Long noncoding RNA NORAD acts as a ceRNA mediates gemcitabine resistance in bladder cancer by sponging miR-155-5p to regulate WEE1 expression

FENDRR represses Bladder Cancer Cell Proliferation, Stemness, Migration, Invasion, and EMT Process by Targeting miR-18a-5p/AFF4 Axis

Bladder cancer (BC) is the most prevalent malignancy of the urinary tract and ranks among the most common tumors globally due to its high recurrence and fatality rates. Evidence suggests that long noncoding RNAs (lncRNAs) may serve as novel biomarkers for cancer therapy. The study aimed to investigate the functions of lncRNA fetal-lethal non-coding developmental regulatory RNA (FENDRR) in regulating malignant phenotypes of BC cell lines (T24 and RT-4) and the underlying mechanism. RT-qPCR was used to measure FENDRR, miR-18a-5p, and AF4/FMR2 family member 4 (AFF4) expression in BC tissue samples and cell lines. Subcellular fractionation assay and fluorescence in situ hybridization were conducted to determine the localization of FENDRR in T24 and RT-4 cell. EdU, sphere formation, Transwell invasion, and wound healing assays were carried out to detect the changes in BC cell proliferation, stemness, invasion, and migration in response to FENDRR or AFF4 dysregulation. Protein levels of epithelial-mesenchymal transition (EMT) markers were quantified by western blotting. The interaction between miR-18a-5p and FENDRR (or AFF4) was verified by luciferase reporter assays. Experimental results revealed that FENDRR expression was downregulated in BC tissue samples and cell lines, with primary localization in cytoplasm of T24 and RT-4 cells. FENDRR overexpression inhibited BC cell proliferation, migration, invasion, stemness, and EMT process. FENDRR was shown to bind with miR-18a-5p, and AFF4 is a direct target of miR-18a-5p. In addition, AFF4 knockdown partially counteracted the effect of FENDRR on malignant phenotypes of BC cells. In summary, FENDRR represses BC cell proliferation, migration, invasion, stemness, and EMT process by targeting the miR-18a-5p/AFF4 axis.

lncRNAs: New players of cancer drug resistance via targeting ABC transporters

Cancer drug resistance poses a significant obstacle to successful chemotherapy, primarily driven by the activity of ATP-binding cassette (ABC) transporters, which actively efflux chemotherapeutic agents from cancer cells, reducing their intracellular concentrations and therapeutic efficacy. Recent studies have highlighted the pivotal role of long noncoding RNAs (lncRNAs) in regulating this resistance, positioning them as crucial modulators of ABC transporter function. lncRNAs, once considered transcriptional noise, are now recognized for their complex regulatory capabilities at various cellular levels, including chromatin modification, transcription, and post-transcriptional processing. This review synthesizes current research demonstrating how lncRNAs influence cancer drug resistance by modulating the expression and activity of ABC transporters. lncRNAs can act as molecular sponges, sequestering microRNAs that would otherwise downregulate ABC transporter genes. Additionally, they can alter the epigenetic landscape of these genes, affecting their transcriptional activity. Mechanistic insights reveal that lncRNAs contribute to the activity of ABC transporters, thereby altering the efflux of chemotherapeutic drugs and promoting drug resistance. Understanding these interactions provides a new perspective on the molecular basis of chemoresistance, emphasizing the regulatory network of lncRNAs and ABC transporters. This knowledge not only deepens our understanding of the biological mechanisms underlying drug resistance but also suggests novel therapeutic strategies. In conclusion, the intricate interplay between lncRNAs and ABC transporters is crucial for developing innovative solutions to combat cancer drug resistance, underscoring the importance of continued research in this field.

P-glycoprotein (P-gp)-driven cancer drug resistance: biological profile, non-coding RNAs, drugs and nanomodulators

Drug resistance has compromised the efficacy of chemotherapy. The dysregulation of drug transporters including P-glycoprotein (P-gp) can mediate drug resistance through drug efflux. In this review, we highlight the role of P-gp in cancer drug resistance and the related molecular pathways, including phosphoinositide 3-kinase (PI3K)-Akt, phosphatase and tensin homolog (PTEN) and nuclear factor-κB (NF-κB), along with non-coding RNAs (ncRNAs). Extracellular vesicles secreted by the cells can transport ncRNAs and other proteins to change P-gp activity in cancer drug resistance. P-gp requires ATP to function, and the induction of mitochondrial dysfunction or inhibition of glutamine metabolism can impair P-gp function, thus increasing chemosensitivity. Phytochemicals, small molecules and nanoparticles have been introduced as P-gp inhibitors to increase drug sensitivity in human cancers.

The role of miR-155 in urologic malignancies

MicroRNAs (miRNAs) are a class of short non-coding RNAs that play a crucial role in regulating gene expression across multiple levels. They are involved in a wide range of physiological processes, including proliferation, differentiation, apoptosis, and cell cycle control. In recent years, miRNAs have emerged as pivotal regulatory molecules in the development and progression of tumors. Among these, miR-155 has garnered significant attention due to its high expression in various diseases, particularly urologic malignancies. Since an extensive corpus of studies having focused on the roles of miR-155 in various urologic malignancies, it is essential to summarize the current evidence on this topic through a comprehensive review. Altered miR-155 expression is related to various physiological and pathological processes, including immune response, inflammation, tumor development and treatment resistance. Notably, alterations in miR-155 expression have been observed in urologic malignancies as well. The up-regulation of miR-155 expression is commonly observed in urologic malignancies, contributing to their progression by targeting specific proteins and signaling pathways. This article provides a comprehensive review of the significant role played by miR-155 in the development of urologic malignancies. Furthermore, the potential of miR-155 as a biomarker and therapeutic target in urologic malignancies is also discussed.

