LINC00839 knockdown restrains the metastatic behavior of nasopharyngeal carcinoma by sponging miR-454-3p

MiR-454-3p regulates high glucose-induced mesothelial-mesenchymal transition and glycolysis in peritoneal mesothelial cells by targeting STAT3

BACKGROUND

The quality of life of patients receiving long-term peritoneal dialysis (PD) is significantly impacted by the onset of peritoneal fibrosis (PF), and one of the pathological changes is mesothelial-mesenchymal transition (MMT). In this study, we investigated the potential roles of miR-454-3p and signal transducer and activator of transcription 3 (STAT3) in the progression of peritoneal MMT and the underlying mechanisms.

METHODS

Peritoneums were collected to detect morphology via hematoxylin-eosin staining and differentially expressed miRNAs were detected via RT-qPCR. PD effluent-derived cell populations in the peritoneal cavity were isolated from the effluents of 20 PD patients to determine miR-454-3p, STAT3, and MMT markers via Western blotting and RT-qPCR. The relationship between miR-454-3p and STAT3 was examined via a dual-luciferase reporter assay. Western blotting and RT-qPCR were utilized to evaluate the expression of STAT3, MMT markers, and glycolytic enzymes. Immunofluorescence staining revealed the localization and expression of MMT markers and STAT3.

RESULTS

MiR-454-3p was downregulated in the peritoneums and PD effluent-derived cell populations of long-term PD patients. High glucose (HG) treatment promoted HMrSV5 cell MMT and glycolysis. MiR-454-3p overexpression alleviated HG-induced MMT and suppressed the expression of STAT3 and glycolytic enzymes. In contrast, the miR-454-3p inhibitor exacerbated HG-induced MMT and promoted the expression of glycolytic enzymes and STAT3. Moreover, STAT3 was the target of miR-454-3p.

CONCLUSIONS

This study demonstrated the protective role of miR-454-3p in HG-induced MMT and glycolysis in HMrSv5 cells, suggesting that miR-454-3p may prevent MMT by suppressing glycolytic enzymes via the STAT3/PFKFB3 pathway in the HG environment.

LINC00839 in Human Disorders: Insights into its Regulatory Roles and Clinical Impact, with a Special Focus on Cancer

LINC00839 has captured significant attention within a spectrum of human disorders, including acute lung injury, osteoarthritis, and childhood obesity. Notably, aberrant expression patterns of LINC00839 have been observed across diverse cancer tissues and cell lines. LINC00839 emerges as an oncogenic factor in tumorigenesis and exerts a positive influence on tumor-associated behaviors. Its therapeutic potential for various cancers is underscored by its modulatory impact on pivotal signaling pathways, such as PI3K/AKT, OXPHOS, and Wnt/β-catenin. Additionally, LINC00839's role in reducing sensitivity to drug and radiotherapy interventions presents opportunities for targeted intervention. Furthermore, elevated LINC00839 expression indicates advanced clinicopathological features and foretells unfavorable prognoses, as validated by publications and comprehensive analyses of tumor types using TCGA datasets. This review elucidates the multiple regulatory mechanisms and functional implications of LINC00839 in various diseases, especially malignancies, emphasizing its potential as a predictive biomarker and therapeutic target across multiple disease domains in humans.

LINC01376 promotes nasopharyngeal carcinoma tumorigenesis by competitively binding to the SP1/miR-4757/IGF1 axis

