LSINCT5 activates Wnt/β-catenin signaling by interacting with NCYM to promote bladder cancer progression

Wnt/β-catenin-driven EMT regulation in human cancers

Metastasis accounts for 90% of cancer-related deaths among the patients. The transformation of epithelial cells into mesenchymal cells with molecular alterations can occur during epithelial-mesenchymal transition (EMT). The EMT mechanism accelerates the cancer metastasis and drug resistance ability in human cancers. Among the different regulators of EMT, Wnt/β-catenin axis has been emerged as a versatile modulator. Wnt is in active form in physiological condition due to the function of GSK-3β that destructs β-catenin, while ligand-receptor interaction impairs GSK-3β function to increase β-catenin stability and promote its nuclear transfer. Regarding the oncogenic function of Wnt/β-catenin, its upregulation occurs in human cancers and it can accelerate EMT-mediated metastasis and drug resistance. The stimulation of Wnt by binding Wnt ligands into Frizzled receptors can enhance β-catenin accumulation in cytoplasm that stimulates EMT and related genes upon nuclear translocation. Wnt/β-catenin/EMT axis has been implicated in augmenting metastasis of both solid and hematological tumors. The Wnt/EMT-mediated cancer metastasis promotes the malignant behavior of tumor cells, causing therapy resistance. The Wnt/β-catenin/EMT axis can be modulated by upstream mediators in which non-coding RNAs are main regulators. Moreover, pharmacological intervention, mainly using phytochemicals, suppresses Wnt/EMT axis in metastasis suppression.

Pathological role of long non-coding (lnc) RNA in the regulation of Wnt/β-catenin signaling pathway during epithelial-mesenchymal transition (EMT)

The term "epithelial-mesenchymal transition" (EMT) describes a biological process wherein epithelial cells acquire mesenchymal cell characteristics. This process enables the metastatic cells to migrate and invasion. Recent studies have established the connections between the EMT process and Wnt/β-catenin signaling in cancer. Key cellular functions such as differentiation, proliferation, migration, genetic stability, apoptosis, and stem cell renewal are modulated via Wnt/ β-catenin signaling pathway. Up-regulation of this evolutionarily conserved signal pathway leads to EMT. On the other hand, recent investigations have indicated that non-coding RNAs including microRNAs (miRNAs) and long non-coding RNA (lncRNAs) are involved in regulating of Wnt/β-catenin pathway. A high level of lncRNAs mainly has a positive correlation with EMT. However, lncRNA down-regulation has been observed in promoting EMT. It seems that depending on the specific targets, up-or down-regulation of lncRNAs can stimulate EMT by activating the Wnt/ β-catenin pathway. The evaluation of interactions between lncRNAs and the Wnt/ β-catenin signaling pathway in the regulation of EMT during metastasis can be fascinating. Herein, for the first time, the crucial role of lncRNAs-mediated regulation of the Wnt/ β-catenin signaling pathway in the EMT process of human tumors has been summarized.

A hybrid approach to assess the structural impact of long noncoding RNA mutations uncovers key NEAT1 interactions in colorectal cancer

Long noncoding RNAs (lncRNAs) are emerging players in cancer and they entail potential as prognostic biomarkers or therapeutic targets. Earlier studies have identified somatic mutations in lncRNAs that are associated with tumor relapse after therapy, but the underlying mechanisms behind these associations remain unknown. Given the relevance of secondary structure for the function of some lncRNAs, some of these mutations may have a functional impact through structural disturbance. Here, we examined the potential structural and functional impact of a novel A > G point mutation in NEAT1 that has been recurrently observed in tumors of colorectal cancer patients experiencing relapse after treatment. Here, we used the nextPARS structural probing approach to provide first empirical evidence that this mutation alters NEAT1 structure. We further evaluated the potential effects of this structural alteration using computational tools and found that this mutation likely alters the binding propensities of several NEAT1-interacting miRNAs. Differential expression analysis on these miRNA networks shows upregulation of Vimentin, consistent with previous findings. We propose a hybrid pipeline that can be used to explore the potential functional effects of lncRNA somatic mutations.

The Origins and Functions of De Novo Genes: Against All Odds?

