LncRNA KCNQ1OT1 acts as miR-216b-5p sponge to promote colorectal cancer progression via up-regulating ZNF146

A Regulatory Circuits Analysis Tool, "miRCuit," Helps Reveal Breast Cancer Pathways: Toward Systems Medicine in Oncology

A systems medicine understanding of the regulatory molecular circuits that underpin breast cancer is essential for early cancer detection and precision/personalized medicine in clinical oncology. Transcription factors (TFs), microRNAs (miRNAs), and long non-coding RNAs (lncRNAs) control gene expression and cell biology, and by extension, serve as pillars of the regulatory circuits that determine human health and disease. We report here the development of a regulatory circuit analysis program, miRCuit, constructing 10 different types of regulatory elements involving messenger RNA, miRNA, lncRNA, and TFs. Using the miRCuit, we analyzed expression profiling data from 179 invasive ductal breast carcinoma and 51 normal tissue samples from the Gene Expression Omnibus database. We identified eight circuit types along with two special types of circuits, one of which highlighted the significant roles of lncRNA CASC15, miR-130b-3p, and TF KLF5 in breast cancer development and progression. These findings advance our understanding of the regulatory molecules associated with breast cancer. Moreover, miRCuit offers a new avenue for users to construct circuits from regulatory molecules for potential applications to decipher disease pathogenesis.

Rs1347093 regulates microRNA-216/-217 expression and is associated with pancreatic cancer risk

BACKGROUND

Single nucleotide polymorphism (SNP) rs1347093 shows statistically significant association with lung cancer risk, but there is no further rs1347093 expression quantitative trait loci (eQTL) effect information. SNP rs1347093 is located in microRNA-216/-217 (miR-216/-217) locus. In addition, miR-216/-217 have pancreas-enriched expressions. In this study, we examined a potential miR-216/-217 promoter region, and investigated the effect of rs1347093-A allele on the miR-216/-217 promoter activity.

METHODS

Bioinformatics analysis, quantitative real-time PCR, luciferase reporter assay, Western blotting, and cell counting kit-8 (CCK-8) assay were performed.

RESULTS

The miR-216/-217 expressions are down-regulated in pancreatic cancer. In pancreatic cancer patients carrying the rs1347093-A allele, miR-216/-217 expressions were more largely suppressed. We identified a potential promoter region in miR-216/-217 locus and further showed that rs1347093-A allele resulted in significantly reduced promoter activity in pancreatic cancer cells, which could be mediated by MEF2C activities. In terms of mechanism in the pathogenesis of pancreatic cancer, miR-216b-5p expression was down-regulated, thereby preventing it from interacting with beclin-1 mRNA while promoting the survival of pancreatic cancer cells.

CONCLUSIONS

This study may reveal the biological relevance underlying rs1347093-A allele with an increase in pancreatic cancer risk. SNP rs1347093 could be meaningful as a novel biomarker for pancreatic cancer risk.

Epigenetic regulation of autophagy by non-coding RNAs and exosomal non-coding RNAs in colorectal cancer: A narrative review

One of the major diseases affecting people globally is colorectal cancer (CRC), which is primarily caused by a lack of effective medical treatment and a limited understanding of its underlying mechanisms. Cellular autophagy functions to break down and eliminate superfluous proteins and substances, thereby facilitating the continual replacement of cellular elements and generating vital energy for cell processes. Non-coding RNAs and exosomal ncRNAs have a crucial impact on regulating gene expression and essential cellular functions such as autophagy, metastasis, and treatment resistance. The latest research has indicated that specific ncRNAs and exosomal ncRNA to influence the process of autophagy in CRC cells, which could have significant consequences for the advancement and treatment of this disease. It has been determined that a variety of ncRNAs have a vital function in regulating the genes essential for the formation and maturation of autophagosomes. Furthermore, it has been confirmed that ncRNAs have a considerable influence on the signaling pathways associated with autophagy, such as those involving AMPK, AKT, and mTOR. Additionally, numerous ncRNAs have the potential to affect specific genes involved in autophagy. This study delves into the control mechanisms of ncRNAs and exosomal ncRNAs and examines how they simultaneously influence autophagy in CRC.

