Modulation of Biliary Cancer Chemo‐Resistance Through MicroRNA‐Mediated Rewiring of the Expansion of CD133+ Cells

Abstract

BaCKgRoUND aND aIMS: Changes in single micro-RNA (miRNA) expression have been associated with chemoresistance in biliary tract cancers (BTCs). However, a global assessment of the dynamic role of the microRNome has never been performed to identify potential therapeutic targets that are functionally relevant in the BTC cell response to chemotherapy. appRoaCH aND ReSUltS: High-throughput screening (HTS) of 997 locked nucleic acid miRNA inhibitors was performed in six cholangiocarcinoma cell lines treated with cisplatin and gemcitabine (CG) seeking changes in cell viability. Validation experiments were performed with mir-Vana probes. MicroRNA and gene expression was assessed by TaqMan assay, RNA-sequencing, and in situ hybridization in four independent cohorts of human BTCs. Knockout of microRNA was achieved by CRISPR-CAS9 in CCLP cells (MIR1249KO) and tested for effects on chemotherapy sensitivity in vitro and in vivo. HTS revealed that MIR1249 inhibition enhanced chemotherapy sensitivity across all cell lines. MIR1249 expression was increased in 41% of cases in human BTCs. In validation experiments, MIR1249 inhibition did not alter cell viability in untreated or dimethyl sulfoxidetreated cells; however, it did increase the CG effect. MIR1249 expression was increased in CD133+ biliary cancer cells freshly isolated from the stem cell niche of human BTCs as well as in CD133+ chemo-resistant CCLP cells. MIR1249 modulated the chemotherapy-induced enrichment of CD133+ cells by controlling their clonal expansion through the Wnt-regulator FZD8. MIR1249KO cells had impaired expansion of the CD133+ subclone and its enrichment after chemotherapy, reduced expression of cancer stem cell markers, and increased chemosensitivity. MIR1249KO xenograft BTC models showed tumor shrinkage after exposure to weekly CG, whereas wildtype models showed only stable disease over treatment. CoNClUSIoNS: MIR1249 mediates resistance to CG in BTCs and may be tested as a target for therapeutics. (Hepatology 2020;0:1-15). B iliary tract cancers (BTCs) include cholangiocarcinoma (CCA) and gallbladder cancer, and their incidence is increasing worldwide. (1-4) Lack of effective radical treatments and rapid failure of palliative ones highlight the need for a better understanding of BTC biology and mechanisms of response to treatment. (2,5) Eighty percent of patients

The Pervasive Role of the miR-181 Family in Development, Neurodegeneration, and Cancer

“…The implication of miR-181a, b, and d in chemically-induced hepatocarcinogenesis has been assessed also by Song and colleagues, who showed that this miRNA family plays a critical role in chemically-induced hepatocarcinogenesis by targeting MKP-5 and regulating the p38 MAPK activation [41]. In a recent study aimed at analyzing the functional roles of the miRNome in intra-hepatic and extra-hepatic bile duct cancer, no impact on cell tumor growth was observed after the miR-181 inhibition of miR-181 family members [65].…”

MicroRNA‑640 promotes cell proliferation and adhesion in glioblastoma by targeting Slit guidance ligand 1

“…Regarded as small non-coding single-stranded RNAs encoded by an endogenous gene, microRNAs (miRNAs/miRs) were discovered to play crucial regulatory roles in the development of cancer by regulating mRNA degradation or translational inhibition of downstream target genes (10)(11)(12). Previous studies have reported that miRNAs act as tumor suppressors or promoters in the abnormal biological process of glioblastoma (13)(14)(15).…”

The Emerging Role of MicroRNAs in Regulating the Drug Response of Cholangiocarcinoma

“…In intrahepatic CCA tissues, miR-1249 was overexpressed in tumor tissues compared with adjacent normal tissues [ 24 ]. Cases with higher miR-1249 were associated with worse prognosis, independently of adjuvant chemotherapy.…”

“…FZD8 could act as a negative regulator of the canonical Wnt pathway by activating the noncanonical Wnt/calcium pathway [ 86 ]. Altogether, miR-1249 mediated the expansion of CD133+ CCA cells with chemoresistance, by targeting FZD8/Wnt signaling [ 24 ].…”