Open AccessmiR-33a expression sensitizes Lgr5+ HCC-CSCs to doxorubicin via ABCA1
Author(s) -
Hongtao Hou,
Yu-hua Kang,
Y Li,
Yi Zeng,
Guanfu Ding,
Jingmei Shang
Publication year - 2017
Publication title -
neoplasma
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.628
H-Index - 50
eISSN - 1338-4317
pISSN - 0028-2685
DOI - 10.4149/neo_2017_110
Subject(s) - lgr5 , cancer research , cancer stem cell , doxorubicin , ectopic expression , stem cell , microrna , cancer , medicine , biology , cell culture , chemotherapy , microbiology and biotechnology , biochemistry , gene , genetics
Cancer stem cells (CSCs) are responsible for the unrestrained cell growth and chemo-resistance of malignant tumors. Reports about miR-33a in different type of cancer are limited, and it remains elusive whether there is a link between miR-33a and chemo-resistance of CSCs. Here we report that Lgr5+ hepatocellular carcinoma (HCC) cells from primary tissues and cell lines behave similarly to CSCs and are chemo-resistant to doxorubicin. Significantly, reduced miR-33a expression is associated with the chemo-resistance of Lgr5+ HCC-CSCs, accompanied by an overexpression of ABCA1 which is identied as target of miR-33a by mainly using miRNA luciferase assay and western-blotting. We demonstrate that down-regulation of miR-33a expression directly contributes to chemo-resistance of Lgr5+ HCC-CSCs, and restoring miR-33a expression sensitizes them to doxorubicin via apoptosis by mainly using TUNEL assay, soft agar colony formation assay and xenograft assay. Additionally, reduced miR-33a expression in HCC tissues is associated with chemo-response and poor patient survival, which suggests the therapeutic potential of miR-33a. In conclusion, our work indicates that ectopic miR-33a expression sensitizes Lgr5+ HCC-CSCs to doxorubicin via direct targeting ABCA1, which sheds new light on understanding the mechanism of chemo-resistance in HCC-CSCs and contributes to development of potential therapeutics against HCC.