"De novo" genes evolve from previously non-genic DNA. This strikes many of us as remarkable, because it seems extraordinarily unlikely that random sequence would produce a functional gene. How is this possible? In this two-part review, I first summarize what is known about the origins and molecular functions of the small number of de novo genes for which such information is available. I then speculate on what these examples may tell us about how de novo genes manage to emerge despite what seem like enormous opposing odds.

RHO GTPase-Related Long Noncoding RNAs in Human Cancers

RHO GTPases are critical signal transducers that regulate cell adhesion, polarity, and migration through multiple signaling pathways. While all these cellular processes are crucial for the maintenance of normal cell homeostasis, disturbances in RHO GTPase-associated signaling pathways contribute to different human diseases, including many malignancies. Several members of the RHO GTPase family are frequently upregulated in human tumors. Abnormal gene regulation confirms the pivotal role of lncRNAs as critical gene regulators, and thus, they could potentially act as oncogenes or tumor suppressors. lncRNAs most likely act as sponges for miRNAs, which are known to be dysregulated in various cancers. In this regard, the significant role of miRNAs targeting RHO GTPases supports the view that the aberrant expression of lncRNAs may reciprocally change the intensity of RHO GTPase-associated signaling pathways. In this review article, we summarize recent advances in lncRNA research, with a specific focus on their sponge effects on RHO GTPase-targeting miRNAs to crucially mediate gene expression in different cancer cell types and tissues. We will focus in particular on five members of the RHO GTPase family, including RHOA, RHOB, RHOC, RAC1, and CDC42, to illustrate the role of lncRNAs in cancer progression. A deeper understanding of the widespread dysregulation of lncRNAs is of fundamental importance for confirmation of their contribution to RHO GTPase-dependent carcinogenesis.

Biological functions and clinical significance of long noncoding RNAs in bladder cancer

Bladder cancer (BCa) is one of the 10 most common cancers with high morbidity and mortality worldwide. Long noncoding RNAs (lncRNAs), a large class of noncoding RNA transcripts, consist of more than 200 nucleotides and play a significant role in the regulation of molecular interactions and cellular pathways during the occurrence and development of various cancers. In recent years, with the rapid advancement of high-throughput gene sequencing technology, several differentially expressed lncRNAs have been discovered in BCa, and their functions have been proven to have an impact on BCa development, such as cell growth and proliferation, metastasis, epithelial-mesenchymal transition (EMT), angiogenesis, and drug-resistance. Furthermore, evidence suggests that lncRNAs are significantly associated with BCa patients' clinicopathological characteristics, especially tumor grade, TNM stage, and clinical progression stage. In addition, lncRNAs have the potential to more accurately predict BCa patient prognosis, suggesting their potential as diagnostic and prognostic biomarkers for BCa patients in the future. In this review, we briefly summarize and discuss recent research progress on BCa-associated lncRNAs, while focusing on their biological functions and mechanisms, clinical significance, and targeted therapy in BCa oncogenesis and malignant progression.

Secondary Structure of Human De Novo Evolved Gene Product NCYM Analyzed by Vacuum-Ultraviolet Circular Dichroism

NCYM, a cis-antisense gene of MYCN, encodes a Homininae-specific protein that promotes the aggressiveness of human tumors. Newly evolved genes from non-genic regions are known as de novo genes, and NCYM was the first de novo gene whose oncogenic functions were validated in vivo. Targeting NCYM using drugs is a potential strategy for cancer therapy; however, the NCYM structure must be determined before drug design. In this study, we employed vacuum-ultraviolet circular dichroism to evaluate the secondary structure of NCYM. The SUMO-tagged NCYM and the isolated SUMO tag in both hydrogenated and perdeuterated forms were synthesized and purified in a cell-free in vitro system, and vacuum-ultraviolet circular dichroism spectra were measured. Significant differences between the tagged NCYM and the isolated tag were evident in the wavelength range of 190–240 nm. The circular dichroism spectral data combined with a neural network system enabled to predict the secondary structure of NCYM at the amino acid level. The 129-residue tag consists of α-helices (approximately 14%) and β-strands (approximately 29%), which corresponded to the values calculated from the atomic structure of the tag. The 238-residue tagged NCYM contained approximately 17% α-helices and 27% β-strands. The location of the secondary structure predicted using the neural network revealed that these secondary structures were enriched in the Homininae-specific region of NCYM. Deuteration of NCYM altered the secondary structure at D90 from an α-helix to another structure other than α-helix and β-strand although this change was within the experimental error range. All four nonsynonymous single-nucleotide polymorphisms (SNPs) in human populations were in this region, and the amino acid alteration in SNP N52S enhanced Myc-nick production. The D90N mutation in NCYM promoted NCYM-mediated MYCN stabilization. Our results reveal the secondary structure of NCYM and demonstrated that the Homininae-specific domain of NCYM is responsible for MYCN stabilization.

