Anti-Proliferative Effects of Piroxicam and Nimesulide on A431 Human Squamous Carcinoma Cell Line

Skin cancer is one of the most common types of cancer worldwide and non-steroidal anti-inflammatory drugs (NSAIDs) have been proposed for prevention and treatment of a variety of cancers. In this study we aimed to evaluate the cytotoxic effects of piroxicam (a non-selective cyclooxygenase (COX) inhibitor) and nimesulide (a highly selective COX-2 inhibitor) on A431 human squamous carcinoma cell line.
Squamous carcinoma cell line (A431) was cultured in RPMI medium containing 10% FBS and penicillin-streptomycin at 37°C and 5% CO2. Cells were treated with different concentrations of piroxicam and nimesulide (100 - 1000 µmol/L) for 24, 48 and 72 hours (h). Anti-proliferative effects were determined using MTT colorimetric assay.
Piroxicam and nimesulide reduced cell viability in a time and concentration dependent manner. The most cytotoxic effect was produced in 72 hours incubation time. The IC50 value of nimesulide was significantly lower than piroxicam in 24 and 72 hours, but not in 48 hours treatment duration.
This study demonstrates that the administration of a highly selective COX-2 inhibitor could probably be more effective than a non-selective NSAID in reducing cancer cells proliferation and that COX-2 can possibly play an important role in skin cancer development.