A review on the role of KCNQ1OT1 lncRNA in human disorders

KCNQ1OT1 is an lncRNA located within KCNQ1 gene on chromosome 11p15.5. This lncRNAs participates in the pathogenesis of a diversity of cancers as well as non-cancerous conditions. In most types of cancers, KCNQ1OT1 is regarded as an oncogene. In a wide array of cancers, high level of KCNQ1OT1 is associated with lower overall survival time. This lncRNA has been found to adsorb a variety of miRNAs, namely miR-15a, miR-211-5p, hsa-miR-107, miR-145, miR-34a, miR-204-5p, miR-129-5p, miR-372-3p, miR-491-5p, miR-153, miR-185-5p, miR-124-3p, miR-211-5p, miR-149, miR-148a-3p, miR-140-5p, miR-125b-5p, miR-9, miR-329-3p, miR-760, miR-296-5p, miR-3666 and miR-129-5p, thus regulating the downstream targets of these miRNAs. In this manuscript, our attention is on this lncRNA and its biomolecular roles in human cancers and other disorders. KCNQ1OT1 plays significant roles in the tumorigenesis and may function as a prospective target for cancer therapy.

Biological role of long non-coding RNA KCNQ1OT1 in cancer progression

Long non-coding RNAs (lncRNAs) are a type of RNAs that are more than 200 nucleotides without protein-coding potential. In recent years, more and more attention has been paid to the role of lncRNAs in cancer pathogenesis. LncRNA KCNQ1 overlapping transcript 1 (KCNQ1OT1) is located on chromosome 11p15.5 with a total length of 91 kb and is highly expressed in various malignancies, which is closely related to tumor growth, lymph node metastasis, survival cycle and recurrence rate. In addition, KCNQ1OT1 is involved in the regulation of PI3K/AKT and Wnt/β-catenin signaling pathways. In this review, the mechanism and related progress of KCNQ1OT1 in different cancers were reviewed. It was found that KCNQ1OT1 can stabilize mRNA expression through sponging miRNA, which not only induced tumor cell proliferation, migration, invasion, drug resistance, epithelial-mesenchymal transition (EMT) and inhibited cell apoptosis in vitro, but also promoted tumor growth and metastasis in vivo. Therefore, as a new biomarker and therapeutic target, KCNQ1OT1 has broad prospects for the diagnosis and treatment of different cancers.

LncRNA-SNHG1 promotes paclitaxel resistance of gastric cancer cells through modulating the miR-216b-5p-hexokianse 2 axis

Gastric cancer (GC) is one of the most malignant tumors with high incidence and poor prognosis. Currently, the combination of surgery with chemo- or radiotherapy is widely applied therapeutic strategy against GC. However, development of drug resistance severely limited the clinical application of chemotherapy. Small nucleolar RNA host gene 1 (SNHG1) has been reported to be frequently overexpressed in diverse human tumors. Yet, the biological roles and mechanisms of SNHG1 in chemoresistant GC remain unclear. Expressions of lncRNA and miRNA were detected by qRT-PCR. Responses of GC cells to Taxol treatments were evaluated by cell viability assay and apoptosis assay. Glucose metabolism rate was examined by glucose uptake and extracellular acidification rate (ECAR). The lncRNA-miRNA interaction was validated by RNA pull-down assay and luciferase assays. This study reports that expressions of SNHG1 were significantly elevated in patients with GC and gastric cancer cell lines. Silencing SNHG1 effectively suppressed GC cells migration and increased the Taxol sensitivity of GC cells. Moreover, we detected remarkedly upregulated SNHG1 expression and increased glucose metabolism in Taxol resistant cell line, MKN-45 TXR. Low glucose supply rendered Taxol resistant cells more susceptible to Taxol treatment compared with that from MKN-45 parental cells. Bioinformatical analysis, RNA pull-down and luciferase assays verified that SNHG1 functioned as a ceRNA of miR-216b-5p in GC cells. Consistently, we detected miR-216b-5p was significantly downregulated in GC tumor specimens and Taxol resistant GC cells. The hexokinase 2 (HK2), a glucose metabolism key enzyme, was predicted and validated as a direct target of miR-216b-5p in GC cells. Finally, restoration of miR-216b-5p in SNHG1-overexpressing MKN-45 TXR cells successfully overrode the SNHG1-promoted Taxol resistance through targeting the HK2-glycolysis axis. This study uncovered new biological roles and molecular mechanisms of the lncRNA-SNHG1-mediated Taxol resistance of gastric cancer, suggesting targeting the SNHG1-miR-216b-5p-HK2 axis could be a potentially therapeutic approach against chemoresistant gastric cancer.

