J Cancer 2018; 9(11):1989-2002. doi:10.7150/jca.23762 This issue
1. Institute of Materia Medica, College of Pharmacy, Army Medical University (Third Military Medical University), Chongqing 400038, China;
2. Center of Hepatobiliary Pancreatic Disease, Beijing Tsinghua Changgung Hospital, Beijing 102218, China;
3. Brigade 315th of Territorial Defense Force, Chinese People's Liberation Army Ground Force, Xishuangbanna District, Yunan 666200, China;
4. Health Physical Examination Center, The Affiliated Hospital of Qingdao University, Qingdao, Shandong 266003, China.
5. Diagnosis and Treatment Center for Servicemen, Southwest Hospital, Army Medical University (Third Military Medical University), Chongqing 400038, China.
6. Institute of Hepatobiliary Surgery, Southwest Hospital, Third Military Medical University, Chongqing 400042, China.
Integration of public genome-wide gene expression data together with Cox regression analysis is a powerful weapon to identify new prognostic gene signatures for cancer diagnosis and prognosis. Hepatitis B virus (HBV) is a major cause of hepatocellular carcinoma (HCC), however, it remains largely unknown about the specific gene prognostic signature of HBV-associated HCC. Using Robust Rank Aggreg (RRA) method to integrate seven whole genome expression datasets, we identified 82 up-regulated genes and 577 down-regulated genes in HBV-associated HCC patients. Combination of several enrichment analysis, univariate and multivariate Cox proportional hazards regression analysis, we revealed that a three-gene (SPP2, CDC37L1, and ECHDC2) prognostic signature could act as an independent prognostic indicator for HBV-associated HCC in both the discovery cohort and the internal testing cohort. Gene set enrichment analysis showed that the high-risk group with lower expression levels of the three genes was enriched in bladder cancer and cell cycle pathway, whereas the low-risk group with higher expression levels of the three genes was enriched in drug metabolism-cytochrome P450, PPAR signaling pathway, fatty acid and histidine metabolisms. This indicates that patients of HBV-associated HCC with higher expression of these three genes may preserve relatively good hepatic cellular metabolism and function, which may also protect HCC patients from persistent drug toxicity in response to various medication. Our findings suggest a three-gene prognostic model that serves as a specific prognostic signature for HBV-associated HCC.
Keywords: Hepatitis B virus associated hepatocellular carcinoma, Robust Rank Aggreg analysis, Hub genes, Prognostic signature, Overall survival.