Comparison of extraction methods of exosomes from patients with ovarian cancer

    LI Qiª²Ling1, SUN Yangª²Zhen2, YU Yueª²Cheng3, FANG Jing1, ZHANG Yuanª²Li1, XIN Xiaoª²Yan3

    1Department of Gynecology and Obstetrics, First Affiliated Hospital, Medical College, Xi¬ðan Jiaotong University, Xi¬ðan 710061, China, 2Department of Gynecology and Obstetrics, Xi¬ðan Huanghe Hospital, Xi¬ðan 710043, China, 3Department of Gynecology and Obstetrics, Xijing Hospital, Fourth Military Medical University, Xi¬ðan 710033, China

    ¡¾Abstract¡¿ AIM: To compare the extraction methods of exosomes from tissue or ascites of an advanced ovarian cancer patient, to detect the expression of exosomes of two source, and to explore the best pathway of acquiring exosomes. METHODS: The tissue of ovarian cancer was taken and the cancer cells were separated and cultured. The cell culture supernatant was collected. The ascites was collected from the same patient. The exosomes were extracted by ultracentrifugation and ultrafiltration from the cell culture supernatant and the ascites and were examined under electron microscope. HSP70, HSP90, MHC class ¢ñ molecule and MHC class ¢ò molecule on exosomes were tested by Western blotting. The protein concentration of exosomes was tested by BCA method. RESULTS: The time for the centrifugation of ascites was longer than that of supernatant. The exosomes could be obtained from all of the supernatants and the ascites with cancer cells, not from the ascites without cancer cells. The exosomes expressed MHC class ¢ñ molecule, HSP70 and HSP90 except MHC class ¢ò molecule. The protein concentration of exosomes in the ascites was higher than that of the supernantant of cell culture (P<0.05). CONCLUSION: Ascites is a better source of exosomes for the ovarian cancer patient with malignant effusion with positive cancer cells. The exosomes can be extracted from ovarian cancer tissue for the patients without ascites or with ascites in which cancer cells are negative. ......