Role of Long Non-coding RNAs on Bladder Cancer

Bladder cancer (BC) is the most common malignant tumor in the urinary system, and its early diagnosis is conducive to improving clinical prognosis and prolonging overall survival time. However, few biomarkers with high sensitivity and specificity are used as diagnostic markers for BC. Multiple long non-coding RNAs (lncRNAs) are abnormally expressed in BC, and play key roles in tumorigenesis, progression and prognosis of BC. In this review, we summarize the expression, function, molecular mechanisms and the clinical significance of lncRNAs on bladder cancer. There are more than 100 dysregulated lncRNAs in BC, which are involved in the regulation of proliferation, cell cycle, apoptosis, migration, invasion, metabolism and drug resistance of BC. Meanwhile, the molecular mechanisms of lncRNAs in BC was explored, including lncRNAs interacting with DNA, RNA and proteins. Additionally, the abnormal expression of thirty-six lncRNAs is closely associated with multiple clinical characteristics of BC, including tumor size, metastasis, invasion, and drug sensitivity or resistance of BC. Furthermore, we summarize some potential diagnostic and prognostic biomarkers of lncRNA for BC. This review provides promising novel biomarkers in early diagnosis, prognosis and monitoring of BC based on lncRNAs.

LncRNA LSINCT5/miR-222 regulates myocardial ischemia‑reperfusion injury through PI3K/AKT pathway

Cardiovascular diseases rank the top cause of morbidity and mortality worldwide and are usually associated with blood reperfusion after myocardial ischemia/reperfusion injury (MIRI), which often causes severe pathological damages and cardiomyocyte apoptosis. LSINCT5 expression in the plasma of MI patients (n = 53), healthy controls (n = 42) and hypoxia-reoxygenation (HR)-treated cardiomyocyte AC16 cells was examined using qRT-PCR. The effects of LSINCT5 on cell viability and apoptosis were detected by MTT and flow cytometry, respectively. The expression of apoptosis-related proteins Bcl2, Bax and caspase 3 were tested by Western blot. The interaction between LSINCT5 and miR-222 was predicted by bioinformatic analysis. Moreover, changes in viability and apoptosis of AC16 cells co-transfected with siLSINCT5 and miR-222 inhibitor after HR treatment were examined. At last, the expression of proteins in PI3K/AKT pathway, namely PTEN, PI3K and AKT, was examined to analyze the possible pathway participating in LSINCT5-mediated MI/RI. Our study showed that LSINCT5 expression was upregulated in the plasma of MI patients and HR-treated AC16 cells. LSINCT5 overexpression significantly decreased cell viability and apoptosis. Luciferase reporter gene assay and RNA pulldown assay showed that LSINCT5 was a molecular sponge of miR-222. MiR-222 silencing in AC16 cells simulated the phenotypes of MIRI patients and HR-treated cells, indicating that LSINCT5 functions via miR-222 to regulate proliferation and apoptosis of HR-treated AC16 cells. We also showed that proteins of PI3K/AKT signaling pathway were affected in HR-treated AC16 cells, and LSINTC5 knockdown rescued these effects. LncRNA LSINCT5 was upregulated during MI pathogenesis, and LSINCT5 regulated MIRI possibly via a potential LSINCT5/miR-222 axis and PI3K/AKT signaling pathway. Our findings may provide novel evidence for MIRI prevention.

Silencing of the Long Noncoding RNA MYCNOS1 Suppresses Activity of MYCN-Amplified Retinoblastoma Without RB1 Mutation

Purpose

MYCNOS (MYCN opposite strand) is co-amplified with MYCN in pediatric cancers, including retinoblastoma. MYCNOS encodes several RNA variants whose functions have not been elucidated in retinoblastoma. Thus, we attempted to identify MYCNOS variants in retinoblastoma and aimed to decipher the role of MYCNOS variant 1 (MYCNOS1) on the activity of MYCN-amplified retinoblastoma.

