Expression of Syk and suppressive effect of As2O3 to B lymphoma cells

Abstract

Objective: The expression of syk in various B lymphoma cells, and the sensitivity to As2O3 of various B lymphoma cells that has different expression of syk and the relationship between expression of syk and suppressive effect of As2O3 to B lymphoma cells were investigated. Methods: The expression of syk, p21WAF1/CIP1, bcl‐2 mRNA was examined by semiquantitative RT‐PCR technique. Silenced the expression of syk in Raji cells by RNAi and then assessed the effects of As2O3 on the expression of cell‐cycle related gene p21WAF1/CIP1. Results: Raji and Namalwa cells express syk mRNA, but Ramos cells lack expression of syk mRNA. As same, syk protein can be detected in both Raji and Namalwa cells but can not be detected in Ramos cells, syk was positive in endochylema. As2O3 can significantly inhibit proliferation of Raji, Ramos and Namalwa cells, and with a concentration and time dependent manner (p£¼0.01). RNAi effectively silence expression of syk mRNA and protein in Raji cells, but there was no significant difference in expression of p21WAF1/CIP1 mRNA and protein between before and after treatment with different concentration As2O3 (P£¾0.05). Conclusions: Expression of syk mRNA and protein is positive in both Raji and Namalwa cells, which is negative in Ramos cells. The mechanisms of anti‐tumor effect in vitro by As2O3 associate with blocking cell cycle and inducing cellular apoptosis.