PTGS2 and neoplasm: Studies such as those conducted by Ibrahim Metin Ciriset al., Debashri Janaet al., Ari Ristimakiet al., Pereiraet al. and Costaet al. have stated that COX- 2 overexpression has the potential to be a useful biomarker for estimating tumor aggressiveness, and that COX-2 expression is associated with aggressive tumor biology, and can behave as a predictor of tumors with bad prognosis.