Helicobacter pylori infection, H19 and LINC00152 expression in serum and risk of gastric cancer in a Chinese population

A prominent role of LncRNA H19 in H. pylori CagA induced DNA damage response and cell malignancy

Helicobacter pylori (H. pylori), together with its CagA, has been implicated in causing DNA damage, cell cycle arrest, apoptosis, and the development of gastric cancer. Although lncRNA H19 is abundantly expressed in gastric cancer and functions as a pro-oncogene, it remains unclear whether lncRNA H19 contributes to the oncogenic process of H. pylori CagA. This study investigates the role of H19 in the DNA damage response and malignancy induced by H. pylori. It was observed that cells infected with CagA+ H. pylori strain (GZ7/cagA) showed significantly higher H19 expression, resulting in increased γH2A.X and p-ATM expression and decreased p53 and Rad51 expression. Faster cell migration and invasion was also observed, which was reversed by H19 knockdown in H. pylori. YWHAZ was identified as an H19 target protein, and its expression was increased in H19 knockdown cells. GZ7/cagA infection responded to the increased YWHAZ expression induced by H19 knockdown. In addition, H19 knockdown stimulated cells to enter the G2-phase and attenuated the effect of GZ7/cagA infection on the cellular S-phase barrier. The results suggest that H. pylori CagA can upregulate H19 expression, participate in the DNA damage response and promote cell migration and invasion, and possibly affect cell cycle arrest via regulation of YWHAZ.

The prognostic, diagnostic, and therapeutic impact of Long noncoding RNAs in gastric cancer

Gastric cancer (GC), ranking as the third deadliest cancer globally, faces challenges of late diagnosis and limited treatment efficacy. Long non-coding RNAs (lncRNAs) emerge as valuable treasured targets for cancer prognosis, diagnosis, and therapy, given their high specificity, convenient non-invasive detection in body fluids, and crucial roles in diverse physiological and pathological processes. Research indicates the significant involvement of lncRNAs in various aspects of GC pathogenesis, including initiation, metastasis, and recurrence, underscoring their potential as novel diagnostic and prognostic biomarkers, as well as therapeutic targets for GC. Despite existing challenges in the clinical application of lncRNAs in GC, the evolving landscape of lncRNA molecular biology holds promise for advancing the survival and treatment outcomes of gastric cancer patients. This review provides insights into recent studies on lncRNAs in gastric cancer, elucidating their molecular mechanisms and exploring the potential clinical applications in GC.

Role of lncRNAs in Helicobacter pylori and Epstein-Barr virus associated gastric cancers

Helicobacter pylori infection is a risk factor for the development of gastric cancer (GC), and the role of co-infection with viruses, such as Epstein-Barr virus, in carcinogenesis cannot be ignored. Furthermore, it is now known that genetic factors such as long non-coding RNAs (lncRNAs) are involved in many diseases, including GC. On the other side, they can also be used as therapeutic goals. Modified lncRNAs can cause aberrant expression of genes encoding proximal proteins, which are essential for the development of carcinoma. In this review, we present the most recent studies on lncRNAs in GC, concentrating on their roles in H. pylori and EBV infections, and discuss some of the molecular mechanisms of these GC-related pathogens. There was also a discussion of the research gaps and future perspectives.

Recent progress in biomarker-based diagnostics of Helicobacter pylori, gastric cancer-causing bacteria

The progression of any disease and its outcomes depend on the complicated interaction between pathogens, host and environmental factors. Thus, complete knowledge of bacterial toxins involved in pathogenesis is necessary to develop diagnostic methods and alternative therapies, including vaccines. This review summarizes recently employed biomarkers to diagnose the presence of Helicobacter pylori bacteria. The authors review distinct types of disease-associated biomarkers such as urease, DNA, miRNA, aptamers and bacteriophages that can be utilized as targets to detect Helicobacter pylori and, moreover, gastric cancer in its early stage. A detailed explanation is also given in the context of the recent utilization of these biomarkers in the development of a highly specific and sensitive biosensing platform.

Gastric cancer-associated long non-coding RNA profiling and noninvasive biomarker screening based on a high-risk population cohort

BACKGROUND

Effective noninvasive biomarkers of gastric cancer (GC) are critical for early detection and improvement of prognosis. We performed genome-wide long non-coding RNA (lncRNA) microarray analysis to identify and validate novel GC biomarkers depending on a high-risk population cohort.

METHODS

LncRNA profiles were described using the Human LncRNA Microarray between GC and control plasma samples. The differential candidate lncRNAs were validated in two stages by quantitative reverse transcription polymerase chain reaction (qRT-PCR). We further evaluated the joint effect between the GC-associated lncRNA and Helicobacter pylori (H. pylori) infection on the risk of cardia and non-cardia GC, respectively.

RESULTS

Different lncRNA expression profiles were identified between GC and control plasma with a total of 1206 differential lncRNAs including 470 upregulated and 736 downregulated in GC compared with the control group. The eight significantly upregulated lncRNAs (RP11-521D12.1, AC011995.3, RP11-5P4.3, RP11-244 K5.6, RP11-422 J15.1, CTD-2306 M5.1, CTC-428G20.2, and AC009133.20) in GC cases both in the present study and a similar microarray screening study by our collaborative team were selected for a two-stage validation. After the large sample size validation, the subjects with higher expression of RP11-244 K5.6 showed a significantly increased risk of GC with an adjusted odds ratio (OR) as 2.68 and 95% confidence interval (CI) as 1.15-6.24. Joint effects between RP11-244 K5.6 expression and H. pylori infection on the risk of GC were evaluated with no statistical significance.

CONCLUSIONS

Our study found different lncRNA expression profiles between GC and control plasma and preliminarily identified RP11-244 K5.6 as a potential noninvasive biomarker for GC screening.

A review on the role of LINC00152 in different disorders

LINC00152 is an important lncRNA in human disorders. It is mainly regarded as a tumor-promoting lncRNA. Mechanistically, LINC00152 serves as a molecular sponge for miR-143a-3p, miR-125a-5p, miR-139, miR-215, miR-193a/b-3p, miR-16-5p, miR-206, miR-195, miR-138, miR-185-5p, miR-103, miR-612, miR-150, miR-107, miR-205-5p and miR-153-3p. In addition, it can regulate activity of mTOR, EGFR/PI3K/AKT, ERK/MAPK, Wnt/β-Catenin, EGFR, NF-κB, HIF-1 and PTEN. In this review, we provide a concise but comprehensive explanation about the role of LINC00152 in tumor development and progression as well as its role in the pathology of non-malignant conditions with the aim of facilitating the clinical implementation of this lncRNA as a diagnostic or prognostic tumor marker and therapeutic target.

