LINC00665 Targets miR-214-3p/MAPK1 Axis to Accelerate Hepatocellular Carcinoma Growth and Warburg Effect

lncRNA POLR2J4 Plays a Biomarker Role in Hepatitis B Virus-Related Hepatocellular Carcinoma Through Regulating miR-214-3p

Identifying novel therapeutic targets for hepatitis B virus (HBV)-induced hepatocellular carcinoma (HCC) has become a key goal in liver cancer research. Even though long non-coding RNAs (lncRNAs) do not code proteins, they could regulate the expression of functional genes and thus mediate disease development. The aim of this study was to estimate the role of lncRNA POLR2J4 (POLR2J4) in the progression of hepatitis B virus-related hepatocellular carcinoma (HBV-HCC) to pinpoint a potential biomarker. This study included 109 patients diagnosed with HBV-positive HCC, from whom tissue samples were collected. The expression level of POLR2J4 was evaluated by qPCR. The significance of POLR2J4 in HBV-HCC development and prognosis was estimated by Chi-square, Kaplan-Meier, and Cox analysis. In vitro, POLR2J4 was regulated in HBV-HCC cells, and its effect on cell growth and metastasis was assessed by CCK8 and Transwell assay. The interaction between POLR2J4 and miR-214-3p was evaluated through the luciferase reporter and RNA immunoprecipitation assays. In tumor tissues of HBV-HCC patients, there was an observed increase in the expression of POLR2J4. The increase was closely related with patients' presence of cirrhosis and vascular invasion, higher AFP, and advanced Edmondson grade and TNM stage. An upregulation of POLR2J4 predicted a poor prognosis for HBV-HCC patients and served as an independent indicator. In HBV-related HCC cells, silencing POLR2J4 suppressed cell proliferation, migration, and invasion. Furthermore, POLR2J4 negatively regulated miR-214-3p reversing the inhibition of cellular processes. POLR2J4 acted as a prognostic biomarker and a tumor promoter of HBV-HCC by modulating miR-214-3p.

LINC00665 promotes glycolysis in lung adenocarcinoma cells via the let-7c-5p/HMMR axis

Lung adenocarcinoma (LUAD) is one of the most lethal and common malignancies. The energy metabolism of LUAD is a critical factor affecting its malignant progression, and research on this topic can aid in the development of novel cancer treatment targets. Bioinformatics analysis of the expression of long non-coding RNA (lncRNA) LINC00665 in LUAD was performed. Downstream regulatory molecules of LINC00665 were predicted using the StarBase database. We used quantitative reverse transcription polymerase chain reaction and western blot to measure the expression at mRNA and protein levels, respectively. The effects of the LINC00665/let-7c-5p/HMMR axis on cell viability in vitro were tested by CCK-8 assay. The regulatory effects on glycolysis were analyzed by extracellular acidification rate, oxygen consumption rate, glucose uptake, adenosine triphosphate production, and lactate production. The predicted competitive endogenous RNA mechanism between LINC00665 and let-7c-5p/HMMR was verified by a dual-luciferase reporter gene assay. LINC00665 was upregulated in LUAD. Silencing LINC00665 inhibited tumor proliferation and reduced the glycolytic activity of tumor cells. Additionally, the expression of LINC00665 had a negative correlation with that of let-7c-5p, while the expression of HMMR was remarkably inhibited by let-7c-5p. HMMR could affect the development of LUAD by influencing glycolytic capacity. Mechanistically, LINC00665 acted as a molecular sponge to absorb let-7c-5p and targeted HMMR. Transfection of let-7c-5p inhibitor or overexpression of HMMR plasmid could reverse the inhibition in proliferation and glycolysis of LUAD cells induced by silencing of LINC00665. In summary, this study demonstrated that the LINC00665/let-7c-5p/HMMR regulatory axis promoted the tumorigenesis of LUAD by enhancing aerobic glycolysis, suggesting that this regulatory axis was an effective target for inhibiting LUAD progression and providing theoretical support for the development of new drugs for LUAD.

