Long non-coding RNA PVT1 and cancer

Copy number variations of stepwise-selected doxorubicin-resistant MCF-7 cell lines

Elimination of cytotoxic effect in cells with multidrug resistance (MDR) phenotype is a situation that is gradually acquired over time and develops through multiple pathways resulting in global phenotypic changes of cells. Although molecular background of the resistance phenotype has widely been studied in the gene expression level, segmental and gene copy number variations (CNVs) have limitedly been documented. Thus, in the present study, we aimed to analyze the CNVs using DNA microarray in the sensitive and two doxorubicin-resistant MCF-7 breast cancer cell lines which had different resistance indices. In the present study, we performed conventional karyotyping and array comparative genomic hybridization (aCGH). Then, results of aCGH data were studied with genomic profiling, comparison analysis and ideogram plotting to evaluate genomic profiles, and the loss and gains of heterozygosity profiles. Next, gene lists for each cell line were compared with the 66-breast cancer-related genes and the multidrug resistance-related genes. aCGH analyses showed that CNV profiles and the copy number of specific genes were dramatically different between these three cell lines. Totally, 6212, 6558, and 11,201 genes were found to be altered in MCF-7, MCF-7/400DOX, and MCF-7/1000DOX genomes, respectively. Amongst the MCF-7/1000DOX had the highest number of altered genes, and doxorubicin resistance may cause differential chromosomal changes depending on the resistance status. DNA microarray would be one of the informative methods used in the studies on the cancer drug resistance in addition to transcriptomic and proteomic level high throughput analysis to define molecular mechanisms of the resistance status.

Long non-coding RNAs in cancer: multifaceted roles and potential targets for immunotherapy

Cancer remains a major global health concern with high mortality rates mainly due to late diagnosis and poor prognosis. Long non-coding RNAs (lncRNAs) are emerging as key regulators of gene expression in human cancer, functioning through various mechanisms including as competing endogenous RNAs (ceRNAs) and indirectly regulating miRNA expression. LncRNAs have been found to have both oncogenic and tumor-suppressive roles in cancer, with the former promoting cancer cell proliferation, migration, invasion, and poor prognosis. Recent research has shown that lncRNAs are expressed in various immune cells and are involved in cancer cell immune escape and the modulation of the tumor microenvironment, thus highlighting their potential as targets for cancer immunotherapy. Targeting lncRNAs in cancer or immune cells could enhance the anti-tumor immune response and improve cancer immunotherapy outcomes. However, further research is required to fully understand the functional roles of lncRNAs in cancer and the immune system and their potential as targets for cancer immunotherapy. This review offers a comprehensive examination of the multifaceted roles of lncRNAs in human cancers, with a focus on their potential as targets for cancer immunotherapy. By exploring the intricate mechanisms underlying lncRNA-mediated regulation of cancer cell proliferation, invasion, and immune evasion, we provide insights into the diverse therapeutic applications of these molecules.

Long non-coding RNA PVT1 regulates TGF-β and promotes the proliferation, migration and invasion of hypopharyngeal carcinoma FaDu cells

Hypopharyngeal carcinoma is one of the malignant tumors of the head and neck with a particularly poor prognosis. Recurrence and metastasis are important reasons for poor prognosis of hypopharyngeal cancer patients, and malignant proliferation, migration, and invasion of tumor cells are important factors for recurrence and metastasis of hypopharyngeal cancer. Therefore, elucidating hypopharyngeal cancer cells' proliferation, migration, and invasion mechanism is essential for improving diagnosis, treatment, and prognosis. Plasmacytoma Variant Translocation 1 (PVT1) is considered a potential diagnostic marker and therapeutic target for tumors. However, it remains unclear whether PVT1 is related to the occurrence and development of hypopharyngeal cancer and its specific mechanism. In this study, the promoting effect of PVT1 on the proliferation, migration, and invasion of hypopharyngeal carcinoma FaDu cells was verified by cell biology experiments and animal studies, and it was found that PVT1 inhibited the expression of TGF-β, suggesting that PVT1 may regulate the occurrence and development of hypopharyngeal carcinoma FaDu cells through TGF-β.

Lnc PVT1 facilitates TGF-β1-induced human cardiac fibroblast activation in vitro and ISO-induced myocardial fibrosis in vivo through regulating MYC

Cardiac fibrosis is a commonly seen pathophysiological process in various cardiovascular disorders, such as coronary heart disorder, hypertension, and cardiomyopathy. Cardiac fibroblast trans-differentiation into myofibroblasts (MFs) is a key link in myocardial fibrosis. LncRNA PVT1 participates in fibrotic diseases in multiple organs; however, its role and mechanism in cardiac fibrosis remain largely unknown. Human cardiac fibroblasts (HCFs) were stimulated with TGF-β1 to induce myofibroblast; Immunofluorescent staining, Immunoblotting, and fluorescence in situ hybridization were used to detect the myofibroblasts phenotypes and lnc PVT1 expression. Cell biological phenotypes induced by lnc PVT1 knockdown or overexpression were detected by CCK-8, flow cytometry, and Immunoblotting. A mouse model of myocardial fibrosis was induced using isoproterenol (ISO), and the cardiac functions were examined by echocardiography measurements, cardiac tissues by H&E, and Masson trichrome staining. In this study, TGF-β1 induced HCF transformation into myofibroblasts, as manifested as significantly increased levels of α-SMA, vimentin, collagen I, and collagen III; the expression level of lnc PVT1 expression showed to be significantly increased by TGF-β1 stimulation. The protein levels of TGF-β1, TGFBR1, and TGFBR2 were also decreased by lnc PVT1 knockdown. Under TGF-β1 stimulation, lnc PVT1 knockdown decreased FN1, α-SMA, collagen I, and collagen III protein contents, inhibited HCF cell viability and enhanced cell apoptosis, and inhibited Smad2/3 phosphorylation. Lnc PVT1 positively regulated MYC expression with or without TGF-β1 stimulation; MYC overexpression in TGF-β1-stimulated HCFs significantly attenuated the effects of lnc PVT1 knockdown on HCF proliferation and trans-differentiation to MFs. In the ISO-induced myocardial fibrosis model, lnc PVT1 knockdown partially reduced fibrotic area, improved cardiac functions, and decreased the levels of fibrotic markers. In addition, lnc PVT1 knockdown decreased MYC and CDK4 levels but increased E-cadherin in mice heart tissues. lnc PVT1 is up-regulated in cardiac fibrosis and TGF-β1-stimulated HCFs. Lnc PVT1 knockdown partially ameliorates TGF-β1-induced HCF activation and trans-differentiation into MFs in vitro and ISO-induced myocardial fibrosis in vivo, potentially through interacting with MYC and up-regulating MYC.

Upregulation of the long noncoding RNA GJA9-MYCBP and PVT1 is a potential diagnostic biomarker for acute lymphoblastic leukemia

BACKGROUND

Acute lymphoblastic leukemia (ALL) is the most common type of blood cancer in children. Aberrant expression of long noncoding RNAs (lncRNAs) may set stages for ALL development. LncRNAs are emerging as a novel diagnostic and prognostic biomarker for ALL. Herein, we aimed to evaluate the expression of lncRNA GJA9-MYCBP and PVT1 in blood samples of ALL and healthy individuals.

METHODS

As a case-control study, 40 pairs of ALL and healthy individual samples were used. The expression of MYC and each candidate lncRNA was measured using quantitative real-time PCR. Any possible association between the expression of putative noncoding RNAs and clinicopathological characteristics was also evaluated.

RESULTS

LncRNA GJA9-MYCBP and PVT1 were significantly upregulated in ALL samples compared with healthy ones. Similarly, mRNA levels of MYC were increased in ALL samples than control ones. Receiver operating characteristic curve analysis indicated a satisfactory diagnostic efficacy (p-value <.0001), suggesting that lncRNA GJA9-MYCBP and PVT1 may serve as a diagnostic biomarker for ALL. Linear regression analysis unveiled positive correlations between the expression level of MYC and lncRNA GJA9-MYCBP and PVT1 in ALL patients (p-values <.01).

CONCLUSIONS

In this study, we provided approval for the clinical diagnostic significance of lncRNA GJA9-MYCBP and PVT1that their upregulations may be a diagnostic biomarker for ALL.

