Knockdown of LINC00657 inhibits the viability, migration and invasion of pancreatic cancer cells by regulating the miR-520h/CKS1B axis

Long non-coding RNA Linc00657 up-regulates Skp2 to promote the progression of cervical cancer through lipid reprogramming and regulation of immune microenvironment

More and more evidence shows that long non-coding RNA (lncRNA) plays an important role in the biological behavior of many kinds of malignant tumors, but the specific function of lncRNA Linc00657 in cervical cancer is still unknown. The purpose of this study is to explore the effect of Linc00657 on the malignant progression of cervical cancer and its potential mechanism. In two kinds of cervical cancer cell lines and normal cervical epithelial cells, qRT-PCR showed increased expression of Linc00657 in cervical cancer cells. Through MTT, clone formation test, flow cytometry, wound healing test and Transwell test, it has been found that overexpression of Linc00657 could promote the proliferation,migration and invasion of cervical cancer cells，and inhibit apoptosis. Through the StarBase database, it was found that there may be a mutual regulatory relationship between Linc00657 and Skp2, and Skp2 may be the downstream target of Linc00657. QRT-PCR detection confirmed that the expression of Skp2 was increased in cervical cancer cells with overexpression of Linc00657. TIMER2 database found that Skp2 was associated with lipid metabolic enzymes and immune cell infiltration. It was found that Linc00657 knockdown inhibited tumor growth and metastasis and inhibited the expression of Skp2 in vivo. In short, our research shows that Linc00657 has carcinogenic properties in cervical cancer, and LINC00657 promotes the occurrence of cervical cancer by up-regulating the expression of Skp2. We predict that Linc00657/mir30s/Skp2 axis plays a role in the malignant progression of cervical cancer. In addition, Skp2 may participate in cancer immune response and promote lymph node metastasis of cervical cancer through lipid reprogramming. These findings also provide promising targets for the diagnosis and treatment of cervical cancer.

CircSEMA6A upregulates PRRG4 by targeting MiR-520h and recruiting ELAVL1 to affect cell invasion and migration in papillary thyroid carcinoma

Objective

As the most prevalent type of thyroid malignancy, papillary thyroid carcinoma (PTC) accounts for over 80% of all thyroid cancers. Circular RNAs (circRNAs) have been found to regulate multiple cancers, including PTC.

Materials and methods

Quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting were used to analyse RNA and protein levels. Fluorescence in situ hybridization (FISH) was used to detect the distribution of the target genes. Functional experiments and animal experiments were implemented to analyse the biological functions of target genes in vitro and in vivo. Luciferase reporter, RNA pulldown, RNA binding protein immunoprecipitation (RIP) and mRNA stability assays were used to probe the underlying mechanisms.

Results

CircSEMA6Awas found to be upregulated in PTC tissues and cells, and its circular structure was verified. CircSEMA6A promotes PTC cell migration and invasion. Moreover, circSEMA6A functions as a competing endogenous RNA (ceRNA) to upregulate proline rich and Gla domain 4 (PRRG4) expression by sponging microRNA-520h (miR-520h). CircSEMA6A recruits ELAV1 to stabilize PRRG4 mRNA and drives PTC progression via PRRG4.

Conclusion

CircSEMA6A upregulates PRRG4 by targeting miR-520h and recruiting ELAVL1 to affect the invasion and migration of PTC cells, offering insight into the molecular mechanisms of PTC.

CKS1B as a potential target for prognostic assessment and intervention in pancreatic cancer and its role in abnormal proliferation and cellular phenotype through mediation of cell cycle signaling pathways

OBJECTIVES

To investigate the role of cell cycle protein-dependent kinase regulatory subunit 1B (CKS1B) in driving the aggressive and rapid proliferation observed in pancreatic cancer.

METHODS

A comprehensive analysis was carried out using raw mRNA information and data from 2 databases: the cancer genome atlas and gene expression omnibus. The differential expression of CKS1B at the mRNA and tissue levels in cancer and adjacent paracancerous tissues were assessed. Additionally, the relationship of CKS1B expression and overall survival (OS) rate was investigated using Kaplan-Meier survival curves. Potential molecular mechanisms by which CKS1B may influence the biological characteristics of pancreatic cancer were explored using resources available within the encyclopedia of RNA interactomes database.

RESULTS

The CKS1B exhibited significant differential expression at the mRNA as well as protein levels. A correlation with statistical significance between CKS1B expression and N stage, age, and alcohol consumption was observed. Notably, high CKS1B expression was determined as a predictive factor for worse OS. Furthermore, the analysis revealed a potential synergistic role between CKS1B and the molecule PKMYT1, which could impact the ATR-Chk1-Cdc25 signaling pathway and disrupt the G2/M checkpoint within the cell cycle, ultimately promoting abnormal tumor proliferation.

CONCLUSION

The CKS1B may serve as a novel potential prognostic factor in pancreatic cancer and is involved in the abnormal proliferation biology phenotype by mediating cell cycle signaling pathways.

