ARID3A and ARID3B exert direct regulatory control over the long non-coding RNAs (lncRNAs) MALAT1 and NORAD within the context of non-small cell lung cancer (NSCLC)

Abstract

Lung cancer, known for its high mortality rates and poor prognosis, remains one of the most prevalent cancer types. Early detection and effective treatment methods are crucial for improving survival rates. Non-small cell lung cancer (NSCLC) accounts for approximately 85 % of all lung cancer cases. Long non-coding RNAs (lncRNAs), which play vital roles in various biological processes, have been implicated in the development of cancer and can impact key therapeutic targets in different cancer types. In NSCLC, the dysregulation of specific lncRNAs, such as MALAT1 and NORAD, has been associated with neoplastic initiation, progression, metastasis, tumor angiogenesis, chemoresistance, and genomic instability. Both MALAT1 and NORAD directly regulate the expression of the transcription factor E2F1, thereby influencing cell cycle progression. Additionally, MALAT1 has been reported to affect the expression of p53 target genes, leading to cell cycle progression through the repression of p53 promoter activity. NORAD, on the other hand, is indirectly regulated by p53. The AT-rich interaction domain (ARID) family of DNA-binding proteins, particularly ARID3A and ARID3B, are involved in various biological processes such as cell proliferation, differentiation, and development. They also play significant roles in E2F-dependent transcription and are transcriptional targets of p53. The intricate balance between promoting cellular proliferation through the pRB-E2F pathway and inducing growth arrest through the p53 pathway underscores the crucial regulatory role of ARID3A, ARID3B, and their interaction with lncRNAs MALAT1 and NORAD. In this study, we aimed to investigate the potential interactive and functional connections among ARID3A, ARID3B, MALAT1, and NORAD in NSCLC, considering their involvement in the pRB-E2F and p53 pathways. Our findings strongly suggest that ARID3A and ARID3B play a regulatory role in controlling MALAT1 and NORAD in NSCLC. Specifically, our study demonstrates that the activities of MALAT1 and NORAD were markedly increased upon the overexpression of ARID3A and ARID3B. Therefore, we can conclude that ARID3A and ARID3B likely contribute significantly to the oncogenic functions of MALAT1 and NORAD in NSCLC. Consequently, targeting ARID3A and ARID3B could hold promise as a therapeutic approach in NSCLC, given their direct control over the expression of MALAT1 and NORAD.