The novel role and function of LINC01235 in metastasis of gastric cancer cells by inducing epithelial-mesenchymal transition.

LncRNAs play a vital role in the tumorigenesis of gastric cancer (GC). This study determined that LINC01235 expression has greater fold changes by analyzing TCGA RNA-Seq data. The qRT-PCR assay confirmed that LINC01235 is significantly over-expressed in GC cells and tissues. Additionally, the overall survival analysis showed that patients with a higher LINC01235 expression had a poorer prognosis than those with a lower LINC01235 expression. Univariate Cox regression analysis indicated that high LINC01235 expression is positively correlated with poor prognosis. Moreover, LINC01235 was an independent poor prognostic marker for GC in multivariate Cox analysis. Invitro assays suggested that LINC01235 knockdown suppresses GC cell migration and invasion. GSEA revealed that high LINC01235 expression is strongly enriched in the EMT pathway. Western blotting results revealed that LINC01235 silencing decreases the expression of EMT-induced proteins. In conclusion, LINC01235 can promote GC cell metastasis via EMT and function as a prognostic biomarker.

DLX6-AS1/miR-204-5p/OCT1 positive feedback loop promotes tumor progression and epithelial-mesenchymal transition in gastric cancer.

BACKGROUND: Accumulating evidence indicates that long non-coding RNAs (lncRNAs) participate in progression of gastric cancer (GC). Nevertheless, the function and expression level of DLX6-AS1 in GC remain unknown. METHODS: We explored the sequencing data of DLX6-AS1 downloaded from The Cancer Genome Atlas. The expression of DLX6-AS1, miR-204-5p and OCT1 in 56 GC patients and GC cell lines was quantified by qRT-PCR and western blotting. Furthermore, we performed in vitro functional assays to assess proliferation, invasion and migration of GC cells by knockdown of DLX6-AS1. The expression level of epithelial-mesenchymal transition (EMT)-related genes was also determined by qRT-PCR and western blotting. Actin remodeling was detected by F-actin phalloidin staining. The luciferase reporter assay and chromatin immunoprecipitation assay was utilized to confirm the bioinformatic prediction. The function of the DLX6-AS1/miR-204-5p/OCT1 axis in GC proliferation was clarified by rescue assays. RESULTS: We first demonstrated that DLX6-AS1 was upregulated in GC tissues and cell lines and was associated with T3/T4 invasion, distant metastasis and poor clinical prognosis. Further functional analysis showed that downregulation of DLX6-AS1 inhibited GC cell proliferation, migration, invasion and EMT in vitro. Mechanistic investigation indicated that DLX6-AS1 acted as a cancer-promoting competing endogenous RNA (ceRNA) by binding miR-204-5p and upregulating OCT1. Moreover, the transcription factor OCT1 was confirmed to enhance DLX6-AS1 expression by targeting the promoter region. CONCLUSIONS: This study revealed that OCT1-induced DLX6-AS1 promoted GC progression and the EMT via the miR-204-5p/OCT1 axis, suggesting that this lncRNA might be a promising prognostic biomarker and therapeutic target for GC.

ZEB1-AS1 initiates a miRNA-mediated ceRNA network to facilitate gastric cancer progression.

BACKGROUND: Currently, cancer-related competing endogenous RNA (ceRNA) networks are attracting significant interest. As long noncoding RNA ZEB1-AS1 has been reported to function as an oncogene due to sponging microRNAs (miRNAs) in several cancers, we hypothesized that it could interact with specific miRNAs to form regulatory networks and facilitate the growth of gastric cancer (GC). METHODS: MiRNAs interacting with ZEB1-AS1 were screened for and selected by bioinformatics analysis. Overexpression or repression of ZEB1-AS1 was performed to determine whether it could regulate selected miRNAs. Quantitative real-time polymerase chain reactions (qPCR) validated the expression profiles of ZEB1-AS1 and miR-149-3p in GC cell lines and tissue. Statistical analysis determined the clinical significance of ZEB1-AS1 in relation to miR-149-3p. Cell counting, wound healing and transwell assays were performed to assess cell proliferation, migration and invasion. A luciferase reporter assay was utilized to confirm the putative miR-149-3p-binding sites in ZEB1-AS1. RESULTS: Briefly, bioinformatics analysis inferred that ZEB1-AS1 interacts with miR-204, miR-610, and miR-149. Gain- or loss-of function assays suggested that ZEB1-AS1 negatively regulates miR-149-3p, miR-204-5p and miR-610 in GC cells. Validated by qPCR, ZEB1-AS1 was up-regulated and miR-149-3p down-regulated in GC cells and tissue. Data analyses indicated that ZEB1-AS1 and miR-149-3p are associated with the independent diagnosis and prognosis of GC. Functional assays support the theory that miR-149-3p hinders GC proliferation, migration and invasion, whereas its overexpression abrogates the corresponding effects induced by ZEB1-AS1. Lastly, dissection of the molecular mechanisms involved indicated that ZEB1-AS1 can regulate GC partly via a ZEB1-AS1/miR-149-3p axis. CONCLUSIONS: ZEB1-AS1 can interact with specific miRNAs, forming a miRNA-mediated ceRNA network and promoting GC progress, partly through a ZEB1-AS1/miR-149-3p axis.

