巴西苏木素通过调节c-Fos/TNFAIP3轴抑制膀胱癌的作用机制研究OA

Objective Brazilin is the main active component of the Chinese medicine Caesalpinia sappan wood.To investigate the effect of brazilin on bladder cancer and the possible mechanism involved through in vitro and in vivo studies.Methods Brazilin inhibition of proliferation of T24 cells and T24 overexpressing Fos proto-oncogene(T24-c-Fos)cells was detected using methyl thiazolyl tetrazolium assay,and its effects on migration and colony formation were detected using cell scratch and colony formation assays.Its effects on c-Fos,tumor necrosis factor alpha-induced protein 3(TNFAIP3),and nuclear factor(NF)-κB in both cell types were detected with reverse-transcription quantitative PCR(RT-qPCR)and Western blot at the mRNA and protein levels,respectively.Murine T24 and T24-c-Fos cell orthotopic transplanted bladder tumor models were constructed and exposed to brazilin,and bladder weights were dissected and recorded after 60 days.HE staining was used to observe bladder tumor morphology,and tumoral c-Fos,TNFAIP3,and NF-κB expression was detected by immunohistochemistry,RT-qPCR,and Western blot.Results Brazilin inhibited T24 and T24-c-Fos cell proliferation,migration,and colony formation(P＜0.05);the inhibitory effect on T24-c-Fos cells was significantly increased(P＜0.05)compared with T24 cells.Brazilin significantly upregulated c-Fos and TNFAIP3 expression in T24 and T24-c-Fos cells at both the mRNA and protein levels compared with the corresponding blank control group,and significantly downregulated NF-κB expression(P＜0.05);their degree of change was more significant in T24-c-Fos cells compared with T24 cells(P＜0.05).Murine orthotopic transplanted bladder tumor models were successfully constructed with both cell types;bladder weights after brazilin treatment were lower than those in the corresponding model groups(P＜0.05).The inhibitory effect of brazilin on orthotopic transplanted bladder tumors bearing T24-c-Fos cells was significantly higher than in those bearing T24 cells(P＜0.05).HE staining showed that bladder structure disappeared in all experimental groups,with densely packed tumor cells exhibiting nuclear atypia and a high nuclear-to-cytoplasmic ratio;a large number of necrotic cells were observed in the T24+brazilin and T24-c-Fos+brazilin groups,showing nuclear pyknosis or karyolysis.Immunohistochemistry,RT-qPCR,and Western blot showed that brazilin promoted c-Fos and TNFAIP3 expression and decreased NF-κB expression in orthotopic transplant bladder tumors;these changes were more significant in tumors bearing T24-c-Fos cells compared with those bearing T24 cells(P＜0.05).Conclusions Brazilin may upregulate TNFAIP3 expression through c-Fos,inhibiting NF-κB signaling and exerting anti-bladder cancer effects.