Correlation of CTLA-4 polymorphism and the risk of gastric cancer in a Chinese Bai population.

Cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) is involved in the regulation of immune responses mediated by T cells. This study aimed to explore the correlation between CTLA-4 gene polymorphisms and the risk of gastric cancer (GC) in the Bai minority population of southwestern China. A total of 422 GC patients and 397 healthy controls (HC) were included in this case-control study. Four single nucleotide polymorphism sites of CTLA-4 gene (rs231775, rs733618, rs16840252 and rs3087243) were selected and analysed. The results showed a significant difference in the rs733618 loci between GC and HC groups. The frequency of the rs733618 polymorphism 'TC' genotype was significantly lower in GC group compared to the HC group [odds ratio (OR), 95% confidence interval (CI): .47 (.35-.63), p < .001]. GC cases with dominant genetic model 'TC + CC' had a 47% reduced risk of GC [OR, 95%CI: .53 (.40-.71), p < .001]. Subgroup analyses revealed that the rs733618 'TC + CC' genotype was associated with a lower risk of GC in male patients [OR, 95%CI: .42 (.31-.58), p < .001], those aged ≤60 years old [OR, 95%CI: .27 (.18-.42), p < .001], non-drinkers [OR, 95%CI: .21 (.13-.33), p < .001], non-smokers [OR, 95%CI: .38 (.25-.57), p < .001] and individuals without Helicobacter pylori infection [OR, 95%CI: .16 (.10-.26), p < .001]. Further multivariated analyses indicated that individuals with the 'TC + CC' rs733618 genotype who were aged ≤60 years old [OR, 95%CI: .42 (.29-.83), p = .032] and had no H. pylori infection [OR, 95%CI: .35 (.28-.76), p = .018] were found to have a protective effect against GC. Additionally, soluble CTLA-4 were significantly lower in GC patients with 'TC' and 'TC + CC' genotypes (all p < .05). Our findings suggest that the rs733618 polymorphism of CTLA-4 gene may play a critical role in the prevention of GC.

As a biomarker for gastric cancer, circPTPN22 regulates the progression of gastric cancer through the EMT pathway.

BACKGROUND: Gastric cancer (GC) is one of the most common cancers in the world. Due to the lack of specific symptoms, more than 80% of patients are diagnosed as the advanced stage with a high mortality rate, so the early diagnosis of GC is incredibly essential. Circular RNAs (CircRNAs) are a kind of endogenous non-coding RNA with stable structure, the long half-life, and tumor specificity. It can be used as a diagnostic marker for tumors. METHOD: Using circRNA sequencing technology screened three pairs of GC and adjacent tissues, and circRNAs with significant expression differences were screened out. The circular structure and characteristics of circPTPN22 were determined by RT-qPCR, agarose gel electrophoresis, Sanger sequencing, RNase R, and actinomycin D assays. Cell Counting Kit-8, colony formation, Transwell, Wound healing, tumor formation in mice and western blotting assays were used to detect the effects of circPTPN22 on the proliferation, invasion, migration, tumor growth of GC cells in vitro and protein expression. RESULT: CircPTPN22 is up-regulated and positively correlated with metastasis in GC tissues, cells, and plasma. RT-qPCR results showed that circPTPN22 had good diagnostic efficacy and could be used to predict the prognosis of GC patients. In vitro and vivo experiments showed that the downregulation of circPTPN22 could inhibit cell proliferation, migration, and invasion through the epithelial-mesenchymal transformation (EMT) pathway. CircPTPN22 may regulate GC progression through the competitive binding of miRNAs. CONCLUSION: CircPTPN22 can be used as a potential diagnostic and prognostic marker for GC and can inhibit cell proliferation and metastasis through the competitive binding of miRNA to inhibit the EMT pathway.

High ratio of C-reactive protein/procalcitonin predicts Mycoplasma pneumoniae infection among adults hospitalized with community acquired pneumonia.

