LncRNA SNHG12 promotes cell growth and inhibits cell apoptosis in colorectal cancer cells

LncRNA SNHG12 promotes cell proliferation and inhibits apoptosis of granulosa cells in polycystic ovarian syndrome by sponging miR-129 and miR-125b

BACKGROUND

Polycystic ovarian syndrome (PCOS) is the most common endocrine disease in women of childbearing age which is often associated with abnormal proliferation or apoptosis of granulosa cells (GCs). Studies proved that long non-coding RNA SNHG12 (lncRNA SNHG12) is significantly increased in ovarian cancer and cervical cancer patients and cells. The inhibition of lncRNA SNHG12 restrains the proliferation, migration, and invasion in tumor cells.

OBJECTIVE

This study explores the role of lncRNA SNHG12 in the apoptosis of GCs in PCOS and the underlying regulated mechanism.

METHODS

In this study, the injection of dehydroepiandrosterone (DHEA) successfully induced the PCOS model in SD rats. The human granulosa-like tumor cell line KGN was incubated with insulin to assess the effects of lncRNA SNHG12 on GC proliferation and apoptosis.

RESULTS

Overexpression of lncRNA SNHG12 influenced the body weight, ovary weight, gonadal hormone, and pathological changes, restrained the expressions of microRNA (miR)-129 and miR-125b, while downregulation of lncRNA SNHG12 exerted the opposite effects in PCOS rats. After silencing lncRNA SNHG12 in cells, the cell viability and proliferation were lessened whereas apoptosis of cells was increased. A loss-of-functions test was implemented by co-transfecting miR-129 and miR-125b inhibitors into lncRNA SNHG12-knocking down cells to analyze the effects on cell viability and apoptosis. Next, the existence of binding sites of SNHG12 and miR-129/miR-125b was proved based on the pull-down assay.

CONCLUSION

lncRNA SNHG12 might be a potential regulatory factor for the development of PCOS by sponging miR-129 and miR-125b in GCs.

Functional role of lncRNAs in gastrointestinal malignancies: the peculiar case of small nucleolar RNA host gene family

Long noncoding RNAs (lncRNAs) play crucial roles in normal physiology and are often de-regulated in disease states such as cancer. Recently, a class of lncRNAs referred to as the small nucleolar RNA host gene (SNHG) family have emerged as important players in tumourigenesis. Here, we discuss new findings describing the role of SNHGs in gastrointestinal tumours and summarize the three main functions by which these lncRNAs promote carcinogenesis, namely: competing with endogenous RNAs, modulating protein function, and regulating epigenetic marking. Furthermore, we discuss how SNHGs participate in different hallmarks of cancer, and how this class of lncRNAs may serve as potential biomarkers in cancer diagnosis and therapy.

Identification of molecular subtypes and a prognostic signature based on m6A/m5C/m1A-related genes in lung adenocarcinoma

Lung cancer, specifically the histological subtype lung adenocarcinoma (LUAD), has the highest global occurrence and fatality rate. Extensive research has indicated that RNA alterations encompassing m6A, m5C, and m1A contribute actively to tumorigenesis, drug resistance, and immunotherapy responses in LUAD. Nevertheless, the absence of a dependable predictive model based on m6A/m5C/m1A-associated genes hinders accurately predicting the prognosis of patients diagnosed with LUAD. In this study, we collected patient data from The Cancer Genome Atlas (TCGA) and identified genes related to m6A/m5C/m1A modifications using the GeneCards database. The "ConsensusClusterPlus" R package was used to produce molecular subtypes by utilizing genes relevant to m6A/m5C/m1A identified through differential expression and univariate Cox analyses. An independent prognostic factor was identified by constructing a prognostic signature comprising six genes (SNHG12, PABPC1, IGF2BP1, FOXM1, CBFA2T3, and CASC8). Poor overall survival and elevated expression of human leukocyte antigens and immune checkpoints were correlated with higher risk scores. We examined the associations between the sets of genes regulated by m6A/m5C/m1A and the risk model, as well as the immune cell infiltration, using algorithms such as ESTIMATE, CIBERSORT, TIMER, ssGSEA, and exclusion (TIDE). Moreover, we compared tumor stemness indices (TSIs) by considering the molecular subtypes related to m6A/m5C/m1A and risk signatures. Analyses were performed based on the risk signature, including stratification, somatic mutation analysis, nomogram construction, chemotherapeutic response prediction, and small-molecule drug prediction. In summary, we developed a prognostic signature consisting of six genes that have the potential for prognostication in patients with LUAD and the design of personalized treatments that could provide new versions of personalized management for these patients.

LncRNA SNHG12: A budding star in human diseases

Small nucleolar RNA host gene 12 (SNHG12) is a long non-coding RNA (lncRNA) that contributes in a variety of human pathologies. This lncRNAs acts as molecular sponge for various miRNAs, namely miR-200c-5p, miR-129-5p, miR-30a-3p, miR-195, miR-133b, miR-199a/b-5p, miR-320b, miR-16, miR-15a, miR-218-5p, miR-320 and a number of other miRNAs. Through this mechanism, SNHG12 can affect activity of HIF-1α, Wnt/β-catenin, VEGF, PI3K/AKT/mTOR, PTEN, NF-κB and ERK-1/2 signaling. SNHG12 can affect pathogenesis of several disorders, including those arising from genitourinary, gastrointestinal, pulmonary, central nervous and cardiovascular systems. These effects have been best characterized in the context of cancer where it can be used as a possible diagnostic and prognostic marker. In order to summarize the role of this lncRNA in human disorders, particularly cancer and highlight its potential application in biomedical studies, we designed the current review. We also emphasized on its diagnostic and prognostic roles.

Role of non-coding RNAs as new therapeutic targets in regulating the EMT and apoptosis in metastatic gastric and colorectal cancers

Colorectal cancer (CRC) and gastric cancer (GC), are the two most common cancers of the gastrointestinal tract, and are serious health concerns worldwide. The discovery of more effective biomarkers for early diagnosis, and improved patient prognosis is important. Non-coding RNAs (ncRNAs), including microRNAs (miRNAs) and long non-coding RNAs (lncRNAs), can regulate cellular processes such as apoptosis and the epithelial-mesenchymal transition (EMT) leading to progression and resistance of GC and CRC tumors. Moreover these pathways (apoptosis and EMT) may serve as therapeutic targets, to prevent metastasis, and to overcome drug resistance. A subgroup of ncRNAs is common to both GC and CRC tumors, suggesting that they might be used as biomarkers or therapeutic targets. In this review, we highlight some ncRNAs that can regulate EMT and apoptosis as two opposite mechanisms in cancer progression and metastasis in GC and CRC. A better understanding of the biological role of ncRNAs could open up new avenues for the development of personalized treatment plans for GC and CRC patients.

A comprehensive insight into the role of small nucleolar RNAs (snoRNAs) and SNHGs in human cancers

Long non-coding RNAs (lncRNAs), which comprise most non-coding RNAs (ncRNAs), have recently become a focus of cancer research. How many functional ncRNAs exist is still a matter of debate. Although insufficient evidence supports that most lncRNAs function as transcriptional by-products, it is widely known that an increasing number of lncRNAs play essential roles in cells. Small nucleolar RNAs (snoRNAs), 60-300 nucleotides in length, have been better studied than long non-coding RNAs (lncRNAs) and are predominantly present in the nucleolus. Most snoRNAs are encoded in introns of protein- and non-protein-coding genes called small nucleolar RNA host genes (SNHGs). In this article, we explore the biology and characteristics of SNHGs and their role in developing human malignancies. In addition, we provide an update on the ability of these snoRNAs to serve as prognostic and diagnostic variables in various forms of cancer.

Association between small nucleolar RNA host gene expression and survival outcome of colorectal cancer patients: A meta-analysis based on PRISMA and bioinformatics analysis

Introduction

Growing evidence shows that long non-coding RNA small nucleolar RNA host genes (lncRNA SNHGs) enact an pivotal regulatory roles in the shorter survival outcome of colorectal cancer (CRC). However, no research has systematically evaluated the correlation among lncRNA SNHGs expression and survival outcome of CRC. This research indented to screen whether exist potential prognostic effect of lncRNA SNHGs in CRC patientss using comprehensive review and meta-analysis.

Methods

Systematic searches were performed from the six relevant databases from inception to October 20, 2022. The quality of published papers was evaluated in details. We pooled the hazard ratios (HR) with 95% confidence interval (CI) through direct or indirect collection of effect sizes, and odds ratios (OR) with 95% CI by collecting effect sizes within articles. Detailed downstream signaling pathways of lncRNA SNHGs were summarized in detail.

Results

25 eligible publications including 2,342 patients were finally included to appraise the association of lncRNA SNHGs with prognosis of CRC. Elevated lncRNA SNHGs expression was revealed in colorectal tumor tissues. High lncSNHG expression means bad survival prognosis in CRC patients (HR=1.635, 95% CI: 1.405-1.864, P<0.001). Additionally, high lncRNA SNHGs expression was inclined to later TNM stage (OR=1.635, 95% CI: 1.405-1.864, P<0.001), distant lymph node invasion, distant organ metastasis, larger tumor diameter and poor pathological grade. Begg's funnel plot test using the Stata 12.0 software suggested that no significant heterogeneity was found.