NORAD-Regulated Signaling Pathways in Breast Cancer Progression

Long non-coding RNA activated by DNA damage (NORAD) has recently been associated with pathologic mechanisms underlying cancer progression. Due to NORAD's extended range of interacting partners, there has been contradictory data on its oncogenic or tumor suppressor roles in BC. This review will summarize the function of NORAD in different BC subtypes and how NORAD impacts crucial signaling pathways in this pathology. Through the preferential binding to pumilio (PUM) proteins PUM1 and PUM2, NORAD has been shown to be involved in the control of cell cycle, angiogenesis, mitosis, DNA replication and transcription and protein translation. More recently, NORAD has been associated with PUM-independent roles, accomplished by interacting with other ncRNAs, mRNAs and proteins. The intricate network of NORAD-mediated signaling pathways may provide insights into the potential design of novel unexplored strategies to overcome chemotherapy resistance in BC treatment.

Construction and identification of lncRNA/circRNA-coregulated ceRNA networks in gemcitabine-resistant bladder carcinoma

OBJECTIVES

To explore the regulatory networks that underlie the development of chemoresistance in bladder cancer.

METHODS

We analyzed profiles of differentially expressed long non-coding RNAs (lncRNAs), circular RNAs (circRNAs), microRNAs (miRNAs) and messenger RNA (mRNAs) in gemcitabine-resistant/sensitive bladder cancer cells using next-generation sequencing data.

RESULTS

Hundreds of differentially expressed lncRNAs and miRNAs and thousands of circRNAs and mRNAs were identified. Bioinformatics analysis revealed the chromosomal localizations, classification and coexpression of mRNAs, as well as candidates for cis and trans regulation by lncRNAs. Furthermore, Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis of differentially expressed mRNAs and circRNAs indicated important functional roles of coregulated RNAs, thus establishing competing endogenous RNA (ceRNA) and protein-protein interactions networks that may underlie chemoresistance in bladder cancer. We demonstrated that lncRNA LINP1 can act as a ceRNA by inhibiting miR-193a-5p to increase TP73 expression; and that lncRNA ESRG and hsa_circ_0075881 can simultaneously bind miR-324-3p to increase ST6GAL1 expression. Modulation of ceRNA network components using ablation and overexpression approaches contributed to gemcitabine resistance in bladder cancer cells.

CONCLUSIONS

These results elucidate mechanisms by which lncRNAs and circRNAs coregulate the development of bladder cancer cell resistance to gemcitabine, thus laying the foundation for future research to identify biomarkers and disease targets.

Roles of non-coding RNAs in the metabolism and pathogenesis of bladder cancer

Bladder cancer (BC) is featured as the second most common malignancy of the urinary tract worldwide with few treatments leading to high incidence and mortality. It stayed a virtually intractable disease, and efforts to identify innovative and effective therapies are urgently needed. At present, more and more evidence shows the importance of non-coding RNA (ncRNA) for disease-related study, diagnosis, and treatment of diverse types of malignancies. Recent evidence suggests that dysregulated functions of ncRNAs are closely associated with the pathogenesis of numerous cancers including BC. The detailed mechanisms underlying the dysregulated role of ncRNAs in cancer progression are still not fully understood. This review mainly summarizes recent findings on regulatory mechanisms of the ncRNAs, long non-coding RNAs, microRNAs, and circular RNAs, in cancer progression or suppression and focuses on the predictive values of ncRNAs-related signatures in BC clinical outcomes. A deeper understanding of the ncRNA interactive network could be compelling framework for developing biomarker-guided clinical trials.

Diagnostic value of Long non-coding Ribonucleic Acid non-coding activated by Deoxyribonucleic Acid damage in pulmonary tuberculosis and its regulatory role in Mycobacterium tuberculosis infection of macrophages

Pulmonary tuberculosis (PTB) infection is a chronic inflammatory response caused by Mycobacterium tuberculosis (Mtb). The purpose of this study was to confirm the value of Long non-coding RNA (LncRNA) non-coding activated by DNA damage (NORAD) in the diagnosis of PTB and to explore its mechanism in Mtb-infected macrophages. NORAD serum levels were estimated by qRT-PCR in 90 PTB patients and 85 healthy individuals. ROC curves were employed to assess the diagnostic value of NORAD for PTB. Human and murine macrophages were infected with Mtb strain H37Rv. CCK-8 and ELISA detected macrophages viability and inflammatory cytokine secretion. A dual-luciferase reporter assay was performed to analyze the targeting relationship between NORAD and microRNA (miR)-618. NORAD was significantly elevated in patients with PTB, and its positivity was correlated with inflammatory cytokines IL-1 β (r = 0.854), TNF-α (r = 0.617), IL-6 (r = 0.585). With an AUC of 0.918, and sensitivity and specificity of 80.0% and 89.4%, respectively, NORAD remarkedly identified PTB patients from healthy individuals. Furthermore, Mtb infection significantly increased NORAD levels in THP-1 and RAW264.7 and increased their viability and inflammation (P <0.001). However, this increased effect was weakened by reduced NORAD. Dual-luciferase reporter assay confirmed that miR-618 in macrophages was a target miRNA for NORAD and can be negatively regulated by it. Moreover, elevated miR-618 suppressed macrophage viability and inflammation in Mtb infection. NORAD is a potential diagnostic biomarker for PTB and is involved in Mtb infected macrophage activity and inflammation by targeting miR-618. This article is protected by copyright. All rights reserved.