There is limited data on serum biomarkers in distinguishing Mycoplasma pneumoniae (MP) from Streptococcus pneumoniae (SP) and viral pneumoniae (VP) etiologies of community-acquired pneumonia (CAP). A retrospective study of inpatients diagnosed with CAP at the First Affiliated Hospital of Dali University (Dali, Yunnan, China) between January 2018 and June 2020 was conducted. The demographic, clinical and laboratory data of the patients with CAP were analyzed. Univariate analyses identified predictors for MP infections. The discriminative power of C-reactive protein (CRP), procalcitonin (PCT), CRP/PCT and CRP/PCT >350 µg/ng was assessed by area under the curve (AUC) of the receiver operating characteristic (ROC) curves. A total of 552 CAP patients, including 247 (44.7%) with MP, 152 (27.6%) with SP and 153 (27.7%) with influenza A and B viruses, were enrolled. When comparing MP with SP, cough and CRP/PCT >350 µg/ng (odds ratio [OR]) 2.88, p < .001) were predictors for MP. CRP/PCT >350 µg/ng had 76% sensitivity and 100% specificity (AUC = 0.89, p < .001, 95% confidence interval [CI]:0.81-0.94) to predict MP infections. Furthermore, similar results were again obtained when comparing MP with VP. CRP/PCT >350 µg/ng present better information (OR: 4.70; AUC = 0.92, p < .001, 87% sensitivity and 100% specificity). In addition, comparing MP and non-MP (SP and VP combined), CRP/PCT >350 µg/ng exhibited excellent performance (AUC = 0.90, 95%CI 0.83-0.95, p < .001, 76% sensitivity and 100% specificity). CRP/PCT ratio may be a potential index to distinguish MP-CAP from non-MP-CAP.

PCAT-1 promotes cell growth by sponging miR-129 via MAP3K7/NF-κB pathway in multiple myeloma.

Loss of one or some specific miRNA-mediated regulation is closely associated with malignant progression of multiple myeloma (MM). But how these miRNAs work and what role the specific miRNA plays in this process of malignant progression remain unclear. It was found in this study that the expression of miR-129 was decreased in both MM cell lines and newly diagnosed MM patients. Further clinicopathological statistics showed that miR-129 was correlated with the isotype of MM patients. MiR-129 overexpression disturbed cell proliferation, cell cycle evolution and spurred apoptosis both in vitro and in vivo. MAP3K7, a kinase able to activate NF-κB circuit, was found to be up-regulated in MM and contain a binding target of miR-129. In addition, lncRNA PCAT-1 functioned to sponge miR-129 and thereby lowered its expression. PCAT-1 knockdown eliminated the tumour-promoting effect caused by miR-129 inhibition, probably through repressing MAP3K7 and subsequent NF-κB activation. To the best of our knowledge, this is the first study to have discovered that increased expression of PCAT-1 could augment cell proliferation and cycle procession and inhibit apoptosis by down-regulating miR-129 via the MAP3K7/NF-κB pathway in MM.

CircRNAs: biogenesis, functions, and role in drug-resistant Tumours.

Targeted treatment, which can specifically kill tumour cells without affecting normal cells, is a new approach for tumour therapy. However, tumour cells tend to acquire resistance to targeted drugs during treatment. Circular RNAs (circRNAs) are single-stranded RNA molecules with unique structures and important functions. With the development of RNA sequencing technology, circRNAs have been found to be widespread in tumour-resistant cells and to play important regulatory roles. In this review, we present the latest advances in circRNA research and summarize the various mechanisms underlying their regulation. Moreover, we review the role of circRNAs in the chemotherapeutic resistance of tumours and explore the clinical value of circRNA regulation in treating tumour resistance.

The potential role of RNA N6-methyladenosine in Cancer progression.

