Amplification of lncRNA PVT1 promotes ovarian cancer proliferation by binding to miR-140

LncRNA PVT1 promotes malignant progression by regulating the miR-7-5p/CDKL1 axis in oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC), one of the most common types of head and neck squamous cell carcinoma (HNSCC), is characterized by high incidence and mortality. PVT1 is a long non-coding RNA (lncRNA) that plays an oncogenic role in various cancer types. This study aims to reveal the role and underlying molecular mechanism of PVT1 in OSCC progression. The expression levels of PVT1, miR-7-5p, and CDKL1 mRNA were evaluated using qRT-PCR. Western blot and IHC analysis were conducted to determine the protein expression of CDKL1. The biological functions of PVT1, miR-7-5p, and CDKL1 in OSCC were investigated through CCK-8, transwell migration and invasion assays. In vivo experiments utilized a xenograft model to examine the impact of PVT1 on OSCC. Furthermore, the interaction among PVT1, miR-7-5p, and CDKL1 was explored using RNA pull down assay and luciferase reporter assays. We found that PVT1 enhanced cell proliferation, migration, and invasion by targeting CDKL1. In addition, PVT1 functions as a sponge to modulate miR-7-5p, thereby influencing the expression of CDKL1 and the progression of OSCC. In conclusion, this study illustrates that the "PVT1/miR-7-5p/CDKL1" pathway is capable of promoting the progression of OSCC and may serve as a promising target for developing treatment strategies for OSCC.

LncRNAPVT1 is Associated with Cancer-Associated Fibroblasts Proliferation Through Regulating TGF-βin Oral Squamous Cell Carcinoma

INTRODUCTION

Human oral squamous cell carcinoma (OSCC) is the most common type of oral cancer and has a poor survival rate. Cell-cell communication between OSCC cells and cancer-associated fibroblasts (CAFs) plays important roles in OSCC progression. We previously demonstrated that CAFs promote OSCC cell migration and invasion. However, how OSCC cells influence CAFs proliferation is unknown.

METHODS

Knockdown of PVT1 was confirmed using lentivirus infection technique. CAFs in tissues were identified by staining the cells with α-SMA using immunohistochemical technique. CCK-8 assay was used to evaluate cell proliferation. The mRNA level of a gene was measured by qRT-PCR. Secreted TGF-β were detected using ELISA assay.

RESULTS

We found that knockdown of the long non-coding RNA (lncRNA) plasmacytoma variant translocation 1 (PVT1) was associated with a low density of CAFs in xenograft tumors in mice; further analysis revealed that PVT1 in OSCC cells induced CAF proliferation through transforming growth factor (TGF)-β.

DISCUSSION

Our results demonstrate that lncRNA PVT1 in tumor cells participates in CAF development in OSCC by regulating TGF-β. This study revealed a new mechanism by which PVT1 regulates OSCC progression and PVT1 is a potential therapeutic target in OSCC.

Current understanding of functional peptides encoded by lncRNA in cancer

Dysregulated gene expression and imbalance of transcriptional regulation are typical features of cancer. RNA always plays a key role in these processes. Human transcripts contain many RNAs without long open reading frames (ORF, > 100 aa) and that are more than 200 bp in length. They are usually regarded as long non-coding RNA (lncRNA) which play an important role in cancer regulation, including chromatin remodeling, transcriptional regulation, translational regulation and as miRNA sponges. With the advancement of ribosome profiling and sequencing technologies, increasing research evidence revealed that some ORFs in lncRNA can also encode peptides and participate in the regulation of multiple organ tumors, which undoubtedly opens a new chapter in the field of lncRNA and oncology research. In this review, we discuss the biological function of lncRNA in tumors, the current methods to evaluate their coding potential and the role of functional small peptides encoded by lncRNA in cancers. Investigating the small peptides encoded by lncRNA and understanding the regulatory mechanisms of these functional peptides may contribute to a deeper understanding of cancer and the development of new targeted anticancer therapies.

