Lymphotoxin-beta receptor activation in bladder cancer cells affecting NF-κB signaling and proliferation

Objective To study the effect of lymphotoxin-beta receptor (LTβR) activation on NF-κB signaling and proliferation of bladder cancer cells. Methods The bladder cancer cells 5637 were cultured in our study,the activation of LTβR was induced by lymphotoxin α1β2(LTα1β2),a functional ligand.The qRT-PCR was applied to detect the mRNA expression of NF-κB family main members (RelA,RelB),cytokines including LTα,LTβ,LIGHT,TNFα,IL-6,IL-1β,and the proliferation-related genes including CyclinD1 and Survivin.The level of phospho-p65(p-p65) was determined by western blot.Cell viability was tested by CCK-8. Results After activation of LTβR,RelA mRNA was up-regulated about 2.5 times (P=0.003),TNFα,IL-1β,CyclinD1 and Survivin mRNA expressions were up-regulated significantly (all P<0.05).Along with the down-regulated expression of LTβR,the mRNA expression of the above-mentioned gene were also decreased (P all<0.05).WB determined that there was an up-regulated trend of p-p65 after activation of LTβR (all P>0.05).There were no significant differences in the proliferation of bladder cancer cells compared to the control (P both>0.05). Conclusion Activation of LTβR can promote the expression of NF-κB family member RelA and the activation of the classical NF-κB signaling.It might be a participant in the emergence of inflammatory microenvironment through up-regulating the expression of TNFα and IL-1β mRNA;Though CyclinD1 and Survivin have been up-regulated,but LTβR has no effect on the proliferation level of bladder cancer cell.