N6-methyladenosine (m6A) is considered the most common, abundant, and conserved internal transcript modification, especially in eukaryotic messenger RNA (mRNA). m6A is installed by m6A methyltransferases (METTL3/14, WTAP, RBM15/15B, VIRMA and ZC3H13, termed "writers"), removed by demethylases (FTO, ALKBH5, and ALKBH3, termed "erasers"), and recognized by m6A-binding proteins (YTHDC1/2, YTHDF1/2/3, IGF2BP1/2/3, HNRNP, and eIF3, termed "readers"). Accumulating evidence suggests that m6A RNA methylation greatly impacts RNA metabolism and is involved in the pathogenesis of many kinds of diseases, including cancers. In this review, we focus on the physiological functions of m6A modification and its related regulators, as well as on the potential biological roles of these elements in human tumors.

Bioinformatics-Based Study to Investigate Potential Differentially Expressed Genes and miRNAs in Pediatric Sepsis.

BACKGROUND Sepsis is an extremely common health issue with a considerable mortality rate in children. Our understanding about the pathogenic mechanisms of sepsis is limited. The aim of this study was to identify the differential expression genes (DEGs) in pediatric sepsis through comprehensive analysis, and to provide specific insights for the clinical sepsis therapies in children. MATERIAL AND METHODS Three pediatric gene expression profiles (GSE25504, GSE26378, GSE26440) were downloaded from the Gene Expression Omnibus (GEO) database. The difference expression genes (DEGs) between pediatric sepsis and normal control group were screened with the GEO2R online tool. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses of the DEGs were performed. Cytoscape with CytoHubba were used to identify the hub genes. Finally, NetworkAnalyst was used to construct the targeted microRNAs (miRNAs) of the hub genes. RESULTS Totally, 160 overlapping upward genes and 61 downward genes were identified. In addition, 5 KEGG pathways, including hematopoietic cell lineage, Staphylococcus aureus infection, starch and sucrose metabolism, osteoclast differentiation, and tumor necrosis factor (TNF) signaling pathway, were significantly enriched using a database for labeling, visualization, and synthetic discovery. In combination with the results of the protein-protein interaction (PPI) network and CytoHubba, 9 hub genes including ITGAM, TLR8, IL1ß, MMP9, MPO, FPR2, ELANE, SPI1, and C3AR1 were selected. Combined with DEG-miRNAs visualization, 5 miRNAs, including has-miR-204-5p, has-miR-211-5p, has-miR-590-5p, and has-miR-21-5p, were predicted as possibly the key miRNAs. CONCLUSIONS Our findings will contribute to identification of potential biomarkers and novel strategies for pediatric sepsis treatment.

Pyridostigmine ameliorates cardiac remodeling induced by myocardial infarction via inhibition of the transforming growth factor-ß1/TGF-ß1-activated kinase pathway.

Autonomic imbalance characterized by sympathetic predominance coinciding with diminished vagal activity is an independent risk factor in cardiovascular diseases. Several studies show that vagus nerve stimulation exerted beneficial effects on cardiac function and survival. In this study, we investigated the vagomimetic effect of pyridostigmine on left ventricular (LV) remodeling in rats after myocardial infarction. After myocardial infarction, surviving rats were treated with or without pyridostigmine (31 mg·kg⁻¹·d⁻¹) for 2 weeks, and hemodynamic parameters were measured. LV tissue was used to assess infarct size and interstitial fibrosis by Masson's trichrome and 0.1% picrosirius red staining. Protein expression of heart tissues was used to assess the efficacy of the treatment. Pyridostigmine markedly reduced myocardial infarct size and improved cardiac diastolic function. These improvements were accompanied with a significant decrease in matrix metalloproteinase-2 expression and collagen deposition. Additionally, pyridostigmine inhibited both transforming growth factor-ß1 (TGF-ß1) and TGF-ß1-activated kinase expression in hearts postmyocardial infarction. Thus, pyridostigmine reduces collagen deposition, attenuates cardiac fibrosis, and improves LV diastolic function after myocardial infarction via TGF-ß1/TGF-ß1-activated kinase pathway inhibition.

A comprehensive evaluation of serum circCSPP1 as a novel diagnostic and prognostic biomarker for gastric cancer.