Correction to: ZEB1­AS1 initiates a miRNA­mediated ceRNA network to facilitate gastric cancer progression.

[This corrects the article DOI: 10.1186/s12935-019-0742-0.].

Downregulation of microRNA-376a in Gastric Cancer and Association with Poor Prognosis.

BACKGROUND/AIMS: MicroRNAs have a significant role in the tumorigenesis and progression of cancers, including gastric cancer (GC). Our study aimed to identify a novel biomarker to predict the prognosis of patients with GC. METHODS: The GC microarray dataset, GSE28700, was downloaded from the Gene Expression Omnibus (GEO) database and screened for differentially expressed miRNAs (DEMs). The downregulation of miR-376a expression was verified in GC cell lines and 82 paired GC tissues by performing RT-qPCR and the correlation between its expression and clinicopathological characteristics was also explored. The target genes of miR-376a were predicted using TargetScan7.1, miRDB, and DIANA website tools. A functional enrichment analysis was performed to explore the biological role of the common target genes. RESULTS: Bioinformatics analysis found that miR-376a was downregulated in GC tissues. Compared with the control group, RT-qPCR results showed that the expression of miR-376a in GC cell lines and tissues were also significantly decreased. The expression of miR-376a was statistically associated with T and N stage. Survival analysis with Kaplan-Meier showed that GC patients in the low expression group had a poorer prognosis than those in the high expression group (median survival of 26.4 and 46.9 months, respectively). Univariate and multivariate analysis demonstrated that low miR-376a expression was an independent prognostic marker for poor survival. Functional enrichment analysis indicated that the common targets genes were involved in cell-cell communication, VEGF and mTOR1-mediated signaling, and epithelial-to-mesenchymal transition (EMT). CONCLUSION: The results suggest that miR-376a could play an important role in the tumorigenesis and progression of GC and act as a novel therapeutic target and prognostic indicator in patients with GC.

miR-1236-3p inhibits invasion and metastasis in gastric cancer by targeting MTA2.

BACKGROUND: MicroRNAs deregulation are common in human tumor progression. miR-1236-3p has been reported to function as tumor suppressor microRNA in various malignancies. The aim of this study was to demonstrate the downregulated expression of miR-1236-3p in gastric cancer (GC) tissues and cell lines, and clarify its biological function in GC. METHODS: Real-time polymerase chain reaction was used to measure the mRNA level of miR-1236-3p in GC. Dual luciferase assay was used to demonstrate that MTA2 was one of the candidate target genes of miR-1236-3p. Western blots were utilized to detect the protein levels. Cell function assays were also performed to determine the function of miR-1236-3p in GC. RESULTS: miR-1236-3p expression, which was associated with lymph node metastasis, differentiation and clinical stage, was significantly reduced in GC tissues and cell lines. miR-1236-3p over-expression could inhibit GC cell proliferation, migration and invasion, and inhibition of miR-1236-3p expression had opposite effects. Furthermore, we demonstrated that MTA2 was a candidate target of miR-1236-3p, and miR-1236-3p over-expression significantly inhibited the process of epithelial-mesenchymal transition. We also found that miR-1236-3p could suppress the PI3K/Akt signaling pathway in GC cells. CONCLUSIONS: Our results suggest that miR-1236-3p functions as a tumor suppressor in GC and could be a promising therapeutic target for GC.

Up-regulation of CRKL by microRNA-335 methylation is associated with poor prognosis in gastric cancer.

