Vascular invasion is a critical risk factor for hepatocellular carcinoma (HCC) recurrence and poor survival. The molecular drivers of vascular invasion in HCC are largely unknown. Deciphering the molecular landscape of invasive HCC will help identify novel therapeutic targets and noninvasive biomarkers. To this end, we undertook this study to evaluate the genomic, transcriptomic, and proteomic profile of tumors with vascular invasion using the multi-platform cancer genome atlas (TCGA) data (n=373). In the TCGA liver hepatocellular carcinoma (LIHC) cohort, macrovascular invasion was present in 5% (n=17) of tumors and microvascular invasion in 25% (n=94) of tumors. Functional pathway analysis revealed that the MYC oncogene was a common upstream regulator of the mRNA, miRNA and proteomic changes in vascular invasion. We performed comparative proteomic analyses of invasive human HCC and MYC driven murine HCC and identified fibronectin to be proteomic biomarker of invasive HCC (mouse Fn1 p= 1.7 X 10-11 ; human FN1 p=1.5 X 10-4 ) conserved across the two species. Mechanistically, we show that FN1 promotes the migratory and invasive phenotype of HCC cancer cells. We demonstrate tissue overexpression of fibronectin in human HCC using a large independent cohort of human HCC tissue microarray (n=153; p<0.001). Lastly, we showed that plasma fibronectin levels were significantly elevated in patients with HCC (n=35, mean=307.7 µg/ml, SEM=35.9) when compared to cirrhosis (n=10, mean=41.8 µg/ml, SEM=13.3; p<0.0001). CONCLUSION: Our study evaluates the molecular landscape of tumors with vascular invasion, identifying distinct transcriptional, epigenetic and proteomic changes driven by the MYC oncogene. We show that MYC upregulates fibronectin expression which promotes HCC invasiveness. In addition, we identify fibronectin to be a promising non-invasive proteomic biomarker of vascular invasion in HCC.
View details for DOI 10.1002/hep.31614
View details for PubMedID 33140851