Lin QH, etal., Cancer Sci. 2015 Oct;106(10):1463-73. doi: 10.1111/cas.12741. Epub 2015 Aug 10.
In a previous study, we found that ERGIC3 was a novel lung cancer-related gene by screening libraries of differentially expressed genes. In this study, we developed a new murine monoclonal antibody (mAb) against ERGIC3. This
avid antibody (6-C4) is well suited for immunohistochemistry, immunoblotting and solid-phase immunoassays. Furthermore, we systematically investigated expressions of ERGIC3 in a broad variety of normal human tissues and various types of tumors by immunohistochemistry. In normal human tissues, 6-C4 reacted only in some epithelial cells, such as hepatocytes, gastrointestinal epithelium, ducts and acini of the pancreas, proximal and distal tubules of the kidney, and mammary epithelial cells; however, most normal human tissues were not stained. Moreover, almost all carcinomas that originated from the epithelial cells were positive for 6-C4, whereas all sarcomas were negative. Notably, 6-C4 strongly stained non-small cell lung cancer (NSCLC) cells but did not react with normal lung tissues. Hence, ERGIC3 mAb could be used in histopathological diagnosis and cytopathological testing to detect early-stage NSCLC. We also studied the mechanisms of ERGIC3 regulation in vitro and in vivo by means of bioinformatics analysis, luciferase reporter assay, miRNA expression profiling and miRNA transfection. Results showed that miR-203a downregulation induced ERGIC3 overexpression in NSCLC cells.
Zhang LY, etal., J Biol Chem. 2013 Feb 8;288(6):4035-47. doi: 10.1074/jbc.M112.410506. Epub 2012 Dec 4.
MicroRNAs (miRNAs) are considered to be regulators of various biological processes in cancers, including the epithelial to mesenchymal transition (EMT), which is a key factor in cancer metastasis. In this study, we aimed to clarify the potential roles of miR-490-3p in hepatocellular carcinoma (HCC)
cells. Using real-time quantitative RT-PCR, we discovered that miR-490-3p was up-regulated in HCC tissues and cells compared with the adjacent non-tumor tissues and normal cells. We also found that overexpression of miR-490-3p led to an increase in cell proliferation, migration, and invasion abilities and that it contributed to EMT. The inhibition of miR-490-3p had the opposite effect on the cells. We identified ERGIC3 (endoplasmic reticulum-Golgi intermediate compartment protein 3) as a direct target gene for miR-490-3p. Unlike most miRNA-mRNA interactions, miR-490-3p increased ERGIC3 mRNA and protein levels as well as the intensity of expression of the EGFP reporter gene controlled by the 3'-UTR of ERGIC3 mRNA. The up-regulation by miR-490-3p also required the participation of Ago2. The inhibition of miR-490-3p reduced the expression of ERGIC3. Overexpression of ERGIC3 led to the same effect on HCC cells as miR-490-3p overexpression, including EMT. Importantly, silencing ERGIC3 reversed the cellular responses mediated by miR-490-3p overexpression. In conclusion, our study indicated for the first time that miR-490-3p functioned like an oncogenic miRNA in HCC cells and that the inhibition of miR-490-3p might provide an potential treatment approach for HCC patients.
Wu M, etal., BMC Cancer. 2013 Feb 1;13:44. doi: 10.1186/1471-2407-13-44.
BACKGROUND: To understand the carcinogenesis caused by accumulated genetic and epigenetic alterations and seek novel biomarkers for various cancers, studying differentially expressed genes between cancerous and normal tissues is crucial. In the study, two cDNA libraries of lung cancer wer
e constructed and screened for identification of differentially expressed genes. METHODS: Two cDNA libraries of differentially expressed genes were constructed using lung adenocarcinoma tissue and adjacent nonmalignant lung tissue by suppression subtractive hybridization. The data of the cDNA libraries were then analyzed and compared using bioinformatics analysis. Levels of mRNA and protein were measured by quantitative real-time polymerase chain reaction (q-RT-PCR) and western blot respectively, as well as expression and localization of proteins were determined by immunostaining. Gene functions were investigated using proliferation and migration assays after gene silencing and gene over-expression. RESULTS: Two libraries of differentially expressed genes were obtained. The forward-subtracted library (FSL) and the reverse-subtracted library (RSL) contained 177 and 59 genes, respectively. Bioinformatic analysis demonstrated that these genes were involved in a wide range of cellular functions. The vast majority of these genes were newly identified to be abnormally expressed in lung cancer. In the first stage of the screening for 16 genes, we compared lung cancer tissues with their adjacent non-malignant tissues at the mRNA level, and found six genes (ERGIC3, DDR1, HSP90B1, SDC1, RPSA, and LPCAT1) from the FSL were significantly up-regulated while two genes (GPX3 and TIMP3) from the RSL were significantly down-regulated (P < 0.05). The ERGIC3 protein was also over-expressed in lung cancer tissues and cultured cells, and expression of ERGIC3 was correlated with the differentiated degree and histological type of lung cancer. The up-regulation of ERGIC3 could promote cellular migration and proliferation in vitro. CONCLUSIONS: The two libraries of differentially expressed genes may provide the basis for new insights or clues for finding novel lung cancer-related genes; several genes were newly found in lung cancer with ERGIC3 seeming a novel lung cancer-related gene. ERGIC3 may play an active role in the development and progression of lung cancer.