Conclusion

Elevated lncRNA SNHGs expression was revealed to be positively correlated to discontented CRC clinical outcome and lncRNA SNHG may act as a potential clinical prognostic index for CRC patients.

LncRNA OIP5-AS1 Mitigates Bupivacaine-Induced Neurotoxicity in Dorsal Root Ganglion Neurons Through Regulating NFAT5 Expression via Sponging miR-34b

Bupivacaine (BUP), which is widely used in anesthesia, can cause neurotoxicity and neurological abnormalities. This work intended to study the function of long non-coding RNA (lncRNA) OIP5 antisense RNA 1 (OIP5-AS1) in BUP-triggered neurotoxicity. OIP5-AS1, microRNA (miR)-34b, and nuclear factor of activated T cells 5 (NFAT5) levels were examined via real-time quantitative PCR (RT-qPCR). Cell proliferation, caspase-3 activity, and apoptosis were assessed via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT), caspase-3 activity, and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assays. The regulatory relationships between miR-34b and OIP5-AS1 or NFAT5 were validated via RNA binding protein immunoprecipitation (RIP) and dual-luciferase reporter assays. Our data demonstrated that OIP5-AS1 and NFAT5 levels were downregulated and miR-34b was upregulated upon exposure to BUP. Functional assays implied that the OIP5-AS1 deficiency impeded cell proliferation and enhanced the apoptosis of DRG neurons, while OIP5-AS1 addition reversed these changes. Moreover, OIP5-AS1 could bind to miR-34b and OIP5-AS1 regulated BUP-induced neurotoxicity via miR-34b. Besides, miR-34b could directly interact with NFAT5. Augmentation of miR-34b impeded cell proliferation and expedited the apoptosis and caspase-3 activity, while NFAT5 addition neutralized these impacts. Finally, it was verified that OIP5-AS1 could upregulate NFAT5 through sponging miR-34b. In sum, our results disclosed that OIP5-AS1 ameliorated BUP-caused neurotoxicity via regulating the miR-34b/NFAT5 axis, suggesting that OIP5-AS1 might be a promising therapeutic target for the treatment of BUP-induced neurotoxicity.

Long noncoding RNA CLAN promotes lymphangiogenesis in the colorectal carcinoma

Metastasis is the main cause of colorectal cancer (CRC)-related death and lymph node plays a vital role in this process. Long noncoding RNAs (lncRNAs) are emerging as an important factor of biological progress in cancers. However, lncRNAs related to CRC metastasis was rarely reported.CLAN expression data of tumor tissues and normal tissues were obtained from GEPIA database and 23 paired tumor and normal samples of patients. CLAN expression of 85 patients was carried out with RNA extracted from FFPE samples and quantified with qRT-PCR. Patients' clinical features were collected from department of Pathology of the Affiliated Hospital of Southwest Medical University. Immunohistochemistry staining was used to detect the metastasis-related proteins.CLAN was highly expressed in tumor tissues. And the expression level was not correlated with age, gender, differentiation, and location of CRC patients. Also, CLAN expression did not correlated with budding, LVI, and TILs. However, CLAN expression was strongly associated with lymph node metastasis and higher TNM stage. CLAN changed the lymphatic vessel density by promoting lymphangiogenesis but CLAN did not affect the blood vessel density.CLAN was a unique lncRNA that promoted lymphangiogenesis to accelerate CRC metastasis. CLAN might play a unique role in tumor early dissemination through lymphatic vessel.

Systematic pan-cancer analysis on the expression and role of regulator of chromatin condensation 1/small nucleolar RNA host gene 3/small nucleolar RNA host gene 12

Regulator of chromatin condensation 1 (RCC1) is the major guanine nucleotide exchange factor of RAN GTPase, which plays a key role in various biological processes such as cell cycle and DNA damage repair. Small nucleolar RNA host gene 3 (SNHG3) and small nucleolar RNA host gene12 are long-stranded non-coding RNAs (lncRNAs) and are located on chromatin very close to the sequence of Regulator of chromatin condensation 1. Many studies have shown that they are aberrantly expressed in tumor tissues and can affect the proliferation and viability of cancer cells. Although the effects of Regulator of chromatin condensation 1/small nucleolar RNA host gene 3/small nucleolar RNA host gene12 on cellular activity have been reported, respectively, their overall analysis on the pan-cancer level has not been performed. Here, we performed a comprehensive analysis of Regulator of chromatin condensation 1/small nucleolar RNA host gene 3/small nucleolar RNA host gene12 in 33 cancers through the Cancer Genome Atlas and Gene Expression Database. The results showed that Regulator of chromatin condensation 1/small nucleolar RNA host gene 3/small nucleolar RNA host gene12 were highly expressed in a variety of tumor tissues compared to normal tissues. The expression of Regulator of chromatin condensation 1/small nucleolar RNA host gene 3/small nucleolar RNA host gene12 in BRCA, LGG and LIHC was associated with TP53 mutations. In addition, Regulator of chromatin condensation 1/small nucleolar RNA host gene 3/small nucleolar RNA host gene12 expression was closely associated with the prognosis of patients with multiple tumors. Immunocorrelation analysis indicated that Regulator of chromatin condensation 1/small nucleolar RNA host gene 3/small nucleolar RNA host gene12 showed a correlation with multiple immune cell infiltration. The results of enrichment analysis suggested that Regulator of chromatin condensation 1/small nucleolar RNA host gene 3/small nucleolar RNA host gene12 was involved in the regulation of cell cycle, apoptosis and other pathways. We found that these effects were mainly mediated by Regulator of chromatin condensation 1, while the trend of small nucleolar RNA host gene 3/small nucleolar RNA host gene12 regulation was also consistent with regulator of chromatin condensation 1. The important role played by Regulator of chromatin condensation 1 in tumor diseases was further corroborated by the study of adjacent lncRNAs.These findings provide new and comprehensive insights into the role of Regulator of chromatin condensation 1/small nucleolar RNA host gene 3/small nucleolar RNA host gene12 in tumor development and show their potential as clinical monitoring and therapy.

The role of lncRNA-mediated ceRNA regulatory networks in pancreatic cancer

Non-coding RNAs (ncRNAs), which occupy the vast majority of human transcripts are known for their inability to encode proteins. NcRNAs consist of a diverse range of RNA species, including long non-coding RNAs (lncRNAs), which have significant meaning for epigenetic modification, post-transcriptional regulation of target genes, molecular interference, etc. The dysregulation of ncRNAs will mediate the pathogenesis of diverse human diseases, like cancer. Pancreatic cancer, as one of the most lethal malignancies in the digestive system that is hard to make a definite diagnosis at an early clinicopathological stage with a miserable prognosis. Therefore, the identification of potential and clinically applicable biomarker is momentous to improve the overall survival rate and positively ameliorate the prognosis of patients with pancreatic carcinoma. LncRNAs as one kind of ncRNAs exert multitudinous biological functions, and act as molecular sponges, relying on microRNA response elements (MREs) to competitively target microRNAs (miRNAs), thereby attenuating the degradation or inhibition of miRNAs to their own downstream protein-coding target genes, also thus regulating the initiation and progression of neoplasms. LncRNAs, which emerge aforementioned function are called competing endogenous RNAs (ceRNAs). Consequently, abundant research of lncRNAs as potential biomarkers is of critical significance for the molecular diagnosis, targeted therapy, as well as prognosis monitoring of pancreatic cancer.

Small nucleolar RNAs and SNHGs in the intestinal mucosal barrier: Emerging insights and current roles

BACKGROUND

Previous studies have focused on the involvement of small nucleolar RNAs (snoRNAs) and SNHGs in tumor cell proliferation, apoptosis, invasion, and metastasis via multiple pathways, including phosphatidylinositol-3-kinase/protein kinase B (PI3K/AKT), Wnt/β catenin, and mitogen-activated protein kinase (MAPK). These molecular mechanisms affect the integrity of the intestinal mucosal barrier.

AIM OF REVIEW

Current evidence regarding snoRNAs and SNHGs in the context of the mucosal barrier and modulation of homeostasis is fragmented. In this review, we collate the established information on snoRNAs and SNHGs as well as discuss the major pathways affecting the mucosal barrier.

KEY SCIENTIFIC CONCEPTS OF REVIEW

Intestinal mucosal immunity, microflora, and the physical barrier are altered in non-neoplastic diseases such as inflammatory bowel diseases. Dysregulated snoRNAs and SNHGs may impact the intestinal mucosal barrier to promote the pathogenesis and progression of multiple diseases. SnoRNAs or SNHGs has been shown to be associated with poor disease behaviors, indicating that they may be exploited as prognostic biomarkers. Additionally, clarifying the complicated interactions between snoRNAs or SNHGs and the mucosal barrier may provide novel insights for the therapeutic treatment targeting strengthen the intestinal mucosal barrier.