MicroRNAs, long non-coding RNAs, and circular RNAs and gynecological cancers: focus on metastasis

Gynecologic cancer is a significant cause of death in women worldwide, with cervical cancer, ovarian cancer, and endometrial cancer being among the most well-known types. The initiation and progression of gynecologic cancers involve a variety of biological functions, including angiogenesis and metastasis-given that death mostly occurs from metastatic tumors that have invaded the surrounding tissues. Therefore, understanding the molecular pathways underlying gynecologic cancer metastasis is critical for enhancing patient survival and outcomes. Recent research has revealed the contribution of numerous non-coding RNAs (ncRNAs) to metastasis and invasion of gynecologic cancer by affecting specific cellular pathways. This review focuses on three types of gynecologic cancer (ovarian, endometrial, and cervical) and three kinds of ncRNAs (long non-coding RNAs, microRNAs, and circular RNAs). We summarize the detailed role of non-coding RNAs in the different pathways and molecular interactions involved in the invasion and metastasis of these cancers.

Long non-coding RNA PVT1 promotes the proliferation, migration and EMT process of ovarian cancer cells by regulating CTGF

Ovarian cancer remains one of the most common gynecological malignancies with a poor prognosis. The present study investigated the roles of long non-coding RNA plasmacytoma variant translocation 1 (lncRNA PVT1) in the regulation of the malignant phenotype of ovarian cancer cells, including cell proliferation, migration, invasion and epithelial-mesenchymal transition (EMT). SKOV3 and CAOV3 cells were transfected with small interfering RNA (siRNA) targeting lncRNA PVT1 (si-PVT1) or control siRNA and the si-PVT1 transfected cells were co-cultured with recombinant human connective tissue growth factor (rhCTGF). The proliferation, migration and invasion abilities of the cells were examined via Cell Counting Kit-8, colony formation, wound-healing and Transwell assays. The relative expression levels of lncRNA PVT1, CTGF, E-cadherin and vimentin were analyzed using reverse transfection-quantitative polymerase chain reaction, and western blotting was employed to detect the protein levels of CTGF, E-cadherin and vimentin. The expression of lncRNA PVT1 was significantly reduced in SKOV3 and CAOV3 cells following transfection with si-PVT1. In addition, the proliferation, migration and invasion abilities of SKOV3 and CAOV3 cells were repressed following lncRNA PVT1 knockdown. The knockdown of lncRNA PVT1 also reduced the expression of CTGF and vimentin, and increased the expression of E-cadherin. The changes in the proliferation, migration and invasion of the cells induced by transfection with si-PVT1 were partially attenuated in the presence of rhCTGF. Furthermore, co-culture with rhCTGF reversed the si-PVT1-induced changes in the expression of EMT-associated proteins. In conclusion, lncRNA PVT1 promotes the proliferation, migration, invasiveness and EMT process of ovarian cancer cells, and CTGF contributes to the effect of lncRNA PVT1.

lncRNA PVT1: a novel oncogene in multiple cancers

Long noncoding RNAs are involved in epigenetic gene modification, including binding to the chromatin rearrangement complex in pre-transcriptional regulation and to gene promoters in gene expression regulation, as well as acting as microRNA sponges to control messenger RNA levels in post-transcriptional regulation. An increasing number of studies have found that long noncoding RNA plasmacytoma variant translocation 1 (PVT1) plays an important role in cancer development. In this review of a large number of studies on PVT1, we found that PVT1 is closely related to tumor onset, proliferation, invasion, epithelial–mesenchymal transformation, and apoptosis, as well as poor prognosis and radiotherapy and chemotherapy resistance in some cancers. This review comprehensively describes PVT1 expression in various cancers and presents novel approaches to the diagnosis and treatment of cancer.

