PTGER1 and ovarian cancer: Previous studies showed that phosphatase of regenerating liver-3 suppressed ITGA2 expression in ovarian cancer cells at the transcription level [22], and COX-2 increased ITGA2 expression through the EP1/PLC/PKCα/c-Src/NF-κB signal transduction pathway in human chondrosarcoma cells [23], the strikingly decreased methylation at key CpG sites within the promoter of ITGA2 gene in prostate tumors, compared with normal prostate tissue [24].