Epithelial-mesenchymal transition-related long noncoding RNAs in gastric carcinoma

As an evolutionarily phenotypic conversion program, the epithelial-mesenchymal transition (EMT) has been implicated in tumour deterioration and has facilitated the metastatic ability of cancer cells via enhancing migration and invasion. Gastric cancer (GC) remains a frequently diagnosed non-skin malignancy globally. Most GC-associated mortality can be attributed to metastasis. Recent studies have shown that EMT-related long non-coding RNAs (lncRNAs) play a critical role in GC progression and GC cell motility. In addition, lncRNAs are associated with EMT-related transcription factors and signalling pathways. In the present review, we comprehensively described the EMT-inducing lncRNA molecular mechanisms and functional perspectives of EMT-inducing lncRNAs in GC progression. Taken together, the statements of this review provided a clinical implementation in identifying lncRNAs as potential therapeutic targets for advanced GC.

Comprehensive Mapping of the Cell Response to Borrelia bavariensis in the Brain Microvascular Endothelial Cells in vitro Using RNA-Seq

Borrelia bavariensis can invade the central nervous system (CNS) by crossing the blood-brain barrier (BBB). It is predicted that B. bavariensis evokes numerous signaling cascades in the human brain microvascular endothelial cells (hBMECs) and exploits them to traverse across the BBB. The complete picture of signaling events in hBMECs induced by B. bavariensis remains uncovered. Using RNA sequencing, we mapped 11,398 genes and identified 295 differentially expressed genes (DEGs, 251 upregulated genes and 44 downregulated genes) in B. bavariensis challenged hBMECs. The results obtained from RNA-seq were validated with qPCR. Gene ontology analysis revealed the participation of DEGs in a number of biological processes like cell communication, organization of the extracellular matrix, vesicle-mediated transport, cell response triggered by pattern recognition receptors, antigen processing via MHC class I, cellular stress, metabolism, signal transduction, etc. The expression of several non-protein coding genes was also evoked. In this manuscript, we discuss in detail the correlation between several signaling cascades elicited and the translocation of BBB by B. bavariensis. The data revealed here may contribute to a better understanding of the mechanisms employed by B. bavariensis to cross the BBB.

Moderate Prognostic Value of lncRNA FOXD2-AS1 in Gastric Cancer with Helicobacter pylori Infection

PURPOSE

Gastric cancer (GC) is one of the most frequent tumors worldwide and identification of a sensitive and specific prognostic biomarker is of great importance. Long non-coding RNAs (lncRNAs) play crucial roles in tumorigenesis of various malignancies. In the present study, we investigated lncRNA FOXD2-AS1 expression in gastric tumors and assessed its potential as a prognostic biomarker.

METHODS

A total of 95 tumor and corresponding adjacent non-tumor tissue specimens were collected from patients with GC from Imam Reza hospital, Tabriz, Iran. Total RNA was isolated and FOXD2-AS1 expression was measured using quantitative reverse transcriptase (qRT)-PCR.

RESULTS

FOXD2-AS1 was significantly upregulated in tumor samples as compared to non-tumor tissues (P < 0.0001). In addition, higher expression of FOXD2-AS1 was significantly associated with lymph node metastasis and Helicobacter pylori infection. The receiver operating characteristic (ROC) curve analysis revealed that FOXD2-AS1 might be served as a potential prognostic biomarker for GC.

CONCLUSION

FOXD2-AS1 is upregulated in gastric tumors and can be used as a valuable biomarker in the prognosis of patients with GC.

LncRNA H19: A novel oncogene in multiple cancers

Long non-coding RNAs (lncRNAs) are a series of non-coding RNAs that lack open reading frameworks. Accumulating evidence suggests important roles for lncRNAs in various diseases, including cancers. Recently, lncRNA H19 (H19) became a research focus due to its ectopic expression in human malignant tumors, where it functioned as an oncogene. Subsequently, H19 was confirmed to be involved in tumorigenesis and malignant progression in many tumors and had been implicated in promoting cell growth, invasion, migration, epithelial-mesenchymal transition, metastasis, and apoptosis. H19 also sequesters some microRNAs, facilitating a multilayer molecular regulatory mechanism. In this review, we summarize the abnormal overexpression of H19 in human cancers, which suggests wide prospects for further research into the diagnosis and treatment of cancers.

Helicobacter pylori Infection-Related Long Non-Coding RNA Signatures Predict the Prognostic Status for Gastric Cancer Patients

Background

Helicobacter pylori (H. pylori) is a type I biological carcinogen, which may cause about 75% of the total incidence of gastric cancer worldwide. H. pylori infection can induce and activate the cancer-promoting signaling pathway and affect the occurrence and outcome of gastric cancer through controlling the regulatory functions of long non-coding RNAs (lncRNAs). However, we have no understanding of the prognostic worth of lncRNAs for gastric cancer patients infected with H. pylori.

Method

We screened differentially expressed lncRNAs using DESeq2 method among TCGA database. And we built the H. pylori infection-related lncRNAs regulatory patterns. Then, we constructed H. pylori infection-based lncRNAs prognostic signatures for gastric cancer patients together with H. pylori infection, via uni-variable and multi-variable COX regression analyses. Based on receiver operator characteristic curve (ROC) analysis, we evaluated the prediction effectiveness for this model.

Results

We identified 115 H. pylori infection-related genes were differentially expressed among H. pylori-infected gastric cancer tissues versus gastric cancer tissues. Functional enrichment analysis implies that H. pylori infection might interfere with the immune-related pathways among gastric cancer tissues. Then, we built H. pylori infection-related dys-regulated lncRNA regulatory networks. We also identified 13 differentially expressed lncRNAs were associated with prognosis for gastric cancer patients together with H. pylori infection. Kaplan-Meier analysis demonstrated that the lncRNA signatures were correlated with the poor prognosis. What is more, the AUC of the lncRNA signatures was 0.712. Also, this prognostic prediction model was superior to the traditional clinical characters.

Conclusion

We successfully constructed a H. pylori-related lncRNA risk signature and nomogram associated with H. pylori-infected gastric cancer patients prognosis, and the signature and nomogram can predict the prognosis of these patients.

Dysregulation of lncRNA in Helicobacter pylori-Infected Gastric Cancer Cells

Helicobacter pylori (H. pylori) infection is the most common cause of gastric cancer (GC). This microorganism is genetically diverse; GC is caused by several genetic deregulations in addition to environmental factors and bacterial virulence factors. lncRNAs (long noncoding RNAs) are significant biological macromolecules in GC, have specific functions in diseases, and could be therapeutic targets. Altered lncRNAs can lead to the abnormal expression of adjacent protein-coding genes, which may be important in cancer development. Their mechanisms have not been well understood, so we are going to investigate the risk of GC in a population with both high lncRNA and H. pylori infection.

