Abnormal Expression And Functions Of GMPS In Cervical Cancer

Cervical cancer is the most common gynecological malignancy and the fourth most common cause of cancer-associated mortality in women worldwide.GMPS(Guanine Monophosphate Synthase)has been reported to play multiple biological roles in tumor progression.Therefore,it is of great significance to explore the molecular mechanism of its role in the occurrence and progression of cervical cancer for the realization of targeted therapy.Objective:To explore the abnormal expression of GMPS in cervical cancer cell lines,cervical cancer tissues and adjacent tissues,and the effect and mechanism of targeted GMPS on cervical cancer cell proliferation,colony forming ability,radiochemotherapy sensitivity of cervical cancer cells.Methods:The differential expression of GMPS in cervical cancer tissues and para-carcinoma tissues was detected by qRT-PCR and immunohistochemistry;qRT-PCR and Western Blot were used to analyze the GMPS protein expression in four types of cervical cancer cell lines:HeLa,SiHa,C33A and CasKi;Using sirna-mediated RNAi technology to knock down the expression of GMPS in vitro;the effects of knockdown GMPS gene on the proliferation and cisplatin sensitivity of cervical cancer cells were detected by CCK-8;The ability of knockdown GMPS gene to clone cervical cancer cells was tested by plate cloning experiment;Western Blot was used to detect the expression levels of DNA damage and repair related proteins after GMPS knockdown,combined with cisplatin and radiotherapy,to explore the possible mechanism of its influence on radiochemotherapy sensitivity.Result:1.qRT-PCR results showed that the expression level of GMPS mRNA in cervical cancer tissues was significantly higher than that in adjacent tissues;2.In the mRNA expression levels of GMPS in cervical cancer cell lines HeLa,SiHa,C33A and CasKi cells,both HeLa and CasKi cells were highly expressed,while in the protein expression levels of GMPS,both HeLa and SiHa cells were highly expressed.Therefore,HeLa cells were selected as the main research cells;3.CCK-8 experiment showed that knockdown of GMPS could increase the proliferation of HeLa,SiHa,C33A and CasKi in cervical cancer cells,but had no significant effect on the cisplatin sensitivity of HeLa cells.4.Plate cloning experiment showed that knockdown of GMPS could inhibit the clonal formation ability of HeLa and C33A cells of cervical cancer cells;5.After the knockout of GMPS,the expression of yH2AX in HeLa cells increased slightly,while the expression of C33A and CasKi cells decreased;6.The expression of Rad51 in HeLa,C33A and CasKi cells was significantly increased after knockout of GMPS;7.Compared with the control group,the ATM/CHK2 pathway protein phosphorylation level in the GMPS knockout group was significantly increased;8.After GMPS knockdown of HeLa cells combined with radiotherapy X-ray(1Gy,2Gy,4Gy),immunoblot experiment results showed that protein phosphorylation levels of histone H2AX,Rad51 and ATM/CHK2 pathway in the experimental group were higher than those in the control group.Conclusion:GMPS in cervical cancer tissues abnormally high expression,targeted to knock on cell proliferation and clone formation after low GMPS has inhibitory effect,and can activate the DNA damage repair pathways Rad51 protein,ATM,CHK2.Targeted GMPS knockdown combined with radiotherapy can improve radiotherapy sensitivity,suggesting that GMPS may play an important role in the response to cervical cancer cell injury,and its influence on radiochemotherapy sensitivity still needs to be further explored.