The expression of MIF and Cyclin D1 in hepatocellular carcinoma / 中华普通外科杂志

ABSTRACT

Objective To investigate the expression of macrophage migration inhibition factor (MIF) and cell cycle regulating factor Cyclin D1 in hepatocellular carcinoma tissue and the interaction between MIF and Cyclin D1 in hepatocellular carcinoma cell cycle controlling. Methods Using quantitative real-time PCR and Western blotting to detect mRNA and protein expression of MIF and Cyelin DI in HCC tissues and tumor adjacent tissues. Specific small interfering RNA(siRNA) targeting MIF gene was transfccted at doses of 50 nmol/L and 100 nmoL/L into HCC cell lines of PLC and HepG2 with lipofeetamine 2000 methods to knockdown the expression of M1F gene and to investigare the the interaction between M1F and Cyclin D1. Results MIF and Cyclin D1 protein and mRNA were overexpressed in HCC tumor tissues. The relative expression of MIF,Cyclin D1 protein and mRNA were 0.825±0.13,0.843± 0.104 and 7.31±1.85 folds、4.27±1.05 folds, compared with the tumor adjacent tissues (FMIF= 15.5, P<0.01;FCyclin D1=87.5,P <0.01). In MIF siRNA treated PLC and HepG2 cells, MIF mRNA down regulation 71.2%±7.2%, 87.4%±2.9% ,74.3%±8.9% and 88.4%±4.6% respectively (FPLC = 315.5 ,P < 0.01 ; FHepG2= 201.2 P < 0.01). While MIF protein expression were significandy reduced to 0.33±0.03,0.11±0.02, 0.81±0.08 and 0.36±0.02 in a dose-dependent manner (FPLC= 43.9, P <0.01 ;FHepG2 = 133.4 P <0.01). Cyclin D1 mRNA was significantly down-regnlated in MIF siRNA treated PLC and HepG2 cell lines when compared with control group(P <0.01). In 50 nmol/L and 100 nmol/L groups, Cyclin DI mRNA levels were respectively decreased by 68.2%±3% and 78.1%±1.4% in PLC cell, 65.8%±4.7% and 77.3%±2.6% in HepG2 cell (FPLC= 1569, P < 0.01 ; FHepG2= 480.4, P <0.01). Compared with control groups, Cyclin D1 protein levels significantly reduced to 0.28±0.06、0.15±0.03 and 0.44 ±0.04、0.13±0.02 in the PLC and HepG2 after M IF siRNA treatment(FPLC= 35.5, P < 0.01 ; FHepG2 = 114.7, P < 0.01). Conclusions MIF and Cyclin D1 mRNA and protein were overexpressed in HCC tumor tissues and participated in tumor cell cycle regulation. MIF may up-regnlate the expression of Cyclin DI via ERK signalling and precipitate in carcinogenesis of hepatocellular carcinoma.