Association of gut microbiomes with lung and esophageal cancer: a pilot study

Gut microbiota, especially human pathogens, has been shown to be involved in the occurrence and development of cancer. Esophageal squamous cell carcinoma and lung cancer are two malignant cancers, and their relationship with gut microbiota is still unclear. Virulence factor database (VFDB) is an integrated and comprehensive online resource for curating information about human pathogens. Here, based on VFDB database, we analyzed the differences of bacteria at genus level in the gut of patients with esophageal squamous cell carcinoma, lung cancer, and healthy controls. We proposed the possible cancer-associated bacteria in gut and put forward their possible effects. Apart from this, principal coordinate analysis (PCoA) and analysis of similarities (ANSOIM) suggested that some bacteria in the gut can be used as potential biomarkers to screen esophageal squamous cell carcinoma and lung cancer, and their effectiveness was preliminary verified. The relative abundance of Klebsiella and Streptococcus can be used to distinguish patients with esophageal squamous cell carcinoma and lung cancer from healthy controls. The absolute abundance of Klebsiella can further distinguish patients with esophageal squamous cell carcinoma from patients with lung cancer. In particular, the relative abundance of Fusobacterium can directly distinguish between patients with esophageal squamous cell carcinoma and healthy controls. Additionally, the absolute abundance of Haemophilus can distinguish lung cancer from healthy controls. Our study provided a new way based on VFDB database to explore the relationship between gut microbiota and cancer, and initially proposed a feasible cancer screening method.

Function of Non-coding RNA in Helicobacter pylori-Infected Gastric Cancer

Gastric cancer is a common malignant tumor of the digestive system. Its occurrence and development are the result of a combination of genetic, environmental, and microbial factors. Helicobacter pylori infection is a chronic infection that is closely related to the occurrence of gastric tumorigenesis. Non-coding RNA has been demonstrated to play a very important role in the organism, exerting a prominent role in the carcinogenesis, proliferation, apoptosis, invasion, metastasis, and chemoresistance of tumor progression. H. pylori infection affects the expression of non-coding RNA at multiple levels such as genetic polymorphisms and signaling pathways, thereby promoting or inhibiting tumor progression or chemoresistance. This paper mainly introduces the relationship between H. pylori-infected gastric cancer and non-coding RNA, providing a new perspective for gastric cancer treatment.

Circulating long noncoding RNAs as potential biomarkers for stomach cancer: a systematic review and meta-analysis

Background

Recent researches have suggested that long noncoding RNA (lncRNA) is involved in the tumorigenesis and development of stomach cancer (SC). This meta-analysis aimed to identify the diagnostic performance of circulating lncRNAs in SC.

Methods

All relevant studies were systematically searched through PubMed, Web of Science, Cochrane Library, and EMBASE databases. The diagnostic values of lncRNAs were mainly assessed by pooled sensitivity, specificity, and summary receiver operating characteristic area under the curve (SROC AUC). Meta-DiSc 1.4, Review Manager 5.3, and STATA 12.0 were used for statistical analysis. The protocol for this systematic review was registered on INPLASY (INPLASY202120079) and is available in full on the inplasy.com (10.37766/inplasy2021.2.0079).

Results

A total of 42 eligible studies were included in this meta-analysis. The pooled sensitivity, specificity, and SROC AUC were 0.78 (95%CI 0.75–0.81), 0.75 (95%CI 0.71–0.78), and 0.83 (95%CI 0.80–0.86), respectively, suggesting that the lncRNAs test had a high accuracy for the diagnosis of SC. Obvious heterogeneity might come from the type of lncRNA through subgroup and meta-regression analysis. Fagan diagram shows the clinical value of lncRNAs test in SC.

Conclusions

Abnormal expression of circulating lncRNAs exhibits a high efficacy for diagnosing SC, which is promising in clinical application.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12957-021-02194-6.

LINC00152 mediates CD8+ T-cell infiltration in gastric cancer through binding to EZH2 and regulating the CXCL9, 10/CXCR3 axis

This study aimed to annotate the role of long intergenic non-coding RNA 152 (LINC00152) in CD8⁺ T cells mediated immune responses in gastric cancer (GC) and the underlying mechanism. LINC00152 expression levels were detected through RT-PCR. For tumor engraftment, HGC-27 cells that received LINC00152 shRNA, LINC00152 overexpression vectors, enhancer of zeste homolog 2 (EZH2) shRNA or combination transfection were injected into mice. Chromatin immunoprecipitation (ChIP) assay was used to explore the interaction between LINC00152, Cys-X-cys ligand 9 (CXCL9) and Cys-X-cys ligand 10 (CXCL10). Flow cytometry was adopted to measure the CD8⁺ T-cell infiltration in tumor issue. In this study, we found increased LINC00152 expression levels are positively associated with the poor prognosis of GC patients and negatively associated with the CD8 levels. ChIP assay verified that LINC00152 recruits EZH2 to the promoters of CXCL9 and CXCL10, thus the silencing of LINC00152 promoted the production of CXCL9 and CXCL10. Knockdown of LINC00152 suppressed tumor cells growth in vivo and in vitro, increased tumor-infiltrating CD8⁺ T cells numbers and promoted the expression of CXCL9, CXCL10 and C-X-C Motif Chemokine Receptor 3 (CXCR3) in xenograft tumors. While CD8⁺ T cell depletion reversed the tumor suppression effect of LINC00152 silence. Besides, the silencing of EZH2 partly inhibited the promotion effect LINC00152 on tumor growth. Our study indicated that LINC00152 inhibition suppressed the tumor progress may through promoting CD8⁺ T-cell infiltration.

Role of LINC00152 in non-small cell lung cancer

Non-small cell lung cancer (NSCLC) accounts for about 85% of all lung cancer cases. The pathogenesis of NSCLC involves complex gene networks that include different types of non-coding RNAs, such as long non-coding RNAs (lncRNAs). The role of lncRNAs in NSCLC is gaining an increasing interest as their function is being explored in various human cancers. Recently, a new oncogenic lncRNA, LINC00152 (cytoskeleton regulator RNA (CYTOR)), has been identified in different tumor types. In NSCLC, the high expression of LINC00152 in tumor tissue and peripheral blood samples has been shown to be associated with worse prognoses of NSCLC patients. Overexpression of LINC00152 has been confirmed to promote the proliferation, invasion, and migration of NSCLC cells in vitro, as well as increase tumor growth in vivo. This review discusses the role of LINC00152 in NSCLC.

lncRNA HOTAIR knockdown suppresses gastric cancer cell biological activities

The aim of this study was to characterize the involvement of long noncoding RNA HOTAIR in gastric cancer development. Measurement of HOTAIR and miRNA-206 expression by in situ hybridization (ISH) and analyzed for the correlation between HOTAIR and miRNA-206 in gastric cancer tissues. To evaluate the effects of HOTAIR in gastric cancer, MTT assay, flow cytometry, transwell, and wound healing assays were applied. To explain the mechanism behind HOTAIR's involvement, the expression of proteins related to it was also measured by Western blotting. Finally, correlations among related factors were determined by a luciferase target experiment. HOTAIR expression significantly increased, and miRNA-206 expression significantly decreased in cancer tissues (p < .01 and p < .001, respectively); HOTAIR knockdown suppressed cell viability, increased cell apoptosis by maintaining cells in the G1 phase, and inhibited cell invasion and migration by regulating miRNA-206 expression (p < .01 or p < .001). Meanwhile, with HOTAIR knockdown, CCND1 and CCND2 protein expressions were significantly suppressed, whereas miRNA-206 expression increased (p < .01 or p < .001). HOTAIR was shown to target miRNA-206 and miRNA-206 targeted CCND1 and CCND2. HOTAIR knockdown had antitumor effects by suppressing CCND1 and CCND2 expression by stimulating miRNA-206 in gastric cancer in vitro study.

