The Proliferation Of Colon Cancer Cells Affected By RASSF1A Protein

Objective:This study aimed to investigate the expression of RASSF1A protein affect the proliferation of colon cancer cells and provide experiment data for reveal the development of colon cancer.Methods:The expression of RASSF1A protein was observed by Immunohistostaining in60cases colon cancer and40cases normal colonic mucous membrane tissues, and the clinical significance of RASSF1A protein expression was evaluated in different tissue. Then, we recombined the pCDNA3.1-RASSF1A eukaryotic expression vector by PCR. It was transfected into colon cancer SW480cells and selected by G418. Then, the SW480cells of stable expression RASSF1A were established. The cellulAr growth and proliferation of SW480cells were observed and detected by cellulAr growth curve, colony formation, and soft agar formation after stable expression of RASSF1A. The cycle and apoptosis of SW480-RASSF1A cells were analyzed by flow cytometry (FCM).Results:1.The immunohistostaining result exhibited that the positive expression rates of RASSF1A protein were95%(38/40) and46.7%(28/60) in normal colonic mucous membrane and colon cancer tissues. The positive expression rate of RASSF1A protein was obviously higher in normal colonic mucous membrane tissue than in colon cancer tissue (P＜0.01). The positive expression rates of RASSF1A protein were61.1%(22/36) and25%(6/24) in colon cancer tissue of Duke’s A+B stage and C+D stage; The positive expression rates of RASSF1A protein were11.1%(2/18) and61.9%(26/42) in colon cancer tissue of lymphaden metastasis and non-lymphaden metastasis. The expression of RASSF1A protein was re1Ated with Duke’s stage and lymphaden metastasis (P＜0.01).2. The experiment results of cellulAr growth curve, colony formation, and soft agar formation showed that, Compared with SW480and SW480-pCDNA3.1(+) cells, the growth velocity and reproductive activity of SW480-RASSF1A were obviously degraded, and the p1Ate formative colonies were smaller and fewer (62±26:208±36, P<0.01), and the soft agar formative colonies were smaller and fewer (76±38:472±64, P＜0.01).3. The result of flow cytometry (FCM) displAyed that, Compared with SW480and SW480-pCDNA3.1(+) cells, the proportion of SW480-RASSF1A cells in Gl period obviously increased and decreased in S period (P＜0.01), and the apoptosis rate of SW480-RASSF1A cells also significantly raised(P＜0.01).Conclusion:1. The expression of RASSF1was relevant with Duke’s stage and lymphaden metastasis.2. RASSF1A can induce the cycle arrest of Gl/S period and promote cellulAr apoptosis to inhibit the growth and proliferation of colon cancer SW480cells.