MiR-214-3p overexpression-triggered chondroitin polymerizing factor (CHPF) inhibition modulates the ferroptosis and metabolism in colon cancer

Colon cancer is a common cancer with high mortality globally. The role of chondroitin polymerizing factor (CHPF) has been elucidated in various cancers. However, its role and mechanism remain unknown in colon cancer. CHPF expression was examined by GEPIA database, reverse transcription-quantitative polymerase chain reaction and western blot. The relationship between CHPF expression and the clinicopathologic characteristics as well as miR-214-3p level was determined in colon cancer patients. The role and mechanism of CHPF in the growth, ferroptosis, and glycolysis of colon cancer cells were evaluated by cell counting kit-8, biochemical detections, luciferase, and western blot experiments. Additionally, the role of CHPF was explored in xenografted mice. CHPF expression was increased and was related to advanced TNM stage, poor differentiation and shorter overall survival in patients with colon cancer. Knockdown of CHPF inhibited colon cancer cell growth, and downregulated the expression of proteins involving in ferroptosis and glycolysis both in vitro and in vivo. Besides, CHPF silencing increased the levels of ferrous iron and ROS, but decreased glucose uptake, lactate product, and ATP level in vitro. Mechanically, miR-214-3p directly targeted CHPF and negatively regulated its expression. Upregulation of miR-214-3p reduced cell viability, glucose uptake, lactate product, and ATP level, but increased the levels of ferrous iron and ROS, which were reversed by the overexpression of CHPF. Upregulation of CHPF predicted poor prognosis, and miR-214-3p/CHPF axis inhibited growth, downregulated the levels of glycolysis-related indexes, and promoted ferroptosis in colon cancer cells.

The novel circRNA circ_0045881 inhibits cell proliferation and invasion by targeting mir-214-3p in triple-negative breast cancer

BACKGROUND

Triple-negative breast cancer (TNBC) is the most lethal subtype of breast cancer (BC). The circRNA-miRNA‒mRNA axis is a promising biomarker for the early diagnosis and prognosis of BC. However, the critical circRNA mediators involved in TNBC progression and the underlying regulatory mechanism involved remain largely unclear.

METHODS

In this study, we carried out a circRNA microarray analysis of 6 TNBC patients and performed a gene ontology (GO) analysis. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis was used to characterize important circRNAs involved in TNBC progression. The interaction between circRNAs and miRNAs was determined by dual luciferase and RNA immunoprecipitation (RIP) assays. Moreover, Transwell, wound healing and Cell Counting Kit-8 (CCK8) assays were performed with altered circRNA or miRNA expression in MDA-MB-231 and BT-549 cells to investigate the roles of these genes in cell invasion, migration and proliferation.

RESULTS

A total of 78 circRNAs were differentially expressed in TNBC tissues, and the hsa_circ_0045881 level was significantly decreased in TNBC tissues and cells. Lentivirus-mediated hsa_circ_0045881 overexpression in MDA-MB-231 and BT-549 cells significantly reduced cell invasion and migration capacity. Additionally, hsa_circ_0045881 interacted with miR-214-3p in MDA-MB-231 cells. miR-214-3p mimics in MDA-MB-231 and BT-549 cells significantly enhanced cell invasion, migration and proliferation, but the other combinations of inhibitors had opposite effects on cell activity.

CONCLUSIONS

Our data indicated that the circRNA has_circ_0045881 plays key roles in TNBC progression and that hsa_circ_0045881 might act as a sponge for miR-214-3p to modulate its levels in TNBC cells, thereby regulating cell invasion, metastasis and proliferation. hsa_circ_004588 might be a potential prognostic marker and therapeutic target for TNBC.

LINC00665: A Promising Biomarker in Gastrointestinal Tumors

An increasing volume of studies has reported that long non-codingRNAs (lncRNAs) are involved in the carcinogenesis of many different cancers. Especially in gastrointestinal tumors, lncRNAs are found to participate in various physiological and pathological processes. LncRNAs can regulate gene expression at multiple levels, including transcriptional, post-transcription, translational, and post-translational levels. Long intergenic non-protein coding RNA 665(LINC00665), a novel cancer-related lncRNA, is frequently dysregulated in multiple gastrointestinal tumors, including gastric and colorectal cancers, hepatocellular carcinoma, and so on. In this review, we analyzed the expression and prognostic value of LINC00665 in human gastrointestinal tumors, systematically summarized the current literature about the clinical significance of this lncRNA, and explored the regulatory mechanisms of LINC00665 as a competing endogenous RNA (ceRNA) in tumor progression. Consequently, we concluded that LINC00665 might act as a prognostic biomarker and a potential target for gastrointestinal tumor diagnosis and treatment.