Linc00657 promoted pyroptosis in THP-1-derived macrophages and exacerbated atherosclerosis via the miR-106b-5p/TXNIP/NLRP3 axis

Long intergenic non-coding RNA 00657 (linc00657) is involved in various diseases, whereas its role in atherosclerosis (AS) development remains inconclusive. This study was designed to investigate the effects and underlying mechanisms of linc00657 in atherogenesis. The results showed that ox-LDL treatment significantly induced pyroptosis in human THP-1-derived macrophages. The secretion levels of LDH and pro-inflammatory factors were markedly enhanced, and the integrity of plasma membranes was disrupted in ox-LDL-treated THP-1-derived macrophages. These effects were significantly compensated after transfection with linc00657 siRNA and became more evident by linc00657 overexpression. Moreover, the effects of linc00657 overexpression on pyroptosis of THP-1-derived macrophages can also be robustly reversed by TXNIP knockdown or miR-106b-5p mimics transfection. Mechanistically, linc00657 enhanced TXNIP expression by competitively binding to miR-106b-5p, promoting NLRP3 inflammasome activation. Finally, we found that linc00657 overexpression significantly increased the expression of pyroptosis-related factors and decreased miR-106b-5p level in the aorta of high-fat-diet-fed apoE-/- mice. Furthermore, linc00657 up-regulation enlarged the plaque area, exacerbated plasma lipid profile, and increased pro-inflammatory cytokines levels in the serum, effects that were reversed by injection of miR-106b-5p agomir. This evidence indicated that linc00657 stimulated macrophage pyroptosis and aggravated the progression of AS via the miR-106b-5p/TXNIP/NLRP3 pathway.

m6A Modification Mediates Exosomal LINC00657 to Trigger Breast Cancer Progression Via Inducing Macrophage M2 Polarization

BACKGROUND

Exosome-mediated transfer of long noncoding RNAs (lncRNAs) is critical for the cell-cell crosstalk in the tumor microenvironment. Nevertheless, the role of breast cancer (BC) cell-derived exosomal lncRNA in macrophage polarization during the development of BC remains unclear.

METHODS

The key lncRNAs carried by BC cell-derived exosomes were identified by RNA-seq. CCK-8, flow cytometry, and transwell assay were conducted to analyze the role of LINC00657 in BC cells. In addition, immunofluorescence, qRT-PCR, western blot, and MeRIP-PCR were used to evaluate the function and underlying mechanism of exosomal LINC00657 in macrophage polarization.

RESULTS

LINC00657 was distinctly upregulated in BC-derived exosomes and it was associated with increased m6A methylation modification levels. In addition, the depletion of LINC00657 significantly diminished the proliferative activity, migration and invasion potential of BC cells, and it also accelerated cell apoptosis. Exosomal LINC00657 from MDA-MB-231 cells could facilitate macrophage M2 activation, thus stimulating BC development in turn. Furthermore, LINC00657 activated the TGF-β signaling pathway by sequestering miR-92b-3p in macrophages.

CONCLUSION

Exosomal LINC00657 secreted by BC cells could induce macrophage M2 activation, and these macrophages preferentially contributed to the malignant phenotype of BC cells. These results improve our understanding of BC and suggest a new therapeutic strategy for patients with BC.

Nitroxoline suppresses metastasis in bladder cancer via EGR1/circNDRG1/miR-520h/smad7/EMT signaling pathway

Bladder cancer is one of the most common and deadly cancer worldwide. Current chemotherapy has shown limited efficacy in improving outcomes for patients. Nitroxoline, an old and widely used oral antibiotic, which was known to treat for urinary tract infection for decades. Recent studies suggested that nitroxoline suppressed the tumor progression and metastasis, especially in bladder cancer. However, the underlying mechanism for anti-tumor activity of nitroxoline remains unclear.

Methods: CircRNA microarray was used to explore the nitroxoline-mediated circRNA expression profile of bladder cancer lines. Transwell and wound-healing assay were applied to evaluate the capacity of metastasis. ChIP assay was chosen to prove the binding of promotor and transcription factor. RNA-pulldown assay was performed to explore the sponge of circRNA and microRNA.

Results: We first identified the circNDRG1 (has_circ_0085656) as a novel candidate circRNA. Transwell and wound-healing assay demonstrated that circNDRG1 inhibited the metastasis of bladder cancer. ChIP assay showed that circNDRG1 was regulated by the transcription factor EGR1 by binding the promotor of host gene NDRG1. RNA-pulldown assay proved that circNDRG1 sponged miR-520h leading to the overexpression of smad7, which was a negative regulatory protein of EMT.

Conclusions: Our research revealed that nitroxoline may suppress metastasis in bladder cancer via EGR1/circNDRG1/miR-520h/smad7/EMT signaling pathway.

Long Noncoding RNA 00472: A Novel Biomarker in Human Diseases

Long non-coding RNAs (lncRNAs) play important roles in human diseases. They control gene expression levels and influence various biological processes through multiple mechanisms. Functional abnormalities in lncRNAs are strongly associated with occurrence and development of various diseases. LINC00472, which is located on chromosome 6q13, is involved in several human diseases, particularly cancers of the breast, lung, liver, osteosarcoma, bladder, colorectal, ovarian, pancreatic and stomach. Importantly, LINC00472 can be used as a biomarker for breast cancer cell sensitivity to chemotherapeutic regimens, including doxorubicin. LINC00472 is regulated by microRNAs and several signaling pathways. However, the significance of LINC00472 in human diseases has not been clearly established. In this review, we elucidate on the significance of LINC00472 in various human diseases, indicating that LINC00472 may be a diagnostic, prognostic as well as therapeutic target for these diseases.