Molecular Mechanisms of Tumorgenesis and Metastasis of Long Non-coding RNA (lncRNA) NEAT1 in Human Solid Tumors; An Update

The expression of the nuclear paraspeckle assembly transcript 1 (NEAT1), as a well-known long non-coding RNA (lncRNA), is often upregulated in varied types of cancers and associated with poor survival outcomes in patients suffering from tumors. NEAT1 promotes the tumors growth by influencing the various genes' expression profile that regulate various aspects of tumor cell behavior, in particular tumor growth, metastasis and drug resistance. This suggests that NEAT1 are capable of serving as a new diagnostic biomarker and target for therapeutic intervention. Through interrelation with enhancer of zeste homolog 2 (EZH2), NEAT1 acts as a scaffold RNA molecule, and thus regulating the expression EZH2-associated genes. Additionally, by perform as miRNA sponge, it constrains suppressing the interactions between miRNAs-mediated degradation of target mRNAs. In light of this, NEAT1 inhibition by small interfering RNA (siRNA) hampers tumorgenesis. We summarize recent findings about the expression, biological functions, and regulatory process of NEAT1 in human tumors. It specifically emphasizes the clinical significance of NEAT1 as a novel diagnostic biomarker and a promising therapeutic mark for many types of cancers.

RNASeq Analysis for Accurate Identification of Fusion Partners in Tumor Specific Translocations Detected by Standard FISH Probes in Hematologic Malignancies

Background

Fluorescence labeled DNA probes and in situ hybridization methods had shorter turn round time for results revolutionized their clinical application. Signals obtained from these probes are highly specific, yet they can produce fusion signals not necessarily representing fusion of actual genes due to other genes included in the probe design. In this study we evaluated discordance between cytogenetic, FISH and RNAseq results in 3 different patients with hematologic malignancies and illustrated the need to perform next generation sequencing (NGS) or RNASeq to accurately interpret FISH results.

Methods

Bone marrow or peripheral blood karyotypes and FISH were performed to detect recurring translocations associated with hematologic malignancies in clinical samples routinely referred to our clinical cytogenetics laboratory. When required, NGS was performed on DNA and RNA libraries to detect somatic alterations and gene fusions in some of these specimens. Discordance in results between these methods is further evaluated.

Results

For a patient with plasma cell leukemia standard FGFR3 / IGH dual fusion FISH assay detected fusion that was interpreted as FGFR3-positive leukemia, whereas NGS/RNASeq detected NSD2::IGH. For a pediatric acute lymphoblastic leukemia patient, a genetic diagnosis of PDGFRB-positive ALL was rendered because the PDGFRB break-apart probe detected clonal rearrangement, whereas NGS detected MEF2D::CSF1R. A MYC-positive B-prolymphocytic leukemia was rendered for another patient with a cytogenetically identified t(8;14) and MYC::IGH by FISH, whereas NGS detected a novel PVT1::RCOR1 not previously reported.

Conclusions

These are 3 cases in a series of several other concordant results, nevertheless, elucidate limitations when interpreting FISH results in clinical applications, particularly when other genes are included in probe design. In addition, when the observed FISH signals are atypical, this study illustrates the necessity to perform complementary laboratory assays, such as NGS and/or RNASeq, to accurately identify fusion genes in tumorigenic translocations.

Comprehensive analysis of candidate signatures of long non-coding RNA LINC01116 and related protein-coding genes in patients with hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is a long-term malignancy that causes high morbidities and mortalities worldwide. Notably, long non-coding RNAs (LncRNAs) have been identified as candidate targets for malignancy treatments.

METHODS

LncRNA LINC01116 and its Pearson-correlated genes (PCGs) were identified and analyzed in HCC patients. The diagnostic and prognostic value of the lncRNA was evaluated using data from The Cancer Genome Atlas (TCGA). Further, we explored the target drugs of LINC01116 for clinical application. Relationships between immune infiltration and PCGs, methylation and PCGs were explored. The diagnostic potentials were then validated by Oncomine cohorts.

RESULTS

LINC01116 and the PCG OLFML2B are differentially and highly expressed in tumor tissues (both P ≤ 0.050). We found that LINC01116, TMSB15A, PLAU, OLFML2B, and MRC2 have diagnostic potentials (all AUC ≥ 0.700, all P ≤ 0.050) while LINC01116 and TMSB15A have prognostic significance (both adjusted P ≤ 0.050). LINC01116 was enriched in the vascular endothelial growth factor (VEGF) receptor signaling pathway, mesenchyme morphogenesis, etc. After that, candidate target drugs with potential clinical significance were identified: Thiamine, Cromolyn, Rilmenidine, Chlorhexidine, Sulindac_sulfone, Chloropyrazine, and Meprylcaine. Analysis of immune infiltration revealed that MRC2, OLFML2B, PLAU, and TMSB15A are negatively associated with the purity but positively associated with the specific cell types (all P < 0.050). Analysis of promoter methylation demonstrated that MRC2, OLFML2B, and PLAU have differential and high methylation levels in primary tumors (all P < 0.050). Validation results of the differential expressions and diagnostic potential of OLFML2B (Oncomine) were consistent with those obtained in the TCGA cohort (P < 0.050, AUC > 0.700).

CONCLUSIONS

Differentially expressed LINC01116 could be a candidate diagnostic and an independent prognostic signature in HCC. Besides, its target drugs may work for HCC therapy via the VEGF receptor signaling pathway. Differentially expressed OLFML2B could be a diagnostic signature involved in HCC via immune infiltrates.

Parathyroid Carcinoma: Update on Pathogenesis and Therapy

Parathyroid carcinoma (PC) is a very rare endocrine cancer with aggressive behavior, a high metastatic potential, and a poor prognosis. Surgical resection of affected gland(s) and other involved structures is the elective therapy. Pre-operative and intra-operative differential diagnosis with benign parathyroid adenoma remains a challenge. The lack of a clear pre-operative diagnosis does not allow one, in many cases, to choose the correct surgical approach to malignant PC, increasing persistence, the recurrence rate, and the risk of metastases. An initial wrong diagnosis of parathyroid adenoma, with a minimally invasive parathyroidectomy, is associated with over 50% occurrence of metastases after surgery. Genetic testing could help in identifying patients at risk of congenital PC (i.e., CDC73 gene) and in driving the choice of neck surgery extension. Targeted effective treatments, other than surgery, for advanced and metastatic PC are needed. The pathogenesis of malignant parathyroid carcinogenesis is still largely unknown. In the last few years, advanced molecular techniques allowed researchers to identify various genetic abnormalities and epigenetic features characterizing PC, which could be crucial for selecting molecular targets and developing novel targeted therapeutic agents. We reviewed current findings in PC genetics, epigenetics, and proteomics and state-of-the-art therapies.

From cue to meaning: The involvement of POLD1 gene in DNA replication, repair and aging

Aging is an extremely complex biological process. Aging, cancer and inflammation represent a trinity, object of many interesting researches. The accumulation of DNA damage and its consequences progressively interfere with cellular function and increase susceptibility to developing aging condition. DNA Polymerase delta (Pol δ), encoded by POLD1 gene (MIM#174761) on 19q13.3, is well implicated in many steps of the replication program and repair. Thanks to its exonuclease and polymerase activities, the enzyme is involved in the regulation of the cell cycle, DNA synthesis, and DNA damage repair processes. Damaging variants within the exonuclease domain predispose to cancers, while those occurring in the polymerase active site cause the autosomal dominant Progeroid Syndrome called MDPL, Mandibular hypoplasia, Deafness and Progeroid features with concomitant Lipodystrophy Since DNA damage represents the main cause of ageing and age-related pathologies, an overview of critical Pol δ activities will allow to better understand the associations between DNA damage and nearly every aspect of the ageing process, helping the researchers to counteract all the ageing-pathologies at the same time.

Tumor-associated nonmyelinating Schwann cell-expressed PVT1 promotes pancreatic cancer kynurenine pathway and tumor immune exclusion

One of the major obstacles to treating pancreatic ductal adenocarcinoma (PDAC) is its immunoresistant microenvironment. The functional importance and molecular mechanisms of Schwann cells in PDAC remains largely elusive. We characterized the gene signature of tumor-associated nonmyelinating Schwann cells (TASc) in PDAC and indicated that the abundance of TASc was correlated with immune suppressive tumor microenvironment and the unfavorable outcome of patients with PDAC. Depletion of pancreatic-specific TASc promoted the tumorigenesis of PDAC tumors. TASc-expressed long noncoding RNA (lncRNA) plasmacytoma variant translocation 1 (PVT1) was triggered by the tumor cell-produced interleukin-6. Mechanistically, PVT1 modulated RAF proto-oncogene serine/threonine protein kinase-mediated phosphorylation of tryptophan 2,3-dioxygenase in TASc, facilitating its enzymatic activities in catalysis of tryptophan to kynurenine. Depletion of TASc-expressed PVT1 suppressed PDAC tumor growth. Furthermore, depletion of TASc using a small-molecule inhibitor effectively sensitized PDAC to immunotherapy, signifying the important roles of TASc in PDAC immune resistance.

Aberrantly expressed long noncoding RNAs as potential prognostic biomarkers in newly diagnosed multiple myeloma: A systemic review and meta-analysis

BACKGROUND

Numerous studies have manifested long noncoding RNAs (lncRNAs) as biomarkers to determine the prognosis of multiple myeloma (MM) patients. Nevertheless, the prognostic role of lncRNAs in MM is still ambiguous. Herein, we performed a meta-analysis to evaluate the predictive value of aberrantly expressed lncRNAs in MM.

