Advances in molecular biomarkers for gastric cancer: miRNAs as emerging novel cancer markers. Expert Rev Mol Med. 2014;16:e1. [PMID: 24456939 PMCID: PMC3908627 DOI: 10.1017/erm.2013.16]

Meta-analysis of FTO expression on the clinicopathologic characteristics and prognosis of gastric cancer

BACKGROUND

Fat mass and obesity-related gene (FTO) is aberrantly expressed in various cancers including highly expressed in gastric cancer tissues. The aim of this meta-analysis was to explore the effect of FTO expression on clinicopathological and prognostic outcome of gastric cancer.

METHODS

China National Knowledge Infrastructure (CNK), Wanfang database, VIP database, Chinese biomedical literature database (CBM), PubMed, Web of Science, the Cochrane library and EMBASE database were searched to screen the literatures according to the inclusion criteria. The search time was the database establishment until May 2023. The two researchers independently searched and screened the literature, extracted pathological data, and conducted The Newcastle-Ottawa scale (NOS) quality evaluation. Analyze the correlation between FTO and pathological indicators of gastric cancer patients and the impact on prognosis, use and Stata 12.0, software for Meta-analysis.

RESULTS

A total of 1619 patients were studied in this study. The results of the Meta-analysis showed that higher expression levels of FTO were associated with TMN stage (OR = 1.83, 95% CI: 1.11-3.03, P = .019), liver metastases (OR = 3.73, 95% CI: 1.49-9.31, P = .005), vascular invasion (OR = 2.22, 95% CI: 1.36-3.61, P = .001), poorer overall survival (OS) (HR = 0.46, 95% CI: 0.34-0.58, P < .001) and recurrence-free survival (HR = 0.56, 95% CI: 0.40-0.73, P < .001) in gastric cancer patients. There was no significant relationship with the degree of differentiation (OR = 1.08, 95% CI: 0.49-2.35, P = .852), age (OR = 0.89, 95% CI: 0.71-1.11, P = .306), and gender (OR = 0.92, 95% CI: 0.74-1.14, P = .432).

CONCLUSION

High expression of FTO was associated with risk of distant metastases and poor prognosis for patients with gastric cancer. FTO may be a potential prognostic biomarker for gastric cancer, but due to the limited number of literature, the above results need further research.

Long intergenic noncoding RNA for IGF2BP2 stability suppresses gastric cancer cell apoptosis by inhibiting the maturation of microRNA-34a

The oncogenic role of long intergenic noncoding RNA for IGF2BP2 stability (LINRIS) has been reported in colorectal cancer. This research aimed to study its potential involvement in gastric cancer (GC). In this study, paired GC and non-tumor tissues were obtained from 64 GC patients, and the levels of LINRIS, mature microRNA-34a (miR-34a), and miR-34a precursor in these tissues were measured with RT-qPCR. Linear regression was used to analyze their correlations. The role of LINRIS overexpression and siRNA silencing in regulating the maturation of miR-34a was analyzed by RT-qPCR. Cell apoptosis was studied with flow cytometry. It was observed that LINRIS was overexpressed in GC and showed a negative correlation with mature miR-34a, but not miR-34a precursor. In GC cells, LINRIS siRNA silencing upregulated mature miR-34a level, but not miR-34a precursor level. LINRIS overexpression downregulated miR-34a level. Cell apoptosis analysis showed that LINRIS siRNA silencing and miR-34a overexpression promoted GC cell apoptosis and suppressed cell migration and invasion, while LINRIS overexpression suppressed cell apoptosis and enhanced cell migration and invasion. In addition, the effect of LINRIS overexpression was reversed by miR-34a overexpression. Therefore, LINRIS siRNA silencing in GC may promote cell apoptosis by promoting miR-34a maturation.

Exosomal LINC00853 promotes progression of gastric cancer via the MAP17/PDZK1/AKT signaling pathway

Although rare, there is ongoing research into biomarkers that predict the onset and recurrence of gastric cancer, particularly focusing on substances found in exosomes. Long non-coding RNAs (lncRNAs) have garnered attention for their potential in diagnosing gastric cancer. This study investigates the role of lncRNAs in gastric cancer, focusing on their presence in exosomes as potential biomarkers for the disease's onset and recurrence. We utilized the ArrayStar Human LncRNA array 2.0 to analyze lncRNA expression in tissues from early-stage gastric cancer patients. Our analysis highlighted LINC00853, which was significantly upregulated in cancer tissues and implicated in promoting epithelial-mesenchymal transition via the MAP17/PDZK1/AKT pathway. Functional studies on AGS and MKN74 gastric cancer cell lines demonstrated that LINC00853 facilitates cell proliferation, invasion, and migration. Additionally, RNA immunoprecipitation and electrophoretic mobility shift assays confirmed LINC00853 interaction with MAP17. Importantly, LINC00853 was also detected in exosomes from both patient samples and cell lines, and its downregulation led to decreased tumorigenicity in AGS cells. These findings suggest that both cellular and exosomal LINC00853 contribute to gastric cancer pathogenesis and may serve as valuable biomarkers for the disease.

Elevated mRNA level indicates FSIP1 promotes EMT and gastric cancer progression by regulating fibroblasts in tumor microenvironment

Fiber sheath interaction protein 1 (FSIP1) plays a crucial role in cancer development and occurrence, but its influence on gastric cancer is still unclear. In this study, differential mRNA analysis was performed by TCGA database for the Limma analysis algorithm, and the gene ontology, the Kyoto Encyclopedia of Genes and Genomes, and the gene set enrichment analysis (GSEA) were used for bioinformatics functional enrichment analysis. A gastric cancer cell model with FSIP1 mRNA knockdown was constructed by RNA interference. Cell counting kit-8 and transwell migration/invasion assay were performed to verify the cell function, and western blotting was employed to confirm the expression of target genes. The GSEA analysis revealed that FSIP1 was associated with epithelial-mesenchymal transition (EMT). The high expression group also had a significant positive correlation with the markers of fibroblast in tumor microenvironment (TME). Western blotting showed that FSIP1 was generally upregulated in gastric cancer cell lines. FSIP1 mRNA knockdown cell lines inhibited gastric cells proliferation, migration, and metastasis in vitro, and the protein levels of EMT-related markers N-cadherin and vimentin were reduced. Our work proved that FSIP1 promoted EMT by regulating fibroblasts in the TME, thereby promoting the carcinogenic activity of cancer cells in proliferation, invasion, and migration. FSIP1 may take a role of the occurrence and could be a potential therapeutic target and offer a new insight into the underlying mechanism of gastric cancer.

Gastric cancer specific drug delivery with hydrophilic peptide probe conjugation

Cancer-specific diagnosis is challenging. Phage display is an approach that could contribute to finding new specific biomarkers. In this study, we developed a new peptide probe specific for gastric cancer and validated it for gastric cancer-specific theranostics. We isolated linear peptides by screening a combinatorial phage library for a cancer stem cell marker, LGR5 protein. Among these, peptides with high selectivity against gastric cancer cells were selected and examined for therapeutic poteintial in vitro as well as in vivo. Through leucine-rich G protein-coupled receptor 5 (LGR5) protein-based phage display, we obtained a hydrophilic 7-mer peptide sequence (STCTRSR, named STC). Both the STC-peptide-conjugated fluorescent dye and chlorin e6 (Ce6) displayed a significantly higher intensity in gastric cancer cells compared to that in healthy cells. In mice with gastric cancer, the fluorescence in the tumors was 3.4× more intense when treated with the Ce6-STC conjugate compared to that with free Ce6 and conferred higher phototoxicity after single laser irradiation. Repeated photodynamic therapy could further reduce the tumor volume after treating these mice with the Ce6-STC conjugate. The treatment with the Ce6-STC conjugate exhibited a significantly lower fluorescence in the liver than that with free Ce6. In conclusion, we confirmed that the STC peptide is a gastric cancer-specific probe that could be useful in gastric cancer theranostics. In conclusion, considering its targeting ability and hydrophilicity, various hydrophobic chemotherapeutic agents could be revisited for gastric cancer treatment in combination with the probe described in this study.

