Knockdown of lncRNA ANRIL inhibits the development of cisplatin resistance by upregulating miR‑98 in lung cancer cells

Abstract

Emerging evidence has demonstrated that abnormally expressed long non-coding (lnc) RNAs contribute to drug resistance in various types of malignancy. LncRNA antisense non-coding RNA in the inhibitor of cyclin-dependent kinase 4 locus (ANRIL) exerts oncogenic activity and acts as a key player in a variety of carcinomas, including non-small cell lung cancer. The present study aimed to investigate the functional roles of ANRIL in cisplatin (DDP) resistance of lung cancer and the underlying mechanism involved in the competing endogenous RNA regulatory network. The expression levels of ANRIL and microRNA (miR)-98 in lung cancer tissues and DDP-resistant lung cancer cells were assessed by reverse transcription-quantitative (RT-q) PCR. The Pearson's correlation coefficient was used to determine the correlation between the expression levels of ANRIL and miR-98 in lung cancer tissues. Cell proliferation and apoptosis were detected by MTT assay and flow cytometry analysis, respectively. The expression levels of proliferation-and apoptosis-associated proteins were detected by western blot analysis. The potential interaction between ANRIL and miR-98 was confirmed by RNA immunoprecipitation (RIP), dual luciferase reporter assay and RT-qPCR. The results of the present study demonstrated that ANRIL was upregulated and miR-98 was downregulated in lung cancer tissues and A549/DDP cells. In addition, the Pearson's correlation analysis revealed that the expression of ANRIL was significantly negatively correlated with that of miR-98 in lung cancer tissues. ANRIL overexpression reversed the DDP-induced cell proliferation suppression and apoptosis in lung cancer cells, whereas ANRIL knockdown exhibited the opposite effects. RIP, dual luciferase reporter assay and RT-qPCR analysis results demonstrated that ANRIL directly interacted with miR-98 and suppressed miR-98 expression. Furthermore, transfection with the miR-98 mimics promoted DDP-induced cell proliferation inhibition and apoptosis in lung cancer cells, and these effects were partially reversed by ANRIL overexpression. In conclusion, ANRIL knockdown inhibited the development of DDP resistance by upregulating miR-98, providing novel insights into the molecular mechanism of ANRIL involvement in DDP resistance of lung cancer cells.

Long Non-Coding RNA ANRIL as a Potential Biomarker of Chemosensitivity and Clinical Outcomes in Osteosarcoma

“…Though not statistically significant, SAOS2 ANRIL knockdown cells displayed a predicted trend of decreased proliferation rates under drug-naïve conditions. The effect of ANRIL expression on cancer cell proliferation observed in our study is consistent with previous reports documented in retinoblastoma, liver cancer, gastric cancer and lung cancer [ 30 , 31 , 32 , 33 , 34 , 35 , 36 ]. Additionally, a previous study by Li G. et al showed decreased cell proliferation under drug-naïve conditions and increased cisplatin sensitivity in U2OS cells after ANRIL knockdown [ 34 ].…”

“…Previous studies have shown that ANRIL expression is upregulated in osteosarcoma tissues by comparison to adjacent normal tissues and may play a role in the regulation of cell proliferation, growth, and metastasis of osteosarcoma and other cancer types [ 30 , 31 , 32 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 ]. In relation to chemotherapeutic response, ANRIL has also been reported to promote cell chemoresistance, in multiple cancer types, to various therapeutic agents including cisplatin [ 33 , 34 , 35 , 36 , 37 , 52 , 53 , 54 ].…”

“…However, the underlying mechanisms of this relationship remain unclear, which may require a more comprehensive, longitudinal examination of protein-coding genes, both at the RNA and protein level, after ANRIL modification. Indeed, previous studies have provided evidence for significant relationships with select microRNAs and regulated genes, such as let-7a/HMGA2, miRNA-125a-5p/STAT3, microRNA-98, and microRNA-328/ABCG2, to further elucidate potential mechanisms involved in ANRIL-mediated chemoresistance to cisplatin across different cancer types [ 31 , 32 , 33 , 34 , 35 , 36 , 52 ]. A separate study in oral squamous cell carcinoma also identified significant impairment of drug transporters MRP1 and ABCC2 after ANRIL knockdown, which resulted in increased cisplatin cytotoxicity [ 53 ].…”

“…The lncRNA ANRIL (also known as CDKN2B-AS1 ) was first identified from familial melanoma patients with a large germline deletion in the INK4B-ARF-INK4A gene cluster, and has been previously characterized as an oncogene in osteosarcoma and other cancer types [ 20 , 27 , 28 , 29 , 30 ]. In relation to chemotherapeutic response, previous studies have shown ANRIL to promote cell chemoresistance in multiple cancers; however, the impact of ANRIL in response to cisplatin and doxorubicin in the treatment of osteosarcoma is not fully elucidated [ 20 , 31 , 32 , 33 , 34 , 35 , 36 , 37 ].…”

Advances in the application of Let‑7 microRNAs in the diagnosis, treatment and prognosis of leukemia (Review)

“…In a previous study, Let-7b expression was shown to be lower in the low-risk karyotype AML group and higher in the intermediate or high-risk karyotype AML group ( 51 ). The expression of Let-7 is also related to the drug resistance of leukemia; for example, miR-98 belongs to the Let-7 family, and the overexpression of miR-98 in drug-resistant cells significantly reversed drug resistance ( 52 ). It is speculated that miR-98 may be a potential approach to overcome the drug resistance of leukemia cells.…”