Long Noncoding RNA ZBED5-AS1 Facilitates Tumor Progression and Metastasis in Lung Adenocarcinoma via ZNF146/ATR/Chk1 Axis

Long noncoding RNAs (lncRNAs) have been implicated in tumorigenesis, including lung adenocarcinoma (LUAD). However, the functional and regulatory mechanisms of lncRNAs in LUAD remain poorly understood. In this study, we investigated the role of lncRNA ZBED5-AS1 in LUAD. We found that ZBED5-AS1 was upregulated in LUAD specimens and overexpressed in LUAD cell lines. ZBED5-AS1 promoted LUAD cell proliferation, migration, and invasion in vitro and promoted LUAD cell growth in vivo. ZBED5-AS1 promoted ZNF146 expression, activating the ATR/Chk1 pathway and leading to LUAD progression. We observed that exosomes from LUAD cells have a higher expression of ZBED5-AS1 compared with exosomes from the normal cell line BEAS-2B. Coculture experiments with exosomes showed that ZBED5-AS1 expression was downregulated after coculture with Si-ZBED5-AS1 exosomes, and coculture with exosomes with low ZBED5-AS1 expression inhibited proliferation and invasion of LUAD cells. Our results indicate that ZBED5-AS1 functions as an oncogenic factor in LUAD cells by targeting the ZNF146/ATR/Chk1 axis.

Associations between KCNQ1OT1 genetic variation rs10766212 and susceptibility to colorectal cancer and clinical stage in a Chinese Han population

KCNQ1OT1 has been linked to the development and progression of colorectal cancer (CRC). As a result, functional polymorphisms in the KCNQ1OT1 gene may have a role in CRC formation and progression. The goal of this study was to see if the rs10766212 polymorphism on the KCNQ1OT1 gene was linked to CRC susceptibility and clinical stage in a Chinese Han population. The case-control research comprised a total of 576 CRC patients and 606 healthy controls. The genotype of the rs10766212 polymorphic locus was determined using the Sanger sequencing technique. We found that the KCNQ1OT1 rs10766212 polymorphism was not related to CRC susceptibility; however, it was connected with the clinical stage of CRC. Patients with CRC who had the rs10766212 T allele had a lower risk of stage III/IV tumors than those who had the rs10766212 C allele. Furthermore, CRC tissues with the rs10766212 CC genotype showed a significant negative connection between KCNQ1OT1 and hsa-miR-622 expression. The luciferase assay showed that the rs10766212 C allele might contribute to the adsorption of KCNQ1OT1 on hsa-miR-622. In conclusion, the rs10766212 polymorphism altering hsa-miR-622 binding is linked to the clinical stage of CRC and may serve as a biomarker for predicting CRC progression in the Chinese Han population. However, better-designed studies are still needed to confirm the current findings.

The Roles of Zinc Finger Proteins in Colorectal Cancer

Despite colorectal cancer remaining a leading worldwide cause of cancer-related death, there remains a paucity of effective treatments for advanced disease. The molecular mechanisms underlying the development of colorectal cancer include altered cell signaling and cell cycle regulation that may result from epigenetic modifications of gene expression and function. Acting as important transcriptional regulators of normal biological processes, zinc finger proteins also play key roles in regulating the cellular mechanisms underlying colorectal neoplasia. These actions impact cell differentiation and proliferation, epithelial-mesenchymal transition, apoptosis, homeostasis, senescence, and maintenance of stemness. With the goal of highlighting promising points of therapeutic intervention, we review the oncogenic and tumor suppressor roles of zinc finger proteins with respect to colorectal cancer tumorigenesis and progression.

