Long Non-Coding RNA JPX Contributes to Tumorigenesis by Regulating miR-5195-3p/VEGFA in Non-Small Cell Lung Cancer

A Novel ceRNET Relying on the lncRNA JPX, miR-378a-3p, and Its mRNA Targets in Lung Cancer

Lung cancer is the leading cause of cancer-related death worldwide. Non-coding RNAs are emerging as critical players for the onset and progression of cancer. Analyses of three different datasets revealed that the lncRNA JPX was overexpressed in adenocarcinoma tissues in comparison to normal lungs, as expected for an oncogene. Intriguingly, the predicted binding miR-378a-3p showed a significant inverse correlation with JPX expression. The lncRNA/miRNA physical interaction was validated by reporter vectors. Then, the oncogenic activity of JPX, the tumor-suppressive role of miR-378a-3p, and the contribution of their functional interaction to cancer hallmarks were demonstrated using assays for cell proliferation, migration, invasion, and 3D-spheroid formation. Finally, molecular circuits were investigated by boosting the expression of both JPX and miR-378a-3p, singularly and in combination, demonstrating that JPX counteracted miR-378a-3p silencing activity toward its oncogenic targets GLUT1, NRP1, YY1, and Wnt5a. Overall, the data unveil a novel ceRNET (competing endogenous RNA network), wherein JPX acts as a ceRNA by binding to miR-378a-3p, thus reducing the miRNA silencing activity toward its downstream targets, and eliciting oncogenic pathways driving lung cancer. The knowledge of the network may pave the way to develop new diagnostic panels, and innovative RNA-targeted and RNA-based therapeutic strategies.

CircRUNX1 drives the malignant phenotypes of lung adenocarcinoma through mediating the miR-5195-3p/HMGB3 network

BACKGROUND

Circular RNAs (circRNAs) are key factors in the regulation of cancer progression. However, the role of circRUNX1 in lung adenocarcinoma (LUAD) progression is unclear.

METHODS

The expression levels of circRUNX1, microRNA (miR)-5195-3p, and high-mobility group protein B3 (HMGB3) were detected by quantitative real-time PCR. Cell proliferation, migration, invasion and apoptosis were analyzed by EdU staining, colony formation assay, transwell assay and flow cytometry. Protein levels were measured using western blot analysis. The interaction between miR-5195-3p and circRUNX1 or HMGB3 was verified by dual-luciferase reporter assay and RIP assay. Animal experiments were performed to investigate the role of circRUNX1 in LUAD tumorigenesis.

RESULTS

We found that circRUNX1 was upregulated in LUAD tumor tissues and cells. CircRUNX1 knockdown suppressed LUAD cell proliferation and metastasis, while promoted apoptosis. In terms of mechanism, we found that circRUNX1 could sponge miR-5195-3p, and miR-5195-3p inhibitor abolished the regulation of circRUNX1 knockdown on LUAD cell proliferation, metastasis and apoptosis. In addition, miR-5195-3p could target HMGB3, and HMGB3 overexpression reversed the inhibition effect of miR-5195-3p on LUAD progression. Moreover, circRUNX1 knockdown reduced LUAD tumorigenesis.

CONCLUSION

CircRUNX1 facilitated LUAD proliferation and metastasis by regulating the miR-5195-3p/HMGB3 axis, suggesting that it might be a possible therapeutic target for LUAD.

Circ_0007351 Exerts an Oncogenic Role In Colorectal Cancer Depending on the Modulation of the miR-5195-3p/GPRC5A Cascade

