Effects Of Two Soy Isoflavones On Cacer Cell (Ec109) And Normal Cell (HEEC) In Ridiation Therapy

Objective：Here, to investigate the chemical modification effects ofradiation by isoflavone, GENistein (GEN) and DAIdzein (DAI), the mostabundent components in Soy isoflavone, were elvaluted on esophagealcarcinoma (EC109) and normal esophageal epithelial（HECC）cells cobinedwith irradiation treatment.Methods：The EC109and HEEC cells in logarithmic phase were treatedwith different concentrations of GEN or DAI before irradiation，then thesetreated cell were compared with untreated group and irradiation group.The CCK8was used to detect the survival rates of EC109cells and HEECcells, and the clone formation assay was used to test clone formation rates ofdifferent experimental group cells after irradiation.24h,48h and72h afterirradiation,the cells were collected and stained by Annexin-V/PI, theapoptosis rates of these cells were caculated by FACS within an hour. Finally,the pretreatments of the cells were as the same before, then the expressionlevel of Bcl-2and XRCC1GENes of different groups of the two cell lineswere monitered by qPCRResults：The CCK8detection showed that after6Gy X ray radiation, thesurvival rates of EC109cells pretreated with different concentrations of5umol/L、10umol/L、15umol/L、20umol/L、25umol/L,30umol/L of GEN weresignificantly lower than those only irradiation group(P<0.05),which indicatedthat GEN played a cooperative role on the apoptosis rates after irridiation andhad a radiosensitizing effect on EC109cells. At the same concentrations of GEN, the survival rates of HEEC cells were respectively36.71%、43.64%、50.91%、65.37%、71.73%, which were obviously higher than the radiationgroup(P<0.05). The results showed that GEN prevented HEEC cells fromradiation in a dose-dependent way. Simmilarly, DAI decresed the survival rateof EC109cell but the differences of survival rates among groups wereinsignificant(P>0.05). The survival rates of HEEC cells pretreated with5umol/L、10umol/L、15umol/L、20umol/L、25umol/L,30umol/L of DAI weresignificantly higher than those radiation cells(P<0.05), which indicated thatDAI can proctect HEEC cells from being injured by radiation. The results ofclone formation assay showed that changes of clone formation rates betweenEC109and HEEC pretreated by GEN before radiation were obviouslydifferent. The clone formation rates of EC109were lower than theirridiational cells, while which of the HEEC were higher than the irridiationalcells(P<0.05). The variation tendency of clone formation rates of EC109andHEEC pretreated by DAI befroe radiation was similar to that of pretreatedwith GEN(P<0.05). The results of FACS showed that the apoptosis rates ofEC109cells of radiation groups were respectively24.08%、28.64%and35.77%,24h,48h and72h after radiation respectively,. And the apoptosisrates of group pretreated with GEN were respectively37.77%、38.56%、56.16%, and the apaptosis rate pretreated with DAI b were36.38%、43.52%、52.71%(P<0.05),24h,48h and72h after radiation respectively,At the sametime, the HEEC cells of apoptosis rates of radiation group were42%、44.56%,which of pretreated with GEN before irradiation group were respectively33.87%、23.79%, and the HEEC cells of apoptosis rates of pretreated withDAI before irradiation group were27.64%、15.49%(P<0.05). The results of qPCR showed that the expressions of XRCC1of EC109cells were obviouslyhigher than that of radiation group, pretreated with GEN group and pretreatedwith DAI before irradiation group, while which of the latter two groups weresignificantly lower than that of the former one.. The changes of Bcl-2weresimiliar as the XRCC1(P<0.05). Whereas, the expressions of XRCC1andBcl-2of HEEC cells treatmented with GEN and DAI were significant lowerthan the irradiation groups(P<0.05).Conclusion：Both of GEN and DAI can enhanved the apoptosises ofEC109induced by X ray, which have dose-effect relations at a certain extent.While, GEN and DAI displayed a protection role on HEEC cell when irradiedby X-ray. In a word, both of GEN and DAI have the function of increasing thesensibility of radiation on EC109, meanwhile, reducing the injuries of HEECcaused by radiation. The protection effect were more significant when thosecells were treated by a higher concentration(30umol/L) radiation, especiallyby DAI., Moreover, GEN and DAI can alter the expression of XRCC1andBcl-2on EC109and HEEC cells, which might contribute to their effects oncells..