The putative oncogene, CRNDE, is a negative prognostic factor in ovarian cancer patients

The Clinical Significance of CRNDE Gene Methylation, Polymorphisms, and CRNDEP Micropeptide Expression in Ovarian Tumors

CRNDE is an oncogene expressed as a long non-coding RNA. However, our team previously reported that the CRNDE gene also encodes a micropeptide, CRNDEP. The amino acid sequence of CRNDEP has recently been revealed by other researchers, too. This study aimed to investigate genetic alterations within the CRNDEP-coding region of the CRNDE gene, methylation profiling of this gene, and CRNDEP expression analysis. All investigations were performed on clinical material from patients with ovarian tumors of diverse aggressiveness. We found that CRNDEP levels were significantly elevated in highly aggressive tumors compared to benign neoplasms. Consistently, a high level of this micropeptide was a negative, independent, prognostic, and predictive factor in high-grade ovarian cancer (hgOvCa) patients. The cancer-promoting role of CRNDE(P), shown in our recent study, was also supported by genetic and epigenetic results obtained herein, revealing no CRNDEP-disrupting mutations in any clinical sample. Moreover, in borderline ovarian tumors (BOTS), but not in ovarian cancers, the presence of a single nucleotide polymorphism in CRNDE, rs115515594, significantly increased the risk of recurrence. Consistently, in BOTS only, the same genetic variant was highly overrepresented compared to healthy individuals. We also discovered that hypomethylation of CRNDE is associated with increased aggressiveness of ovarian tumors. Accordingly, hypomethylation of this gene's promoter/first exon correlated with hgOvCa resistance to chemotherapy, but only in specimens with accumulation of the TP53 tumor suppressor protein. Taken together, these results contribute to a better understanding of the role of CRNDE(P) in tumorigenesis and potentially may lead to improvements in screening, diagnosis, and treatment of ovarian neoplasms.

A Multi-Faceted Analysis Showing CRNDE Transcripts and a Recently Confirmed Micropeptide as Important Players in Ovarian Carcinogenesis

CRNDE is considered an oncogene expressed as long non-coding RNA. Our previous paper is the only one reporting CRNDE as a micropeptide-coding gene. The amino acid sequence of this micropeptide (CRNDEP) has recently been confirmed by other researchers. This study aimed at providing a mass spectrometry (MS)-based validation of the CRNDEP sequence and an investigation of how the differential expression of CRNDE(P) influences the metabolism and chemoresistance of ovarian cancer (OvCa) cells. We also assessed cellular localization changes of CRNDEP, looked for its protein partners, and bioinformatically evaluated its RNA-binding capacities. Herein, we detected most of the CRNDEP sequence by MS. Moreover, our results corroborated the oncogenic role of CRNDE, portraying it as the gene impacting carcinogenesis at the stages of DNA transcription and replication, affecting the RNA metabolism, and stimulating the cell cycle progression and proliferation, with CRNDEP being detected in the centrosomes of dividing cells. We also showed that CRNDEP is located in nucleoli and revealed interactions of this micropeptide with p54, an RNA helicase. Additionally, we proved that high CRNDE(P) expression increases the resistance of OvCa cells to treatment with microtubule-targeted cytostatics. Furthermore, altered CRNDE(P) expression affected the activity of the microtubular cytoskeleton and the formation of focal adhesion plaques. Finally, according to our in silico analyses, CRNDEP is likely capable of RNA binding. All these results contribute to a better understanding of the CRNDE(P) role in OvCa biology, which may potentially improve the screening, diagnosis, and treatment of this disease.

A comprehensive review of lncRNA CRNDE in cancer progression and pathology, with a specific glance at the epithelial-mesenchymal transition (EMT) process

It has been suggested that the long non-coding RNAs (lncRNAs), such as colorectal neoplasia differentially expressed (CRNDE), may contribute to the formation of human cancer. It is yet unknown, though, what therapeutic significance CRNDE expression has for different forms of cancer. CRNDE has recently been proposed as a possible diagnostic biomarker and prognostic pred for excellent specificity and sensitivity in cancer tissues and plasma. To provide the groundwork for potential future therapeutic uses of CRNDE, we briefly overview its biological action and related cancer-related pathways. Next, we mainly address the impact of CRNDE on the epithelial-mesenchymal transition (EMT). The epithelial-mesenchymal transition, or EMT, is an essential biological mechanism involved in the spread of cancer.

Contribution of CRNDE lncRNA in the development of cancer and the underlying mechanisms

Colorectal Neoplasia Differentially Expressed (CRNDE) is an lncRNA with crucial roles in cancer development. It is located on chromosome 16 on the opposite strand to the adjacent IRX5 gene, implying the presence of a shared bidirectional promoter for these two genes. Expression of CRNDE has been assessed in a diverse array of hematological malignancies and solid tumors, representing its potential as a therapeutic target in these conditions. This lncRNA has a regulatory effect on activity of several pathways and axes that are involved in the regulation of cell apoptosis, immune responses and tumorigenesis. The current review is an updated review about the role of CRNDE in the development of cancers.

LncRNA CRNDE promotes cell proliferation, migration and invasion of ovarian cancer via miR-423-5p/FSCN1 axis

Ovarian cancer seriously threatens the health of women. LncRNA CRNDE is known to be upregulated in ovarian cancer. However, the mechanism by which CRNDE regulates the progress of ovarian cancer is largely unknown. MTT assay was applied to measure the cell viability. Colony formation assay was used to measure the cell proliferation. Cell migration was tested by wound healing, and Transwell assay was performed to detect cell invasion. In addition, the expression of miR-423-5p, CRNDE and FSCN1 were detected by RT-qPCR and western blotting, respectively. Meanwhile, dual-luciferase reporter assay and RIP assay were performed to explore the correlation between miR-423-5p and CRNDE (or FSCN1). CRNDE and FSCN1 were upregulated in ovarian cancer cells (SKOV3, CAOV-3, IGROV1, A2780 and C13K), while miR-423-5p was downregulated. Moreover, silencing of FSCN1/CRNDE significantly decreased proliferation, migration and invasion of ovarian cancer cells (SKOV3 and CI3K) via suppressing MMP-2 and MMP-9. In addition, CRNDE could sponge miR-423-5p, and FSCN1 was confirmed to be the direct target of miR-423-5p. Furthermore, CRNDE knockdown-induced inhibition of FSCN1 was notably reversed by miR-423-5p downregulation. Knockdown of CRNDE inhibited cell proliferation, migration and invasion of ovarian cancer via miR-423-5p/FSCN1 axis. Thus, CRNDE may serve a new target for ovarian cancer.

Long Noncoding RNA CRNDE Functions as an Oncogene to Facilitate Aggressive Behaviors of Nasopharyngeal Carcinoma Cells by Modulating miR-3163/TWIST1 Axis

Long noncoding RNA (lncRNA) CRNDE has been broadly implicated in many malignancies. The aim of this study was to explore the function and potential mechanisms of CRNDE in nasopharyngeal carcinoma (NPC). Here, we discovered that CRNDE level was increased in NPC tissues and cell lines. Additionally, elevated CRNDE positively correlated with large tumor size, advanced TNM stage, distant metastasis, EBV infection and worse prognosis. Furthermore, depletion of CRNDE significantly impaired the capacity of proliferation, migration and invasion in NPC cells. Mechanically, CRNDE could serve as a molecular sponge of miR-3163 to regulate the expression of TWIST1. Importantly, the inhibitory effects of CRNDE knockdown on cell proliferation and metastasis were blocked by silence of miR-3163 or restoration of TWIST1 expression. Overall, our data highlighted that CRNDE could promote NPC progression via altering miR-3163/TWIST1 axis, suggesting CRNDE as a potential prognostic biomarker and therapeutic target for NPC treatment.

