Abstract
Over 90% of primary liver tumors are hepatocellular carcinomas (HCCs). In mammalian cells, chromatin remodeling and transcription regulation are significantly influenced by DNA methylation. Many cancers demonstrate both generalized DNA hypomethylation and localized DNA hypermethylation. Epithelial Cadherin (E-cadherin), a critical molecule in cell adhesion and cancer progression, is involved in these processes. This study aimed to investigate the biological role of DNA methyltransferase 1 (DNMT1) in HCC and its association with E-cadherin gene expression in HCC development. The study included 120 HCC patients from Egypt and 25 healthy individuals. Peripheral blood samples were collected from both groups, and quantitative real-time PCR was utilized to measure the expression levels of the E-cadherin and DNMT1 genes. All participants underwent a comprehensive medical history review and clinical examination. Additionally, the patients had laboratory tests, including serum alanine aminotransferase (ALT), serum aspartate aminotransferase (AST), α-fetoprotein (AFP), albumin, serum creatinine, total leukocyte count (TLC), and platelet count. The results revealed significantly higher levels of these biochemical markers in the HCC group compared to the control group (P values < 0.005). Notably, DNMT1 expression was significantly higher in HCC samples compared to those from healthy controls. In contrast, the expression of E-cadherin was significantly reduced in the HCC group. Furthermore, our findings revealed that the relative gene expression of DNMT1 was negatively correlated with the relative gene expression of E-cadherin, AFP, and tumor size, while E-cadherin expression was negatively correlated with AFP and tumor size. These results suggest that DNMT1 may play a vital role in regulating E-cadherin expression, which could influence the migratory behavior of HCC cells.