LINC00152 Promotes Tumor Progression and Predicts Poor Prognosis by Stabilizing BCL6 From Degradation in the Epithelial Ovarian Cancer

Long non-coding RNA 00152 (LINC00152) is tumorigenic in multiple somatic malignancies. However, its prognostic significance and molecular mechanisms in the epithelial ovarian cancer (EOC) remain elusive. Here our study reveals that dysregulation of LINC00152 is a predictor of poor prognosis in patients with EOC and facilitates ovarian tumor growth and metastasis both in vitro and in vivo; the expression of LINC00152 positively correlates with the protein levels of BCL6 in EOC tissues and ovarian tumor cells; LINC00152 binds to Ser333 and Ser343 of BCL6 protein and stabilizes BCL6 from poly-ubiquitination thus facilitating the oncogenic functions in EOC. Moreover, overexpression of the mutant BCL6^S333A/S343A fails to rescue the reduced proliferation and invasion caused by the knockdown of endogenous BCL6 in LINC00152-overexpressing cells. Our study might not only offer clues to the network of lncRNA-protein interactions but also provide potential therapeutic targets for the tumor pharmacology.

A Circulating Long Noncoding RNA Panel Serves as a Diagnostic Marker for Hepatocellular Carcinoma

Background

Circulating long noncoding RNAs (lncRNAs) have been demonstrated to serve as diagnostic biomarkers for various cancers. We aimed to elucidate the diagnostic efficacy of eight serum lncRNAs HULC, MALAT1, Linc00152, PTENP1, PTTG3P, SPRY4-IT1, UBE2CP3, and UCA1 and their combinations for the diagnosis of hepatocellular carcinoma (HCC).

Methods

A total of 129 patients with HCC, 49 patients with liver cirrhosis, 27 patients with chronic hepatitis B, and 93 healthy controls were enrolled in this study. The levels of serum lncRNAs were assessed by quantitative real-time polymerase chain reaction. The correlations between serum lncRNAs and clinicopathological characteristics were further analyzed. The receiver operating characteristic (ROC) curve and area under curve (AUC) were utilized to estimate the diagnostic capacity of serum lncRNAs and their combination with AFP for HCC. A logistic regression model was performed to establish a multiple-lncRNA panel.

Results

The levels of serum HULC, MALAT1, Linc00152, PTTG3P, SPRY4-IT1, UBE2CP3, and UCA1 were significantly higher in HCC patients than in patients with benign liver diseases and healthy controls, whereas serum PTENP1 was significantly decreased in HCC patients compared with healthy participants. Positive correlations between serum Linc00152 and GGT, serum PTTG3P and GGT, and serum SPRY4-IT1 and ALT were noted in HCC patients. ROC analysis revealed that all these lncRNAs had a significantly predictive value for HCC except for PTENP1. The best performance of single lncRNA was obtained by Linc00152 with an AUC of 0.877. When combined with AFP, the combination of Linc00152 and AFP gained the highest accuracy, yielding an AUC of 0.906. Through logistic regression analysis, the panel consisting of serum linc00152, UCA1, and AFP provided the greatest predictive ability, obtaining an AUC of 0.912 with 82.9% sensitivity and 88.2% specificity.

Conclusion

The panel of serum Linc00152, UCA1, and AFP demonstrates a novel and noninvasive biomarker with relatively high sensitivity and specificity for HCC diagnosis.

Toosendanin induces apoptosis of MKN‑45 human gastric cancer cells partly through miR‑23a‑3p‑mediated downregulation of BCL2

Toosendanin (TSN) is a tetracyclic triterpenoid extracted from Melia toosendan Sieb, et Zucc, which primarily grows in specific areas of China. Although toosendanin (TSN) exerts antitumoral effects on various human cancer cells, its influence on gastric cancer (GC) is remains to be elucidated. MicroRNAs (miRNAs/miRs) serve crucial roles in apoptosis and proliferation of cancer cells. miR-23a-3p has been shown to be associated with human GC; however, the specific function of miR-23a-3p in GC remains unclear. Therefore, the present study aimed to elucidate the role of miR-23a-3p in the regulation of GC cell proliferation and apoptosis induced in vitro by TSN treatment. Subsequently, apoptosis-related genes expression levels were quantified by reverse transcription-quantitative PCR and western blot analysis, respectively, and the target relationship between miR-23a-3p and BCL2 was determined by luciferase reporter gene analysis. Additionally, cell proliferation and apoptosis experiments were carried out. The results indicated that TSN inhibited proliferation and induced apoptosis in MKN-45 cells. Moreover, it upregulated the expression of miR-23a-3p. B-cell lymphoma-2 (BCL2) was identified as a potential target gene of miR-23a-3p, which was demonstrated to bind to the 3′-untranslated region of BCL2 mRNA, as detected by the luciferase reporter assay. Further studies revealed that BCL2 expression was downregulated following overexpression of miR-23a-3p. In addition, the overexpression of the miR-23a-3p inhibited proliferation, induced G₁ arrest and increased apoptosis in MKN-45 cells. The results of the present study demonstrated that miR-23a-3p inhibited proliferation and induced apoptosis of GC cells, which may be attributable to its direct targeting of BCL2. These results may provide a novel insight into the apoptosis of GC cells, and may lead to investigations into the mechanisms of the effects of TSN.

LncRNAs adjacent to pepsinogen C in gastric diseases and diagnostic efficiencies of joint detection in gastric diseases

Aims: We aimed to explore diagnostic efficiencies of long noncoding RNAs (lncRNAs) adjacent to PGC combining with sPGC and anti-Helicobacter pylori IgG in identifying GC (gastric cancer) and precancerous disease. Patients & methods: A total of 265 patients with different gastric diseases were collected. ELISA was to detect sPGC and anti-H. pylori IgG. LncRNAs was determined by qRT-PCR. Results: The area under receiver operating characteristic curve of lncRNAs in discriminating GC+AG (atrophic gastritis) and superficial gastritis (SG) were 79.0, 68.1 and 75.9%. The diagnostic performance of lncRNAs with sPGC had increasing trends in distinguishing GC from non-GC, SG from GC+AG comparing with lncRNAs, with no statistic difference. Diagnosis efficacies of lncRNAs with anti-H. pylori IgG improved dramatically. Conclusions: Serum lncRNAs could distinguish GC, AG and SG. Diagnosis efficiencies of lncRNAs with sPGC and anti-H. pylori-IgG could be improved.