Circular RNAs (circRNAs) exert critical functions in colorectal cancer development. In this work, we wanted to elucidate the functional role and regulatory mechanism of circ_0007351 in colorectal cancer. For quantification of circ_0007351, microRNA (miR)-5195-3p and G Protein-coupled receptor class C group 5 member A (GPRC5A), a qRT-PCR, immunoblotting or immunohistochemistry assay was performed. Effects of circ_0007351/miR-5195-3p/GPRC5A cascade were evaluated by determining cell viability, proliferation, colony formation, motility, and invasion. Relationships among variables were assessed by dual-luciferase reporter assay. Animal studies were performed to evaluate circ_0007351's function in the growth of xenograft tumors. Circ_0007351 was markedly up-regulated in colorectal cancer tissues and cells. Down-regulation of circ_0007351 hindered cell growth, migration and invasiveness. Also, circ_0007351 depletion exerted a suppressive function in colorectal cell xenograft growth in vivo. Mechanistically, circ_0007351 sponged miR-5195-3p to sequester miR-5195-3p. Reduction of available miR-5195-3p neutralized the effects of circ_0007351 down-regulation on cell phenotypes. MiR-5195-3p directly targeted and inhibited GPRC5A. Circ_0007351 regulated GPRC5A expression by sponging miR-5195-3p. Moreover, the effects of circ_0007351 down-regulation on cell functional phenotypes were due to in part the reduction of GPRC5A expression. Our findings show that circ_0007351 down-regulation impedes proliferation, motility, and invasiveness in colorectal cancer cells at least in part via the regulation of the miR-5195-3p/GPRC5A cascade, highlighting that circ_0007351 inhibition may have a potential therapeutic value for colorectal cancer.

MicroRNA-299-3p inhibits cell proliferation, motility, invasion and angiogenesis via VEGFA in upper tract urothelial carcinoma

BACKGROUND

Upper tract urothelial carcinoma (UTUC) is a rare tumor with extraordinarily different features between Eastern and Western countries. Vascular endothelial growth factor-A (VEGFA) was originally identified as a secreted signaling protein and regulator of vascular development and cancer progression. In this study, we aimed to elucidate the molecular mechanisms underlying the regulation of VEGFA by microRNA in UTUC.

METHODS

VEGFA expression was evaluated by immunohistochemistry in 140 human UTUC tissue samples. Next, we assessed the regulatory relationship between VEGFA and miR-299-3p by real-time PCR, western blotting, ELISA and dual-luciferase reporter assays using two UTUC cell lines. The role of miR-299-3p/VEGFA in cell proliferation, motility, invasion, and tube formation was analyzed in vitro.

RESULTS

High VEGFA expression was significantly associated with tumor stage, grade, distant metastasis and cancer-related death and correlated with poor progression-free and cancer-specific survival. VEGFA knockdown repressed proliferation, migration, invasion and angiogenesis in UTUC cell lines. miR-299-3p significantly reduced VEGFA protein expression and miR-299-3p overexpression inhibited VEGFA mRNA and protein expression by directly targeting its 3'-UTR. Functional studies indicated that VEGFA overexpression reversed the miR-299-3p-mediated suppression of tumor cell proliferation, migration, invasion and angiogenesis. In addition, miR-299-3p/VEGFA suppressed cellular functions in UTUC by modulating the expression of P18 and cyclin E2.

CONCLUSIONS

Our findings suggest that miR-299-3p possibly suppresses UTUC cell proliferation, motility, invasion and angiogenesis via VEGFA. VEGFA may act as a prognostic predictor, and both VEGFA and miR-299-3p could be potential therapeutic targets for UTUC.

Luteolin Pretreatment Ameliorates Myocardial Ischemia/Reperfusion Injury by lncRNA-JPX/miR-146b Axis

Background

In the present study, we aimed to find out whether luteolin (Lut) pretreatment could ameliorate myocardial ischemia/reperfusion (I/R) injury by regulating the lncRNA just proximal to XIST (JPX)/microRNA-146b (miR-146b) axis.

Methods

We established the models in vitro (HL-1 cells) and in vivo (C57BL/6J mice) to certify the protection mechanism of Lut pretreatment on myocardial I/R injury. Dual luciferase reporter gene assay was utilized for validating that JPX could bind to miR-146b. JPX and miR-146b expression levels were determined by RT-qPCR. Western blot was utilized to examine apoptosis-related protein expression levels, including cleaved caspase-9, caspase-9, cleaved caspase-3, caspase-3, Bcl-2, Bax, and BAG-1. Apoptosis was analyzed by Annexin V-APC/7-AAD dualstaining, Hoechst 33342 staining, as well as flow cytometry. Animal echocardiography was used to measure cardiac function (ejection fraction (EF) and fractional shortening (FS) indicators).