PURPOSE: Gastric cancer (GC) has high incidence and mortality due to its low early screening efficiency. Circular RNAs (CircRNAs) are a new class of non-coding RNAs which is closely related to GC. Nevertheless, the clinical application value of circRNAs in GC are largely unknown. Therefore, we studied the role of a novel circRNA named circCSPP1 in patients with GC. METHODS: CircRNA sequencing was performed to screen out the target molecule. Real-time fluorescent quantitative PCR (RT-qPCR) was utilized to detect the expression level of circCSPP1 in GC tissues, cells, and serum. Gel and Sanger sequencing were utilized to verify the ring structure of circCSPP1. RNase R enzyme digestion experiment and actinomycin D experiment were verifed the advantage of circCSPP1 as a diagnostic biomarker in patients with GC when that compared with linear RNA. The correlation between the expression level of serum circCSPP1 and clinicopathological data of GC patients was further analyzed. Receiver operating characteristic curve (ROC) and the area under ROC curve (AUC) were utilied to evaluate the diagnostic performance. RESULTS: CircCSPP1 has a circular structure which with resistance to RNA exonuclease digestion and long half-life compared with linear RNA. In our study, circCSPP1 was first found up-regulated in patients with GC. Serum circCSPP1 level was decreased significantly after surgical resection whereas increased after recurrence. High expression of circCSPP1 was associated with poor survival rates. The expression level of circCSPP1 was significantly correlated to tumor size, T stage, lymph node metastasis, and TNM stage. The AUC of serum circCSPP1 was 0.834, with high sensitivity and specificity in discriminating patients with GC from healthy donors. More importantly, the combined diagnosis of circCSPP1, CEA, and CA19-9 achieved the superior AUC of 0.882, with the highest specificity. CONCLUSION: Serum circCSPP1 may prove to be a potential non-invasive auxiliary diagnostic biomarker for patients with GC.

Circ_0004592: An auxiliary diagnostic biomarker for gastric cancer.

BACKGROUND: Gastric cancer (GC) has a high mortality rate, and robust diagnostic biomarkers are currently lacking. However, the clinical relevance of circular RNAs (circRNAs) as GC biomarkers remains largely unexplored. AIM: To evaluate the potential of novel circRNA circ_0004592 in the early screening and prognosis of GC. METHODS: High-throughput sequencing of circRNAs was performed to screen for potential target molecules. Circ_0004592 expression was examined in GC tissues, cells, and plasma. Plasma samples were collected from healthy subjects' patients, as well as from patients with benign lesions, precancerous lesions, and GC, whereafter the diagnostic accuracy of circ_0004592 was evaluated. The correlation between circ_0004592 levels in plasma and clinicopathological data of patients with GC was further analyzed. RESULTS: Circ_0004592 was upregulated in both the tissue and plasma of patients with GC. Further, circ_0004592 expression was higher in patients with precancerous lesions than in healthy controls while being highest in patients with GC. In the same patient, the postoperative plasma level of circ_0004592 was lower than that in the preoperative period. Moreover, circ_0004592 level was significantly correlated with tumor differentiation, tumor depth, and lymph node metastasis. The area under the curve (AUC) of plasma circ_0004592 exhibited high sensitivity and specificity for differentiating patients with GC from healthy donors. Diagnosis based on circ_0004592, carcinoembryonic antigen, and cancer antigen 199 achieved a superior AUC and was highly sensitive. CONCLUSION: Plasma circ_0004592 may represent a potential non-invasive auxiliary diagnostic biomarker for patients with GC.

Stop Ischemic Event to the Brain: Screening Risk Factors of Cerebrovascular Stenosis in Coronary Artery Disease Patients.

