Long Noncoding RNA MPRL Promotes Mitochondrial Fission and Cisplatin Chemosensitivity via Disruption of Pre-miRNA Processing.

The overall biological roles and clinical significance of most long noncoding RNAs (lncRNA) in chemosensitivity are not fully understood. We investigated the biological function, mechanism, and clinical significance of lncRNA NR_034085, which we termed miRNA processing-related lncRNA (MPRL), in tongue squamous cell carcinoma (TSCC). LncRNA expression in TSCC cell lines with cisplatin treatment was measured by lncRNA microarray and confirmed in TSCC tissues. The functional roles of MPRL were demonstrated by a series of in vitro and in vivo experiments. The miRNA profiles, RNA pull-down, RNA immunoprecipitation, serial deletion analysis, and luciferase analyses were used to investigate the potential mechanisms of MPRL. We found that MPRL expression was significantly upregulated in TSCC cell lines treated with cisplatin and transactivated by E2F1. MPRL controlled mitochondrial fission and cisplatin sensitivity through miR-483-5p. In exploring the underlying interaction between MPRL and miR-483-5p, we identified that cytoplasmic MPRL directly binds to pre-miR-483 within the loop region and blocks pre-miR-483 recognition and cleavage by TRBP-DICER-complex, thereby inhibiting miR-483-5p generation and upregulating miR-483-5p downstream target-FIS1 expression. Furthermore, overexpression or knockdown MPRL altered tumor apoptosis and growth in mouse xenografts. Importantly, we found that high expression of MPRL and pre-miR-483, and low expression of miR-483-5p were significantly associated with neoadjuvant chemosensitivity and better TSCC patients' prognosis. We propose a model in which lncRNAs impair microprocessor recognition and are efficient of pre-miRNA cropping. In addition, our study reveals a novel regulatory network for mitochondrial fission and chemosensitivity and new biomarkers for prediction of neoadjuvant chemosensitivity in TSCC.These findings uncover a novel mechanism by which lncRNA determines mitochondrial fission and cisplatin chemosensitivity by inhibition of pre-miRNA processing and provide for the first time the rationale for lncRNA and miRNA biogenesis for predicting chemosensitivity and patient clinical prognosis.

Tian T ，Lv X ，Pan G ，Lu Y ，Chen W ，He W ，Lei X ，Zhang H ，Liu M ，Sun S ，Ou Z ，Lin X ，Cai L ，He L ，Tu Z ，Wang X ，Tannous BA ，Ferrone S ，Li J ，Fan S ... -  《-》

miR-483-5p determines mitochondrial fission and cisplatin sensitivity in tongue squamous cell carcinoma by targeting FIS1.

Fan S ，Chen WX ，Lv XB ，Tang QL ，Sun LJ ，Liu BD ，Zhong JL ，Lin ZY ，Wang YY ，Li QX ，Yu X ，Zhang HQ ，Li YL ，Wen B ，Zhang Z ，Chen WL ，Li JS ... -  《-》

Mitochondrial fission determines cisplatin sensitivity in tongue squamous cell carcinoma through the BRCA1-miR-593-5p-MFF axis.

Fan S ，Liu B ，Sun L ，Lv XB ，Lin Z ，Chen W ，Chen W ，Tang Q ，Wang Y ，Su Y ，Jin S ，Zhang D ，Zhong J ，Li Y ，Wen B ，Zhang Z ，Yang P ，Zhou B ，Liang Q ，Yu X ，Zhu Y ，Hu P ，Chu J ，Huang W ，Feng Y ，Peng H ，Huang Q ，Song E ，Li J ... -  《Oncotarget》

Actin filament-associated protein 1-antisense RNA1 promotes the development and invasion of tongue squamous cell carcinoma via the AFAP1-AS1/miR-133a-5p/ZIC2 axis.

The present study aimed to explore the biological role and underlying mechanism of the long non-coding RNA actin filament-associated protein 1-antisense RNA1 (lncRNA AFAP1-AS1) in the progression of tongue squamous cell carcinoma (TSCC). A quantitative reverse transcriptase-PCR (RT-qPCR) was conducted to assess relative levels of the miR-133a-5p, lncRNAs AFAP1-AS1 and zinc finger family member 2 (ZIC2) in TSCC cell lines and specimens, whereas ZIC2 protein levels were measured using western blotting. After modifying the levels of expression of lncRNA AFP1-AS1, miR-133a-5p and ZIC2 using lentivirus or plasmid transfection, we examined AKT/epithelial-mesenchymal transition signaling pathway alterations, in vivo carcinogenesis of TSCC in nude mice and in vitro malignant phenotypes. A dual-luciferase reporter assay was conducted to confirm the targeting relationship between ZIC2 and miR-133a-5p, as well as between miR-133a-5p and lncRNA AFAP1-AS1. Based on The Cancer Genome Atlas (TCGA) database, we additionally validated AFP1-AS1. The potential biological pathway for AFP1-AS1 was investigated using gene set enrichment analysis (GSEA). We also evaluated the clinical diagnostic capacities of AFP1-AS1 and clustered the most potential biomarkers with the Mfuzz expression pattern. Finally, we also made relevant drug predictions for AFP1-AS1. In TSCC cell lines and specimens, lncRNA AFAP1-AS1 was upregulated. ZIC2 was upregulated in TSCC cells as a result of lncRNA AFAP1-AS1 overexpression, which also promoted TSCC cell migration, invasion, viability, and proliferation. Via the microRNA sponge effect, it was found that lncRNA AFAP1-AS1 could upregulate ZIC2 by competitively inhibiting miR-133a-5p. Interestingly, knockdown of ZIC2 reversed the biological roles of lncRNA AFAP1-AS1 with respect to inducing malignant phenotypes in TSCC cells. In addition, in vivo overexpression of lncRNA AFAP1-AS1 triggered subcutaneous tumor growth in nude mice implanted with TSCC cells and upregulated ZIC2 in the tumors. The TCGA database findings revealed that AFAP1-AS1 was significantly upregulated in TSCC specimens and had good clinical diagnostic value. The results of GSEA showed that peroxisome proliferator-activated receptor signaling pathway was significantly correlated with low expression of AFP1-AS1. Finally, the results of drug prediction indicated that the group with high AFAP1-AS1 expression was more sensitive to docetaxel, AZD4547, AZD7762 and nilotinib. The upregulation of lncRNA AFAP1-AS1, which increases TSCC cell viability, migration, proliferation and invasion via the AFAP1-AS1/miR-133a-5p/ZIC2 axis, aids in the progression of TSCC.

Tang M ，Wu H ，Zhang H ，Xu X ，Jiang B ，Chen Q ，Wei Y ，Qian H ，Han L ... -  《-》

LncRNA KCNQ1OT1 contributes to the cisplatin resistance of tongue cancer through the KCNQ1OT1/miR-124-3p/TRIM14 axis.

Qiao CY ，Qiao TY ，Jin H ，Liu LL ，Zheng MD ，Wang ZL ... -  《-》