Comprehensive evaluation of serum circHAS2 as a novel diagnostic and prognostic biomarker for gastric cancer

The diagnosis and screening indicators for gastric cancer (GC) are not satisfactory, resulting in a large number of GC patients being missed and missing the best treatment time. Due to the special structure of circular RNAs (circRNAs), they have a more accurate and powerful ability to detect tumor occurrence. In addition, circHAS2 has been found to promote the proliferation, migration, and invasion of GC cells. Therefore, this study explored the potential of circHAS2 as a biomarker for GC. The expression level of circHAS2 in the specimens was detected by real-time fluorescent quantitative PCR. The molecular characteristics of circHAS2 were verified by agarose gel electrophoresis and Sanger sequencing. The feasibility of the circHAS2 detection method was verified by room temperature placement and repeated freezing and thawing. The diagnostic effect of circHAS2 on GC was evaluated by receiver-operating curve analysis. The correlation between circHAS2 expression level and clinical pathological parameters was analyzed using the χ2 -test. Kaplan-Meier survival curve analysis was used to analyze the survival situation of the circHAS2 high- and low-expression group. Univariate and multivariate Cox regression analysis was used to evaluate the influencing factors of prognosis in GC patients. CircHAS2 in cells can be secreted into the blood, and its expression level is significantly upregulated in the serum of patients with GC. The expression level of circHAS2 is correlated with the tissue differentiation, tumor node metastasis staging, classification, and lymph node metastasis of GC patients. CircHAS2 can effectively identify GC and even early GC. In addition, the expression levels of circHAS2 in postoperative GC patients significantly decreased and returned to normal after the second stage of chemotherapy. Finally, the circHAS2 low-expression group had better survival. The upregulated expression of circHAS2 in the serum of GC patients can effectively identify GC and early GC and can be used for effective monitoring of the prognosis of GC patients. In summary, circHAS2 can be used as an effective diagnostic and prognostic marker for GC.

Gastric Cancer Signaling Pathways and Therapeutic Applications

Gastric cancer (GC) is a prevalent malignant tumor and ranks as the second leading cause of death among cancer patients worldwide. Due to its hidden nature and difficulty in detection, GC has a high incidence and poor prognosis. Traditional treatment methods such as systemic chemotherapy, radiotherapy, and surgical resection are commonly used, but they often fail to achieve satisfactory curative effects, resulting in a very low 5-year survival rate for GC patients. Currently, targeted therapy and immunotherapy are prominent areas of research both domestically and internationally. These methods hold promise for the treatment of GC. This article focuses on the signaling pathways associated with the development of GC, as well as the recent advancements and applications of targeted therapy and immunotherapy. The aim is to provide fresh insights for the clinical treatment of GC.

A descriptive analysis of gastric cancer with an immunohistochemical Study of Ki67 and p53 as prognostic factors.: Bahrain experience

OBJECTIVES

To describe the increasing number of gastric cancer cases at Bahrain Defense Force Hospital with implementation of immunohistochemistry markers as prognostic factors.

METHODS

This study included histologically confirmed malignant gastric tumors diagnosed at Bahrain Defense Force Hospital from January 2009 to June 2019. Various epidemiological and pathological data were abstracted and recorded with immunohistochemical analysis of the proliferation marker Ki67 and cell-cycle regulator p53 as prognostic factors.

RESULTS

A total of 53 patients with gastric cancer were included in the study, with mean age of 59.75 ± 12.9 years. The typical histological types were signet ring cell adenocarcinoma (68%) and intestinal type adenocarcinoma (17%). Helicobacter pylori and intestinal metaplasia were significantly associated with gastric cancer (p<0.01). The studied population's mortality was 39 (74%). The Ki67 proliferation index showed a mean and standard deviation of 67.09 ± 16.338, with a higher mortality rate in patients with low Ki67 but no difference in survival time. No statistically significant association was found between clinicopathological findings with p53 immunostaining positivity.

CONCLUSION

The common gastric cancers are signet ring cell adenocarcinoma and intestinal type adenocarcinoma, affecting a wide range of age groups (33-91 years), with those over 60 years at greater risk. Interestingly, low Ki67 is associated with a higher mortality rate, whereas p53 has no prognostic significance. Expression of both Ki67 and p53 showed no association with survival time.

Therapeutic potential of toosendanin: Novel applications of an old ascaris repellent as a drug candidate

Toosendanin (TSN), extracted from Melia. toosendan Sieb.et Zucc. and Melia. azedarach L., has been developed into an ascaris repellent in China. However, with the improvement of public health protection, the incidence of ascariasis has been reduced considerably, resulting in limited medical application of TSN. Therefore, it is questionable whether this old ascaris repellent can develop into a drug candidate. Modern studies have shown that TSN has strong pharmacological activities, including anti-tumor, anti-botulinum, anti-viral and anti-parasitic potentials. It also can regulate fat formation and improve inflammation. These researches indicate that TSN has great potential to be developed into a corresponding medical product. In order to better development and application of TSN, the availability, pharmacodynamics, pharmacokinetics and toxicology of TSN are summarized systematically. In addition, this review discusses shortcomings in the current researches and provides useful suggestions about how TSN developed into a drug candidate. Therefore, this paper illustrates the possibility of developing TSN as a medical product, aimed to provide directions for the clinical application and further research of TSN.

Network and functional analyses of differentially expressed genes in gastric cancer provide new biomarkers associated with disease pathogenesis

BACKGROUND

Gastric cancer is a dominant source of cancer-related death around the globe and a serious threat to human health. However, there are very few practical diagnostic approaches and biomarkers for the treatment of this complex disease.

METHODS

This study aimed to evaluate the association between differentially expressed genes (DEGs), which may function as potential biomarkers, and the diagnosis and treatment of gastric cancer (GC). We constructed a protein-protein interaction network from DEGs followed by network clustering. Members of the two most extensive modules went under the enrichment analysis. We introduced a number of hub genes and gene families playing essential roles in oncogenic pathways and the pathogenesis of gastric cancer. Enriched terms for Biological Process were obtained from the "GO" repository.

RESULTS

A total of 307 DEGs were identified between GC and their corresponding normal adjacent tissue samples in GSE63089 datasets, including 261 upregulated and 261 downregulated genes. The top five hub genes in the PPI network were CDK1, CCNB1, CCNA2, CDC20, and PBK. They are involved in focal adhesion formation, extracellular matrix remodeling, cell migration, survival signals, and cell proliferation. No significant survival result was found for these hub genes.

CONCLUSIONS

Using comprehensive analysis and bioinformatics methods, important key pathways and pivotal genes related to GC progression were identified, potentially informing further studies and new therapeutic targets for GC treatment.

Screening and Bioinformatics Analyses of Key miRNAs Associated with Toll-like Receptor Activation in Gastric Cancer Cells

Background and Objectives: To screen key miRNAs and their target genes related to Toll-like receptor (TLR) activation in gastric cancer (GC) cells and analyze them bioinformatically. Materials and Methods: Venn diagrams were obtained to screen miRNAs that were upregulated/downregulated in both GSE54129 and GSE164174. The miRTarBase database was used to predict the target genes of upregulated miRNAs. The differentially expressed genes in the regulatory network were analyzed. miR-16-5p expression in different tissue samples and the variations in the methylation states of four hub genes were measured. Results: We found that GSE54129 included 21 normal gastric tissues and 111 gastric cancer tissues, GSE164174 included 1417 normal gastric tissues and 1423 gastric cancer tissues. Venn diagram analysis results showed that compared with the control group, a total of 68 DEmiRNAs were upregulated in the GSE54129 and GSE164174 datasets, and no common downregulated DEmiRNAs were found. On further analysis of the GSE108345 dataset, we obtained the competing endogenous RNA (ceRNA) network associated with the activation of TLRs, and listed the top 10 lncRNA–miRNA–mRNA networks, including 10 miRNAs, 86 mRNA and 134 lncRNAs. Cytological HuBBA scores yielded a total of 1 miRNA, 16 mRNAs and 45 lncRNAs, of which miR-16-5p scored the highest as it was considered a key miRNA for TLR activation in GC cells, which are important in response against microorganisms. The results of Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that endocytosis, microRNAs in cancer and the PI3K-Akt signaling pathway are related to TLR signaling. The results of in vivo experiments indicated that miR-16-5p was highly expressed in gastric cancer cells and tissues. Conclusions: Hsa-miR-16-5p’s target genes mainly play a role by regulating the expression of four genes—MCL1, AP2B1, LAMB1, and RAB11FIP2. The findings provide a scientific basis for the development of immunotherapy for GC.

Up-regulation of collagen type V alpha 2 (COL5A2) promotes malignant phenotypes in gastric cancer cell via inducing epithelial-mesenchymal transition (EMT)

Recent studies have reported that collagen type V alpha 2 (COL5A2) is a hub gene and associated with the prognosis of gastric cancer (GC) patients, playing an important role in GC. In this study, we aim to fathom out the biological roles of COL5A2 and its relevant mechanism in GC. Oncomine, gene expression profiling interactive analysis, and UALCAN were used to explore the effects of COL5A2 on GC. Cell counting kit-8 assay, colony formation assay, and transwell assay were conducted to investigate the biological behaviors of GC cell lines AGS and SGC-7901. Quantitative reverse transcription polymerase chain reaction and western blot were performed to determine gene and protein expressions. COL5A2 expression was up-regulated and negatively correlated with survival percentage of GC patients. COL5A2 expression was notably elevated in high stage and high grade of GC. Down-regulation of COL5A2 inhibited proliferation, migration, and invasion of AGS and SGC-7901 cells. COL5A2 induced epithelial-mesenchymal transition (EMT) by promoting the expressions of mesenchymal markers (SNAI1, SNAI2, TWIST, VIM, and MMP2), thereby facilitating the malignant phenotypes of GC. COL5A2 plays an oncogenic role in GC and has potential to predict the progression and prognosis of GC patients.

