ANXA2 and cancer: Here we show i) high annexin A2 expression in 90% of serous ovarian cells and increased annexin A2 levels in the cancer-associated stroma, ii) suppression of annexin A2 expression significantly reduces migration and invasion of 4 ovarian cancer cell lines, iii) down regulation of annexin A2 reduces adhesion of ovarian cancer cells to the peritoneal cells, and iv) annexin A2 neutralizing antibodies blocks migration and invasion of ovarian cancer cells, both in vitro and in vivo.