UNLABELLEDObjective：To explore the effect of tyrosine phosphorylation sites Tyr644 and Tyr664 in oncogenic protein NPM-ALK on cell cycle and its related mechanisms.

METHODSTransiently transfected 293T cells and stably transfected Jurkat cells were used for analysis of cell cycle and protein after the transfection with the constructed recombinant plasmid pEGFP-N1, pEGFP-N1-NPM-ALK and pEGFP-N1-NPM-ALK(644, 664); soft agar assay for colony formation was performed to examine the different carcinogenicity of stable cell lines; cell viability of stable cell lines was examined by CCK-8 after the treatment with PPP.

RESULTSThe S arrest occurred in both NPM-ALK(644,664) transfected 293T and Jurkat cells; the susceptibility of NPM-ALK transfected Jurkat cells to PPP was highest among the 3 stable cell lines; the phosphorylated levels of AKT, ERK and STAT3 were decreased in NPM-ALK(644,664) cells compared with the NPM-ALK ones. Additionally, the double mutation induced the increase of CDK2 and the decrease of P27 (P<0.05).

CONCLUSIONThe mutation of Tyr644 and 664 sites in NPM-ALK can induce cell cycle arrest in S phase and lower susceptibility to PPP that may be related with the phosphorylation change of cell growth related molecules in the downstream of NPM-ALK.

Cell Cycle ; Cell Proliferation ; Cell Survival ; Humans ; Jurkat Cells ; Oncogenes ; Phosphorylation ; Protein-Tyrosine Kinases ; Signal Transduction ; Transfection ; Tyrosine