Alteration of oncogenic IGF-II gene methylation status associates with hepatocyte malignant transformation

Background: Oncogenic insulin-like growth factor-II(IGF-II) is overexpressed in hepatocellular carcinoma(HCC). The present study aimed to analyze the dynamic alteration of IGF-II CpG site methylation status and its molecular mechanism in HCC progression. Methods: IGF-II alterations were observed in rat hepatocarcinogenesis models induced by 2-acetylaminofluorene. Liver IGF-II expression was compared by immunohistochemistry or tissue IGF-II specific concentration(nmol/mg protein). Status of human IGF-II promoter 3(P3) or rat IGF-II P2 CpG site methylation was amplified by methylation-specific polymerase chain reaction(MSP). Serum IGF-II levels were quantitatively detected by an enzyme-linked immunosorbent assay. Results: The levels of hepatic IGF-II expression were significantly elevated in the HCC group( P < 0.001). The unmethylation rate of IGF-II P3 CpG sites was 100% in the HCC-, 52.5% in the paracancerous-, and none(0%) in the distal noncancerous-tissues. Abnormal IGF-II expression was related to differentiation degree, tumor invasion, and positive HBV-DNA(all P < 0.001), with a negative correlation between P3 methylation degree and IGF-II expression. There was a positive correlation between liver IGF-II specific concentration and circulating IGF-II level( r = 0.97, P < 0.001). Significantly negative correlation was found between IGF-II P2 CpG site methylation and circulating IGF-II( r s =-0.89, P < 0.001) or liver IGF-II level( r s =-0.84, P < 0.001). Conclusions: The increase of serum IGF-II and the alteration of oncogenic gene IGF-II methylation may be biomarkers for HCC diagnosis and DNA methylation may be the therapeutic target of HCC.

Dynamic expression of hepatic GP73 mRNA and protein and circulating GP73 during hepatocytes malignant transformation

Background:Hepatic Golgi protein-73(GP73)expression is related to hepatocellular carcinoma(HCC)progression.The aim of this study was to investigate the dynamic expression of GP73 mRNA and protein during hepatocytes malignant transformation.Methods:Human GP73 expressions in 88 HCC tissues and their self-control surrounding tissues were examined by immunohistochemistry,and survival time of HCC patients was evaluated by the Kaplan-Meier method.HCC model of Sprague-Dawley rats was made by diet containing 2-fluorenylacetamide.The rats were divided into the control,hepatocyte degeneration,precanceration,and HCC groups to observe GP73 protein and mRNA alterations during hepatocytes malignant transformation.Results:The GP73 expression was significantly higher in the cancerous tissues than that in the surrounding tissues,with shorter survival time,and the positive rates of GP73 protein in human HCC tissues were 53.3%at stage I,84.0%at stage II,84.6%at stage III,and 60.0%at stage IV,respectively.The positive rates of hepatic GP73 protein and mRNA in the rat models were none in the control group,66.7%and 44.4%in the hepatocytes degeneration group,88.9%and 77.8%in the hepatocytes precanceration group,and 100%in the HCC group,respectively.There was a positive correlation(r=0.91,P<0.01)between hepatic GP73 and serum GP73 during rat hepatocytes malignant transformation.Conclusions:Abnormal GP73 expression may be a sensitive and valuable biomarker in hepatocarcinogensis.

Oncogenic tuftelin 1 as a potential molecular-targeted for inhibiting hepatocellular carcinoma growth

BACKGROUND Abnormal tuftelin 1(TUFT1)has been reported in multiple cancers and exhibits oncogenic roles in tumor progression.However,limited data are available on the relationship between TUFT1 and hepatocellular carcinoma(HCC),and the exact biological mechanism of TUFT1 is still poorly understood in HCC.AIM To investigate TUFT1 expression in HCC and how interfering TUFT1 transcription affects HCC growth.METHODS TUFT1 in HCC and non-HCC tissues based on databases of the Cancer Genome Atlas and Oncomine were analyzed,and TUFT1 in human HCC tissues on microarray were detected by immunohistochemistry for clinicopathological features,overall survival,and disease-free survival.HCC cells were transfected with constructed vectors of TUFT1 that interfere or over-express TUFT1 for analyzing the biological behaviors of HCC cells.Proliferation,invasion,migration,and apoptosis of cells were detected by cell counting kit-8,scratch assay,transwell tests,and flow cytometry and confirmed by Western blotting,respectively.RESULTS Abnormal TUFT1 levels in databases expressed in HCC at messenger RNA(mRNA)level and HCC tissues were mainly located in cytoplasm and membrane.The level of TUFT1 expression in the HCC group was significantly higher(χ2=18.563,P<0.001)than that in the non-cancerous group,closely related to clinical staging,size,vascular invasion of tumor,hepatitis B e-antigen positive,and ascites(P<0.01)of HCC patients,and negatively to HCC patients’overall survival and disease-free survival(P<0.001).After interfering with TUFT1 transcription at mRNA level in the MHCC-97H cells by the specific TUFT1-short hairpin RNA,cell proliferation,invasion,and metastasis were significantly inhibited with increasing apoptosis rate.In contrast,proliferation,invasion,and migration were significantly enhanced after over-expression of TUFT1 mRNA in Hep3B cells in vitro.CONCLUSION Oncogenic TUFT1 was associated with the progression of HCC and could be a potential molecular-target for inhibiting HCC growth.