BACKGROUND: MicroRNAs have been suggested to play a vital role in regulating carcinogenesis, tumor progression and invasion. MiR-335 is involved in suppressing metastasis and invasion in various human cancers. However, the mechanisms responsible for the aberrant expression of miR-335 in gastric cancer (GC) remain unknown. METHODS: Expression of miR-335 in four GC cell lines and 231 GC tissues was determined by real-time quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR). DNA methylation status in the CpG islands upstream of miR-335 in GC cell lines and tissues was determined by methylation-specific PCR and bisulfite sequence-PCR. The effects of the demethylating agent 5-aza-2'-deoxycytidine on cell proliferation, apoptosis, cell cycle, migration, and invasion were investigated in GC cell lines. RESULTS: Cancer-specific methylation was detected in the upstream CpG-rich regions of miR-335, which dramatically silenced its transcriptional activity in GC cell lines and tissues. Low levels of miR-335 expression and high levels of miR-335 methylation in GC tissues were associated with poor clinical features and prognosis. Restoration of miR-335 expression in GC cells promoted cell apoptosis, inhibited tumor cell migration, invasion, and proliferation, and arrested the cell cycle at G0/G1 phase. Overexpression of miR-335 significantly reduced the activity of a luciferase reporter containing the 3' untranslated region of V-crk avian sarcoma virus CT10 oncogene homolog-like (CRKL). CONCLUSIONS: MiR-335 functions as a tumor suppressor and may be silenced by promoter hypermethylation. It plays a role in inhibiting tumor cell migration, invasion, and proliferation, arresting the cell cycle at G0/G1 phase, and promoting apoptosis in GC cells through targeting CRKL.

Type D personality is associated with delaying patients to medical assessment and poor quality of life among rectal cancer survivors.

OBJECTIVE: The aim of this research was to explore quality of life (QoL), mental health status, type D personality, symptom duration, and emergency admissions of Chinese rectal cancer patients as well as the relationship between these factors. METHODS: Type D personality was measured with the 14-item Type D Personality Scale (DS14). Mental health status was measured with the Hospital Anxiety and Depression Scale (HADS). The QoL outcomes were assessed longitudinally using the European Organization for Research and Treatment of Cancer QLQ-C30 and QLQ-CR38 questionnaires at the baseline and 6 months after diagnosis. RESULTS: Of the 852 survivors who responded (94 %), 187 (22 %) had a type D personality. The proportion of patients with duration of symptoms >1 month and being diagnosed after emergency admissions in type D group is significantly higher than that in non-type D group. At both of the time points, type D patients reported statistically significant lower scores on most of the functional scales, global health status/QoL scales, and worse symptom scores compared to patients without a type D personality. At the 6-month time point, a higher percentage of patients in the type D group demonstrated QoL deterioration. Clinically elevated levels of anxiety and depression were more prevalent in type D than in non-type D survivors. CONCLUSIONS: Type D personality was associated with poor QoL and mental health status among survivors of rectal cancer, even after adjustment for confounding background variables. Type D personality might be a general vulnerability factor to screen for subgroups at risk for longer symptom duration and emergency admissions in clinical practice.

Comparison of efficacy and safety between robotic-assisted versus laparoscopic surgery for locally advanced mid-low rectal cancer following neoadjuvant chemoradiotherapy: a systematic review and meta-analysis.

BACKGROUND: To some extent, robotic technique does offer certain benefits in rectal cancer surgery than laparoscopic one, while remains a topic of ongoing debate for rectal cancer patients who had undergone neoadjuvant chemoradiotherapy (NCRT). METHODS: Potential studies published until January 2024 were obtained from Web of Science, Cochrane Library, Embase and PubMed. Dichotomous and continuous variables were expressed as odds ratios (ORs) and weighted mean differences (WMDs) with 95% their confidence intervals (CIs), respectively. A random effects model was used if I2 statistic >50%, otherwise a fixed effects model. RESULTS: Eleven studies involving 1079 patients were analyzed. The robotic-assisted group had an 0.4 cm shorter distance from anal verge (95% CI: -0.680 to -0.114, P=0.006) and 1.94 times higher complete total mesorectal excision (TME) rate (OR=1.936, 95% CI: 1.061 to 3.532, P=0.031). However, the operation time in the robotic-assisted group was 54 minutes longer (95% CI: 20.489 to 87.037, P=0.002) than laparoscopic group. In addition, the robotic-assisted group had a lower open conversion rate (OR=0.324, 95% CI: 0.129 to 0.816, P=0.017) and a shorter length of hospital stay (WMD=-1.127, 95% CI: -2.071 to -0.184, P=0.019). CONCLUSION: Robot-assisted surgery offered several advantages over laparoscopic surgery for locally advanced mid-low rectal cancer following NCRT in terms of resection of lower tumours with improved TME completeness, lower open conversion rate and shorter hospital stay, despite longer operative time.