A New Light on Potential Therapeutic Targets for Colorectal Cancer Treatment

The development and progression of colorectal cancer (CRC) involve changes in genetic and epigenetic levels of oncogenes and/or tumor suppressors. In spite of advances in understanding of the molecular mechanisms involved in CRC, the overall survival rate of CRC still remains relatively low. Thus, more research is needed to discover and investigate effective biomarkers and targets for diagnosing and treating CRC. The roles of long non-coding RNAs (lncRNAs) participating in various aspects of cell biology have been investigated and potentially contribute to tumor development. Our recent study also showed that CRNDE was among the top 20 upregulated genes in CRC clinical tissues compared to normal colorectal tissues by analyzing a Gene Expression Omnibus (GEO) dataset (GSE21815). Although CRNDE is widely reported to be associated with different types of cancer, most studies of CRNDE were limited to examining regulation of its transcription levels, and in-depth mechanistic research is lacking. In the present study, CRNDE was found to be significantly upregulated in CRC patients at an advanced TNM stage, and its high expression was correlated with poor outcomes of CRC patients. In addition, we found that knocking down CRNDE could reduce lipid accumulation through the miR-29b-3p/ANGPTL4 axis and consequently induce autophagy of CRC cells.

Research Progress in Prognostic Factors and Biomarkers of Ovarian Cancer

Ovarian cancer is a serious threat to women's health; its early diagnosis rate is low and prone to metastasis and recurrence. The current conventional treatment for ovarian cancer is a combination of platinum and paclitaxel chemotherapy based on surgery. The recurrence and progression of ovarian cancer with poor prognosis is a major challenge in treatment. With rapid advances in technology, understanding of the molecular pathways involved in ovarian cancer recurrence and progression has increased, biomarker-guided treatment options can greatly improve the prognosis of patients. This review systematically discusses and summarizes existing and new information on prognostic factors and biomarkers of ovarian cancer, which is expected to improve the clinical management of patients and lead to effective personalized treatment.

Knockdown of LncRNA CRNDE suppresses proliferation and P-glycoprotein-mediated multidrug resistance in acute myelocytic leukemia through the Wnt/β-catenin pathway

Mechanisms involved in non-coding RNAs have been implicated in multidrug resistance (MDR) of acute myeloid leukemia (AML). Long non-coding RNA (lncRNAs) colorectal neoplasia differentially expressed (CRNDE) is reported to be involved in the malignant progression in AML. The purpose of the present study is to explore the roles and potential molecular mechanism of CRNDE in the MDR in AML. In our study, we confirmed that the expression of CRNDE was significantly up-regulated in patients with AML, especially in AML patients after adriamycin (ADR)-based chemotherapy. Spearman correlation analysis showed a positive correlation between the levels of CRNDE and MDR1 in AML patients after ADR-based chemotherapy. Moreover, CRNDE was up-regulated in AML cells, especially in ADR-resistant AML cells. Multidrug resistance protein 1 (MDR1)/p-glycoprotein (P-gp) levels were significantly increased in ADR-resistant AML cells, compared with parental AML cells. CRNDE down-regulation inhibited cell proliferation, promoted apoptosis, reduced Ki67 expression and enhanced cleaved caspase-3 expression in AML and ADR-resistant AML cells. In addition, CRNDE knockdown led to down-regulation of P-gp/MDR1, β-catenin, c-Myc and cyclinD1 expression, and enhanced the drug sensitivity to ADR in ADR-resistant AML cells. In conclusion, knockdown of CRNDE suppresses proliferation and P-gp-mediated MDR in ADR-resistant AML cells via inhibiting the Wnt/β-catenin pathway, suggesting that repression of CRNDE might be a therapeutic target to reverse MDR of ADR-resistant AML cells.

ceRNA Network Analysis Shows That lncRNA CRNDE Promotes Progression of Glioblastoma Through Sponge mir-9-5p

Glioblastoma accounts for 45.2% of central nervous system tumors. Despite the availability of multiple treatments (e.g., surgery, radiotherapy, chemotherapy, biological therapy, immunotherapy, and electric field therapy), glioblastoma has a poor prognosis, with a 5-year survival rate of approximately 5%. The pathogenesis and prognostic markers of this cancer are currently unclear. To this end, this study aimed to explore the pathogenesis of glioblastoma and identify potential prognostic markers. We used data from the GEO and TCGA databases and identified five genes (ITGA5, MMP9, PTPRN, PTX3, and STX1A) that could affect the survival rate of glioblastoma patients and that were differentially expressed between glioblastoma patients and non-tumors groups. Based on a variety of bioinformatics tools for reverse prediction of target genes associated with the prognosis of GBM, a ceRNA network of messenger RNA (STX1A, PTX3, MMP9)-microRNA (miR-9-5p)-long non-coding RNA (CRNDE) was constructed. Finally, we identified five potential therapeutic drugs (bacitracin, hecogenin, clemizole, chrysin, and gibberellic acid) that may be effective treatments for glioblastoma.

The role of altered long noncoding RNAs in overall survival of ovarian cancer: A systematic review and meta-analysis

In recent years, tremendous research efforts have been focused on investigating the effect of dysregulation of lncRNAs on cancer progression, most of which confirm a positive link. This inspired us to conduct the present meta-analysis to explore whether aberrant expression of multiple lncRNAs has a role in patients' outcome in ovarian cancer. This comprehensive meta-analysis pertains to the evaluation of association between dysregulated lncRNAs expression level with eventual outcome and clinicopathological characteristics of ovarian cancer patients. We systematically searched PubMed, Web of Science, and Scopus to find all eligible articles. Pooled hazard ratios (HRs) and 95% confidence intervals (95% CIs) for overall survival, disease-free survival and progression-free survival were measured with a fixed or random effects model. A total of 34 studies were included in the meta-analysis. Dysregulation of lncRNAs were contributed to shorter overall survival (34 studies, 1180 patients HR = 2.12, 95% CI: 1.73 ± 2.60, random-effects) in ovarian cancer. Furthermore, altered lncRNAs were also related to decreased progression-free survival (8 studies, 1180 patients HR: 1.88, 95% CI: (1.35-2.62) and disease-free survival (2 studies, 285 patients, HR: 6.07, 95% CI: 1.28-28.78) in this disease. Our analyses supported the robust prognostic significance of altered lncRNAs in ovarian cancer. However, more extended studies are encouraged to evaluate the clinical application potential of these lncRNAs in the prognosis evaluation of ovarian cancer.

LncRNA CRNDE acts as an oncogene in cervical cancer through sponging miR-183 to regulate CCNB1 expression

Studies have identified a series of lncRNAs that contributed to various tumors, although the underlying mechanisms remain largely unclear. We proposed a ceRNA network and investigate relations among lncRNA/miRNA/mRNA in cervical cancer (CC). The genes of differential expression and lncRNA/miRNA/mRNA network were identified by combining TCGA, miRcode, starBase, miRTarBase, miRDB, TargetScan and STRING databases. Meanwhile, the function enrichment was recognized with Gene Ontology and Kyoto Encyclopedia of Genes and Genomes. Quantitative real time-PCR (qRT-PCR) was performed to determine colorectal neoplasia differentially expressed (CRNDE) expression in CC tissues and cell lines. The effects of CRNDE on the CC biological functions and cyclin B1 (CCNB1) expression were detected by conducting in vitro and in vivo experiments. Quantitative real time-PCR, western blot and dual-luciferase reporter assay were used to predict the target of miR-183. Furthermore, rescue experiments were conducted to further confirm the regulation of CCNB1 by CRNDE. Systematic analyses of bioinformatics from several databases predicted that CRNDE, miR-183 and CCNB1 were in the same network path. Their expressions were up-regulated in CC tissues and cells. Silencing CRNDE-inhibited cell proliferation, migration and invasion, restricted solid tumor growth and promoted cell apoptosis. Moreover, our results suggested that miR-183 targeted the CCNB1 3'UTR and regulated its expression. Additionally, miR-183 mimic could inverse the antitumor function of CRNDE inhibition and partially eliminated the attenuated expression of CCNB1 induced by silencing CRNDE, indicating that CRNDE could positively regulate CCNB1 expression by sponging miR-183. Our study highlighted a role for the CRNDE/miR-183/CCNB1-axis in CC and offered a promising diagnostic strategy for CC treatment.