The various regulatory functions of long noncoding RNAs in apoptosis, cell cycle, and cellular senescence

Long noncoding RNAs (lncRNAs) are a group of noncoding cellular RNAs involved in significant biological phenomena such as differentiation, cell development, genomic imprinting, adjusting the enzymatic activity, regulating chromosome conformation, apoptosis, cell cycle, and cellular senescence. The misregulation of lncRNAs interrupting normal biological processes has been implicated in tumor formation and metastasis, resulting in cancer. Apoptosis and cell cycle, two main biological phenomena, are highly conserved and intimately coupled mechanisms. Hence, some cell cycle regulators can influence both programmed cell death and cell division. Apoptosis eliminates defective and unwanted cells, and the cell cycle enables cells to replicate themselves. The improper regulation of apoptosis and cell cycle contributes to numerous disorders such as neurodegenerative and autoimmune diseases, viral infection, anemia, and mainly cancer. Cellular senescence is a tumor-suppressing response initiated by environmental and internal stress factors. This phenomenon has recently attained more attention due to its therapeutic implications in the field of senotherapy. In this review, the regulatory roles of lncRNAs on apoptosis, cell cycle, and senescence will be discussed. First, the role of lncRNAs in mitochondrial dynamics and apoptosis is addressed. Next, the interaction between lncRNAs and caspases, pro/antiapoptotic proteins, and also EGFR/PI3K/PTEN/AKT/mTORC1 signaling pathway will be investigated. Furthermore, the effect of lncRNAs in the cell cycle is surveyed through interaction with cyclins, cdks, p21, and wnt/β-catenin/c-myc pathway. Finally, the function of essential lncRNAs in cellular senescence is mentioned.

Long non-coding RNA TMPO-AS1 facilitates the progression of colorectal cancer cells via sponging miR-98-5p to upregulate BCAT1 expression

BACKGROUND AND AIM

Colorectal cancer, as a common malignant carcinoma in the gastrointestinal tract, has a high mortality globally. However, the specific molecular mechanisms of long non-coding RNA (lncRNA) thymopoietin antisense transcript 1 (TMPO-AS1) in colorectal cancer were unclear.

METHODS

We tested the expression level of TMPO-AS1 via qRT-PCR in colorectal cancer cells, while the protein levels of branched chain amino acid transaminase 1 (BCAT1) and the stemness-related proteins were evaluated by western blot analysis. Colony formation, EdU staining, TUNEL, flow cytometry, and sphere formation assays were to assess the biological behaviors of colorectal cancer cells. Then, luciferase reporter, RIP, and RNA pull down assay were applied for confirming the combination between microRNA-98-5p (miR-98-5p) and TMPO-AS1/BCAT1.

RESULTS

TMPO-AS1 was aberrantly expressed at high levels in colorectal cancer cells. Silenced TMPO-AS1 restrained cell proliferation and stemness and promoted apoptosis oppositely, while overexpressing TMPO-AS1 exerted the adverse effects. Furthermore, miR-98-5p was proven to a target of TMPO-AS1 inhibit cell progression in colorectal cancer. Additionally, BCAT1 was proved to enhance cell progression as the target of miR-98-5p, and it offset the effect of silenced TMPO-AS1 on colorectal cancer cells.

CONCLUSION

TMPO-AS1 promotes the progression of colorectal cancer cells via sponging miR-98-5p to upregulate BCAT1 expression.

Non-coding RNA-associated competitive endogenous RNA regulatory networks: Novel diagnostic and therapeutic opportunities for hepatocellular carcinoma

Hepatocellular carcinoma (HCC), as the most prevalent liver malignancy, is annually diagnosed in more than half a million people worldwide. HCC is strongly associated with hepatitis B and C viral infections as well as alcohol abuse. Obesity and nonalcoholic fatty liver disease (NAFLD) also significantly enhance the risk of liver cancer. Despite recent improvements in therapeutic approaches, patients diagnosed in advanced stages show poor prognosis. Accumulating evidence provides support for the regulatory role of non-coding RNAs (ncRNAs) in cancer. There are a variety of reports indicating the regulatory role of microRNAs (miRNAs) in different stages of HCC. Long non-coding RNAs (LncRNAs) exert their effects by sponging miRNAs and controlling the expression of miRNA-targeted genes. Circular RNAs (circRNAs) perform their biological functions by acting as transcriptional regulators, miRNA sponges and protein templates. Diverse studies have illustrated that dysregulation of competing endogenous RNA networks (ceRNETs) is remarkably correlated with HCC-causing diseases such as chronic viral infections, nonalcoholic steatohepatitis and liver fibrosis/cirrhosis. The aim of the current article was to provide an overview of the role and molecular mechanisms underlying the function of ceRNETs that modulate the characteristics of HCC such as uncontrolled cell proliferation, resistance to cell death, metabolic reprogramming, immune escape, angiogenesis and metastasis. The current knowledge highlights the potential of these regulatory RNA molecules as novel diagnostic biomarkers and therapeutic targets in HCC.

ESRG, LINC00518 and PWRN1 are newly-identified deregulated lncRNAs in colorectal cancer

Colorectal cancer is the 2nd leading cause of death in humans because of cancer. This rank of death could be due to the high rate of incidence from one hand, and the lack of sufficient diagnostic and therapeutic approaches from the other hand. Thus, molecular tools have been emerging as the potential biomarker to improve the early diagnosis and therapeutic management that subsequently could lead to the heightened survival rate of colorectal cancer patients. Long non-coding RNA (lncRNAs) have shown promising capabilities to be used in clinics. The profiling methods could identify novel aberrantly expressed lncRNAs in colorectal cancer. We, thus, performed a comprehensive and unbiased approach to shortlist the dysregulated lncRNAs based on the colon adenocarcinoma TCGA data. An unbiased in silico method was used to rank the yet to profiled lncRNAs in colorectal cancer. qPCR was used to measure the expression level of selected lncRNAs. Our results nominated ESRG, LINC00518, PWRN1, and TTTY14 lncRNAs as the top-hit novel lncRNAs with aberrant expression in colon cancer. The qPCR method was used to profile these lncRNAs that showed the up-regulation of ESRG and LINC00518, and down-regulation of TTTY14 in thirty paired colorectal cancer specimens. The statistical analyses demonstrated that ESRG, LINC00518 and PWRN1 could distinguish the tumor from normal samples. Moreover, ESRG showed a negative correlation with the overall survival of patients. These diagnostic and prognostic results suggest that profiling ESRG, LINC00518 and PWRN1 s may have implications in clinics.

LncRNA ASB16-AS1 drives proliferation, migration, and invasion of colorectal cancer cells through regulating miR-185-5p/TEAD1 axis

As a common malignant tumor, colorectal cancer (CRC) has a high incidence. Recent investigations have suggested that although great improvement has been achieved in the survival rate of early-stage CRC patients, the overall survival rate remains low. Mounting reports have proved that lncRNAs take part in the development of various cancers and possess the regulatory functions in cancers. For example, ASB16 antisense RNA 1 (ASB16-AS1) is a poorly researched novel lncRNA whose specific functions in CRC are still unknown. In our research, we discovered that ASB16-AS1 was with high expression in CRC cells. In addition, ASB16-AS1 silencing restrained the proliferation, migration, invasion, and stemness while accelerating cell apoptosis of CRC cells. Mechanism experiments were applied to explore the regulatory mechanism of ASB16-AS1. It turned out that miR-185-5p could interact with ASB16-AS1 and inhibited the progression of CRC cells. TEAD1 (TEA domain transcription factor1) - a major effector of the Hippo signaling was proved to serve as the target of miR-185-5p and promote CRC development. In short, ASB16-AS1 drove the progression of CRC through the regulation of miR-185-5p/TEAD1 axis.

Highly expressed TLX1NB and NPSR1-AS1 lncRNAs could serve as diagnostic tools in colorectal cancer

Colorectal cancer is the main cause of human death due to cancer. This fact could be due to the insufficiency of early diagnosis or poor therapeutic strategies. Various molecular tools have been utilized in studies to assess their potentials as diagnostic biomarkers or determining factors in precision medicine. Among these molecules, long non-coding RNAs (lncRNA) have been emerging as accurate and potent transcripts to improve the detection of cancer. The overexpressed lncRNAs could also be deeply studied as the molecules for the targeted therapy in different malignancies, in particular colorectal cancer. Thus, we utilized an unbiased approach to select the up-regulated lncRNAs in colon adenocarcinoma via analyzing the TCGA dataset. Then, we validated the overexpression of two first-ranked lncRNAs, i.e., NPSR1-AS1 and TLX1NB, in our in-house colorectal cancer samples as compared to the paired adjacent normal tissues. The analyses revealed that these lncRNAs could significantly distinguish the tumor against the normal samples. The results may have implications in the early diagnosis and targeted therapy of colorectal cancer.

