A comprehensive review of web-based non-coding RNA resources for cancer research

Ellagic acid inhibits human colon cancer HCT-116 cells by regulating long noncoding RNAs

The natural phenolic compound ellagic acid exerts anti-cancer effects, including activity against colorectal cancer (CRC). Previously, we reported that ellagic acid can inhibit the proliferation of CRC, and can induce cell cycle arrest and apoptosis. This study investigated ellagic acid-mediated anticancer effects using the human colon cancer HCT-116 cell line. After 72 h of ellagic acid treatment, a total of 206 long noncoding RNAs (lncRNAs) with differential expression greater than 1.5-fold were identified (115 down-regulated and 91 up-regulated). Furthermore, the co-expression network analysis of differentially expressed lncRNA and mRNA showed that differential expressed lncRNA might be the target of ellagic acid activity in inhibiting CRC.

MIR31HG polymorphisms are related to steroid-induced osteonecrosis of femoral head among Chinese Han population

Backgrounds

MIR31 host gene (MIR31HG) polymorphisms play important roles in the occurrence of osteonecrosis. However, the association of MIR31HG polymorphisms with the risk of steroid-induced osteonecrosis of the femoral head (SONFH) remains unclear. In this study, we aimed to investigate the correlation between MIR31HG polymorphisms and SONFH susceptibility in the Chinese Han population.

Methods

A total of 708 volunteers were recruited to detect the effect of seven single nucleotide polymorphisms (SNPs) in the MIR31HG gene on SONFH risk in the Chinese Han population. Genotyping of MIR31HG polymorphisms was performed using the Agena MassARRAY platform. The odds ratio (OR) and 95% confidence interval (95% CI) were used to evaluate the correlation between MIR31HG polymorphisms and SONFH risk using logistic regression model.

Results

According to the results of genetic model, rs10965059 in MIR31HG was significantly correlated with the susceptibility to SONFH (OR = 0.56, p = 0.002). Interestingly, the stratified analysis showed that rs10965059 was associated with the reduced risk of SONFH in subjects aged > 40 years (OR = 0.30, p < 0.001) and male populations (OR = 0.35, p < 0 .001). Moreover, rs10965059 was associated with the reduced risk of bilateral SONFH (OR = 0.50, p = 0.002). Finally, multi-factor dimension reduction (MDR) results showed that the combination of rs1332184, rs72703442, rs2025327, rs55683539, rs2181559, rs10965059 and rs10965064 was the best model for predicting SONFH occurrence (p < 0.0001).

Conclusion

The study indicated that rs10965059 could be involved in SONFH occurrence in the Chinese Han population, which might provide clues for investigating the role of MIR31HG in the pathogenesis of SONFH.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-022-05785-w.

LINC00518 Promotes Cell Malignant Behaviors via Influencing EIF4A3-Mediated mRNA Stability of MITF in Melanoma

Melanoma has become the most severe sort of skin cancer, deriving from the pigment-producing melanocytes. Existing research has validated that long noncoding RNAs (lncRNAs) have critical function in the progression of cancers. LINC00518 has been studied in cutaneous melanoma; however, the molecular mechanism of LINC00518 in melanoma needs in-depth investigation. In our study, LINC00518 was revealed to be upregulated in melanoma tissues and cells, and melanoma patients in high LINC00518 expression group had poorer prognosis as depicted in GEPIA database. Functional assays revealed that LINC00518 depletion inhibited cell proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT). Furthermore, MITF was confirmed to be upregulated in melanoma tissues and cells, and melanoma patients in high MITF expression group had poorer prognosis as displayed in GEPIA database. MITF expression was positively connected to LINC00518 expression. Additionally, results of mechanism assays uncovered EIF4A3 could bind with LINC00518 and MITF, and LINC00518 recruited EIF4A3 to stabilize MITF mRNA. Finally, it was demonstrated that upregulation of MITF could partially abrogate the inhibitory impact of LINC00518 knockdown on melanoma cell malignant behaviors. To summarize, LINC00518 promotes the malignant processes of melanoma cells through targeting EIF4A3/MITF axis, which might provide novel potential biomarkers for melanoma prognosis.

Noncoding RNAs in triple negative breast cancer: Mechanisms for chemoresistance

Triple-negative breast cancer (TNBC) is the most aggressive subtype among breast cancers with high recurrence and this condition is partly due to chemoresistance. Therefore, fully understanding the mechanism of TNBC-resistance is the key to overcoming chemoresistance, which will be an effective strategy for TNBC therapy. Various potential mechanisms involved in the chemoresistance of TNBC have been investigated and indicated that noncoding RNAs (ncRNAs) especially microRNAs (miRNAs), long noncoding RNAs (lncRNAs) and circular RNAs (circRNAs) take part in most TNBC resistance. The ncRNA-induced chemoresistance process is involved in the alteration of many activities. here, we mainly summarize the mechanisms of ncRNAs in the chemoresistance of TNBC and discuss the potential clinical application of ncRNAs in the treatment of TNBC, indicating that targeting ncRNAs might be a promising strategy for resensitization to chemotherapies.

miRNA-6715-5p Inhibits Cellular Proliferation and Invasion in Colorectal Cancer by Directly Targeting CST4

Background

Data on the correlation between CST4 and colorectal cancer (CRC) metastasis are scarce. The aim of this study was to analyze CST4 expression and investigate its biological roles and related microRNA- (miRNA-) mediated regulation in CRC.

Methods

The expression of CST4 was examined in cancer tissues and their corresponding adjacent normal tissues from 40 gastric adenocarcinoma patients. The expression level of CST4 in specimens (cancer and normal tissues) was assessed through immunohistochemistry and/or quantitative polymerase chain reaction. miRNAs targeting CST4 in CRC were predicted by bioinformatics software. CST4 was knocked down in HCT116 cells and candidate miRNAs were transfected into HCT116 cells, and the effects of CST4 knockdown and miRNA transfection on cell proliferation and invasion were examined using CCK8, cell colony formation, and Transwell migration assays. Luciferase double-reporter assays were performed to verify the relationship between miRNA and CST4.

Results

The expression of CST4 in CRC tissues was significantly higher than that in normal paracancerous tissues, but the results for miRNA-6715-5p were opposite. Regardless of CST4 knockdown or miRNA-6715-5p overexpression, the proliferation and invasion ability of HCT116 cells decreased significantly. Luciferase double-reporter assays showed that the upregulation of miR-6715-5p significantly reduced the luciferase activities of the CST4 3'-UTR plasmid in HCT116 cells.

Conclusion

CST4 may be involved in CRC proliferation and metastasis. miRNA-6715-5p directly targets CST4 and negatively regulates its expression.

MiR-182 Promotes Ischemia/Reperfusion-Induced Acute Kidney Injury in Rat by Targeting FoxO3

BACKGROUND

Renal ischemia/reperfusion (I/R) injury (RIRI) is the main cause of acute kidney injury (AKI) in patients. We investigated the role of miR-182 after renal ischemia/reperfusion (I/R) in rat to characterize the microRNA (miRNA) network activated during development and recovery from RIRI.

METHODS AND RESULTS

12 h after lethal (45 min) renal ischemia, AKI was verified by renal histology (tubular necrosis and regeneration), blood urea nitrogen level, and renal mRNA expression in Wistar rats. We found that miR-182 markedly increased after renal I/R. In cell hypoxia/reoxygenation model, we found similar upregulation of miR-182. In function gain/loss assay, we confirmed an impaired effect of miR-182 and identified Forkhead box O3 (FoxO3) as a direct downstream target of it. By using miR-182 antagomir, the I/R injury was markedly ameliorated.

CONCLUSIONS

Our results demonstrate that miR-182 promotes cell apoptosis and I/R injury through directly binding to FoxO3. The present study will provide potential therapeutic targets for renal I/R-induced AKI, and open a new avenue for AKI treatment by manipulating miRNAs levels.

Atezolizumab and blockade of LncRNA PVT1 attenuate cisplatin resistant ovarian cancer cells progression synergistically via JAK2/STAT3/PD-L1 pathway

OBJECTIVE

To investigate the relationship between lncRNA PVT1(PVT1) level and PD-L1 expression and their functions in cisplatin resistant epithelial ovarian cancer (CREOC).

METHODS

PVT1 and PD-L1 in ovarian cancer tissues were detected and analyzed. The cells proliferation, apoptosis, invasion abilities and potential mechanism were detected by cell functional experiments and western-blot assay, respectively.