Results

miR-146b was demonstrated to bind and recognize the JPX sequence site by dual luciferase reporter gene assay. The expression level of miR-146b was corroborated to be enhanced by H/R using RT-qPCR (P < 0.001 vs. Con). Moreover, JPX could reduce the expression of miR-146b, whereas inhibiting JPX could reverse the alteration (P < 0.001 vs. H/R, respectively). Western blot analysis demonstrated that Lut pretreatment increased BAG-1 expression level and Bcl-2/Bax ratio, but diminished the ratio of cleaved caspase 9/caspase 9 and cleaved caspase 3/caspase 3 (P < 0.001 vs. H/R, respectively). Moreover, the cell apoptosis change trend, measured by Annexin V-APC/7-AAD dualstaining, Hoechst 33342 staining, along with flow cytometry, was consistent with that of apoptosis-related proteins. Furthermore, pretreatment with Lut improved cardiac function (EF and FS) (P < 0.001 vs. I/R, respectively), as indicated in animal echocardiography.

Conclusion

Our results demonstrated that in vitro and in vivo, Lut pretreatment inhibited apoptosis via the JPX/miR-146b axis, ultimately improving myocardial I/R injury.

MiR-5195-3p functions as a tumor suppressor by targeting RHBDD1 in ovarian cancer

BACKGROUND

Recent studies have reported the tumor suppressive role of miR-5195-3p in the progression of several cancers, but the potential roles of miR-5195-3p in ovarian cancer (OC) remain largely unknown.

METHODS

We first analyzed the expression levels of miR-5195-3p in 83 pairs of human OC tissues and adjacent specimens by reverse transcription-quantitative PCR. The correlation of miR-5195-3p/rhomboid domain containing 1 (RHBDD1) and clinicopathological parameters was analyzed by chi-square test. The prognostic value of miR-5195-3p was evaluated by Kaplan-Meier method Cox proportional hazards models. The effects of miR-5195-3p on cell proliferation, cell cycle distribution, migration and invasion were examined by CCK-8 assay, colony formation assay, flow cytometry and transwell assay. Tumor forming was evaluated by nude mice model in vivo. The association between miR-5195-3p and RHBDD1 was verified by luciferase reporter assay.

RESULTS

We observed that miR-5195-3p level was remarkably reduced in OC tissues as compared to adjacent tissues. The expression of miR-5195-3p was associated with FIGO stage, depth of invasion and poor survival prognosis in OC patients. Overexpression of miR-5195-3p significantly suppressed cell proliferation, cell cycle G1/S transition, migration and invasion in OC cell lines (SKOV-3 and OVCAR3), while knockdown of miR-5195-3p obtained the opposite results. We further confirmed miR-5195-3p as a negative post-transcriptional modulator of RHBDD1. RHBDD1 expression was upregulated in OC tissues compared with adjacent tissues, which was inversely correlated with miR-5195-3p expression. The expression of RHBDD1 was associated with FIGO stage and distant metastasis. RHBDD1 overexpression reversed the suppressive role of miR-5195-3p on OC cell proliferation, migration and invasion. Consistent with the in vitro results, miR-5195-3p overexpression decreased the growth of subcutaneously inoculated tumors in nude mice.

CONCLUSIONS

Taken together, the present results indicated that miR-5195-3p acts a tumor suppressor by targeting RHBDD1 in OC.