TMEM147 is a novel biomarker for diagnosis and prognosis of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the most common type of liver malignancy with high incidence and poor prognosis. Transmembrane protein 147 (TMEM147) has been implicated in the development of colon cancer. However, the role of TMEM147 in HCC remains unclear. In this study, data of 371 HCC tissues, 50 adjacent nontumor tissues, and 110 normal liver tissues were retrieved from the TCGA and GTEx databases. TMEM147 expression was found to be increased in HCC tissues. High expression of TMEM147 was related to poor prognosis, and TMEM147 was confirmed to be an independent prognostic factor for HCC patients. A receiver operating characteristics (ROC) analysis was performed and showed that the diagnostic efficacy of TMEM147 was significantly higher than that of AFP (0.908 versus 0.746, p < 0.001). Furthermore, TMEM147 promoted tumor immune infiltration, and macrophages were the immune cells that predominantly expressed TMEM147 in HCC. Further analysis revealed that TMEM147 mainly impacted the ribosome pathway, and CTCF, MLLT1, TGIF2, ZNF146, and ZNF580 were predicted to be the upstream transcription factors for TMEM147 in HCC. These results suggest that TMEM147 serves as a promising biomarker for diagnosis and prognosis and may potentially become a therapeutic target for HCC.

Co-Occurrence of Beckwith-Wiedemann Syndrome and Early-Onset Colorectal Cancer

CRC is an adult-onset carcinoma representing the third most common cancer and the second leading cause of cancer-related deaths in the world. EO-CRC (<45 years of age) accounts for 5% of the CRC cases and is associated with cancer-predisposing genetic factors in half of them. Here, we describe the case of a woman affected by BWSp who developed EO-CRC at age 27. To look for a possible molecular link between BWSp and EO-CRC, we analysed her whole-genome genetic and epigenetic profiles in blood, and peri-neoplastic and neoplastic colon tissues. The results revealed a general instability of the tumor genome, including copy number and methylation changes affecting genes of the WNT signaling pathway, CRC biomarkers and imprinted loci. At the germline level, two missense mutations predicted to be likely pathogenic were found in compound heterozygosity affecting the Cystic Fibrosis (CF) gene CFTR that has been recently classified as a tumor suppressor gene, whose dysregulation represents a severe risk factor for developing CRC. We also detected constitutional loss of methylation of the KCNQ1OT1:TSS-DMR that leads to bi-allelic expression of the lncRNA KCNQ1OT1 and BWSp. Our results support the hypothesis that the inherited CFTR mutations, together with constitutional loss of methylation of the KCNQ1OT1:TSS-DMR, initiate the tumorigenesis process. Further somatic genetic and epigenetic changes enhancing the activation of the WNT/beta-catenin pathway likely contributed to increase the growth advantage of cancer cells. Although this study does not provide any conclusive cause-effect relationship between BWSp and CRC, it is tempting to speculate that the imprinting defect of BWSp might accelerate tumorigenesis in adult cancer in the presence of predisposing genetic variants.

Integrated transcriptome analysis reveals roles of long non-coding RNAs (lncRNAs) in caprine skeletal muscle mass and meat quality

Long non-coding RNAs (lncRNAs) play important roles in the growth and development of skeletal muscle. However, there is limited information on goats. In this study, expression profiles of lncRNAs in Longissimus dorsi muscle from Liaoning cashmere (LC) goats and Ziwuling black (ZB) goats with divergent meat yield and meat quality were compared using RNA-sequencing. Based on our previous microRNA (miRNA) and mRNA profiles obtained from the same tissues, the target genes and binding miRNAs of differentially expressed lncRNAs were obtained. Subsequently, lncRNA-mRNA interaction networks and a ceRNA network of lncRNA-miRNA-mRNA were constructed. A total of 136 differentially expressed lncRNAs were identified between the two breeds. Fifteen cis target genes and 143 trans target genes were found for differentially expressed lncRNAs, and they were enriched in muscle contraction, muscle system process, muscle cell differentiation, and p53 signaling pathway. A total of 69 lncRNA-trans target gene pairs were constructed, with close relationship with muscle development, intramuscular fat deposition, and meat tenderness. A total of 16 lncRNA-miRNA-mRNA ceRNA pairs were identified, of which some reportedly associated with skeletal muscle development and fat deposition were found. The study will provide an improved understanding of the roles of lncRNAs in caprine meat yield and meat quality.

miR-216b-5p Inhibited the Progression of Experimental Optic Neuritis via Downregulating FAS

Objective

Present study mainly explored the effect of miR-216b-5p on experimental optic neuritis and mechanism.