Genomic analysis of matrix metalloproteinases affecting the prognosis and immunogenic profile of gastric cancer

This study systematically and comprehensively analyzed the characteristics of matrix metalloproteinases (MMPs) in gastric cancer (GC) and revealed the relationship between MMPs and prognoses, clinicopathological features, tumor microenvironment, gene mutations, and drug therapy response in patients with GC. Based on the mRNA expression profiles of 45 MMP-related genes in GC, we established a model that classified GC patients into three groups based on cluster analysis of the mRNA expression profiles. The 3 groups of GC patients showed significantly different prognoses as well as tumor microenvironmental characteristics. Next, we used Boruta's algorithm and PCA method to establish an MMP scoring system and found that lower MMP scores were associated with better prognoses, lower clinical stages, better immune cell infiltration, lower degrees of immune dysfunction and rejection, and more genetic mutations. Whereas a high MMP score was the opposite. These observations were further validated with data from other datasets, showing the robustness of our MMP scoring system. Overall, MMP could be involved in the tumor microenvironment (TME), clinical features, and prognosis of GC. An in-depth study of MMP patterns can better understand the indispensable role of MMP in the development of GC and reasonably assess the survival prognosis, clinicopathological features, and drug efficacy of different patients, thus providing clinicians with a broader vision of GC progression and treatment.

Insights into the Relationship between Pentraxin-3 and Cancer

Although cancer can be cured if detected early and treated effectively, it is still a leading cause of death worldwide. Tumor development can be limited by an appropiate immune response, but it can be promoted by chronic extensive inflammation through metabolic dysregulation and angiogenesis. In the past decade, numerous efforts have been made in order to identify novel candidates with predictive values in cancer diagnostics. In line with this, researchers have investigated the involvement of pentraxin-3 (PTX-3) in cellular proliferation and immune escape in various types of cancers, although it has not been clearly elucidated. PTX-3 is a member of the long pentraxin subfamily which plays an important role in regulating inflammation, innate immunity response, angiogenesis, and tissue remodeling. Increased synthesis of inflammatory biomarkers and activation of different cellular mechanisms can induce PTX-3 expression in various types of cells (neutrophils, monocytes, lymphocytes, myeloid dendritic cells, fibroblasts, and epithelial cells). PTX-3 has both pro- and anti-tumor functions, thus dual functions in oncogenesis. This review elucidates the potential usefulness of PTX-3 as a serum biomarker in cancer. While future investigations are needed, PTX-3 is emerging as a promising tool for cancer's diagnosis and prognosis, and also treatment monitoring.

Nucleobindin-2/nesfatin-1 enhances the cell proliferation, migration, invasion and epithelial-mesenchymal transition in gastric carcinoma

Nesfatin-1, a newly discovered adipokine derived from nucleobindin-2 (NUCB2), has been described as a new prognostic marker in cancers. This study aimed to explore the functional role of NUCB2/nesfatin-1 in the cell proliferation, migration and invasion in gastric carcinoma (GC). The expressions of NUCB2/nesfatin-1 in GC tissues and normal adjacent tissues (NATs) were compared, and the effect of inhibition of NUCB2/nesfatin-1 on the cell proliferation, migration, invasion and epithelial-mesenchymal transition (EMT) in GC cell line SGC-7901 was investigated. Cell transfection was conducted to inhibit NUCB2/nesfatin-1 by short hairpin RNA. Cell proliferation, migration and invasion abilities were determined using cell counting kit-8 (CCK-8), 5-ethynyl-2'-deoxyuridine (EdU), wound healing and transwell assays, respectively. The expressions of EMT markers E-Cadherin and N-Cadherin were determined using western blotting. The expression of NUCB2/nesfatin-1 protein in GC tissues was significantly increased compared with that in NATs. Consistently, the serum concentrations of NUCB2/nesfatin-1 were significantly higher in patients with GC as compared with those in the control group. Moreover, the results of CCK-8 assay and EdU assay indicated that knockdown of NUCB2/nesfatin-1 could markedly decrease SGC-7901 proliferation. Furthermore, the results of wound healing assay and transwell assay demonstrated that knockdown of NUCB2/nesfatin-1 significantly suppressed SGC-7901 migration and invasion abilities. Additionally, knockdown of NUCB2/nesfatin-1 decreased the expressions of N-Cadherin and increased the expressions of E-Cadherin in SGC-7901 cells. These findings suggest that knockdown of NUCB2/nesfatin-1 suppressed the proliferation, migration, invasion and EMT of SGC-7901 cells, suggesting a potentially promising therapeutic target for GC.

MiR-550a-3p restores damaged vascular smooth muscle cells by inhibiting thrombomodulin in an <em>in vitro</em> atherosclerosis model

Thrombomodulin (TM) is involved in the pathological process of atherosclerosis; however, the underlying mechanism remains unclear. Oxidised low-density lipoprotein (Ox-LDL; 100 μg/mL) was used to induce human vascular smooth muscle cells (HVSMCs) into a stable atherosclerotic cell model. The expression levels of miR-550a-3p and TM were detected by real-time reverse transcription-polymerase chain reaction. Cell proliferation was estimated using CCK8 and EDU assays. Wound scratch and transwell assays were used to measure the ability of cells to invade and migrate. Propidium iodide fluorescence-activated cell sorting was used to detect apoptosis and cell cycle changes. A dual-luciferase reporter assay was performed to determine the binding of miR-550a-3p to TM. Our results suggested the successful development of a cellular atherosclerosis model. Our data revealed that TM overexpression significantly promoted the proliferation, invasion, migration, and apoptosis of HVSMCs as well as cell cycle changes. Upregulation of miR-550a-3p inhibited the growth and metastasis of HVSMCs. Furthermore, miR-550a-3p was confirmed to be a direct target of TM. Restoration of miR-550a-3p expression rescued the effects of TM overexpression. Thus, miR-550a-3p might play a role in atherosclerosis and, for the first time, normalised the function of injured vascular endothelial cells by simultaneous transfection of TM and miR-550a-3p. These results suggest that the miR-550a-3p/TM axis is a potential therapeutic target for atherosclerosis.

Neutrophile-to-lymphocyte, lymphocyte-to-monocyte, and platelet-to-lymphocyte ratios as prognostic and response biomarkers for resectable locally advanced gastric cancer

BACKGROUND

Perioperative fluorouracil plus leucovorin, oxaliplatin, and docetaxel (FLOT) improves prognosis in locally advanced gastric cancer (LAGC). Neutrophil-to-lymphocyte (NLR), lymphocyte-to-monocyte (LMR), and platelet-to-lymphocyte (PLR) ratios are prognostic biomarkers but not predictive factors.

AIM

To assess blood ratios’ (NLR, LMR and PLR) potential predictive response to FLOT and survival outcomes in resectable LAGC patients.

METHODS

This was a multicentric retrospective study investigating the clinical potential of NLR, LMR, and PLR in resectable LAGC patients, treated with at least one preoperative FLOT cycle, from 12 Portuguese hospitals. Means were compared through non-parametric Mann-Whitney tests. Receiver operating characteristic curve analysis defined the cut-off values as: High PLR > 141 for progression and > 144 for mortality; high LMR > 3.56 for T stage regression (TSR). Poisson and Cox regression models the calculated relative risks/hazard ratios, using NLR, pathologic complete response, TSR, and tumor regression grade (TRG) as independent variables, and overall survival (OS) as the dependent variable.

RESULTS

This study included 295 patients (mean age, 63.7 years; 59.7% males). NLR was correlated with survival time (r = 0.143, P = 0.014). PLR was associated with systemic progression during FLOT (P = 0.022) and mortality (P = 0.013), with high PLR patients having a 2.2-times higher risk of progression [95% confidence interval (CI): 0.89-5.26] and 1.5-times higher risk of mortality (95%CI: 0.92-2.55). LMR was associated with TSR, and high LMR patients had a 1.4-times higher risk of achieving TSR (95%CI: 1.01-1.99). OS benefit was found with TSR (P = 0.015) and partial/complete TRG (P < 0.001). Patients without TSR and with no evidence of pathological response had 2.1-times (95%CI: 1.14-3.96) and 2.8-times (95%CI: 1.6-5) higher risk of death.

CONCLUSION

Higher NLR is correlated with longer survival time. High LMR patients have a higher risk of decreasing T stage, whereas high PLR patients have higher odds of progressing under FLOT and dying. Patients with TSR and a pathological response have better OS and lower risk of dying.

High Expression of UPK3A Promotes the Progression of Gastric Cancer Cells by Inactivating p53 Pathway

Background

Gastric cancer is a common gastrointestinal tract cancer and is a considerable health burden worldwide. TCGA analysis found Uroplakin 3A (UPK3A) was upregulated in gastric cancer tissues. Our study was designed to investigate the underlying mechanism of Uroplakin 3A (UPK3A) in gastric cancer.