RESULTS

The average expressions of PVT1 and PD-L1 in CREOC tissues were significantly higher. The expression of PVT1 is positively associated with PD-L1 in CREOC. Higher expressions of PVT1 and PD-L1 indicated more malignant clinical behavior and shorter PFS and OS. Knockdown of PVT1 inhibited the proliferation and invasion and promote apoptosis for A2780cis cells, which may be related to decrease the expression of PD-L1 via repressing JAK2/STAT3 pathway.

CONCLUSIONS

The synergistic therapeutic strategy using LncRNA PVT1-targeted therapy and immune checkpoint blockade of PD-L1 warrant study further for ovarian cancer patients with cisplatin resistant recurrence.

The Biogenesis and Functions of circRNAs and Their Roles in Breast Cancer

Recent statistics show that breast cancer is among the most frequent cancers in clinical practice. It is also the second-leading cause of cancer-related deaths among women worldwide. CircRNAs are a new class of endogenous regulatory RNA molecules whose 5’ end and 3’ end are connected together to form a covalently closed single-stranded loop by back-splicing. CircRNAs present the advantages of disease-specific expression and excellent expression stability, and they can modulate gene expression at posttranscriptional and transcriptional levels. CircRNAs are abnormally expressed in multiple cancers, such as breast cancer, and drive the initiation and progression of cancer. In this review, we describe current knowledge about the functions of circRNAs and generalize their roles in various aspects of breast cancer, including cell proliferation, cell cycle, apoptosis, invasion and metastasis, autophagy, angiogenesis, drug resistance, and tumor immunity, and their prognostic and diagnostic value. This may add to a better understanding of the functions and roles of circRNAs in breast cancer, which may become new diagnostic and predictive biomarkers of breast cancer.

TUG1 promotes retinoblastoma progression by sponging miR-516b-5p to upregulate H6PD expression

Background

Retinoblastoma (RB), depicted as an aggressive eye cancer, mainly occurs in infancy and childhood and is followed by high mortality and poor prognosis. Increasing evidence has revealed that long noncoding RNA taurine upregulated gene 1 (TUG1) is closely linked to the progression of diverse cancers. Nonetheless, the specific function and molecular regulatory mechanism of TUG1 in RB still need to be explored.

Methods

To explore the specific role of TUG1 in RB. TUG1 expression was detected by real-time quantitative polymerase chain reaction (RT-qPCR). Cell counting kit-8 (CCK-8), colony formation, 5-ethynyl-2’-deoxyuridine (EdU), caspase-3, terminal-deoxynucleotidyl transferase mediated nick end labeling (TUNEL) and western blot assays were utilized to study the role of TUG1 in RB. The binding relation between miR-516b-5p and TUG1 or hexose-6-phosphate dehydrogenase/glucose 1-dehydrogenase (H6PD) was analyzed by luciferase reporter and RNA immunoprecipitation (RIP) assays.

Results

The expression of TUG1 was upregulated in RB cells. TUG1 knockdown repressed proliferation ability and promoted apoptosis ability of RB cells. Moreover, TUG1 could bind with miR-516b-5p, which targeted H6PD in RB. In addition, the expression of H6PD was negatively and positively regulated by miR-516b-5p and TUG1 in RB, respectively. Finally, H6PD overexpression could partially offset the effects of TUG1 deficiency on cell proliferation and apoptosis.

Conclusions

TUG1 promoted the development of RB by sponging miR-516b-5p to upregulate H6PD expression, which might provide a new thought for researching RB-related molecular mechanism.

Genes and pathways involved in senescence bypass identified by functional genetic screens

Cellular senescence is a state of stable and irreversible cell cycle arrest with active metabolism, that normal cells undergo after a finite number of divisions (Hayflick limit). Senescence can be triggered by intrinsic and/or extrinsic stimuli including telomere shortening at the end of a cell's lifespan (telomere-initiated senescence) and in response to oxidative, genotoxic or oncogenic stresses (stress-induced premature senescence). Several effector mechanisms have been proposed to explain senescence programmes in diploid cells, including the induction of DNA damage responses, a senescence-associated secretory phenotype and epigenetic changes. Senescent cells display senescence-associated-β-galactosidase activity and undergo chromatin remodeling resulting in heterochromatinisation. Senescence is established by the pRb and p53 tumour suppressor networks. Senescence has been detected in in vitro cellular settings and in premalignant, but not malignant lesions in mice and humans expressing mutant oncogenes. Despite oncogene-induced senescence, which is believed to be a cancer initiating barrier and other tumour suppressive mechanisms, benign cancers may still develop into malignancies by bypassing senescence. Here, we summarise the functional genetic screens that have identified genes, uncovered pathways and characterised mechanisms involved in senescence evasion. These include cell cycle regulators and tumour suppressor pathways, DNA damage response pathways, epigenetic regulators, SASP components and noncoding RNAs.

lncRNA CCAT1/miR-490-3p/MAPK1/c-Myc positive feedback loop drives progression of acute myeloid leukaemia

Acute myeloid leukaemia (AML) is a frequently diagnosed malignancy in adults. Long non-coding RNA (lncRNA) colon cancer-associated transcript 1 (CCAT1) has been well known to play vital roles in multiple malignancies including AML. Unfortunately, the detailed mechanism of CCAT1 in AML progression remains obscure. In this study, we demonstrated that CCAT1 was up-regulated in AML samples while its target, miR-490-3p, was relatively down-regulated. CCAT1 markedly increased viability and metastasis of AML cells, while miR-490-3p had opposite effects. CCAT1 could specifically bind to miR-490-3p and reduce its expression and activity, and MAPK1 was a target gene of miR-490-3p. Overexpressed CCAT1 could induce MAPK1 expression and c-Myc reciprocally increased CCAT1 expression. Our data implied that miR-490-3p could be a novel therapeutic target for AML, and highlights the crucial role of CCAT1/miR-490-3p/MAPK1/c-Myc positive feedback loop in AML progression.

Role of extracellular vesicles in tumour microenvironment

In recent years, it has been demonstrated that extracellular vesicles (EVs) can be released by almost all cell types, and detected in most body fluids. In the tumour microenvironment (TME), EVs serve as a transport medium for lipids, proteins, and nucleic acids. EVs participate in various steps involved in the development and progression of malignant tumours by initiating or suppressing various signalling pathways in recipient cells. Although tumour-derived EVs (T-EVs) are known for orchestrating tumour progression via systemic pathways, EVs from non-malignant cells (nmEVs) also contribute substantially to malignant tumour development. Tumour cells and non-malignant cells typically communicate with each other, both determining the progress of the disease. In this review, we summarise the features of both T-EVs and nmEVs, tumour progression, metastasis, and EV-mediated chemoresistance in the TME. The physiological and pathological effects involved include but are not limited to angiogenesis, epithelial-mesenchymal transition (EMT), extracellular matrix (ECM) remodelling, and immune escape. We discuss potential future directions of the clinical application of EVs, including diagnosis (as non-invasive biomarkers via liquid biopsy) and therapeutic treatment. This may include disrupting EV biogenesis and function, thus utilising the features of EVs to repurpose them as a therapeutic tool in immunotherapy and drug delivery systems. We also discuss the overall findings of current studies, identify some outstanding issues requiring resolution, and propose some potential directions for future research. Video abstract.

ELK1/lncRNA-SNHG7/miR-2682-5p feedback loop enhances bladder cancer cell growth

AIMS

The purpose of this paper is to unearth the ceRNA regulatory mechanism of SNHG7 in bladder cancer (BCa).

MATERIALS AND METHODS

The expression of SNHG7 in BCa cells was uncovered by qRT-PCR. The biological functions of SNHG7 in BCa cells were explored by CCK-8 assay, colony formation assay, flow cytometry analysis, wound healing assay and transwell assay. Luciferase reporter assay and RIP assay were applied to analyze the interaction of ELK1 with SNHG7 or miR-2682-5p.

KEY FINDINGS

SNHG7 was conspicuously highly expressed in BCa tissues and cells. The upregulated expression of SNHG7 was related with poor prognosis in BCa patients. Moreover, SNHG7 exerted oncogenic functions in BCa through enhancing cell growth, migration and invasion. ELK1 increased the level of SNHG7 by binding with the promoter region of SNHG7. SNHG7 strengthened the expression of ELK1 via acting as a sponge of miR-2682-5p. Both ELK1 and miR-2682-5p involved in the SNHG7-mediated BCa progression.

SIGNIFICANCE

ELK1/SNHG7/miR-2682-5p feedback loop enhances cell growth, migration and invasion in BCa.

FtMt promotes glioma tumorigenesis and angiogenesis via lncRNA SNHG1/miR-9-5p axis

OBJECTIVE

This study is to investigate the effects and the mechanisms of mitochondrial ferritin (FtMt) on the glioma tumorigenesis and angiogenesis.