Methods

Female C57BL/6 mice were utilized to establish the EAE model. miR-216b-5p expression was measured by RT-qPCR. Protein expression was evaluated via western blot. Inflammatory infiltration score was analyzed by HE staining. Visual function was assessed by measuring the OKR. Flow cytometry assay was conducted to measure the percentage of IL-17 cells. ELISA was utilized to evaluate the immune factor.

Results

The EAE mouse model was successfully established. The EAE score of mice began to increase in EAE group after 11 days of MOG35-55 and CFA immunization. The degree of inflammatory cell infiltration in EAE mice was higher than that in normal mice. Compared with normal mice, the number of microglia and astrocytes was raised in EAE mice. miR-216b-5p expression was obviously declined and FAS expression was obviously raised in EAE. Compared with NC group, demyelination scores and axonal loss were markedly declined in miR-216b-5p mimic group. IL-17A concentration and the percentage of IL-17 cells were obviously declined in miR-216b-5p mimic group. FAS was predicted to be regulated by miR-216b-5p by TargetScan, and luciferase reporter assay confirmed this prediction. In addition, overexpression of FAS exacerbated experimental optic neuritis by promoting the inflammatory response and Th17 cell differentiation, and miR-216b-5p reversed this effect.

Conclusions

miR-216b-5p downregulated FAS and inhibited the progression of experimental optic neuritis via promoting the inflammatory response and Th17 cell differentiation.

Screening of lncRNA-miRNA-mRNA Coexpression Regulatory Networks Involved in Acute Traumatic Coagulation Dysfunction Based on CTD, GeneCards, and PharmGKB Databases

Competitive endogenous RNA (ceRNA) networks play crucial roles in multiple biological processes and development of diseases. They might serve as diagnostic and prognosis markers as well as therapeutic targets. The purpose of this study was to identify a novel ceRNA network involving KCNQ1OT1, hsa-miR-24-3p, and VWF in acute traumatic coagulopathy (ATC) based on databases search. We searched the CTD, GeneCards, and PharmGKB databases for ATC-related target genes using Coagulopathy as a keyword. Upstream miRNAs and lncRNAs of the candidate target VWF were then explored using the miRWalk, microT, TargetScan, RNA22 and Tarbase, and DIANA-LncBase and Starbase databases, respectively. A KCNQ1OT1-hsa-miR-24-3p-VWF ceRNA network was constructed by R “ggalluvial” package. Interaction between KCNQ1OT1, hsa-miR-24-3p, and VWF was examined, and their expression was quantified in the peripheral blood samples from 30 ATC patients and liver tissues of ATC rat models. Forty-one ATC-related target genes were identified following data retrieval from publicly available databases, of which VWF was selected as the target and used for the subsequent analysis. KCNQ1OT1 and hsa-miR-24-3p were confirmed to be the key upstream regulatory factors of VWF. KCNQ1OT1-hsa-miR-24-3p-VWF coexpression regulatory network was constructed where KCNQ1OT1 competitively bound to hsa-miR-24-3p and attenuated its binding to VWF. Both the liver tissues of ATC rats and peripheral blood samples from ATC patients showed increased hsa-miR-24-3p expression and decreased VWF and KCNQ1OT1 expression. Collectively, we described the KCNQ1OT1-hsa-miR-24-3p-VWF ceRNA network in the development of ATC. We propose a new ceRNA that could help in the diagnosis and treatment of ATC.

ZNF146/OZF and ZNF507 target LINE-1 sequences

Repetitive sequences including transposable elements and transposon-derived fragments account for nearly half of the human genome. While transposition-competent transposable elements must be repressed to maintain genomic stability, mutated and fragmented transposable elements comprising the bulk of repetitive sequences can also contribute to regulation of host gene expression and broader genome organization. Here, we analyzed published ChIP-seq data sets to identify proteins broadly enriched on transposable elements in the human genome. We show 2 of the proteins identified, C2H2 zinc finger-containing proteins ZNF146 (also known as OZF) and ZNF507, are targeted to distinct sites within LINE-1 ORF2 at thousands of locations in the genome. ZNF146 binding sites are found at old and young LINE-1 elements. In contrast, ZNF507 preferentially binds at young LINE-1 sequences correlated to sequence changes in LINE-1 elements at ZNF507's binding site. To gain further insight into ZNF146 and ZNF507 function, we disrupt their expression in HEK293 cells using CRISPR/Cas9 and perform RNA sequencing, finding modest gene expression changes in cells where ZNF507 has been disrupted. We further identify a physical interaction between ZNF507 and PRMT5, suggesting ZNF507 may target arginine methylation activity to LINE-1 sequences.