The correlation between lncRNAs and Helicobacter pylori in gastric cancer

Helicobacter pylori infection performs a key role in gastric tumorigenesis. Long non-coding RNAs (lncRNAs) have demonstrated a great potential to be regarded as effective malignancy biomarkers for various gastrointestinal diseases including gastric cancer (GC). The present review highlights the relationship between lncRNAs and H. pylori in GC. Several studies have examined not only the involvement of lncRNAs in H. pylori-associated GC progression but also their molecular mechanisms of action. Among the pertinent studies, some have addressed the effects of H. pylori infection on modulatory networks of lncRNAs, while others have evaluated the effects of changes in the expression level of lncRNAs in H. pylori-associated gastric diseases, especially GC. The relationship between lncRNAs and H. pylori was found to be modulated by various molecular pathways.

Transcriptome hallmarks in Helicobacter pylori infection influence gastric cancer and MALT lymphoma

Aim: Altered long noncoding RNA (lncRNA) and mRNA is vital in the progression from Helicobacter pylori (H. pylori, HP) infection to gastric cancer (GC) and mucosa-associated lymphoid tissue (MALT) lymphoma. Materials & methods: Five independent Gene Expression Omnibus datasets (GSE5081, GSE84433, GSE15459, GSE66229 and GSE25638) were included in our study. Results: Differentially expressed lncRNAs and mRNAs in both H. pylori-positive gastritis and GC tissues were identified. Using two GC cohorts, the H. pylori-related mRNA DYNC1I1 and MMP7 were independent predictors of overall survival. Moreover, the expressions of lncRNA GHRLOS and 44 mRNAs were significantly changed in gastric MALT lymphoma patients. Conclusion: The lncRNA/mRNA response to H. pylori infection in gastritis and GC influence the outcome of GC and progression of MALT lymphoma.

Long non-coding RNA signature in gastric cancer

Gastric cancer as a common human malignancy has been associated with aberrant expressions of several coding and non-coding genes. Long non-coding RNAs (lncRNAs) as regulators of gene expressions at different genomic, transcriptomic and post-transcriptomic levels are among putative biomarkers and therapeutic targets in gastric cancer. In the present study, we have searched available literature and listed lncRNAs that are involved in the pathogenesis of gastric cancer. In addition, we discuss associations between expressions of these lncRNAs and tumoral features or risk factors for gastric cancer. Based on the established role of lncRNAs in regulation of genomic stability, cell cycle, apoptosis, angiogenesis and other aspects of cell physiology, the potential of these transcripts as therapeutic targets in gastric cancer should be evaluated in future studies.

LncRNA H19 induced by helicobacter pylori infection promotes gastric cancer cell growth via enhancing NF-κB-induced inflammation

Background

The aim of this study was to investigate the role of long non-coding RNA (lncRNA) H19 in gastric cancer (GC) with Helicobacter pylori (H. pylori).

Methods

H19 expression in peripheral blood from H. pylori+/- GC patients and healthy donors (control) as well as in GC tissues and cells were detected by qRT-PCR. Cell proliferation was evaluated by CCK-8 assay. Cell migration and invasion were evaluated by Transwell assay. The levels of pro-inflammatory cytokines were determined by ELISA. The protein levels of IκBα, p-IκBα and p65 were determined by western blotting.

Results

H19 expression was upregulated in H. pylori-infected GC tissues and cells. Furthermore, H. pylori promoted GC cell viability, migration, invasion and inflammatory response. Moreover, H19 overexpression promoted the proliferation, migration and invasion of H. pylori-infected GC cells via enhancing NF-κB-induced inflammation.

Conclusions

LncRNA H19 promotes H. pylori-induced GC cell growth via enhancing NF-κB-induced inflammation.

LncRNAs as potential diagnostic and prognostic biomarkers in gastric cancer: A novel approach to personalized medicine

Gastric cancer is the third leading cause of cancer death with 5-year survival rate of about 30-35%. Since early detection is associated with decreased mortality, identification of novel biomarkers for early diagnosis and proper management of patients with the best response to therapy is urgently needed. Long noncoding RNAs (lncRNAs) due to their high specificity, easy accessibility in a noninvasive manner, as well as their aberrant expression under different pathological and physiological conditions, have received a great attention as potential diagnostic, prognostic, or predictive biomarkers. They may also serve as targets for treating gastric cancer. In this review, we highlighted the role of lncRNAs as tumor suppressors or oncogenes that make them potential biomarkers for the diagnosis and prognosis of gastric cancer. Relatively, lncRNAs such as H19, HOTAIR, UCA1, PVT1, tissue differentiation-inducing nonprotein coding, and LINC00152 could be potential diagnostic and prognostic markers in patients with gastric cancer. Also, the impact of lncRNAs such as ecCEBPA, MLK7-AS1, TUG1, HOXA11-AS, GAPLINC, LEIGC, multidrug resistance-related and upregulated lncRNA, PVT1 on gastric cancer epigenetic and drug resistance as well as their potential as therapeutic targets for personalized medicine was discussed.

Identification of long noncoding RNA RP11-169F17.1 and RP11-669N7.2 as novel prognostic biomarkers of stomach adenocarcinoma based on integrated bioinformatics analysis

Aim: We aim to identify differentially expressed long noncoding RNAs (lncRNAs) and explored their functional roles in stomach adenocarcinoma. Materials & methods: Based on public omics data, we identified disregulated lncRNAs and investigated their prognostic values and potential functions based on ceRNA hypothesis. Results: Among the 52 differentially expressed lncRNAs, upregulated RP11-169F17.1 and RP11-669N7.2 were significantly associated with both poor overall survival and disease-free survival. RP11-169F17.1 and RP11-669N7.2 strongly correlated with microRNAs in cancer, cell proliferation and differentiation. RP11-169F17.1 and RP11-669N7.2 closely related to Helicobacter pylori infection-induced gastritis, duodenal ulcer, gastric cancer and mucosa-associated lymphoid tissue lymphoma. Conclusion: RP11-169F17.1 and RP11-669N7.2 act as novel prognostic biomarkers of stomach adenocarcinoma and may also play an important role in H. pylori infection-induced gastric diseases.