circWHSC1: A circular RNA piece in the human cancer puzzle

Circular RNAs (circRNAs) are a group of non-coding RNAs with a closed loop shape, which are transcribed via non-canonical splicing. They are mainly formed by reverse splicing of a precursor mRNA. circWHSC1 (Hsa_circ_0001387), is a cancer-related circRNA that originated from the Wolf-Hirschhorn syndrome candidate 1 (WHSC1) gene on chromosome 4. circWHSC1 has been found to be overexpressed in different neoplastic conditions. circWHSC1 acts as a sponge for many different miRNAs, including miR-195-5p, miR-532-3p, miR-646, miR-142-3p, miR-7, miR-296-3p, miR-145, miR-1182, miR-212-5p, etc. It can also moderate several signaling pathways, including FASN/AMPK/mTOR, LTBP2, NPM1, HOXA1, TAB2, AKT3, hTERT, and MUC1. Studies have shown that circWHSC1 may leads to an increase in cell growth, tumor size, cell migration, invasion, and metastasis, but a reduction in apoptosis rates. Moreover, upregulation of CircWHSC1 has been associated with reduced patient's survival in different cancers, representing the function of this circRNA as a novel prognostic marker. Nevertheless, there are no reviews focusing on the relationship between circWHSC1 and cancers. Therefore, in the current review, we will first describe the oncogenic effect of circWHSC1 in various tissues according to the evidence from in vitro, in vivo, and human studies.

MiR-5195-3p targets the PCBP2/PI3K/AKT pathway to inhibit melanoma cell proliferation and migration

Although miR-5195-3p has been acknowledged for its tumor suppressor role in diverse cancer categories, its precise functions and mechanisms concerning melanoma have not been comprehensively elucidated. In this study, we employed quantitative reverse transcription PCR, Western blot analysis, and immunohistochemistry staining to investigate the expression patterns of miR-5195-3p and poly (rC) binding protein 2 (PCBP2) in melanoma tissues compared to adjacent tissues. Our findings revealed downregulation of miR-5195-3p and upregulation of PCBP2 in melanoma tissues. Through the implementation of a luciferase reporter assay, we successfully identified PCBP2 as a newly discovered target of miR-5195-3p in melanoma cells. Enforced expression of miR-5195-3p via mimics inhibited cell proliferation and migration in A375 and A2058 cells, as demonstrated by CCK-8 and transwell migration assays. In melanoma cells, reintroduction of PCBP2 partially reversed the inhibitory effects of miR-5195-3p overexpression. Treatment with LY294002, an inhibitor of the PI3K/AKT signaling pathway, also reversed the effects of PCBP2 in melanoma cells. Furthermore, our results suggest that miR-5195-3p inhibits the activation of the PI3K/AKT signaling pathway in melanoma by inhibiting PCBP2. In conclusion, our research has identified the miR-5195-3p targeting of the PCBP2-mediated PI3K/AKT signaling pathway as a potential therapeutic target for melanoma treatment.

Emerging role of long non-coding RNA JPX in malignant processes and potential applications in cancers

ABSTRACT

Long non-coding RNAs (lncRNAs) reportedly function as important modulators of gene regulation and malignant processes in the development of human cancers. The lncRNA JPX is a novel molecular switch for X chromosome inactivation and differentially expressed JPX has exhibited certain clinical correlations in several cancers. Notably, JPX participates in cancer growth, metastasis, and chemoresistance, by acting as a competing endogenous RNA for microRNA, interacting with proteins, and regulating some specific signaling pathways. Moreover, JPX may serve as a potential biomarker and therapeutic target for the diagnosis, prognosis, and treatment of cancer. The present article summarizes our current understanding of the structure, expression, and function of JPX in malignant cancer processes and discusses its molecular mechanisms and potential applications in cancer biology and medicine.

Cuproptosis-related LncRNAs are potential prognostic and immune response markers for patients with HNSCC via the integration of bioinformatics analysis and experimental validation

Introduction

Head and neck squamous cell carcinoma (HNSCC) is a malignant neoplasm typically induced by alcohol and tobacco consumption, ranked the sixth most prevalent cancer globally. This study aimed to establish a cuproptosis-related lncRNA predictive model to assess the clinical significance in HNSCC patients.

Methods

The Cancer Genome Atlas (TCGA) database was utilized to download cuproptosis-related genes, lncRNAs profiles, and selected clinical information of 482 HNSCC samples. Cuproptosis-related lncRNAs were analyzed by Pearson correlation method, with the least absolute shrinkage and selection operator (LASSO) and univariate/multivariate Cox analyses performed to establish the cuproptosis-related lncRNA predictive model. Subsequently, the time-dependent receiver operating characteristics (ROC) and Kaplan-Meier analysis were applied to assess its prediction ability, and the model was verified by a nomogram, univariate/multivariate Cox analysis, and calibration curves. Furthermore, the principal component analysis (PCA), immune analysis, and gene set enrichment analyses (GSEA) were performed, and the 50% inhibitory concentration (IC50) prediction in the risk groups was calculated. Furthermore, the expression of six cuproptosis-related lncRNAs in HNSCC and paracancerous tissues was detected by quantitative real-time PCR (qRT-PCR).