Coding of Glioblastoma Progression and Therapy Resistance through Long Noncoding RNAs

Glioblastoma is the most aggressive and lethal primary brain malignancy, with an average patient survival from diagnosis of 14 months. Glioblastoma also usually progresses as a more invasive phenotype after initial treatment. A major step forward in our understanding of the nature of glioblastoma was achieved with large-scale expression analysis. However, due to genomic complexity and heterogeneity, transcriptomics alone is not enough to define the glioblastoma “fingerprint”, so epigenetic mechanisms are being examined, including the noncoding genome. On the basis of their tissue specificity, long noncoding RNAs (lncRNAs) are being explored as new diagnostic and therapeutic targets. In addition, growing evidence indicates that lncRNAs have various roles in resistance to glioblastoma therapies (e.g., MALAT1, H19) and in glioblastoma progression (e.g., CRNDE, HOTAIRM1, ASLNC22381, ASLNC20819). Investigations have also focused on the prognostic value of lncRNAs, as well as the definition of the molecular signatures of glioma, to provide more precise tumor classification. This review discusses the potential that lncRNAs hold for the development of novel diagnostic and, hopefully, therapeutic targets that can contribute to prolonged survival and improved quality of life for patients with glioblastoma.

CRNDE: an oncogenic long non-coding RNA in cancers

Colorectal neoplasia differentially expressed (CRNDE) is a long non-coding RNA which has been proved upregulated in various cancers. Meanwhile, CRNDE has been demonstrated to be involved in multiple biological processes of different cancers according to previous study. Moreover, recent studies suggested CRNDE might be a potential diagnostic biomarker and prognostic predictor due to its high sensitivity and specificity in cancer tissues and plasma. In this review, we summarize the biological function of CRNDE and the relevant mechanisms in cancers to establish a molecular basis for the clinical use of CRNDE in the future.

Effects and Mechanism of lncRNA CRNDE on Sepsis-Induced Acute Kidney Injury

Objective

To investigate the effects of lncRNA CRNDE on sepsis-associated acute kidney injury in the human kidney 2 cell line and explore the potential mechanisms.

Methods

HK-2 cells were treated with lipopolysaccharides to induce injuries. The expression of CRNDE and miR-146a in HK-2 cells were altered by a transient transfection assay. Cell apoptosis was detected by a flow cytometry assay, and the levels of inflammatory cytokines including TNF-α, IL-6, IL-8, and IL-1β were assessed by ELISA. Furthermore, western blot analysis was performed to detect the expression levels of TLR4/NF-κB pathway-related proteins. And a luciferase reporter gene assay was used to verify if miR-146a was the target of CRNDE.

Results

LPS treatment increased CRNDE expression in HK-2 cells. CRNDE overexpression enhanced cell injuries in HK-2 cells significantly increasing inflammatory cytokine levels, including TNF-α, IL-6, IL-8, and IL-1β, and cell apoptosis. In addition, CRNDE overexpression further activated the TLR4/NF-κB pathways in HK-2 cells. Inversely, opposite results were observed in the miR-146a mimic treatment group, and the miR-146a inhibitor could reverse the protein expression changes of TLR4/NF-κB in the si-CRNDE and LPS treatment group.

Conclusion

This study demonstrated that CRNDE overexpression could activate the TLR4/NF-κB signaling pathway by regulating miR-146a, which accelerated LPS-induced inflammation and apoptosis in HK-2 cells.

Long Non-coding RNAs Involved in Resistance to Chemotherapy in Ovarian Cancer

Ovarian cancer (OC) accounts for more than 150,000 deaths worldwide every year. Patients are often diagnosed at an advanced stage with metastatic dissemination. Although platinum- and taxane-based chemotherapies are effective treatment options, they are rarely curative and eventually, the disease will progress due to acquired resistance. Emerging evidence suggests a crucial role of long non-coding RNAs (lncRNAs) in the response to therapy in OC. Transcriptome profiling studies using high throughput approaches have identified differential expression patterns of lncRNAs associated with disease recurrence. Furthermore, several aberrantly expressed lncRNAs in resistant OC cells have been related to increased cell division, improved DNA repair, up-regulation of drug transporters or reduced susceptibility to apoptotic stimuli, supporting their involvement in acquired resistance. In this review, we will discuss the key aspects of lncRNAs associated with the development of resistance to platinum- and taxane-based chemotherapy in OC. The molecular landscape of OC will be introduced, to provide a background for understanding the role of lncRNAs in the acquisition of malignant properties. We will focus on the interplay between lncRNAs and molecular pathways affecting drug response to evaluate their impact on treatment resistance. Additionally, we will discuss the prospects of using lncRNAs as biomarkers or targets for precision medicine in OC. Although there is still plenty to learn about lncRNAs and technical challenges to be solved, the evidence of their involvement in OC and the development of acquired resistance are compelling and warrant further investigation for clinical applications.

LncRNA CRNDE regulates trophoblast cell proliferation, invasion, and migration via modulating miR-1277

Preeclampsia (PE) is a pregnancy-specific syndrome and contributes to maternal and perinatal morbidity and mortality, but the underlying mechanisms of PE remain indistinct. This study aims to investigate the functional role of LncRNA CRNDE in PE pathogenesis and its effects on trophoblasts. mRNA levels of CRNDE and miR-1277 in placenta tissues and HTR-8/SVneo cells were analyzed by qRT-PCR. Western blot was carried out to evaluate protein level of E-cadherin, β-Catenin, Vimentin, MMP2 and MMP9. Cell proliferation was assessed by using CCK-8 assay and colony formation assay, whereas cell migration and invasion were evaluated by wound healing assay and transwell assay, respectively. Moreover, the interrelation between CRNDE and miR-1277 was verified by dual luciferase reporter assay. The results showed that CRNDE expression was significantly downregulated, whereas miR-1277 expression was significantly upregulated in PE placental tissues. Overexpression of CRNDE facilitated HTR-8/SVneo cell proliferation, migration and invasion, promoted the EMT formation, and increased the protein expression of MMP2 and MMP9, while knockdown of CRNDE had the opposite results. In addition, we also found that miR-1277 was negatively regulated by CRNDE and was a direct target of CRNDE. Furthermore, knockdown of miR-217 promoted HTR-8/SVneo cell proliferation, migration, and invasion, while knockdown of CRNDE reversed the accelerating effects of miR-1277 on HTR-8/SVneo cells. LncRNA CRNDE may suppress trophoblast cell proliferation, migration and invasion at least partly through regulating miR-1277 in trophoblast cells. CRNDE is promising to function as a new target for intervention of PE.

Prognostic Value of Long Noncoding RNA CRNDE as a Novel Biomarker in Solid Cancers: An Updated Systematic Review and Meta-Analysis

Background: Long noncoding RNA colorectal neoplasia differentially expressed (CRNDE) has been reported to exhibit a potential oncogenic role in the development of human cancers. However, the clinical value of CRNDE expression in various cancers still remains unclear. Herein, we conducted a meta-analysis to investigate the association between CRNDE and clinical outcomes in solid cancers.