Endoplasmic Reticulum Stress and Metabolism in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer, accounting for 85% to 90% of all liver cancer cases. It is a hepatocyte-derived primary tumor, causing 550,000 deaths per year, ranking it as one of the most common cancers worldwide. The liver is a highly metabolic organ with multiple functions, including digestion, detoxification, breakdown of fats, and production of bile and cholesterol, in addition to storage of vitamins, glycogen, and minerals, and synthesizing plasma proteins and clotting factors. Due to these fundamental and diverse functions, the malignant transformation of hepatic cells can have a severe impact on the liver's metabolism. Furthermore, tumorigenesis is often accompanied by activation of the endoplasmic reticulum (ER) stress pathways, which are known to be highly intertwined with several metabolic pathways. Because HCC is characterized by changes in the metabolome and by an aberrant activation of the ER stress pathways, the aim of this review was to summarize the current knowledge that links ER stress and metabolism in HCC, thereby focusing on potential therapeutic targets.

Sequence pre-training-based graph neural network for predicting lncRNA-miRNA associations

MicroRNAs (miRNAs) silence genes by binding to messenger RNAs, whereas long non-coding RNAs (lncRNAs) act as competitive endogenous RNAs (ceRNAs) that can relieve miRNA silencing effects and upregulate target gene expression. The ceRNA association between lncRNAs and miRNAs has been a research hotspot due to its medical importance, but it is challenging to verify experimentally. In this paper, we propose a novel deep learning scheme, i.e. sequence pre-training-based graph neural network (SPGNN), that combines pre-training and fine-tuning stages to predict lncRNA-miRNA associations from RNA sequences and the existing interactions represented as a graph. First, we utilize a sequence-to-vector technique to generate pre-trained embeddings based on the sequences of all RNAs during the pre-training stage. In the fine-tuning stage, we use Graph Neural Network to learn node representations from the heterogeneous graph constructed using lncRNA-miRNA association information. We evaluate our proposed scheme SPGNN on our newly collected animal lncRNA-miRNA association dataset and demonstrate that combining the $k$-mer technique and Doc2vec model for pre-training with the Simple Graph Convolution Network for fine-tuning is effective in predicting lncRNA-miRNA associations. Our approach outperforms state-of-the-art baselines across various evaluation metrics. We also conduct an ablation study and hyperparameter analysis to verify the effectiveness of each component and parameter of our scheme. The complete code and dataset are available on GitHub: https://github.com/zixwang/SPGNN.

Prognostic and clinicopathological values of LINC00665 in cancers: a systematic review and China population-based meta-analysis

BACKGROUND

Recent studies have uncovered that the aberrant expression of LINC00665 contributes to the malignant pathological process of various cancers and is closely related to the unfavorable prognosis of patients with cancer. However, a systematic analysis of the prognostic and clinicopathologic values of LINC00665 in cancers has not been conducted.

OBJECTIVE

We aim to clarify the association of LINC00665 expression with patient survival and clinicopathologic phenotypes in cancers.

METHODS

An electronic search of PubMed, Embase and Web of Science was performed to select eligible literature. Pooled hazard ratio (HR) and odds ratio (OR) were calculated to assess the clinical importance of LINC00665. The fixed-effects model was used to analyze the combined HR values and 95% CI when the studies had no significant heterogeneity (P > 0.1 for the Chi-square test or I2 < 50%). Begg's test and sensitivity analysis were also conducted. This study was registered in The International Prospective Register of Systematic Reviews (PROSPERO registration number: CRD42021290123).

