Positive Regulation Of Ovarian Cancer Cells By Rab25and Its Molecular Mechanism

Ovarian cancer is one of the three major gynecologic malignancies. Owing to the lacking of efficient early screening and diagnostic methods, the therapeutic effects and prognosis remain unsatisfactory in ovarian cancer. The understanding of molecular mechanism involved in the development and progression of ovarian cancer is the key to attain the effective diagnosis and treatment.Rab25is a small GTPase that regulates the vesicle transportation in cytoplasm. Some recent studies indicated that Rab25might be related to the initiation, progression and prognosis of various human ma-lignancies. Rab25has been reported to be an oncogene that induces the growth of neoplasm. Nevertheless, opposite results that Rab25suppress the cancer cells has been suggested by some researchers, which makes the exact role of Rab25in malignant neoplasm unclear. The effects of Rab25in malignancies are controversial, and the signal molecules and regulation mechanism of Rab25remain to be determined.The present study suppress the expression of Rab25by siRNA to explore its effects on the biologic behavior and signal transduction (proliferation, autophagy, apoptosis, and invasion) in two cell lines of ovarian cancer. The results showed:Rab25might induce the proliferation and invasion and suppress the programmed death of ovarian cancer cells, FSH up-regulate the expression of Rab25cells and thus partially suppress the autophagy and apoptosis in ovarian cancer cells, and the expression of Rab25is correlated with the clinical staging in pathologic specimen of ovarian cancer.Part Ⅰ. Rab25induces the proliferation and invasion and suppress the programmed death of ovarian cancer cellsObjective:To analyze the correlation between clinical staging of ovarian cancer and the expression of Rab25. To suppress the expression of Rab25by siRNA and explore its effects on the biologic behavior and signal transduction in ovarian cancer cells.Methods:The expression of Rab25in pathologic specimen was determined by tissue array and immunohistochemistry. The correlation between the expression level and clinical staging was analyzed by spearmen correlation. The expression of Rab25and phosphorylated ERK in ovarian cancer cells were detected by transfection of siRNA, real-time PCR, western blot, and immunofluororecent staining of cells. Cell pro-liferation was evaluated by SRB and cell cycles survey. Autophagy was observed by Acridine orange staining and the presence of pEGFP-LC3fluorescent particles. Apoptosis was detected by Annexin V-PI staining. Invasive ability was evaluated by transwell assay, enzymography, and actin fluororescent staining. Protein expression was measured by western blot.Results:1. The expression of Rab25is positively correlated with the clinical staging of ovarian cancer.2. Expression of Rab25was suppressed by its siRNA.3. The suppression of Rab25inhibited the proliferation of ovarian cancer cells.4. The suppression of Rab25promoted the programmed cell death of ovarian cancer cells through ERK1/2pathway.5. The suppression of Rab25lowered the invasive ability of ovarian cancer cells.Conclusion:The expression of Rab25is positively correlated with the clinical staging of ovarian cancer. Rab25might induce the proli-feration, suppress the autophagy and apoptosis, and enhance the invasive ability of ovarian cancer cells.Part Ⅱ. FHS up-regulate the expression of Rab25and thus partially suppress the autophagy and apoptosis in ovarian cancer cells.Objective:To explore the regulatory effects of FSH on Rab25Methods:Ovarian cancer cells were treated with FSH to observe the effect of FSH on the expression of Rab25. Cell proliferation was evaluated by SRB and cell cycles survey. Autophagy was observed by Acridine orange staining and the presence of pEGFP-LC3fluorescent particles. Apoptosis was detected by Annexin V-PI staining. Invasive ability was evaluated by transwell assay, enzymography, and actin fluororescent staining. Protein expression was measured by western blot.Results:1. FSH up-regulated the expression of Rab25in ovarian cancer cells.2. FSH inhibited the autophagy and apoptosis of ovarian cancer cells, and there was some interaction between FSH and Rab25.3. There was no interaction between FSH and Rab25in the promotion of pro-liferation and invasive ability of ovarian cancer cells.Conclusion:FSH up-regulated intracellular expression of Rab25in ovarian cancer cells. Rab25partially mediated the effects of FSH the autophagy and apoptosis of ovarian cancer cells. The promotion of growth, proliferation and invasive ability of ovarian cancer cells by FSH did not work through Rab25.