原人参三醇减轻MDA-MB-231细胞紫杉醇耐药性的机制研究OA北大核心CSTPCD

AIM:To investigate the effect of protopanaxatriol(PPT)on the drug resistance of paclitaxel(PTX)-resistant human breast cancer MDA-MB-231 cells(MB231-PR cells).METHODS:The MB231-PR cells were constructed as cell models.They were treated with PPT,and incubated for a certain period of time according to the experi-mental settings.CellTiter-Glo was used to determine the viability of MB231-PR cells and MDA-MB-231 parental cells(MB231-PT cells).The change of sub-G1 phase was detected by flow cytometry.Western blot was used to evaluate the apoptosis-related proteins,such as cleaved caspase-3,cleaved poly(ADP-ribose)polymerase(PARP),B-cell lymphoma-2(Bcl-2),Bcl-2-associated X protein(Bax)and survivin.The activity of nuclear factor-κB(NF-κB)was detected by lu-ciferase reporter assay and immunofluorescence assay.The mRNA expression levels of interleukin-6(IL-6),IL-8,chemo-kine CXC motif ligand 1(CXCL1),chemokine CC motif ligand 2(CCL2),CD44,NANOG,octamer-binding transcrip-tion factor 4(OCT4),sex-determining region Y-box 2(SOX2)and aldehyde dehydrogenase 1(ALDH1)were detected by qPCR.The protein levels of IL-6 and IL-8 were measured by ELISA.Tumor sphere formation assay was used to evaluate the characteristics of stem cells.RESULTS:(1)The viability of MB231-PR cells was suppressed by PPT treatment in a dose-dependent manner compared with MB231-PT cells(P<0.01).Besides,the viability of MB231-PR cells was de-creased after combined treatment with PPT and PTX(P<0.01),the accumulation of sub-G1 phase was induced(P<0.01),the ratio of Bax/Bcl-2 was elevated(P<0.01),and the protein levels of survivin,cleaved PARP and cleaved cas-pase-3 were increased(P<0.05).(2)After PPT treatment combined with PTX,the mRNA expression of inflammatory cy-tokines(IL-6,IL-8,CXCL1 and CCL2)and cancer stem cell-related markers(OCT4,SOX2,NANOG,ALDH1 and CD44)was reduced(P<0.05),and the protein levels of IL-6 and IL-8 were decreased(P<0.01).The activity of NF-κB in MB231-PR cells was suppressed(P<0.05),and the growth of tumor spheres from MB231-PR cells was damaged(P<0.05).(3)Immunofluorescence assay showed that PTX induced nuclear p-p65 expression,but this effect was attenuated by PPT.CONCLUSION:Combined treatment with PPT and PTX could attenuate PTX resistance of MB231-PR cells by inhibiting inflammatory cytokines and cancer stem cells.