Methods: A systematic search was performed though the PubMed, EMBASE, Web of Science, Ovid, Cochrane library, CNKI and WanFang databases for eligible studies on clinical values of CRNDE in solid cancers. The pooled hazard ratios (HRs) or odd ratios (ORs) with 95% confidence intervals (CIs) were used to evaluate the link between CRNDE and clinical outcomes.

Results: A total of 3690 patients from 20 studies (including 2 studies have 2 cohorts, respectively) were included. The results suggested that elevated CRNDE expression predicted a poor overall survival (OS) for in 13 types of solid cancers (HR=1.46, 95% CI: 1.33-1.58, P<0.001) with no heterogeneity (I²=21.8%, P=0.19). Subgroup analysis indicated a significant association between high CRNDE expression and shorter OS in the studies with digestive system cancers (HR=1.42, 95% CI: 1.28-1.55, P<0.001), qRT-PCR method (HR=1.45, 95% CI: 1.30-1.59, P<0.001), sample size >100 (HR=1.44, 95% CI: 1.32-1.57, P<0.001), and NOS>7 (HR= 1.50, 95% CI: 1.23-1.78, P<0.001). Furthermore, the pooled results showed that CRNDE was an independent prognostic factor for OS in cancer patients (HR=1.37, 95% CI: 1.22-1.52, P<0.001). In addition, we also revealed that CRNDE was positively related to tumor size (OR=2.10, 95%CI: 1.68-2.63, P<0.001), TNM stage (OR=2.86, 95%CI: 2.29-3.56, P<0.001), lymph node metastasis (LNM) (OR=3.21, 95%CI: 2.01-5.13, P<0.001), and distant metastasis (OR=4.36, 95%CI: 2.36-8.07, P<0.001). Although the probable evidences of publication bias were found in the studies with OS, tumor size, TNM stage or LNM, the trim and fill analysis confirmed the reliability of these results was not affected.

Conclusion: Elevated CRNDE expression was associated with larger tumor size, advanced TNM stage, worse LNM and distant metastasis, and shorter OS, suggesting that CRNDE may act as an independent prognostic biomarker in solid cancers.

CRNDE enhances neuropathic pain via modulating miR-136/IL6R axis in CCI rat models

Neuropathic pain has been reported as a type of chronic pain due to the primary dysfunction of the somatosensory nervous system. It is the most serious types of chronic pain, which can lead to a significant public health burden. But, the understanding of the cellular and molecular pathogenesis of neuropathic pain is barely complete. Long noncoding RNAs (lncRNAs) have recently been regarded as modulators of neuronal functions. Growing studies have indicated lncRNAs can exert crucial roles in the development of neuropathic pain. Therefore, our present study focused on the potential role of the lncRNA Colorectal Neoplasia Differentially Expressed (CRNDE) in neuropathic pain progression. Firstly, a chronic constrictive injury (CCI) rat model was built. CRNDE was obviously increased in CCI rats. Interestingly, overexpression of CRNDE enhanced neuropathic pain behaviors. Neuroinflammation was induced by CRNDE and as demonstrated, interleukin-10 (IL-10), IL-1, IL-6, and tumor necrosis factor-α (TNF-α) protein levels in CCI rats were activated by LV-CRNDE. For another, miR-136 was obviously reduced in CCI rats. Previously, it is indicated that miR-136 participates in the spinal cord injury via an inflammation in a rat model. Here, firstly, we verified miR-136 could serve as CRNDE target. Loss of miR-136 triggered neuropathic pain remarkably via the neuroinflammation activation. Additionally, IL6R was indicated as a target of miR-136 and miR-136 regulated its expression. Subsequently, we confirmed that CRNDE could induce interleukin 6 receptor (IL6R) expression positively. Overall, it was implied that CRNDE promoted neuropathic pain progression via modulating miR-136/IL6R axis in CCI rat models.

Long non-coding RNA CRNDE regulates cell proliferation, migration, invasion, epithelial-mesenchymal transition and apoptosis in oral squamous cell carcinoma

The present study aimed to investigate whether the long non-coding RNA (lncRNA) colorectal neoplasia differentially expressed (CRNDE) can promote the migration and invasion of human oral squamous cell carcinoma (OSCC) cells via the regulation of epithelial-mesenchymal transition (EMT). CAL-27 and SCC-15 cells were classified into a control group, a small interfering negative control (si-NC) group (cells transfected with control siRNA) and an si-CRNDE group (cells transfected with CRNDE siRNA). The expression of CRNDE in OSCC tissues and cell lines was detected by in situ hybridization (ISH) and reverse transcription-quantitative polymerase chain reaction. An MTT assay was used to detect cell proliferation, flow cytometry was performed to determine cell apoptosis, wound-healing and Transwell assays were conducted to evaluate cell metastasis, and immunofluorescence staining and western blotting were performed to measure the expression of proteins associated with EMT. Tumor-bearing mouse models were established, and the tumor volumes were recorded. An immunohistochemical assay was performed to determine the expression of EMT-related proteins. CRNDE expression was increased in OSCC tissues and cell lines compared with that in normal tissues and cell lines. Compared with the control group, the si-CRNDE group displayed a reduction in the expression of CRNDE, in the proliferation, migration and invasion of cells, in the protein expression of N-cadherin, vimentin and Snail, and in the expression of proteins in the Wnt/β-catenin pathway. However, an increase was displayed in the apoptosis of cells and the expression of E-cadherin. Compared with the control group of tumor-bearing nude mice, the sh-CRNDE group demonstrated slowed tumor growth, reduced tumor weight and elevated E-cadherin, as well as reduced expression of N-cadherin, vimentin and Snail. In conclusion, silencing CRNDE may inhibit EMT, thus decreasing the migration and invasion of human OSCC cells by repressing the activation of the Wnt/β-catenin signaling pathway, thereby restricting cell growth and promoting cell apoptosis.

Clinical importance of FANCD2, BRIP1, BRCA1, BRCA2 and FANCF expression in ovarian carcinomas

OBJECTIVE

DNA repair pathways are potential targets of molecular therapy in cancer patients. The FANCD2, BRIP1, BRCA1/2, and FANCF genes are involved in homologous recombination DNA repair, which implicates their possible role in cell response to DNA-damaging agents. We evaluated a clinical significance of pre-treatment expression of these genes at mRNA level in 99 primary, advanced-stage ovarian carcinomas from patients, who later received taxane-platinum (TP) or platinum-cyclophosphamide (PC) treatment.

METHODS

Gene expression was determined with the use of Real-Time PCR. The BRCA2 and BRIP1 gene sequence was investigated with the use of SSCP, dHPLC, and PCR-sequencing.

RESULTS

Increased FANCD2 expression occurred to be a negative prognostic factor for all patients (PC+TP:HR 3.85, p = 0.0003 for the risk of recurrence; HR 1.96, p = 0.02 for the risk of death), and this association was even stronger in the TP-treated group (HR 6.7, p = 0.0002 and HR 2.33, p = 0.01, respectively). Elevated BRIP1 expression was the only unfavorable molecular factor in the PC-treated patients (HR 8.37, p = 0.02 for the risk of recurrence). Additionally, an increased FANCD2 and BRCA1/2 expression levels were associated with poor ovarian cancer outcome in either TP53-positive or -negative subgroups of the TP-treated patients, however these groups were small. Sequence analysis identified one protein truncating variant (1/99) in BRCA2 and no mutations (0/56) in BRIP1.

CONCLUSIONS

Our study shows for the first time that FANCD2 overexpression is a strong negative prognostic factor in ovarian cancer, particularly in patients treated with TP regimen. Moreover, increased mRNA level of the BRIP1 is a negative prognostic factor in the PC-treated patients. Next, changes in the BRCA2 and BRIP1 genes are rare and together with other analyzed FA genes considered as homologous recombination deficiency may not affect the expression level of analyzed genes.