Long noncoding RNA SNHG12 is a potential diagnostic and prognostic biomarker in various tumors

BACKGROUND

Tumors are the second most common cause of death in humans worldwide, second only to cardiovascular and cerebrovascular diseases. Although methods and techniques for the treatment of tumors continue to improve, the effect is not satisfactory. These may lack effective therapeutic targets. This study aimed to evaluate the value of SNHG12 as a biomarker in the prognosis and clinical characteristics of various cancer patients.

METHODS

We analyzed SNHG12 expression and plotted the survival curves of all cancer samples in the TCGA database using the GEPIA tool. Then, we searched for eligible papers up to April 1, 2019, in databases. Next, the data were extracted from studies examining SNHG12 expression, overall survival and clinicopathological features in patients with malignant tumors. We used Review Manager 5.3 and Stata 15 software to analyze the statistical data.

RESULTS

In the TCGA database, abnormally high expression of SNHG12 in tumor samples indicates that the patient has a poor prognosis. Results of meta-analysis is that SNHG12 high expression is related to low overall survival (HR = 2.72, 95% CI = 1.95-3.8, P < 0.00001), high tumor stage (OR = 3.94, 95% CI = 2.80-5.53, P < 0.00001), high grade (OR = 2.04, 95% CI = 1.18-3.51, P = 0.01), distant metastasis (OR = 2.20, 95% CI = 1.40-3.46, P = 0.0006), tumor size (OR = 2.79, 95% CI = 1.89-4.14, P < 0.00001), and lymph node metastasis (OR = 2.66, 95% CI = 1.65-4.29, P < 0.0001).

CONCLUSIONS

Our study confirmed that the high expression level of SNHG12 is closely related to the clinicopathological characteristics and prognosis of patients and is a new predictive biomarker for various cancer patients.

Targeting NUFIP1 Suppresses Growth and Induces Senescence of Colorectal Cancer Cells

NUFIP1 is an RNA-binding protein that interacts with fragile X mental retardation protein (FMRP) in the messenger ribonucleoprotein particle (mRNP). We previously showed that NUFIP1 was upregulated in colorectal cancer (CRC), but how the protein may contribute to the disease and patient prognosis is unknown. Here we combine database analysis, microarray, quantitative PCR, and immunohistochemistry of patients' samples to confirm our previous findings on NUFIP1 overexpression in CRC, and to reveal that increased expression of NUFIP1 in CRC tissues correlated with worse overall, recurrence-free, event-free and disease-free survival in patients, as well as with more advanced CRC clinicopathological stage. Loss of function analysis demonstrated that NUFIP1 knockdown suppressed cell growth in vitro and in vivo, inhibited cell viability and survival, and induced cell cycle arrest and apoptosis in vitro, as well as up-regulated Bax and down-regulated Bcl-2 protein expression. In addition, as a natural anticancer triterpene from various fruits and vegetables, ursolic acid (UA) treatment suppressed cell proliferation, down-regulated NUFIP1 protein expression, and further enhanced the effects of NUFIP1 knockdown in CRC cells in vitro. NUFIP1 knockdown up-regulated the expression of 136 proteins, down-regulated the expression of 41 proteins, and enriched multiple signaling pathways including the senescence-associated heterochromatin foci (SAHF) pathway. Furthermore, NUFIP1 knockdown enhanced the expression of senescence-associated-β-galactosidase (SA-β-gal), the SAHF markers HP1γ and trimethylation (H3k9me3), and the senescence-related protein HMGA2, as well as both p53 and its downstream p21 protein expression. Our findings suggest that NUFIP1 is overexpressed in CRC and correlates with disease progression and poor patient survival. NUFIP1 may exert oncogenic effects partly by altering senescence. UA may show potential to treat CRC by down-regulating NUFIP1.

Role of microRNA-129 in cancer and non-cancerous diseases (Review)

An increasing number of studies indicate that microRNAs (miRNAs/miRs) are involved in diverse biological signaling pathways and play important roles in the progression of various diseases, including both oncological and non-oncological diseases. These small non-coding RNAs can block translation, resulting in a low expression level of target genes. miR-129 is an miRNA that has been the focus of considerable research in recent years. A growing body of evidence shows that the miR-129 family not only functions in cancer, including osteosarcoma, nasopharyngeal carcinoma, and ovarian, prostate, lung, breast and colon cancer, but also in non-cancerous diseases, including heart failure (HF), epilepsy, Alzheimer's disease (AD), obesity, diabetes and intervertebral disc degeneration (IVDD). It is therefore necessary to summarize current research progress on the role of miR-129 in different diseases. The present review includes an updated summary of the mechanisms of the miR-129 family in oncological and non-oncological diseases. To the best of our knowledge, this is the first review focusing on the role of miR-129 in non-cancerous diseases such as obesity, HF, epilepsy, diabetes, IVDD and AD.

LncRNA SNHG12 regulates the miR-101-3p/CUL4B axis to mediate the proliferation, migration and invasion of non-small cell lung cancer

Mounting evidence has shown that long noncoding RNAs (lncRNAs) play critical roles in carcinogenesis and tumor progression. SNHG12 has been identified in multiple types of malignant tumors. However, the role of SNHG12 in human non-small cell lung cancer (NSCLC) is poorly characterized, and the relevant underlying mechanism remains unclear. The expression levels of SNHG12, miR-101-3p, and CUL4B in collected human NSCLC tumor tissues and NSCLC cell lines were tested via qRT-PCR. Then, NSCLC cellular proliferation, migration and invasion were determined, followed by MTT, scratch and Transwell assays. Dual-luciferase reporter assays and RNA pulldown assays were adopted to explore the target site. Moreover, western blotting was performed to detect the relevant protein expression concerning the CUL4B/PI3K/AKT pathway. This study clarified that SNHG12 knockdown significantly reduced proliferation, migration, invasion and EMT of NSCLC cells. Our data indicated that SNHG12 targeted and negatively regulated miR-101-3p, and this depletion reversed the inhibitory effect of si-SNHG12 on NSCLC cells. Furthermore, CUL4B was confirmed as a functional target of miR-101-3p, and its knockdown resulted in a strong alleviation of the NSLCL cell phenotype, which was enhanced by the silencing of miR-101-3p. Mechanistically, we found that SNHG12 regulated miR-101-3p to modulate the PI3K/AKT pathway mediated by CUL4B.These observations suggested that lncRNA SNHG12-mediated miR-101-3p downregulation regulated the malignant phenotype of NSCLC cells by targeting CUL4B through the PI3K/AKT pathway, which may present a path to novel therapeutic strategies for NSCLC therapy.

LncRNA signature in colorectal cancer

Colorectal cancer (CRC) is among the most frequent cancers and is associated with high mortality particularly when being diagnosed in advanced stages. Although several environmental and intrinsic risk factors have been identified, the underlying cause of CRC is not clear in the majority of cases. Several studies especially in the recent decade have pointed to the role of epigenetic factors in this kind of cancer. Long non-coding RNAs (lncRNAs) as important contributors in the epigenetic mechanisms are involved in the initiation, progression and metastasis of CRC. Tens of oncogenic lncRNAs and a lower number of tumor suppressor lncRNAs have been recently identified to be dysregulated in CRC cells and tissues. Notably, expressions of a number of these transcripts have been dysregulated in serum samples of CRC patients, providing a non-invasive route for detection of this kind of cancer. The involvement of lncRNAs in the regulation of autophagy has provided them the ability to modulate response of CRC cells to chemotherapeutic modalities. In the current manuscript, we review the studies which evaluated the role of lncRNAs in the pathogenesis and progression of CRC to appraise their application as diagnostic/ prognostic markers.

SNHG12 promotes carcinogenesis of human renal cell cancer via functioning as a competing endogenous RNA and sponging miR-30a-3p

Small nucleolar RNA host gene 12 (SNHG12) has been indicated in the tumorigenesis of various human cancers, including clear cell renal cell carcinoma (ccRCC). However, the underlying mechanisms of SNHG12 driving progression of ccRCC remain incompletely understood. In the present study, we discovered that SNHG12 is up-regulated in ccRCC and that overexpression of SNHG12 predicted poor clinical outcome of ccRCC patients. SNHG12 knockdown notably inhibited proliferation and migration of RCC cells. Furthermore, we discovered that miR-30a-3p, a putative ccRCC inhibitor, was competitively sponged by SNHG12. Via the crosstalk network, SNHG12 was capable of up-regulating multiple target genes of miR-30a-3p, namely, RUNX2, WNT2 and IGF-1R, which have been identified to facilitate tumorigenesis of ccRCC. Taken together, our present study suggested a novel ceRNA network, in which SNHG12 could promote the malignancy of ccRCC although competitively binding with miR-30a-3p and consequently release the expression of its downstream cancer-related genes.