METHODS

A systemic literature search was performed in PubMed, EMBASE, Cochrane, and Web of Science databases until October 9, 2021, and the protocol was registered in the PROSPERO database (CRD42021284364). Our study extracted the hazard ratios (HRs) and 95% confidence intervals (CIs) of overall survival (OS), progression-free survival (PFS), or event-free survival (EFS). Begg's and Egger's tests were employed to correct publication bias.

RESULT

Twenty-six individual studies containing 3501 MM patients were enrolled in this study. The results showed that aberrant expression of lncRNAs was associated with poor OS and PFS of MM patients. The pooled HRs for univariate OS and PFS were 1.48 (95% CI = 1.17-1.88, p < 0.001) and 1.30 (95% CI = 1.18-1.43, p < 0.001), respectively, whereas the pooled HRs for multivariate OS and PFS were 1.50 (95% CI = 1.16-1.95, p < 0.001) and 1.59 (95% CI = 1.22-2.07, p < 0.001), respectively. Subgroup analysis suggested that MALAT1, TCF7, NEAT1, and PVT1 upregulation were associated with poor OS (p < 0.05), PVT1, and TCF7 upregulation were implicated with worse PFS (p < 0.05), while only TCF7 overexpression was correlated with reduced EFS (p < 0.05). Moreover, the contour-enhanced funnel plot demonstrated the reliability of our current conclusion, which was not affected by publication bias.

CONCLUSION

Aberrantly expressed particular lncRNAs are critical prognostic indicators in long-term survival as well as promising biomarkers in progression-free status. However, different cutoff values and dissimilar methods to assess lncRNA expression among studies may lead to heterogeneity.

Lnc-SELPLG-2:1 enhanced osteosarcoma oncogenesis via hsa-miR-10a-5p and the BTRC cascade

BACKGROUND

To investigate the potential role of Long Non-coding RNAs (lncRNAs) in the progression of osteosarcoma.

METHODS

The candidate lncRNAs were screened with RNA-seq and confirmed with quantitative real-time PCR. Using MTS, transwell assay, and flow cytometric analysis, the effects of overexpressed lnc-SELPLG-2:1 on cell functions were determined. Immunohistochemical staining, fluorescence in situ hybridization, and luciferase reporter assay were used to evaluate the potential mechanism of lnc-SELPLG-2:1 in vivo and in vitro using a tumor model. Moreover, the effects of overexpression of hsa-miR-10a-5p on the functions of SaOS2 cells were determined using functional cell analysis. A response test was used to confirm the mechanism by which lnc-SELPLG-2:1 sponge hsa-miR-10a-5p promotes the expression of BTRC to regulate osteosarcoma.

RESULTS

Lnc-SELPLG-2:1 was highly expressed in osteosarcoma compared to normal cells and bone and marrow samples. Inhibition of lnc-SELPLG-2:1 accelerated cell apoptosis and suppressed cell proliferation, migration, and invasion, whereas lnc-SELPLG-2:1 overexpression had the opposite effect. Moreover, inhibiting lnc-SELPLG-2:1 in an in vivo model decreased tumor size and suppressed the expression of cell migration-related proteins. The prediction, dual luciferase assay, and response test results indicated that hsa-miR-10-5p and BTRC were involved in the lnc-SELPLG-2:1 cascade. Unlike lnc-SELPLG-2:1, hsa-hsa-miR-10a-5p had opposite expression and function. Competitive binding of lnc-SELPLG-2:1 to hsa-hsa-miR-10a-5p prevented BTRC from miRNA-mediated degradation, thereby activating the expression of VIM, MMP9, and MMP2, promoting osteosarcoma cell proliferation, migration, and invasion, and inhibiting apoptosis.

CONCLUSION

Lnc-SELPLG-2:1 is an oncogenesis activator in osteosarcoma, and its functions are performed via hsa-miR-10a-5p /BTRC cascade.

Enhancer RNA (eRNA) in Human Diseases

Enhancer RNAs (eRNAs), a class of non-coding RNAs (ncRNAs) transcribed from enhancer regions, serve as a type of critical regulatory element in gene expression. There is increasing evidence demonstrating that the aberrant expression of eRNAs can be broadly detected in various human diseases. Some studies also revealed the potential clinical utility of eRNAs in these diseases. In this review, we summarized the recent studies regarding the pathological mechanisms of eRNAs as well as their potential utility across human diseases, including cancers, neurodegenerative disorders, cardiovascular diseases and metabolic diseases. It could help us to understand how eRNAs are engaged in the processes of diseases and to obtain better insight of eRNAs in diagnosis, prognosis or therapy. The studies we reviewed here indicate the enormous therapeutic potency of eRNAs across human diseases.

Small hairpin inhibitory RNA delivery in the metanephric organ culture identifies long noncoding RNA Pvt1 as a modulator of cyst growth

Autosomal dominant polycystic kidney disease (ADPKD) is a monogenic disorder characterized by the formation of kidney cysts that originate from the epithelial tubules of the nephron and primarily results from mutations in polycystin-1 (PKD1) and polycystin-2 (PKD2). The metanephric organ culture (MOC) is an ex vivo system in which explanted embryonic kidneys undergo tubular differentiation and kidney development. MOC has been previously used to study polycystic kidney disease as treatment with 8-bromo-cAMP induces the formation of kidney cysts. However, the inefficiency of manipulating gene expression in MOC has limited its utility for identifying genes and pathways that are involved in cystogenesis. Here, we used a lentivirus and three serotypes of self-complementary adeno-associated viral (scAAV) plasmids that express green fluorescent protein and found that scAAV serotype D/J transduces the epithelial compartment of MOC at an efficiency of 68%. We used scAAV/DJ to deliver shRNA to knockdown Pvt1, a long noncoding RNA, which was upregulated in kidneys from Pkd1 and Pkd2 mutant mice and humans with ADPKD. shRNA delivery by scAAV/DJ downregulated expression of Pvt1 by 45% and reduced the cyst index by 53% in wild-type MOCs and 32% in Pkd1-null MOCs. Knockdown of Pvt1 decreased the level of c-MYC protein by 60% without affecting Myc mRNA, indicating that Pvt1 regulation of c-MYC was posttranscriptional. These results identify Pvt1 as a long noncoding RNA that modulates cyst progression in MOC.NEW & NOTEWORTHY This study identified scAAV/DJ as effective in transducing epithelial cells of the metanephric organ culture (MOC). We used scAAV/DJ shRNA to knockdown Pvt1 in cystic MOCs derived from Pkd1-null embryos. Downregulation of Pvt1 reduced cyst growth and decreased levels of c-MYC protein. These data suggest that suppression of Pvt1 activity in autosomal dominant polycystic kidney disease might reduce cyst growth.

Circular RNA (circ)_0129047 upregulates bone morphogenetic protein receptor type 2 expression to inhibit lung adenocarcinoma progression by sponging microRNA (miR)-1206

Circular RNAs (circRNAs) play significant roles in the tumorigenesis and progression of various cancers, including lung adenocarcinoma (LAC). However, their underlying biological functions in LAC remain unclear. Here, we investigated the tumor suppressor role of the newly identified circRNA, circ_0129047, in LAC tumorigenesis and progression. The expression levels of circ_0129047, microRNA (miR)-1206, and bone morphogenetic protein receptor type 2 (BMPR2) mRNA in LAC cells and tissues were monitored using reverse transcription-quantitative polymerase chain reaction. Dual-luciferase reporter, RNA immunoprecipitation, and RNA pull-down assays were used to confirm the targeting relationships among circ_0129047, miR-1206, and BMPR2 mRNA. Functional experiments for A549 and PC9 cells were performed using cell counting kit-8, bromodeoxyuridine enzyme-linked immunosorbent, caspase-3 activity, cell adhesion, wound healing, and transwell assays. Circ_0129047 expression levels were reduced in LAC cells and tissues. Mechanistically, we discovered that circ_0129047 could sponge miR-1206, and miR-1206 could directly target BMPR2. In addition, circ_0129047 or BMPR2 knockdown facilitated the viability, proliferation, adhesion, migration, and invasion, while inhibiting the apoptosis of LAC cells. Furthermore, the inhibitory effects of circ_0129047 or BMPR2 overexpression on the malignant phenotype of LAC cells could be reversed by the overexpression of miR-1206. In conclusion, circ _0129047 was found to play a tumor suppressive role in LAC progression; it upregulated BMPR2 expression to inhibit LAC progression by sponging miR-1206.

