Long non-coding RNA NNT-AS1 promotes cholangiocarcinoma cells proliferation and epithelial-to-mesenchymal transition through down-regulating miR-203

Abstract

Background: Cholangiocarcinoma (CCA) is a serious malignant tumor. Long non-coding RNA NNT-AS1 (NNT-AS1) takes crucial roles in several tumors. So, we planned to research the roles and underlying mechanism of NNT-AS1 in CCA. Results: NNT-AS1 overexpression was appeared in CCA tissues and cell lines. Proliferation was promoted by NNT-AS1 overexpression in CCLP1 and TFK1 cells. Besides, NNT-AS1 overexpression reduced E-cadherin level and raised levels of N-cadherin, vimentin, Snail and Slug. However, the opposite trend was occurred by NNT-AS1 knockdown. Further, NNT-AS1 overexpression promoted phosphatidylinositol 3 kinase (PI3K)/AKT and extracellular signal-regulated kinase (ERK)1/2 pathways. MiR-203 was sponged by NNT-AS1 and miR-203 mimic reversed the above promoting effects of NNT-AS1. Additionally, insulin-like growth factor type 1 receptor (IGF1R) and zinc finger E-box binding homeobox 1 (ZEB1) were two potential targets of miR-203. Conclusion: NNT-AS1 promoted proliferation, EMT and PI3K/AKT and ERK1/2 pathways in CCLP1 and TFK1 cells through down-regulating miR-203. Methods: CCLP1 and TFK1 cells were co-transfected with pcDNA-NNT-AS1 and miR-203 mimic. Bromodeoxyuridine (BrdU), flow cytometry, quantitative reverse transcription polymerase chain reaction (qRT-PCR) and western blot were employed to detect roles and mechanism of NNT-AS1. Interaction between NNT-AS1 and miR-203 or miR-203 and target genes was examined through luciferase activity experiment.

The Role of Long Non-Coding RNA NNT-AS1 in Neoplastic Disease

“…Since zinc finger E-box binding homeobox 1 (ZEB1) is a potential target of miR-203, up-regulated NNT-AS1 can significantly increase the phosphorylation level of ERK1/2 and the level of EMT-related protein ZEB1 and reduce the expression of e-cadherin. The above effects can be reversed by miR-203 mimic, indicating the regulatory role of NNT-AS1/miR-203 in the ERK pathway and EMT [23]. In addition, NNT-AS1 can also increase Yes1-associated transcriptional regulator (YAP1) by sponging miR-22-3p, which in turn promotes the proliferation, migration, invasion, and EMT of NSCLC cells.…”

“…These provide evidence that NNT-AS1 is able to activate the PI3K/AKT signaling pathway through the ceRNA mechanism. Besides, IGF1R is a potential target of miR-203 [23]. In CAA cells, the NNT-AS1/miR-203/IGF1R axis has also been found to promote the phosphorylation of PI3K and AKT, which in turn activates the PI3K/AKT signaling pathway [23].…”

“…Current research shows that NNT-AS1 is highly expressed in most tumors, including non-small-cell lung cancer (NSCLC) [ 16 , 17 , 18 , 19 ], lung squamous cell carcinoma (LUSC) [ 20 ], colorectal cancer (CRC) [ 14 ], hepatocellular carcinoma (HCC) [ 21 ], cholangiocarcinoma (CAA) [ 22 , 23 , 24 ], cervical cancer [ 25 , 26 ], osteosarcoma [ 27 , 28 ], bladder cancer [ 29 , 30 ], and glioma [ 31 ]. These results have been verified in the corresponding tumor tissues or tumor cells.…”

NNT-AS1 Impairs CD4+ T Cells Infiltration by Up-Regulating TGF-β Signaling in Hepatocellular Carcinoma

“…Moreover, the signi cance of NNT-AS1 in orchestrating tumourigenesis had been addressed by many other reports. NNT-AS1 promoted cholangiocarcinoma cells proliferation and EMT through down-regulating miR-203 [39]. NNT-AS1 regulated the progression of lung cancer through the NNT-AS1/miR-3666/E2F2 axis [40].…”

Upregulated Expression of LncRNA Nicotinamide Nucleotide Transhydrogenase Antisense RNA 1 is Correlated with Unfavorable Clinical Outcomes in Cancers

“…Moreover, other pathways including PI3K/Akt/mTOR and Wnt/β-catenin signaling pathway were also found involved in the tumorigenesis and progression [26,15]. Besides, NNT-AS1 was capable of serving as a competing endogenous RNA (ceRNA) by sponging miR-485/BCL9 or miR-203 in cholangiocarcinoma [31,32], miR-1301-3p/PODXL or miR-496/HMGB1 in bladder cancer [3,33], miR-142-3p/ZEB1 in breast cancer [19], miR-424/E2F1 or miR-363 in gastric cancer [28,8], miR-22-3p/YAP1 or miR-129-5p in non-small cell lung cancer [34,30], and miR-320a in osteosarcoma [27], therefore alteration in cancer cell function resulting from NNT-AS1 downregulation may be rescued by miRNA inhibition. Notably, NNT-AS1 also showed a high expression level in drug-resistant NSCLC, which promoted the cisplatin resistance of cancer cells via the MAPK/Slug pathway [35].…”