Improved characterization of the relationship between long intergenic non-coding RNA Linc00152 and the occurrence and development of malignancies

Linc00152, located on chromosome 2p11.2, is a long intergenic non-coding RNA molecule with 828 nucleotides that is highly expressed in many types of human tumor tissues, especially in malignant tumors of the digestive system. Linc00152 promotes the occurrence and development of tumors by increasing tumor cell proliferation, invasion, metastasis, and apoptosis. Additionally, linc00152 contributes to the carcinogenesis of several cancers, including gastric cancer, liver cancer, hepatocellular carcinoma, gallbladder cancer, clear cell renal cell carcinoma, and colorectal cancer, by disturbing various signaling pathways (eg PI3K/AKT, mTOR, IL-1, and NOTCH 1 signaling pathways). High linc00152 expression levels are associated with chemoresistance as well as poor prognosis and shorter survival. Continual advances made in the relevant research have indicated that linc00152 may be useful as a new tumor molecular biomarker, applicable for tumor diagnosis, targeted therapy, and prognosis assessment. This review summarizes the progress in the research into the relationship between linc00152 and the occurrence and development of malignancies based on molecular functions, regulatory mechanisms, and clinical applications.

Upregulation of long noncoding RNA LINC00152 promotes proliferation and metastasis of esophageal squamous cell carcinoma

Purpose: Esophageal cancer is a major cause of cancer-related mortality worldwide. The long noncoding RNA LINC00152 has been confirmed to play an oncogenic role in many cancers. However, the expression pattern and function of LINC00152 in human esophageal squamous cell carcinoma (ESCC) remain unclear.

Materials and methods: We evaluated LINC00152 expression in ESCC by qPCR and in situ hybridization. Proliferation, apoptosis, cell cycle, migration and invasion were examined in ESCC cells knocked down for LINC00152 knockdown by siRNA. Furthermore, an mRNA microarray was performed in ESCC cells with LINC00152 knockdown.

Results: LINC00152 was significantly upregulated in human ESCC clinical samples (P<0.001) and cell lines (P=0.008), and LINC00152 overexpression was related to lymphatic metastasis (P=0.03) and advanced pTNM classification (P=0.005). Furthermore, ESCC patients with LINC00152 overexpression had significantly shorter overall survival (P=0.007), and LINC00152 overexpression was an independent risk factor for overall survival of ESCC patients. LINC00152 knockdown inhibited the proliferation, migration and invasion of ESCC cells in vitro. In addition, mechanistic investigations through mRNA array and immunoblot analyses demonstrated that LINC00152 regulated the expression of several cell cycle-related proteins and SNARE (soluble N-ethylmaleimide-sensitive factor attachment protein receptors) interactions in vesicular transport pathway proteins.

Conclusion: Our research indicated that LINC00152 exhibits oncogenic functions in ESCC and may represent a potential new target for ESCC therapy.

ceRNA network construction and comparison of gastric cancer with or without Helicobacter pylori infection

Gastric cancer (GC) is a lethal disease, and among its variety of etiological factors, Helicobacter pylori (H. pylori) infection is the strongest risk factor. However, the genetic and molecular mechanisms underlying H. pylori-related GC need further elucidation. We investigated the competing endogenous RNA (ceRNA) network differences between H. pylori (+) and H. pylori (-) GC. The long noncoding RNA (lncRNA), microRNA (miRNA), and messenger RNA (mRNA) expression data from 32 adjacent noncancerous samples and 18 H. pylori (+) and 141 H. pylori (-) stomach adenocarcinoma samples were downloaded from the TCGA database. After construction of lncRNA-miRNA-mRNA ceRNA networks of H. pylori (+) and H. pylori (-) GC, Panther and Kobas databases were used to analyze the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Finally, survival analysis was used to discover the key genes. In H. pylori (+) GC, we identified a total of 1,419 lncRNAs, 82 miRNAs, and 2,501 mRNAs with differentially expressed profiles. In H. pylori (-) GC, 2,225 lncRNAs, 130 miRNAs, and 3,146 mRNAs were differentially expressed. Furthermore, three unique pathways (cytokine-cytokine receptor interaction, HIF-1 signaling pathway, and Wnt signaling pathway) were enriched in H. pylori (+) GC. According to the overall survival analysis, three lncRNAs (AP002478.1, LINC00111, and LINC00313) and two mRNAs (MYB and COL1A1) functioned as prognostic biomarkers for patients with H. pylori (+) GC. In conclusion, our study has identified the differences in ceRNA regulatory networks between H. pylori (+) and H. pylori (-) GC and provides a rich candidate reservoir for future studies.

LINC00152 promotes the growth and invasion of oral squamous cell carcinoma by regulating miR-139-5p

Background

LINC00152 plays a crucial role in tumorigenesis and progression of multiple types of cancer. However, the biological significance of LINC00152 and its potential role in oral squamous cell carcinoma (OSCC) remain to be determined. In the present study, we investigated the role of LINC00152 and the underlying mechanism of its oncogenic activity in OSCC.

Materials and methods

The expression of LINC00152 in OSCC tissues and cell lines was detected using qRT-PCR. Cell proliferation, colony formation, migration, and invasion were measured using a cell counting kit, colony formation assay, wound healing, and transwell invasion assays, respectively. The target gene of LINC00152 was confirmed using a dual-luciferase reporter assay and qRT-PCR. A nude mouse model was established to analyze the function of LINC00152 in vivo.

Results

LINC00152 expression was significantly upregulated in OSCC tissues and cell lines compared with that in normal counterparts. Upregulated LINC00152 served as an independent prognostic predictor in patients with OSCC. Moreover, knockdown of LINC00152 inhibited cell proliferation, colony formation, migration, and invasion, and suppressed the epithelial to mesenchymal transition in vitro, as well as impairing tumor growth in vivo. A mechanistic investigation indicated that LINC00152 could directly bind to miR-139-5p in OSCC. LINC00152 expression was inversely correlated with miR-139 expression in OSCC tissues.

Conclusion

Taken together, these results suggested that LINC00152 may function as oncogene in OSCC and could be a potential therapeutic target in patients with OSCC.

Diagnostic and prognostic value of circulating lncRNA H19 in gastric cancer

Gastric cancer (GC) is among the most frequent malignant diseases. Despite advances in treatment, the clinical outcome of patients with GC remains poor. The establishment of novel biomarkers is urgently required for early detection, treatment evaluation and prognostic assessment. Non-coding RNAs (ncRNAs) are a key topic of intensive research due to their potential applications in the field of oncology. The long ncRNA H19 has been frequently reported as overexpressed in many cancers including GC. In the present study, the diagnostic and prognostic value of circulating H19 in GC was assessed. Higher levels of circulating H19 were identified in GC patients (n=40) compared with a control group consisting of endoscopy-verified GC-free individuals (n=42; median levels relative to GAPDH, 58.4 vs. 29.9; P=0.027). Patients with smaller tumor sizes (<5 cm) exhibited higher H19 in their circulation compared with those with larger tumors (≥5 cm; P=0.04). Plasma levels of H19 declined significantly upon surgical removal of gastric tumors as documented in a subset of patients [n=20; relative median levels, 146.0 vs. 15.0 (pre-surgery); P=0.003]. However, it was identified that H19 had no prognostic role in GC by the Kaplan-Meier method. In conclusion, the present findings identify H19 as potential diagnostic marker in GC.