Abbreviations: non-small cell lung cancer (NSCLC); small cell lung cancer (SCLC); lung adenocarcinoma (LAC); Circular RNA (circRNA); MicroRNA (miRNA); bone morphogenetic protein (BMP); squamous cell lung cancer (SCC); RNA immunoprecipitation (RIP)

An innovative systematic approach introduced the involved lncRNA-miR-mRNA network in cell cycle and proliferation after conventional treatments in breast cancer patients

INTRODUCTION

The present study aimed to explore the involved lncRNA-miRNA-mRNA network in the cell cycle and proliferation after conventional treatments in Luminal A breast cancer patients.

METHODS

The candidate miRNAs (miRs), lncRNAs, and mRNAs were first taken from the Gene Expression Omnibus and TCGA databases. The lncRNA-miR-mRNA network was then constructed using the high-throughput sequencing data. The expression levels of selected targets were measured in the breast cancer and healthy samples by the Real-Time PCR technique and compared with the clinical outcomes by the Kaplan-Meier method.

RESULTS

Our analysis revealed a group of differentially expressed 3 lncRNAs, 9 miRs, and 14 mRNAs in breast cancer patients. A significant expression decrease of the selected tumor suppressor lncRNAs, miRs, and genes and a substantial expression increase of the selected onco-lncRNAs, oncomiRs, and oncogenes were obtained in the patients compared to the healthy group. The plasma levels of the lncRNAs, miRs, and mRNAs were more significant after the operation, chemotherapy, and radiotherapy than the pre-treatment. The Kaplan-Meier analysis indicated that the patients with a high expression of miR-21, miR-20b, IGF1R, and E2F2 and a low expression of miR-125a, PDCD4, and PTEN had exhibited a shorter overall survival rate.

CONCLUSION

Our results suggested that the underlying mechanisms of the lncRNA, miRs, and mRNAs and relevant signaling pathways may be considered predictive and therapeutic targets for breast cancer.

Long noncoding RNA PVT1 promotes chondrocyte extracellular matrix degradation by acting as a sponge for miR-140 in IL-1β-stimulated chondrocytes

Background

Osteoarthritis (OA) is a common degenerative joint disease, and chondrocyte extracellular matrix (ECM) degradation is one vital pathological feature of OA. Long noncoding RNA (lncRNA), a new kind of gene regulator, plays an important role in pathogenesis of many diseases like OA. Recent studies have confirmed that lncRNA plasmacytoma variant translocation 1 (PVT1) expression was upregulated in OA patients; however, its effect on ECM degradation remained unknown.

Methods

Cartilage tissue samples were obtained from 6 OA patients admitted in Guangdong Second Traditional Chinese Medicine Hospital. Chondrocytes were isolated and cultured from the collected cartilage tissue. Plasmid construction, RNA interference, cell transfection, fluorescence in situ hybridization (FISH), and pull-down assay were carried out during the research.

Results

In this study, PVT1 expression was significantly increased in chondrocytes stimulated by interleukin-1β (IL-1β). In addition, inhibition of PVT1 significantly downregulated the increased expressions of ADAM metallopeptidase with thrombospondin type 1 motif-5 (ADAMTS-5) and matrix metalloproteinase-13 (MMP-13) induced by IL-1β. Further investigation revealed that PVT1 was an endogenous sponge RNA, which directly bound to miR-140 and inhibited miR-140 expression.

Conclusion

To sum up, this study showed that PVT1 promoted expressions of ADAMTS-5 and MMP-13 as a competing endogenous RNA (ceRNA) of miR-140 in OA, which eventually led to aggravation of ECM degradation, thus providing a new and promising strategy for the treatment of OA.

Role and Mechanism of lncRNA-pvt1 in the Pathogenesis of Acute Lymphoblastic Leukemia in Children

Objective

To investigate the role and mechanism of lncRNA-pvt1 in the pathogenesis of childhood acute lymphoblastic leukemia (ALL).

Methods

The expression of lncRNA-pvt1 in bone marrow tissues of ALL patients after initial diagnosis and complete remission was detected by RT-PCR to explore its possible involvement in the pathogenesis of ALL. The proliferation and apoptosis of Jurkat cells transfected with lncRNA-pvt1 were observed by MTT and flow cytometry.

Results

lncRNA-pvt1 expression was upregulated in bone marrow of ALL patients. Knockdown of lncRNA-pvt1 inhibited Jurkat cell proliferation and increased its apoptosis rate.

Conclusion

Silencing lncRNA-pvt1 expression can inhibit the development of ALL.

Downregulation of lncRNA PVT1 inhibits proliferation and migration of mesothelioma cells by targeting FOXM1

Malignant mesothelioma is a highly aggressive tumor, and an effective strategy for its treatment is not yet available. Long non-coding RNAs (lncRNAs) have been reported to be associated with various biological processes, including the regulation of gene expression of cancer-related pathways. Among various lncRNAs, plasmacytoma variant translocation 1 (PVT1) acts as a tumor promoter in several human cancers, but its mechanism of action has not yet been elucidated. Increased PVT1 expression was identified in ACC-MESO-1, ACC-MESO-4, CRL-5915, and CRL-5946 mesothelioma cell lines. PVT1 expression was investigated in mesothelioma cell lines by reverse transcription-quantitative polymerase chain reaction and its functional analysis by cell proliferation, cell cycle, cell migration, and cell invasion assays, as well as western blot analysis of downstream target genes. Knockdown of PVT1 expression in these cell lines by small interfering RNA transfection resulted in decreased cell proliferation and migration and increased the proportion of cells in the G2/M phase. The results of reverse transcription-quantitative polymerase chain reaction analysis revealed that PVT1 knockdown in mesothelioma cell lines caused the downregulation of Forkhead box M1 (FOXM1) expression, while the results of western blot analysis revealed that this knockdown reduced FOXM1 expression at the protein level. In addition, combined knockdown of PVT1 and FOXM1 decreased the proliferation of mesothelioma cell lines. In conclusion, PVT1 and FOXM1 were involved in the proliferation of cancer cells. Therefore, PVT1-FOXM1 pathways may be considered as candidate targets for the treatment of malignant mesothelioma.

Identification and Functional Analysis of lncRNAs Responsive to Hypoxia in Eospalax fontanierii

Subterranean rodents could maintain their normal activities in hypoxic environments underground. Eospalax fontanierii, as one kind of subterranean rodent found in China can survive very low oxygen concentration in labs. It has been demonstrated that long non-coding RNAs (lncRNAs) have important roles in gene expression regulations at different levels and some lncRNAs were found as hypoxia-regulated lncRNAs in cancers. We predicted thousands of lncRNAs in the liver and heart tissues by analyzing RNA-Seq data in Eospalax fontanierii. Those lncRNAs often have shorter lengths, lower expression levels, and lower GC contents than mRNAs. Majors of lncRNAs have expression peaks in hypoxia conditions. We found 1128 DE-lncRNAs (differential expressed lncRNAs) responding to hypoxia. To search the miRNA regulation network for lncRNAs, we predicted 471 and 92 DE-lncRNAs acting as potential miRNA target and target mimics, respectively. We also predicted the functions of DE-lncRNAs based on the co-expression networks of lncRNA-mRNA. The DE-lncRNAs participated in the functions of biological regulation, signaling, development, oxoacid metabolic process, lipid metabolic/biosynthetic process, and catalytic activity. As the first study of lncRNAs in Eospalax fontanierii, our results show that lncRNAs are popular in transcriptome widely and can participate in multiple biological processes in hypoxia responses.

A mechanistic view of long noncoding RNAs in cancer

Long noncoding RNAs (lncRNAs) have emerged as important modulators of a wide range of biological processes in normal and disease states. In particular, lncRNAs have garnered significant interest as novel players in the molecular pathology of cancer, spurring efforts to define the functions, and elucidate the mechanisms through which cancer‐associated lncRNAs operate. In this review, we discuss the prevalent mechanisms employed by lncRNAs, with a critical assessment of the methodologies used to determine each molecular function. We survey the abilities of cancer‐associated lncRNAs to enact diverse trans functions throughout the nucleus and in the cytoplasm and examine the local roles of cis‐acting lncRNAs in modulating the expression of neighboring genes. In linking lncRNA functions and mechanisms to their roles in cancer biology, we contend that a detailed molecular understanding of lncRNA functionality is key to elucidating their contributions to tumorigenesis and to unlocking their therapeutic potential.

This article is categorized under:

Regulatory RNAs/RNAi/Riboswitches > Regulatory RNAs

RNA in Disease and Development > RNA in Disease

The role of noncoding RNAs in pituitary adenoma

Pituitary adenomas (PAs) are common cranial tumors that affect the quality of life in patients. Early detection of PA is beneficial for avoiding clinical complications of this disease and increasing the quality of life. Noncoding RNAs, including long noncoding RNA, miRNA and circRNA, regulate protein expression, mostly by inhibiting the translation process. Studies have shown that dysregulation of noncoding RNAs is associated with PA. Hence understanding the expression pattern of noncoding RNAs can be considered a promising method for developing biomarkers. This article reviews data on the expression pattern of dysregulated noncoding RNAs involved in PA. Possible molecular mechanisms by which the dysregulated noncoding RNA could possibly induce PA are also described.