OBJECTIVES: In this study, we investigated the difference in risk factors between the 2 diseases, aiming to further clarify who needs to do ischemic cerebrovascular disease (ICVD)-related screening among coronary artery disease (CAD) patients. METHODS: Clinical data of 326 patients with first-episode CAD from June 1, 2017, to July 31, 2020, in the Chinese PLA General Hospital were retrospectively reviewed. Outcomes, including clinical features and laboratory examination, were taken. Features related to ICVD including the extension of intracranial arterial (internal carotid artery intracranial segment, middle cerebral artery M1 segment, anterior cerebral A1 segment, vertebrobasilar artery intracranial segment, posterior cerebral artery P1 segment) and carotid arterial (internal carotid artery extracranial segment, common carotid artery, subclavian artery) stenosis were detected. Risk factors for the occurrence of ICVD in patients with CAD were analyzed. RESULTS: Among patients with the onset of CAD, in comparison of the nonstenosis and stenosis of intracranial artery subgroups, there were statistical differences in the onset age, hypertension, and duration of hypertension as well as the biochemical indicators, including high-density lipoprotein and glycosylated hemoglobin. In addition, statistical differences were detected in the onset age as well as the biochemical indicators, including glycosylated hemoglobin and blood glucose serum protein, along with the difference in the degree of cardiovascular stenosis. CONCLUSIONS: The onset age of CAD was shown to serve as a vital risk factor for ICVD. The primary prevention of ICVD in patients with CAD should lay more emphasis on the management of hypertension and diabetes.

MicroRNA miR-1275 coordinately regulates AEA/LPA signals via targeting FAAH in lipid metabolism reprogramming of gastric cancer.

Glycerophospholipid signal and fatty acid metabolism are closely related to the occurrence and progression of tumours, and metabolic reprogramming caused by hydrolytic enzymes plays an important role in gastric cancer (GC). Here, we performed whole transcriptome sequencing and combined qRT-PCR to screen out the significantly high expression of fatty acid amide hydrolase (FAAH) in GC tissues, which was further verified in both TCGA and Oncomine databases. Functional tests confirmed that FAAH played an oncogene role in GC, and silencing FAAH could delay tumour growth, inhibit tumour metastasis, and promote cell apoptosis both in vitro and in vivo. FAAH-mediated lipid metabolism reprogramming through coordinated regulation of arachidonoyl ethanolamide (AEA)/lysophosphatidic acid (LPA) signalling and activated the cyclooxygenase-2 (COX-2)/prostaglandin E2 (PGE2) axis to promote GC progression. Luciferase reporter assay and immunofluorescence-fluorescence in situ hybridization (IF-FISH) were applied to validate the interactions of miR-1275/FAAH. Overexpression and knockdown of miR-1275 in vitro could indirectly modulate the above lipid signalling by targeting FAAH, thereby affecting GC progression. Our study indicates that deregulated FAAH is a key lipid signal and the miR-1275/FAAH/AEA/LPA axis can serve as a diagnostic biomarker for GC or as a target for therapy development.

Protection against ischemia-induced oxidative stress conferred by vagal stimulation in the rat heart: involvement of the AMPK-PKC pathway.

Reactive oxygen species (ROS) production is an important mechanism in myocardial ischemia and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase is one of major sources of ROS in the heart. Previous studies showed that vagus nerve stimulation (VNS) is beneficial in treating ischemic heart diseases. However, the effect of VNS on ROS production remains elusive. In this study, we investigated the role of VNS onischemia-induced ROS production. Our results demonstrated that VNS alleviated the myocardial injury, attenuated the cardiac dysfunction, reserved the antioxidant enzyme activity and inhibited the formation of ROS as evidenced by the decreased NADPH oxidase (Nox) activity and superoxide fluorescence intensity as well as the expression of p67phox, Rac1 and nitrotyrosine. Furthermore, VNS resulted in the phosphorylation and activation of adenosine monophosphate activated protein kinase (AMPK), which in turn led to an inactivation of Nox by protein kinase C (PKC); however, the phenomena were repressed by the administration of a muscarinic antagonist atropine. Taken together, these data indicate that VNS decreases ROS via AMPK-PKC-Nox pathway; this may have potential importance for the treatment of ischemic heart diseases.

Hsa_circ_0000437 promotes pathogenesis of gastric cancer and lymph node metastasis.