Results

A total of 467 lncRNAs were screened as cuproptosis-associated lncRNAs in HNSCC tissues to establish an eight cuproptosis-related lncRNA prognostic signature consisting of AC024075.3, AC090587.2, AC116914.2, AL450384.2, CDKN2A-DT, FAM27E3, JPX, and LNC01089. For the high-risk group, the results demonstrated a satisfactory predicting performance with considerably worse overall survival (OS). Multivariate Cox regression confirmed that the risk score was a reliable predictive factor (95% CI: 1.089-1.208, hazard ratio =1.147), with the area of 1-, 3-, and 5-year OS under the ROC curve of 0.690, 0.78524, and 0.665, respectively. The differential analysis revealed that JPX was significantly upregulated in HNSCC tissues, while AC024075.3, AC090587.2, AC116914.2, AL450384.2, CDKN2A-DT were downregulated in HNSCC tissues by qRT-PCR assays. In addition, this gene signature was also associated with some immune-related pathways and immune cell infiltration and affected the anti-cancer immune response. Furthermore, Bexarotene, Bleomycin, Gemcitabine, etc., were identified as potential therapeutic compounds for HNSCC.

Discussions

This novel cuproptosis-related lncRNAs prognostic signature could predict prognosis and help propose novel individual therapeutic targets for HNSCC.

An innovative pyroptosis-related long-noncoding-RNA signature predicts the prognosis of gastric cancer via affecting immune cell infiltration landscape

Background: Gastric cancer (GC) is a worldwide popular malignant tumor. However, the survival rate of advanced GC remains low. Pyroptosis and long non-coding RNAs (lncRNAs) are important in cancer progression. Thus, we aimed to find out a pyroptosis-related lncRNAs (PRLs) signature and use it to build a practical risk model with the purpose to predict the prognosis of patients with GC. Methods: Univariate Cox regression analysis was used to identify PRLs linked to GC patient's prognosis. Subsequently, to construct a PRLs signature, the least absolute shrinkage and selection operator regression, and multivariate Cox regression analysis were used. Kaplan-Meier analysis, principal component analysis, and receiver operating characteristic curve analysis were performed to assess our novel lncRNA signature. The correlation between risk signature and clinicopathological features was also examined. Finally, the relationship of pyroptosis and immune cells were evaluated through the CIBERSORT tool and single-sample lncRNA set enrichment analysis (ssGSEA). Results: A PRLs signature comprising eight lncRNAs was discerned as a self-determining predictor of prognosis. GC patients were sub-divided into high-risk and low-risk groups via this risk-model. Stratified analysis of different clinical factors also displayed that the PRLs signature was a good prognosis factor. According to the risk score and clinical characteristics, a nomogram was established. Moreover, the difference between the groups is significance in immune cells and immune pathways. Conclusion: This study established an effective prognostic signature consist of eight PRLs in GC, and constructed an efficient nomogram model. Further, the PRLs correlated with immune cells and immune pathways.

The role of lncRNA just proximal to XIST (JPX) in human disease phenotypes and RNA methylation: The novel biomarker and therapeutic target potential

Increasing evidence suggests that long non-coding RNAs (lncRNAs) are closely related to the initialization and development of human diseases. lncRNA just proximal to XIST (JPX), as a newly identified lncRNA, has been reported to be aberrantly expressed and associated with pathophysiological traits in numerous diseases, particularly cancers. More importantly, JPX has been proven to play important roles in various biological functions, including cell proliferation, migration, invasion, apoptosis, chemoresistance, and differentiation. In addition, we discuss the diverse molecular mechanisms and correlation with RNA methylation of JPX in several cancers. In this Review, we summarize current studies on JPX's roles in diseases and its potential application as a biomarker for both diagnoses and prognoses and a therapeutic target in human diseases.