The Role of Non-Coding RNAs in the Regulation of the Proto-Oncogene MYC in Different Types of Cancer

Alterations in the expression level of the MYC gene are often found in the cells of various malignant tumors. Overexpressed MYC has been shown to stimulate the main processes of oncogenesis: uncontrolled growth, unlimited cell divisions, avoidance of apoptosis and immune response, changes in cellular metabolism, genomic instability, metastasis, and angiogenesis. Thus, controlling the expression of MYC is considered as an approach for targeted cancer treatment. Since c-Myc is also a crucial regulator of many cellular processes in healthy cells, it is necessary to find ways for selective regulation of MYC expression in tumor cells. Many recent studies have demonstrated that non-coding RNAs play an important role in the regulation of the transcription and translation of this gene and some RNAs directly interact with the c-Myc protein, affecting its stability. In this review, we summarize current data on the regulation of MYC by various non-coding RNAs that can potentially be targeted in specific tumor types.

A positive feedback regulatory loop involving the lncRNA PVT1 and HIF-1α in pancreatic cancer

Extreme hypoxia is among the most prominent pathogenic features of pancreatic cancer (PC). Both the long non-coding RNA (lncRNA) plasmacytoma variant translocation 1 (PVT1) and hypoxic inducible factor-1α (HIF-1α) are highly expressed in PC patients and play a crucial role in disease progression. Reciprocal regulation involving PVT1 and HIF-1α in PC, however, is poorly understood. Here, we report that PVT1 binds to the HIF-1α promoter and activates its transcription. In addition, we found that PVT1 could bind to HIF-1α and increases HIF-1α post-translationally. Our findings suggest that the PVT1‒HIF-1α positive feedback loop is a potential therapeutic target in the treatment of PC.

Knockdown of plasmacytoma variant translocation 1 (PVT1) inhibits high glucose-induced proliferation and renal fibrosis in HRMCs by regulating miR-23b-3p/early growth response factor 1 (EGR1)

Long noncoding RNAs (lncRNAs) have been reported to play critical role in the development of diabetic nephropathy (DN). However, the effects and mechanism of plasmacytoma variant translocation 1 (PVT1) remain poorly understood. The expression of PVT1, miR-23b-3p, early growth response factor 1 (EGR1), Fibronectin (FN), Collagen IV (Col IV), alpha smooth muscle actin (α-SMA), E-cadherin, and vimentin, transforming growth factor (TGF)-β1 was examined by quantitative real-time polymerase chain reaction (qRT-PCR). Cell proliferation was assessed by Cell Counting-8 (CCK-8) assay. Western blot assay was conducted to measure the protein levels of FN, Col IV, E-cadherin, α-SMA, vimentin, TGF-β1, and EGR1. The interaction between miR-23b-3p and PVT1 or EGR1 was predicted by starBase or TargetScan and confirmed by the dual luciferase reporter assay. The oxidative stress factors were analyzed by corresponding kits. We found that the expression of PVT1 and EGR1 was increased and miR-23b-3p was decreased in serum samples of DN patients and HG-induced HRMCs. Knockdown of PVT1 significantly inhibited HG-induced proliferation, extracellular matrix (ECM) accumulation, epithelial-mesenchymal transition (EMT), and oxidative stress in HRMCs, while these effects were abated by inhibiting miR-23b-3p. In addition, EGR1 was confirmed as downstream target of miR-23b-3p and miR-23b-3p could specially bind to PVT1. Besides, downregulation of PVT1 inhibited the progression of DN partially via upregulating miR-23b-3p and downregulating EGR1. In conclusion, our results suggested that PVT1 knockdown suppressed DN progression though functioning as ceRNA of miR-23b-3p to regulate EGR1 expression in vitro, providing potential value for the treatment of DN.

Lentinan Attenuated the PM2.5 Exposure-Induced Inflammatory Response, Epithelial-Mesenchymal Transition and Migration by Inhibiting the PVT1/miR-199a-5p/caveolin1 Pathway in Lung Cancer

PM2.5 plays an important role in the physiological and pathological progression of lung cancer. Lentinan exerts antitumor activity in many kinds of human cancers. Plasmacytoma variant translocation 1 (PVT1) exerts antitumor activity in many kinds of human cancers. However, the role and underlying molecular mechanism of PVT1 in the role of lentinan in PM2.5-exposed lung cancer are still largely unknown. Our study confirmed that PM2.5 exposure induced the production of inflammatory factors, epithelial-mesenchymal transition (EMT) and migration of lung cancer cells. Lentinan exerted antitumor effects by inhibiting the production of inflammatory factors, EMT, and migration of lung cancer cells. Lentinan suppressed PM2.5 exposure-induced cellular progression by inhibiting the PM2.5 exposure-induced elevation of PVT1 expression. PVT1 absorbed miR-199a, and miR-199a inhibited caveolin1 expression and thus formed the PVT1/miR-199a/caveolin1 signaling pathway in lung cancer cells. Our study revealed that silencing of the PVT1/miR-199a/caveolin1 signaling pathway affected the role of lentinan in PM2.5-exposed lung cancer cells. Thus, this study first investigated the role of lentinan in PM2.5-exposed lung cancer cells and further displayed the underlying molecular mechanism, providing a potential treatment for PM2.5-exposed lung cancer.

Roles of Non-Coding RNAs in Cervical Cancer Metastasis

Metastasis remains to be a huge challenge in cancer therapy. The mechanism underlying cervical cancer metastasis is not well understood and needs to be elucidated. Recent studies have highlighted the diverse roles of non-coding RNAs in cancer progression and metastasis. Increasing numbers of miRNAs, lncRNAs and circRNAs are found to be dysregulated in cervical cancer, associated with metastasis. They have been shown to regulate metastasis through regulating metastasis-related genes, epithelial-mesenchymal transition, signaling pathways and interactions with tumor microenvironment. Moreover, miRNAs can interact with lncRNAs and circRNAs respectively during this complex process. Herein, we review literatures up to date involving non-coding RNAs in cervical cancer metastasis, mainly focus on the underlying mechanisms and highlight the interaction network between miRNAs and lncRNAs, as well as circRNAs. Finally, we discuss the therapeutic prospects.

Immunotherapy Targeting Myeloid-Derived Suppressor Cells (MDSCs) in Tumor Microenvironment

Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of immature myeloid cells that accumulate in tumor-bearing hosts to reduce T cells activity and promote tumor immune escape in the tumor microenvironment (TME). The immune system in the TME can be stimulated to elicit an anti-tumor immune response through immunotherapy. The main theory of immunotherapy resides on the plasticity of the immune system and its capacity to be re-educated into a potent anti-tumor response. Thus, MDSCs within the TME became one of the major targets to improve the efficacy of tumor immunotherapy, and therapeutic strategies for tumor MDSCs were developed in the last few years. In the article, we analyzed the function of tumor MDSCs and the regulatory mechanisms of agents targeting MDSCs in tumor immunotherapy, and reviewed their therapeutic effects in MDSCs within the TME. Those data focused on discussing how to promote the differentiation and maturation of MDSCs, reduce the accumulation and expansion of MDSCs, and inhibit the function, migration and recruitment of MDSCs, further preventing the growth, invasion and metastasis of tumor. Those investigations may provide new directions for cancer therapy.

The Functions and Unique Features of LncRNAs in Cancer Development and Tumorigenesis

Over the past decades, research on cancer biology has focused on the involvement of protein-coding genes in cancer development. Long noncoding RNAs (lncRNAs), which are transcripts longer than 200 nucleotides that lack protein-coding potential, are an important class of RNA molecules that are involved in a variety of biological functions. Although the functions of a majority of lncRNAs have yet to be clarified, some lncRNAs have been shown to be associated with human diseases such as cancer. LncRNAs have been shown to contribute to many important cancer phenotypes through their interactions with other cellular macromolecules including DNA, protein and RNA. Here we describe the literature regarding the biogenesis and features of lncRNAs. We also present an overview of the current knowledge regarding the roles of lncRNAs in cancer from the view of various aspects of cellular homeostasis, including proliferation, survival, migration and genomic stability. Furthermore, we discuss the methodologies used to identify the function of lncRNAs in cancer development and tumorigenesis. Better understanding of the molecular mechanisms involving lncRNA functions in cancer is critical for the development of diagnostic and therapeutic strategies against tumorigenesis.

LncRNA PVT1 Acts as a Tumor Promoter in Thyroid Cancer and Promotes Tumor Progression by Mediating miR-423-5p-PAK3

Introduction

Thyroid cancer (TC) is an endocrine tumor whose risk of onset has been rising, so the deep understanding of its molecular mechanism helps formulate new treatment strategies.