RESULTS

A total of 710 patients from 10 eligible studies were enrolled in this meta-analysis, which was based on China population. The pooled results of this analysis revealed that high-level expression of LINC00665 was notably correlated with poor overall survival (HR = 2.08, 95% CI = 1.57-2.75) and recurrence-free survival (HR = 2.49, 95% CI = 1.63-3.80) in human cancers. Elevated LINC00665 expression was also correlated with more advanced clinical stage, earlier lymph node metastasis, lower tumor differentiation, earlier distant metastasis and larger tumor size.

CONCLUSION

LINC00665 expression was critically related to the cancer prognosis, which has important prognostic implications for clinical prediction.

Exosomal miR-214-3p from senescent osteoblasts accelerates endothelial cell senescence

BACKGROUND

Osteoporosis is a common systemic bone disease that leads to bone fragility and increases the risk of fracture. However, the pathogenesis of osteoporosis is considered to be highly complex. The exosomes can regulate the communication between cells. The specific mechanism of information transmission between osteoblasts and endothelial cells is worthy of further study.

METHODS

Exosomes were isolated and verified from senescent osteoblasts. The source and properties of exosomes were determined by TEM, particle size analysis and western blot. We established the co-culture model of endothelial cells and senescent osteoblasts. We used qRT-PCR to identify differentially expressed miRNAs. The functional changes of vascular endothelial cells were verified by cell transfection. β-Galactosidase cell senescence assay, Hoechst cell apoptosis assay, Ki67 cell proliferation assay and Transwell migration assay were used to verify cell senescence, apoptosis, proliferation, and migration. The potential target gene of miRNA was detected by bio-informatics pathway and double luciferase report.

RESULTS

We discovered that senescent osteoblasts could promote the senescence and apoptosis of vascular endothelial cells and inhibit their proliferation and migration. miR-214-3p was upregulated in senescent osteoblast-derived exosomes. miR-214-3p could effectively promote senescence and apoptosis of endothelial cells and inhibit proliferation and migration ability. L1CAM is a miR-214-3p direct target gene determined by bio-informatics and double luciferase report.

CONCLUSIONS

In conclusion, senescent osteoblast-derived exosomes can accelerate endothelial cell senescence through miR-214-3p/L1CAM pathway. Our experiments reveal the role of exosomes in the skeletal microenvironment.

Serum lncRNA LINC01535 as Biomarker of Diagnosis, Prognosis, and Disease Progression in Breast Cancer

BACKGROUND

Breast cancer has become the world's leading cancer, the leading killer of women's health, with a high mortality rate. With the development of medical technology, lncRNAs are widely used in the diagnosis and prognosis of various tumors, so finding new specific molecular markers and targets is the key to prolonging the survival time of breast cancer patients.

MATERIALS AND METHODS

The expressions of lncRNA LINC01535 and miR-214-3p in breast cancer were detected by quantitative real-time PCR (qRT-PCR). The diagnostic significance of LINC01535 in breast cancer was assessed by ROC curve. The prognostic value of LINC01535 was verified by Kaplan-Meier method. The regulation of low expression of LINC01535 on proliferation and other biological abilities of breast cancer cells was determined by CCK-8 and Transwell method. The luciferase activity report assays indicated the relationship between LINC01535 and miR-214-3p.

RESULTS

LINC01535 was elevated in breast cancer, which was negatively correlated with miR-214-3p, and miR-214-3p expression was decreased. LINC01535 proved to be promising in the diagnosis and prognosis of breast cancer. Low expression of LINC01535 targeting miR-214-3p had regulatory significance on tumor progression, lymph node metastasis and TNM stage.

CONCLUSION

Silencing LINC01535 inhibited the proliferation capacity, migration level and invasion of breast cancer cells in vitro. LINC01535 was likely to be the focus of continued attention as a diagnostic and prognosis marker for breast cancer in the future.