Prognostic signature of endoplasmic reticulum stress-related long noncoding RNAs in head and neck squamous cell carcinoma: Association with somatic mutation and tumor immune microenvironment

Background/purpose

Analysis of endoplasmic reticulum stress (ERS)-related long noncoding RNAs (LncRNAs) may enable prognostic stratification in patients with head and neck squamous cell carcinoma (HNSCC). This study aimed to comprehensively analyze the ERS-related LncRNAs signature and its effects on the prognosis, tumorigenesis, and tumor immune microenvironment in HNSCC.

Materials and methods

The transcriptome data of HNSCC were obtained from TCGA. Least absolute shrinkage selection operator algorithm, and multivariate Cox regression were used to screen LncRNAs for the signature construction. Somatic mutation, gene enrichment, and immune infiltration analyses were further performed.

Results

458 ERS-related LncRNAs were identified and 55 of which were correlated with HNSCC prognosis. Ten ERS-related LncRNAs were selected to establish a risk prediction signature. When dividing patients into high-risk and low-risk groups by signature score, high-risk group correlated with worse survival rates (hazard ratio = 1.211; 95% confidence interval 1.123-1.306, P < 0.001). The area under the curve was 0.751 and 0.716 in the training and validation cohorts at 3-year. Moreover, high-risk group have increased somatic mutation rates and reduced infiltration abundancy of B cells and CD8+ T cells.

Conclusion

The prognostic signature based on ERS-related LncRNAs may serve as a predictor of altered oncogene mutations and immune microenvironment, which provided an insight into the relationship between ERS, LncRNAs, and tumor progression.

Major Role for Cellular MicroRNAs, Long Noncoding RNAs (lncRNAs), and the Epstein-Barr Virus-Encoded BART lncRNA during Tumor Growth In Vivo

This study assessed the effects of Epstein-Barr virus (EBV) and one form of virally encoded BART long noncoding RNAs (lncRNAs) on cellular expression in epithelial cells grown in vitro and as tumors in vivo determined by high-throughput RNA sequencing of mRNA and small RNAs. Hierarchical clustering based on gene expression distinguished the cell lines from the tumors and distinguished the EBV-positive tumors and the BART tumors from the EBV-negative tumors. EBV and BART expression also induced specific expression changes in cellular microRNAs (miRs) and lncRNAs. Multiple known and predicted targets of the viral miRs, the induced cellular miRs, and lncRNAs were identified in the altered gene set. The changes in expression in vivo indicated that the suppression of growth pathways in vivo reflects increased expression of cellular miRs in all tumors. In the EBV and BART tumors, many of the targets of the induced miRs were not changed and the seed sequences of the nonfunctional miRs were found to have homologous regions within the BART lncRNA. The inhibition of these miR effects on known targets suggests that these induced miRs have reduced function due to sponging by the BART lncRNA. This composite analysis identified the effects of EBV on cellular miRs and lncRNAs with a functional readout through identification of the simultaneous effects on gene expression. Major shifts in gene expression in vivo are likely mediated by effects on cellular noncoding RNAs. Additionally, a predicted property of the BART lncRNA is to functionally inhibit the induced cellular miRs.

LncRNA JPX contributes to Treg/Th17 imbalance in allergic rhinitis via targeting the miR-378g/CCL5 axis

Aim: T-regulatory (Treg)/T-helper (Th) 17 imbalance contributes to the pathogenesis of allergic rhinitis (AR). Long non-coding RNAs (lncRNAs) participate in the progression of AR. Herein, the effect of lncRNA JP X on Treg/Th17 balance in AR was explored.Methods: CD4+ T cells were isolated from patients with AR and healthy control. The percentage of Treg and Th17 cells were examined by flow cytometry. The levels of JP X, miR-378g, CCL5, T GF-β, and IL-17A were tested using qRT-P CR. The protein expression of Foxp3 and RORγt was measured by western blot.Results: The data showed that an imbalance of Treg/Th17 was associated with AR. Upregulation of JP X was found in AR, and knockdown of which improved the imbalance of Treg/Th17. Furthermore, JP X functioned as a sponge of miR-378g to upregulate CCL5. Inhibition of miR-378g reversed the effects on Treg/Th17 induced by silencing of JP X. Moreover, overexpression of CCL5 reversed miR-378g-induced effects.Conclusion: In conclusion, depletion of JP X promoted Treg/Th17 balance in AR via regulating the miR-378g/CCL5 axis. The findings provided a novel therapeutic insight for AR.

