Open AccessPositive Feedback Loop of OCT4 and c‐JUN Expedites Cancer Stemness in Liver Cancer
Author(s) -
Kuo KungKai,
Lee KingTeh,
Chen KerKong,
Yang YaHan,
Lin YingChu,
Tsai MingHo,
Wuputra Kenly,
Lee YenLiang,
Ku ChiaChen,
Miyoshi Hiroyuki,
Nakamura Yukio,
Saito Shigeo,
Wu ChunChieh,
Chai CheeYin,
Eckner Richard,
Steve Lin ChenLung,
Wang Sophie SW,
Wu DengChyang,
Lin ChangShen,
Yokoyama Kazunari K.
Publication year - 2016
Publication title -
stem cells
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.159
H-Index - 229
eISSN - 1549-4918
pISSN - 1066-5099
DOI - 10.1002/stem.2447
Subject(s) - biology , homeobox protein nanog , transactivation , oncogene , cancer research , cancer stem cell , carcinogenesis , cancer , gene knockdown , stem cell , induced pluripotent stem cell , liver cancer , cancer cell , c jun , embryonic stem cell , microbiology and biotechnology , transcription factor , cell culture , cell cycle , gene , genetics , hepatocellular carcinoma
A bstract The network of stemness genes and oncogenes in human patient‐specific reprogrammed cancer stem cells (CSCs) remains elusive, especially in liver cancer. HepG2‐derived induced pluripotent stem cell‐like cells (HepG2‐iPS‐like cells) were generated by introducing Yamanaka factors and the knockdown vector shTP53. They exhibited features of stemness and a higher tumorigenesis after xenograft transplantation compared with HepG2 cells. The cancerous mass of severe combined immunodeficiency (SCID) mice derived from one colony was dissected and cultured to establish reprogrammed HepG2‐derived CSC‐like cells (designated rG2‐DC‐1C). A single colony exhibited 42% occurrence of tumors with higher proliferation capacities. rG2‐DC‐1C showed continuous expression of the OCT4 stemness gene and of representative tumor markers, potentiated chemoresistance characteristics, and invasion activities. The sphere‐colony formation ability and the invasion activity of rG2‐DC‐1C were also higher than those of HepG2 cells. Moreover, the expression of the OCT4 gene and the c‐JUN oncogene, but not of c‐MYC , was significantly elevated in rG2‐DC‐1C, whereas no c‐JUN expression was observed in HepG2 cells. The positive‐feedback regulation via OCT4‐mediated transactivation of the c‐JUN promoter and the c‐JUN‐mediated transactivation of the OCT4 promoter were crucial for promoting cancer development and maintaining cancer stemness in rG2‐DC‐1C. Increased expression of OCT4 and c‐JUN was detected in the early stage of human liver cancer. Therefore, the positive feedback regulation of OCT4 and c‐JUN, resulting in the continuous expression of oncogenes such as c‐JUN , seems to play a critical role in the determination of the cell fate decision from iPS cells to CSCs in liver cancer. S tem C ells 2016;34:2613–2624