Ubiquitin-specific proteases: From biological functions to potential therapeutic applications in gastric cancer.

Deubiquitination, a post-translational modification regulated by deubiquitinases, is essential for cancer initiation and progression. Ubiquitin-specific proteases (USPs) are essential elements of the deubiquitinase family, and are overexpressed in gastric cancer (GC). Through the regulation of several signaling pathways, such as Wnt/ß-Catenin and nuclear factor-κB signaling, and the promotion of the expression of deubiquitination- and stabilization-associated proteins, USPs promote the proliferation, metastasis, invasion, and epithelial-mesenchymal transition of GC. In addition, the expression of USPs is closely related to clinicopathological features, patient prognosis, and chemotherapy resistance. USPs therefore could be used as prognostic biomarkers. USP targeting small molecule inhibitors have demonstrated strong anticancer activity. However, they have not yet been tested in the clinic. This article provides an overview of the latest fundamental research on USPs in GC, aiming to enhance the understanding of how USPs contribute to GC progression, and identifying possible targets for GC treatment to improve patient survival.

Neoadjuvant chemotherapy for nonmetastatic esophago-gastric adenocarcinomas: a systematic review and meta-analysis.

OBJECTIVE: A systematic review and meta-analysis was performed to investigate the efficacy of neoadjuvant chemotherapy for nonmetastatic esophago-gastric adenocarcinomas. METHODS: Electronic databases were searched systematically from January 1980 to July 2012 and a total of 2,587 patients from 17 randomized controlled trials were subjected to meta-analysis. The odds ratios (ORs) for overall survival (OS) and progression-free survival (PFS) were calculated. RESULTS: Seventeen randomized controlled trials were obtained and various comparisons of treatment approaches were performed. Randomized controlled trials detected no differences in these comparisons: R0 resection for neoadjuvant chemotherapy versus none; Preoperative chemotherapy versus surgery alone: 3-year OS, 5-year OS, 5-year OS in Europe, 3-year PFS; Preoperative chemotherapy plus postoperative chemotherapy versus postoperative chemotherapy: 1-year OS, 5-year OS; Preoperative chemotherapy versus preoperative chemoradiotherapy: 3-year OS. Randomized controlled trials detected significant differences in these comparisons: Preoperative chemotherapy plus postoperative chemotherapy versus surgery alone: 3-year and 5-year PFS, 5-year OS; Subgroup analysis examining preoperative chemotherapy versus surgery alone: 5-year OS in Asia; Preoperative chemotherapy versus postoperative chemotherapy: 1-year OS. CONCLUSION: The current limited evidence suggests that preoperative chemotherapy can be applied to patients with nonmetastatic esophago-gastric adenocarcinomas (specifically, advanced esophago-gastric cancer). However, the results should be interpreted with caution because of the statistically low power and the heterogeneity among study designs; therefore, our results need validations in future studies.

Exposure to Commonly Used Drugs and the Risk of Gastric Cancer: An Umbrella Review of Meta-Analyses.

Recently, attention has been paid to some medications and gastric cancer (GC) risk. This review aimed to evaluate associations between commonly used drugs and GC risk and to grade evidence from published systematic reviews and meta-analyses. This umbrella review was registered in PROSPERO (CRD42022320276). The systematic reviews and meta-analyses of observational studies were retrieved by searching Embase, PubMed, and Web of Science. The evidence strength of commonly used drugs and GC risk was categorized into four grades: weak, suggestive, highly suggestive, and strong. Of 19 associations between commonly used drugs and GC risk and its subtypes, none was supported by convincing or highly suggestive evidence. The risk of GC related to non-steroidal anti-inflammatory drugs (NSAIDs), non-aspirin NSAIDs, and acid-suppressive drugs, as well as the risk of non-cardia GC related to NSAIDs and aspirin, was supported by suggestive evidence. The results showed that a reduced GC risk was associated with two drug types (NSAIDs and non-aspirin NSAIDs), and an increased GC risk was associated with acid-suppressing drugs at the suggestive evidence level. Moreover, NSAIDs and aspirin reduced non-cardia GC risk as supported by suggestive evidence. However, the evidence supporting statins or metformin in reducing GC risk was weak, and thus future studies are required to clarify these associations.