Long noncoding RNA LINC01703 exacerbates the malignant properties of non-small-cell lung cancer by upregulating MACC1 in a microRNA-605-3p-mediated manner

Long intergenic nonprotein coding RNA 1703 (LINC01703) has diagnostic significancein lung adenocarcinoma. However, its specific roles in non-small-cell lung cancer(NSCLC) and downstream mechanisms have not been investigated. In the current study,we characterized the role of LINC01703 in NSCLC malignancy and elucidated itsdetailed mechanism of action. LINC01703 expression was measured by qRT-PCR. Theregulatory effects of LINC01703 on the malignancy of NSCLC cells were assessed bymultiple functional experiments. The targeted interaction was confirmed by RNAimmunoprecipitation and luciferase reporter assays. Herein, overexpression ofLINC01703 in NSCLC was indicated in the TCGA database and further proven in ourcohort. Functional studies revealed that knocking down LINC01703 repressed cellproliferation, colony formation, migration and invasion in vitro, which wasaccompanied by the induction of apoptosis. The tumor growth of LINC01703-silencedcells was also inhibited in vivo. Mechanistic analyses revealed that LINC01703functioned as a competing endogenous RNA for microRNA-605-3p (miR-605-3p) inNSCLC cells, which thereby upregulated the miR-605-3p target metastasis associatedwith colon cancer 1 (MACC1). Rescue experiments highlighted that the regulatoryactions of LINC01703 ablation on NSCLC cells were abolished in response to miR-605-3p downregulation or MACC1 overexpression. In conclusion, LINC01703enhanced the aggressiveness of NSCLC cells by altering miR-605-3p/MACC1. Ourwork suggests the therapeutic potential of LINC01703/miR-605-3p/MACC1 in NSCLC.

CircRNA WHSC1 promotes non-small cell lung cancer progression via sponging microRNA-296-3p and up-regulating expression of AKT serine/threonine kinase 3

Background

Lung cancer is the most commonly diagnosed cancer and leading cause of cancer death, with 80%–85% of non‐small cell lung cancer (NSCLC). Circular RNAs (circRNAs) have been shown to be promising early diagnostic and therapeutic molecular biomarkers for NSCLC. However, biological role and regulatory mechanism of circRNA WHSC1 (circWHSC1) in NSCLC are unknown. Therefore, we aim to explore the function and mechanism of circWHSC1 in NSCLC oncogenesis and progression.

Methods

qRT‐PCR was used for circWHSC1 level evaluation; Kaplan‐Meier was used for survival analysis; bioinformatics, dual‐luciferase activity, and RNA pull‐down were used for evaluating competing endogenous RNA (ceRNA) network; cell viability, colony formation, apoptosis, migration, and invasion were used for cell function analysis; function gain and loss with rescue experiments were used for exploring mechanism of circWHSC1 in NSCLC development.

Results

Significantly up‐regulated circWHSC1 and down‐regulated microRNA‐296‐3p (miR‐296‐3p) were identified in NSCLC tissues and cells. Up‐regulated circWHSC1 was associated with poor prognosis in NSCLC patients. MiR‐296‐3p was sponged by circWHSC1, and AKT serine/threonine kinase 3 (AKT3) was target of miR‐296‐3p; meanwhile, miR‐296‐3p over‐expression significantly down‐regulated AKT3 expression, and co‐transfecting anti‐miR‐296‐3p rescued circWHSC1 silence caused AKT3 down‐regulation. CircWHSC1 silence significantly inhibited colony formation, viability, invasion, and migration, while increased NSCLC cell apoptosis, which were partially rescued by anti‐miR‐296‐3p.