Methods

This paper was aimed at exploring the regulatory mechanism of long non-coding RNA (LncRNA) plasmacytoma variant translocation 1 (PVT1) in TC. The expression of PVT1, miR-423-5p and p21-activated kinase 3 (PAK3) in TC tissues and cell lines was detected by real-time PCR. PAK3 levels were detected by Western blot. Regulatory relationships between target genes and the proliferation, invasion and apoptosis of cells and genes were analyzed.

Results

PVT1 and PAK3 upregulated while miR-423-5p downregulated in the tissues and cell lines. PVT1 downregulation inhibited TC cells from malignantly proliferating and invading, and promoted their apoptosis. PVT1 specifically regulated miR-423-5p, and its overexpression could weaken the anti-tumor effect of this miR on TC cells. In addition, miR-423-5p directly targeted PAK3, and knocking down its expression could weaken the inhibitory effect of PAK3 downregulation on TC progression. Besides, PVT1 acted as a competitive endogenous RNA to sponge this miR and thus regulate PAK3 expression.

Discussion

In conclusion, PVT1 can mediate the molecular mechanism of the miR-423-5p-PAK3 axis regulatory network on regulating TC, so it is a new direction of treating the disease.

Effect of LncPVT1/miR-20a-5p on Lipid Metabolism and Insulin Resistance in NAFLD

PURPOSE

Nonalcoholic fatty liver disease (NAFLD) is closely related to lipid metabolism and insulin resistance. The current research mainly attempted to verify the clinical value of LncRNA plasmacytoma variant translocation 1 (PVT1), and whether microRNA regulates lipid metabolism and insulin resistance to participate in NAFLD.

PATIENTS AND METHODS

81 patients with NAFLD and 78 healthy individuals were enrolled in this study. In addition, C57BL/6 mice were fed a high-fat diet to establish NAFLD model in vivo. Serum PVT1 and miR-20a-5p expression in NAFLD patients and mice were assessed by RT-qPCR. ROC curves determine the diagnostic value of PVT1 and miR-20a-5p. NAFLD mice were subjected to IPGTT to detect changes in insulin sensitivity, and the common indicators of lipid metabolism and insulin resistance were also evaluated. Dual-luciferase reporter assay verified the regulation mechanism of PVT1 and miR-20a-5p.

RESULTS

PVT1 was upregulated in NAFLD patients and mice, while miR-20a-5p was decreased. Their expression trends were similar in patients with HOMA-IR ≥2.5. What's more, miR-20a-5p, FBG, ALT, and HOMA-IR were independently correlated with PVT1. And PVT1 and miR-20a-5p show high clinical diagnostic value. Bodyweight, insulin sensitivity, lipid metabolism inductors were increased in NAFLD mice, but these increases were attenuated by PVT1 elimination. Finally, miR-20a-5p might function as the possible miRNA target of PVT1 via the binding sites at 3'-UTR and negatively regulated by it.

CONCLUSION

PVT1 and miR-20a-5p are potential clinical biomarkers of NAFLD, and PVT1 promotes the occurrence of NAFLD by regulating insulin sensitivity and lipid metabolism, which may be achieved by targeting miR-20a-5p.

Gene regulation by long non-coding RNAs and its biological functions

Evidence accumulated over the past decade shows that long non-coding RNAs (lncRNAs) are widely expressed and have key roles in gene regulation. Recent studies have begun to unravel how the biogenesis of lncRNAs is distinct from that of mRNAs and is linked with their specific subcellular localizations and functions. Depending on their localization and their specific interactions with DNA, RNA and proteins, lncRNAs can modulate chromatin function, regulate the assembly and function of membraneless nuclear bodies, alter the stability and translation of cytoplasmic mRNAs and interfere with signalling pathways. Many of these functions ultimately affect gene expression in diverse biological and physiopathological contexts, such as in neuronal disorders, immune responses and cancer. Tissue-specific and condition-specific expression patterns suggest that lncRNAs are potential biomarkers and provide a rationale to target them clinically. In this Review, we discuss the mechanisms of lncRNA biogenesis, localization and functions in transcriptional, post-transcriptional and other modes of gene regulation, and their potential therapeutic applications.

Hepatitis C virus associated hepatocellular carcinoma

Liver cancer is a global problem and hepatocellular carcinoma (HCC) accounts for about 85% of this cancer. In the USA, etiologies and risk factors for HCC include chronic hepatitis C virus (HCV) infection, diabetes, non-alcoholic steatohepatitis (NASH), obesity, excessive alcohol drinking, exposure to tobacco smoke, and genetic factors. Chronic HCV infection appears to be associated with about 30% of HCC. Chronic HCV infection induces multistep changes in liver, involving metabolic disorders, steatosis, cirrhosis and HCC. Liver carcinogenesis requires initiation of neoplastic clones, and progression to clinically diagnose malignancy. Tumor progression associates with profound exhaustion of tumor-antigen-specific CD8⁺T cells, and accumulation of PD-1^hi CD8⁺T cells and Tregs. In this chapter, we provide a brief description of HCV and environmental/genetic factors, immune regulation, and highlight mechanisms of HCV associated HCC. We also underscore HCV treatment and recent paradigm of HCC progression, highlighted the current treatment and potential future therapeutic opportunities.

LncRNAs in Cancer: From garbage to Junk

Sequencing-based transcriptomics has significantly redefined the concept of genome complexity, leading to the identification of thousands of lncRNA genes identification of thousands of lncRNA genes whose products possess transcriptional and/or post-transcriptional regulatory functions that help to shape cell functionality and fate. Indeed, it is well-established now that lncRNAs play a key role in the regulation of gene expression through epigenetic and posttranscriptional mechanims. The rapid increase of studies reporting lncRNAs alteration in cancers has also highlighted their relevance for tumorigenesis. Herein we describe the most prominent examples of well-established lncRNAs having oncogenic and/or tumor suppressive activity. We also discuss how technical advances have provided new therapeutic strategies based on their targeting, and also report the challenges towards their use in the clinical settings.

Knockdown of exosome‑mediated lnc‑PVT1 alleviates lipopolysaccharide‑induced osteoarthritis progression by mediating the HMGB1/TLR4/NF‑κB pathway via miR‑93‑5p

Osteoarthritis is a chronic degenerative joint disease. Long non‑coding RNA plasmacytoma variant translocation 1 (PVT1) is involved in the progression of osteoarthritis and exosomes serve a central role in intercellular communication. However, whether PVT1 can be mediated by exosomes in osteoarthritis has not been reported. Whole blood was drawn from osteoarthritis patients and healthy volunteers. Lipopolysaccharide (LPS) was used to stimulate human normal chondrocytes (C28/I2) to construct a cell damage model in vitro. Protein levels were examined via western blot analysis. eThe expression of PVT1, microRNA (miR)‑93‑5p and high mobility groupprotein B1 (HMGB1) was evaluated through reverse transcription‑quantitative PCR. Cell viability and apoptosis were determined through CCK‑8 or flow cytometric assay. Inflammatory cytokines were measured via ELISA. The relationship between PVT1 or HMGB1 and miR‑93‑5p was confirmed by dual‑luciferase reporter assay. PVT1, HMGB1 and exosomal PVT1 were upregulated while miR‑93‑5p was downregulated in osteoarthritis patient serum and LPS‑induced C28/I2 cells. Exosomes from osteoarthritis patient serum and LPS‑treated C28/I2 cells increased PVT1 expression in C28/I2 cells. PVT1 depletion reversed the decrease of viability and the increase of apoptosis, inflammation responses and collagen degradation of C28/I2 cells induced by LPS. PVT1 regulated HMGB1 expression via sponging miR‑93‑5p. miR‑93‑5p inhibition abolished PVT1 silencing‑mediated viability, apoptosis, inflammation responses and collagen degradation of LPS‑stimulated C28/I2 cells. HMGB1 increase overturned miR‑93‑5p upregulation‑mediated viability, apoptosis, inflammation responses and collagen degradation of LPS‑stimulated C28/I2 cells. Furthermore, PVT1 modulated the Toll‑like receptor 4/NF‑κB pathway through an miR‑93‑5p/HMGB1 axis. In summary, exosome‑mediated PVT1 regulated LPS‑induced osteoarthritis progression by modulating the HMGB1/TLR4/NF‑κB pathway via miR‑93‑5p, providing a new route for possible osteoarthritis treatment.