LncRNA SNHG12 contributes proliferation, invasion and epithelial-mesenchymal transition of pancreatic cancer cells by absorbing miRNA-320b

Pancreatic cancer is a kind of malignant carcinoma with high mortality, which is devoid of early diagnostic biomarker and effective therapeutic methods. Recently, long non-coding RNAs (lncRNAs) have been reported as a crucial role in regulating the development of various kinds of tumors. Here, we found lncRNA small nuclear RNA host gene 12 (SNHG12) is highly expressed in pancreatic cancer tissues and cell lines through qRT-PCR, which suggested that SNHG12 possibly accelerates the progression of pancreatic cancer. Further study revealed that SNHG12 promoted cancer cells growth and invasion via absorbing miR-320b. Flow cytometry and transwell chamber assay were utilized to verify the promoting effects on proliferation and invasion that SNHG12 acts in pancreatic cancer cells. Evidence that SNHG12 increased cell invasive ability through up-regulated EMT process was lately obtained by Western blotting assay. Consequently, we extrapolated that SNHG12/miR-320b could be invoked as a promising early diagnostic hallmark and therapeutic strategy for pancreatic cancer.

LncRNA SNHG12 promotes proliferation and epithelial mesenchymal transition in hepatocellular carcinoma through targeting HEG1 via miR-516a-5p

Hepatocellular carcinoma (HCC) is the most common cancer and its prognosis is poor due to metastasis and recurrence. EMT is associated with metastasis. A deep understanding of regulatory mechanism of EMT is critical. LncRNA is involved in regulation of various biological processes including EMT. This study aimed to investigate the regulatory signal axis among lncRNA SNHG12, miR-516a-5p and the target gene HEG1 during EMT. Cell cycle and apoptosis were analyzed by flow cytometry. Tumorigenesis was analyzed by clone formation assay. Wound healing assay and transwell assay was performed to detect migration and invasion, respectively. Interaction among SNHG12, miR-516a-5p and HEG1 were analyzed by dual luciferase assay and RIP assay. We also detected expression of RNA and protein by QPCR and western blotting. Finally, tumor growth was analyzed by tumorigenesis assay in vivo. Ki-67 and HEG1 level in tumor tissues was analyzed by IHC. SNHG12 and HEG1 were upregulated, miR-516a-5p was downregulated in HCC cell lines. SNHG12 could interact with and inhibit miR-516a-5p. MiR-516a-5p could interact with HEG1 and inhibit HEG1 expression. Knock down SNHG12 inhibited proliferation, migration, invasion, EMT and promoted apoptosis of HCC cells. Such effects were antagonized by inhibiting miR-516a-5p. SNHG12 overexpression lead to opposite results. Similar results were observed in mice. SNHG12 could promote EMT in HCC through targeting and inhibiting miR-516a-5p, which eventually upregulated HEG1 expression, in both cell and mice.

Long non-coding RNA SUMO1P3 promotes tumour progression by regulating cell proliferation and invasion in glioma

Gliomas account for 50% of primary brain tumours in the central nervous system. Small ubiquitin-like modifier 1 pseudogene 3 (SUMO1P3), a newly identified long non-coding RNA (lncRNA), serves an oncogenic role in various types of cancer. The aim of the present study was to investigate the effect of SUMO1P3 on glioma progression. The results demonstrated that SUMO1P3 expression was upregulated in glioma tissues and cell lines. Furthermore, SUMO1P3 was associated with a poor overall survival of patients with glioma. The results of the in vitro cell proliferation and flow cytometry assays demonstrated that SUMO1P3-knockdown suppressed cell proliferation and cell cycle. The results of the wound healing and Transwell assays demonstrated that SUMO1P3-knockdown significantly repressed cell migration and invasion. In addition, SUMO1P3 promoted glioma by regulating the expression levels of β-catenin, cyclin-D1, N-cadherin and E-cadherin. Overall, the results of the present study suggested that SUMO1P3 may act as an oncogene by regulating cell proliferation, cell cycle, cell migration and invasion in glioma, and may represent a novel diagnostic biomarker and therapeutic target for glioma.

A 6-lncRNA signature predicts prognosis of diffuse large B-cell lymphoma

Diffuse large B cell lymphoma (DLBCL) comprises distinct entities due to its heterogeneity. The currently used international prognostic index for DLBCL prognosis prediction is only based on clinical factors and cannot reflect the molecular mechanisms underlying its progression. Here, we aimed to establish a long noncoding RNAs (lncRNA)-based signature for DLBCL prognosis prediction. The data were retrieved from the Gene Expression Omnibus and The Cancer Genome Atlas database. After identifying the differentially expressed lncRNAs (DELs), univariate COX regression, LASSO regression, and stepwise regression analysis were performed to construct a 6-lncRNA risk score system. Kaplan-Meier survival presented that the high-risk group had a significantly poorer overall survival. Based on the risk score and clinical characters, a nomogram was established, which had better predictive accuracy than each factor alone. Finally, weighted gene co-expression network analysis showed that these lncRNAs might regulate immune response, metabolism process, and signal transduction to influence the outcome. Conclusively, our model and nomogram could be reliable prognostic tools for DLBCL patients.

Long Non-coding RNA H19 Augments Hypoxia/Reoxygenation-Induced Renal Tubular Epithelial Cell Apoptosis and Injury by the miR-130a/BCL2L11 Pathway

Acute kidney injury (AKI) is a severe kidney disease defined by partial or abrupt loss of renal function. Emerging evidence indicates that non-coding RNAs (ncRNAs), particularly long non-coding RNAs (lncRNAs), function as essential regulators in AKI development. Here we aimed to explore the underlying molecular mechanism of the lncRNA H19/miR-130a axis for the regulation of inflammation, proliferation, and apoptosis in kidney epithelial cells. Human renal proximal tubular cells (HK-2) were induced by hypoxia/reoxygenation to replicate the AKI model in vitro. After treatment, the effects of LncRNA H19 and miR-130a on proliferation and apoptosis of HK-2 cells were investigated by CCK-8 and flow cytometry. Meanwhile, the expressions of LncRNA H19, miR-130a, and inflammatory cytokines were detected by qRT-PCR, western blot, and ELISA assays. The results showed that downregulation of LncRNA H19 could promote cell proliferation, inhibit cell apoptosis, and suppress multiple inflammatory cytokine expressions in HK-2 cells by modulating the miR-130a/BCL2L11 pathway. Taken together, our findings indicated that LncRNA H19 and miR-130a might represent novel therapeutic targets and early diagnostic biomarkers for the treatment of AKI.

Long Noncoding RNA SNHG12 Promotes Prostate Tumor Occurrence and Progression via AKT Regulation

The small nucleolar RNA host gene 12 (SNHG12) has been reported to play an important role in the tumorigenesis and progression of PCa, but the functional underlying mechanism has not been studied clearly. We detected the expression level of SNHG12 in PCa tissues and matched adjacent normal tissues that were collected from 85 patients. Then, colony formation assays, MTT experiments, and flow cytometry were used to examine the effect of SNHG12 on proliferation, cell cycle distribution, and apoptosis of DU145 cells. Further, Transwell invasion assay was utilized to assess whether SNHG12 participates in PCa cell invasion and affects the secretion of VEGF secretion in DU145 cells. Finally, we investigated the effect of SNHG12 on tumor growth in vivo. We found that SNHG12 promoted cell proliferation and suppressed apoptosis in PCa cells, which suggests that SNHG12 is probably a novel PCa biomarker and therapy target of PCa.

Prognostic Value of Long Noncoding RNA SNHG12 in Various Carcinomas: A Meta-Analysis

Background

Numerous recent studies suggested that overexpression of the long noncoding RNA small nucleolar RNA host gene 12 (SNHG12) exhibited prooncogenic activity in multiple cancers. However, results regarding the prognostic value of SNHG12 in cancers still remained controversial. Therefore, we conducted a meta-analysis complemented with bioinformatics analysis to elucidate the clinical significance of SNHG12 in cancer patients.

Methods

PubMed, Embase, Cochrane Library, Chinese National Knowledge Infrastructure, Wanfang, and Weipu databases were searched for eligible studies until July 2020. Additionally, bioinformatics analysis was applied to verify the results of meta-analysis.

Results

Twenty-three related studies consisting of 1389 cancer patients were enrolled in the current meta-analysis. Elevated SNHG12 expression was found to be significantly associated with poor overall survival (OS) (HR = 1.81; 95% CI: 1.53-2.13; P < 0.001) and disease-free survival (DFS) (HR = 1.40; 95% CI: 1.12-1.76; P = 0.004) in multiple cancers, which were also verified by the results of bioinformatics analysis. Moreover, overexpression of SNHG12 was also related to clinicopathological characteristics including LNM, distant metastasis, high clinical stage, large tumor size, and poor tumor differentiation in diverse types of cancers.

Conclusion

The present findings indicated that SNHG12 might act as a novel biomarker for diagnosis or prognosis in human cancers.