METHODS

FtMt expression was detected in glioma tissues and cells as well as in nude mouse tissues. Cell proliferation and apoptosis rate were observed following transfection of LV-FtMt or sh-FtMt in glioma cell line. Moreover, glioma cells with FtMt over-expression/knockdown were co-cultured with human umbilical vein endothelial cells (HUVECs) to observe its function on HUVEC proliferation, angiogenic ability and the vascular endothelial growth factor (VEGF) content. Gain and loss of function of small nucleolar RNA host gene 1 (SNHG1) and miR-9-5p were performed in glioma cells and GBM nude mice to observe its effect on glioma cell proliferation and HUVEC angiogenic ability. Luciferase reporter gene and RIP assay were employed to inspect the interactions among SNHG1, FtMt and miR-9-5p. Additionally, a xenograft mouse model was applied to determine the role of FtMt in glioma.

RESULTS

In this work, FtMt was strongly expressed in glioma tissues and cells as well as in nude mouse tumor tissues. The employment of the loss-of and gain-of functions assays illustrated that FtMt enhanced glioma tumorigenesis and angiogenesis. Mechanistically, our findings showed that FtMt positively related to SNHG1 while negatively correlated with miR-9-5p, and both SNHG1 and FtMt can competitively bind with miR-9-5p. Besides, the inhibition effects of sh-FtMt on glioma were surveyed in vivo experiments.

CONCLUSION

Evidence in this study suggested that FtMt promotes glioma tumorigenesis and angiogenesis via SNHG1 mediated miR-9-5p expression, which may provide a theoretical basis for glioma treatment.

Pharmacoepigenetics and Pharmacoepigenomics: An Overview

BACKGROUND

The rapid and major advances being made in epigenetics are impacting pharmacology, giving rise to new sub-disciplines in pharmacology, pharmacoepigenetics, the study of the epigenetic basis of variation in response to drugs; and pharmacoepigenomics, the application of pharmacoepigenetics on a genome-wide scale.

METHODS

This article highlights the following aspects of pharmacoepigenetics and pharmacoepigenomics: epigenetic therapy, the role of epigenetics in pharmacokinetics, the relevance of epigenetics to adverse drug reactions, personalized medicine, drug addiction, and drug resistance, and the use of epigenetic biomarkers in drug therapy.

RESULTS

Epigenetics is having an increasing impact on several areas of pharmacology.

CONCLUSION

Pharmacoepigenetics and pharmacoepigenomics are new sub-disciplines in pharmacology and are likely to have an increasing impact on the use of drugs in clinical practice.

LINC02418 promotes malignant behaviors in lung adenocarcinoma cells by sponging miR-4677-3p to upregulate KNL1 expression

Background

Lung adenocarcinoma (LAD) is a prevalent type of bronchogenic malignant tumor and one of the most critical factors related to human death. Long noncoding RNAs (lncRNAs) are involved in many complex biological processes and have been emerged as extremely important regulators of various cancers. LINC02418, a novel lncRNA, hasn’t been mentioned in previous studies on cancer development. Therefore, it’s important to define the potential function of LINC02418 in LAD.

Methods

Gene expression was examined by RT-qPCR or western blot. CCK-8, colony formation, TUNEL, and transwell assays were utilized to study the role of LINC02418 in LAD. The interaction of miR-4677-3p with LINC02418 (or KNL1) was verified through luciferase reporter, RIP and RNA pull-down assays.

Results

High expression of LINC02418 was observed in LAD specimens and cells. Downregulation of LINC02418 obstructed the proliferation and motility of LAD cells. Moreover, LINC02418 negatively modulated miR-4677-3p expression and miR-4677-3p overexpression could repress cell proliferation and migration. Moreover, kinetochore scaffold 1 (KNL1) expression was negatively modulated by miR-4677-3p but positively regulated by LINC02418. Furthermore, miR-4677-3p could bind with LINC02418 (or KNL1). Finally, KNL1 overexpression reversed the inhibitory function of LINC02418 deficiency in the malignant behaviors of LAD cells.

Conclusions

LINC02418 contributes to the malignancy in LAD via miR-4677-3p/KNL1 signaling, providing a probable therapeutic direction for LAD.

A LHFPL3-AS1/miR-580-3p/STAT3 Feedback Loop Promotes the Malignancy in Melanoma via Activation of JAK2/STAT3 Signaling

Melanoma is one of the severe skin cancers, accounting for three fourths of all deaths caused by skin cancers and gathering attention from researchers. Previous studies have elucidated that long noncoding RNAs (lncRNA) engage actively in tissue physiology and disease development, especially in tumorigenesis. LncRNA LHFPL3 antisense RNA 1 (LHFPL3-AS1) has rarely been mentioned in researches regarding cancers; therefore, the underlying role and function of LHFPL3-AS1 in melanoma arouse our interest. Data from our work suggested that LHFPL3-AS1 expression was markedly elevated in melanoma tissues and cells. Of note, patients with melanoma with high level of LHFPL3-AS1 were burdened with unfavorable prognosis. Functionally, it has been revealed that LHFPL3-AS1 exerted pro-growth, pro-invasion, and pro-EMT functions in melanoma. Mechanistically, it was figured out that LHFPL3-AS1 could be transcriptionally activated by STAT3. In turn, LHFPL3-AS1 served as a sponge of miR-580-3p to augment STAT3 expression, resulting in activated JAK2/STAT3 signaling pathway in melanoma. IMPLICATIONS: Our study revealed a novel positive feedback loop LHFPL3-AS1/miR-580-3p/STAT3 in melanoma, which might contribute to finding potential therapeutic targets for melanoma.

Circular RNA_LARP4 Sponges miR-1323 and Hampers Progression of Esophageal Squamous Cell Carcinoma Through Modulating PTEN/PI3K/AKT Pathway

BACKGROUND

Emerged as important regulators in cancer progression, circular RNAs have been tested to participate in diverse biological processes. Former studies have suggested that circular RNA_LARP4 (circLARP4) exerts indispensable function on the development of different cancers such as gastric cancer and ovarian cancer. Nonetheless, the specific role of circLARP4 has not been discovered in ESCC.

AIMS

The aim of this study is to explore the biological function and regulatory mechanism of circLARP4 in ESCC.

METHODS

CircLARP4, miR-1323, and PTEN expression levels were quantified by RT-qPCR. CCK-8, EdU, caspase-3 activity, wound healing, transwell, and western blot assays were chosen to assess ESCC cell growth. Luciferase reporter, RIP, and RNA pull-down assays were performed to examine the interaction between miR-1323 and circLARP4 (or PTEN).

RESULTS

CircLARP4 expression was observably downregulated in ESCC cell lines, and overexpressed circLARP4 restrained cell proliferation and migration whereas boosted cell apoptosis in ESCC. Molecular mechanism experiments revealed that circLARP4 could act as a sponge for miR-1323 and negatively modulated miR-1323 expression in ESCC. Interestingly, the repression of miR-1323 was correlated with inhibitive cell proliferation, migration, and promotive apoptosis. Besides, miR-1323 bound with PTEN, and PTEN expression was negatively regulated by miR-1323 whereas positively regulated by circLARP4 in ESCC. Moreover, rescue assays testified that miR-1323 overexpression or PTEN deficiency could countervail the function of circLARP4 overexpression on ESCC progression. More importantly, circLARP4 played an inhibitory role in PI3K/AKT pathway.

CONCLUSIONS

CircLARP4 sponges miR-1323 and hampers tumorigenesis of ESCC through modulating PTEN/PI3K/AKT pathway.

6-Gingerol protects cardiomyocytes against hypoxia-induced injury by regulating the KCNQ1OT1/miR-340-5p/ PI3K/AKT pathway

BACKGROUND

Hypoxia could induce cardiomyocytes injury and lead to heart disease. Studies have shown that 6-Gingerol has a protective effect on cardiomyocytes injury, but its molecular mechanism is still unclear.

METHODS

Cell counting kit 8 (CCK8) and flow cytometry assays were used to measure the viability and apoptosis of cardiomyocytes. Western blot (WB) analysis was performed to assess the levels of proliferation, apoptosis, and phosphatidylinositol 3- kinase/protein kinase B (PI3K/AKT) signaling pathway-related proteins. The reactive oxygen species (ROS) level, superoxide dismutase (SOD) activity and malondialdehyde (MDA) level were detected by their corresponding Assay Kits. Besides, the expression levels of potassium voltage-gated channel subfamily Q member 1 opposite strand 1 (KCNQ1OT1) and microRNA-340-5p (miR-340-5p) were determined by quantitative real-time polymerase chain reaction (qRT-PCR). Furthermore, dual-luciferase reporter and RNA immunoprecipitation (RIP) assays were used to verify the interaction between KCNQ1OT1 and miR-340-5p.