PVT1 is a stress-responsive lncRNA that drives ovarian cancer metastasis and chemoresistance

Metastatic growth of ovarian cancer cells into the peritoneal cavity requires adaptation to various cellular stress factors to facilitate cell survival and growth. Here, we demonstrate the role of PVT1, one such stress induced long non-coding RNA, in ovarian cancer growth and metastasis. PVT1 is an amplified and overexpressed lncRNA in ovarian cancer with strong predictive value for survival and response to targeted therapeutics. We find that expression of PVT1 is regulated by tumor cells in response to cellular stress, particularly loss of cell-cell contacts and changes in matrix rigidity occurring in a YAP1-dependent manner. Induction of PVT1 promotes tumor cell survival, growth, and migration. Conversely, reducing PVT1 levels robustly abrogates metastatic behavior and tumor cell dissemination in cell lines and syngeneic transplantation models in vivo. We find that reducing PVT1 causes widespread changes in the transcriptome leading to alterations in cellular stress response and metabolic pathways including doxorubicin metabolism, which impacts chemosensitivity. Together, these findings implicate PVT1 as a promising therapeutic target to suppress metastasis and chemoresistance in ovarian cancer.

Inhibition of the lncRNA DANCR attenuates cardiomyocyte injury induced by oxygen-glucose deprivation via the miR-19a-3p/MAPK1 axis

Long noncoding RNAs (lncRNAs) have been considered as crucial regulators of acute myocardial infarction (AMI). In this study, to analyze the effect of differentiation antagonizing nonprotein coding RNA (DANCR) of lncRNA on cardiomyocyte damage in AMI, cardiomyocyte injury was induced by oxygen-glucose deprivation (OGD). Cell counting kit-8 (CCK-8) assay and flow cytometry were used to assess cell viability and apoptosis, respectively. Quantitative real-time PCR was used to measure the expression levels of DANCR and miR-19a-3p. Bioinformatics analysis and luciferase gene reporter assay were utilized to explore the relationship among DANCR, miR-19a-3p, and mitogen-activated protein kinase 1 (MAPK1). CCK-8 and TUNEL assays were used to explore the effects of DANCR alone or plus miR-19a-3p on the viability and apoptosis of OGD/R-exposed HL-1 cells. Western blot analysis was used to detect changes in the MAPK1/ERK1/2 pathway in HL-1 cells. We found that DANCR expression and miR-19a-3p level are negatively correlated as DANCR expression is increased, while miR-19a-3p level is decreased in AMI patients' serum and OGD/R-exposed HL-1 cells. DANCR knockdown increased miR-19a-3p level, and miR-19a-3p inhibition increased DANCR expression. Moreover, DANCR directly binds to miR-19a-3p. DANCR knockdown reduced viability but induced apoptosis in OGD/R-exposed HL-1 cells, while miR-19a-3p inhibition weakens these effects. Furthermore, MAPK1 is a target of miR-19a-3p. miR-19a-3p overexpression decreases MAPK1 and ERK1/2 in HL-1 cells, while miR-19a-3p inhibition increases MAPK1 and ERK1/2 in HL-1 cells. Moreover, DANCR knockdown reduces myocardium apoptosis in mice with the left anterior descending artery ligated. DANCR knockdown effectively restores myocardial cell apoptosis by regulating the miR-19a-3p/MAPK1/ERK1/2 axis.

Long Non-coding RNA PVT1 Inhibits miR-30c-5p to Upregulate Rock2 to Modulate Cerebral Ischemia/Reperfusion Injury Through MAPK Signaling Pathway Activation