Photodynamic therapy induces autophagy-mediated cell death in human colorectal cancer cells via activation of the ROS/JNK signaling pathway

Evidence has shown that m-THPC and verteporfin (VP) are promising sensitizers in photodynamic therapy (PDT). In addition, autophagy can act as a tumor suppressor or a tumor promoter depending on the photosensitizer (PS) and the cancer cell type. However, the role of autophagy in m-THPC- and VP-mediated PDT in in vitro and in vivo models of human colorectal cancer (CRC) has not been reported. In this study, m-THPC-PDT or VP-PDT exhibited significant phototoxicity, inhibited proliferation, and induced the generation of large amounts of reactive oxygen species (ROS) in CRC cells. From immunoblotting, fluorescence image analysis, and transmission electron microscopy, we found extensive autophagic activation induced by ROS in cells. In addition, m-THPC-PDT or VP-PDT treatment significantly induced apoptosis in CRC cells. Interestingly, the inhibition of m-THPC-PDT-induced autophagy by knockdown of ATG5 or ATG7 substantially inhibited the apoptosis of CRC cells. Moreover, m-THPC-PDT treatment inhibited tumorigenesis of subcutaneous HCT116 xenografts. Meanwhile, antioxidant treatment markedly inhibited autophagy and apoptosis induced by PDT in CRC cells by inactivating JNK signaling. In conclusion, inhibition of autophagy can remarkably alleviate PDT-mediated anticancer efficiency in CRC cells via inactivation of the ROS/JNK signaling pathway. Our study provides evidence for the therapeutic application of m-THPC and VP in CRC.

Prognostic and clinical significance of long non-coding RNA SNHG12 expression in various cancers

Recently, increasing studies suggested that lncRNA SNHG12 was aberrantly expressed in kinds of cancers. However, definite prognostic value of SNHG12 remains unclear. We conducted this meta-analysis to evaluate the association between SNHG12 expression level and cancer prognosis. A literature retrieval was conducted by searching kinds of databases. The meta-analysis was performed by using Revman 5.2 and Stata 12.0 software. Besides, The Cancer Genome Atlas dataset was analyzed to validate the results in our meta-analysis via using Gene Expression Profiling Interactive Analysis. The pooled results showed that high SNHG12 expression significantly indicated worse overall survival and recurrence-free survival. Tumor type, sample size, survival analysis method, and cutoff value did not alter SNHG12 prognosis value according to stratified analysis results. Additionally, higher expression of SNHG12 suggested unfavorable clinicopathological outcomes including larger tumor size, lymph node metastasis, distant metastasis, and advanced clinical stage. Online cross-validation in TCGA dataset further indicated that cancer patients with upregulated SNHG12 expression had worse overall survival and disease-free survival. Therefore, elevated SNHG12 expression was associated with poor survival and unfavorable clinical outcomes in various cancers, and therefore might be a potential prognostic biomarker in human cancers.

Abbreviations Akt: protein kinase B; CESC: cervical squamous cell carcinoma and endocervical adenocarcinoma; ceRNA: competitive endogenous RNA; CNKI: China National Knowledge Infrastructure; CI: confidence interval; CCNE1: cyclin E1; COAD: colon adenocarcinoma; DM: distant metastasis; DFS: disease-free survival; EMT: epithelial–mesenchymal transition; FISH: fluorescence in situ hybridization; FIGO: the International Federation of Gynecology and Obstetrics; GEPIA: Gene Expression Profiling Interactive Analysis; HR: hazard ratio; HIFα: hypoxia-inducible factor 1 α; KIRC: kidney renal clear cell carcinoma; KIRP: kidney renal papillary cell carcinoma; LIHC: hepatocellular carcinoma; LNM: lymph node metastasis; mTOR: mechanistic target of rapamycin kinase; MMP-9: matrix metalloproteinase 9; MCL1: myeloid cell leukemia 1; MLK3: mixed-lineage protein kinase 3; N/A: not available; NOS: Newcastle-Ottawa Scale; OR: odd ratio; OS: overall survival; PSA: prostate-specific antigen; PI3K: phosphoinositide 3-kinase; qRT-PCR: quantitative real-time polymerase chain reaction; READ: rectum adenocarcinoma; RFS: recurrence-free survival; SARC: sarcoma; SNHG12: small nucleolar RNA host gene 12; STAT3: signal transducer and activator of transcription 3; SOX4: SRY-box transcription factor 4; SOX5: SRY-box transcription factor 5; STAD: stomach adenocarcinoma; TCGA: The Cancer Genome Atlas; TNM: tumor node metastasis; WWP1: WW domain-containing E3 ubiquitin protein ligase 1; WHO grade: World Health Organization grade; ZEB2: zinc finger E-box-binding homeobox 2

The Pseudogene DUXAP8 Promotes Colorectal Cancer Cell Proliferation, Invasion, and Migration by Inducing Epithelial-Mesenchymal Transition Through Interacting with EZH2 and H3K27me3

Background

Colorectal cancer (CRC) is the third leading cause of cancer death worldwide. The long noncoding RNA (lncRNA) DUXAP8 has been reported to play an important role in CRC. This study investigated the mechanism by which this lncRNA regulates CRC progression.

Methods

The levels of lncRNA DUXAP8 in CRC tissues and cell lines were detected by qRT-PCR. We then knocked down or forced overexpression of DUXAP8, and the resultant effect on cell proliferation was determined by the Edu assay and a cell cycle analysis, and the effect on cell apoptosis was determined by flow cytometry. The cell invasion/migration ability and the epithelial-to-mesenchymal transition (EMT) markers were determined by Transwell/wound healing assays and Western blotting. CHIP and RNA pull-down assays were performed to determine the binding of Zeste gene enhancer 2 (EZH2) and trimethylated histone H3 to Lys27 (H3K27me3) in the E-cadherin promoter regions, or to DUXAP8.

Results

The levels of lncRNA DUXAP8 were significantly increased in CRC tissues and CRC cell lines. Knockdown of lncRNA DUXAP8 inhibited cell proliferation and the EMT process, and increased cell apoptosis, and overexpression of lncRNA DUXAP8 had an opposite effect. Both ChIP and RNA pull-down assays showed that the E-cadherin promoter region was bound by H3K27me3 and EZH2, which restrained E-cadherin expression. However, that binding was suppressed and E-cadherin expression was markedly induced by lncRNA DUXAP8 knockdown. Furthermore, lncRNA DUXAP8 could interact with EZH2 and H3K27me3.

Conclusion

Our data indicated that lncRNA DUXAP8 could induce the progression of CRC by negatively regulating E-cadherin via interaction with EZH2 and H3K27me3. These findings suggest lncRNA DUXAP8 as target for treating CRC.

The relationship between Long Noncoding RNA (lncRNA) Small Nucleolar RNA Host Gene 12 (SNHG12) expression in solid malignant tumors and prognosis of tumor patients: A systematic review and meta-analysis

BACKGROUND

Small nucleolar RNA host gene 12 (SNHG12) has been demonstrated to be a long noncoding RNA (lncRNA) that facilitates the progression of several solid malignant tumors. However, whether the expression level of SNHG12 in solid malignant tumors is associated with patients prognosis have not been investigated.

METHODS

We systematically searched PubMed, EMBASE and Cochrane Library from Jan 1, 1950 to Mar 24, 2020 for randomized controlled trials published in English on SNHG12 expression in solid malignant tumors. We used the Newcastle-Ottawa Scale to assess the quality of articles. The HRs and 95%CI that extracted from Kaplan-Meier curves were used to perform the forest plot using a fixed-effects model. The meta-analysis was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

RESULTS

Thirteen articles containing 821 patients were included in this systematic review and meta-analysis. The result showed that high lncRNA SNHG12 expression is significantly associated with poor overall survival (OS) (HR = 1.94, 95% CI: 1.56-2.41, P < .001) and the studies are lack of statistically significant heterogeneity (P= .878, I = 0.0%). Beggs plot and Eggers test were applied to testify no publication bias existence in these studies. Subgroup analyses were performed and the result showed that TNM stage, lymph node metastasis and tumor type can influence the patients outcome, while there was no significantly correlation between SNHG12 expression and gender.

CONCLUSIONS

The systematical review and meta-analysis synthetically analyzed 13 articles including 821 patients with ten types of solid malignant tumors, concluding that higher lncRNA SNHG12 expression is significantly associated with worse clinical prognosis.

Silencing of Long Non-Coding RNA (lncRNA) Nuclear Paraspeckle Assembly Transcript 1 (NEAT1) Protects PC-12 Cells from LPS-Induced Injury via Targeting miR-29a

Background

Spinal cord injury (SCI) is a debilitating neuropathological condition that significantly affects the quality of life. The present study is basic research examining the underlying mechanisms of NEAT1 and miR-29a in regulating LPS-induced PC-12 cell injury.

Material/Methods

The model of cell injury was induced by the treatment of PC-12 cells with LPS. The expressions of NEAT1, miR-29a, and inflammatory cytokines were measured by real-time quantitative polymerase chain reactions (RT-qPCR). Cell proliferation and apoptosis were evaluated by CCK-8 and flow cytometry, respectively. Finally, the target between miR-29a and NEAT1 as well as miR-29a and BCL2L11 was investigated by luciferase and RNA pull-down assays.