Methods

Data from TCGA database were used to assess the expression, and Kaplan-Meier plotter analysis was used to assess the prognosis value of UPK3A. Furthermore, there are effects of UPK3A silencing on the activity, proliferation, migration, and invasion of human gastric cancer cells (SNU-216 and HGC-27) using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), colony formation, wound healing, and Transwell assays. In addition, the expression of UPK3A, p53, KLF4, ZMAT3, MDM2, and SP1 was detected by qRT-PCR and Western blot assay.

Results

UPK3A was markedly upregulated in gastric cancer tissues compared to that in normal tissues, and patients with high UPK3A level showed poor prognosis. UPK3A was highly expressed in human gastric cancer cell lines compared to that in a normal human gastric epithelial cell line. Silencing of UPK3A inhibited the proliferation, migration, and invasion of gastric cancer cells. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis revealed that UPK3A was involved in the p53 signaling pathway. UPK3A suppressed the activation of p53 signaling pathway, and treatment with Pifithrin-α (an inhibitor of the p53 signaling pathway) or silencing of p53 significantly reversed the effect of UPK3A silencing on the expression of p53, KLF4, ZMAT3, MDM2, and SP1.

Conclusion

Our findings showed that UPK3A promotes the progression of gastric cancer by regulating the p53 signaling pathway and could be a potential therapeutic target for gastric cancer.

Evaluation of serum tRF-23-Q99P9P9NDD as a potential biomarker for the clinical diagnosis of gastric cancer

Background

Gastric cancer (GC) is one of the diseases that endanger human health with high morbidity and mortality. The positive rates of traditional biomarkers in the diagnosis of GC are low, so it is necessary to find biomarkers with high sensitivity to increase the detection rate. tRNA-derived small RNAs (tsRNAs) are novel small non-coding RNAs with specific biological functions and aberrant expression in cancer. In this study, we focused on the potential of tRNA-derived small RNAs as GC biomarkers.

Methods

The differentially expressed tsRNAs in three pairs of GC tissues were screened with high-throughput sequencing and verified using the TCGA database and Quantitative real-time PCR. The methodological evaluation of tRF-23-Q99P9P9NDD was verified by agarose gel electrophoresis, RIN evaluation, and Sanger sequencing. The Chi-square test was used to evaluate the relationship between the tRF-23-Q99P9P9NDD expression and clinicopathological parameters. Kaplan–Meier survival analysis was used to evaluate the effect of the tRF-23-Q99P9P9NDD expression on survival. Additionally, the receiver operating characteristic curve (ROC) was used to evaluate the diagnostic efficacy of tRF-23-Q99P9P9NDD in GC.

Results

Differential expression of serum tRF-23-Q99P9P9NDD could distinguish GC patients from gastritis patients and healthy donors. Chi-square test showed that high expression of tRF-23-Q99P9P9NDD was significantly associated with T stage, lymph node metastasis, TNM stage, and nerve/vascular invasion. Kaplan–Meier curve showed that patients with high expression of tRF-23-Q99P9P9NDD had a lower survival rate than patients with low expression of this biomarker. ROC analysis showed that, compared with conventional biomarkers, the efficacy of tRF-23-Q99P9P9NDD was higher, which was improved by the combination of biomarkers, and even in the early stages. Finally, we preliminarily predicted the downstream of tRF-23-Q99P9P9NDD in GC cells.

Conclusions

The expression of tRF-23-Q99P9P9NDD in GC serum can identify GC patients, and it has higher efficacy than conventional biomarkers even in the early stages. Furthermore, tRF-23-Q99P9P9NDD can monitor the postoperative conditions of GC patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s10020-022-00491-8.

Long Noncoding RNA LOC550643 Acts as an Oncogene in the Growth Regulation of Colorectal Cancer Cells

Long noncoding RNAs play a key role in the progression of colorectal cancer (CRC). However, the role and mechanism of LOC550643 in CRC cell growth and metastasis remain largely unknown. In this study, we assessed the clinical impacts of LOC550643 on CRC through the analysis of The Cancer Genome Atlas database, which revealed the significant upregulation of LOC550643 in CRC. Moreover, the high expression of LOC550643 was associated with poor survival in patients with CRC (p = 0.001). Multivariate Cox regression analysis indicated that LOC550643 overexpression was an independent prognostic factor for shorter overall survival in patients with CRC (adjusted hazard ratio, 1.90; 95% confidence interval, 1.21-3.00; p = 0.006). A biological function analysis revealed that LOC550643 knockdown reduced colon cancer cell growth by hindering cell cycle progression. In addition, LOC550643 knockdown significantly induced cell apoptosis through the inhibition of signaling activity in phosphoinositide 3-kinases. Moreover, LOC550643 knockdown contributed to the inhibition of migration and invasion ability in colon cancer cells. Furthermore, miR-29b-2-5p interacted with the LOC550643 sequence. Ectopic miR-29b-2-5p significantly suppressed colon cancer cell growth and motility and induced cell apoptosis. Our findings suggest that, LOC550643-miR-29b-2-5p axis was determined to participate in the growth and metastasis of colon cancer cells; this could serve as a useful molecular biomarker for cancer diagnosis and as a potential therapeutic target for CRC.

Novel evidence for m6A methylation regulators as prognostic biomarkers and FTO as a potential therapeutic target in gastric cancer

BACKGROUND

While emerging evidence indicates that N⁶-methyladenosine (m⁶A) regulators play crucial roles in cancer progression, their clinical significance in gastric cancer (GC) has thus far not been elucidated.

METHODS

We investigated the expression of the m⁶A regulator genes and their prognostic potential in a large clinical cohort of 173 GC patients using qRT-PCR assays. In addition, we undertook a series of in-vitro and in-vivo functional studies to investigate the oncogenic role of FTO.

RESULTS

GC patients with low expression of METTL3, METTL14, ALKBH5, WTAP and YTHDF1 demonstrated significantly poor OS, while patients with high FTO expression exhibited markedly worse OS. Furthermore, the cumulative risk-score derived from these gene panel also significantly associated with poor OS, with a corresponding hazard ratio of 5.47 (95% CI: 3.18-9.41, p < 0.0001). We observed that FTO expression was frequently upregulated in GC cell lines, with epithelial-mesenchymal-transition (EMT) features. FTO knockdown in HGC27 and AGS cells inhibited cell proliferation and migratory potential, while its overexpression in MKN28 cells resulted in enhanced proliferation and migration. Finally, confirming our in-vitro findings, FTO suppression led to significant tumour growth inhibition in a HGC27 xenograft model.

CONCLUSIONS

We demonstrate that m⁶A regulators may serve as promising prognostic biomarkers in GC. Our functional studies reveal that FTO is an important oncogene and may be a promising therapeutic target associated with EMT-alterations in gastric cancer.

Downregulation of circ-SFMBT2 blocks the development of gastric cancer by targeting the miR-885-3p/CHD7 pathway

Accumulating evidence insists that circular RNAs (circRNAs) play important roles in the development of human cancers, including gastric cancer. This study aimed to investigate the role of circ-SFMBT2 and provide a potential mechanism to explain its function. The expression of circ-SFMBT2, miR-885-3p and chromodomain-helicase-DNA-binding protein 7 (CHD7) mRNA was determined by quantitative real-time PCR (qRT-PCR), and the protein level of CHD7 was determined by western blot. To investigate the function of circ-SFMBT2 in vitro, the effects of circ-SFMBT2 on cell viability, colony formation, apoptosis, migration and invasion were assessed using cell counting kit-8 assay, colony formation assay, flow cytometry assay, wounding healing assay and transwell assay, respectively. The indicators of oxidative stress were assessed using matched kits. Besides, the function of circ-SFMBT2 was also investigated in animal models. The relationship between miR-885-3p and circ-SFMBT2 or CHD7 was verified by dual-luciferase reporter assay and RNA immunoprecipitation assay. Circ-SFMBT2 and CHD7 were upregulated, whereas miR-885-3p was downregulated in gastric cancer tissues and cells. In functional assay, circ-SFMBT2 knockdown suppressed gastric cancer cell viability, colony formation ability, migration, invasion and oxidative stress but induced apoptosis, and circ-SFMBT2 downregulation also blocked tumor growth in vivo. In mechanism analysis, circ-SFMBT2 regulated CHD7 expression by sponging its target miRNA, miR-885-3p. Rescue experiments manifested that miR-885-3p inhibition reversed the effects of circ-SFMBT2 knockdown, and CHD7 overexpression abolished the antitumor role of miR-885-3p overexpression. Moreover, circ-SFMBT2 knockdown inactivated the Wnt/β-catenin signaling pathway. Circ-SFMBT2 downregulation repressed the development of gastric cancer partially by controlling the miR-885-3p/CHD7 axis, which might be a novel strategy to inhibit gastric cancer progression.

Comprehensive analysis of prognostic genes in gastric cancer

Background: Gastric cancer is associated with high mortality, and effective methods for predicting prognosis are lacking. We aimed to identify potential prognostic markers associated with the development of gastric cancer through bioinformatic analyses.