Long non-coding RNAs (lncRNAs) play a key role in a variety of disease processes. Plasmacytoma variant translocation 1 (PVT1), a lncRNA, is known to regulate cell functions and play a key role in the pathogenesis of many malignant tumors. The function and molecular mechanisms of lncRNA-PVT1 in cerebral ischemia remain unknown. Real-time PCR (qRT-PCR) was used to detect lncRNA-PVT1 and microRNA-30c-5p (miR-30c-5p) expression in the brain tissues of mice underwent middle cerebral artery occlusion/reperfusion (MCAO/R) and oxygen-glucose deprivation/reperfusion (OGD/R)-treated mouse primary brain neurons. Gain- or loss-of-function approaches were used to manipulate PVT1, miR-30c-5p, and Rho-associated protein kinase 2 (Rock2). The mechanism of PVT1 in ischemic stroke was evaluated both in vivo and in vitro via bioinformatics analysis, CCK-8, flow cytometry, TUNEL staining, luciferase activity assay, RNA FISH, and Western blot. PVT1 was upregulated in the brain tissues of mice treated with MCAO/R and primary cerebral cortex neurons of mice treated with OGD/R. Mechanistically, PVT1 knockdown resulted in a lower infarct volume and ameliorated neurobehavior in MCAO mice. Consistent with in vivo results, PVT1 upregulation significantly decreased the viability and induced apoptosis of neurons cultured in OGD/R. Moreover, we demonstrated that PVT1 acts as a competitive endogenous RNA (ceRNA) that competes with miR-30c-5p, thereby negatively regulating its endogenous target Rock2. Overexpression of miR-30c-5p significantly promoted cell proliferation and inhibited apoptosis. Meanwhile, PVT1 was confirmed to target miR-30c-5p, thus activating Rock2 expression, which finally led to the activation of MAPK signaling. We demonstrated that PVT1, as a ceRNA of miR-30c-5p, could target and regulate the level of Rock2, which aggravates cerebral I/R injury via activation of the MAPK pathway. These findings reveal a new function of PVT1, which helps to broadly understand cerebral ischemic stroke and provide a new treatment strategy for this disease.

Deciphering the Long Non-Coding RNAs and MicroRNAs Coregulation Networks in Ovarian Cancer Development: An Overview

Non-coding RNAs are emergent elements from the genome, which do not encode for proteins but have relevant cellular functions impacting almost all the physiological processes occurring in eukaryotic cells. In particular, microRNAs and long non-coding RNAs (lncRNAs) are a new class of small RNAs transcribed from the genome, which modulate the expression of specific genes at transcriptional and posttranscriptional levels, thus adding a new regulatory layer in the flux of genetic information. In cancer cells, the miRNAs and lncRNAs interactions with its target genes and functional pathways are deregulated as a consequence of epigenetic and genetic alterations occurring during tumorigenesis. In this review, we summarize the actual knowledge on the interplay of lncRNAs with its cognate miRNAs and mRNAs pairs, which interact in coregulatory networks with a particular emphasis on the mechanisms underlying its oncogenic behavior in ovarian cancer. Specifically, we reviewed here the evidences unraveling the relevant roles of lncRNAs/miRNAs pairs in altered regulation of cell migration, angiogenesis, therapy resistance, and Warburg effect. Finally, we also discussed its potential clinical implications in ovarian cancer and related endocrine disease therapies.

Long non-coding RNA-H19 promotes ovarian cancer cell proliferation and migration via the microRNA-140/Wnt1 axis

To explore the effect and underlying molecular mechanism of long non-coding RNA (lncRNA)-H19 on ovarian cancer (OC) cells, a total of 41 cases of OC and adjacent normal tissues were collected. H19 and microRNA (miR)-140 expressions in OC tissues and cells were detected using quantitative real-time polymerase chain reaction (qRT-RCR). The correlation between H19 expression and prognosis of OC patient was analyzed. siRNA (si)-H19 and si-negative control (NC) were transfected into OC cells. Cell proliferation was checked by cell counting kit-8 assay and colony formation assay, and cell migration and invasion were analyzed via Transwell assay. The targeted binding relationship between H19 and miR-140 was predicted and verified, miR-140 downstream gene was predicted and Wnt1 was screened out. The impact of in-miR-140 on the si-H19-induced decreased OC cell proliferation and migration was evaluated. H19 expression was upregulated in OC tissues and cells, and its overexpression was associated with a poor prognosis of OC. si-H19 remarkably reduced OC cell proliferation and migration. H19 upregulated Wnt1 expression through targeting miR-140 in OC cells. Altogether, miR-140 was notably downregulated in OC, and in-miR-140 partially inhibited the si-H19-induced decrease of OC cell proliferation and migration. H19 competitively bound to miR-140 to upregulate Wnt1, thereby promoting OC cell proliferation and migration.