Non-Coding RNAs in Colorectal Cancer: Their Functions and Mechanisms

Colorectal cancer (CRC) is a common malignancy with high mortality. However, the molecular mechanisms underlying CRC remain unclear. Controversies over the exact functions of non-coding RNAs (ncRNAs) in the progression of CRC have been prevailing for multiple years. Recently, accumulating evidence has demonstrated the regulatory roles of ncRNAs in various human cancers, including CRC. The intracellular signaling pathways by which ncRNAs act on tumor cells have been explored, and in CRC, various studies have identified numerous dysregulated ncRNAs that serve as oncogenes or tumor suppressors in the process of tumorigenesis through diverse mechanisms. In this review, we have summarized the functions and mechanisms of ncRNAs (mainly lncRNAs, miRNAs, and circRNAs) in the tumorigenesis of CRC. We also discuss the potential applications of ncRNAs as diagnostic and prognostic tools, as well as therapeutic targets in CRC. This review details strategies that trigger the recognition of CRC-related ncRNAs, as well as the methodologies and challenges of studying these molecules, and the forthcoming clinical applications of these findings.

LncRNA-miRNA-mRNA regulatory axes in endometrial cancer: a comprehensive overview

INTRODUCTION

Recent research on tumorigenesis and progression has opened up an array of novel molecular mechanisms in the form of interactions between cellular non-coding RNAs (long non-coding RNA[lncRNA]/microRNA [miRNA]) and coding transcripts that regulate health and disease. Endometrial cancer (EC) is a prominent gynecological malignancy with a high incidence rate and poorly known etiology and prognostic factors that hinder the success of disease management. The emerging role of lncRNA-miRNA-mRNA interactions and their dysregulation in the pathophysiology of EC has been elucidated in many recent studies.

METHODS

A thorough literature review was conducted to explore information about lncRNA-miRNA-mRNA axes in EC.

RESULTS

Several lncRNAs act as molecular sponges that sequester various tumor suppressor miRNAs to inhibit their function, leading to the dysregulation of their target mRNA transcripts that contribute to the EC regulation.

CONCLUSIONS

This review summarizes these networks of molecular mechanisms and their contribution to different aspects of endometrial carcinogenesis, leading to a better conceptualization of the molecular pathways that underlie the disease and helping establish novel diagnostic biomarkers and therapeutic intervention points to aid the curative intent of EC.

Identification of lncRNA-miRNA-mRNA Networks Linked to Non-small Lung Cancer Resistance to Inhibitors of Epidermal Growth Factor Receptor

Background: Tyrosine kinase inhibitors that act against epidermal growth factor receptor (EGFR) show strong efficacy against non-small cell lung cancer (NSCLC) involving mutated EGFRs. However, most such patients eventually develop resistance to EGFR-TKIs. Numerous researches have reported that messenger RNAs (mRNAs) and non-coding RNAs (ncRNAs) may be involved in EGFR-TKI resistance, but the comprehensive expression profile and competitive endogenous RNA (ceRNA) regulatory network between mRNAs and ncRNAs in EGFR-TKI resistance of NSCLC are incompletely known. We aimed to define a ceRNA regulatory network linking mRNAs and non-coding RNAs that may mediate this resistance.

Methods: Using datasets GSE83666, GSE75309 and GSE103352 from the Gene Expression Omnibus, we identified long non-coding RNAs (lncRNAs), microRNAs (miRNAs) and mRNAs differentially expressed between NSCLC cells that were sensitive or resistant to EGFR-TKIs. The potential biological functions of the corresponding differentially expressed genes were analyzed based KEGG pathways. We combined interactions among lncRNAs, miRNAs and mRNAs in the RNAInter database with KEGG pathways to generate transcriptional regulatory ceRNA networks associated with NSCLC resistance to EGFR-TKIs. Kaplan-Meier analysis was used to assess the ability of core ceRNA regulatory sub-networks to predict the progression-free interval and overall survival of NSCLC. The expression of two core ceRNA regulatory sub-networks in NSCLC was validated by quantitative real-time PCR.