Methods: Gastric cancer-associated gene expression profiles were obtained from The Cancer Genome Atlas and Gene Expression Omnibus databases. The key genes involved in the development of gastric cancer were obtained by differential expression analysis, coexpression analysis, and short time-series expression miner (STEM) analysis. The potential prognostic value of differentially expressed genes was further evaluated using a Cox regression model and risk scores. Hierarchical clustering was applied to validate the impact of key genes on the overall survival of gastric cancer patients.

Results: A total of 1381 genes were consistently dysregulated in the development of gastric cancer. Among them, 186 genes affected the overall survival of gastric cancer patients. The following genes had areas under the receiver operating characteristic curve greater than 0.9 in both datasets and were therefore considered key genes: ADAM12, CEP55, LRFN4, INHBA, ADH1B, DPT, FAM107A, and LOC100506388. LRFN4, DPT, and LOC100506388 were identified as potential prognostic genes for gastric cancer through a nomogram. Overexpression of LRFN4 and LOC100506388 was associated with a higher risk of gastric cancer. Finally, we found that tumors were infiltrated with high levels of Th2 cells and mast cells, and the infiltration levels were associated with overall survival in gastric cancer patients.

Conclusions: We found that key dysregulated genes may have a prognostic value for the development of gastric cancer.

Knockdown of miR-125b-5p inhibits the proliferation and invasion of gastric carcinoma cells by targeting RYBP

Gastric carcinoma, one of the most aggressive and lethal human malignancies, is associated with poor prognosis despite progress in therapeutic strategies. This study examined the potential function and mechanism of action of microRNA-125b-5p (miR-125b-5p) in the pathogenesis of gastric carcinoma. We recognized that miR-125b-5p was elevated in gastric carcinoma, and its decreased expression was associated with a better prognosis. Loss-of-function assays showed that miR-125b-5p suppression inhibited the proliferative and invasive abilities of gastric cancer cells. Furthermore, RING1 and YY1-binding protein (RYBP) was found to be target gene for miR-125b-5p action; miR-125b-5p negatively regulates RYBP expression. According to the results of rescue experiments, RYBP downregulation partially counteracted the miR-125b-5p silence-mediated inhibitory function in gastric cancer progression. Collectively, these data elucidated the molecular mechanisms of the miR-125b-5p/RYBP axis in gastric cancer invasion and growth.

Immune-Related Nine-MicroRNA Signature for Predicting the Prognosis of Gastric Cancer

Recent findings have demonstrated the superiority and utility of microRNAs (miRNAs) as new biomarkers for cancer diagnosis, therapy, and prognosis. In this study, to explore the prognostic value of immune-related miRNAs in gastric cancer (GC), we analyzed the miRNA-expression profiles of 389 patients with GC, using data deposited in The Cancer Genome Atlas database. Using a forward- and backward-variable selection and multivariate Cox regression analyses model, we identified a nine-miRNA signature (the “ImmiRSig,” consisting of miR-125b-5p, miR-99a-3p, miR-145-3p, miR-328-3p, miR-133a-5p, miR-1292-5p, miR-675-3p, miR-92b-5p, and miR-942-3p) in the training cohort that enabled the division of patients into high- and low-risk groups with significantly different survival rates. The ImmiRSig was successfully validated with an independent test cohort of 193 GC patients. Univariate and multivariate Cox regression analyses indicated that the ImmiRSig would serve as an independent prognostic factor after adjusting for other clinical covariates. Pending further prospective validation, the identified ImmiRSig appears to have significant clinical importance in terms of improving outcome predictions and guiding personalized treatment for patients with GC. Finally, significant associations between the ImmiRSig and the half-maximal inhibitory concentrations of chemotherapeutic agents were observed, suggesting that ImmiRSig may predict the clinical efficacy of chemotherapy.

Identifying Circulating MicroRNA in Kawasaki Disease by Next-Generation Sequencing Approach

Kawasaki disease (KD) typically occurs in children aged under 5 years and can cause coronary artery lesions (CALs). Early diagnosis and treatment with intravenous immunoglobulin can reduce the occurrence of CALs; therefore, identifying a good biomarker for diagnosing KD is essential. Here, using next-generation sequencing in patients with recurrent KD, those with viral infection, and healthy controls, we identified dysregulated circulating microRNAs as diagnostic biomarkers for KD. Pathway enrichment analysis illustrated the putative role of these miRNAs in KD progression. Their expression levels were validated using real-time polymerase chain reaction (qPCR). Fifteen dysregulated circulating miRNAs (fold changes >2 and <0.5) were differentially expressed in the recurrent KD group compared with the viral infection and control groups. These miRNAs were significantly involved in the transforming growth factor-β, epithelial-mesenchymal transition, and cell apoptosis signaling pathways. Notably, their expression levels were frequently restored after intravenous immunoglobulin treatment. Among the candidates, miR-24-3p expression level was significantly higher in patients with recurrent KD compared with healthy controls or viral infection controls (p < 0.001). Receiver operating characteristic analysis revealed that high miR-24-3p expression levels may be a potential biomarker for KD diagnosis. In conclusion, we identified miR-24-3p significantly higher in KD patients, which may be a potential diagnostic biomarker for KD.

Identification of Early Diagnostic and Prognostic Biomarkers via WGCNA in Stomach Adenocarcinoma

Stomach adenocarcinoma (STAD) is a leading cause of cancer deaths, and the outcome of the patients remains dismal for the lack of effective biomarkers of early detection. Recent studies have elucidated the landscape of genomic alterations of gastric cancer and reveal some biomarkers of advanced-stage gastric cancer, however, information about early-stage biomarkers is limited. Here, we adopt Weighted Gene Co-expression Network Analysis (WGCNA) to screen potential biomarkers for early-stage STAD using RNA-Seq and clinical data from TCGA database. We find six gene clusters (or modules) are significantly correlated with the stage-I STADs. Among these, five hub genes, i.e., MS4A1, THBS2, VCAN, PDGFRB, and KCNA3 are identified and significantly de-regulated in the stage-I STADs compared with the normal stomach gland tissues, which suggests they can serve as potential early diagnostic biomarkers. Moreover, we show that high expression of VCAN and PDGFRB is associated with poor prognosis of STAD. VCAN encodes a large chondroitin sulfate proteoglycan that is the main component of the extracellular matrix, and PDGFRB encodes a cell surface tyrosine kinase receptor for members of the platelet-derived growth factor (PDGF) family. Consistently, Gene Ontology (GO) analysis of differentially expressed genes in the STADs indicates terms associated with extracellular matrix and receptor ligand activity are significantly enriched. Protein-protein network interaction analysis (PPI) and Gene Set Enrichment Analysis (GSEA) further support the core role of VCAN and PDGFRB in the tumorigenesis. Collectively, our study identifies the potential biomarkers for early detection and prognosis of STAD.

Estrogen-related receptor-gamma influences Helicobacter pylori infection by regulating TFF1 in gastric cancer

Helicobacter pylori infection is a crucial factor in the development of gastric cancer (GC). Molecular therapeutic targets and mechanisms contributing to H. pylori infection-associated GC induction are poorly understood and this study aimed to fill that research gap. We found that the nuclear receptor estrogen-related receptor gamma (ESRRG) is a candidate factor influencing H. pylori infection-driven GC. ESRRG suppressed H. pylori infection and cell growth induced by H. pylori infection in GC cells and organoid models In addition, H. pylori infection downregulates ESRRG expression. Gene expression profiling revealed that trefoil factor 1 (TFF1), a well-known tumor suppressor in GC, is a downstream target of ESRRG. Mechanistically, ESRRG directly binds to the TFF1 promoter and induces TFF1 gene expression. Furthermore, TFF1 activation by ESRRG was inhibited by nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB)/p65, which is induced by inflammation, such as by H. pylori infection. Our current study provides new molecular insights into how ESRRG regulates H. pylori infection, contributing to GC development. We suggest that modulation of ESRRG-suppressing H. pylori infection could be a therapeutic target for the treatment of GC patients.

Treatment Strategies of Gastric Cancer-Molecular Targets for Anti-angiogenic Therapy: a State-of-the-art Review

Purpose

Recent studies have suggested that molecular targets for the anti-angiogenic therapy might constitute a basis for additional therapy in gastric cancer treatment. A vast number of molecules, receptors, pathways, specific interactions, and thus strategies that target gastric cancer angiogenesis specifically have been reported in numerous research articles and clinical trials.

Methods

We conducted a systematic literature review of molecularly targeted treatment strategies in gastric cancer on the following databases—PubMed, Google Scholar, and Scopus—on September 20, 2020. Multiple articles and evaluations were searched for studies reporting newly found and promising molecular anti-angiogenic therapy pathways. Eventually, 39 articles regarding the anti-angiogenic therapy in gastric cancer were included in the final analysis.

Results

As a consequence of the release of the pro-angiogenic molecules from the tumour cells, gastric cancer presents high angiogenic capability. Therefore, potential schemes for future treatment strategies include the decrease of the process ligands as well as the expression of their receptors. Moreover, the increase in the angiogenic inhibitor levels and direct aim for the inner walls of the endothelial cells appear as a promising therapeutic strategy. Beyond that, angiogenesis process inhibition seems to indirectly exaggerate the effects of chemotherapy in the considered patients.

