Clinical Utility of CTNNB1 (c.121A>G) Mutation in Circulating Tumor DNA in Egyptian Patients with Hepatocellular Carcinoma: A Case-Control Study

Abstract

Abstract Background Hepatocellular carcinoma (HCC) is the most common malignancy of the liver and with 782,000 new cases annually and 600,000 deaths/year globally. In Egypt, HCC causes a significant public health problem with a rising incidence as it is strongly linked to viral hepatitis mainly HCV. CTNNB1 mutations is one of the most common genetic alterations in HCC. Our aim is to investigate the clinical utility of CTNNB1 (rs121913412) single nucleotide variation (SNV) in ctDNA in patients with early and late-stage HCC in comparison to chronic HCV patients and healthy controls. Methods All participants were subjected to history taking, clinical evaluation, laboratory investigations including liver profile, kidney function tests, alfa-fetoprotein. Additionally, complete blood counts and coagulation profile were done. Child and Model for End-Stage Liver Disease (MELD) scores were calculated, BCLC staging was done for each patient and radiological protocol for HCC (spiral triphasic CT or MRI). Genotyping of rs121913412 CTNNB1 (c.121A>G) on extracted DNA from blood samples was done using Real Time PCR System. Results Thirty patients with HCC on top of HCV were recruited including 14 early HCC and 16 with advanced HCC in addition to non-HCC group including 10 HCV-positive patients and 10 healthy controls. All participants have undergone laboratory investigations and radiological protocol for HCC cases. Genotyping of rs121913412 CTNNB1 (c.121A>G) in peripheral blood samples using RT-PCR for all cases was done. The genotype AA was detected in 27out of 30 (30%) of the cases while 3 HCC cases out of 30 (10 %) were positive for the CTNNB1 p.T41A mutation; AG phenotype (heterozygous), no cases showed GG phenotype. In HCV- positive patients’ group and healthy controls none were positive for the CTNNB1 mutation all showed wild AA genotype. No significant differences in the genotype (AA, AG, GG) distribution between HCC and non-HCC groups (χ2=3.619, p = 0.0571). The frequency of AA vs AG + GG genotype was considerably higher in cases when compared to controls however no statistical significance was detected (χ2=3.619, p = 0.0571). Distribution of A vs G allele in cases compared to controls showed statistically significant difference (χ2=4.571, p = 0.0325). Conclusion In this study we were not able to prove the clinical utility of CTNNB1 rs121913412 in Egyptian HCC patients. Further large multi-centric studies are needed to explore the clinical utility of ctDNA in assessment of tumor-specific hotspot somatic mutations in genes including CTNNB1, TERT and TP53 genes that can be identified in the peripheral blood of HCC patients. Comparison studies utilizing both ctDNA and DNA extracted from HCC tissue samples are recommended.