Long noncoding RNA LINC00152 promotes cell proliferation through competitively binding endogenous miR-125b with MCL-1 by regulating mitochondrial apoptosis pathways in ovarian cancer

Recently, an increasing number of studies have focused on the key function of long noncoding RNAs (lncRNAs) in biological activity. Abnormal lncRNA expression was found to relate to the development and pathogenesis of multiple cancers. LncRNA LINC00152 served as an oncogene in multiple cancers; however, its role in ovarian cancer remains unknown. In our research study, LINC00152 was upregulated in ovarian cancer tissues and cell lines. An increasing LINC00152 level was positively correlated with the histological grade, clinical stage, and poor prognosis of ovarian cancer patients. In addition, knockdown of LINC00152 reduced cell growth, induced cell apoptosis, and suppressed tumor growth. Moreover, we revealed that LINC00152 and Myeloid cell leukemia‐1 (MCL‐1) were targeted by miR‐125b and had the same miR‐125b combining site. The miR‐125b level was negatively correlated with the expression of LINC00152, while MCL‐1 was positively related to the LINC00152 level. MiR‐125b could affect LINC00152 levels as evaluated by qRT‐PCR. Finally, we affirmed that LINC00152 mediated cell proliferation by affecting MCL‐1 expression and MCL‐1‐mediated mitochondrial apoptosis pathways and by working as a competitive endogenous RNA (ceRNA) of miR‐125b. In summary, based on ceRNA theory, the combined research on miR‐125b and MCL‐1, and taking LINC00152 as a new study point, we provide new insight into the molecular mechanism of reversing cell proliferation in ovarian cancer.

LncRNA LINC00152 promoted glioblastoma progression through targeting the miR-107 expression

Long non-coding RNAs (lncRNAs) LINC00152 plays important roles in the progression of some tumors. However, the role of LINC00152 in human l glioblastoma is still unknown. In this study, we indicated that LINC00152 expression level was upregulated in glioblastoma tissues and cell lines. Overexpression of LINC00152 promoted the U87 and LN229 cell proliferation and invasion. Moreover, overexpression of LINC00152 suppressed the E-cadherin expression, where ectopic expression of LINC00152 promoted the N-cadherin, Vimentin, and Snail expression. These results suggested that LINC00152 enhanced epithelial-to-mesenchymal transition (EMT) program in the glioblastoma cell. Overexpression of LINC00152 suppressed the miR-107 expression in the U87 cell and enhanced the HMGA2 expression, which is a direct target gene of miR-107. In addition, we showed that the miR-107 expression was downregulated in the glioblastoma tissues and cell lines. Interesting, the expression of LINC00152 was negatively related with miR-107 expression in the glioblastoma tissues. Furthermore, LINC00152 promoted the glioblastoma cell proliferation and invasion through inhibiting miR-107 expression. These data suggested that LINC00152 acted as oncogene roles in the glioblastoma cell partly through targeting the miR-107 expression.

Long non-coding RNA-mediated regulation of signaling pathways in gastric cancer

Gastric cancer (GC) is one of the most common cancers globally. Because of the high frequency of tumor recurrence, or metastasis, after surgical resection, the prognosis of patients with GC is poor. Therefore, exploring the mechanisms underlying GC is of great importance. Recently, accumulating evidence has begun to show that dysregulated long non-coding RNAs (lncRNAs) participate in the progression of GC via several typical signaling pathways, such as the AKT and MAPK signaling pathways. Moreover, the interactions between lncRNAs and microRNAs appear to represent a novel mechanism in the pathogenesis of GC. This review provides a synopsis of the latest research relating to lncRNAs and associated signaling pathways in GC.

Liquid biopsy provides new insights into gastric cancer

Liquid biopsies have great promise for precision medicine as they provide information about primary and metastatic tumors via a minimally invasive method. In gastric cancer patients, a large number of blood-based biomarkers have been reported for their potential role in clinical practice for screening, early diagnosis, prognostic evaluation, recurrence monitoring and therapeutic efficiency follow-up. This current review focuses on blood liquid biopsies' role and their clinical implications in gastric cancer patients, with an emphasis on circulating tumor cells (CTCs), circulating tumor DNA (ctDNA) and circulating non-coding RNAs (ncRNAs). We also provide a brief discussion of the potential and limitations of liquid biopsies use and their future use in the routine clinical care of gastric cancer.

Linc00152 suppresses apoptosis and promotes migration by sponging miR-4767 in vascular endothelial cells

Dysfunction of vascular endothelial cells (VECs), such as increased apoptosis and diminished migration, is closely connected with most cardiovascular diseases and angiogenesis-related events. LncRNAs have been involved in regulation of many pathological processes, but their roles in vascular endothelial function are hardly underreported. Here, we explore the role of a intergenic lncRNA named linc00152 in the apoptosis and migration of VECs. We found that linc00152 was downregulated in human umbilical vein VECs (HUVECs) in a dose- and time-dependent manner following treatment with oxLDL, which is a typical proinflammatory factor in the initiation and progression of vascular endothelial dysfunction. Gain- and loss-function experiments indicated that linc00152 distinctly inhibited apoptosis and improved migration in oxLDL-treated HUVECs. By sponging miR-4767, linc00152 positively regulated the expression of Bcl2L12 and EGFR proteins. Moreover, blocking miR-4767 rescued the decrease of Bcl2L12 and EGFR caused by linc00152 knockdown, as well as the changes in cell apoptosis and migration. Our findings propose a novel role of linc00152 in the improvement of vascular endothelial function and a potential target for the therapy of some cardiovascular diseases.

The prognostic role of MAC30 in advanced gastric cancer patients receiving platinum-based chemotherapy

AIM

We aimed to investigate a practical profile of MAC30 on chemotherapeutic response in gastric cancer (GC).

PATIENTS & METHODS

We elected 87 GC patients receiving platinum-based chemotherapy in this study. MAC30 levels in tumor and adjuvant nontumor tissues were confirmed via reverse transcription-PCR to identify the clinical profile in GC and the correlation with therapeutic response.

RESULTS

We found elevated MAC30 in GC compared with the matched adjacent nontumor tissues. GC with enhanced MAC30 exhibited poorer survival by Kaplan-Meier analysis and poor response to adjuvant platinum-based chemotherapy. A multivariate analysis showed that MAC30 was an independent prognostic factor of overall survival in GC receiving platinum-based chemotherapy.

CONCLUSION

MAC30 could play as a potential biomarker for prognosis of GC with platinum-based chemotherapy.

