The Study On ALDH1as Marker Of Ovarian Cancer Stem Cell

Present studies confirmed that Aldehyde Dehydrogenase1（ALDH1） can be usedas a marker of most tumor stem cells. There’s few studies focusing on whetherALDH1could act as stem cell markers of ovarian cancer and this is controversial. westudy the role of ALDH1in ovarian carcinoma using ovarian cancer cell line SKOV3.In this study SKOV3cells were cultured in serum free-medium （SFM） to derivesuspension tumor spheres enrichment of stem cells. The proliferation, cloning andinvasion ability of the suspension tumor spheres was analyzed by MTT method, platecolony formation test and transwell migration test. The location and expression ofALDH1in human ovarian cancer cells was detected by Fluorescence confocalmicroscopy after the cells were stained with Hoechst33342and Aldefluor dye liquor.The Aldefluor assay followed by flow cytometr analysis were used to assess the cellpopulation with high ALDH1enzymatic activity and CD133positive in humanovarian cancer SKOV3cells; In vitro chemotherapy experiments were used toexplored ALDH1role initially in ovarian cancer; provide evidence for ALDH1asmarkers of ovarian cancer stem cell.The results prove that the majority of ovarian cancer SKOV3cells were deathin serum-free medium, The loose, irregular in shape, less cell number suspensiontumor spheres was formed after3⁴days. And they became regular, closely, and goodactivity after6⁷days. Then these cell could be digested into Single cell by trypsinfor subsequent experiments. There is no difference at self-renewal andself-proliferation between SKOV3cell and suspension tumor spheres cell aftercultured1to2days by MTT test （p>0.05） and suspension tumor spheres cell grownfasted （p<0.05）. The colony formation rate of tumor sphere cell is higher than that ofSKOV3cell （35.23±5.89%vs20.32±6.42%, p<0.05）. Transwell invasionexperiment show that the number of suspension tumor spheres cell across themembrane was237±37.42and the number of SKOV3cells was87.8±22.13. Thedifference was statistically significant （p<0.05）. ALDH1is expressed in SKOV3cellcytoplasm. When the activity of ALDH1is higher, the product of ALDH1is more in cells and fluorescence intensity is higher. The outline of SKOV3cells is clear,thefluorescence intensity is contrasting between cytoplasmic and nuclear by Hoechst33342and Aldefluor pair staining.The nuclei of SKOV3cell stained by Hoechst33342displayed blue fluorescence, while the nuclei of ALDH1^highcells were notstained. The percentage of ALDH1^high and CD133⁺was4.08±0.29%,1.21±0.34%respectively; ALDH1^high cells, CD133+cells were enriched in serum free-medium,the percentage of ALDH1^high,CD133⁺in tumor sphere was22.42±2.42%,10.34±0.17%, which are significantly higher than those at SKOV3（p<0.05）. Flow cytometryanalyzed showed that the percentage of ALDH1^high cell and CD133⁺cell increased3.23and2.34fold after treated with cisplatin for72hours In vitro Chemotherapy,experiments,The percentage of ALDH1^high and CD133⁺was17.25±3.26%and4.04±0.86%respectively The ALDH1^high cells and CD133⁺cells showed strongerability to survive than the ALDH1low cells and CD133—cells.Conclusion:1． Low proportion ALDH1^high cells and CD133⁺cells in ovarian cancer,were4.08±0.29%and1.21±0.34%respectively.2． ALDH1^highcells and CD133⁺cells were enriched in suspension sphere andafter cisplatin treated3． The ratio of ALDH1^highcell is2times than that CD133⁺cells in suspensiontumor spheres.4． ALDH1can act as a marker of ovarian cancer stem cell.