Crosstalk Between MYC and lncRNAs in Hematological Malignancies

The human genome project revealed the existence of many thousands of long non-coding RNAs (lncRNAs). These transcripts that are over 200 nucleotides long were soon recognized for their importance in regulating gene expression. However, their poor conservation among species and their still controversial annotation has limited their study to some extent. Moreover, a generally lower expression of lncRNAs as compared to protein coding genes and their enigmatic biochemical mechanisms have impeded progress in the understanding of their biological roles. It is, however, known that lncRNAs engage in various kinds of interactions and can form complexes with other RNAs, with genomic DNA or proteins rendering their functional regulatory network quite complex. It has emerged from recent studies that lncRNAs exert important roles in gene expression that affect many cellular processes underlying development, cellular differentiation, but also the pathogenesis of blood cancers like leukemia and lymphoma. A number of lncRNAs have been found to be regulated by several well-known transcription factors including Myelocytomatosis viral oncogene homolog (MYC). The c-MYC gene is known to be one of the most frequently deregulated oncogenes and a driver for many human cancers. The c-MYC gene is very frequently activated by chromosomal translocations in hematopoietic cancers most prominently in B- or T-cell lymphoma or leukemia and much is already known about its role as a DNA binding transcriptional regulator. Although the understanding of MYC's regulatory role controlling lncRNA expression and how MYC itself is controlled by lncRNA in blood cancers is still at the beginning, an intriguing picture emerges indicating that c-MYC may execute part of its oncogenic function through lncRNAs. Several studies have identified lncRNAs regulating c-MYC expression and c-MYC regulated lncRNAs in different blood cancers and have unveiled new mechanisms how these RNA molecules act. In this review, we give an overview of lncRNAs that have been recognized as critical in the context of activated c-MYC in leukemia and lymphoma, describe their mechanism of action and their effect on transcriptional reprogramming in cancer cells. Finally, we discuss possible ways how an interference with their molecular function could be exploited for new cancer therapies.

Tissue-based long non-coding RNAs "PVT1, TUG1 and MEG3" signature predicts Cisplatin resistance in ovarian Cancer

OBJECTIVES

The current study aimed to investigate the potentiality of three lncRNAs "Plasmacytoma variant translocation 1(lnc-PVT1), Taurine upregulated gene type 1(lnc-TUG1) and Maternally expressed gene 3 (lnc-MEG-3)", to predict Cisplatin resistance in ovarian cancer (OC), in addition, to access their prognostic significance.

METHODS

The expression level of lncRNAs were measured in 100 formalin-fixed paraffin-embedded tissue (FFET) samples of OC patients who were treated by Cisplatin-based chemotherapy using qPCR.

RESULTS

The results showed that lnc_PVT1 was significantly upregulated by 2.3 folds in Cisplatin resistant tissues, while, lnc-TUG1 and lnc-MEG3 were downregulated by 1.2 and 3 folds, respectively. In addition, the three lncRNAs exhibited high sensitivity and specificity in predicting chemo-resistance and they were negatively associated with OS and progression-free survival (p < 0.001).

CONCLUSION

The lnc-PVT1, lnc-TUG1, and lnc-MEG3 transcriptome signatures could be used for predicting resistance to Cisplatin in OC patients.

Huaier Restrains Cholangiocarcinoma Progression in vitro and in vivo Through Modulating lncRNA TP73-AS1 and Inducing Oxidative Stress

Purpose

Huaier, the fruiting body of Trametes robiniophila Murr, is a kind of traditional Chinese medicine. Recently, many studies have confirmed that Huaier has antitumor effects on various malignancies. Moreover, studies have demonstrated that long noncoding RNAs play an important regulatory role in the occurrence and progression of malignancies. Our present study was to explore whether Huaier has a potential antitumor effect in cholangiocarcinoma and reveal the relationship between lncRNAs and Huaier-induced tumor inhibition.

Methods

Microarray assay was performed to identify the candidate lncRNAs regulated by Huaier. Quantitative real-time PCR was applied to assess the effect of Huaier on TP73-AS1 expression. The effect of Huaier on the cell viability, proliferation, migration and invasion was evaluated by CCK-8, colony formation, wound healing and Transwell assays, respectively. The ratio of cell apoptosis was determined using AO/EB, Hoechst 33342 and flow cytometry. The effect of Huaier on oxidative stress was revealed using DCFH-DA, mito-SOX, JC-1 probes and Western blotting. In addition, the effect of Huaier on tumor growth and metastasis was explored using subcutaneous tumor model and lung metastatic tumor model in nude mice.

Results

In vitro, Huaier inhibited the proliferation, migration and invasion of cholangiocarcinoma cells by down-regulating TP73-AS1 and induced apoptosis through mitochondrial apoptotic pathway. In vivo, Huaier suppressed the growth and metastasis of cholangiocarcinoma by modulating the expression of proliferation and EMT-associated proteins.

Conclusion

Huaier could inhibit cell proliferation, invasion and metastasis by modulating the expression of TP73-AS1, meanwhile promote apoptosis of CCA cells through disturbing mitochondrial function, inducing oxidative stress and activating caspases in vitro. In addition, Huaier could suppress tumor growth and metastasis by regulating the expression of proliferation and EMT-related proteins. In the meantime, Huaier prolonged the survival of nude mice in lung metastatic model with acceptable drug safety.

Inherited Genetic Mutations and Polymorphisms in Malignant Mesothelioma: A Comprehensive Review

Malignant mesothelioma (MM) is mainly caused by air-born asbestos but genetic susceptibility is also suspected to be a risk factor. Recent studies suggest an increasing number of candidate genes that may predispose to MM besides the well-characterized BRCA1-associated protein-1 gene. The aim of this review is to summarize the most important studies on germline mutations for MM. A total of 860 publications were retrieved from Scopus, PubMed and Web of Science, of which 81 met the inclusion criteria and were consider for this review. More than 50% of the genes that are reported to predispose to MM are involved in DNA repair mechanisms, and the majority of them have a role in the homologous recombination pathway. Genetic alterations in tumor suppressor genes involved in chromatin, transcription and hypoxia regulation have also been described. Furthermore, we identified several single nucleotide polymorphisms (SNPs) that may promote MM tumorigenesis as a result of an asbestos-gene interaction, including SNPs in DNA repair, carcinogen detoxification and other genes previously associated with other malignancies. The identification of inherited mutations for MM and an understanding of the underlying pathways may allow early detection and prevention of malignancies in high-risk individuals and pave the way for targeted therapies.

LncRNA PVT1 promotes exosome secretion through YKT6, RAB7, and VAMP3 in pancreatic cancer

Pancreatic cancer (PC) is one of the deadliest cancers worldwide. Cancer cells secrete excessive numbers of exosomes that play essential roles in tumorigenesis. Long non-coding RNAs (lncRNAs) are essential non-coding RNAs for cancer progression. However, the role of lncRNA plasmacytoma variant translocation 1 (PVT1) in exosome secretion of PC remains to be comprehensively investigated. Thus, nanoparticle tracking analysis and transmission electron microscopy were performed to determine exosome secretion. Confocal microscopy, western blots, real-time PCR, immunofluorescence, pull-down and RNA immunoprecipitation assays, and rescue experiments were applied to investigate the mechanism underlying the role of PVT1 in exosome secretion. The results showed that PVT1 was upregulated in PC cells, along with increased levels of YKT6 v-SNARE homolog (YKT6), ras-related protein Rab-7 (RAB7), and vesicle-associated membrane protein 3 (VAMP3). Also, PVT1 promoted the transportation of multivesicular bodies (MVBs) towards the plasma membrane. In addition, PVT1 promoted the docking of MVBs by altering RAB7 expression and localization. Moreover, PVT1 promoted the fusion of MVBs with the plasma membrane through regulating YKT6 and VAMP3 colocalization and the palmitoylation of YKT6. Taken together, the results suggest that PVT1 promoted exosome secretion of PC cells and thus, can expand the understanding of PVT1 in tumor biology.

Evolution and structure of clinically relevant gene fusions in multiple myeloma

Multiple myeloma is a plasma cell blood cancer with frequent chromosomal translocations leading to gene fusions. To determine the clinical relevance of fusion events, we detect gene fusions from a cohort of 742 patients from the Multiple Myeloma Research Foundation CoMMpass Study. Patients with multiple clinic visits enable us to track tumor and fusion evolution, and cases with matching peripheral blood and bone marrow samples allow us to evaluate the concordance of fusion calls in patients with high tumor burden. We examine the joint upregulation of WHSC1 and FGFR3 in samples with t(4;14)-related fusions, and we illustrate a method for detecting fusions from single cell RNA-seq. We report fusions at MYC and a neighboring gene, PVT1, which are related to MYC translocations and associated with divergent progression-free survival patterns. Finally, we find that 4% of patients may be eligible for targeted fusion therapies, including three with an NTRK1 fusion.

Multiple myeloma is characterised by frequent gene fusions. Here, the authors use data from the Multiple Myeloma Research Foundation CoMMpass Study to further investigate fusion genes in this disease and their clinical relevance.

Reduce proliferation of human bone marrow cells from acute myeloblastic leukemia with minimally differentiation by blocking lncRNA PVT1

PURPOSE

Acute myeloblastic leukemia with minimally differentiation (AML-M0) is a subtype of acute leukemia with poor prognosis. The recent studies have shown that long non-coding RNAs (lncRNAs) play an important role in different cellular processes, such as cell cycle control and proliferation. Plasmacytoma variant translocation 1 (PVT1) is one of those lncRNAs that is significantly upregulated in AML. LncRNAs could be downregulated or blocked by locked nucleic acids (LNA) which are oligonucleotide strands.