microRNA-140: A miRNA with diverse roles in human diseases

MicroRNA-140 (miR-140) has been shown to be associated with the pathogenesis of a wide range of pathologies including osteoarthritis, osteoporosis, renal fibrosis, ischemic conditions, and most importantly neoplasia. This miRNA has been shown to be down-regulated in a diversity of cancers namely breast cancer, gastrointestinal cancers, lung cancer, and prostate cancer. miR-140 has a lot of immune-related targets. Moreover, several miR-140 targets regulate cell proliferation, cell cycle transition, and apoptosis. This miRNA has been shown to be sponged by a number of lncRNAs and circ-RNAs. miR-140 has essential roles in the determination of the sensitivity of neoplastic cells to chemotherapeutic agents such as temozolomide, doxorubicin, and cisplatin. Besides, expression quantities of miR-140 in cancer tissues can be used for the prediction of clinical outcomes of patients with neoplasia. In the present paper, we describe the impact of miR-140 in neoplastic and non-neoplastic disorders.

8q24.21 Locus: A Paradigm to Link Non-Coding RNAs, Genome Polymorphisms and Cancer

The majority of the human genome is comprised of non-protein-coding genes, but the relevance of non-coding RNAs in complex diseases has yet to be fully elucidated. One class of non-coding RNAs is long non-coding RNAs or lncRNAs, many of which have been identified to play a range of roles in transcription and translation. While the clinical importance of the majority of lncRNAs have yet to be identified, it is puzzling that a large number of disease-associated genetic variations are seen in lncRNA genes. The 8q24.21 locus is rich in lncRNAs and very few protein-coding genes are located in this region. Interestingly, the 8q24.21 region is also a hot spot for genetic variants associated with an increased risk of cancer. Research focusing on the lncRNAs in this area of the genome has indicated clinical relevance of lncRNAs in different cancers. In this review, we summarise the lncRNAs in the 8q24.21 region with respect to their role in cancer and discuss the potential impact of cancer-associated genetic polymorphisms on the function of lncRNAs in initiation and progression of cancer.

Gynecologic cancers and non-coding RNAs: Epigenetic regulators with emerging roles

Gynecologic cancers involve the female genital organs, such as the vulva, vagina, cervix, endometrium, ovaries, and fallopian tubes. The occurrence and frequency of gynecologic cancer depends on personal lifestyle, history of exposure to viruses or carcinogens, genetics, body shape, and geographical habitat. For a long time, research into the molecular biology of cancer was broadly restricted to protein-coding genes. Recently it has been realized that non-coding RNAs (ncRNA), including long noncoding RNAs (LncRNAs), microRNAs, circular RNAs and piRNAs (PIWI-interacting RNAs), can all play a role in the regulation of cellular function within gynecological cancer. It is now known that ncRNAs are able to play dual roles, i.e. can exert both oncogenic or tumor suppressive functions in gynecological cancer. Moreover, several clinical trials are underway looking at the biomarker and therapeutic roles of ncRNAs. These efforts may provide a new horizon for the diagnosis and treatment of gynecological cancer. Herein, we summarize some of the ncRNAs that have been shown to be important in gynecological cancers.

LncRNAs in Ovarian Cancer Progression, Metastasis, and Main Pathways: ceRNA and Alternative Mechanisms

Ovarian cancer (OvCa) develops asymptomatically until it reaches the advanced stages with metastasis, chemoresistance, and poor prognosis. Our review focuses on the analysis of regulatory long non-coding RNAs (lncRNAs) competing with protein-coding mRNAs for binding to miRNAs according to the model of competitive endogenous RNA (ceRNA) in OvCa. Analysis of publications showed that most lncRNAs acting as ceRNAs participate in OvCa progression: migration, invasion, epithelial-mesenchymal transition (EMT), and metastasis. More than 30 lncRNAs turned out to be predictors of survival and/or response to therapy in patients with OvCa. For a number of oncogenic (CCAT1, HOTAIR, NEAT1, and TUG1 among others) and some suppressive lncRNAs, several lncRNA/miRNA/mRNA axes were identified, which revealed various functions for each of them. Our review also considers examples of alternative mechanisms of actions for lncRNAs besides being ceRNAs, including binding directly to mRNA or protein, and some of them (DANCR, GAS5, MALAT1, and UCA1 among others) act by both mechanisms depending on the target protein. A systematic analysis based on the data from literature and Panther or KEGG (Kyoto Encyclopedia of Genes and Genomes) databases showed that a significant part of lncRNAs affects the key pathways involved in OvCa metastasis, EMT, and chemoresistance.

