Effect Of Toll-like Receptor Pathway On The Proliferation Of Tumor Cells

Objective To investigate the effect of HSP70 on the proliferation of tumor cells, and analyze the possible mechanism of TLR pathway on tumor cell proliferation. Methods (1) Stimulate H22 cells with LPS and HSP70. The expression level of TLR2 and TLR4 in H22 cells were detected by RT-PCR. (2) Stimulate H22 cells with LPS and HSP70. Western blot was used to detect the expression of GSK3βat different time points. (3) Stimulate H22 cells with LPS and HSP70. The expression ofβ-catenin was evaluated by Western blot. (4) Stimulate MCF-7 cells with HSP70 for 3 days. The expression of cyclinD1a and cyclinD1b was detected by RT-PCR. (5) Stimulate H22 cells with LPS and HSP70 for 2days. Western blot was used to detect the expression of HMGB1. (6) Culture H22 cells and MCF-7 cells with the stimulation of LPS and HSP70, and then to evaluate the cell proliferation by counting the cells. (7) H22 cells were labeled with CFSE and stimulated with LPS, HSP70 and mitomycin. Flow cytometry was used to detect the rate of propagation. (8) H22 cells were stimulated with LPS and HSP70, and injected at right hind thigh of mice to establish the tumor model. Tumor weight and tumor formation time were used to reflect the effects of LPS and HSP70 on tumor growth. Results (1) The expression level of TLR2 and TLR4 in H22 cells was significantly increased after stimulation of LPS and HSP70. (2) After stimulation of LPS and HSP70, the level of phosphorylated GSK3βin H22 cells was increased, while the level of nonphosphorylated GSK3βwas not changed. (3) After stimulation of LPS and HSP70 for 24 hours, the expression level ofβ-catenin in H22 cells was obviously increased. (4) After stimulation of HSP70, the expression level of cyclinD1a was increased. (5) After stimulation of LPS and HSP70 for 2 days, the expression level of HMGB1 increased. (6) After stimulation of LPS and HSP70, the proliferation rate of treatment group was obviously higher compared with control group. (7) After proceeded with mitomycin, H22 cells were stimulated with LPS and HSP70. The proliferation rate of treatment group was obviously higher compared with control group. (8) After stimulation of LPS and HSP70 for 2 days, tumor formation time and tumor weight of treatment group were much higher than control group. Conclusion LPS and HSP70 could activate toll-like receptor signaling pathway and raise the proliferation rate of tumor cells.