Patients with pelvic serous cancer have more side population (SP) cells and aldehyde dehydrogenase positive (ALDH+) cells in ascites than in primary foci

Objective To investigate the relationship between pelvic serous cancer stemlike cells(CSC)and peritoneal metastasis. Methods Primary pelvic serous cancer tissues and ascites were obtained from 17 female patients without preoperative chemotherapy from July 2011 to July 2013.Side population(SP)cells and aldehyde dehydrogenase positive(ALDH+)cells were tested by Hoechst33342 staining and ALDH staining respectively to observe their expression difference and their relationship with pelvic metastasis. Results Among the detectable specimen,73.3%(11/15)were detected SP cells positive(percentage of SP cells0.15%),and 100%(10/10)ALDH+cells in either primary foci or ascites.Comparing the cells percentage from different sites in the same patients,73.3%(11/15)of the patients showed higher SP cells in ascites than those in primary tumors(P=0.01),whereas 90%(9/10)of the patiens showed higher ALDH+cells in ascites than those in primary tumors(P=003).Furthermore,patients with both SP positive and more ALDH+cells in ascites showed more metastatic sites than those with only SP positive or ALDH+cells(P0.05),however,they had little difference in metaststic rate(P0.05). Conclusions Higher percentage of SP cells and ALDH+cells in ascites indicates that pelvic serous CSC are related with peritoneal metastasis and disease progression.