Research On Curcumin As A Potential IL-6 Inhibitor In Anti-human Prostate Cancer Cells

[Objective]To investigate the effects of curcumin on the proliferation,apoptosis and autophagy of human prostate cancer cells(DU145,LNCAP)and its effect on the expression of IL-6/JAK2/STAT3 pathway.[Methods]1.The effects of curcumin on proliferation inhibition in human prostate cancer cell lines(DU145,PC-3,LNCAP)at different concentrations and time points were examined using SRB assay.2.The effect of different concentrations of curcumin on the clonogenic ability of human prostate cancer cell lines(DU145,LNCAP)was examined using a plate cloning assay.3.Fluorescence microscopy was used to observe the cells at different times of drug action,and the cell survival status was observed microscopically and photographed.4.The effect of different concentrations of curcumin on the proliferation of human prostate cancer cell line(DU145,LNCAP)was detected by EdU staining.5.To detect the effect of curcumin on the expression of factors related to IL-6/JAK2/STAT3 pathway in prostate cancer cells by protein immunoblotting.6.To detect the effect of curcumin on the expression of apoptotic proteins associated with prostate cancer cells by protein immunoblotting.7.To detect the effect of curcumin on the expression of autophagy factors associated with prostate cancer cells by protein immunoblotting.8.To detect the possible regulation of apoptosis and autophagy of prostate cancer cells by curcumin through IL-6/JAK2/STAT3 pathway by protein immunoblotting.[Results]1.The results of SRB assay showed that curcumin exhibited a significant inhibitory effect on the proliferation of human prostate cancer cell lines,and the effect was drug concentration and time-dependent.2.The results of the plate cloning assay showed that the cell clone formation ability was significantly weakened in the curcumin-treated group compared with the control group,and the proliferation was significantly inhibited with drug concentration dependence.3.Fluorescence microscopy observation of the photographs found that with the prolongation of curcumin action time,the cell morphology began to shrink and become round,local cell fusion was found,the phenomenon of necrotic cell disintegration,the increase of necrotic cells,indicating that the killing ability of the drug on the cells also increased,consistent with the SRB results.4.The cell proliferation was detected by EdU kit after 24h of curcumin action at different concentrations,and compared with the control group,it could be found that the red fluorescence in the field of view was less than that of the control group,and it was proportional to the concentration.5.The results of protein immunoblotting assay showed that the relative expression of p-JAK2 and p-STAT3 in the IL-6/JAK2/STAT3 pathway of both cells treated with curcumin was reduced to different degrees.6.The results of protein immunoblotting assay showed that the protein expression of PARP1 and Cleaved-caspase3 were significantly increased and the protein expression of Bcl-2 were significantly decreased after different concentrations of curcumin treated cells in the selected drug-treated prostate cancer cell lines compared with the control group;the protein expression of PARP1 and Cleaved-caspase3 were significantly decreased after different times of treatment with the same concentration of curcumin in the prostate cancer cell lines.The protein expression of cleaved fragments of PARP1 and Cleaved-caspase3 increased significantly with time,and the protein expression of Bcl-2 decreased significantly with time.The results of protein immunoblotting assay showed that the protein expressions of Beclin-1 and LC3B were significantly increased after different concentrations of curcumin treatment in the selected drug-treated prostate cancer cell lines compared with the control group;the protein expressions of Beclin-1 and LC3B were significantly increased after different times of curcumin treatment in the same concentration in the prostate cancer cell lines.The results of protein immunoblotting showed that the protein expression of PARP1,Cleaved-caspase3,Beclin-1 and LC3B increased significantly under the effect of curcumin,and the protein expression of Bcl-2 decreased significantly,and the expression of IL-6+Cur returned to some extent after the joint action.STAT3 pathway may regulate apoptosis and autophagy in prostate cancer cells.[Conclusion]Curcumin can inhibit the proliferation of prostate cancer cells,induce apoptosis,and is toxic to prostate cancer cells;further study revealed that curcumin can promote apoptosis and autophagy in prostate cancer cells through mediating IL-6/JAK2/STAT3 signaling pathway.