Conclusions

The anti-angiogenic treatment in gastric cancer patients evaluates its significance especially in the early stages of the malignancy. The studies conducted so far show that most of the meaningful angiogenic factors and receptors with the potential molecular pathways should be further evaluated since they could potentially play a substantial role in future therapies.

microRNAs Mediated Regulation of the Ribosomal Proteins and its Consequences on the Global Translation of Proteins

Ribosomal proteins (RPs) are mostly derived from the energy-consuming enzyme families such as ATP-dependent RNA helicases, AAA-ATPases, GTPases and kinases, and are important structural components of the ribosome, which is a supramolecular ribonucleoprotein complex, composed of Ribosomal RNA (rRNA) and RPs, coordinates the translation and synthesis of proteins with the help of transfer RNA (tRNA) and other factors. Not all RPs are indispensable; in other words, the ribosome could be functional and could continue the translation of proteins instead of lacking in some of the RPs. However, the lack of many RPs could result in severe defects in the biogenesis of ribosomes, which could directly influence the overall translation processes and global expression of the proteins leading to the emergence of different diseases including cancer. While microRNAs (miRNAs) are small non-coding RNAs and one of the potent regulators of the post-transcriptional gene expression, miRNAs regulate gene expression by targeting the 3' untranslated region and/or coding region of the messenger RNAs (mRNAs), and by interacting with the 5' untranslated region, and eventually finetune the expression of approximately one-third of all mammalian genes. Herein, we highlighted the significance of miRNAs mediated regulation of RPs coding mRNAs in the global protein translation.

Rola miRNA w rozwoju wybranych nowotworów – potencjalne zastosowanie w diagnostyce*

MikroRNA (miRNA) są małymi cząsteczkami kwasu rybonukleinowego, które mimo że nie podlegają procesowi translacji, pełnią ważną funkcję regulacyjną w komórkach eukariotycznych. Ich fizjologiczną funkcją jest utrzymywanie homeostazy komórek. Zaburzona ekspresja miRNA może spowodować rozwój wielu chorób, w tym chorób nowotworowych. Działanie miRNA polega na hamowaniu tworzenia się białek, w tym białek o właściwościach onkogennych i antyonkogennych. Mutacje w miejscach kodowania miRNA mogą prowadzić do nadmiernego lub zmniejszonego wytwarzania wspomnianych białek. Odkrycie miRNA i poznanie ich roli w komórce otworzyło nowe możliwości dla diagnostyki chorób nowotworowych. Zmiany poziomu odpowiednich miRNA, w krwiobiegu lub innych płynach ustrojowych, mogą być markerem diagnostycznym chorób. Diagnostyka onkologiczna mogłaby przebiegać na podstawie badań profilu miRNA pacjenta i porównania go z opracowanymi wcześniej profilami zmian miRNA powiązanymi z występowaniem danego rodzaju choroby nowotworowej. Informacja o zmianach profilu miRNA podstawowych w regulacji ekspresji genów związanych z procesami nowotworzenia, mogłaby się przyczynić do opracowania terapii eksperymentalnych opartych na przywróceniu pierwotnego poziomu miRNA w komórkach, a tym samym, na przywróceniu prawidłowej regulacji ekspresji genów. Coraz nowsze metody wyciszania i włączania ekspresji miRNA mogą w przyszłości zaowocować skutecznymi rozwiązaniami terapeutycznymi.

TGFB1 polymorphisms and TGF-β1 plasma levels identify gastric adenocarcinoma patients with lower survival rate and disseminated disease

TGF‐β1 is involved in tumour growth. Four TGFB1 SNPs and TGF‐β1 production by stimulated PBMC were determined in seventy‐eight gastric adenocarcinoma patients. In addition, TGF‐β1 levels were measured in the plasma of further thirty patients. rs1800471‐G/C genotype was prevalent in patients (20.7%) compared to controls (8.4%), as it also was the rs1800468 SNP‐G/A genotype in stage IV patients (20.7%) compared to stage I, II and III patients, combined (10.3%). Conversely, the T/T rs1800469 SNP‐T/T genotype was absent in the former group and present in 19.0% in the latter. Furthermore, the rs1800469‐C/rs1800470‐T (CT) haplotype was found in 15.0% of stage IV patients as compared to 3.0% of the remaining patients (3.0%) and also identifies patients with worse five‐year life expectancy (P = .03). TGF‐β1 synthesis by stimulated PBMCs was significantly lower in patients with the risk SNPs or haplotype, compared to the alternative genotype. Finally, TGF‐β1 plasma levels were lower in patients with worse life expectancy. Analysis of TGFB1 SNPs and measurement of plasma TGF‐β1 levels serves to identify patients at risk of developing a more aggressive disease.

[Single nucleotide polymorphism of rs28416520 in Piwil1 gene promoter region is associated with an increased risk of gastric cancer]

OBJECTIVE

To analyze the correlation between the single nucleotide polymorphisms (SNPs) in the promoter of Piwil1 gene and gastric cancer.

METHODS

The expression of Piwil1 mRNA in the tumor tissues of 3 patients with gastric cancer was detected by RT-qPCR, and RNA-Sequencing data from the Cancer RNA-Seq Nexus were analyzed for Piwil1 mRNA expression in gastric patients. Blood samples were collected from 24 gastric cancer patients and 29 healthy control subjects for PCR amplification of Piwil1 gene promoter region. The SNP loci in the promoter region of Piwil1 gene were determined by direct sequencing, and the results were analyzed by SnapGene software.

RESULTS

Analysis of the data from Cancer RNA-Seq Nexus and the results of RT-qPCR in 3 gastric cancer patients all showed significantly increased Piwil1 expression in gastric cancer tissues compared with the adjacent tissues. Seven SNP loci in two CpG regions of the Piwil1 gene promoter were genotyped, and only one SNP locus was found to be related to gastric cancer. The frequencies of GG, GA, and AA genotypes at the rs28416520 locus in CpG 67 region were 79.2%, 16.7%, and 4.1% in the gastric cancer group, and were 37.9%, 55.2%, and 6.9% in the control group, respectively, showing a significantly higher frequency of the GG genotype in gastric cancer group (OR=0.144, 95%CI: 0.045-0.564, χ²=9.071, P < 0.01). The frequency of allele G of the rs28416520 locus was significantly higher in gastric cancer group than in the control group (87.5% vs 65.5%; OR=0.271, 95%CI: 0.099-0.766, χ²=6.856, P < 0.01). The genotype or allele frequencies of the other 6 SNPs locus did not differ significantly between gastric cancer group and control group.

CONCLUSIONS

The expression of Piwil1 is increased in gastric cancer tissues as compared with the adjacent tissues. The GG genotype and G allele of rs28416520 within CpG 67 region are associated with an increased risk of gastric cancer.

Development and validation of metabolism-related gene signature in prognostic prediction of gastric cancer

Gastric cancer is one of the most common malignant tumours in the world. As one of the crucial hallmarks of cancer reprogramming of metabolism and the relevant researches have a promising application in the diagnosis treatment and prognostic prediction of malignant tumours. This study aims to identify a group of metabolism-related genes to construct a prediction model for the prognosis of gastric cancer.

A large cohort of gastric cancer cases (1121 cases) from public database was included in our analysis and classified patients into training and testing cohorts at a ratio of 7: 3. After identifying a list of metabolism-related genes having prognostic value, we constructed a risk score based on metabolism-related genes using LASSO-COX method. According to the risk score, patients were divided into high- and low-risk groups. Our results revealed that high-risk patients had a significantly worse prognosis than low-risk patients in both the training (high-risk vs low-risk patients; five years overall survival: 37.2% vs 72.2%; p < 0.001) and testing cohorts (high-risk vs low-risk patients; five years overall survival: 42.9% vs 62.9%; p < 0.001). This observation was validated in the external validation cohort (high-risk vs. low-risk patients; five years overall survival: 30.2% vs 40.4%; p = 0.007).

To reinforce the predictive ability of the model, we integrated risk score, age, adjuvant chemotherapy, and TNM stage into a nomogram. According to the result of receiver operating characteristic curves and decision curves analysis, we found that the nomogram score had a superior predictive ability than conventional factors, indicating that the risk score combined with clinicopathological features can develop a robust prediction for survival and improve the individualized clinical decision making of the patient.

In conclusion, we identified a list of metabolic genes related to survival and developed a metabolism-based predictive model for gastric cancer. Through a series of bioinformatics and statistical analyses, the predictive ability of the model was confirmed.

