TY - JOUR
T1 - Cancer stem-like sphere cells induced from de-differentiated hepatocellular carcinoma-derived cell lines possess the resistance to anti-cancer drugs
AU - Hashimoto, Noriaki
AU - Tsunedomi, Ryouichi
AU - Yoshimura, Kiyoshi
AU - Watanabe, Yusaku
AU - Hazama, Shoichi
AU - Oka, Masaaki
PY - 2014/9/27
Y1 - 2014/9/27
N2 - Background: Cancer stem cells (CSCs) are thought to play important roles in therapy-resistance. In this study, we induced cancer stem-like cells from hepatocellular carcinoma (HCC) cell lines using a unique medium, and examined their potential for resistance to anti-cancer drugs.Methods: The human HCC cell lines SK-HEP-1 (SK), HLE, Hep 3B, and HuH-7 were used to induce cancer stem-like cells with our sphere induction medium supplemented with neural survival factor-1. NANOG and LIN28A were examined as stemness markers. Several surface markers for CSC such as CD24, CD44, CD44 variant, and CD90 were analyzed by flow-cytometry. To assess the resistance to anti-cancer drugs, the MTS assay, cell cycle analysis, and reactive oxygen species (ROS) activity assay were performed. Results: Poorly differentiated HCC derived SK and undifferentiated HCC derived HLE cell lines efficiently formed spheres of cells (SK-sphere and HLE-sphere), but well-differentiated HCC-derived HuH-7 and Hep 3B cells did not. SK-spheres showed increased NANOG, LIN28A, and ALDH1A1 mRNA levels compared to parental cells. We observed more CD44 variant-positive cells in SK-spheres than in parental cells. The cell viability of SK-spheres was significantly higher than that of SK cells in the presence of several anti-cancer drugs except sorafenib (1.7- to 7.3-fold, each P <0.05). The cell cycle of SK-spheres was arrested at the G0/G1 phase compared to SK cells. SK-spheres showed higher ABCG2 and HIF1A mRNA expression and lower ROS production compared to parental cells.Conclusion: Our novel method successfully induced cancer stem-like cells, which possessed chemoresistance that was related to the cell cycle, drug efflux, and ROS.
AB - Background: Cancer stem cells (CSCs) are thought to play important roles in therapy-resistance. In this study, we induced cancer stem-like cells from hepatocellular carcinoma (HCC) cell lines using a unique medium, and examined their potential for resistance to anti-cancer drugs.Methods: The human HCC cell lines SK-HEP-1 (SK), HLE, Hep 3B, and HuH-7 were used to induce cancer stem-like cells with our sphere induction medium supplemented with neural survival factor-1. NANOG and LIN28A were examined as stemness markers. Several surface markers for CSC such as CD24, CD44, CD44 variant, and CD90 were analyzed by flow-cytometry. To assess the resistance to anti-cancer drugs, the MTS assay, cell cycle analysis, and reactive oxygen species (ROS) activity assay were performed. Results: Poorly differentiated HCC derived SK and undifferentiated HCC derived HLE cell lines efficiently formed spheres of cells (SK-sphere and HLE-sphere), but well-differentiated HCC-derived HuH-7 and Hep 3B cells did not. SK-spheres showed increased NANOG, LIN28A, and ALDH1A1 mRNA levels compared to parental cells. We observed more CD44 variant-positive cells in SK-spheres than in parental cells. The cell viability of SK-spheres was significantly higher than that of SK cells in the presence of several anti-cancer drugs except sorafenib (1.7- to 7.3-fold, each P <0.05). The cell cycle of SK-spheres was arrested at the G0/G1 phase compared to SK cells. SK-spheres showed higher ABCG2 and HIF1A mRNA expression and lower ROS production compared to parental cells.Conclusion: Our novel method successfully induced cancer stem-like cells, which possessed chemoresistance that was related to the cell cycle, drug efflux, and ROS.
KW - Cancer stem cell
KW - Chemoresistance
KW - HCC
KW - Sphere
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U2 - 10.1186/1471-2407-14-722
DO - 10.1186/1471-2407-14-722
M3 - Article
C2 - 25260650
AN - SCOPUS:84908082440
SN - 1471-2407
VL - 14
JO - BMC Cancer
JF - BMC Cancer
IS - 1
M1 - 722
ER -