| Objective: To explore the effects of adenosine on hMLH1genemethylation of human colorectal cancer SW480cells.Methods: The SW480cells were treated with adenosine atconcentrations of0,1.5,3.0,4.5mmol/L for72h, the hMLH1genemethylation levels of the CpG islands were detected by Bisulfitesequencing polymerase chain reaction (BSP), hMLH1mRNA expressionlevels were detected by reverse transcription-polymerase chainreaction(RT-PCR), the expression levels of hMLH1protein were detectedby Western blot, and the apoptotic rates were detected by flow cytometry(FCM); the SW480cells were treated with adenosine at concentrations of0,1.5,3.0,4.5mmol/L for24,48,72,96h, the proliferation rates of SW480cells were detected by methyl thiazolyl tetrazolium (MTT).Results:(1)After treatment with adenosine for72h, hMLH1promotermethylation levels of1.5mmol/L,3.0mmol/L,4.5mmol/L groups were(65.0±3.5)%,(45.0±11.2)%and (16.0±4.2)%respectively, and were allsignificantly lower than the control group (80.0±3.5)%(P<0.01),(2)themRNA expression levels as0.079±0.010before the treatment with adenosine. After treatment with adenosine, the mRNA expression levelsrespectively as0.230±0.032,0.359±0.029and0.570±0.019, whichincreased dramatically(P<0.01),(3) After treatment with adenosine for72h,the hMLH1protein expression levels of1.5mmol/L,3.0mmol/L,4.5mmol/L groups were0.353±0.016,0.654±0.018and0.854±0.014respectively, and were all significantly higher than the control group0.126±0.016(P<0.01),(4)after treatment with adenosine, the apoptotic ratesof1.5mmol/L,3.0mmol/L,4.5mmol/L groups were (11.9±0.6)%,(20.0±1.8)%and (35.8±1.8)%respectively, and were all significantlyhigher than the control group (3.9±1.4)%, P<0.01),(5)MTT showed that theproliferation rates of all SW480cells were lower than the control group anda time-dosage dependence existed (P<0.05).Conclusion: Adenosine can reverse the abnormal methylation ofhMLH1CpG island, and promote the expression of hMLH1, then restrainthe proliferation and promote the apoptosis of colorectal cancer cells. |