Methods

The profiles of MYCNOS variants and MYCN status were determined in 17 retinoblastoma tissues, cell lines, retinas, and retinal organoids. A functional study of MYCNOS1 expression was conducted in patient-derived tumor cells and in retinoblastoma cell lines via short hairpin RNA-mediated gene silencing. We carried out MYCN expression, cell viability, cell cycle, apoptosis, soft agar colony formation, and transwell assays to examine the role of MYCNOS1 in MYCN and cell behaviors. We analyzed a transcriptome of MYCN-amplified retinoblastoma cells deficient for MYCNOS1 and, finally, tested the responses of these cells to chemotherapeutic agents.

Results

Expression of MYCNOS1 was associated with the expression and copy number of MYCN. Knockdown of MYCNOS1 caused instability of the MYCN protein, leading to cell cycle arrest and impaired proliferation and chemotaxis-directed migration in MYCN-amplified retinoblastoma cells in which RB1 was intact. MYCNOS1 expression was associated with gene signatures of photoreceptor cells and epithelial–mesenchymal transition. MYCNOS1 silencing enhanced the response of retinoblastoma cells to topotecan but not carboplatin.

Conclusions

MYCNOS1 supports progression of retinoblastoma. Inhibition of MYCNOS1 expression may be necessary to suppress MYCN activity when treating MYCN-amplified cancers without RB1 mutation.

Molecular Mechanisms of MYCN Dysregulation in Cancers

MYCN, a member of MYC proto-oncogene family, encodes a basic helix-loop-helix transcription factor N-MYC. Abnormal expression of N-MYC is correlated with high-risk cancers and poor prognosis. Initially identified as an amplified oncogene in neuroblastoma in 1983, the oncogenic effect of N-MYC is expanded to multiple neuronal and nonneuronal tumors. Direct targeting N-MYC remains challenge due to its "undruggable" features. Therefore, alternative therapeutic approaches for targeting MYCN-driven tumors have been focused on the disruption of transcription, translation, protein stability as well as synthetic lethality of MYCN. In this review, we summarize the latest advances in understanding the molecular mechanisms of MYCN dysregulation in cancers.

Wnt signalling pathway in bladder cancer

Bladder cancer (BC) is one of the most common tumours of the urinary system and is also known as a highly malignant tumour. In addition to conventional diagnosis and treatment methods, recent research has focused on studying the molecular mechanisms related to BC, in the hope that new, less toxic and effective targeted anticancer drugs and new diagnostic markers can be discovered. It is known that the Wingless (Wnt) signalling pathway and its related genes, proteins and other substances are involved in multiple biological processes of various tumours. Clarifying the contribution of the Wnt signalling pathway in bladder tumours will help establish early diagnosis indicators, develop new therapeutic drugs and evaluate the prognosis for BC. This review aims to summarise previous studies related to BC and the Wnt signalling pathway, with a focus on exploring the participating substances and their mechanisms in the regulation of the Wnt signalling pathway to better determine how to promote new chemotherapeutic drugs, potential therapeutic targets and diagnostic biomarkers.

Long non-coding RNA LSINCT5 inactivates Wnt/β-catenin pathway to regulate MCF-7 cell proliferation and motility through targeting the miR-30a

Background

Breast cancer (BC) is the most common malignant tumor among women. Earlier studies showed that long stress-induced non-coding transcript 5 (LSINCT5) was implicated in BC. However, the potential mechanisms of LSINCT5 in BC is still elusive.

Methods

Relative expression of LSINCT5 in BC tissues and cells were quantified by quantitative real-time reverse transcription PCR (qRT-PCR). shRNA was employed to specifically knockdown endogenous LSINCT5 in BC cells. Cell growth and invasion activity of BC cells was assessed by colony formation and transwell migration assay, respectively. The association between LSINCT5 and miR-30a was conducted by luciferase reporter assay. Subcutaneous injection of sh-LSINCT5 transfected MCF-7 cells into the ventral regions of mice to form tumors. Mice were divided into three groups (n=10): control group, sh-NC group, sh-LSINCT5 group (sh-NC or sh-LSINCT5 transfected MCF-7 cells injected into mice). Tumor weight was checked after 30 days post-injection.