RESULTS

Hypoxia could inhibit the viability and enhance the apoptosis and oxidative stress of cardiomyocytes to induce cardiomyocytes injury, while 6-Gingerol could alleviate this effect. Overexpression of KCNQ1OT1 aggravated hypoxia-induced cardiomyocytes injury and reversed the protective effect of 6-Gingerol on cardiomyocytes injury. Besides, miR-340-5p could be sponged by KCNQ1OT1, and its overexpression could invert the promotion effect of KCNQ1OT1 overexpression on hypoxia-induced cardiomyocytes injury. Moreover, miR-340-5p expression was regulated by 6-Gingerol and KCNQ1OT1. In addition, hypoxia inactivated the PI3K/AKT signaling pathway, whereas 6-Gingerol and miR-340-5p could reverse this effect.

CONCLUSIONS

6-Gingerol could hinder the expression of KCNQ1OT1 to protect cardiomyocytes from hypoxia-induced injury through regulation of the miR-340-5p/ PI3K/AKT pathway, providing a new mechanism of 6-Gingerol protecting cardiomyocytes from injury.

LncRNA SNHG15 regulates EGFR-TKI acquired resistance in lung adenocarcinoma through sponging miR-451 to upregulate MDR-1

Lung adenocarcinoma (LUAD) is the main component of non-small-cell lung cancer (NSCLC) and causes a great health concern globally. The top priority of LUAD treatment is to deal with gefitinib resistance. Long non-coding RNAs are certified to modify gefitinib resistance in the course of tumor aggravation. The study focuses on addressing the function of small nucleolar RNA host gene 15 (SNHG15) on modifying gefitinib resistance in LUAD. Previously, NOTCH pathway is implicated in LUAD chemo-resistance. SNHG15 level was boosted following the depletion of NOTCH-1 in A549/GR and H1975/GR cells. Functional studies indicated that SNHG15 and multidrug resistance protein 1 (MDR-1) were overexpressed and possess tumor-promoting functions in gefitinib-resistant LUAD cells while miR-451 was downregulated and possess tumor-suppressive behaviors in gefitinib-resistant LUAD cells. Mechanically, the SNHG15 was cytoplasmically distributed in GR LUAD cells. In addition, SNHG15 released MDR-1 from the suppression of miR-451, leading to MDR-1 promotion. In addition, the elevation of SNHG15 could be attributed to ZEB1. Rescue assays highlighted that downstream molecules MDR-1 and miR-451 could reverse the effects of SNHG15 downregulation on gefitinib-resistant LUAD cells. SNHG15 could alter chemo-resistance of LUAD cells to Gefitinib via regulating miR-451/MDR-1, which could be inspiring findings for the advancement of chemo-therapies for LUAD.

TMPO-AS1 promotes cell proliferation of thyroid cancer via sponging miR-498 to modulate TMPO

Background

Thyroid cancer (TC) is the most frequent endocrine malignancy. Long noncoding RNAs (lncRNAs) have been confirmed to act as significant roles in tumor development. The role of lncRNA TMPO-AS1 in TC is still unclear, so it remains to be explored. The aim of the research is to investigate the role and regulatory mechanism of TMPO-AS1 in TC.

Methods

TMPO-AS1 and TMPO expression in TC tumors and cells was detected by TCGA database and QRT-PCR assay respectively. CCK-8, EDU, TUNEL and western blot assays were conducted to identify the biological functions of TMPO-AS1 in TC. Luciferase reporter and RNA pull down assays were conducted to measure the interaction among TMPO-AS1, TMPO and miR-498.

Results

TMPO-AS1 was overexpressed in TC tissues and cell lines. Knockdown of TMPO-AS1 suppressed cell growth and accelerated cell apoptosis in TC. Furthermore, downregulation of TMPO-AS1 suppressed TMPO expression in TC. The data suggested that TMPO expression was upregulated in TC tissues and cell lines and was positively correlated with TMPO-AS1 expression in TC. Furthermore, the expression of miR-498 presented low expression in TC cells. And miR-498 expression was negatively regulated by TMPO-AS1, meanwhile, TMPO expression was negatively regulated by miR-498 in TC cells. Besides, it was confirmed that TMPO-AS1 could bind with miR-498 and TMPO in TC cells. In addition, it was validated that TMPO-AS1 elevated the levels of TMPO via sponging miR-498 in TC cells.

Conclusions

TMPO-AS1 promotes cell proliferation in TC via sponging miR-498 to modulate TMPO.

NCK1-AS1 enhances glioma cell proliferation, radioresistance and chemoresistance via miR-22-3p/IGF1R ceRNA pathway

Glioma is the deadliest disease in human central nerve system. Abnormal expression of long noncoding RNA (lncRNA) expression has been demontrated to be implicated in various cancers. The oncogenic role of lncRNA NCK1-AS1 has been validated in cervical cancer, wheras its role in glioma remians obscure. Our research findings suggested that NCK1-AS1 was upregulated in glioma tissues and cells. NCK1-AS1 deficiency hindered cell proliferation and enhanced cell apoptosis. Additionally, the chemoresistance and radioresistance of glioma cells were impaired by NCK1-AS1 depletion. Moreover, miR-22-3p, a downstream gene of NCK1-AS1, could weaken glioma cell chemoresistance and radioresistance. Similarly, IGF1R was the downstream target gene of miR-22-3p. Further mechanism and function assays demonstrated that NCK1-AS1 promoted glioma cell growth, chemoresistance and radioresistance via sponging miR-22-3p to upregulate IGF1R. Finally, the tumor facilitator function of NCK1-AS1 was also verified by in vivo experiments. Taken together, NCK1-AS1 contributes to glioma cell proliferation, radioresistance and chemoresistance via miR-22-3p/IGF1R ceRNA pathway, which might provide a new insight for improving the radiotherapy and chemotherapy treatments of glioma.

Long noncoding RNA PRKCQ-AS1 promotes CRC cell proliferation and migration via modulating miR-1287-5p/YBX1 axis

Colorectal cancer (CRC) brings more than 600 000 deaths every year around the globe, making itself the third most frequently occurred carcinoma. The great progress human achieved in diagnosis and treatment of various cancers has failed to reverse this trend. Fortunately, growing evidence has implied the relationship between lncRNAs and cancer progression. Long noncoding RNA (lncRNA) PRKCQ-AS1 was heightened in CRC cells and tissues and related with dismal prognosis of CRC patients. Knockdown of PRKCQ-AS1 would induce a decrease in proliferative and migrating ability of CRC cells. Also, PRKCQ-AS1 enriched in cytoplasm of CRC cells and negatively regulated miR-1287-5p level. More important, PRKCQ-AS1 could bind to argonaute 2 and function in the RNA-induced silencing complex with miR-1287-5p. Therefore, PRKCQ-AS1 was a competing endogenous RNA for miR-1287-5p. Subsequently, it was validated that miR-1287-5p could suppress the proliferative and migratory functions in CRC. Furthermore, PRKCQ-AS1 could upregulate the mRNA and protein level of YBX1 targeted by miR-1287-5p. And YBX1 expression was elevated in CRC cells and tissues. Rescue assays in vitro and in vivo showed that overexpression of YBX1 could partly offset the effect of CRC progression induced by knocking down PRKCQ-AS1, demonstrating PRKCQ-AS1 mediating CRC progression via miR-1287-5p/YBX1 pathway.

Comprehensive Transcriptomic Analysis and Experimental Validation Identify lncRNA HOXA-AS2/miR-184/COL6A2 as the Critical ceRNA Regulation Involved in Low-Grade Glioma Recurrence

Purpose

The recurrence and metastasis of glioma are closely related to complex regulatory networks among protein-coding genes, lncRNAs and microRNAs. The aim of this study was to investigate core genes, lncRNAs, miRNAs and critical ceRNA regulatory mechanisms, which are involved in lower-grade glioma (LGG) recurrence.

Materials and Methods

We employed multiple datasets from Chinese Glioma Genome Atlas (CGGA) database and The Cancer Genome Atlas (TCGA) to perform comprehensive transcriptomic analysis. Further in vitro experiments including cell proliferation assay, luciferase reporter assay, and Western blot were performed to validate our results.

