OBJECTIVETo investigate the expression and relationship of p27(kip1) and its nuclear export factor Jab1 during proliferation process of lymphoma cell.

METHODSJurkat and Raji cells were treated with serum starvation and then serum release. The protein and mRNA expression of p27(kip1), Jab1 in the cells were detected by Western blot and RT-PCR respectively. LMB were used for stimulating Jurkat cells during their proliferation process, and then the expression changes of p27(kip1) and Jab1 were detected. An eukaryotic expression plasmid(pcDNA3. 1-myc) containing Jab1 was constructed. Jurkat cell were transfected in vitro with or without pcDNA3. 1-myc-Jab1. Double immunolabelling was used to identify the localization of p27(kip1). Immunoprecipitation was used to detect the combination of p27(kip1) and Jab1.

RESULTSThe growth of Jurkat and Raji cells were blocked by serum starvation. The total protein amount of p27(kip1) increased while that of Jab1 decreased. The reverse changes were happened after serum release, but the mRNA expression of p27(kip1) has no significant change. LMB could inhibit the cell proliferation caused by serum release. The expression of p27(kip1) was up-regulated and Jab1 down-regulated when Jurkat cells were treated with LMB. After pcDNA3. 1-myc-Jab1 infected Jurkat cells for 48 h, the distribution of p27(kip1) was translocated from nucleus into cytoplasma. p27(kip1) and Jab1 could form compound in Jurkat and Raji cells detected by Immunoprecipitation.

CONCLUSIONJab1 may influence the location and expression of p27(kip1) through integrating with p27(kip1), and then participates in regulating the growth of NHL cell through interfering with the function of p27(kip1).