Results

LSINCT5 was significantly up-regulated in BC tissues and cells. LSINCT5 knockdown suppressed proliferation, invasion, and epithelial-mesenchymal transition (EMT) in vitro and in vivo. LSINCT5 acted as a sponge molecule and targeted miR-30a in BC cells. Further mechanistic study exhibited that overexpression of LSINCT5 promoted the expression of Wnt/β-catenin-related proteins (β-catenin, TCF4, and c-Myc). In vivo, xenograft nude mice experiment indicated sh-LSINCT5 inhibited tumor growth and motility by targeting miR-30a through modulating Wnt/β-catenin pathway.

Conclusions

The present results uncovered that LSINCT5 knockdown suppressed BC growth and metastasis via the miR-30a/Wnt/β-catenin axis, and it served as a potential therapeutic target for early diagnosis and treatment of BC patients..

De novo evolved gene product NCYM in the pathogenesis and clinical outcome of human neuroblastomas and other cancers

NCYM is an antisense transcript of MYCN oncogene and promotes tumor progression. NCYM encodes a de novo protein whose open reading frame evolved from noncoding genomic regions in the ancestor of Homininae. Because of its topology, NCYM is always co-amplified with MYCN oncogene, and the mutual regulations between NCYM and MYCN maintain their expressions at high levels in MYCN-amplified tumors. NCYM stabilizes MYCN by inhibiting GSK3β, whereas MYCN stimulates transcription of both NCYM and MYCN. NCYM mRNA and its noncoding transcript variants MYCNOS have been shown to stimulate MYCN expression via direct binding to MYCN promoter, indicating that both coding and noncoding transcripts of NCYM induce MYCN expression. In contrast to the noncoding functions of NCYM, NCYM protein also promotes calpain-mediated cleavage of c-MYC. The cleaved product called Myc-nick inhibits cell death and promotes cancer cell migration. Furthermore, NCYM-mediated inhibition of GSK3β results in the stabilization of β-catenin, which promotes aggressiveness of bladder cancers. These MYCN-independent functions of NCYM showed their clinical significance in MYCN-non-amplified tumors, including adult tumors. This year is the 30th anniversary of the identification of NCYM/MYCNOS gene. On this special occasion, we summarize the current understanding of molecular functions and the clinical significance of NCYM and discuss future directions to achieve therapeutic strategies targeting NCYM.

Current advances of long non-coding RNAs mediated by wnt signaling in glioma

Glioma is the most common and aggressive brain tumor in the central nervous system (CNS), in which Wnt signaling pathway has been verified to play a pivotal role in regulating the initiation and progression. Currently, numerous studies have indicated that long non-coding RNAs (lncRNAs) have critical functions across biological processes including cell proliferation, colony formation, migration, invasion and apoptosis via Wnt signaling pathway in glioma. This review depicts canonical and non-canonical Wnt/β-catenin signaling pathway properties and relative processing mechanisms in gliomas, and summarizes the function and regulation of lncRNAs mediated by Wnt signaling pathway in the development and progression of glioma. Ultimately, we hope to seek out promising biomarkers and reliable therapeutic targets for glioma.

The multiple function of long noncoding RNAs in osteosarcoma progression, drug resistance and prognosis

Osteosarcoma is a bone tumor prevalent in children and young adults. LncRNAs are a family of non-protein-coding transcripts longer than 200 nucleotides. The tumor-related pathological functions of lncRNAs include proliferation, migration, and chemotherapy resistance, all of which have been widely acknowledged in research on osteosarcoma. In addition, compelling evidence suggests that lncRNAs could serve as diagnostic indicators, prognostic biomarkers, and targets for disease treatment. In this review, we systematically summarize how lncRNAs regulate tumorigenesis, invasion and therapeutic resistance. By deepening our knowledge of the relationship between lncRNAs and osteosarcoma, we hope to translate research findings into clinical applications as soon as possible.

