Whole-exome sequencing identifies mutated PCK2 and HUWE1 associated with carcinoma cell proliferation in a hepatocellular carcinoma patient.

Hepatocellular carcinoma (HCC) is diagnosed in more than half a million individuals worldwide every year. It is often invasive and metastatic, resulting in a poor prognosis. Our knowledge of the genomic alterations implicated in HCC initiation and progression is fragmentary, and few molecular alterations unique to HCC are known. We performed whole-exome sequencing for a pleomorphic cell-type HCC tissue and matched normal tissue, and uncovered seven non-synonymous somatic variants in SPATA21, PPCS, CDH12, OR1L3, PCK2, HUWE1 and PHF16. These variants were validated by PCR and sequencing, with the exception of that in PPCS. We further performed a bioinformatics analysis of the six validated variants. The results suggested that the function of the proteins of the three mutated genes, PCK2, HUWE1 and PHF16, may be changed significantly. Among these genes, PCK2, within the insulin signaling pathway, and HUWE1, within the ubiquitin-mediated proteolysis pathway, may be essential for cell proliferation. These pathways are known to be important for hepatocarcinogenesis. Hence, we suggest that PCK2 and HUWE1 are associated with carcinoma cell proliferation in HCC.