miRNome Profiling and Functional Analysis Reveal Involvement of hsa-miR-1246 in Colon Adenoma-Carcinoma Transition by Targeting AXIN2 and CFTR

Abstract

Regulatory changes occurring early in colorectal cancer development remain poorly investigated. Since the majority of cases develop from polyps in the adenoma-carcinoma transition, a search of early molecular features, such as aberrations in miRNA expression occurring prior to cancer development, would enable identification of potentially causal, rather than consequential, candidates in the progression of polyp to cancer. In the current study, by employing small RNA-seq profiling of colon biopsy samples, we described differentially expressed miRNAs and their isoforms in the adenoma-carcinoma transition. Analysis of healthy-adenoma-carcinoma sequence in an independent validation group enabled us to identify early deregulated miRNAs including hsa-miR-1246 and hsa-miR-215-5p, the expressions of which are, respectively, gradually increasing and decreasing. Loss-of-function experiments revealed that inhibition of hsa-miR-1246 lead to reduced cell viability, colony formation, and migration rate, thereby indicating an oncogenic effect of this miRNA in vitro. Subsequent western blot and luciferase reporter assay provided evidence of hsa-miR-1246 being involved in the regulation of target AXIN2 and CFTR genes’ expression. To conclude, the present study revealed possible involvement of hsa-miR-1246 in early colorectal cancer development and regulation of tumor suppressors AXIN2 and CFTR.

Identification of a dysregulated CircRNA-associated gene signature for predicting prognosis, immune landscape, and drug candidates in bladder cancer

“…To identify the DEcircRNAs-DEmiRNAs-DEmRNAs regulatory relationships, we performed the prediction of circRNA-miRNA and miRNA-mRNA interactions based on the popular online tools, and then constructed a ceRNA network following the "ceRNA network hypothesis". In this ceRNA network, previous studies have confirmed that miR-3194-3p/AQP1 (43), miR-1246/AXIN2 (44), miR-326/E2F2 (45), miR-326/CDCA5 (46), and miR-17-3p/RGS2 (47), etc, interaction relations play important roles in the occurrence and development of various cancers. Notably, these researches also to some extent reflect the veracity of the predicted ceRNA network in the current study.…”

Circulating miRNA Expression Profiles and Machine Learning Models in Association with Response to Irinotecan-Based Treatment in Metastatic Colorectal Cancer

“…Out of the top 20 miRNAs that were found to be differentially expressed in our samples, several of them have previously been linked with CRC [30][31][32]. Therefore, in line with previous observations, hsa-miR-155-5p [33,34], hsa-let-7i-5p [35], hsa-miR-92a-3p [36], hsa-miR-181d-5p [37], hsa-miR181b-5p [38], hsa-miR-10b-5p [39], hsa-let-7f-5p [40], and hsa-miR-181a-5p [41] were found to be upregulated in our cohort, whereas hsa-miR-215-5p [36,42], hsa-miR-143-3p [43,44], hsa-miR-148a-3p [45], hsa-miR-17-5p [46], hsa-miR-10a-5p [43], and hsa-let-7a-5p [47] were found to be downregulated. These miRNAs directly target critical genes in colorectal carcinogenesis and prognosis, such as PTEN [39], TUSC3 [38], PAI-1, AXIN2, CTFR [42], and predominant biological pathways such as the TGF-β signaling pathway, as well as microsatellite instability [33].…”

5′-Isoforms of miR-1246 Have Distinct Targets and Stronger Functional Impact Compared with Canonical miR-1246 in Colorectal Cancer Cells In Vitro

“…Within the framework of this study, we chose to analyze the 5′-isomiRs of miR-1246, which have been reported by our group to be deregulated in the early stages of colorectal carcinogenesis [ 19 ]. Although a considerable amount of functional (basic and clinical) and regulatory information is known about the canonical oncogenic miR-1246, there is no knowledge of the possible target genes of its isoforms or their functional roles.…”

“…A number of array-based, targeted, and high-throughput sequencing studies have shown the importance of miRNAs in CRC and have evaluated their suitability for diagnostic or prognostic purposes [ 18 ]. Recently, our group performed miRnome profiling in a colon adenoma–carcinoma sequence and identified miR-1246 to be deregulated in the early carcinogenesis [ 19 ]. Furthermore, we identified that ISO-miR-1246_a and ISO-miR-1246_G were more deregulated in CRC patients’ colon tissue compared with that of healthy controls ( Supplementary Figure S1 ).…”