Long non-coding RNA in bladder cancer

Bladder cancer (BC) is the ninth most common malignant disease and ranks fourteenth in cancer mortality worldwide. Moreover, among cancers, the incidence and mortality of BC in males increased to the 6th and 9th place, respectively. The overall survival (OS) declines dramatically as the cancer progresses, especially when urothelial cells transition from noninvasive to invasive. It is well known that epithelial cells can acquire invasive properties and a propensity to metastasize through the epithelial-to-mesenchymal transition (EMT) process in tumourigenesis and progression. However, the potential molecular mechanisms and key pathways are still unclear. As the sequencing technology advances, long non-coding RNAs (lncRNAs) have been proven to play an important role in regulating biological processes and cellular pathways. Here, we reviewed important lncRNAs, such as H19, UCA1 and MALAT1, that participate in the malignant phenotype of BC and regulate EMT signalling networks in the invasion-metastasis cascade during BC development. We further discuss MALAT1, PCAT-1 and SPRY4-IT1, and also urine and blood exosomal H19 and PTENP as potential noninvasive biomarkers. Moreover, antisense oligonucleotides (ASOs) and a double-stranded DNA plasmid (BC-819) have been designed for use in preclinical cancer models and clinical trials in patients. Therefore, the results of investigations have gradually prompted the utility of lncRNAs.

Vessel adherent growth represents a major challenge in the surgical resection of neuroblastoma and Is associated with adverse outcome

PURPOSE

Neuroblastoma (NB) is the most common extracranial, solid tumor in childhood, with a peak incidence in children under 6 years of age. Due to its variable course of disease, which ranges from spontaneous regression to metastatic spread, NB still represents a significant therapeutic challenge. Strikingly, a certain number of NBs intraoperatively show vessel adhesion and/or infiltrative growth, which is often not visible in pre-operative imaging. We proposed the term unexpected vessel infiltration of NB (UVIN) to denote this phenomenon. UVIN represents a major surgical challenge.

METHODS

In this study, we determined frequency and clinical relevance of UVIN in a cohort of 100 NB-patients with subsequent correlation to several unfavorable characteristics of disease. RNA expression levels of MYCN and its co-regulated antisense transcript MYCNOS to identify markers was measured by PCR.

RESULTS

We found UVIN to be present in 34% of cases and significantly correlated with incomplete resection, MYCN amplification, complications, neoadjuvant therapy, tumor grade and MYCNOS expression levels. MYCN expression levels showed no significant results with UVIN.

CONCLUSION

Collectively, our data show that UVIN represents a frequent surgical problem associated with a poor outcome in NB patients. MYCN and MYCNOS seem to be no appropriate markers for UVIN.

TYPE OF STUDY

Prognosis study.

LEVEL OF EVIDENCE

Level III.

Long noncoding RNA LSINCT5 promotes endometrial carcinoma cell proliferation, cycle, and invasion by promoting the Wnt/β-catenin signaling pathway via HMGA2

Background:

A review of the evidence has indicated the critical role of long noncoding RNA (lncRNA) LSINCT5 in a large number of human cancers. However, the mechanistic involvement of LSINCT5 in endometrial carcinoma (EC) is still unknown. Here the authors aim to characterize the expression status of LSINCT5 and elucidate its mechanistic relevance to EC.

Methods:

Relative expression of LSINCT5 and HMGA2 were quantified by a real-time polymerase chain reaction. SiRNAs were employed to specifically knockdown endogenous LSINCT5 in EC cells. Cell proliferation was measured with Cell Count Kit-8 kit (CCK-8, Dojindo, Kumamoto, Japan) and cell growth was assessed by a colony formation assay. The cell cycle was analyzed with propidium iodide (PI) staining. Apoptotic cells were determined by flow cytometry after Annexin V/PI double-staining. Cell migration was evaluated by a wound-healing assay, and cell invasion was assessed using a transwell migration assay. The protein levels of HMGA2, Wnt3a, p-β-catenin, c-myc, β-actin, and GAPDH were determined by western blot.

Results:

The authors observed positively correlated and aberrantly up-regulated LSINCT5 and HMGA2 in EC. LSINCT5 deficiency significantly inhibited cell proliferation, cell cycle progression, and induced apoptosis. Meanwhile, cell migration and invasion were greatly compromised by the LSINCT5 knockdown. LSINCT5 stabilized HMGA2, which subsequently stimulated activation of Wnt/β-catenin signaling and consequently contributed to the oncogenic properties of LSINCT5 in EC.