Results

Knockdown of NEAT1 can inhibit inflammatory cytokine expression and PC-12 cell apoptosis and promote PC-12 cell proliferation by targeting miR-29a. However, the variation caused by NEAT1 knockdown can be reversed by the silencing of miR-29a and the overexpression of BCL2L11, which is the direct target gene of miR-29a.

Conclusions

High NEAT1 levels can increase LPS-induced injury in PC-12 cells through the miR-29a/BCL2L11 pathway. lncRNA NEAT1 may, therefore, be a promising target for SCI treatment.

SNHG12/miR-326/E2F1 feedback loop facilitates the progression of oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is a kind of common malignant tumor worldwide. An increasing number of researches have validated that long non-coding RNAs (lncRNAs) are closely associated with the occurrence and development of multiple diseases, including cancers. However, the role of lncRNA SNHG12 in OSCC was largely unknown. In present study, qRT-PCR manifested the upregulation of SNHG12 expression in OSCC tissues and cells. Suppression of SNHG12 inhibited cell proliferation, migration, invasion, and EMT process in OSCC. Additionally, SNHG12 depletion also attenuated OSCC tumor growth in vivo. Thereafter, E2F1 was found to be a transcription factor of SNHG12 to stimulate its expression. More interestingly, SNHG12 deficiency reduced E2F1 expression in turn. MiR-326 was found to be shared between SNHG12 and E2F1. Besides, SNHG12 augmented E2F1 in OSCC through miR-326 sequestration. Finally, rescue assays demonstrated that overexpressed E2F1 restored the inhibitory effect resulted from SNHG12 silence, indicating that SNHG12 promoted the progression of OSCC by E2F1-dependent way. This research unveiled that SNHG12/miR-326/E2F1 feedback loop facilitated OSCC progression, which shed new light on therapeutic methods in OSCC.

Long Noncoding RNA SNHG12 Indicates the Prognosis and Accelerates Tumorigenesis of Diffuse Large B-Cell Lymphoma Through Sponging microR-195

Background

Small nucleolar RNA host gene 12 (SNHG12) expression is associated with multiple cancers, including renal cell carcinoma, prostate cancer, cervical cancer, nasopharyngeal carcinoma, colorectal cancer, and hepatocellular carcinoma. However, SNHG12 biological function is unclear in diffuse large B-cell lymphoma (DLBCL).

Methods

SNHG12 expression and associated clinicopathological characteristics were evaluated in DLBCL tissues. CCK-8 and transwell assay were used to analyze the in vitro role of SNHG12 in DLBCL progression. The xenograft model was used to explore the in vivo role of SNHG12 in DLBCL growth. The physical interaction between SNHG12 and miR-195 was confirmed using bioinformatics analysis and a dual luciferase assay.

Results

SNHG12 expression was upregulated in DLBCL tissues and correlated with patients’ prognosis. SNHG12 downregulation inhibited cell growth, migration, and invasion of DLBCL cells in vitro, while its overexpression promoted these cellular processes. Moreover, SNHG12 knockdown repressed tumorigenesis of DLBCL cells in vivo. Further experiments demonstrated that miR-195 is a target of SNHG12 in DLBCL and that their expression negatively correlates in DLBCL. SNHG12 functioned as a competing endogenous RNA for miR-195 in DLBCL cells and miR-195 upregulation abolished the effects of SNHG12 on of DLBCL progression.

Conclusion

SNHG12 predicts poor clinical outcome and serves as a novel oncogene in DLBCL via miR-195 sponging. We also suggest that SNHG12 can be used as a potential therapeutic candidate for DLBCL patients.

An Emerging Class of Long Non-coding RNA With Oncogenic Role Arises From the snoRNA Host Genes

The small nucleolar RNA host genes (SNHGs) are a group of long non-coding RNAs, which are reported in many studies as being overexpressed in various cancers. With very few exceptions, the SNHGs (SNHG1, SNHG3, SNHG5, SNHG6, SNHG7, SNHG12, SNHG15, SNHG16, SNHG20) are recognized as inducing increased proliferation, cell cycle progression, invasion, and metastasis of cancer cells, which makes this class of transcripts a viable biomarker for cancer development and aggressiveness. Through our literature research, we also found that silencing of SNHGs through small interfering RNAs or short hairpin RNAs is very effective in both in vitro and in vivo experiments by lowering the aggressiveness of solid cancers. The knockdown of SNHG as a new cancer therapeutic option should be investigated more in the future.

Knockdown of lncRNA SNHG12 suppresses cell proliferation, migration and invasion in breast cancer by sponging miR-451a

BACKGROUND

Breast cancer (BC) is a common cancer with high incidence in women worldwide. Although there are some studies focusing on the pathogenesis of BC, the regulatory mechanism needs to be further investigated. The function of lncRNA and miRNA has been demonstrated to participate in cell progression of BC. However, the function of SNHG12 has not been clearly elucidated.

METHODS

We detected the expression of SNHG12 and miR-451a using quantitative real-time PCR (qRT-PCR). The protein expression of AKT, p-AKT, mTOR and p-mTOR were measured using western blot. The relationship between SNHG12 and miR-451a was confirmed by luciferase reporter assay. Cell proliferation was measured using MTT assay. Transwell assay was used to detect cell migration and invasion. Xenograft transplantation was used to detect the function of SNHG12 in vivo.

RESULTS

In this study, we found that SNHG12 was significantly increased in BC tissues and cells. Knockdown of SNHG12 inhibited BC cell proliferation, invasion, and migration in vitro as well as suppressed tumor growth in vivo. In addition, miR-451a expression was obviously down-regulated in BC tissues and had negative correlation with SNHG12. Luciferase reporter assay determined that miR-451a was a target miRNA of SNHG12. Notably, SNHG12 knockdown decreased cell proliferation, migration, invasion, and AKT/mTOR pathway activation which could be reversed by down-regulation of miR-451a.

CONCLUSION

Knockdown of SNHG12 inhibited cell proliferation, invasion, and migration by regulating miR-451a through suppression of AKT/mTOR pathway in BC.

Long noncoding RNA SNHG12 suppresses esophageal squamous cell carcinoma progression through competing endogenous RNA networks

PURPOSE

Esophageal squamous cell cancer (ESCC) has high rates of recurrence and mortality. Small nucleolar RNA host gene 12 (SNHG12) is known to promote the progression of several cancers. Therefore, we aimed to investigate the expression and role of SNHG12 in ESCC.

METHODS

The expression and clinical value of SNHG12 in esophageal cancer were explored using data from The Cancer Genome Atlas (TCGA) and the online server GEPIA. Real-time quantitative polymerase chain reaction (qRT-PCR) was used to verify the expression levels of SNHG12 in ESCC tissues and cell lines. Furthermore, loss-of-function assays were performed to examine the effect of SNHG12 on ESCC cells in vitro and in vivo. The potential competing endogenous RNA networks of SNHG12 in ESCC were explored.

RESULTS

SNHG12 was downregulated in human ESCA tissues compared to control tissues. The expression of SNHG12 was strongly associated with T stage, N stage, and TNM stage. Low SNHG12 expression in esophageal tumor tissues was significantly correlated with poor prognosis. Furthermore, knockdown of SNHG12 not only promoted proliferation, colony formation, migration, and invasion and inhibited apoptosis in ESCC cells in vitro, but also increased tumor growth in vivo. Additionally, this proves that the SNHG12/miRNA-195-5p/BCL9 network might be involved in ESCC.

CONCLUSION

This is the first study to reveal that SNHG12 is downregulated in ESCC tissues and could be used as a prognostic tool. SNHG12 suppressed tumor progression in ESCC cells, serving as a potential biomarker. The SNHG12/miRNA-195-5p/BCL9 network is proposed to be the mechanism leading to ESCC progression.

Long noncoding RNA SNHG12 modulated by human papillomavirus 16 E6/E7 promotes cervical cancer progression via ERK/Slug pathway

Recently, long noncoding RNA SNHG12 has been reported to be dysregulated in various types of cancer. This study investigated its biological function and the underlying molecular mechanism in cervical squamous cell carcinoma (CSCC). We found that SNHG12 was significantly overexpressed in CSCC tissues. Further evidence showed that human papillomavirus (HPV) type 16 E6 and E7 might regulate the expression level of SNHG12 by modulating transcription factor c-Myc. Functional experiments suggested that SNHG12 knockdown dramatically repressed CSCC cells proliferation, migration, and invasion while induced apoptosis in vitro as well as suppressed tumor growth in vivo. In addition, SNHG12 could facilitate epithelial-mesenchymal transition through ERK/Slug/E-cadherin pathway at least in part. Our findings highlight SNHG12 functions as an oncogenic long noncoding RNA in malignant phenotype and tumorigenesis of CSCC, which implicate it may be a potential target for CSCC treatment.