LncRNA PVT1 Is a Poor Prognosticator and Can Be Targeted by PVT1 Antisense Oligos in Gastric Adenocarcinoma

Gastric adenocarcinoma (GAC) is inherently resistant or becomes resistant to therapy, leading to a poor prognosis. Mounting evidence suggests that lncRNAs can be used as predictive markers and therapeutic targets in the right context. In this study, we determined the role of lncRNA-PVT1 in GAC along with the value of inhibition of PVT1 using antisense oligos (ASOs). RNA scope in situ hybridization was used to analyze PVT1 expression in tumor tissue microarrays (TMAs) of GAC and paired normal tissues from 792 patients. Functional experiments, including colony formation and invasion assays, were performed to evaluate the effects of PVT1 ASO inhibition of PVT1 in vitro; patient-derived xenograft models were used to evaluate the anti-tumor effects of PVT1 ASOs in vivo. LncRNA-PVT1 was upregulated in GACs compared to the matched adjacent normal tissues in the TMA. LncRNA PVT1 expression was positively correlated with larger tumor size, deeper wall invasion, lymph node metastases, and short survival duration. Inhibition of PVT1 using PVT1 ASOs significantly suppressed tumor cell growth and invasion in vitro and in vivo. PVT1 expression was highly associated with poor prognosis in GAC patients and targeting PVT1 using PVT1 ASOs was effective at curtailing tumor cell growth in vitro and in vivo. Thus, PVT1 is a poor prognosticator as well as therapeutic target. Targeting PVT1 using PVT1 ASOs provides a novel therapeutic strategy for GAC.

Knockdown of PVT1 Suppresses Colorectal Cancer Progression by Regulating MiR-106b-5p/FJX1 Axis

Purpose

Long non-coding RNA plasmacytoma variant translocation 1 (PVT1) has been revealed to involve in the progression of CRC. However, the precise mechanisms of PVT1 in action remain unclear.

Methods

The expression of PVT1, microRNA-106b-5p (miR-106b-5p) and four jointed box 1 (FJX1) was measured using quantitative real-time polymerase chain reaction (qRT-PCR) or Western blot, respectively. Cell proliferation was investigated by 3-(4,5)-dimethylthiahiazo (−z-y1)-3,5-di-phenytetrazoliumromide assay. Transwell assay was used to determine cell migration and invasion. The correlation between miR-106b-5p and PVT1 or FJX1 was confirmed using luciferase reporter assay. The effects of PVT1 in vivo were assessed using mice xenograft model.

Results

PVT1 was up-regulated in CRC tissues and cell lines, especially in CRC tissues with high-grade, and highly expressed PVT1 predicted worse prognosis. Functional experiments demonstrated that PVT1 deletion inhibited CRC cell proliferation, migration and invasion in vitro and suppressed tumor growth in vivo. MiR-106b-5p was confirmed to be a target of PVT1, and inhibition of miR-106b-5p reversed the inhibitory effects of PVT1 knockdown on CRC cell malignant phenotypes. In addition, we found miR-106b-5p directly targeted FJX1, and miR-106b-5p-mediated inhibition on CRC cell proliferation, migration and invasion was attenuated by FJX1 up-regulation. Importantly, it was also proved that PVT1 could indirectly regulate FJX1 expression via targeting miR-106b-5p.

Conclusion

Knockdown of PVT1 impaired cell proliferation, migration and invasion in CRCs via regulating miR-106b-5p/FJX1 axis, which provided a novel insight into the development of therapeutic strategies for CRC patients.