Conclusions:

Our data uncovered the oncogenic activities and highlighted the mechanistic contributions of the LSINCT5-HMGA2-Wnt/β-catenin signaling pathway in EC.

An eight-long non-coding RNA signature as a candidate prognostic biomarker for bladder cancer

Backgroud: Bladder cancer (BLCA) is one of the most fatal types of cancer worldwide. However, there are limited methods for us to provide a prognostic prediction of BLCA patients. Therefore, we aimed at developing a lncRNA signature to improve the prognosis prediction of BLCA.

RESULTS

An eight-lncRNA signature was significantly associated with recurrence free survival in BLCA patients from both discovery and validation groups. Furthermore, genes involved in the signature were enriched in extracellular matrix organization pathway. Finally, functional experiments demonstrated that six out of the eight lncRNAs significantly regulated the invasion of BLCA cells.

METHOD

A total of 343 BLCA patients from The Cancer Genome Atlas (TCGA) were employed and randomly divided into training (n=172) and validating (n=171) groups. The lncRNA expression profiles of BLCA patients were screened and a risk-score formula were created and validated according to the Cox regression analysis. Next, WGCNA method was employed to cluster genes that highly correlated with the risk scores based on the profiling data of TCGA dataset and transwell assay was also performed to further investigate the role of these lncRNAs.

CONCLUSIONS

Our results suggested that the eight-lncRNA signature was a candidate prognostic biomarker for predicting tumor recurrence of patients with BLCA.

YY1-Induced Upregulation of Long Noncoding RNA ARAP1-AS1 Promotes Cell Migration and Invasion in Colorectal Cancer Through the Wnt/β-Catenin Signaling Pathway

Introduction: It has been reported that long noncoding RNAs (lncRNAs) are crucial regulators in progression of human cancers, including colorectal cancer (CRC). However, the function of lncRNA ARAP1 antisense RNA 1 (ARAP1-AS1) in CRC remains unclear. Aim: The aim of this study was to investigate the function and molecular mechanism of lncRNA ARAP1-AS1 in CRC. Results: ARAP1-AS1 was highly expressed in CRC tissues and cell lines. ARAP1-AS1 knockdown suppressed cell migration, invasion, and epithelial-mesenchymal transition (EMT). YY1 transcription factor (YY1) enhanced the transcription activity of ARAP1-AS1. The YY1/ARAP1-AS1 axis promoted CRC cell migration and invasion. YY1/ARAP1-AS1 could regulate the Wnt/β-catenin signaling pathway. Conclusions: This study revealed that YY1-induced upregulation of ARAP1-AS1 promoted cell migration, invasion, and EMT process in CRC through the Wnt/β-catenin signaling pathway.

LSINCT5 predicts unfavorable prognosis and exerts oncogenic function in osteosarcoma

The dysregulated expression of LSINCT5 (long stress-induced non-coding transcript 5) has been found in various human tumors, and was generally related to cancer progression and unfavorable prognosis. Although the role of LSINCT5 in osteosarcoma was reported not long ago, the sample size of that study was limited. Our study presented more evidence about the clinical significance and biological function of LSINCT5 in osteosarcoma. In our results, we found LSINCT5 expression was increased in osteosarcoma tissue samples and cell lines, and high LSINCT5 expression was associated with advanced Enneking stage, large tumor size, high histological grade and present distant metastasis. Meanwhile, we observed high LSINCT5 expression was correlated with worse overall survival, and high LSINCT5 expression could be an independent poor predictor for overall survival in osteosarcoma cases. Moreover, we found inhibition of LSINCT5 expression suppressed cell proliferation, migration and invasion in vitro, and LSINCT5 overexpression dramatically facilitated cell proliferation, migration and invasion in vitro. In conclusion, our study suggests that LSINCT5 exerts oncogenic function in osteosarcoma cells, and may be a potential predictor for clinical outcome in osteosarcoma patients.

