Role of long non-coding RNAs in therapeutic resistance and clinical applications in cancer.

Cancer is one of the leading causes of mortality worldwide and is recognized as a complex, multifactorial disease with no clearly defined etiology for its onset and progression. Long non-coding RNAs (lncRNAs) are widely distributed across the human body and play varied roles in regulating cellular processes. In recent years, they have gained the attention of the scientific community as key regulators of cancer due to their diverse functional roles and complex regulatory mechanisms. Aberrant expression of lncRNAs contributes to tumor progression, functioning as oncogenes that modulate various pathways through different mechanisms. Early technologies could not study lncRNAs effectively and considered it as "junk" RNA. Studies using gene-expression analyses, functional experiments, and animal-based models have shown that dysregulated lncRNAs are implicated in the maintenance of cancer stem cells (CSCs) and in driving therapeutic resistance. Additionally, lncRNAs have shown promise as valuable biomarkers for cancer diagnosis, prognosis, predicting patient outcomes, and guiding treatment strategies. Moreover, therapeutic strategies targeting lncRNAs, such as antisense oligonucleotides (ASOs), RNA interference (RNAi), exosome-based delivery systems, nanomedicine, virus-mediated therapy, and CRISPR-Cas technologies, have opened new avenues for cancer treatment. This review highlights the diverse roles of lncRNAs in therapeutic resistance and emphasizes their clinical potential as diagnostic and prognostic tools and emerging therapeutic strategies.