MEG3: an Oncogenic Long Non-coding RNA in Different Cancers

Long noncoding RNAs (lncRNAs) have recently considered as central regulators in diverse biological processes and emerged as vital players controlling tumorigenesis. Several lncRNAs can be classified into oncogenes and tumor suppressor genes depending on their function in cancer. A maternally expressed gene 3 (MEG3) gene transcripts a 1.6 kb lncRNA whose act as an antitumor component in different cancer cells, such as breast, liver, glioma, colorectal, cervical, gastric, lung, ovarian and osteosarcoma cancer cells. The present review highlights biological function of MEG3 to repress tumor through regulating the major tumor suppressor genes p53 and Rb, inhibiting angiogenesis-related factor, or controlling miRNAs. On the other hand, previous studies have also suggested that MEG3 mediates epithelial-mesenchymal transition (EMT). However, deregulation of MEG3 is associated with the  development and progression of cancer, suggesting that MEG3 may function as a potential biomarker and therapeutic target for human cancers.

Long non-coding RNA CRNDE in cancer prognosis: Review and meta-analysis

BACKGROUND

Colorectal neoplasia differentially expressed (CRNDE), a 1910-nt lncRNA encoded on human chromosome 16, has been found to be involved in various cancers. Nevertheless, the clinical and diagnostic values of CRNDE in tumors still need to be explored. In this review, we aimed to elucidate the clinical role of CRNDE in cancer by searching all correlative literature, and we sequentially explored the association between CRNDE levels and overall survival (OS) or clinicopathological characteristics of cancer.

METHODS

We conducted a database search of PubMed, Wanfang Data, Ovid, SinoMed, China National Knowledge Infrastructure, Cochrane Library, and Web of Science (up to January 1, 2018). The pooled odds ratio (OR) and hazard ratio (HR) were used to assess extents of correlation between CRNDE and cancer prognosis. After identification of the inclusion and exclusion criteria, 12 articles including 1361 patients were selected for this review.

RESULTS

The results suggested that high levels of CRNDE were highly related to poor OS in tumor patients, with pooled HRs of 2.314 (1.894-2.826, P < .001, fixed-effects model). Likewise, we also found that high CRNDE expression was correlated with high tumor stage [OR: 3.340, 95% confidence interval (CI): 2.417-4.616, P < .001, random-effects model] and lymph node metastasis (OR: 3.027, 95% CI: 2.071-4.425, P = .004, random-effects model).

CONCLUSIONS

Our findings demonstrated that CRNDE may modify susceptibility for various cancers and may serve as a new predictive factor for prognosis and diagnosis in different types of cancers.

LncRNA CRNDE is a biomarker for clinical progression and poor prognosis in clear cell renal cell carcinoma

Colorectal neoplasia differentially expressed (CRNDE) served as an oncogenic long noncoding RNA (lncRNA) to be involved in the initialization and development of human cancers. However, the clinical significance and biological function of CRNDE in clear cell renal cell carcinoma (ccRCC) was not fully understood. In our study, we found CRNDE levels were increased in ccRCC tissue specimens and cell lines, and corrected with advanced clinical stage, large tumor size, lymph node metastasis, distant metastasis, and poor pathological grade in patients with ccRCC. Furthermore, levels of CRNDE were negatively correlated with overall survival of patients with ccRCC, and high-expression of CRNDE was an independent poor prognostic factor for patients with ccRCC. Moreover, loss-of-function and gain-of-function approaches showed CRNDE-enhanced ccRCC cell migration and invasion through modulating EMT-associated genes. In conclusion, CRNDE acts as an oncogenic lncRNA in ccRCC.

Altered long noncoding RNAs and survival outcomes in ovarian cancer: A systematic review and meta-analysis (PRISMA Compliant)

BACKGROUND

Previous studies investigating the association between altered long noncoding RNAs (lncRNAs) and survival outcomes in ovarian cancer have obtained controversial results. To comprehensively evaluate the association, we conducted a systematic review and meta-analysis of the studies published on the subject.

METHODS

We performed a systematic search using the databases of the Cochrane Central Register of Controlled Trials, PubMed, and Embase to find all relevant articles from inception to May 7, 2017. Studies that evaluated the association between 1 specific lncRNA and survival outcomes in ovarian cancer were included. Pooled hazard ratios (HRs) and 95% confidence intervals (95% CIs) for overall survival, progression-free survival, and disease-free survival were calculated with a fixed-effects or random-effects model.

RESULTS

A total of 15 studies involving 1333 patients with ovarian cancer were included in this meta-analysis. Altered lncRNAs were associated with decreased overall survival (HR: 2.29, 95% CI: 1.92-2.75) without heterogeneity (I = 0.0%) in ovarian cancer. Altered lncRNAs were also associated with decreased progression-free survival (HR: 2.77, 95% CI: 1.00-7.62, I = 76.6%) and disease-free survival (HR: 2.59, 95% CI: 0.89-7.57, I = 62.9%) in ovarian cancer.

CONCLUSION

Our results supported the strong prognostic value of altered lncRNAs in ovarian cancer. Further large-scale studies should be carried out to verify the clinical applications of altered lncRNAs in the prognosis assessment of ovarian cancer.

Colorectal neoplasia differentially expressed: a long noncoding RNA with an imperative role in cancer

Colorectal neoplasia differentially expressed (CRNDE), as a long noncoding RNA (lncRNA), has attracted increasing attention in recent years and has been documented to be at abnormally high expression in various types of cancer, such as colorectal cancer, glioma, hepatocellular carcinoma, lung cancer, and breast cancer. It could not only be used as a clinical biomarker for the early diagnosis and prognosis evaluation in a variety of cancers but also promote the development and progress of various tumor cells. Moreover, it is involved in the targeting regulation of multiple microRNAs and the activation/inhibition of multiple signaling pathways. In this review, we presented a systematic summary of the potential carcinogenicity and clinical value of CRNDE in the current evidence, so as to provide reference for early diagnosis, prognosis evaluation, and targeted therapy of various clinical cancers.

Aberrant lncRNA Expression in Multiple Myeloma

Multiple myeloma (MM), a type of malignant tumor, is characterized by dysplasia of clonal plasma cells in the bone marrow. People with MM will have damaged organs or tissues due to secretion of large amounts of monoclonal immunoglobulin or fragments (M protein). Despite improved survivability by novel treatment strategies over the last decade, MM is still incurable by current therapies. Long noncoding RNAs (lncRNAs), with length of more than 200 nucleotides, have been reported to act as important regulators in many diseases, including MM. Recent studies have reported aberrant lncRNA expression in MM; these dysregulated lncRNAs can play oncogenic and/or tumor-suppressive roles in the development and progression of MM. In this article, we present a general overview on the role of lncRNAs in MM pathogenesis and discuss their potential as prognostic biomarkers and targets for treatment.

Knockdown CRNDE alleviates LPS-induced inflammation injury via FOXM1 in WI-38 cells

OBJECTIVE

Pneumonia is the leading global cause of mortality and morbidity in children and elderly people worldwide. The lncRNA colorectal neoplasia differentially expressed (CRNDE) plays an important role in the human development and disease progression. The present study was aimed to investigate the effect of CRNDE on LPS-induced injuries in WI-38 cells and explore the potential mechanism.

METHODS

WI-38 cells were treated with LPS to induce injuries. The expression of CRNDE and FOXM1 in WI-38 cells were altered by transient transfection assay. Cell viability was measured by CCK-8 assay and cell apoptosis was detected by flow cytometry assay and western blot. The levels of inflammatory cytokines were assessed by ELISA and western blot. Furthermore, western blot analysis was performed to detect the expression levels of NF-κB and JAK/STAT pathway-related proteins.