Higher Expression of Linc00152 Promotes Bladder Cancer Proliferation and Metastasis by Activating the Wnt/β-Catenin Signaling Pathway

BACKGROUND Recent studies have demonstrated that Linc00152 is highly expressed in multiple cancer types and its genes show tumor-promoting characteristics. However, the efficacy and biological mechanism of Linc00152 in bladder cancer remains unclear. MATERIAL AND METHODS We study investigated the relative expression and promoter methylation of Linc00152 in 126 cases of bladder cancer tissues by qRT-PCR and Bisulfite sequencing PCR. qRT-PCR was used to assess the relative expression of Linc00152 in 4 human bladder cancer cell lines. To explore the biological properties of Linc00152, we performed cell growth and soft-agar colony-formation assays, flow cytometry analyses, wound-healing assay, and Transwell assay. Western blot analysis was used to detect the underlying mechanisms of Linc00152 in bladder cancer. RESULTS We found that Linc00152 was highly expressed in 126 cases of bladder carcinoma tissues (p<0.001) and 4 cell lines (p<0.01), and Linc00152 is more commonly expressed in patients with advanced-stage cancer (p=0.021). Knockdown of Linc00152 by using siRNAs in bladder cancer cell lines (T24 and HT-1197) suppressed cell viability and growth by causing cell cycle arrest and apoptosis (p<0.001), as well as inhibiting cell migration and invasion (p<0.001). In addition, the quantitative RT-PCR and Western blot results suggest that knockdown of Linc00152 reduced Wnt/ß-Catenin signaling (p<0.001). CONCLUSIONS This research shows that Linc00152 is highly expressed in patients with bladder cancer and the possible carcinogenic effect of Linc00152 in bladder cancer occurs through activating the Wnt/ß-Catenin signaling pathway, and could be a new biomarker for diagnosis and prevention of this cancer.

LncRNA GAS6-AS2 promotes bladder cancer proliferation and metastasis via GAS6-AS2/miR-298/CDK9 axis

Long noncoding RNAs (lncRNAs) have been proved to play important roles in carcinogenesis and development of numerous cancers, but their biological functions in bladder cancer remain largely unknown. In this study, a novel lncRNA termed GAS6‐AS2 were primary identified, and its roles as well as mechanisms in regulating proliferation and metastasis of bladder cancer cells were investigated. Clinically, GAS6‐AS2 was significantly up‐regulated in bladder cancer tissues and positively correlated with tumour stages and poor prognosis. Moreover, expression of GAS6‐AS2 was also increased in bladder cancer cells compared with normal bladder cells. Further investigating the roles of GAS6‐AS2, we found GAS6‐AS2 regulated proliferation and proliferative activity of bladder cancer cells via inducing G1 phase arrest. What's more, we found that GAS6‐AS2 contributed to metastatic abilities of cells. In mechanism, GAS6‐AS2 could function as a competitive endogenous RNA (ceRNA) via direct sponging miR‐298, which further regulating the expression of CDK9. Finally, we also proved that GAS6‐AS2 knockdown suppressed tumour growth and metastasis in vivo. In conclusion, our study proved that GAS6‐AS2 could function as a ceRNA and promote the proliferation and metastasis of bladder cancer cells, which provided a novel prognostic marker for bladder cancer patients in clinic.

LncRNA LINC00641 predicts prognosis and inhibits bladder cancer progression through miR-197-3p/KLF10/PTEN/PI3K/AKT cascade

As a new group of important effector molecules involved in multiple cancers, long noncoding RNAs (lncRNAs) have attracted much attention recently. Especially, evidences have indicated lncRNAs might be promising biomarkers and targets for cancer therapy. LINC00641 is a novel lncRNA, whose function remains totally unclear. The aim of our study was to determine the functions of LINC00641 in bladder cancer. We found that LINC00641 expression was significantly down-regulated in bladder cancer tissues. Down-regulation of LINC00641 in patients with bladder cancer predicts poor prognosis. Gain-of-function assays indicated that LINC00641 up-regulation markedly inhibited the proliferation, migration and invasion of bladder cancer cells. Xenograft assay also confirmed that LINC00641 overexpression suppressed bladder cancer growth in vivo. Mechanistically, LINC00641 was demonstrated to interact with miR-197-3p, whose target was KLF10. By up-regulating KLF10 level, LINC00641 suppressed the PTEN/PI3K/AKT pathway, leading to prevention of bladder cancer progression. Taken together, our study illustrated a novel signaling cascade of LINC00641/miR-197-3p/KLF10/PTEN/PI3K/AKT pathway regulating bladder cancer development.