RNA-based therapeutics for colorectal cancer: Updates and future directions

Colorectal cancer (CRC) is one of the most common causes of cancer death worldwide. While standard chemotherapy and new targeted therapy have been improved recently, problems such as multidrug resistance (MDR) and severe side effects remain unresolved. RNAs are essential to all biological processes including cell proliferation and differentiation, cell cycle, apoptosis, activation of tumor suppressor genes, suppression of oncogenes. Therefore, there are various potential approaches to address genetic disease like CRC at the RNA level. In contrast to conventional treatments, RNA-based therapeutics such as RNA interference, antisense oligonucleotides, RNA aptamer, ribozymes, have the advantages of high specificity, high potency and low toxicity. It has gained more and more attention due to the flexibility in modulating a wide range of targets. Here, we highlight recent advances and clinical studies involving RNA-based therapeutics and CRC. We also discuss their advantages and limitations that remain to be overcome for the treatment of human CRC.

LncRNA SNHG4 promotes the proliferation, migration, invasiveness, and epithelial–mesenchymal transition of lung cancer cells by regulating miR-98-5p

Long noncoding RNA small nucleolar RNA host gene 4 (SNHG4) is usually up-regulated in cancer and regulates the malignant behavior of cancer cells. However, its role in lung cancer remains elusive. In this study, we silenced the expression of SNHG4 in NCI-H1437 and SK-MES-1, two representative non-small-cell lung cancer cell lines, by transfecting them with siRNA (small interfering RNA) that specifically targets SNHG4. We observed significantly inhibited cell proliferation in vitro and reduced tumor growth in vivo after SNHG4 silencing. SNHG4 knockdown also led to cell cycle arrest at the G1 phase, accompanied with down-regulation of cyclin-dependent kinases CDK4 and CDK6. The migration and invasiveness of these two cell lines were remarkably inhibited after SNHG4 silencing. Moreover, our study revealed that the epithelial–mesenchymal transition (EMT) of lung cancer cells was suppressed by SNHG4 silencing, as evidenced by up-regulated E-cadherin and down-regulated SALL4, Twist, and vimentin. In addition, we found that SNHG4 silencing induced up-regulation of miR-98-5p. MiR-98-5p inhibition abrogated the effect of SNHG4 silencing on proliferation and invasion of lung cancer cells. In conclusion, our findings demonstrate that SNHG4 is required by lung cancer cells to maintain malignant phenotype. SNHG4 probably exerts its pro-survival and pro-metastatic effects by sponging anti-tumor miR-98-5p.

Long non-coding small nucleolar RNA host genes in digestive cancers

Although long noncoding RNAs (lncRNAs) do not have protein coding capacities, they are involved in the pathogenesis of many types of cancers, including hepatocellular carcinoma, cervical cancer, and gastric cancer. Notably, the roles of lncRNAs are vital in nearly every aspect of tumor biology. Long non-coding small nucleolar RNA host genes (lnc-SNHGs) are abnormally expressed in multiple cancers, including urologic neoplasms, respiratory tumors, and digestive cancers, and play vital roles in these cancers. These host genes could participate in tumorigenesis by regulating proliferation, migration, invasion and apoptosis of tumor cells. This review focuses on the overview of the roles that lnc-SNHGs play in the formation and progression of digestive cancers.

Genome-wide discovery and characterization of long noncoding RNAs in patients with multiple myeloma

Background

Long noncoding RNAs (lncRNAs) are involved in a wide range of biological processes in tumorigenesis. However, the role of lncRNA expression in the biology, prognosis, and molecular classification of human multiple myeloma (MM) remains unclear, especially the biological functions of the vast majority of lncRNAs. Recently, lncRNAs have been identified in neoplastic hematologic disorders. Evidence has accumulated on the molecular mechanisms of action of lncRNAs, providing insight into their functional roles in tumorigenesis. This study aimed to characterize potential lncRNAs in patients with MM.

Methods

In this study, the whole-transcriptome strand-specific RNA sequencing of samples from three newly diagnosed patients with MM was performed. The whole transcriptome, including lncRNAs, microRNAs, and mRNAs, was analyzed. Using these data, MM lncRNAs were systematically analyzed, and the lncRNAs involved in the occurrence of MM were identified.

Results

The results revealed that MM lncRNAs had distinctive characteristics different from those of other malignant tumors. Further, the functions of a set of lncRNAs preferentially expressed in MM were verified, and several lncRNAs were identified as competing endogenous RNAs. More importantly, the aberrant expression of certain lncRNAs, including maternally expressed gene3, colon cancer–associated transcript1, and coiled-coil domain-containing 26, as well as some novel lncRNAs involved in the occurrence of MM was established. Further, lncRNAs were related to some microRNAs, regulated each other, and participated in MM development.

Conclusions

Genome-wide screening and functional analysis enabled the identification of a set of lncRNAs involved in the occurrence of MM. The interaction exists among microRNAs and lncRNAs.

SNHG12: An LncRNA as a Potential Therapeutic Target and Biomarker for Human Cancer

Limitations in current diagnostic procedures warrant identification of new methodologies to improve diagnoses of cancer patients. In this context, long non-coding RNAs (lncRNAs) have emerged as stable biomarkers which are expressed abundantly in tumors. Importantly, these can be detected at all stages of tumor development, and thus may provide potential biomarkers and/or therapeutic targets. Recently, we suggested that aberrant levels of lncRNAs can be used to determine the invasive and metastatic potential of tumor cells. Further, direct correlations of lncRNAs with cancer-derived inflammation, metastasis, epithelial-to-mesenchymal transition, and other hallmarks of cancer indicate their potential as biomarkers and targets for cancer. Thus, in this review we have discussed the importance of small nucleolar RNA host gene 12 (SNHG12), a lncRNA, as a potential biomarker for a variety of cancers. A meta-analysis of a large cohort of cancer patients revealed that SNHG12 may also serve as a potential target for cancer-directed interventions due to its involvement in unfolded protein responses, which many tumor cells exploit to both evade immune-mediated attack and enhance the polarization of effector immune cells (e.g., macrophages and T cells). Thus, we propose that SNHG12 may serve as both a biomarker and a druggable therapeutic target with promising clinical potential.

Diagnostic and prognostic potential of tissue and circulating long non-coding RNAs in colorectal tumors

Long non-coding RNAs (lncRNAs) are members of the non-protein coding RNA family longer than 200 nucleotides. They participate in the regulation of gene and protein expression influencing apoptosis, cell proliferation and immune responses, thereby playing a critical role in the development and progression of various cancers, including colorectal cancer (CRC). As CRC is one of the most frequently diagnosed malignancies worldwide with high mortality, its screening and early detection are crucial, so the identification of disease-specific biomarkers is necessary. LncRNAs are promising candidates as they are involved in carcinogenesis, and certain lncRNAs (e.g., CCAT1, CRNDE, CRCAL1-4) show altered expression in adenomas, making them potential early diagnostic markers. In addition to being useful as tissue-specific markers, analysis of circulating lncRNAs (e.g., CCAT1, CCAT2, BLACAT1, CRNDE, NEAT1, UCA1) in peripheral blood offers the possibility to establish minimally invasive, liquid biopsy-based diagnostic tests. This review article aims to describe the origin, structure, and functions of lncRNAs and to discuss their contribution to CRC development. Moreover, our purpose is to summarise lncRNAs showing altered expression levels during tumor formation in both colon tissue and plasma/serum samples and to demonstrate their clinical implications as diagnostic or prognostic biomarkers for CRC.

Knockdown of lncRNA CCEPR suppresses colorectal cancer progression

Long non-coding RNAs (lncRNAs) serve important roles in colorectal cancer. The aim of the present study was to investigate the expression and role of cervical carcinoma expressed PCNA regulatory (CCEPR) lncRNA in colorectal cancer progression. The results demonstrated that CCEPR expression was significantly higher in colorectal cancer tissues when compared with paired adjacent normal tissues. In addition, CCEPR expression was significantly higher in patients with advanced colorectal cancer (stage III/IV) than those with early-stage colorectal cancer (stage I/II). High CCEPR expression was significantly associated with poor differentiation, advanced clinical stage, positive lymph node metastasis and distant metastasis. Of particular note, patients with colorectal cancer exhibiting high CCEPR expression levels had shorter survival rates when compared with patients with low CCEPR expression. In vitro experiments demonstrated that the expression of CCEPR was increased in colorectal cancer cell lines when compared with a normal colon cell line. Knockdown of CCEPR significantly inhibited colorectal cancer cell proliferation, colony formation and cell cycle progression, as well as cell migration and invasion. Finally, silencing of CCEPR downregulated matrix metalloproteinase (MMP)-2 and MMP-9 expression and suppressed epithelial-mesenchymal transition in colorectal cancer cells. In conclusion, the results of the present study suggest that CCEPR may exert an oncogenic role in colorectal cancer, and CCEPR may be a promising molecular target for colorectal cancer treatment.