Results

Recurrent LGG and glioblastoma (GBM) showed different transcriptome characteristics with less overlap of differentially expressed protein-coding genes (DEPs), lncRNAs (DELs) and miRNAs (DEMs) compared with primary samples. There were no overlapping gene in ontology (GO) terms related to GBM recurrence in the TCGA and CGGA databases, but there were overlaps associated with LGG recurrence. GO analysis and protein–protein interaction (PPI) network analysis identified three core genes: TIMP1, COL1A1 and COL6A2. By hierarchical cluster analysis of them, LGGs could be clustered as Low_risk and High_risk group. The High_risk group with high expression of TIMP1, COL1A1, and COL6A2 showed worse prognosis. By coexpression networks analysis, competing endogenous RNA (ceRNA) network analysis, cell proliferation assay and luciferase reporter assay, we confirmed that lncRNA HOXA-AS2 functioned as a ceRNA for miR-184 to regulate expression of COL6A2, which induced cell proliferation of low-grade glioma.

Conclusion

In this study, we revealed a 3-hub protein-coding gene signature to improve prognostic prediction in LGG, and identified a critical ceRNA regulation involved in LGG recurrence.

LncRNA DDX11-AS1 Promotes Bladder Cancer Occurrence Via Protecting LAMB3 from Downregulation by Sponging miR-2355-5p

Background: As a subtype of human genitourinary system cancer, the morbidity of bladder cancer (BC) continues to rise. Because of the high potentiality of cell metastasis, the 5-year survival rate of BC is relatively low. Long noncoding RNAs (lncRNAs) have been verified by a large body of literature to engage in the tumorigenesis of a few cancers. DDX11-AS1 has been elucidated as a malignancy promoter in several cancers; therefore, its mysterious role in BC attracted our interest as being well worth investigating. Aim of the Study: The primary consideration of this article was to clarify the part that DDX11-AS1 plays in the progression of BC. Methods: The expression of DDX11-AS1 in BC was revealed by quantitative real-time polymerase chain reaction. The biological functions of DDX11-AS1 in BC were evaluated through CCK-8 (Cell Counting Kit-8), EDU, TUNEL (TdT-mediated dUTP nick-end labeling), flow cytometry analysis, and Western Blot assays. Luciferase or RNA immunoprecipitation assay was used to investigate the interaction between miR-2355-5p and DDX11-AS1 (or LAMB3). Results: DDX11-AS1 manifested remarkably high level in BC and promoted the malignancy of BC. Moreover, miR-2355-5p was validated to be able to bind with DDX11-AS1 and inhibit cell proliferation in BC. Furthermore, our data suggested that LAMB3 expression was evidently upregulated in BC cells and inversely modulated by miR-2355-5p. Besides, LAMB3 may bind with miR-2355-5p. Ultimately, rescue assays indicated that the restrained development of BC in sh-DDX11-AS1#1-transfected cells could be restored by enforced expression of LAMB3. Conclusion: DDX11-AS1 facilitates the tumorigenesis of BC by the miR-2355-5p/LAMB3 axis.

FOXM1-induced upregulation of lncRNA OR3A4 promotes the progression of diffuse large B-cell lymphoma via Wnt/β-catenin signaling pathway

Diffuse large B-cell lymphoma (DLBCL) is a leading cause of non-Hodgkin lymphomas. Existing researches have verified that long non-coding RNAs (lncRNAs) play crucial roles in the development of DLBCL, nevertheless, whether lncRNA OR3A4 has influences on the progression of DCBCL needs further exploration. In our study, it was revealed that the expression of OR3A4 was upregulated in DLBCL tumors and cell lines, and patients with high OR3A4 expression suffered from poor prognosis. Knockdown of OR3A4 suppressed cell proliferation and promoted cell apoptosis in DLBCL. Moreover, knockdown of OR3A4 inactivated Wnt/β-catenin signaling pathway, and Riluzole treatment could partially rescue the inhibitive effect of OR3A4 silencing on DLBCL cell proliferation. Furthermore, FOXM1 expression was discovered to be upregulated in DLBCL tissues, and it positively modulated the expression of OR3A4 at transcriptional leve. It was also revealed that FOXM1 knockdown inactivated Wnt/β-catenin signaling pathway. Finally, rescue assays confirmed that OR3A4 overexpression or the treatment of Riluzole could partially countervail the inhibitive effect of FOXM1 silencing on DLBCL progression. Taken together, FOXM1-induced upregulation of OR3A4 enhances the occurrence of DLBCL via Wnt/β-catenin signaling pathway.

SNHG7 Facilitates Hepatocellular Carcinoma Occurrence by Sequestering miR-9-5p to Upregulate CNNM1 Expression

Background: Hepatocellular carcinoma (HCC), the fourth leading cause of cancer-related deaths worldwide, has increased public concern. Data from previous work have validated that long noncoding RNAs are active participators in the malignant processes of a host of cancers. Small nucleolar RNA host gene 7 (SNHG7) has been revealed to act as a tumor promoter in several cancers and SNHG7 inhibition was revealed to suppress cell invasion in HCC. Nevertheless, the specific role of SNHG7 in HCC deserves deeper exploration. Aim of the Study: This work aimed to uncover the role and the regulatory mechanisms of SNHG7 in HCC. Materials and Methods: The expression of SNHG7 and cyclin mediator 1 (CNNM1) in HCC cells were analyzed by quantitative real-time polymerase chain reaction. The influences of SNHG7 on HCC occurrence were studied by cell counting kit-8 (CCK-8), colony formation, flow cytometry analysis, and Western blot assays. Luciferase reporter assay or RNA immunoprecipitation assay was conducted to confirm the relationship between miR-9-5p and SNHG7 (or CNNM1). Results: SNHG7 was overexpressed in HCC tissues and cell lines. SNHG7 facilitated cell proliferation, while suppressed cell apoptosis in HCC. Moreover, miR-9-5p expression was negatively modulated by SNHG7 and therefore was downregulated in HCC cells. We also found that CNNM1 existed in miR-9-5p induced RNA-induced silencing complex and a series of assays verified that CNNM1 acted as the target gene of miR-9-5p. Consequently, the messenger RNA and protein level of CNNM1 were detected to be inversely regulated by miR-9-5p. Moreover, rescue assays demonstrated that CNNM1 overexpression could countervail the SNHG7 depletion-mediated cellular functions of HCC cells. Conclusions: SNHG7 sponges miR-9-5p to upregulate CNNM1 in promoting HCC progression.

Long non-coding RNA LINC01419 mediates miR-519a-3p/PDRG1 axis to promote cell progression in osteosarcoma

Background

Osteosarcoma (OS) is one of the most aggressive malignancies with mortality rate worldwide. Accumulating evidence has revealed that long noncoding RNAs (lncRNAs) exert important functions in regulation of cancer initiation and progression. Recently, long intergenic non-protein coding RNA 1419 (LINC01419) has been reported to function as an oncogene in several cancers. However, its role in OS has not been explored yet.

Methods

qRT-PCR and western blot analyses were implemented to determine the expression of genes. The function of OS cells was assessed through colony formation, EdU, JC-1, TUNEL, transwell, and immunofluorescence (IF) assays. FISH and subcellular fractionation assays were conducted to estimate the localization of LINC01419 in OS cells. The interaction between genes was validated through luciferase reporter and RNA pull down assays.

Results

LINC01419 expression was elevated in OS tissues and cells. Functionally, LINC01419 accelerated OS cell proliferation, motility and EMT. In vivo assay showed that silencing LINC01419 hindered the growth of OS tumors. Mechanistic investigation unveiled that LINC01419 acted as a competing endogenous RNA (ceRNA) to augment PDRG1 expression by miR-519a-3p sequestration. Rescue assays verified the oncogenic effect of LINC01419/miR-519a-3p/PDRG1 axis on OS development.

Conclusion

LINC01419 mediates malignant phenotypes in OS by targeting miR-519a-3p/PDRG1 axis.