RESULTS

LPS exposure induced cell injuries and increased CRNDE expression in WI-38 cells. CRNDE overexpression enhanced cell injuries in WI-38 cells with significantly reducing cell viability, increasing cell apoptosis and inflammatory cytokines levels. In addition, CRNDE overexpression further activated the NF-κB and JAK/STAT pathways in LPS-injured WI-38 cells. Inversely, opposite results were observed in CRNDE inhibition treatment group. Interestingly, FOXM1 was up-regulated by CRNDE and FOXM1 silence blocked the effect of CRNDE overexpression in cell apoptosis, inflammation and activation of NF-κB and JAK/STAT signaling pathways.

CONCLUSION

This study demonstrated that CRNDE overexpression accelerated LPS-induced apoptosis and inflammation via up-regulation of FOXM1 in WI-38 cells.

Role of lncRNAs in ovarian cancer: defining new biomarkers for therapeutic purposes

Long noncoding RNAs (lncRNAs) are a class of noncoding RNA, involved in regulation of diverse physiological and pathological processes. Ovarian cancer is the leading cause of death among all gynecological malignancies in the world and its underlying mechanism is still unclear. LncRNAs exhibit multiple biological functions in various stages of ovarian cancer development. We will discuss and summarize the new and important lncRNAs and their involvement in disease, which might represent promising therapeutic targets. Therapeutic intervention based on silencing or functional inhibition of target lncRNAs will be beneficial for ovarian cancer patients.

CRNDE Expression Positively Correlates with EGFR Activation and Modulates Glioma Cell Growth

BACKGROUND

The long non-coding RNA CRNDE has emerged as an important regulator in carcinogenesis and cancer progression. While CRNDE has previously been found to be the most highly upregulated lncRNA in glioma, detailed information on its roles in regulating cancer cell growth remains limited.

OBJECTIVE

In the present study, we aimed at exploring the functional roles and underlying mechanisms of CRNDE in glioma.

METHODS

We applied microarray data analysis to determine the prognostic significance of CRNDE in glioma patients and its correlation with epidermal growth factor receptor (EGFR) activation. EGFR inhibition was used to confirm the role of EGFR in regulating CRNDE expression. Functional studies were performed upon CRNDE silencing to explore its role in gliomagenesis.

RESULTS

We confirm that CRNDE acts as an oncogene that is highly up-regulated in glioma, and high CRNDE expression correlates with poor prognosis in glioma patients. We further demonstrate that the expression of CRNDE correlates with EGFR activation. EGF and EGFR tyrosine kinase inhibitor (TKI) enhance and block the up-regulation of CRNDE expression, respectively, suggesting that EGFR signaling may positively regulate CRNDE expression. Functional assays show that CRNDE depletion inhibits glioma cell growth both in vitro and in vivo, and is associated with induced cellular apoptosis with decreased Bcl2/Bax ratio.

CONCLUSIONS

Our findings suggest that the aberrant expression of CRNDE may be mediated by activated EGFR signaling and play significant roles in gliomagenesis.

Long non-coding RNA CRNDE as a potential prognostic biomarker in solid tumors: A meta-analysis

BACKGROUND AND AIM

Long non-coding RNA colorectal neoplasia differentially expressed (CRNDE) has been demonstrated to be highly expressed in many malignant tumors; however, the role of CRNDE in cancer remains undetermined because of limitations in sample size. We conducted a meta-analysis to assess the role of CRNDE in cancer.

METHODS

PubMed, Medline, Cochrane Library, Web of Science, EMBASE database, Ovid, Chinese CNKI, and Chinese WanFang database were systematically searched. The relation between CRNDE and the clinicopathological characteristics and prognosis of patients with cancer was determined using pooled odds ratios (ORs) and hazard ratios (HRs) with 95% confidence interval (CI).

RESULTS

Thirteen studies with 1570 patients were included. The pooled results indicated that high CRNDE expression was related to lymph node metastasis (YES vs. NO: OR = 3.50, 95% CI = [1.05, 8.09]) and TNM stage (I + II vs. III + IV: OR = 0.26, 95% CI = [0.18, 0.37]) but not to gender, tumor size, and differentiation. High CRNDE expression indicated poor overall survival (OS) (HR = 2.06, 95% CI = [1.66, 2.47]). CRNDE could be an independent predictive factor for OS (HR = 1.62, 95% CI = [1.15, 2.08]) in patients with cancer.

CONCLUSION

Therefore, high CRNDE expression was associated with advanced clinicopathological characteristics, and CRNDE could be used as a reliable prognostic biomarker in human cancer. However, more high-quality studies with a large sample size are needed to support this meta-analysis.

CRNDE: An important oncogenic long non-coding RNA in human cancers

Aberrant overexpression of long non-coding RNA CRNDE (Colorectal Neoplasia Differentially Expressed) is confirmed in various human cancers, which is correlated with advanced clinicopathological features and poor prognosis. CRNDE promotes cancer cell proliferation, migration and invasion, and suppresses apoptosis in complicated mechanisms, which result in the initialization and development of human cancers. In this review, we provide an overview of the oncogenic role and potential clinical applications of CRNDE.

LncRNA, CRNDE promotes osteosarcoma cell proliferation, invasion and migration by regulating Notch1 signaling and epithelial-mesenchymal transition

Osteosarcoma is the most common bone malignancy in adolescence. Recently, the long non-coding RNAs (lncRNAs) were reported to play important roles in osteosarcoma progression. The present study examined the potential role of the lncRNA, Colorectal Neoplasia Differentially Expressed (CRNDE) and molecular mechanisms underlying osteosarcoma progression. In the present study, we identified that CRNDE was up-regulated in osteosarcoma tissues and cell lines, and CRNDE expression level was significantly higher in osteosarcoma tissues from patients with advanced stage and metastasis. Overexpression of CRNDE promoted cell growth, cell proliferation, cell invasion and migration, and increased cell population at S phase with a decreased cell population at G₀/G₁ phase in MG-63 cells. Knock-down of CRNDE suppressed cell growth, cell proliferation, cell invasion and migration, and decreased cell population at S phase with an increased cell population at G₀/G₁ phase in U2OS cells. Overexpression of CRNDE was found to enhance the activity of Notch1 signaling and promote epithelial-mesenchymal transition (EMT) in MG-63 cells, while knock-down of CRNDE exerted the opposite effects in U2OS cells. The in vivo results showed that knock-down of CRNDE suppressed the tumor growth in the nude mice inoculated with osteosarcoma cells, and knock-down of CRNDE also suppressed the mRNA expression of Notch1, JAG1, N-cadherin, vimentin, and increased the mRNA expression of E-cadherin in the tumor tissues. Collectively, our results indicated that CRNDE functioned as an oncogene in osteosarcoma cell lines, and CRNDE may exert its oncogenic role via regulating Notch1 signaling and EMT in osteosarcoma.

A novel SNP in promoter region of RP11-3N2.1 is associated with reduced risk of colorectal cancer

Single-nucleotide polymorphisms (SNPs) in the promoter region of long intergenic non-coding RNAs (lincRNAs) could play a regulatory role in its expression level and then get involved in colorectal cancer (CRC). Thus, we conducted a two-stage case-control study to investigate the associations of Tag SNPs within the promoter region of selected lincRNAs from microarray data with risk of CRC. A total of 320 cases and 319 controls were recruited in the test set to explore the associations between 16 SNPs with no deviations from Hardy-Weinberg equilibrium (HWE) and risk of CRC. Furthermore, 501 cases and 538 controls were included as the validation set to confirm the significant associations. RP11-3N2.1 rs13230517 polymorphism was found to be negatively associated with CRC in both test set (AA vs. GG, OR = 0.68, 95% CI = 0.48-0.96) and validation set (AA vs. GG, OR = 0.76, 95% CI = 0.59-0.98). Pooled analysis showed that individuals with GA/AA genotypes had a significantly decreased risk of CRC when compared with those carrying GG genotype (OR = 0.74, 95% CI = 0.60-0.90) in the combined set. The crossover analysis revealed that rs13230517 GA/AA carriers had a decreased risk of CRC than GG carriers among non-drinkers in both test and combined set. However, no gene-environment multiplicative interactions were found on risk of CRC. Our findings suggest that rs13230517 polymorphism might participate in the pathogenesis of CRC and have the potential to be a biomarker for predicting the risk of CRC.