METHODS

In this study, lncRNA PVT1 was blocked by antisense LNA GapmeRs in human bone marrow cancerous blast cells. Cells were transfected with PVT1 antisense LNA GapmeRs at 24, 48, and 72 h post-transfection. Quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) was accomplished to evaluate the PVT1 and c-Myc expression. Cell viability was evaluated by MTT assay, and apoptosis and necrosis were assessed by Annexin V/propidium iodide staining assay.

RESULTS

The results of this study indicated that the downregulation of PVT1 in blast cells could induce apoptosis, and necrosis and reduce cell viability. The expression of c-Myc was downregulated by blockage of PVT1 and it shows that the expression of these two genes are correlated.

CONCLUSION

The findings declare that inhibition of PVT1 could be a new target in the treatment of AML-M0 and help to approach more to treatments with fewer side effects.

Long noncoding RNAs in osteosarcoma via various signaling pathways

Osteosarcoma is one of the most commonly seen bone malignancies with high incidence rate in both children and adults. Although the regulatory network of osteosarcoma has been greatly concerned for years, the mechanisms regarding its oncogenesis and development are still not clear. Recent discoveries have revealed that long noncoding RNAs (lncRNAs) play a crucial role in the development, progression, and invasion of osteosarcoma. Deregulated expression of lncRNAs has been found to participate in the regulation of various signaling transduction pathways in osteosarcoma. This review summarized roles of lncRNAs in the pathogenesis, development, and potential therapeutic of osteosarcoma via different signaling pathways. For examples, MALAT1, CCAT2, FER1L4, LOXL1‐AS1, OIP5‐AS1, PVT1, DBH‐AS1, and AWPPH regulate PI3K/Akt signaling; AWPPH and BE503655 regulate Wnt/β‐catenin signaling; NKILA and XIST regulate NF‐κB signaling; MEG3 and SNHG12 regulate Notch signaling; FOXD2‐AS1 and LINK‐A regulate HIF‐1α signaling; GClnc1 and HOTAIR regulate P53 signaling; ZFAS1, H19, and MALAT1 regulate MAPK, Hedgehog and Rac1/JNK signaling, respectively.

A miRNA- and mRNA-seq-Based Feature Selection Approach for Kidney Cancer Biomakers

Microarray data sets have been used for predicting cancer biomarkers. Yet, replication of the prediction has not been fully satisfied. Recently, new data sets called deep sequencing data sets have been generated, with an advantage of less noise in computational analysis. In this study, we analyzed the kidney miRNA and mRNA sequence data sets for predicting cancer markers using 5 different statistical feature selection methods. In the results, we obtained 3 mRNA- and 27 miRNA-based cancer biomarkers to compare with the normal samples. In addition, we clustered the kidney cancer subtypes using a nonnegative matrix factorization method and obtained significant results of survival analysis from the 2 separate groups including miRNA-342 and its target eukaryotic translation initiation factor 5A (EIF5A).

The Complex Network between MYC Oncogene and microRNAs in Gastric Cancer: An Overview

Despite the advancements in cancer treatments, gastric cancer is still one of the leading causes of death worldwide. In this context, it is of great interest to discover new and more effective ways of treating this disease. Accumulated evidences have demonstrated the amplification of 8q24.21 region in gastric tumors. Furthermore, this is the region where the widely known MYC oncogene and different microRNAs are located. MYC deregulation is key in tumorigenesis in various types of tissues, once it is associated with cell proliferation, survival, and drug resistance. microRNAs are a class of noncoding RNAs that negatively regulate the protein translation, and which deregulation is related with gastric cancer development. However, little is understood about the interactions between microRNAs and MYC. Here, we overview the MYC role and its relationship with the microRNAs network in gastric cancer aiming to identify potential targets useful to be used in clinic, not only as biomarkers, but also as molecules for development of promising therapies.

Tumor-derived urinary exosomal long non-coding RNAs as diagnostic biomarkers for bladder cancer

Bladder cancer (BC) is the sixth most common malignancy in men and 17th in women. Exosomal long non-coding RNAs (lncRNAs) have been defined as a novel biomarker for BC. The aim of this study is to evaluate the clinical significance of urine exosomal PVT-1, ANRIL and PCAT-1 as a biomarker in BC patients with tumors classified as T1 or T2. Exosomes were isolated from urine of BC patients and healthy donors, then characterized according to their shape, size, and exosome markers by Electron Microscopy, Dynamic light scattering, and Western blotting. Exosomal lncRNAs extraction was done to determine the expression levels of PVT-1, ANRIL and PCAT-1 by qRT-PCR. ANRIL and PCAT-1 expression was significantly higher in BC patients compared to normal subjects. To evaluate the performance of the identified lncRNAs for BC detection, we performed ROC curves analysis. The diagnostic accuracy of ANRIL and PCAT-1, measured by AUC, was 0.7229 (sensitivity = 46.67 % and specificity = 87.5 %) and 0.7292 (sensitivity = 43.33 % and specificity = 87.5 %). Transcript levels of lncRNAs in urinary exosomes are potential diagnostic biomarkers in bladder cancer.

LncRNA XIST modulates HIF-1A/AXL signaling pathway by inhibiting miR-93-5p in colorectal cancer

Background

Long noncoding RNA (LncRNA) XIST is one of the genes that exists in different types of cancers. Earlier researches showed that XIST can advance the progression of colorectal cancer. Nevertheless, the potential molecular mechanism of XIST in combination with miR‐93‐5p has not been explored in colorectal cancer.

Methods

We performed qRT‐PCR to explore the level of XIST. And a serious experiments in vitro and in vivo were performed to explore the function of XIST. The relationship between XIST/HIF‐1A and miR‐93‐5p was confirmed by RIP and dual‐luciferase assays.

Results

In the present research, our team demonstrated the upregulation of XIST expression, which was related to tumor progression, and the downregulation of miR‐93‐5p in cells and tissues of colorectal cancer. XIST is the competitive endogenous RNA of miR‐93‐5p to promote HIF‐1A, and then the upregulated AXL level facilitates the EMT process, migration, and proliferation of colorectal cancer. At last, we proved that XIST enhanced the in vivo and in vitro activities of colorectal cancer by regulating AXL signaling.

Conclusion

In summary, the above results indicate that XIST promotes colorectal cancer tumorigenesis by regulating miR‐93‐5p/HIF‐1A/AXL signaling pathway, which will supply a novel perspective to diagnose and treat colorectal cancer disease.

PVT1 Long Non-coding RNA in Gastrointestinal Cancer

Whole genome and transcriptome sequencing technologies have led to the identification of many long non-coding RNAs (lncRNAs) and stimulated the research of their role in health and disease. LncRNAs participate in the regulation of critical signaling pathways including cell growth, motility, apoptosis, and differentiation; and their expression has been found dysregulated in human tumors. Thus, lncRNAs have emerged as new players in the initiation, maintenance and progression of tumorigenesis. PVT1 (plasmacytoma variant translocation 1) lncRNA is located on chromosomal 8q24.21, a large locus frequently amplified in human cancers and predictive of increased cancer risk in genome-wide association studies (GWAS). Combined, colorectal and gastric adenocarcinomas are the most frequent tumor malignancies and also the leading cause of cancer-related deaths worldwide. PVT1 expression is elevated in gastrointestinal tumors and correlates with poor patient prognosis. In this review, we discuss the mechanisms of action underlying PVT1 oncogenic role in colorectal and gastric cancer such as MYC upregulation, miRNA production, competitive endogenous RNA (ceRNA) function, protein stabilization, and epigenetic regulation. We also illustrate the potential role of PVT1 as prognostic biomarker and its relationship with resistance to current chemotherapeutic treatments.

p53 Activates the Long Noncoding RNA Pvt1b to Inhibit Myc and Suppress Tumorigenesis

The tumor suppressor p53 transcriptionally activates target genes to suppress cellular proliferation during stress. p53 has also been implicated in the repression of the proto-oncogene Myc, but the mechanism has remained unclear. Here, we identify Pvt1b, a p53-dependent isoform of the long noncoding RNA (lncRNA) Pvt1, expressed 50 kb downstream of Myc, which becomes induced by DNA damage or oncogenic signaling and accumulates near its site of transcription. We show that production of the Pvt1b RNA is necessary and sufficient to suppress Myc transcription in cis without altering the chromatin organization of the locus. Inhibition of Pvt1b increases Myc levels and transcriptional activity and promotes cellular proliferation. Furthermore, Pvt1b loss accelerates tumor growth, but not tumor progression, in an autochthonous mouse model of lung cancer. These findings demonstrate that Pvt1b acts at the intersection of the p53 and Myc transcriptional networks to reinforce the anti-proliferative activities of p53.