A Concise Review on Dysregulation of LINC00665 in Cancers

Long Intergenic Non-Protein Coding RNA 665 (LINC00665) is an RNA gene located on the minus strand of chromosome 19. This lncRNA acts as a competing endogenous RNA for miR-4458, miR-379-5p, miR-551b-5p, miR-3619-5p, miR-424-5p, miR-9-5p, miR-214-3p, miR-126-5p, miR-149-3p, miR-379-5p, miR-665, miR-34a-5p, miR-186-5p, miR-138-5p, miR-181c-5p, miR-98, miR-195-5p, miR-224-5p, miR-3619, miR-708, miR-101, miR-1224-5p, miR-34a-5p, and miR-142-5p. Via influencing expression of these miRNAs, it can enhance expression of a number of oncogenes. Moreover, LINC00665 can influence activity of Wnt/β-Catenin, TGF-β, MAPK1, NF-κB, ERK, and PI3K/AKT signaling. Function of this lncRNA has been assessed through gain-of-function tests and/or loss-of-function studies. Furthermore, diverse research groups have evaluated its expression levels in tissue samples using microarray and RT-qPCR techniques. In this manuscript, we have summarized the results of these studies and categorized them in three sections, i.e., cell line studies, animal studies, and investigations in clinical samples.

Seven Hub Genes Predict the Prognosis of Hepatocellular Carcinoma and the Corresponding Competitive Endogenous RNA Network

Purpose

This study was aimed at identifying hub genes and ceRNA regulatory networks linked to prognosis in hepatocellular carcinoma (HCC) and to identify possible therapeutic targets.

Methods

Differential expression analyses were performed to detect the differentially expressed genes (DEGs) in the four datasets (GSE76427, GSE6764, GSE62232, and TCGA). The intersected DEmRNAs were identified to explore biological significance by enrichment analysis. We built a competitive endogenous RNA (ceRNA) network of lncRNA-miRNA-mRNA. The mRNAs of the ceRNA network were used to perform Cox and Kaplan-Meier analyses to obtain prognosis-related genes, followed by the selection of genes with an area under the curve >0.8 to generate the random survival forest model and obtain feature genes. Furthermore, the feature genes were subjected to least absolute shrinkage and selection operator (LASSO) and univariate Cox analyses were used to identify the hub genes. Finally, the infiltration status of immune cells in the HCC samples was determined.

Results

A total of 1923 intersected DEmRNAs were identified in four datasets and involved in cell cycle and carbon metabolism. ceRNA network was created using 10 lncRNAs, 67 miRNAs, and 1,923 mRNAs. LASSO regression model was performed to identify seven hub genes, SOCS2, MYOM2, FTCD, ADAMTSL2, TMEM106C, LARS, and KPNA2. Among them, TMEM106C, LARS, and KPNA2 had a poor prognosis. KPNA2 was considered a key gene base on LASSO and Cox analyses and involved in the ceRNA network. T helper 2 cells and T helper cells showed a higher degree of infiltration in HCC.

Conclusion

The findings revealed seven hub genes implicated in HCC prognosis and immune infiltration. A corresponding ceRNA network may help reveal their potential regulatory mechanism.

MicroRNAs as Potential Tools for Predicting Cancer Patients’ Susceptibility to SARS-CoV-2 Infection and Vaccination Response

Coronavirus disease (COVID-19) is an infectious disease that is caused by a highly contagious and severe acute respiratory syndrome—coronavirus 2 (SARS-CoV-2). This infection started to spread across the world in 2019 and rapidly turned into a global pandemic, causing an urgent necessity for treatment strategies development. The mRNA vaccines against SARS-CoV-2 can trigger an immune response, providing genetic information that allows the production of spike glycoproteins. MiRNAs play a crucial role in diverse key cellular processes, including antiviral defense. Several miRNAs are described as key factors in SARS-CoV-2 human infection through the regulation of ACE2 levels and by the inhibition of SARS-CoV-2 replication and spike expression. Consequently, these molecules have been considered as highly promising biomarkers. In numerous human malignancies, it has been recognized that miRNAs expression is dysregulated. Since miRNAs can target SARS-CoV-2-associated mRNAs, in cancer patients, the deregulation of these molecules can impair the immune response to the vaccines. Therefore, in this review, we propose a miRNA profile of seven SARS-CoV-2-related miRNAs, namely miR-214, miR-98-5p, miR-7-5p, miR-24-3p, miR-145-5p, miR-223-3p and miR-15b-5p, that are deregulated in a high number of cancers and have the potential to be used as prognostic biomarkers to stratify cancer patients.

