title: MicroRNA-522 reverses drug resistance of doxorubicin-induced HT29 colon cancer cell by targeting ABCB5.
abstract: MicroRNAs (miRNAs) are small non-coding RNAs, which are important in the development of multidrug resistance in cancer by regulating gene expression at the post‑transcriptional level. The present study investigated the functional effects of miR‑522 in chemoresistant colon cancer cells. The results demonstrated that miR‑522 was significantly downregulated in doxorubicin (DOX) resistant colon cell line, HT29/DOX, compared with the parental HT29 colon cancer cell line. Overexpression of miR‑522 in the HT29/DOX cells partially restored DOX sensitivity. miRNA target prediction algorithms suggested that ABCB5 was a target gene for miR‑522. A fluorescent reporter assay confirmed that miR‑522 was able to specifically bind to the predicted site of the ABCB5 mRNA 3'‑untranslated region. When miR‑522 was overexpressed in the HT29/DOX cells, the protein expression levels of ABCB5 were downregulated. Furthermore, knockdown of ABCB5 significantly increased the growth inhibition rate of the HT29/DOX cells, compared with the control group. These results suggested that miR‑522 may affect the sensitivity of colon cancer cell lines to DOX treatment by targeting ABCB5.
authors.affiliation: Clinical Laboratory, Affiliated Second People's Hospital of Luzhou Medical College, Neijiang, Sichuan 641000, P.R. China.
authors.forename: Ge
authors.initials: G
authors.lastname: Yang
authors.affiliation: Clinical Laboratory, Affiliated Second People's Hospital of Luzhou Medical College, Neijiang, Sichuan 641000, P.R. China.
authors.forename: Ou
authors.initials: O
authors.lastname: Jiang
authors.affiliation: Clinical Laboratory, Affiliated Second People's Hospital of Luzhou Medical College, Neijiang, Sichuan 641000, P.R. China.
authors.forename: Daiqiong
authors.initials: D
authors.lastname: Ling
authors.affiliation: Clinical Laboratory, Affiliated Second People's Hospital of Luzhou Medical College, Neijiang, Sichuan 641000, P.R. China.
authors.forename: Xiaoyue
authors.initials: X
authors.lastname: Jiang
authors.affiliation: Clinical Laboratory, Affiliated Second People's Hospital of Luzhou Medical College, Neijiang, Sichuan 641000, P.R. China.
authors.forename: Pingzong
authors.initials: P
authors.lastname: Yuan
authors.affiliation: Clinical Laboratory, Affiliated Second People's Hospital of Luzhou Medical College, Neijiang, Sichuan 641000, P.R. China.
authors.forename: Guang
authors.initials: G
authors.lastname: Zeng
authors.affiliation: Key Laboratory of Diagnostic Medicine Designated by the Chinese Ministry of Education and School of Diagnostic Medicine, Chongqing Medical University, Chongqing 400016, P.R. China.
authors.forename: Jing
authors.initials: J
authors.lastname: Zhu
authors.affiliation: Key Laboratory of Diagnostic Medicine Designated by the Chinese Ministry of Education and School of Diagnostic Medicine, Chongqing Medical University, Chongqing 400016, P.R. China.
authors.forename: Jie
authors.initials: J
authors.lastname: Tian
authors.affiliation: Key Laboratory of Diagnostic Medicine Designated by the Chinese Ministry of Education and School of Diagnostic Medicine, Chongqing Medical University, Chongqing 400016, P.R. China.
authors.forename: Yaguang
authors.initials: Y
authors.lastname: Weng
authors.affiliation: Clinical Laboratory, Affiliated Second People's Hospital of Luzhou Medical College, Neijiang, Sichuan 641000, P.R. China.
authors.forename: Daoquan
authors.initials: D
authors.lastname: Wu
mesh_terms: D020413:3' Untranslated Regions; D018435:ATP Binding Cassette Transporter, Subfamily B; D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D000903:Antibiotics, Antineoplastic / Q000494:pharmacology; D001483:Base Sequence; D003110:Colonic Neoplasms / Q000378:metabolism / Q000503:physiopathology; D015536:Down-Regulation / Q000187:drug effects*; D004317:Doxorubicin / Q000633:toxicity*; D019008:Drug Resistance, Neoplasm / Q000187:drug effects; D017930:Genes, Reporter; D019073:HT29 Cells; D006801:Humans; D035683:MicroRNAs / Q000037:antagonists & inhibitors / Q000235:genetics / Q000494:pharmacology*; D016376:Oligonucleotides, Antisense / Q000378:metabolism; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D016415:Sequence Alignment
chemical_list: D020413:3' Untranslated Regions; C480744:ABCB5 protein, human; D018435:ATP Binding Cassette Transporter, Subfamily B; D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000903:Antibiotics, Antineoplastic; D035683:MicroRNAs; D016376:Oligonucleotides, Antisense; D034741:RNA, Small Interfering; D004317:Doxorubicin