Cancer and SOX proteins: New insight into their role in ovarian cancer progression/inhibition

Transcription factors are potential targets in disease therapy, particularly in cancer. This is due to the fact that transcription factors regulate a variety of cellular events, and their modulation has opened a new window in cancer therapy. Sex-determining region Y (SRY)-related high-mobility group (HMG) box (SOX) proteins are potential transcription factors that are involved in developmental processes such as embryogenesis. It has been reported that abnormal expression of SOX proteins is associated with development of different cancers, particularly ovarian cancer (OC). In the present review, our aim is to provide a mechanistic review of involvement of SOX members in OC. SOX members may suppress and/or promote aggressiveness and proliferation of OC cells. Clinical studies have also confirmed the potential of transcription factors as diagnostic and prognostic factors in OC. Notably, studies have demonstrated the relationship between SOX members and other molecular pathways such as ST6Ga1-I, PI3K, ERK and so on, leading to more complexity. Furthermore, SOX members can be affected by upstream mediators such as microRNAs, long non-coding RNAs, and so on. It is worth mentioning that the expression of each member of SOX proteins is corelated with different stages of OC. Furthermore, their expression determines the response of OC cells to chemotherapy. These topics are discussed in this review to shed some light on role of SOX transcription factors in OC.

Upregulation of lncRNA plasmacytoma variant translocation 1 predicts poor prognosis in patients with muscle-invasive bladder cancer

LncRNA plasmacytoma variant translocation 1 (PVT1) has been recognized as an oncogenic lncRNA, which participates in the migration and invasion of many kinds of cancer cells and the development of cancers. In the present study, we explored its clinical significance and prognostic value in muscle invasive bladder cancer (MIBC).A total of 98 MIBC patients' samples were collected, who had undergone radical cystectomy from the March 2013 to December 2018. The associations between PVT1 expression and clinical data were calculated using the Chi-test. Overall survival curves were determined by the Kaplan-Meier technique and contrasted via log-rank test. We utilized univariate and multivariate Cox proportional hazard models to examine the HR and 95% CI.The expression levels of PVT1 were significantly higher in MIBC tissues than that in normal bladder tissues (P < .001). PVT1 expression was significantly correlated with tumor grade (P = .009), margin (P = .002), T stage (P = .02), and lymph node metastasis (P < .001). MIBC patients with high PVT1 expression level had shorter overall survival than those with low PVT1 expression level (log-rank test, P = .004). Multivariate Cox regression analysis showed that PVT1 expression level (HR = 2.381, 95% CI: 1.821-7.012, P = .014) was an independent factor in predicting the overall survival of MIBC patients.In summary, increased PVT1 expression in MIBC patients is correlated with a higher MIBC stage and is significantly associated with poor prognosis for MIBC patients, which may provide new insights into new therapeutic strategy and postoperative intervention against bladder cancer.

The Challenges and Opportunities of LncRNAs in Ovarian Cancer Research and Clinical Use

Ovarian cancer is one of the most lethal gynecological malignancies worldwide because it tends to be detected late, when the disease has already spread, and prognosis is poor. In this review we aim to highlight the importance of long non-coding RNAs (lncRNAs) in diagnosis, prognosis and treatment choice, to make progress towards increasingly personalized medicine in this malignancy. We review the effects of lncRNAs associated with ovarian cancer in the context of cancer hallmarks. We also discuss the molecular mechanisms by which lncRNAs become involved in cellular physiology; the onset, development and progression of ovarian cancer; and lncRNAs' regulatory mechanisms at the transcriptional, post-transcriptional and post-translational stages of gene expression. Finally, we compile a series of online resources useful for the study of lncRNAs, especially in the context of ovarian cancer. Future work required in the field is also discussed along with some concluding remarks.

LOXL1-AS1 Drives The Progression Of Gastric Cancer Via Regulating miR-142-5p/PIK3CA Axis

Background

Gastric cancer (GC) is a deadly disease, and its incidence is especially high in East Asia including China. Recently, some long non-coding RNA (lncRNAs) have been identified as oncogenes or tumor suppressors. This study aimed to determine the function and mechanism of lncRNA LOXL1-AS1 on the progression of GC.

