Molecular characteristics of patients with resectable hepatocellular carcinoma.

Abstract

e16140 Background: Hepatocellular carcinoma (HCC) is one of the most common malignancies and leading cause of cancer deaths worldwide. Biomarkers contribute to predict the response of targeted treatments and immunotherapy. Therapy directed toward homologous recombination deficiency (HRD) is now approved in ovarian and breast cancer, but the pattern of HRD is not clear in HCC. The HRD phenotype has been defined as the presence of a non-silent somatic mutation in homologous recombination-related (HRR) genes. Thus, we aimed to analyze the molecular characteristics of resectable HCC, including HRR genes. Methods: Matched tumor/normal DNA from resectable HCC patients (N = 53) were analyzed by whole exome sequencing (WES) or Acornmed panel with 808 cancer-related genes. Results: Overall, 94.3% (50/53) patients exhibited genetic alterations. TP53, ARID1A, PTEN and NBPF1 were the most commonly mutated genes in resectable HCC. In addtion, 35.9% patinets harbored at least one HRR genes mutation. The frequently mutated genes were BRCA2 (4.4%), BRCA1(4.0%), ATM (3.9 %), and RAD50 (3.8%). Interesting, frequency of HRR genes mutation in the Chinese cohort was higher than that in TCGA (35.9 % vs 20.9%). Analysis of carcinogenic pathways shown that ERBB and PI3K-AKT signaling pathway were the common signaling pathway. In resectable HCC, 32.08% (17/53) patients disclosed high TMB (highest 25%). Further analysis found that PTEN mutations were remarkably associated with low TMB (p < 0.05). Conclusions: This study contributes to understand the molecular characteristics of patients with resectable HCC, which will be useful to guide personalized therapy and promote the clinical management in this population. Furthermore, the study suggested that it is feasibility for resectable HCC patients received PARP inhibitors, DNA-damaging chemotherapies, and immune checkpoint blockade therapy.