Genetic variants of the MIR31HG gene are related to a risk of IgA nephropathy

IgA nephropathy (IgAN) is the most common primary glomerulonephritis worldwide. Previous studies reveal that genetic factors play a crucial role in IgAN progression. This study was conducted to investigate the association between MIR31HG variants and IgAN risk. A total of 836 subjects were recruited to detect the relationship of MIR31HG variants with IgAN susceptibility. Odds ratios (OR) and 95% confidence intervals (CI) were computed to evaluate the associations. Multifactor dimensionality reduction was performed to analyze the SNP-SNP interaction with IgAN risk. Our study showed that rs1332184 and rs55683539 significantly related to an increased risk of IgAN (OR 1.34, p = 0.041; OR 1.39, p = 0.025). Stratified analyses indicated rs72703442, rs55683539, and rs10965064 exhibited strongly enhanced risk of IgAN in age ≤ 35 years (OR 1.55, p = 0.023; OR 1.60, p = 0.012; OR 1.46, p = 0.037). Besides, we found rs1332184, rs55683539 and rs2181559 significantly increased the susceptibility of IgAN in males (OR 1.71, p = 0.003; OR 1.44, p = 0.042; OR 1.60, p = 0.010). We also observed that rs1332184 could enhance IgAN risk for Lee's grade ≥ III (OR 1.39, p = 0.045). Rs55683539 significantly increased a risk of IgAN (OR 1.58, p = 0.027), while rs2025327 had a lower risk of IgAN in Lee's grade < III (OR 0.46, p = 0.007). Interestingly, we found rs72703442 polymorphism was related to hemoglobin (p = 0.043), and rs10965064 was associated with Urine red blood cell (p = 0.040). Our study proposed that MIR31HG polymorphisms associate with susceptibility to IgAN in Chinese population.

LINC00467 enhances head and neck squamous cell carcinoma progression and the epithelial-mesenchymal transition process via miR-299-5p/ubiquitin specific protease-48 axis

BACKGROUND

Head and neck squamous cell carcinoma (HNSCC) has attracted the attention of researchers as a result of its high incidence around the world. This malignancy occurs in the oral cavity, pharynx and larynx in most cases. A number of lncRNAs have been revealed to regulate the malignant neoplasia of several cancers. Nevertheless, the effects of lncRNA LINC00467 in HNSCC have not yet been reported.

METHODS

The expression of LINC00467, miR-299-5p and ubiquitin specific protease-48 (USP48) in HNSCC cells was quantified by a quantitative reverse transcriptase-polymerase chain reaction. The influences of LINC00467 deficiency on HNSCC progression were reflected by cell counting kit-8, colony formation, ethynyl-2-deoxyuridine, wound healing and western blot assays. RIP and luciferase reporter assays were conducted to confirm the interaction among LINC00467, miR-299-5p and USP48.

RESULTS

LINC00467 was considerably upregulated in HNSCC cells, and an absence of LINC00467 suppressed cell growth, cell migration and the epithelial-mesenchymal process in HNSCC. In addition, miR-299-5p expression was notably downregulated in HNSCC cells, and miR-299-5p could bind with LINC00467. Furthermore, USP48 was conspicuously overexpressed in HNSCC cells and capable of binding with miR-299-5p. LINC00467 could upregulate USP48 expression via sponging miR-299-5p. Finally, rescue assays proved that USP48 overexpression could compensate for the suppressive effects on HNSCC progression mediated by LINC00467 deficiency.

CONCLUSIONS

LINC00467 enhances HNSCC progression by serving as a sponge of miR-299-5p to increase USP48 expression.

Long Noncoding RNA SNHG7 Activates Wnt/β-Catenin Signaling Pathway in Cervical Cancer Cells by Epigenetically Silencing DKK1

Background: Cervical cancer (CC) ranks fourth in cancers that resulted in death among women, accumulating the attention of researchers. It has been ascertained that long noncoding RNAs (lncRNAs) are crucial players in the pathological processes of a host of cancers. And, SNHG7 has been reported to enhance the occurrence of various cancers; however, its function in CC sustains obscure. Aim of the Study: This study explored the function of SNHG7 in CC and further investigates the specific molecular mechanism of SNHG7 in regulating CC. Methods: The levels of SNHG7 in CC cells were reflected by quantitative real-time polymerase chain reaction. The functions of SNHG7 on CC tumorigenesis were explored by colony formation, CCK-8 (Cell Counting Kit-8), EdU (ethynyl deoxyuridine), and Western blot assays. The influences of SNHG7 depletion on the binding of EZH2 to DKK1 promoter and H3K27me3 occupancy in DKK1 promoter were studied by chromatin immunoprecipitation assay. Results: SNHG7 was conspicuously higher expressed in CC cells. Knockdown of SNHG7 was detected to ameliorate the malignant behaviors of CC cells. Importantly, the contribution of SNHG7 to CC development was relied on activated Wnt pathway through DDK1-mediated manner. Furthermore, it was confirmed that SNHG7 silencing weakened the binding of EZH2 to DKK1 promoter as well as the occupancy of H3K27me3 in DKK1 promoter. Conclusions: SNHG7 epigenetically silences DKK1 to exacerbate the malignancy of CC via Wnt/β-catenin signaling pathway.

Long noncoding RNA CERS6-AS1 functions as a malignancy promoter in breast cancer by binding to IGF2BP3 to enhance the stability of CERS6 mRNA

Breast cancer (BC) leads to the highest mortality in women worldwide, characterized by inevitable proliferation and metastasis of BC cells. Mounting evidence confirm that lncRNAs play a significant role in the tumorigenesis and development of BC. lncRNA CERS6-AS1 is a novel discovery, and its role and molecular mechanism in BC has not been studied. In this study, it was discovered that CERS6-AS1 was overexpressed in BC tissues and cells. CERS6-AS1 accelerated cell proliferation and suppressed cell apoptosis in BC. Moreover, molecular mechanism exploration uncovered that there was a positive association between CERS6 and CERS6-AS1 (or IGF2BP3) expression in BC. Furthermore, IGF2BP3 serves as a RNA-binding protein for CERS6-AS1 and CERS6-AS1 promoted CERS6 mRNA stability by binding to IGF2BP3. In the end, rescue experiments verified that overexpression of CERS6 rescues the inhibition of CERS6-AS1 deficiency on BC progression in vitro and vivo. Taken together, these evidences suggested that CERS6-AS1 promoted the progression of BC by binding to IGF2BP3 and thus enhancing the stability of CERS6 mRNA, providing a new underlying therapeutic target for BC to improve prognosis.

LINC01006 promotes cell proliferation and metastasis in pancreatic cancer via miR-2682-5p/HOXB8 axis

Background

Pancreatic cancer (PC) is one of the deadliest cancers about the digestive system. Recent researches have validated that long non-coding RNAs (lncRNAs) play vital roles in various cancers, while the function of LINC01006 in PC is rarely clarified.

Aim of the study

Investigation of the specific role of LINC01006 in PC.

Methods

LINC01006 expression was examined by RT-qPCR. CCK-8, EdU, transwell, wound healing, and western blot assays were carried out to explore the function of LINC01006 in PC. The interaction among LINC01006, miR-2682-5p and HOXB8 was verified by luciferase reporter, RIP and ChIP assays.

Results

The expression of LINC01006 was markedly upregulated in PC tissues and cells. Furthermore, LINC01006 knockdown inhibited PC cell proliferation, invasion and migration, and upregulation of LINC01006 led to the opposite results. Besides, miR-2682-5p expression was downregulated and negatively regulated by LINC01006 in PC. Meanwhile, LINC01006 could bind with miR-2682-5p in PC. Moreover, miR-2682-5p negatively regulated HOXB8 expression and there was a binding site between miR-2682-5p and HOXB8 in PC. Additionally, miR-2682-5p overexpression or HOXB8 knockdown rescued the promotive effects of LINC01006 upregulation on PC cell progression. Similarly, miR-2682-5p inhibition or HOXB8 overexpression countervailed the repressive role of LINC01006 downregulation in PC cell progression. In addition, the transcription factor HOXB8 could activate LINC01006 transcription in PC.

Conclusions

LINC01006 promotes cell proliferation and metastasis in pancreatic cancer via miR-2682-5p/HOXB8 axis, which may facilitate the treatment for PC.

Long noncoding RNA CHL1-AS1 promotes cell proliferation and migration by sponging miR-6076 to regulate CHL1 expression in endometrial cancer

Endometrial cancer (EC) is deemed to be the most typical gynecologic malignant tumor. Despite the incidence of EC being lower in Asia than that in western countries, substantial increased incidence has been observed in the past few decades in Asia. Although various molecular testing methods and genomic science have developed, the overall prognosis is still disappointing. LncRNAs have been found to influence the progression of various cancers. CHL1-AS1 has been found to be upregulated in ovarian endometriosis, nevertheless, the molecular mechanism and biological function of CHL1-AS1 in EC have not been explored. In our exploration, both CHL1-AS1 and CHL1 were upregulated in EC cells. Knockdown of CHL1-AS1 or CHL1 inhibited cell proliferation and migration in EC. Furthermore, microRNA-6076 (miR-6076) could bind with CHL1-AS1 or CHL1, and regulate the expression of CHL1. Finally, absence of miR-6076 or overexpression of CHL1 can partially rescue the effect of CHL1-AS1 knockdown or miR-6076 upregulation on cell proliferation and migration, respectively. All in all, our research was the first endeavor to study the underlying mechanism of CHL1-AS1 in EC and confirmed that CHL1-AS1 regulated EC progression via targeting the miR-6076/CHL1 axis, offering new insight into treating EC.