Conclusion

CircWHSC1 is an independent indicator of poor prognosis in NSCLC patients, and functions as a ceRNA of miR‐296‐3p to up‐regulate AKT3, consequently promotes NSCLC cell growth and metastasis. Targeting circWHSC1 might be a prospective strategy for diagnosis, therapeutics, and prognosis of NSCLC.

Comparative Transcriptional Analysis of Pulmonary Arterial Hypertension Associated With Three Different Diseases

Pulmonary arterial hypertension (PAH) is a severe cardiovascular disorder with high mortality. Multiple clinical diseases can induce PAH, but the underlying molecular mechanisms shared in PAHs associated with different diseases remain unclear. The aim of this study is to explore the key candidate genes and pathways in PAH associated with congenital heart disease (CHD-PAH), PAH associated with connective tissue disease (CTD-PAH), and idiopathic PAH (IPAH). We performed differential expression analysis based on a public microarray dataset GSE113439 and identified 1,442 differentially expressed genes, of which 80.3% were upregulated. Subsequently, both pathway enrichment analysis and protein–protein interaction network analysis revealed that the “Cell cycle” and “DNA damage” processes were significantly enriched in PAH. The expression of seven upregulated candidate genes (EIF2AK2, TOPBP1, CDC5L, DHX15, and CUL1–3) and three downregulated candidate genes (DLL4, EGFL7, and ACE) were validated by qRT-PCR. Furthermore, cell cycle-related genes Cul1 and Cul2 were identified in pulmonary arterial endothelial cells (PAECs) in vitro. The result revealed an increased expression of Cul2 in PAECs after hypoxic treatment. Silencing Cul2 could inhibit overproliferation and migration of PAECs in hypoxia. Taken together, according to bioinformatic analyses, our work revealed that “Cell cycle” and “DNA damage” process-related genes and pathways were significantly dysregulated expressed in PAHs associated with three different diseases. This commonality in molecular discovery might broaden the genetic perspective and understanding of PAH. Besides, silencing Cul2 showed a protective effect in PAECs in hypoxia. The results may provide new treatment targets in multiple diseases induced by PAH.

LNC00115 Mediates Cisplatin Resistance by Regulating the miR-7/ERK Signalling Pathway in Ovarian Cancer

Background

Ovarian cancer has one of the highest mortality rates among all gynaecological malignancies, and increasing evidence suggests that lncRNAs are widely involved in the development of ovarian tumours. This study aimed to investigate the mechanism of the LNC00115/miR-7/ERK axis in the cisplatin resistance of ovarian cancer cells.

Methods

The expression of miR-7 and LNC00115 in ovarian cancer cell lines and tissues was detected by qRT-PCR. The ovarian cancer cell lines were constructed by overexpressing or knocking down the expression of LNC00115 or miR-7. CCK-8, transwell invasion, Western blot, immunohistochemistry, and luciferase reporter assays were carried out to identify the targets of LNC00115 and explore its roles and mechanisms in ovarian cancer. A nude mouse model was established, and the expression of LNC00115, miR-7 and ERK was detected. The changes in the tumours and body weights of the nude mice were measured.

Results

LNC00115 was upregulated in ovarian cancer tissues and cisplatin-resistant ovarian cancer cells. Moreover, LNC00115 promoted the cisplatin resistance, invasion and migration of ovarian cancer cells. LNC00115 was shown to directly target miR-7, and miR-7 was downregulated in ovarian cancer tissues and cisplatin-resistant ovarian cancer cells. miR-7 inhibited the cisplatin resistance, invasion and migration of ovarian cancer cells and directly targeted ERK. ERK was overexpressed in cisplatin-resistant ovarian cancer cells and ovarian cancer tissues. In animal experiments, overexpression of LNC00115 enhanced the cisplatin resistance of ovarian cancer cells, while miR-7 had the opposite effect. Mechanistically, LNC00115 sponged miR-7 to increase the expression of ERK, which in turn enhanced the cisplatin resistance of ovarian cancer.

Conclusion

Our data clarify the mechanism by which the LNC00115/miR-7/ERK axis promotes cisplatin resistance and provide a new clinical strategy for combating cisplatin resistance in ovarian cancer.