EFFECT OF PACLITAXEL ON HEAD AND NECK SQUAMOUS CELL CARCINOMA CELL LINE: AN IN VITRO STUDY

Abstract

Head and neck cancer is one of the most common types worldwide. It is highly curable if detected early. The main approach for HNC treatment is surgery and radiation but more recently clinical trials have demonstrated the benefit of combining chemotherapy and radiation in advanced cases. Paclitaxel, a naturally occurring compound which is extracted from the bark of pacific yew trees, was found to have a cytotoxic effect in many human cancer types such as breast and ovarian carcinomas. The present study aimed to investigate the possible apoptotic and cytotoxic effects of paclitaxel on HNSCC cell lines (Hep-2 cell line) and to evaluate the cytological changes that may occur in paclitaxel treated cells in comparison to untreated control cells. At the same time, the study tried to identify the optimum concentration and duration of these effects. The study utilized cytotoxicity assay as a preliminary test to identify the effect of different paclitaxel concentrations (25, 50 and 100 nM) over different durations (24, 48 and 72 hours) on the viability of Hep-2 cells. Flow cytometry assay was to evaluate the cell cycle progression and DNA content in order to ensure occurrence of DNA fragmentation which is often defined as “sub-G1” or “sub-diploid” cell population on DNA content frequency histograms. The present study also depended on cytological evaluation to identify the presence of morphological hallmarks of apoptosis which offer the gold standard for definitive identification of apoptotic cells. In addition to the qualitative assessment of apoptotic cells provided by morophological