Modulation of E-cadherin and Histone Deacetylase via miR-34c in Epidermoid Carcinoma and Tongue Cancer

Objectives: Oral squamous cell carcinoma (OSCC) is a type of cancer that starts in the squamous cells that line the mouth. It is the most common type of head and neck cancer and accounts for about 90% of all head and neck cancers. MiR-34c is reported as a member of the p53 pathway that may function to disrupt the cell cycle as a result of DNA damage. Thus, understanding the role of this microRNA in the progression of OSCC becomes mandatory. Materia and Methods The present study investigated the expression profile of miR-34c in patients with well-differentiated OSCC compared to tongue squamous cell carcinoma (SCC25) and human epidermoid carcinoma (A253) cells. A total of 25 cases of tissue samples (10 normal oral mucosal tissue and 15 well-differentiated OSCC) were studied for miR-34c expression by qPCR. SCC25 and A253 cells were transfected with miR34c-5p expressing plasmid. Post transfection, cells were tested for DNA content, apoptosis, and E-cadherin expression. Results: The expression profile of miR-34c was significantly lower in patients with well-differentiated OSCC compared to normal oral mucosal tissues ( P = 0.000). Transfection of SCC25 cells and A253 cells with miR-34c induced cell cycle arrest, and resulted in a significant elevation in apoptosis ( P = 0.000). Additionally, the expression of E-cadherin was enhanced in OSCC compared to the control, with a significant decrease in the expression of all tested HDACs. Transfection of miR-34c-5p enhanced by ultrasound significantly forced cell cycle arrest and increased the apoptosis levels, indicating the role of miR-34c-5p in controlling the malignant behavior of OSCC. Conclusion: miR-34c could be an important tumor suppressor in oral malignancy, and miRNA34c mimics might be a reliable approach to combat OSCC. Clinical relevance: Understanding the molecular functions of different types of miRNAs gives a deeper insight into understanding, and hence combating cancers such as OSCC. This might help minimize the invasive interventional treatments.