The long non-coding RNA CRNDE acts as a ceRNA and promotes glioma malignancy by preventing miR-136-5p-mediated downregulation of Bcl-2 and Wnt2

The colorectal neoplasia differentially expressed (CRNDE) gene encodes a long non-coding RNA (lncRNA) that is the most unregulated among 129 lncRNAs differentially expressed in gliomas. In this study, we confirmed high CRNDE expression in clinical glioma specimens and observed through experiments in human glioma cell lines a novel molecular mechanism by which CRNDE may contribute to glioma pathogenesis. By inducing or silencing CRNDE expression, we detected a positive correlation between CRNDE levels and the proliferative, migratory, and invasive capacities of glioma cells, which were concomitant with a decreased apoptosis rate. Our experiments also suggest that these effects are mediated by downregulation of miR-136-5p, which correlated with the glioma WHO grade. Based on predicted CRNDE/miR-136-5p/mRNA interactions, both the mRNA and protein expression analyses suggested that miR-136-5p-mediated repression of Bcl-2 and Wnt2 underlies the pro-tumoral actions of CRNDE. We therefore propose that CRNDE functions as a competing endogenous RNA (ceRNA) that binds to and negatively regulates miR-136-5p, thereby protecting Bcl-2 and Wnt2 from miR-136-5p-mediated inhibition in glioma.

RNA-sequencing investigation identifies an effective risk score generated by three novel lncRNAs for the survival of papillary thyroid cancer patients

Scholars are striving to apply molecular biology involving long non-coding RNA (lncRNA) in the prognostication of papillary thyroid cancer (PTC). However, the clinical role of lncRNAs in the prognostic setting of PTC is still unclear. Herein, a comprehensive inquiry was performed to screen lncRNA expression profiling with 507 PTC patients from The Cancer Genome Atlas RNA-sequencing datasets. A total of 734 lncRNAs were detected to be aberrantly expressed, among which three novel lncRNAs including AC079630.2, CRNDE and CTD-2171N6.1 were markedly related to the progression and survival of PTC. Furthermore, the aberrant expression of these lncRNAs could be verified by other cohorts from gene expression omnibus (GEO) as detected by microarrays. Next, we established a three-lncRNA signature and divided the PTC patients into two subgroups of high- and low-risk. Interestingly, patients with high-risk tended to gain obviously poorer outcome. Most importantly, this three-lncRNA signature was an independent biomarker to predict the patient survival of PTC. The accurate molecular roles of these three lncRNAs remains unclarified and warrants further characterization, but our current data propose that they might play pivotal roles in PTC tumorigenesis and more importantly, these novel lncRNAs are closely related to patients' survival. These discoveries will have far-reaching consequences with respect to molecular prediction of PTC.

Diagnostic potential of serum exosomal colorectal neoplasia differentially expressed long non-coding RNA (CRNDE-p) and microRNA-217 expression in colorectal carcinoma

In this study, we investigated the diagnostic potential of serum exosomal colorectal neoplasia differentially expressed (CRNDE-p) long coding RNA and microRNA-217 in colorectal carcinoma (CRC). We detected high CRNDE-p and low miR-217 levels in exosomes released by multiple CRC cell lines into culture media as well as in sera from CRC xenograft mice and CRC patients. Conversely, we observed lower CRNDE-p and higher miR-217 levels in serum exosomes from post-chemotherapy than from pre-chemotherapy patient samples. The area under curve (AUC) value for the serum exosomal CRNDE-p and miR-217 combination was higher than CRNDE-p or miR-217 alone. Moreover, high CRNDE-p and low miR-217 serum exosomal levels correlated with advanced clinical stages (III/IV), tumor classification (T3/T4), and lymph node or distant metastasis. Thus combined evaluation of serum exosomal CRNDE-p and miR-217 levels show diagnostic and prognostic potential for CRC patients.

Long noncoding RNA CRNDE stabilized by hnRNPUL2 accelerates cell proliferation and migration in colorectal carcinoma via activating Ras/MAPK signaling pathways

Recent studies have furthered our understanding of the function of long noncoding RNAs (lncRNAs) in numerous biological processes, including cancer. This study investigated the expression of a novel lncRNA, colorectal neoplasia differentially expressed (CRNDE), in colorectal carcinoma (CRC) tissues and cells by real-time RT-PCR and in situ hybridization, and its biological function using a series of in vitro and in vivo experiments to determine its potential as a prognostic marker and therapeutic target. CRNDE was found to be upregulated in primary CRC tissues and cells (P<0.05), and the upregulation of CRNDE expression is a powerful predictor of advanced TNM stage (P<0.05) and poor prognosis for CRC patients (P=0.002). The promoting effects of CRNDE on the cell proliferation, cell cycling and metastasis of CRC cells were confirmed both in vitro and in vivo by gain-of-function and loss-of-function experiments. Mechanistically, it was demonstrated that CRNDE could form a functional complex with heterogeneous nuclear ribonucleoprotein U-like 2 protein (hnRNPUL2) and direct the transport of hnRNPUL2 between the nucleus and cytoplasm. hnRNPUL2 that was accumulated in the cytoplasm could interact with CRNDE both physically and functionally, increasing the stability of CRNDE RNA. Moreover, gene expression profile data showed that CRNDE depletion in cells downregulated a series of genes involved in the Ras/mitogen-activated protein kinase signaling pathways. Collectively, these findings provide novel insights into the function and mechanism of lncRNA CRNDE in the pathogenesis of CRC and highlight its potential as a therapeutic target for CRC intervention.

Long Noncoding RNA CRNDE/PRC2 Participated in the Radiotherapy Resistance of Human Lung Adenocarcinoma Through Targeting p21 Expression

Long noncoding RNAs (lncRNAs), a new class of functional regulators involved in human tumorigenesis, have been attracting the increasing attention of researchers. The lncRNA colorectal neoplasia differentially expressed (CRNDE) gene, transcribed from chromosome 16 on the strand opposite the adjacent IRX5 gene, was originally found to be increased in CRC and was reported to be abnormally expressed in many cancers. However, its potential role and the molecular mechanism underlying the radioresistant phenotype formation of lung adenocarcinoma (LAD) remain unclear. In our present study, we identified that CRNDE was significantly upregulated in LAD tissue and radioresistant LAD cell lines. A high level of CRNDE expression was significantly correlated with poor differentiation, TNM stage, lymph node metastasis, radiotherapy response, and a significantly shorter overall survival. Gain- and loss-of-function tests revealed that CRNDE could influence the radiosensitivity of LAD cells by affecting the G₁/S transition and causing apoptosis of LAD cells in vitro. Additionally, the mechanistic investigations showed that CRNDE could interact with PRC2 and recruit its core component EZH2 to p21 (CDKN1A) promoter regions and repress its transcription. Furthermore, rescue experiments were performed to confirm that CRNDE oncogenic function was partly through regulating p21. In conclusion, our data suggest that CRNDE may function as an oncogene by modulating p21, finally contributing to the radioresistant phenotype formation of LAD cells.