Exosome-mediated transfer of miR-1290 promotes cell proliferation and invasion in gastric cancer via NKD1

Currently, exosomes rich in RNAs and proteins are regarded as vital mediators of intercellular communication. Here, we aimed to explore the effects of exosomal miR-1290 in gastric cancer (GC) and understand its mechanism of action on GC progression. We first isolated exosomes from serum samples of GC patients and healthy people and characterized them by transmission electron microscopy. Then, we examined the expression level of miR-1290 contained in the exosomes by quantitative reverse-transcription polymerase chain reaction and found that exosomal miR-1290 was overexpressed in GC patients and cell lines. Promotion of proliferation, migration, and invasiveness of GC cells was noted after they were incubated with the isolated miR-1290-rich exosomes compared with incubation with a negative control. Furthermore, we predicted that naked cuticle homolog 1 (NKD1) mRNA is a direct target of miR-1290 and confirmed their interaction by a dual luciferase reporter assay. NKD1 overexpression attenuated the stimulatory effects of miR-1290 on GC cells. Collectively, our results suggest that exosomal miR-1290 enhances GC cell proliferation and invasion by targeting NKD1 mRNA and downregulating NKD1 expression. A better understanding of this process may facilitate the development of novel therapeutic agents for GC.

Long noncoding RNA MIR31HG abrogates the availability of tumor suppressor microRNA-361 for the growth of osteosarcoma

Purpose

Long noncoding RNA (LncRNA) containing microRNA host gene is an interesting type of LncRNA. MicroRNA-31 (miR-31)-host gene LncRNA (MIR31HG) have been recognized as an oncogene in many cancers, but not in osteosarcoma (OS). Interestingly, MIR31HG/miR-31 could not regulate each other’s expression in certain cancer, suggesting that the role of MIR31HG in cancer is independent of miR-31. We here investigated the function and potential mechanism of MIR31HG in OS.

Methods

OS tissues and adjacent non-tumor tissues (n=40) were collected to determine the expressions of MIR31HG by paired t-test. We here identified the miRNAs predicted to be bound to MIR31HG and investigated the impacts of MIR31HG on cell growth and metastasis of OS cells by CCK-8, flow cytometry, Transwell assay, Western blot, etc. in vitro and in vivo.

Results

MIR31HG was upregulated in OS tissues and OS cell lines. The patients with high expression of MIR31HG have high tumor stages and distant metastasis. Tumor suppressor miR-361, but not miR-31, was confirmed to be sponged directly by MIR31HG in OS cells and was down-regulated in OS cell lines. Knockdown of MIR31HG restored the expression of miR-361. Restoration of miR-361 level in Saos-2 and U2OS cells induced cell apoptosis and G1/S arrest, inhibited proliferation and migration, which was, however, abrogated by MIR31HG. Mechanistically, cell growth and metastasis-related target genes of MIR-361 including VEGF, FOXM1 and Twist were de-repressed in OS cells by MIR31HG overexpression, leading to upregulated BCL2, CCND1 and epithelial–mesenchymal transition (EMT) phenotype. Patients with high expression of MIR31HG also showed more VEGF, FOXM1 and Twist levels. Overexpression of MIR31HG in vivo also promoted tumor growth via inhibition of miR-361 signals and elevated the expression of VEGF, FOXM1 and Twist for tumor growth.

Conclusion

MIR31HG acts as an oncogene in OS for tumor progression via regulation of tumor suppressor miR-361 and its target genes.

Predicting lncRNA-miRNA Interaction via Graph Convolution Auto-Encoder

The interaction of miRNA and lncRNA is known to be important for gene regulations. However, the number of known lncRNA-miRNA interactions is still very limited and there are limited computational tools available for predicting new ones. Considering that lncRNAs and miRNAs share internal patterns in the partnership between each other, the underlying lncRNA-miRNA interactions could be predicted by utilizing the known ones, which could be considered as a semi-supervised learning problem. It is shown that the attributes of lncRNA and miRNA have a close relationship with the interaction between each other. Effective use of side information could be helpful for improving the performance especially when the training samples are limited. In view of this, we proposed an end-to-end prediction model called GCLMI (Graph Convolution for novel lncRNA-miRNA Interactions) by combining the techniques of graph convolution and auto-encoder. Without any preprocessing process on the feature information, our method can incorporate raw data of node attributes with the topology of the interaction network. Based on a real dataset collected from a public database, the results of experiments conducted on k-fold cross validations illustrate the robustness and effectiveness of the prediction performance of the proposed prediction model. We prove the graph convolution layer as designed in the proposed model able to effectively integrate the input data by filtering the graph with node features. The proposed model is anticipated to yield highly potential lncRNA-miRNA interactions in the scenario that different types of numerical features describing lncRNA or miRNA are provided by users, serving as a useful computational tool.

miR-5590-3p-YY1 feedback loop promotes the proliferation and migration of triple-negative breast cancer cells

Lacking of diagnostic and prognostic biomarkers is a significant reason for the poor prognosis of patients with triple-negative breast cancer (TNBC). MicroRNAs (miRNAs) have been discovered to engage in the tumorigenesis and development of TNBC. miR-5590-3p has been found to be involved in the development of gastric cancer, but its role and underlying mechanism in TNBC remain obscure. In this study, it was discovered that miR-5590-3p was downregulated in TNBC tissues and cells. Function assays confirmed that miR-5590-3p overexpression inhibited cell proliferation, migration, and epithelial-mesenchymal transition (EMT) process as well as promoted cell apoptosis in TNBC. Moreover, YY1 could bind with the promoter of miR-5590-3p and overexpression of YY1 inhibited the transcription of miR-5590-3p. It was found that YY1 acted as a downstream target gene to bind with miR-5590-3p and was negatively regulated by miR-5590-3p. Finally, it was discovered that overexpression of YY1 could partially rescue the miR-5590-3p overexpression-mediated inhibitive effect on TNBC progression. Taken together these results, it can be concluded that miR-5590-3p-YY1 feedback loop promoted the proliferation and migration of TNBC.

LINC01579 promotes cell proliferation by acting as a ceRNA of miR-139-5p to upregulate EIF4G2 expression in glioblastoma

Glioblastoma (GBM), a malignant and lethal tumor, remains a big threat to human health and life. Increasing explorations have confirmed that long noncoding RNAs are involved in the tumorigenesis and development of multiple cancers. Nevertheless, the regulatory mechanism of (long intergenic nonprotein coding RNA 1579 LINC01579) in GBM remains to be investigated. In this study, the expression of LINC01579 was upregulated in GBM cells and LINC01579 knockdown inhibited cell proliferation as well as promoted cell apoptosis. Additionally, LINC01579 acted as a sponge for miR-139-5p in GBM and eukaryotic translation initiation factor 4 gamma 2 (EIF4G2) was found to be a downstream target of miR-139-5p. Furthermore, the positive correlation of LINC01579 and EIF4G2 as well as the converse correlation between miR-139-5p and LINC01579 (or EIF4G2) were revealed by the experiments. Based on rescue assays, EIF4G2 overexpression or miR-139-5p inhibitor partially recovered the function of LINC01579 knockdown on cell proliferation and apoptosis. In summary, the results of this study verified that LINC01579 modulated cell proliferation and cell apoptosis in GBM by competitively binding with miR-139-5p to regulate EIF4G2, which provided a new clue to figure out potential therapy for patients suffered from GBM.

MiR-644a Disrupts Oncogenic Transformation and Warburg Effect by Direct Modulation of Multiple Genes of Tumor-Promoting Pathways

Castration-resistant prostate cancer (CRPC) is defined by tumor microenvironment heterogeneity affecting intrinsic cellular mechanisms including dysregulated androgen signaling, aerobic glycolysis (Warburg effect), and aberrant activation of transcription factors including androgen receptor (AR) and c-Myc. Using in vitro, in vivo, and animal models, we find a direct correlation between miR-644a downregulation and dysregulation of essential cellular processes. MiR-644a downregulated expression of diverse tumor microenvironment drivers including c-Myc, AR coregulators, and antiapoptosis factors Bcl-xl and Bcl2. Moreover, miR-644a modulates epithelial-mesenchymal transition (EMT) by directly targeting EMT-promoting factors ZEB1, cdk6, and Snail. Finally, miR-644a expression suppresses the Warburg effect by direct targeting of c-Myc, Akt, IGF1R, and GAPDH expression. RNA sequencing analysis revealed an analogous downregulation of these factors in animal tumor xenografts. These data demonstrate miR-644a mediated fine-tuning of oncogenesis, stimulating pathways and resultant potentiation of enzalutamide therapy in CRPC patients. SIGNIFICANCE: This study demonstrates that miR-644a therapeutically influences the CRPC tumor microenvironment by suppressing androgen signaling and additional genes involved in metabolism, proliferation, Warburg effect, and EMT, to potentiate the enzalutamide therapy.Graphical Abstract: http://cancerres.aacrjournals.org/content/canres/79/8/1844/F1.large.jpg.

