Areca Nut (Areca catechu Linn.) Extract Induces Cell Cycle arrest and Reduces Ki-67 Activity in Oral Squamous Cell Carcinoma Cells
Oral Squamous Cell Carcinoma (OSCC) is the most common form of oral cancer and the focus on finding chemotherapeutic agents have recently shifted to natural products. Areca nut is a medicinal plant with various biological activities. However, not much data is available on the anti-cancer effect of areca nut extract. Due to the current interest in the potential activity of antioxidant in areca nut extract, we investigated its ability to induce cell cycle arrest and reduce Ki-67 activity in oral cancer cell lines: HSC-2 and HSC-3. The flow cytometry was conducted for the quantification of the cells that underwent cell cycle arrest and had the expression of Ki-67 protein. All determinations were analyzed using the unpaired t-test through SPSS with p<0.01 considered as significant. The areca nut extract induced a significant increase of the cell population in subG1 phase of HSC-2 cells after 24 and 48 hours. The study also found that in HSC-3, there was significant increase in G1 phase after 24 hours treatment, but after 48 hours the areca nut extract couldn’t induce cell cycle arrest. There was significant reduction in Ki-67 expression after 24 hours treatment of areca nut extract in HSC-2 and HSC-3 cells. The increasing of subG1 population showed that apoptosis might be one of the cell death mechanisms by areca nut extract in HSC-2 cells. The cell cycle arrest and the reduction of Ki-67 activities occurred in both cells after 24 hours. These findings suggest that areca nut extract could inhibit the proliferation of OSCC cell lines.