OBJECTIVETo investigate the profile of promoter methylation and expression of SHP-1 gene in the progression of chronic myeloid leukemia (CML).

METHODSThe expression level of SHP-1 mRNA and protein in bone marrow or peripheral blood mononuclear cells from CML patients were detected by Western blot and SYBR Green-based qRT-PCR. The methylation status of SHP-1 were assessed by methylation-specific polymerase chain reaction (MSP) assay. K562 cells were infected with the lentiviral plasmids pEX-SHP-1-puro-Lv105 (K562-SHP-1) or pEX-EGFP-puro-Lv105 (K562-EGFP). The levels of proteins and phosphorylated proteins were detected by Western blot. qRT-PCR assay was used to test the level of BCR-ABL mRNA.

RESULTSThe relative levels of SHP-1 mRNA were sharply decreased in advanced stages CML compared to chronic phase (CP)-CML (0.79±0.37 vs 1.18±0.64, P= 0.009). The level of SHP-1 protein was lower in advanced stages CML compared to CP-CML (0.57±0.02 vs 1.02±0.04, P=0.039). The frequency of SHP-1 gene promoter methylation at selected loci in CP-CML was 23.8% (10/42), and the methylated regions were detected in all advanced CML samples (P<0.01). SHP-1 was stably transfected into K562 cells and selected with puromycin. Overexpression of SHP-1 inhibited the proliferation and induced the apoptosis of K562 cells, meanwhile leaded to G0/G1 phase arrest. After transfection, the level of BCR-ABL mRNA was not affected in K562-SHP-1 cells (1.32±0.34) compared to K562-EGFP cells (1.18±0.20, P=0.644), but overexpression of SHP-1 caused a slight decrease in BCR-ABL protein in K562-SHP-1 cells compared to K562 -EGFP cells (0.78±0.15 vs 1.27±0.24, P=0.040). Overexpression of SHP-1 resulted in a remarkable decrease in MYC protein, phosphorylated forms of JAK2, STAT5, Akt and MAPK. However, the un-phosphorylated forms of these molecules were not significantly affected.

CONCLUSIONDecreased expression of SHP-1 caused by aberrant promoter hypermethylation may play a key role in the progression of CML by dysregulation of BCR-ABL, Akt, MAPK, MYC, JAK2 and STAT5 signaling.

Apoptosis ; DNA Methylation ; Disease Progression ; Fusion Proteins, bcr-abl ; Humans ; Janus Kinase 2 ; K562 Cells ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive ; Leukocytes, Mononuclear ; Phosphorylation ; Protein Tyrosine Phosphatase, Non-Receptor Type 6 ; RNA, Messenger

Lung cancer is one of the most common malignancies with the highest incidence rate and mortality rate worldwide, and non-small cell lung cancer (NSCLC) accounts for about 85%. Only 5% NSCLC patients are anaplastic lymphoma kinase (ALK) rearrangement positive NSCLC, but the prognosis of these patients is poor, and treatment is urgent. Ensartinib (X-396), a next-generation ALK tyrosine kinase inhibitor (ALK-TKI), has shown greater potency on inhibiting ALK activity and controlling brain metastases than crizotinib, which is indicated for the treatment of crizotinib-resistant, ALK-positive NSCLC patients. Several phase I to III clinical trials included both healthy volunteers and NSCLC patients have been conducted both in China and abroad. In this review, we briefly summarized the results of these trials, and preliminary efficacy, safety, pharmacology and pharmacokinetics/pharmacodynamics of ensartinib were discussed.

【Objective】 To evaluate the effect of Arntl on T cell development and T cell-mediated anti-viral immunity. 【Methods】 Arntl^F/FCD4cre⁺(KO) in mice was constructed to delete Arntl gene specifically in T cells. We examined the percentage and number of T cell subsets in the thymus and spleen by flow cytometry (FCM). At day 8 after lymphocytic choriomeningitis virus (LCMV) infection, the proportions of T cell subsets, virus-specific CD8⁺ T cells and IFN-γ secreting T cells were analyzed. The viral load in the spleen was measured using qPCR. Naive CD4⁺ T cells (CD4⁺CD25^-CD44^-CD62L⁺) were sorted by flow cytometry to perform T helper cell differentiation in vitro. 【Results】 The percentage and number of T cells in the thymus and spleen of KO mice showed no significant change compared with those in the control group (Arntl^F/FCD4cre^- mice, WT) (P>0.05). Acute LCMV infection did not cause observable changes in effector T cell proportion in the spleen of KO mice compared to that in WT mice (P>0.05), but KO mice showed a higher proportion of IFN-γ secreting T cells (P<0.05) and better virus clearance (P<0.05). In addition, naive CD4⁺ T cells from KO mice were more prone to differentiate into Th1 cells in vitro (P<0.05). 【Conclusion】 Arntl deletion in T cells does not affect T cell development, but enhances their ability to defend against viral infection by promoting Th1 cell differentiation and response.