Role of N6-methyladenosine RNA modification in gastric cancer.

N6-methyladenosine (m6A) RNA methylation is the most prevalent internal modification of mammalian messenger RNA. The m6A modification affects multiple aspects of RNA metabolism, including processing, splicing, export, stability, and translation through the reversible regulation of methyltransferases (Writers), demethylases (Erasers), and recognition binding proteins (Readers). Accumulating evidence indicates that altered m6A levels are associated with a variety of human cancers. Recently, dysregulation of m6A methylation was shown to be involved in the occurrence and development of gastric cancer (GC) through various pathways. Thus, elucidating the relationship between m6A and the pathogenesis of GC has important clinical implications for the diagnosis, treatment, and prognosis of GC patients. In this review, we evaluate the potential role and clinical significance of m6A-related proteins which function in GC in an m6A-dependent manner. We discuss current issues regarding m6A-targeted inhibition of GC, explore new methods for GC diagnosis and prognosis, consider new targets for GC treatment, and provide a reasonable outlook for the future of GC research.

Correction to "MicroRNA-596 acts as a tumor suppressor in gastric cancer and is upregulated by promotor demethylation".

[This corrects the article on p. 1224 in vol. 25, PMID: 30886505.].

Correction to "Aberrant methylation of secreted protein acidic and rich in cysteine gene and its significance in gastric cancer".

[This corrects the article on p. 6713 in vol. 25, PMID: 31857774.].

Correction to "MicroRNA-320a suppresses tumor progression by targeting PBX3 in gastric cancer and is downregulated by DNA methylation".

[This corrects the article on p. 842 in vol. 11, PMID: 31662823.].

Correction to "Novel long non-coding RNA LINC02532 promotes gastric cancer cell proliferation, migration, and invasion in vitro".

[This corrects the article on p. 91 in vol. 11, PMID: 30788037.].

Exosomal circRNAs: A key factor of tumor angiogenesis and therapeutic intervention.

Over the last few decades, our understanding of the molecular mechanisms underlying tumor angiogenesis has advanced at a significant pace and the clinical translation of these mechanisms has benefited millions of patients. However, limited efficacy and the rapid expansion of drug resistance remain unresolved issues. Recent studies in both preclinical and clinical settings have revealed that circRNAs, as a novel identified non-coding RNA can mediate intercellular communication and regulate the microenvironment within tumors after being selectively packaged, secreted, and transmitted via exosomes. This review aims to provide a comprehensive understanding of how exosomal circRNAs orchestrate inducers and inhibitors of angiogenesis, including their functions, molecular mechanisms, and potential roles as diagnostic biomarkers and therapeutic targets. Finally, we discuss the technological advances in exosome functionalization and exosome-mimetic nanovesicles intending to improve the clinical translation of exosomal circRNAs.

The functional role of Pescadillo ribosomal biogenesis factor 1 in cancer.

Tumors are neogrowths formed by the growth of normal cells or tissues through complex mechanisms under the influence of many factors. The occurrence and development of tumors are affected by many factors. Pescadillo ribosomal biogenesis factor 1 (PES1) has been identified as a cancer-related gene. The study of these genes may open up new avenues for early diagnosis, treatment and prognosis of tumors. As a nucleolar protein and part of the Pes1/Bop1/WDR12 (PeBoW) complex, PES1 is involved in ribosome biogenesis and DNA replication. Many studies have shown that high expression of PES1 is often closely related to the occurrence, proliferation, invasion, metastasis, prognosis and sensitivity to chemotherapeutics of various human malignant tumors through a series of molecular mechanisms and signaling pathways. The molecules that regulate the expression of PES1 include microRNA (miRNA), circular RNA (circRNA), c-Jun, bromodomain-containing protein 4 (BRD4) and nucleolar phosphoprotein B23. However, the detailed pathogenic mechanisms of PES1 overexpression in human malignancies remains unclear. This article summarizes the role of PES1 in the carcinogenesis, prognosis and treatment of multiple tumors, and introduces the molecular mechanisms and signal transduction pathways related to PES1.