The long non-coding RNA (lncRNA)-microRNA (miRNA) interaction network plays a crucial part in the pathogenesis of nasopharyngeal carcinoma (NPC). Here, we discovered a relationship between LINC01376 and miR-4757 in NPC tumor development. First, LINC01376 was abnormally overexpressed in NPC tissues and cells, and its elevated expression was associated with advanced clinical stage and shorter distant metastasis-free survival time. Moreover, biological experiments showed that LINC01376 facilitated the proliferative, invasive, and migratory abilities of NPC cells in vitro and in vivo. Mechanistically, bioinformatics and RT-qPCR assays revealed that LINC01376 knockdown upregulated the expression level of downstream miR-4757, including miR-4757 primary transcript (pri-miR-4757) and mature miR-4757. Furthermore, LINC01376 competitively sponged the transcription factor SP1 and reduced its enrichment in the upstream promoter region of miR-4757 to repress miR-4757 expression. Finally, insulin-like growth factor 1(IGF1) was identified as the target of miR-4757. Rescue experiments indicated that LINC01376 accelerated NPC cell proliferation, migration, and invasion through the miR-4757-5p/IGF1 axis. In conclusion, the SP1/miR-4757/IGF1 axis, which is regulated by LINC01376 in NPC deterioration and metastasis, is expected to provide new insights into the molecular mechanism of NPC carcinogenesis.

LINC00839 promotes malignancy of liver cancer via binding FMNL2 under hypoxia

Liver cancer is one of the most common malignant tumors in the world and metastasis is the leading cause of death associated with liver cancer. Hypoxia is a common feature of solid tumors and enhances malignant character of cancer cells. However, the exact mechanisms involved in hypoxia-driven liver cancer progression and metastasis have not been well clarified so far. The aim of this study was to investigate the contribution of long non-coding RNA (lncRNA) in hypoxia promoting liver cancer progression. We screened and revealed LINC00839 as a novel hypoxia-responsive lncRNA in liver cancer. LINC00839 expression was up-regulated in liver cancer tissues and cell lines, and the patients with high LINC00839 expression had shortened overall survival. LINC00839 further overexpressed under hypoxia and promoted liver cancer cell proliferation, migration, and invasion. Mechanistically, LINC00839 bound multiple proteins that were primarily associated with the metabolism and RNA transport, and positively regulated the expression of Formin-like protein 2 (FMNL2). LINC00839 could promote hypoxia-mediated liver cancer progression, suggesting it may be a clinically valuable biomarker and serve as a molecular target for the diagnosis, prognosis, and therapy of liver cancer.

LINC00839 Promotes Neuroblastoma Progression by Sponging miR-454-3p to Up-Regulate NEUROD1

Neuroblastoma (NB) is the most common extracranial solid malignancy in children. Increasing long non-coding RNAs (lncRNAs) are reported to be associated with NB tumorigenesis and aggressiveness. Here, we attempted to investigate the biological functions of LINC00839 in NB progression as well as its possible pathogenic mechanisms. Public microarray datasets were applied to unearth the abnormally expressed lncRNAs in NB. RT-qPCR analysis was used to measure the expression of LINC00839, miR-454-3p, and neuronal differentiation 1 (NEUROD1) mRNA. The protein level was determined by a western blot assay. CCK-8, plate clone formation, EdU, wound-healing scratch, and transwell assays were employed to evaluate cell proliferation, migration, and invasion. Xenografts were developed in nude mice to determine the effects of LINC00839 on NB tumor growth. Dual-luciferase reporter and RNA immunoprecipitation (RIP) experiments were performed to identify the interaction between miR-454-3p and LINC00839 or NEUROD1. According to GSE datasets (GSE16237 and GSE16476), LINC00839 was found as a potential driver of NB progression. LINC00839 expression was higher in NB tumor tissues and cells. Also, LINC00839 expression was positively correlated with MYCN amplification, advanced INSS stages, and worse prognosis. Silencing of LINC00839 suppressed cell proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) in vitro. Mechanistically, LINC00839 could act as a sponge of miR-454-3p to facilitate the expression of its target NEUROD1. Moreover, miR-454-3p was demonstrated to exert an anti-cancer activity in NB. More importantly, the tumor-suppressive properties mediated by LINC00839 knockdown were significantly counteracted by the inhibition of miR-454-3p or overexpression of NEUROD1. Our study demonstrates that LINC00839 exerts an oncogenic role in NB through sponging miR-454-3p to up-regulate NEUROD1 expression, deepening our comprehension of lncRNA involved in NB and providing access to the possibility of LINC00839 as a therapeutic target for NB.