Results: We identified 8,989 lncRNAs, 1,083 miRNAs and 3,191 mRNAs that were differentially expressed between patients who were sensitive or resistant to the inhibitors. These DEGs were linked to 968 biological processes and 31 KEGG pathways. Pearson analysis of correlations among the DEGs of lncRNAs, miRNAs and mRNAs identified 12 core ceRNA regulatory sub-networks associated with resistance to EGFR-TKIs. The two lncRNAs ABTB1 and NPTN with the hsa-miR-150–5p and mRNA SERPINE1 were significantly associated with resistance to EGFR-TKIs and survival in NSCLC. These lncRNAs and the miRNA were found to be down-regulated, and the mRNA up-regulated, in a resistant NSCLC cell line relative to the corresponding sensitive cells.

Conclusion: In this study, we provide new insights into the pathogenesis of NSCLC and the emergence of resistance to EGFR-TKIs, based on a lncRNA-miRNA-mRNA network.

KCNQ1OT1: An Oncogenic Long Noncoding RNA

Long noncoding RNAs (lncRNAs) are transcripts greater than 200 nucleotides that do not code for proteins but regulate gene expression. Recent studies indicate that lncRNAs are involved in the modulation of biological functions in human disease. KCNQ1 Opposite Strand/Antisense Transcript 1 (KCNQ1OT1) encodes a lncRNA from the opposite strand of KCNQ1 in the CDKN1C/KCNQ1OT1 cluster that is reported to play a vital role in the development and progression of cancer. KCNQ1OT1 regulates cancer cell proliferation, cell cycle, migration and invasion, metastasis, glucose metabolism, and immune evasion. The aberrant expression of KCNQ1OT1 in cancer patients is associated with poor prognosis and decreased survival. This review summarizes recent literature related to the biological functions and molecular mechanisms of KCNQ1OT1 in various human cancers, including colorectal, bladder, breast, oral, melanoma, osteosarcoma, lung, glioma, ovarian, liver, acute myeloid leukemia, prostate, and gastric. We also discuss the role of KCNQ1OT1 as a promising diagnostic biomarker and a novel therapeutic target in human cancers.

LncRNA MSC-AS1 Promotes Colorectal Cancer Progression by Regulating miR-325/TRIM14 Axis

Background

LncRNA MSC-AS1 has been reported to be a tumor promoter in hepatocellular carcinoma. However, the function of MSC-AS1 in colorectal cancer (CRC) has not been elucidated. It is designed to study the expression level of MSC-AS1 and investigate its biological effect on the progression of CRC.

Methods

The expression patterns of MSC-AS1, miR-325, and TRIM14 were explored by RT-qPCR in CRC tissues and cells. The protein expression of TRIM14 was tested by Western blot assay. The association between MSC-AS1 expression and clinicopathological data was analyzed by chi-squared test. CCK-8 assay, colony formation, and Transwell assay were used to investigate the effect of MSC-AS1 on cell growth, invasion, and migration in CRC cells. The correlations among MSC-AS1, miR-325, and TRIM14 were analyzed by Pearson's correlation coefficient analysis.

Results

We found that MSC-AS1 and TRIM14 were upregulated in CRC tissues, while miR-325 was downregulated in CRC tissues. Functional experiments demonstrated that MSC-AS1 knockdown inhibited cell proliferation, migration, and invasion abilities in CRC cells. Additionally, miR-325 was proved to be a target miRNA of MSC-AS1, and TRIM14 might be a downstream gene of miR-325. Besides that, MSC-AS1 counteracted the inhibitory effect of miR-325 on the cell progression and TRIM14 expression.

Conclusion

Our results indicated that MSC-AS1 facilitated CRC progression by sponging miR-325 to upregulate TRIM14 expression. We suggested that MSC-AS1 might be a potential lncRNA-target for CRC therapy.