| 2314862 | KLK6 and KLK13 predict tumor recurrence in epithelial ovarian carcinoma. | White NM, etal., Br J Cancer. 2009 Oct 6;101(7):1107-13. | BACKGROUND: The human kallikrein-related peptidase family consists of 15 genes. Twelve of these genes are overexpressed in ovarian cancer and may represent potential markers for diagnosis, prognosis, and/or response to treatment. The aim of this study was to determine the prognostic significance of kallikrein-related peptidase 6 (KLK6) and kallikrein-related peptidase 13 (KLK13) in epithelial ovarian cancer by quantifying gene expression levels with tumour pathology and patient survival data. METHODS: Total RNA was isolated from 106 patients diagnosed with primary ovarian cancer, as well as 8 normal ovary controls. Samples were analysed by quantitative real-time PCR for KLK6 and KLK13 expression. Correlation between kallikrein gene expression and clinical characteristics was evaluated with the chi(2)-test. Survival analysis was performed using Kaplan-Meier and Cox proportional hazards regression models. RESULTS: Expression levels of both KLK6 and KLK13 mRNA were significantly increased in invasive cancers relative to normal ovaries (P=0.002 and 0.039 respectively). High KLK6 and KLK13 expression was an indicator of poor prognosis, with patients having a shorter recurrence-free survival (P=0.002 and 0.027 respectively). High KLK6 expression was also significantly associated with lower overall survival (P=0.011). When subjected to multivariate analysis, patients with either high KLK6 or KLK13 were 3- and 2.2-fold, respectively, more likely to have a recurrence than patients with low kallikrein expression. CONCLUSION: These data show increased mRNA expression of KLK6 and KLK13 in ovarian cancer compared to normal ovarian tissues. High KLK6 or KLK13 expression in primary ovarian tumours can significantly predict prognosis in terms of recurrence-free survival and overall survival. In all, this study shows KLK6 and KLK13 as potential biomarkers and may be therapeutic targets for treatment of ovarian cancer. | 19707197 | 2009-12-01 |
| 2314863 | [Expression of KLK6 protein and mRNA in primary breast cancer and its clinical significance.] | Wang SM, etal., Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi. 2008 Nov;24(11):1087-9. | AIM: To investigate the expression of KLK6 protein and mRNA in primary breast carcinoma, and to evaluate its clinical significance in clinicopathological status of patients with primary breast carcinoma. METHODS: 88 patients with primary breast carcinoma chosen randomly were examined for KLK6 protein and mRNA expression by SABC immunohistochemistry and RT-PCR, respectively. The association of KLK6 with the clinicopathologic features of the primary breast cancer was also analysis. RESULTS: The positive expression rates of KLK6 protein in breast carcinoma tissues were 78.40% (69/88). Clinicopathological parameters of breast carcinoma were associated with KLK6 protein expression. KLK6 protein was expressed less frequently in breast carcinoma tissues with lymph nodes metastasis (P<0.01) and ER(+) (P<0.05). Additionally, the mean expression level of KLK6 mRNA in cancerous tissues was significantly higher than that in normal tissues (P<0.01). However, KLK6 mRNA expression was negatively correlated with metastasis (P<0.01) and ER status (P<0.01). The expression of KLK6 protein and mRNA in primary breast carcinoma tissues was not associated with that of CerbB-2. CONCLUSION: KLK6 expression in cancerous tissues may play an important role in the invasion and metastasis of primary breast carcinoma. The detection of it along with clinical staging may help to predict the prognosis of patients with primary breast carcinoma. | 18992199 | 2008-12-01 |
| 1358604 | Decreased cerebrospinal fluid levels of neurosin (KLK6), an aging-related protease, as a possible new risk factor for Alzheimer's disease. | Mitsui S, etal., Ann N Y Acad Sci 2002 Nov;977:216-23. | Neurosin is a kallikrein-like serine protease expressed preferentially in the human brain. It is localized in senile plaques and neurofibrillary tangles in the brains of individuals with Alzheimer's disease (AD) and in Lewy bodies in patients with Parkinson's disease. Neurosin is present in the cere brospinal fluid (CSF) as a proenzyme and does not show any enzymatic activity. We have developed a sandwich ELISA system using monoclonal and polyclonal antibodies against human neurosin and have measured neurosin levels in the CSF from AD and non-CNS disease patients. Both male and female patients with peripheral neuropathy showed statistically positive correlations between CSF neurosin concentrations and age (males, n = 52, r = 0.482, p < 0.005; females, n = 43, r = 0.365, p < 0.005). In contrast, such positive correlation was not observed in the CSF from patients with AD. Further, some such patients showed extremely low levels of CSF neurosin. Our results suggest that neurosin is an aging-related protease and that a decreased CSF concentration of neurosin may be a risk factor for developing AD. | 12480753 | 2002-06-01 |
| 11077003 | Differences in Kallikrein-related peptidase mRNA sequences and KLK6 enzyme activity between mouse strains. | Murakami K, etal., Protein Pept Lett. 2014;22(3):204-11. | Several studies have reported differences in physiological and pathological phenotypes between different strains of experimental mice, such as environment-based behavior, skin damage, damage in response to toxins and nervous system injury. However, the mechanisms underlying these differences have no t yet been fully elucidated. We have been studying the function of kallikrein-related peptidases (KLKs), serine proteases known to serve a variety of functions. In this study, we focused on differences in KLKs between C57BL/6 mice and 129 mice. Among 13 KLKs genes examined, 12 KLKs showed differences in the mRNA coding region sequence and 7 KLKs showed different deduced amino acid sequences of their proteins when comparing C57BL/6 and 129 mice. KLK6 protein from 129 mice had six amino acid differences compared with that from C57BL/6 mice. KLK6 protein from 129 mice showed reduced SDS-PAGE mobility compared with that from C57BL/6 mice. Moreover, recombinant KLK6 protein from 129 mice had a higher optimum pH and >15 times higher hydrolytic enzymatic activity for several substrates than that from C57BL/6 mice. These results suggest that KLKs may contribute to the genetic basis of the differences between mouse strains. | 25666037 | 1000-05-01 |