Effect And Mechanism Research Of ANXA3 On Colorectal Cancer Oxaliplatin Resistance

Objective: To investigate the effects of annexin a3 on colorectal cancer oxaliplatin drug resistance,and to observe the mechanism of ANXA3 in drug resistance.Methods:(1)HT-29/L-OHP cell line was established by stepwise selection in increasing dose of L-OHP.the expression levels of ANXA3 m RNA in HT-29 and HT-29/L-OHP cell lines were examined by RT-PCR and western blot respectively.(2)Using lipofectamine2000 to transfect ANXA3-si RNA into HT-29/L-OHP cells,and western blot detected silencing effect.(3)IC50 of L-OHP in HT-29 and HT-29/L-OHP cell lines was detected by CCK-8,CCK8 detected ANXA3 silencing HT-29/L-OHP cell drug sentivity.Western blot was used to detect the differential expression of HIF-1? in transfected cells and HT-29 cells.(4)The differential expression of HIF-1?and ANXA3 were detected by immune histochemical method in colorectal cancer tissues of responders and non-responder patients.Results:(1)The L-OHP resistance human colorectal cancer cell line HT-29/L-OHP was successfully established.the resistance index was 3.72.IC50 of L-OHP in HT-29 and HT-29/L-OHP cell lines was(4.921 ± 0.301)?g.ml-1 and(18.33 ± 0.596)?g.ml-1(p=0.003 <0.01).(2)The expression of protein level of ANXA3 in HT-29/L-OHP was higher than that of HT-29.There was a considerable rise of the expression of ANXA3 in non-responder patients of colorectal cancer as compared with responders.(3)It could be seen that there was a rapid growth in the drug-sensitivities of HT-29/L-OHP cells to oxaliplatin when the expression of the ANXA3 was down-regulated.the IC50 value for oxaliplatin in HT-29/L-OHP cells was(18.33 ± 0.596)?g.ml-1.ANXA3 ai RNA interference significantly increased oxaliplatin sensitivity in HT-29/L-OHP cell line and was accompanied by a considerable decrease in the IC50 value to(9.321±1.816)?g.ml-1(p=0.004 <0.01).(4)It was obvious that the expression of HIF-1? increased significantly in non-responder patients of colorectal cancer andHT-29/L-OHP than in responders and HT-29 respectively,Furthermore,HIF-1?expression level in colorectal cancer tissue was positively correlated with ANXA3.The expression of HIF-1? in the group transfected with ANXA3 si RNA appeared to be lower than that in the control groups.Conclusions: ANXA3 affects colorectal cancer drug resistance by HIF-1?.ANXA3 could become a clinical prediction molecular marker for colorectal cancer drug resistance.