Research Progress on the Role of Laminin Subunit Alpha 4 in Diseases / 中国医学科学院学报

Laminin subunit alpha 4 (LAMA4),a member of the laminin family,is present in the intercellular matrix of adult tissues as a major component of basement membrane.LAMA4 is involved in the adhesion of cells and can bind to corresponding integrins to activate relevant signaling pathways,playing an essential role in the growth,proliferation,and migration of cells.It has been demonstrated that LAMA4 is associated with the occurrence and development of a variety of diseases including tumors,and the expression of LAMA4 can be used as a biomarker of tumor diagnosis and prognosis.This paper summarizes the current research progress in LAMA4 with the focus on the relationship between LAMA4 and diseases,especially tumor,with a view to provide new directions for the future research.

AQP9 protein phosphorylation decreases arsenic influx in mammal cells / 中国药学杂志

OBJECTIVE: To detect the levels of aquaglyceroporin 9 (AQP9) mRNA expression, AQP9 and p38 proteins and their phosphorylation in HepG2 and L-02 cells treated with NaAsO2, and to investigate the association of these expression levels with arsenic intake and the AQP9 phosphorylation mechanism. METHODS: The intracellular arsenic content was determined by inductively coupled plasma mass spectrometry (ICP-MS). Real-time quantitative PCR, Western blotting and immunoprecipitation techniques were used to detect AQP9 mRNA, AQP9 and p38 protein levels and their phosphorylation levels in HepG2 and L-02 cells. SPSS statistical software was used to analyze experimental data. RESULTS: Intracellular arsenic content and intake rate in HepG2 cells were faster than those in L-02 cells. AQP9 mRNA levels in L-02 cells was increased with time within 6 h after NaAsO2 treatment (P<0.05), while no significant change was observed in L-02 cells. Two hours after treatment, AQP9 gene levels in HepG2 cells were all significantly increased at different concentrations of NaAs02. The phosphorylation levels of AQP9 in HepG2 cells were increased with treating time and concentration of NaAsO2. While the phosphorylation levels of AQP9 in L-02 cells significantly increased compared to control at each time point and concentration, but no significant difference was shown between the treatments. p38 phosphorylation levels in both cells were increased with time. Inhibition of p38 activity by SB203580 completely abolished AQP9 protein phosphorylation in L-02 cells, while it had no significant effect on HepG2 cells. CONCLUSION: AQP9 expression and phosphorylation levels may play an important role in regulating arsenic influx; regulation mechanism of AQP9 phosphorylation may be different in different cells. Copyright 2012 by the Chinese Pharmaceutical Association.