Full-length Mst1 exhibits growth promoting function in human hepatocellular carcinoma cells.
The putative tumor suppressor Mst1, when cleaved to its 36kDa cleaved form, amplifies apoptotic signals. We found that Mst1 was predominantly expressed in its full-length form in 76% (17/25 cases) of hepatocellular carcinoma (HCC) tumors. Mst1 cleavage was basically absent in HCC cells. Ectopic full-length Mst1 expression increased the growth of HCC cells by 55-80% within 3days after transfection. Expression of exogenous NORE1B, a tumor suppressor commonly lost in HCC tumors (~56% of our cohort), was sufficient to suppress the growth promotion of full-length Mst1. Hence, Mst1 exhibits a growth promoting activity in HCC cells upon NORE1B downregulation.
Department of Pharmacology and Chemical Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA 15232, USA. yun16@pitt.edu
Yuen-Keng
YK
Ng
Wing-Sze
WS
Lau
Vivian Wai Yan
VW
Lui
Alfred Sze-Lok
AS
Cheng
Patrick Kwok-Shing
PK
Ng
Stephen Kwok-Wing
SK
Tsui
Yue Sun
YS
Cheung
Paul Bo San
PB
Lai
D048868:Adaptor Proteins, Signal Transducing; D017209:Apoptosis; D051017:Apoptosis Regulatory Proteins; D006528:Carcinoma, Hepatocellular / Q000378:metabolism* / Q000473:pathology; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D002470:Cell Survival; D004252:DNA Mutational Analysis; D015870:Gene Expression; D015972:Gene Expression Regulation, Neoplastic; D057809:HEK293 Cells; D017228:Hepatocyte Growth Factor / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D006801:Humans; D008113:Liver Neoplasms / Q000378:metabolism* / Q000473:pathology; D008970:Molecular Weight; D020559:Monomeric GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism; D059748:Proteolysis; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D015854:Up-Regulation
D048868:Adaptor Proteins, Signal Transducing; D051017:Apoptosis Regulatory Proteins; D011518:Proto-Oncogene Proteins; C454042:RASSF5 protein, human; C082332:macrophage stimulating protein; D017228:Hepatocyte Growth Factor; D020559:Monomeric GTP-Binding Proteins