SNHG1 promotes malignant biological behaviors of glioma cells via microRNA-154-5p/miR-376b-3p- FOXP2- KDM5B participating positive feedback loop

Background

Long non-coding RNAs has been reported in tumorigenesis and play important roles in regulating malignant behavior of cancers, including glioma.

Methods

According to the TCGA database, we identified SNHG1, miRNA-154-5p and miR-376b-3p whose expression were significantly changed in the glioma samples. Furthermore, we investigated SNHG1, miRNA-154-5p and miR-376b-3p expression in clinical samples and glioma cell lines using qRT-PCR analysis and the correlation between them using RNA immunoprecipitation and dual-luciferase reporter. The underlying mechanisms of SNHG1 in glioma were also investigated using immunohistochemistry staining, Western blotting, chromatin immunoprecipitation, and RNA pulldown. Cell Counting Kit-8, transwell assays, and flow cytometry were used to investigate malignant biological behaviors.

Results

We have elucidated the potential molecular mechanism of long non-coding RNA SNHG1 regulating the malignant behavior of glioma cells by binding to microRNA-154-5p or miR-376b-3p. Moreover, our deep-going results showed that FOXP2 existed as a direct downstream target of both microRNA-154-5p and miR-376b-3p; FOXP2 increased promoter activities and enhanced the expression of the oncogenic gene KDM5B; and KDM5B also acts as a RNA-binding protein to maintain the stability of SNHG1.

Conclusion

Collectively, this study demonstrates that the SNHG1- microRNA-154-5p/miR-376b-3p- FOXP2- KDM5B feedback loop plays a pivotal role in regulating the malignant behavior of glioma cells.

Graphical abstract

Electronic supplementary material

The online version of this article (10.1186/s13046-019-1063-9) contains supplementary material, which is available to authorized users.

Dysregulation of ncRNAs located at the DLK1‑DIO3 imprinted domain: involvement in urological cancers

Genomic imprinting has been found to be involved in human physical development and several diseases. The DLK1-DIO3 imprinted domain is located on human chromosome 14 and contains paternally expressed protein-coding genes (DLK1, RTL1, DIO3) and numerous maternally expressed ncRNA genes (MEG3, MEG8, antisense RTL1, miRNAs, piRNAs, and snoRNAs). Emerging evidence has implicated that dysregulation of the DLK1-DIO3 imprinted domain especially the imprinted ncRNAs is critical for tumor progressions. Multiple miRNAs and lncRNAs have been investigated in urological cancers, of which several are transcribed from this domain. In this review, we present current data about the associated miRNAs, lncRNAs, and piRNAs and the regulation of differentially methylated regions methylation status in the progression of urological cancers and preliminarily propose certain concepts about the potential regulatory networks involved in DLK1-DIO3 imprinted domain.

The novel regulatory role of lncRNA-miRNA-mRNA axis in cardiovascular diseases

Long noncoding RNAs (lncRNAs) are RNAs longer than 200 nt in length that are characterized by low levels of sequence conservation and expression; lncRNAs modulate various biological functions at epigenetic, transcriptional and post-transcriptional levels, or directly regulate protein activity. As a family of small and evolutionarily conserved noncoding RNAs, microRNAs (miRNAs) are capable of regulating physiological and pathological processes via inhibiting target mRNA translation or promoting mRNA degradation. A number of studies have confirmed that both lncRNAs and miRNAs are closely associated with the development of cardiovascular diseases (CVDs), such as cardiac remodelling, heart failure, myocardial injury and arrhythmia, and that they act as biomarkers, potential therapeutic targets or strong indicators of prognosis; however, the underlying molecular mechanism has not been elucidated. Recently, emerging evidence showed that the novel regulatory mechanism underlying the crosstalk among lncRNAs, miRNAs and mRNAs plays a pivotal role in the pathophysiological processes of CVDs in response to stress stimuli. In this review, I comprehensively summarized the regulatory relationship of lncRNAs, miRNAs and mRNAs and highlighted the important role of the lncRNA-miRNA-mRNA axis in CVDs.

Negative Regulation of Kruppel-Like Factor 4 on microRNA-106a at Upstream Transcriptional Level and the Role in Gastric Cancer Metastasis

BACKGROUND

MicroRNAs are classes of endogenous noncoding RNAs that play a substantial role in tumor processes through regulating the targets at posttranscriptional level. However, little is known about the upstream transcription regulatory mechanism although it is a prerequisite for investigation of its aberrant expression and function.

AIMS

This report evaluates miR-106a's direct transcriptional factor from upstream level to in depth elucidate their communication in gastric cancer development.

METHODS

Gastric cancer tissues were collected to analyze the miR-106a expression using real-time PCR methods. The combination of Kruppel (or Krüppel)-like factor 4 (KLF4) to miR-106a promoter was testified through bioinformatics followed by construction of luciferase reporter plasmid and chromatin immunoprecipitation assay. Functional experiments and mouse models for evaluating cell growth and metastasis were conducted to observe the biological effect of KLF4 on miR-106a. The interplay between KLF4 and miR-106a was tested with Wnt activator and confirmed in clinical specimens.

RESULTS

The up-regulated miR-106a linked to gastric cancer metastasis and epithelial-mesenchymal transition. UCSC and JASPAR predicted the promoter sequence of miR-106a and its binding site with transcriptional factor KLF4. Construction of reporter gene further verified their direct combination at upstream level. Moreover, the inhibitory effect of KLF4 on the phenotype of gastric cancer cells could be restored by miR-106a. CHIR-induced experiment and clinical specimens confirmed the negative regulation of KLF4 on miR-106a.

CONCLUSIONS

Our findings provide novel direct insights into molecular mechanisms for interaction of KLF4 and miR-106a at upstream level and new ways for clinical application of KLF4-miR-106a axis in advanced gastric cancer metastasis.

LINC00152 promotes the growth and invasion of oral squamous cell carcinoma by regulating miR-139-5p

Background

LINC00152 plays a crucial role in tumorigenesis and progression of multiple types of cancer. However, the biological significance of LINC00152 and its potential role in oral squamous cell carcinoma (OSCC) remain to be determined. In the present study, we investigated the role of LINC00152 and the underlying mechanism of its oncogenic activity in OSCC.

Materials and methods

The expression of LINC00152 in OSCC tissues and cell lines was detected using qRT-PCR. Cell proliferation, colony formation, migration, and invasion were measured using a cell counting kit, colony formation assay, wound healing, and transwell invasion assays, respectively. The target gene of LINC00152 was confirmed using a dual-luciferase reporter assay and qRT-PCR. A nude mouse model was established to analyze the function of LINC00152 in vivo.

Results

LINC00152 expression was significantly upregulated in OSCC tissues and cell lines compared with that in normal counterparts. Upregulated LINC00152 served as an independent prognostic predictor in patients with OSCC. Moreover, knockdown of LINC00152 inhibited cell proliferation, colony formation, migration, and invasion, and suppressed the epithelial to mesenchymal transition in vitro, as well as impairing tumor growth in vivo. A mechanistic investigation indicated that LINC00152 could directly bind to miR-139-5p in OSCC. LINC00152 expression was inversely correlated with miR-139 expression in OSCC tissues.

Conclusion

Taken together, these results suggested that LINC00152 may function as oncogene in OSCC and could be a potential therapeutic target in patients with OSCC.

The novel long noncoding RNA u50535 promotes colorectal cancer growth and metastasis by regulating CCL20

Long noncoding RNAs (lncRNAs) have been emerging as master regulators of tumor growth and metastasis, but the functions and underlying mechanisms of lncRNAs in colorectal cancer (CRC) still need to be clarified. Here, we found a novel lncRNA u50535, which was greatly overexpressed in CRC tissues and was associated with poor prognosis in CRC patients. Function studies showed that u50535 was an oncogene in CRC both in vitro and in vivo. In mechanism, through RNA sequencing and rescue assay, we found that u50535 activates CCL20 signaling to promote cell proliferation and migration in CRC. Taken together, these findings suggest that u50535 can promote CRC growth and metastasis and may serve as a potential biomarker in CRC.