LEP and endometrial cancer: In a study where leptin was added to various human endometrial cancer cell lines, e.g., Ishikawa cells, HEC-1A cells (moderately differentiated adenocarcinoma), RL95-2 cells (moderately differentiated adenosquamous carcinoma), and AN3CA cells, leptin stimulation resulted in increased expression of cyclooxygenase (COX)-2 mRNA and prostaglandin E2 (PGE2) production (Gao et al., 2009).