less than 10(-10) for geographic atrophy, less than 10(-16) for neovascularization, and less than 10(-19) for the pooled phenotypes (with an odds ration [OR] of 3.973; 95% confidence interval [CI] 2.928, 5.390). Disease risk is conferred in a dosage-dependent fashion. Similar figures were observed for the LOC387715/ARMS2 SNP. No interaction was detected between either between the 10q26 SNPs or the CFH SNP. CONCLUSIONS: This is the first analysis to show that the two 10q26 SNPs are not in complete linkage disequilibrium. Our studies however show that both the HTRA1 and LOC387715/ARMS2 SNP appear to contribute equally to disease risk (both geographic atrophy and choroidal neovascularization) with no evidence of interaction with CFH.
Grigaitė J, etal., Genes (Basel). 2021 Dec 7;12(12):1955. doi: 10.3390/genes12121955.
Biallelic mutations in the high-temperature requirement A serine peptidase 1 (HTRA1) gene are known to cause an extremely rare cerebral autosomal recessive arteriopathy with subcortical infarcts and leukoencephalopathy (CARASIL), which belongs to the group of he
reditary cerebral small vessel diseases and is mainly observed in the Japanese population. Even though this pathology is inherited in an autosomal recessive manner, recent studies have described symptomatic carriers with heterozygous HTRA1 mutations who have milder symptoms than patients with biallelic HTRA1 mutations. We present the case of a Lithuanian male patient who had a stroke at the age of 36, experienced several transient ischemic attacks, and developed an early onset, progressing dementia. These clinical symptoms were associated with extensive leukoencephalopathy, lacunar infarcts, and microbleeds based on brain magnetic resonance imaging (MRI). A novel heterozygous in-frame HTRA1 gene deletion (NM_002775.5:c.533_535del; NP_002766.1:p.(Lys178del)) was identified by next generation sequencing. The variant was consistent with the patient's phenotype, which could not be explained by alternative causes, appeared highly deleterious after in silico analysis, and was not reported in the medical literature or population databases to date.
Friedrich U, etal., Hum Mol Genet. 2015 Nov 15;24(22):6361-73. doi: 10.1093/hmg/ddv346. Epub 2015 Aug 26.
High-temperature requirement A1 (HTRA1) is a secreted serine protease reported to play a role in the development of several cancers and neurodegenerative diseases. Still, the mechanism underlying the disease processes largely remains undetermined. In age-related
macular degeneration (AMD), a common cause of vision impairment and blindness in industrialized societies, two synonymous polymorphisms (rs1049331:C>T, and rs2293870:G>T) in exon 1 of the HTRA1 gene were associated with a high risk to develop disease. Here, we show that the two polymorphisms result in a protein with altered thermophoretic properties upon heat-induced unfolding, trypsin accessibility and secretion behavior, suggesting unique structural features of the AMD-risk-associated HTRA1 protein. Applying MicroScale Thermophoresis and protease digestion analysis, we demonstrate direct binding and proteolysis of transforming growth factor beta1 (TGF-beta1) by normal HTRA1 but not the AMD-risk-associated isoform. As a consequence, both HTRA1 isoforms strongly differed in their ability to control TGF-beta mediated signaling, as revealed by reporter assays targeting the TGF-beta1-induced serpin peptidase inhibitor (SERPINE1, alias PAI-1) promoter. In addition, structurally altered HTRA1 led to an impaired autocrine TGF-beta signaling in microglia, as measured by a strong down-regulation of downstream effectors of the TGF-beta cascade such as phosphorylated SMAD2 and PAI-1 expression. Taken together, our findings demonstrate the effects of two synonymous HTRA1 variants on protein structure and protein interaction with TGF-beta1. As a consequence, this leads to an impairment of TGF-beta signaling and microglial regulation. Functional implications of the altered properties on AMD pathogenesis remain to be clarified.
Kaur I, etal., Invest Ophthalmol Vis Sci. 2008 May;49(5):1771-6. doi: 10.1167/iovs.07-0560.
PURPOSE: Single nucleotide polymorphisms (SNPs) in the LOC387715 (rs10490924), HTRA1 (rs11200638), and CFH (rs1061170) genes have been implicated in age-related macular degeneration (AMD). The present study was undertaken to determine the involvement of the LOC3
87715 and HTRA1 in an AMD cohort from India. METHODS: The coding region of LOC387715 (exon 1) and the promoter of HTRA1 were screened by resequencing in AMD cases and normal controls. Odds ratios were calculated to assess the risk of individual genotypes. Linkage disequilibrium (LD) and haplotype frequencies were estimated with Haploview software. Population attributable risk (PAR %) for the associated SNPs and their combined effects were calculated. RESULTS: Resequencing revealed seven different SNPs in these genes, of which significant associations were noted with the risk alleles of rs10490924 (T allele; P = 5.34 x 10(-12)) in LOC387715, and rs11200638 (A allele; P = 4.32 x 10(-12)) and rs2672598 (C allele; P = 3.39 x 10(-11)) in HTRA1 among the cases. Correspondingly, the homozygous risk genotypes TT, AA, and CC in these SNPs exhibited higher disease odds and PAR %. rs10490924 and rs11200638 were in tight LD (D', 0.90; 95% CI, 0.84-0.93). G-C-T-A-C was the risk haplotype (P = 8.04 x 10(-15)), whereas the G-C-G-G-T haplotype was protective (P = 2.01 x 10(-4)). The combined effect of the CFH (CC) and LOC387715 (TT) risk genotypes exhibited a PAR of 93.7% (OR, 73.89; 95% CI, 8.69-628.13). CONCLUSIONS: The present data provided an independent validation of the association of LOC387715 and HTRA1 SNPs, along with their risk estimates among Indian patients with AMD. These associations underscore their significant involvement in AMD susceptibility, which may be useful for predictive testing.