Top-ranked expressed gene transcripts of human protein-coding genes investigated with GTEx dataset

With considerable accumulation of RNA-Seq transcriptome data, we have extended our understanding about protein-coding gene transcript compositions. However, alternatively compounded patterns of human protein-coding gene transcripts would complicate gene expression data processing and interpretation. It is essential to exhaustively interrogate complex mRNA isoforms of protein-coding genes with an unified data resource. In order to investigate representative mRNA transcript isoforms to be utilized as transcriptome analysis references, we utilized GTEx data to establish a top-ranked transcript isoform expression data resource for human protein-coding genes. Distinctive tissue specific expression profiles and modulations could be observed for individual top-ranked transcripts of protein-coding genes. Protein-coding transcripts or genes do occupy much higher expression fraction in transcriptome data. In addition, top-ranked transcripts are the dominantly expressed ones in various normal tissues. Intriguingly, some of the top-ranked transcripts are noncoding splicing isoforms, which imply diverse gene regulation mechanisms. Comprehensive investigation on the tissue expression patterns of top-ranked transcript isoforms is crucial. Thus, we established a web tool to examine top-ranked transcript isoforms in various human normal tissue types, which provides concise transcript information and easy-to-use graphical user interfaces. Investigation of top-ranked transcript isoforms would contribute understanding on the functional significance of distinctive alternatively spliced transcript isoforms.

Comparison of visceral fat area measured by CT and bioelectrical impedance analysis in Chinese patients with gastric cancer: a cross-sectional study

OBJECTIVES

Bioelectrical impedance analysis (BIA) is a simple and inexpensive method to estimate body composition. However, the accuracy of BIA is unknown. We aimed to assess the accuracy of BIA in estimating visceral fat area (VFA) in patients with gastric cancer.

STUDY DESIGN

This was a cross-sectional study comparing the accuracy of BIA in estimating VFA with the gold standard method measured by CT. VFA was measured in enrolled patients both by CT and BIA. VFA by CT at umbilical level ≥100 cm² was considered as visceral obesity. Reliability between the two methods was assessed by intraclass correlation coefficient (ICC) and consistency was assessed by Bland-Altman method (95% limits of agreement). The area under the receiver operating characteristic curve (AUROC) was used to assess the performance of BIA in diagnosing visceral obesity.

SETTING

The study was conducted in China.

PARTICIPANTS

From 1 January 2017 to 1 December 2018, a total of 157 patients diagnosed with gastric cancer were enrolled.

RESULTS

Overall, VFA by CT and BIA in patients was 84.39±46.43 cm² and 71.94±22.44 cm², respectively. VFA estimated by BIA was positively correlated with VFA measured by CT using Pearson's test (r=0.650, p<0.001). Overall, ICC for the two methods was 0.675. The mean bias between the two measurements was 12.45±36.13 cm². The 95% limits of agreement ranged from -58.36 cm² to 83.26 cm². The cut-off value for diagnosing visceral obesity by BIA was 81 cm² (AUROC: 0.822, p<0.001, 95% CI 0.758 to 0.887).

CONCLUSIONS

VFA measured by BIA showed satisfactory reliability with that measured by CT. However, the absolute values of the two methods were not interchangeable. The cut-off value for VFA by BIA in diagnosing visceral obesity was 81 cm² for patients with gastric cancer in the Chinese population.

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.

LncRNA NORAD accelerates the progression and doxorubicin resistance of neuroblastoma through up-regulating HDAC8 via sponging miR-144-3p

The dysregulation of non-coding RNAs (ncRNAs) often caused aberrant cell behaviors. In the present study, we focused on the role of long noncoding RNA (lncRNA) non-coding RNA activated by DNA damage (NORAD) in the development of neuroblastoma (NB). The enrichment of NORAD, miRNA-144-3p (miR-144-3p) and histone deacetylase 8 (HDAC8) was measured by quantitative real time polymerase chain reaction (qRT-PCR). The proliferation, chemoresistance, apoptosis, metastasis and autophagy of NB cells were determined by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), flow cytometry, transwell migration and invasion assays and Western blot assay, respectively. The target relationship between miR-144-3p and NORAD or HDAC8 was predicted by Starbase software and validated through dual-luciferase reporter assay, RIP and RNA-pull down assays. The protein expression of HDAC8 was measured by Western blot assay. Murine xenograft model was used to verify the function of NORAD in vivo. We found that the level of NORAD was up-regulated in NB tissues and cells, and the level of NORAD was negatively correlated with the prognosis of NB patients. NORAD promoted the proliferation, metastasis and doxorubicin (DOX) resistance while inhibited the apoptosis and autophagy of NB cells. MiR-144-3p was a target of NORAD in NB cells, and NORAD accelerated the progression and DOX resistance of NB through sponging miR-144-3p. HDAC8 was a direct target of miR-144-3p in NB cells, and miR-144-3p suppressed the progression of NB through down-regulating HDAC8. NORAD up-regulated the expression of HDAC8 through sponging miR-144-3p in NB cells. NORAD accelerated the growth of NB tumors at least partly through miR-144-3p/HDAC8 signaling in vivo. In conclusion, NORAD promoted the progression and DOX resistance of NB through miR-144-3p/HDAC8 axis in vivo and in vitro.

Evaluating the diagnostic and prognostic value of serum long non-coding RNA CTC-497E21.4 in gastric cancer

Background Long non-coding RNAs (lncRNAs) have been reported to play a key role in gastric cancer (GC) tumorigenesis. However, the clinical application value of serum lncRNAs in GC has remained largely unknown. We investigated the role of a novel lncRNA named CTC-497E21.4 in the diagnosis and the prognosis of GC. Methods We focused on evaluation of lncRNA CTC-497E21.4 by real-time fluorescent quantitative polymerase chain reaction (RTFQ-PCR). The study involved following aspects: (1) confirmation of the higher lncRNA CTC-497E21.4 expression in different types of GC specimens than corresponding controls; (2) evaluation of monitoring tumor dynamics by the serum lncRNA CTC-497E21.4 assay; (3) evaluation of the prognostic value of lncRNA CTC-497E21.4 assay in GC. Results (1) The method of RTFQ-PCR detection of lncRNA CTC-497E21.4 was evaluated to have high sensitivity and specificity. (2) The expression levels of lncRNA CTC-497E21.4 were higher in GC patients compared with corresponding controls (p<0.001), and the combination of serum lncRNA CTC-497E21.4, CEA and CA19-9 could improve diagnostic sensitivity (96.36%). (3) The serum lncRNA CTC-497E21.4 expression levels were lower in postoperative samples than preoperative samples (p=0.0021) and survival curves downloaded from TCGA showed high lncRNA CTC-497E21.4 levels were associated with poor OS of GC (p=0.0351). Conclusions lncRNA CTC-497E21.4 may be a potential biomarker for the diagnosis and the prognosis of GC.

[miR-449a/b negatively regulates E2F1 to suppress proliferation of gastric cancer cells]

OBJECTIVE

To investigate the possible role of miR-449a/b in the occurrence of gastric cancer.

METHODS

The expression of miR-449a/b and E2F1 mRNA in gastric cancer cells BGC-823 and gastric mucosal cells GES-1 were detected with qRT-PCR. miR-449a/b mimics or a negative control was transiently transfected into BGC-823 cells, and the changes in cell proliferation, apoptosis, and migration ability were assessed using CCK-8 assay, flow cytometry, and scratch wound healing assay, respectively. Western blotting was used to observe the effects of miR-449a/b upregulation on its target gene expression. The effects of transfection with an E2F1-over-expressing plasmid or an empty plasmid were analyzed on the expression level of miR-449a/b in BGC-823 cells using qRT-PCR and digital PCR.

RESULTS

The gastric cancer cell line BGC-823 showed significantly a lowered expression of miR-449a/b compared with the normal gastric mucosal cell line GES-1 (P < 0.01). Overexpression of miR-449a/b obviously inhibited the proliferation and migration and promoted apoptosis of BGC-823 cells (P < 0.05). Overexpression E2F1 in the cells resulted in significantly up-regulated expression of miR-449a/b (P < 0.001). Upregulation of miR-449a/b caused significant down-regulation of its direct target genes CDK4 and CDK6 and also of the expression of E2F1 protein via the CDKs-pRb-E2F1 signaling pathway.

CONCLUSIONS

The low expression of miR-449a/b and the high expression of E2F1 are both involved in the occurrence and progression of gastric cancer, and miR-449a/b negatively regulates E2F1 to inhibit the proliferation of gastric cancer cells.

