Loss of FoxA2 accelerates neoplastic changes in the intrahepatic bile duct partly via the MAPK signaling pathway
AGING-US
Authors: Shen, Junyi; Zhou, Yongjie; Zhang, Xiaoyun; Peng, Wei; Peng, Chihan; Zhou, Qiang; Li, Chuan; Wen, Tianfu; Shi, Yujun
Abstract
Background: Intrahepatic cholangiocarcinoma (ICC) is characterized by a highly aggressive nature and a dismal outcome. FOXA2 is an archetypal transcription factor involved in cholangiocyte proliferation. Results: FOXA2 expression was negatively correlated with tumor stage (p = 0.024). Univariate and multivariate analyses showed that low FoxA2 expression was associated with tumor relapse and survival. At 20 weeks after TAA administration, FoxA2(-/-) mice displayed significant manifestations of neoplasia, while WT mice did not. RNA sequencing analysis showed that the expression of genes in the MAPK signaling pathway was significantly higher in FoxA2(-/-) mice. IHC and Western blot results showed that p-ERK1/2, CREB1 and RAS were highly expressed in FoxA2(-/-) mice. Furthermore, using in vitro experiments with siRNA, we found that low expression of FoxA2 could exacerbate the metastatic potential of ICC. The expression of p-ERK1/2 and RAS, which are key mediators of the MAPK signaling pathway, was significantly increased. Conclusion: Low FOXA2 expression negatively affected the prognosis of patients with ICC. Loss of FoxA2 expression could promote intrahepatic bile duct neoplasia partly via activation of the MAPK signaling pathway. Materials and methods: In all, the data of 85 patients with ICC were retrospectively collected and analyzed. TAA was used to induce ICC in FoxA2(-/-) mice and WT mice. RNA-sequencing analysis was used to identify the expression of different genes.
Hepatic population derived from human pluripotent stem cells is effectively increased by selective removal of undifferentiated stem cells using YM155
STEM CELL RESEARCH & THERAPY
Authors: Kang, Seok-Jin; Park, Young-Il; Hwang, So-Ryeon; Yi, Hee; Tham, Nga; Ku, Hyun-Ok; Song, Jae-Young; Kang, Hwan-Goo
Abstract
Background: Pluripotent stem cells (PSCs) such as embryonic stem cells and induced pluripotent stem cells are promising target cells for cell regenerative medicine together with recently advanced technology of in-vitro differentiation. However, residual undifferentiated stem cells (USCs) during in-vitro differentiation are considered a potential risk for development of cancer cells and nonspecific lineage cell types. In this study we observed that USCs still exist during hepatic differentiation, consequently resulting in poor quality of the hepatic population and forming teratoma in vivo. Therefore, we hypothesized that effectively removing USCs from in-vitro differentiation could improve the quality of the hepatic population and guarantee safety from risk of teratoma formation. Methods: Human PSCs were differentiated to hepatocytes via four steps. YM155, a known BIRC5 inhibitor, was applied for removing the residual USCs on the hepatic differentiation. After YM155 treatment, hepatocyte development was evaluated by measuring gene expression, immunostaining and hepatic functions at each stage of differentiation, and forming teratomas were confirmed by cell transplantation with or without YM155. Results: The selected concentrations of YM155 removed USCs (NANOG(+) and OCT4(+)) in a dose-dependent manner. As a result, expression of endodermal markers (SOX17, FOXA2 and CXCR4) at stage II of differentiation and hepatic markers (ALB, AFP and HNF4A) at stage III was up-regulated by YM155 treatment as well as the hepatic population (ALB(+)), and functions (ALB/urea secretion and CYP450 enzyme activity) were enhanced at the final stage of differentiation (stage IV). Furthermore, we demonstrated that NANOG and OCT4 expression remaining until stage III (day 15 of differentiation) completely disappeared when treated with YM155 and teratoma formation was effectively prevented by YM155 pretreatment in the in-vitro study. Conclusions: We suggest that the removal of USCs using YM155 could improve the quantity and quality of induced hepatocytes and eliminate the potential risk of teratoma formation.