2A). In addition, MHCC97-L and MHCC97-H cells displayed a higher capacity of tumor sphere formation (Supporting Fig. 2B). Furthermore, MHCC97-L and MHCC97-H cells demonstrated increased expression of ABCG2 and CD44 (Supporting Fig. 2C). Flow cytometry analysis confirmed that CD44 expression in Huh7, Hep3B, MHCC97-L, and MHCC97-H cells was 4.6 ± 1.1%, 3.0 ± 4.2%, 76.9 ± 13.5%, and 97.6 ± 2.3%, respectively. There was no significant difference in Oct4 and Nanog gene expression between the four lines (data not shown). Interestingly, CD133 and EpCAM were highly expressed in Huh7 and Hep3B cells but were essentially undetectable in MHCC97-L and MHCC97-H cells (Supporting Fig.
2C), and CD133 expression in Huh7, Hep3B, MHCC97-L, and MHCC97-H cells demonstrated by way of flow cytometry analysis was 49.7 ± 1.1%, 92.7 ± 1.3%, 0.4 ± 0.8%, and 0.1 ± 0.5%, respectively. In terms of tumor formation in vivo, mesenchymal MHCC97-L and MHCC97-H cells were more tumorigenic MAPK Inhibitor Library in vitro than epithelial Huh7 and Hep3B cells (Supporting Table 2). c-Met inhibitor treatment blocked tumor sphere formation and suppressed CD44 expression in MHCC97-L and MHCC97-H cells
(Supporting Fig. 3). c-Met inhibition PD0325901 order did not alter the low CD133 and EpCAM expression in the MHCC97-L and MHCC97-H cell lines, nor did it change the relatively high level of CD133 expression in epithelial Huh7 and Hep3B cells (Supporting Fig. 3). Interestingly, c-Met inhibitor treatment in MHCC97-L and MHCC97-H cells resulted in increased E-cadherin and decreased fibronectin expression, indicating a potential transition to an epithelial state (Supporting Fig. 4A-C). Although there was no correlation of CSC phenotype to CD133 or EpCAM, these results indicate a potential link between mesenchymal status and some CSC characteristics (such as tumor sphere formation and tumor initiation) in HCC. Given the association of c-Met with poor prognosis selleck inhibitor in HCC,4-7 the primary purpose of this report was to determine the response of multiple c-Met–positive and c-Met–negative HCC cell lines to c-Met inhibition therapy.
The mesenchymal MHCC97-L and MHCC97-H cells demonstrate active c-Met signaling compared with epithelial Huh7 and Hep3B cells, which are c-Met–negative. Based on in vitro and in vivo work, we observed a significant and favorable response to c-Met inhibition of c-Met–positive HCC, with increased apoptosis, decreased proliferation, and suppressed tumor growth. Interestingly, within the MHCC97-L– and MHCC97-H–derived tumors, c-Met–positive, phospho–c-Met–reduced cells survived the c-Met inhibition treatment. Future work is ongoing to determine the mechanism of this c-Met–independent survival. Based on our findings, we propose that c-Met inhibition may be a valuable treatment modality/adjunct for HCC patients with c-Met–positive tumors. Currently, clinical trials with ARQ197, a small molecule c-Met inhibitor, include patients who have failed prior HCC therapy.