TRIM32 Promotes the Growth of Gastric Cancer Cells through Enhancing AKT Activity and Glucose Transportation

Tripartite motif protein 32 (TRIM32), an E3 ubiquitin ligase, is a member of the TRIM protein family. However, the underlying function of TRIM32 in gastric cancer (GC) remains unclear. Here, we aimed to explore the function of TRIM32 in GC cells. TRIM32 was induced silencing and overexpression using RNA interference (RNAi) and lentiviral-mediate vector in GC cells, respectively. Moreover, the PI3K/AKT inhibitor LY294002 was used to examine the relationship between TRIM32 and AKT. Quantitative reverse-transcription PCR (qRT-PCR) and western blot were used to determine the mRNA and protein contents. The glucose analog 2-NBDG was used as a fluorescent probe for determining the activity of glucose transport. An annexin V-fluorescein isothiocyanate apoptosis detection kit was used to stain NCI-N87, MKN74, and MKN45 cells. Cell counting kit-8 (CCK-8) assay was used to examine cell proliferation. Our results indicated that TRIM32 was associated with poor overall survival of patients with GC. Moreover, TRIM32 was a proproliferation and antiapoptosis factor and involved in the AKT pathway in GC cells. Furthermore, TRIM32 possibly mediated the metabolism of glycolysis through targeting GLUT1 and HKII in GC cells. Importantly, TRIM32 silencing deeply suppressed the tumorigenicity of GC cells in vivo. Our findings not only enhanced the understanding of the function of TRIM32 but also indicated its potential value as a target in GC treatment.

miR-629 targets FOXO3 to promote cell apoptosis in gastric cancer

Gastric cancer (GC) is one of the most aggressive types of human tumor worldwide, and the 5-year survival rate is less than 25%. The transcriptional factor, forkhead box O3 (FOXO3), is regulated by various micro (mi)RNAs and has been reported to be associated with multiple regulatory signaling pathways involved in tumor development. The current study therefore assessed the impact of miR-629 and FOXO3 on gastric cancer. Reverse transcription-quantitative polymerase chain reaction and western blotting were performed to assess the expression of mRNA and protein, respectively. Additionally, the cell proliferation and apoptosis rate were determined via an MTT assay and flow cytometry, respectively. The online database TargetScan predicted that FOXO3 was a target of miR-629. A luciferase reporter assay was also performed to verify that FOXO3 was the direct target of miR-629. The results demonstrated that miR-629 and FOXO3 was upregulated and downregulated in GC tissue, respectively. Furthermore, following transfection with a miR-629 inhibitor, SGC-7901, cell proliferation and apoptosis rate were inhibited and promoted when compared with the control group, respectively. Moreover, after the treatment with SGC-7901, the expression of FOXO3, Bax, Caspase 3 was upregulated, and Bcl-2 was downregulated. Furthermore, the luciferase reporter assay revealed that FOXO3 was the target of miR-629. The results demonstrated that miR-629 and FOXO3 serve vital roles in the development of gastric cancer and may be a future therapeutic target.

Precision medicine in gastric cancer

Gastric cancer (GC) is a complex disease linked to a series of environmental factors and unhealthy lifestyle habits, and especially to genetic alterations. GC represents the second leading cause of cancer-related deaths worldwide. Its onset is subtle, and the majority of patients are diagnosed once the cancer is already advanced. In recent years, there have been innovations in the management of advanced GC including the introduction of new classifications based on its molecular characteristics. Thanks to new technologies such as next-generation sequencing and microarray, the Cancer Genome Atlas and Asian Cancer Research Group classifications have also paved the way for precision medicine in GC, making it possible to integrate diagnostic and therapeutic methods. Among the objectives of the subdivision of GC into subtypes is to select patients in whom molecular targeted drugs can achieve the best results; many lines of research have been initiated to this end. After phase III clinical trials, trastuzumab, anti-Erb-B2 receptor tyrosine kinase 2 (commonly known as ERBB2) and ramucirumab, anti-vascular endothelial growth factor receptor 2 (commonly known as VEGFR2) monoclonal antibodies, were approved and introduced into first- and second-line therapies for patients with advanced/metastatic GC. However, the heterogeneity of this neoplasia makes the practical application of such approaches difficult. Unfortunately, scientific progress has not been matched by progress in clinical practice in terms of significant improvements in prognosis. Survival continues to be low in contrast to the reduction in deaths from many common cancers such as colorectal, lung, breast, and prostate cancers. Although several target molecules have been identified on which targeted drugs can act and novel products have been introduced into experimental therapeutic protocols, the overall approach to treating advanced stage GC has not substantially changed. Currently, surgical resection with adjuvant or neoadjuvant radiotherapy and chemotherapy are the most effective treatments for this disease. Future research should not underestimate the heterogeneity of GC when developing diagnostic and therapeutic strategies aimed toward improving patient survival.

High-Expression HBO1 Predicts Poor Prognosis in Gastric Cancer

OBJECTIVES

Our goal was to assess the expression of histone acetyltransferase binding to origin recognition complex 1 (HBO1) in gastric cancer and the effect on prognosis for the patients.

METHODS

We used quantitative reverse transcription polymerase chain reaction, Western blot, and tissue microarray immunohistochemistry to investigate the expressions of HBO1 messenger RNA (mRNA) and protein in gastric cancer tissues. Online resources, including Oncomine and Kaplan-Meier Plotter, were used to further assess the correlation between HBO1 expression and the prognosis of the patients with gastric cancer.

RESULTS

HBO1 mRNA and protein expressions in gastric cancer tissues were both significantly higher than those in normal tissues. The correlations between high HBO1 expression and differentiation, invasive depth (T), lymph node metastasis (N), distant metastasis (M), TNM staging, and serum carcinoembryonic antigen levels were positive. High HBO1 expression was negatively correlated with survival time in patients with gastric cancer.

CONCLUSIONS

HBO1 might be a valuable biomarker to evaluate the prognosis of patients with gastric cancer.

Cyr61 overexpression induced by interleukin 8 via NF-kB signaling pathway and its role in tumorigenesis of gastric carcinoma in vitro

Cyr61 (CCN1) is a multifunctional matricellular protein in bridging inflammation and cancer, involved in many biological functions such as tumorigenesis and carcinogenesis. The role of Cyr61 in gastric cancer (GC) has not been fully understood and needs to be investigated and clarified. We examined Cyr61 expression in 6 GC cell lines and stable transfection of recombinants in to BGC823 specifically down regulated the Cyr61 mRNA and protein expression shown by the analysis with western blot, RT-PCR, western blot and immunofluorescence assay. The cells treated with siRNA shown markedly reduced activity in growth, migration and invasion compared with parental BGC823 cells as well as mock transfectants. The Cyr61 deficient cells demonstrated significantly inhibited colony formation in soft agar and reduced tumorigenicity was showed in nude mice, NF-kB pathway evidently inactivated respectively. However, under the stimulation of IL-8, the siRNA-treated cells can restore the capacity of proliferation and invasion. IL-8 can induce the high expression of Cyr61 and MMP11 through NF-kB signal pathway. Silencing of Cyr61 can inhibit or minimize the proliferation and invasiveness of gastric cancer cell. The results imply that Cyr61 enhance the proliferation and invasion of gastric cancer cells and this process is partially modulated by the IL-8 up-regulation. Cyr61 may mediate the proliferation and development of gastric carcinoma.

MicroRNA-377-3p inhibits growth and invasion through sponging JAG1 in ovarian cancer

BACKGROUND

Ovarian cancer is the one of the most deadly gynecologic malignancy among cancer related death in women. However, the treatment for ovarian cancer is still limited. In this study, we aimed to explore the inhibition potential of miR-377-3p in ovarian cancer and explore the mechanism of this effect.

METHODS

Quantitative real-time PCR was used to detect the mRNA or microRNA (miRNA) levels. CCK-8, wound-healing, transwell assay were used to detect cell proliferation, migration and invasion. The protein levels were examined by western blot. The dual luciferase reporter assay was conducted to examine the luciferase activity. Tumor volume was measured and Ki67 was detected via immunohistochemistry.

RESULTS

qRT-PCR results showed that miR-377-3p was downregulated in ovarian cancer patients. MiR-377-3p mimics suppressed cell proliferation, migration, invasion and decreased the JAG1 level. However, miR-377-3p inhibitor promoted these appearances. Interestingly, we found JAG1 was a target gene of miR-377-3p. JAG1 overexpression reversed the miR-377-3p-induced inhibition of proliferation and invasion. In addition, miR-377-3p inhibited ovarian cancer tumorigenesis in vivo, indicating by decreased tumor volume and staining of Ki67.

CONCLUSION

The results showed that miR-377-3p inhibited growth and invasion of ovarian cancer cells by targeting JAG1.

Differential expression profile analysis of cisplatin‑regulated miRNAs in a human gastric cancer cell line

Cisplatin, one of the most commonly used drugs in combination chemotherapy, is an effective anti‑tumor agent widely used for diverse tumor types. MicroRNAs (miRNAs/miRs) are involved in the occurrence, development, diagnosis and treatment of cancer. Therefore, the aim of the current study was to explore whether cisplatin exerts anticancer effects by causing differential expression of miRNAs in human gastric cancer cells. The human gastric cancer cell line NCI‑N87 was cultured with a certain dose of cisplatin and high‑throughput sequencing combined with reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) was performed to detect cisplatin‑regulated miRNAs. miRNAs upregulated and downregulated following cisplatin exposure were analyzed. High‑throughput sequencing revealed 33 upregulated and 16 downregulated miRNAs. A total of five significantly upregulated and five significantly downregulated miRNAs were identified by RT‑qPCR. The expression levels of hsa‑miR‑1246 and hsa‑miR‑892b were consistent with the results obtained from high‑throughput sequencing. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway clustering of cisplatin‑regulated miRNAs revealed that the miRNAs regulated genes involved in several biological processes and signaling pathways. The results obtained in the current study suggested that cisplatin may exert an important anticancer effect in gastric cancer via complex biological processes and signaling pathways.