AIM:To investigate the effect of liraglutide ( LG) on the expression of fibronectin type Ⅲdomain-containing protein 5 (FNDC5) in the C2C12 myotubes.METHODS:The C2C12 mouse myoblast cell line was induced to differentiation.Differentiated cells were stimulated with gradient concentrations (1 ~1000 nmol/L) of LG for different time (0 ~24 h).The effects of LG on the expression of FNDC5 and the activation of adenosine 5'-monophosphate ( AMP)-activated protein kinase ( AMPK) signaling pathway were determined .After pretreated with glucagon-like peptide-1 ( GLP-1 ) receptor antagonist exendin 9-39 , the inhibitor of Ca 2+/calmodulin-dependent protein kinase kinase 2 (CAMKK2), STO609, or the inhibitor of AMPK, Compound C, the LG-induced FNDC5 expression in C2C12 myotubes was examined.The expression of FNDC5 and the activation of AMPK were determined by Western blot .RESULTS: In C2C12 myotubes, LG promoted the expression of FNDC5 in a dose-and time-dependent manner .LG also activated AMPK signaling pathway .These effects of LG were partly abolished by exendin 9-39 , STO609 and Compound C .CONCLUSION:LG promotes the expression of FNDC5 via GLP-1 receptor in the C2C12 myotubes possibly through activation of the CAMKK2/AMPK signaling pathways .

Malignant pleural mesothelioma(MPM)is a rare,highly aggressive,and lethal tumor with poor prognosis.Its survival period ranges from four months to one year,and the 5-year survival rate is only about 10%.MPM is highly resistant to chemotherapy,and conventional treatments such as cisplatin combined with pemetrexed or raltitrexed only have a certain effect in about 20%of patients.In recent years,with the continuous in-depth understanding of the genetic variation characteristics of MPM,some progress has been made in the molecular mechanism underlying the chemotherapy resistance of MPM.This article will summarize the research progress of the molecular mechanism underlying the chemotherapy resistance of MPM,including BAP1 gene mutation,microRNA,MTA1-mediated DNA damage repair pathway,GITR-GITRL pathway,TGFa pathway,tumor stem cell,EGFR,and PTEN.The aim of this work is to provide a reference for exploring new therapeutic targets and combined treatment options for MPM.