Abstract 3055: A model of CSC converted from iPSC in the conditioned medium of HCC paving the way to establish HCC CSC

• Published in: Cancer research (Chicago, Ill.) Ill.), 2018-07, Vol.78 (13_Supplement), p.3055-3055
• Main Authors: Afify, Said M, Calle, Anna Sanchez, Kumon, Kazuki, Nawara, Hend M, Khairani, Apriliana C, Mahmud, Hafizah, Oo, Aung Ko Ko, Juan, Du, Zahara, Maram H, Seno, Akimasa, Kasai, Tomonari, Iwasaki, Yoshiaki, Seno, Masaharu
• Format: Article
• Language: eng ; jpn
• ISSN: 0008-5472; 1538-7445
• DOI: 10.1158/1538-7445.AM2018-3055

Hepatocellular carcinoma (HCC) represents the major histological subtype, accounting for 70%–85% of cases of primary liver cancer. Liver CSCs sustain their self-renewal remains largely unknown. The self-renewal and pluripotency of liver CSC are maintained by several signaling cascades. However, the mechanism of regulating these signaling is unknown. In this study, we tried to convert mouse iPSCs into CSCs with the conditioned medium (CM) from human HCC cell line Huh7 cells without any genetic manipulation aiming at establishing liver CSCs. First of all, CM was collected from confluent culture of Huh7 cells. Then, mouse iPSCs cells without MEF feeder cells were cultured in the presence of 50% CM for 4 weeks. The medium was changed every day with fresh medium containing 50% of CM. Mouse iPSCs cultured in the complete medium with LIF were used as a control.The survived cells (5x105 cells) were suspended in HBSS and injected into the liver of BALB/c nude mice. After 25 days malignant tumor was formed in the liver while benign teratoma was formed by the injection of iPSCs. Tumors were then excised and partly fixed in 10% neutral formalin buffer solution for HE staining and immunohistochemical analysis. The rest of tumors were subjected to rt-qPCR anaylsis and primary culture. Immunohistochemical analysis with GFP antibody showed that malignant tumor sustained GFP expression while teratoma from miPSCs did not. Immunocytochemistry of the primary cells from malignant tumor showed high expression of both glypican-3 (GPC3) and cytokeratin19 (CK19) when compared to that in miPSCs. Expression of stem cell markers (Nanog, Oct3/4, Sox2, Klf4) and CSC markers (CD44, EpCAM) were also confirmed by rt-qPCR in both the CSCs converted from iPSCs (miPS-Huh7cm cells) and the primary culture cells. These results indicate that the primary cells from the malignant tumor are rich in CSCs with high expression of GPC3 and CK19, which paves the way to establish a model of HCC CSC. This model should be very important and useful to assess the significant molecular mechanisms necessary to maintain HCC CSC, which will help develop effective therapy of liver cancer. Citation Format: Said M Afify, Anna Sanchez Calle, Kazuki Kumon, Hend M Nawara, Apriliana C Khairani, Hafizah Mahmud, Aung Ko Ko Oo, Du Juan, Maram H Zahara, Akimasa Seno, Tomonari Kasai, Yoshiaki Iwasaki, Masaharu Seno. A model of CSC converted from iPSC in the conditioned medium of HCC paving the way to establish HCC CSC [abs