The Effect Of HIF-1α Regulating β-catenin On Radiosensitivity Of Pulmonary Adenocarcinoma Cells

Objective: To construct a model of radiation resistance of lung adenocarcinoma cells;the expression of HIF-1α in the sh RNA target silencing resistance strains mediated by lentivirus,the effect of HIF-1α on the modulation of β-catenin and radiosensitivity of pulmonary adenocarcinoma cells were investigated.Methods: The H1299 and A549 of human lung adenocarcinoma were induced by the sub-lethal dose method to resist H1299 R and A549 R.The radioresistance of resistant cell was verified by colony formation assay,the change of proliferative ability was measured by the CCK-8 experiment,the expression of genes and proteins in HIF-1α,β-catenin,Cyclin D1,Survivin were detected by q RT-PCR and Western Blot techniques.The target silent HIF-1α of sh RNA,lentivirus expression vector and lentivirus transfection H1299 R,A549R cells were constructed by RNAi technique.The change of radioresistance was verified by colony formation assay.The changes of protein expression of HIF-1α,β-catenin,Cyclin D1,Survivin were verified by Western Blot technique.Results: The results of colony formation assay showed that resistant cells had higher clone formation rate than the parental cells(P<0.05),SF2 of H1299 R cell is 1.56 times of H1299 cell,SF2 of A549 R cell is 1.55 times of A549 cell,resistance of radiotherapy was enhanced in resistant cells.CCK-8 results showed that the cell increment ability of parental cell after 4Gy ray intervention was inhibited significantly(P<0.05);q RT-PCR and Western Blot results showed that the expression of genes and proteins of HIF-1α,β-catenin,Cyclin D1,Survivin in resistant cell were significantly higher than parental cell(P < 0.05);After the lentivirus mediated sh RNA downregulated the level of HIF-1α in resistant cell,the protein expression of β-catenin,Cyclin D1,Survivin was decreased markedly in the lower group(P < 0.05);the protein expression of β-catenin,Cyclin D1,Survivin was significantly lower than control group after the increase of irradiation dose(P < 0.05);The results of colony formation assay showed that the clone formation rate of the down-regulated group was significantly decreased than the control group(P < 0.05).The SF2 of H1299 R in control group is 3.56 times of the down-regulated by radiation sensitivity parameters analysis.The SF2 of A549 R was 2.45 times of the down-regulated group,the radiosensitivity was increased markedly in down-regulated group.CCK-8 results showed that the cell proliferative capacity was decreased significantly in down-regulated group than control group(P<0.05).The cell proliferative capacity was reduced significantly after6 Gy irradiation intervention in down-regulated group(P<0.05).Conclusion: HIF-1α regulating β-catenin which affects the radiosensitivity of pulmonary adenocarcinoma cells,and its mechanism may be related to the expression of Cyclin D1,Survivin and other proteins.