Methods

RT-PCR was done to measure the expression levels of LOXL1-AS1 and miR-142-5p in GC tissues. The association between pathological indexes and LOXL1-AS1 expression was also analyzed. Human GC cell lines AGS and BGC823 were used as cell models. CCK-8 and colony formation assays were conducted to assess the effect of LOXL1-AS1 on the proliferation of GC cell lines. Transwell assay was conducted to determine the influence of LOXL1-AS1 on cell migration and invasion. Furthermore, luciferase reporter assay was carried out to confirm the relationship of miR-142-5p with LOXL1-AS1. Additionally, Western blot was done to detect the regulatory function of LOXL1-AS1 on PIK3CA, a target of miR-142-5p. In vivo experiment was also performed to validate the roles and mechanism of LOXL1-AS1 on the growth and metastasis of GC cells.

Results

LOXL1-AS1 expression in GC samples was significantly increased, which was correlated with unfavorable pathological indexes. Highly expressed LOXL1-AS1 was closely linked to shorter overall survival time and post-progression survival time of the patients. LOXL1-AS1 markedly modulated the malignant phenotypes of GC cells. Additionally, overexpressed LOXL1-AS1 notably reduced the expression of miR-142-5p, but enhanced the expression level of PIK3CA. In vivo experiments further validated that knockdown of LOXL1-AS1 inhibited the growth and metastasis of GC cells via regulating miR-142-5p and PIK3CA.

Conclusion

LOXL1-AS1 was a sponge of tumor suppressor miR-142-5p in GC, enhanced the expression of PIK3CA indirectly and functioned as an oncogenic lncRNA.

Long Non-coding RNA PVT1 as a Prognostic and Therapeutic Target in Pediatric Cancer

In recent decades, biomedical research has focused on understanding the functionality of the human translated genome, which represents a minor part of all genetic information transcribed from the human genome. However, researchers have become aware of the importance of non-coding RNA species that constitute the vast majority of the transcriptome. In addition to their crucial role in tissue development and homeostasis, mounting evidence shows non-coding RNA to be deregulated and functionally contributing to the development and progression of different types of human disease including cancer both in adults and children. Small non-coding RNAs (i.e., microRNA) are in the vanguard of clinical research which revealed that RNA could be used as disease biomarkers or new therapeutic targets. Furthermore, many more expectations have been raised for long non-coding RNAs, by far the largest fraction of non-coding transcripts, and still fewer findings have been translated into clinical applications. In this review, we center on PVT1, a large and complex long non-coding RNA that usually confers oncogenic properties on different tumor types. We focus on the compilation of early advances in the field of pediatric tumors which often lags behind clinical improvements in adult tumors, and provide a rationale to continue studying PVT1 as a possible functional contributor to pediatric malignancies and as a potential prognostic marker or therapeutic target.

LncRNA PVT1 promotes proliferation and invasion through enhancing Smad3 expression by sponging miR-140-5p in cervical cancer

Background

Cervical cancer is one of the most frequent malignancies among females worldwide. Increasing evidence have indicated the participation of long noncoding RNAs (lncRNAs) in the progression and metastasis of cervical cancer. Our present study was conducted to explore the effects of lncRNA plasmacytoma variant translocation 1 (PVT1) on the progression of cervical cancer and the underlying mechanisms.

Materials and methods

Expressions of PVT1, miR-140-5p and Smad3 in cervical cancer cell lines were detected by qRT-PCR and western blotting. Bioinformatics analysis and luciferase assays were used to elucidate the potential correlations between PVT1, miR-140-5p and Smad3. The roles of PVT1 on the progression of cervical cancer cells were determined by transfecting sh-RNA through series function assays such as colony formation assay, wound healing assay, transwell assay.

Results

PVT1 and Smad3 were upregulated, and miR-140-5p was downregulated in cervical cancer cells. PVT1 could bind directly with miR-140-5p, and Smad3 was a downstream target of miR-140-5p. Inhibition of PVT1 could enhance expression of miR-140-5p, inhibit the expression of Smad3, significantly inhibited the proliferation, migration, invasion in cervical cancer cells. While transfection of miR-140-5p inhibitor could partially reverse the above changes in cervical cancer cells.

Conclusions

The results revealed that PVT1 could promote the proliferation and metastasis via increasing the Smad3 expression by sponging miR-140-5p, which might be a promising prognostic and therapeutic target for cervical cancer.