Combined identification of three lncRNAs in serum as effective diagnostic and prognostic biomarkers for hepatitis B virus-related hepatocellular carcinoma

Hepatitis B virus-related hepatocellular carcinoma (HBV-related HCC) is a common, highly invasive malignant tumor associated with a high mortality rate. This study aimed to identify the effective diagnostic and prognostic biomarkers for HBV-related HCC. With HBV-related HCC RNA-sequencing data of The Cancer Genome Atlas (TCGA) database, 159 differentially expressed long non-coding RNAs (lncRNAs) between HBV-related HCC and para-carcinoma normal samples were identified, and 12 lncRNAs were eventually assessed for deeper research. Classification analysis developed a three-lncRNA signature of AC005332.5, ELF3-AS1, and LINC00665, which was demonstrated to be the most discriminatory with an AUC (Area Under the Curve) value of 0.913 (95% CI: 0.8610-0.9665) and verified in validation patients. The expression levels of AC005332.5, ELF3-AS1, and LINC00665 were significantly changed with different tumor stages or grades. Survival analysis revealed that AC005332.5, ELF3-AS1, and LINC00665 were highly associated with the prognosis of overall survival. Additionally, the lncRNA signature yielded statistical significance to predict clinical outcomes independently from other clinical variables in validation patients, as suggested in the multivariate Cox hazards analysis. Conclusively, a three-lncRNA signature of AC005332.5, ELF3-AS1, and LINC00665 may serve as an excellent diagnostic biomarker for HBV-related HCC and potential prognostic significance for HBV-related HCC sufferers. This article is protected by copyright. All rights reserved.

Exploring the underlying molecular mechanism of liver cancer cells under hypoxia based on RNA sequencing

Background

The aim of our study was to use the differentially expressed mRNAs (DEmRNAs) and differentially expressed miRNAs (DEmiRNAs) to illustrate the underlying mechanism of hypoxia in liver cancer.

Methods

In this study, a cell model of hypoxia was established, and autophagy activity was measured with western blotting and transmission electron microscopy. The effect of hypoxia conditions on the invasion of liver cancer cell was evaluated. RNA sequencing was used to identify DEmRNAs and DEmiRNAs to explore the mechanism of hypoxia in liver cancer cells.

Results

We found that autophagy activation was triggered by hypoxia stress and hypoxia might promote liver cancer cell invasion. In addition, a total of 407 shared DEmRNAs and 57 shared DEmiRNAs were identified in both HCCLM3 hypoxia group and SMMC-7721 hypoxia group compared with control group. Furthermore, 278 DEmRNAs and 24 DEmiRNAs were identified as cancer hypoxia-specific DEmRNAs and DEmiRNAs. Finally, we obtained 19 DEmiRNAs with high degree based on the DEmiRNA-DEmRNA interaction network. Among them, hsa-miR-483-5p, hsa-miR-4739, hsa-miR-214-3p and hsa-miR-296-5p may be potential gene signatures related to liver cancer hypoxia.

Conclusions

Our study may help to understand the potential molecular mechanism of hypoxia in liver cancer.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12863-022-01055-9.

The Emerging Roles of LINC00665 in Human Cancers

Long non-coding RNAs (lncRNAs) are non-coding RNAs that have more than 200 nucleotides and can participate in the regulation of gene expression in various ways. An increasing number of studies have shown that the dysregulated expression of lncRNAs is related to the occurrence and progression of human cancers. LINC00665 is a novel lncRNA, which is abnormally expressed in various human cancers, such as lung cancer, breast cancer, prostate cancer, and glioma. LINC00665 functions in many biological processes of tumor cells, such as cell proliferation, migration, invasion, angiogenesis, and metabolism, and is related to the clinicopathological characteristics of cancer patients. LINC00665 can play biological functions as a ceRNA, directly binding and interacting with proteins, and as an upstream molecule regulating multiple signaling pathways. In this review, we comprehensively summarize the expression level, function, and molecular mechanisms of LINC00665 in different human cancers and emphasize that LINC00665 is a promising new diagnostic, prognostic biomarker, and therapeutic target.