Association of a novel genetic variant in RP11-650L12.2 with risk of colorectal cancer in Han Chinese population

BACKGROUND

This study aimed to investigate the associations of selected polymorphisms in RP11-650L12.2 with the risk of colorectal cancer (CRC) in a Chinese population.

METHODS

A total of 821 CRC cases (test set: 320, validation set: 501) and 857 healthy controls (test set: 319, validation set: 538) were enrolled in this study. Demographic characteristics and lifestyle information were collected by a validated questionnaire. A sample of 5ml venous blood was collected from each subject for DNA isolation, and the selected polymorphisms (rs144182521, rs514743, rs76071148, rs149941240) were genotyped by MassArray technique.

RESULTS

The rs149941240 polymorphism was significantly associated with the risk of CRC, with ORs of 1.50 (95% CI: 1.15-1.96) by co-dominant model and 1.45 (95% CI: 1.21-1.87) by dominant model in the test set, respectively. Correspondingly, the ORs were 1.48 (95% CI: 1.19-1.82) and 1.41 (95% CI: 1.15-1.73) in the validation set, respectively. The crossover analysis showed that non-smokers with the variant genotypes in rs149941240 had a significantly increased risk of CRC than those with wild genotype by dominant model in the validation set (OR 1.42, 95% CI 1.04-1.96). However, no gene-environment multiplicative interactions of rs149941240 with tobacco smoking were found on risk of CRC.

CONCLUSIONS

Our findings suggest that rs149941240 polymorphism was associated with the risk of CRC, and might contribute to the susceptibility to CRC. The effects of this polymorphism should be validated in a larger sample and require further mechanistic investigations to determine the nature of its influence on CRC.

Long noncoding RNA CRNDE activates Wnt/β-catenin signaling pathway through acting as a molecular sponge of microRNA-136 in human breast cancer

Long non-coding RNAs (lncRNAs) serve critical roles in the tumorigenesis and development of multiple human malignancies. Herein, we aimed to explore the biological and clinical significance of lncRNA CRNDE in human breast cancer (BC). The expression of CRNDE in BC tissues and cell lines was detected, and the association between CRNDE expression and clinicopathologic features of BC patients was also analyzed. Novel targets of CRNDE were identified through a bioinformatics search and confirmed using a dual-luciferase reporter system. Gain and loss-of-function studies were carried out to verify whether CRNDE exerts its biological functions through its downstream target. CCK-8, colony formation, wound-healing, and transwell assays were applied to detect the altered phenotypes of BC cell lines in vitro after transfection. Tumor xenografts were created to detect the function of CRNDE in vivo tumorigenesis. CRNDE expression is remarkably up-regulated in BC tissue specimens and cell lines in comparison to corresponding normal tissues and normal human breast epithelial cells. Up-regulated CRNDE expression was greatly associated with larger tumor size, advanced TNM stage and unfavorable prognosis of BC patients. We uncovered that miR-136 is a bona fide binding target of CRNDE, and that up-regulation of CRNDE promoted the mRNA and protein expressions of β-catenin, c-myc and cyclinD1. Overexpressed CRNDE facilitated in vitro cell proliferation, migration and invasion of BC cells. In vivo assay showed that the average tumor volume and weight were largest in the group of CRNDE overexpression. CRNDE might hyperactivate the Wnt/β-catenin signaling pathway through directly repressing miR-136 expression in BC; CRNDE could be considered as a prognostic biomarker and therapeutic target in BC diagnosis and treatment.

Meta-signature LncRNAs serve as novel biomarkers for colorectal cancer: integrated bioinformatics analysis, experimental validation and diagnostic evaluation

The aim of this study is to explore the differentially expressed lncRNAs, which may have potential biological function and diagnostic value in colorectal cancer (CRC). Through integrated data mining, we finally identified nine differentially expressed lncRNAs and their potential mRNA targets. After a series of bioinformatics analyses, we screened significant pathways and GO terms that are related to the up-regulated and down-regulated transcripts respectively. Meanwhile, the nine lncRNAs were validated in 30 paired tissues and cell lines by qRT-PCR and the results were basically consistent with the microarray data. We also tested the nine lncRNAs in the serum of 30 CRC patients matched with the CRC tissue, 30 non-cancer patients and 30 health controls. Finally, we found that BLACAT1 was significant for the diagnosis of CRC. The area under the curve (AUC), sensitivity and specificity were 0.858 (95% CI: 0.765-0.951), 83.3% and 76.7% respectively between CRC patients and health controls. Moreover, BLACAT1 also had distinct value to discriminate CRC from other non-cancer diseases. The results indicated that the differentially expressed lncRNAs and their potential target transcripts could be considered as potential therapeutic targets for CRC patients. Meanwhile, lncRNA BLACAT1 might represent a new supplementary biomarker for the diagnosis of CRC.

Prognosis of patients with BRCA1-associated ovarian carcinomas depends on TP53 accumulation status in tumor cells

OBJECTIVE

TP53 mutation is the most frequent molecular event in BRCA1-associated ovarian carcinomas. TP53 status may be a confounding factor in the evaluation of clinical importance of other proteins. We aimed to evaluate the clinical significance of BRCA1 mutations with respect to the TP53 accumulation status in 159 high-grade ovarian carcinomas.

METHODS

Statistical analyses were done with the Kaplan-Meier method, log-rank test, the Cox's and logistic regression models for all patients, and in subgroups with and without TP53 accumulation (TP53+ and TP53-, respectively).

RESULTS

Forty of 159 ovarian carcinomas (25.2%) were diagnosed in patients with BRCA1 germline mutations; 102 tumors (64.2%) were TP53+ and 57 (37.8%) were TP53-. Among patients with TP53+ carcinomas, BRCA1 carriers had increased odds of recurrence compared with sporadic cases (HR 2.25, P=0.003; median disease-free survival time 7.7 vs. 18.4months, respectively). In the smaller TP53- subgroup, BRCA1 mutation reduced the risk of death by 46% (HR 0.54, P=0.099, median overall survival time 42.7 vs. 28.1months), but beyond the border of significance. When the TP53 status was not taken into account, BRCA1 mutations did not show any significance, however, there was a trend toward increased odds of complete remission for women with BRCA1 mutations compared to non-carriers (OR 2.47, P=0.064). Taxane-platinum therapy showed advantage over the platinum-cyclophosphamide one in the entire group of patients and in the TP53+ subgroup.

CONCLUSIONS

Our results suggest that the TP53 accumulation status determines the prognosis of BRCA1 mutation carriers with high-grade ovarian carcinomas.

Long Non-Coding RNAs As Potential Novel Prognostic Biomarkers in Colorectal Cancer

Colorectal cancer (CRC) is the fourth most common cause of death worldwide. Surgery is usually the first line of treatment for patients with CRC but many tumors with similar histopathological features show significantly different clinical outcomes. The discovery of robust prognostic biomarkers in patients with CRC is imperative to achieve more effective treatment strategies and improve patient's care. Recent progress in next generation sequencing methods and transcriptome analysis has revealed that a much larger part of the genome is transcribed into RNA than previously assumed. Collectively referred to as non-coding RNAs (ncRNAs), some of these RNA molecules such as microRNAs (miRNAs) and long non-coding RNAs (lncRNAs) have been shown to be altered and to play critical roles in tumor biology. This discovery leads to exciting possibilities for personalized cancer diagnosis, and therapy. Many lncRNAs are tissue and cancer-type specific and have already revealed to be useful as prognostic markers. In this review, we focus on recent findings concerning aberrant expression of lncRNAs in CRC tumors and emphasize their prognostic potential in CRC. Further studies focused on the mechanisms of action of lncRNAs will contribute to the development of novel biomarkers for diagnosis and disease progression.