The prognostic effect of LINC00152 for cancer: a meta-analysis

No meta-analysis has been performed to evaluate the association between LINC00152 and the survival of patients with cancers. We thus carried out this study. The online databases, such as PubMed, EMBASE, and the Cochrane controlled trials register, were searched to identify relevant articles. Dichotomous data were analyzed using the odds ratio (OR) as the summary statistic. The association between LINC00152 and survival of cancer was analyzed by pooling the hazard ratio (HR) with its corresponding 95% confidence interval (CI). Nine studies with 862 patients with cancer were included in this meta-analysis. The expression of LINC00152 was not associated with the age of patients (OR = 0.79, 95% CI = 0.55–1.14) and gender (OR = 1.08, 95% CI = 0.74–1.58). However, we found significant positive associations between LINC00152 and lymph node metastasis (OR = 2.54, 95% CI = 1.54–4.18) and TNM stage (OR = 2.32, 95% CI = 1.36–3.93). Furthermore, the expression of LINC00152 was significantly associated with tumor recurrence (OR = 3.32, 95% CI = 1.98–5.57) and shorter OS (HR = 1.94, 95% CI = 1.25–3.02). In conclusion, the results of this meta-analysis suggest that LINC00152 might be a biomarker for shorter OS and tumor recurrence in cancers.

Linc00152 promotes Cancer Cell Proliferation and Invasion and Predicts Poor Prognosis in Lung adenocarcinoma

Background: The long non-coding RNA Linc00152 stimulates tumor progression in cancer. However, its clinical significance and biological functions in lung adenocarcinoma remains unknown. We evaluate the expression of Linc00152 in lung adenocarcinoma and its possible correlation with clinicopathologic features and patient survival to reveal its biological effects in cancer progression and prognosis. Methods: Total RNA extraction was performed on 110 pairs of lung adenocarcinoma and adjacent normal tissue samples, and then RT-qPCR was conducted. Chi-square test analysis was used to calculate the correlation between pathological parameters and the Linc00152 mRNA levels. Kaplan-Meier and Cox proportional hazards analyses were used to analyze the overall survival (OS) and disease-free survival (DFS) rates. We also detected the potential functional effects of overexpression and knockdown of Linc00152 in vitro cell proliferation, tumor cell invasion and migration, as well as in vivo nude mouse xenograft and metastasis models. Results: The Linc00152 expression levels were higher in lung adenocarcinoma samples than in the adjacent normal tissues. Linc00152 expression levels tightly correlated with lymph node metastasis station, remote metastasis and TNM staging. The Kaplan-Meier analysis suggested that high Linc00152 expression caused significantly poorer OS and DFS rates, and a multivariate analysis revealed that Linc00152 was an independent risk factor for both DFS and OS. Overexpression of Linc00152 in lung cancer cells stimulated proliferation, tumor cell invasion and migration. Knockdown of Linc00152 inhibited cell growth and cell invasion and migration. Finally, Linc00152 knockdown inhibited lung tumor growth and tumor metastasis in nude mice models. Conclusions: Our study suggests that Linc00152 independently predicts poor prognosis and promotes tumor progression in lung adenocarcinoma. Linc00152 needs to be considered as a potential molecular target in future cancer pharmacology.

LINC00152: A pivotal oncogenic long non-coding RNA in human cancers

In recent years, increasing evidence has shown the potential role of long non‐coding RNAs (lncRNAs) in multiple cancers. Deregulation of lncRNAs was detected being closely associated with many kinds of tumours where they can act as a tumour suppressor or accelerator. LINC00152 was identified as an oncogene involved in many kinds of cancers, such as gastric cancer, hepatocellular carcinoma, colon cancer, gallbladder cancer and renal cell carcinoma. Moreover, inhibition of LINC00152 can suppress proliferation, migration and invasion of the cancer cells. Increasing evidence has showed that LINC00152 may act as a diagnostic and prognostic biomarker for the above‐mentioned cancers. In our review, we summarize the recent research progress of the expression and role of LINC00152 in various kinds of cancers.

Long Non-Coding RNAs: Key Regulators of Epithelial-Mesenchymal Transition, Tumour Drug Resistance and Cancer Stem Cells

Epithelial mesenchymal transition (EMT), the adoption by epithelial cells of a mesenchymal-like phenotype, is a process co-opted by carcinoma cells in order to initiate invasion and metastasis. In addition, it is becoming clear that is instrumental to both the development of drug resistance by tumour cells and in the generation and maintenance of cancer stem cells. EMT is thus a pivotal process during tumour progression and poses a major barrier to the successful treatment of cancer. Non-coding RNAs (ncRNA) often utilize epigenetic programs to regulate both gene expression and chromatin structure. One type of ncRNA, called long non-coding RNAs (lncRNAs), has become increasingly recognized as being both highly dysregulated in cancer and to play a variety of different roles in tumourigenesis. Indeed, over the last few years, lncRNAs have rapidly emerged as key regulators of EMT in cancer. In this review, we discuss the lncRNAs that have been associated with the EMT process in cancer and the variety of molecular mechanisms and signalling pathways through which they regulate EMT, and finally discuss how these EMT-regulating lncRNAs impact on both anti-cancer drug resistance and the cancer stem cell phenotype.

MicroRNA-146a affects the chemotherapeutic sensitivity and prognosis of advanced gastric cancer through the regulation of LIN52

The present study aimed to evaluate the correlation between the expression of microRNA-146a (miR-146a) and its target gene, LIN52, in advanced gastric cancer, and determine their potential effects on chemotherapeutic sensitivity and prognosis. Total RNA was extracted from 93 tissue samples of advanced gastric cancer and corresponding adjacent non-tumor tissues to quantify the relative expression levels of miR-146a using reverse transcription-quantitative polymerase chain reaction analysis. The expression of LIN52 was detected in tumors and normal tissues using immunohistochemical analysis. Correlation analysis was performed to assess the correlation between the expression of miR-146a and LIN52 and clinicopathological parameters of gastric cancer, including clinical diagnostic specificity, clinical tumor-necrosis-metastasis staging, lymph node metastasis, differentiation grade, chemotherapeutic sensitivity and prognosis. The expression of miR-146a in advanced gastric cancer tissues was lower, compared with that in the adjacent non-tumor tissues, and was negatively correlated with lymph node metastasis (P<0.05). Gastric cancer tissues with a low expression level of miR146a exhibited an increased expression level of LIN52 (P<0.05). Receiver operating characteristic curve regression analysis showed that miR-146a had 98% sensitivity in distinguishing gastric cancer tissues and adjacent non-tumor tissues. A high expression of miR-146a in gastric cancer was associated with improved treatment efficacy in patients. The chemotherapeutic sensitivity of patients with tumors expressing high levels of miR-146a was significantly higher, compared with that of patients with tumors expressing low levels of miR-146a (P<0.05). The expression of miR-146a was low in advanced gastric cancer tissues. As a tumor suppressor gene in advanced gastric cancer, miR-146a had a significant negative correlation with LIN52. High expression levels of miR-146a in advanced gastric cancer tissue may be associated with improved treatment efficacy of chemotherapy, suggesting that miR-146a may be a molecular marker for the diagnosis, prediction of treatment efficacy and prognosis of advanced gastric cancer.