Cellular communication between gastric cancer (GC) cells with different metastatic potentials and microenvironments and resultant cancer progression is not fully understood. Circular RNAs (circRNAs) and exosomal circRNAs are known to play extremely important regulatory roles in GC occurrence and progression. Here, we revealed significant differences in coronin-like actin-binding protein 1C (CORO1C) derived circRNA hsa_circ_0000437 between GC and para-cancer tissues. Hsa_circ_0000437 regulated GC cell proliferation, invasion, migration and apoptosis by targeting Ser/Arg-rich splicing factor 3 (SRSF3) and inhibiting programmed cell death 4 (PDCD4). The ectopic expression of hsa_circ_0000437 dramatically promoted tumor growth in nude mice in vivo. Furthermore, both gain-of-function and loss-of-function experiments demonstrated that hsa_circ_0000437 promoted human lymphatic endothelial cells (HLECs) invasion, migration, and tube formation in vitro and also promoted lymphangiogenesis and lymph node metastasis (LNM) in popliteal LNM model in vivo, when it was enriched in GC-secreted exosomes and transferred into HLECs. Mechanistically, exosomal hsa_circ_0000437 induced LNM via HSPA2-ERK signaling pathway independent of VEGF-C. Clinical data showed that exosomal hsa_circ_0000437 was enriched in the serum of GC patients, which was associated with LNM. In summary, these findings highlight the potential role of hsa_circ_0000437 as an outcome biomarker in GC patients with LNM, which may provide a novel target for GC therapy.

Acetylcholine prevents angiotensin II-induced oxidative stress and apoptosis in H9c2 cells.

Apoptosis of cardiomyocytes plays an important role in the development of cardiovascular diseases (CVD). Numerous studies have shown that generation of reactive oxygen species (ROS) induced by the renin-angiotensin system (RAS) is involved in this pathological process. Recent studies also suggested that acetylcholine (ACh) prevented the hypoxia-induced apoptosis of mouse ES cells by inhibiting the ROS production. However, whether ACh can inhibit the action of angiotensin II (Ang II) and subsequently prevent CVD development remains unclear. In this study, H9c2 cells were stimulated by 10(-6) M Ang II for 24 h with or without 10(-5) M ACh, 10(-5) M ACh + 10(-4) M atropine respectively. The results demonstrated that Ang II increased apoptosis index by fourfold (vs. the control group, P < 0.01), which were significantly diminished by ACh. However, the atropine (ACh receptor [AChR] inhibitor) treatment blocked the protective effect of ACh. Subsequently, Ang II significantly increases the expression and activity of NADPH oxidase so that ROS production is increased by sevenfold (vs. control group, P < 0.01). The activity and expression of caspase-3 along with the Bax/Bcl2 ratio and the levels of p38 mitogen activated protein kinase (MAPK) phosphorylation also appeared to follow a similar trend. Furthermore, we observed that ACh could reduce up-regulation of AT1 receptor expression induced by Ang II. However, all these effects of ACh were inhibited by atropine. In conclusion, ACh prevents Ang II-induced H9c2 cells apoptosis through down-regulation of the AT1 receptor and inhibition of ROS-mediated p38 MAPK activation as well as regulation of Bcl-2, Bax and caspase-3.

Tumour necrosis factor-α and its receptors in the beneficial effects of vagal stimulation after myocardial infarction in rats.

1. Acute myocardial infarction (AMI) often activates the sympathetic system and inhibits the vagal system. Long-term vagal nerve stimulation (VNS) exerts several beneficial effects on the ischaemic heart, including an anti-inflammatory effect. The aim of the present study was to investigate whether short-term VNS during AMI could inhibit tumour necrosis factor (TNF)-α expression and the effect of TNF receptor (TNFR), key components in inflammatory responses to AMI, in a rodent model. 2. Adult male Sprague-Dawley rats were divided into four groups, namely a control (C), VNS (S), AMI (M) and an AMI group subjected to prior VNS (MS). In the S and MS groups, the right vagus nerve was stimulated electrically for 4 h; in the M and MS groups, AMI was induced by occlusion of the left anterior descending coronary artery. Haemodynamic data were monitored continuously using a multichannel physiological recorder. Lactate dehydrogenase (LDH) leakage, creatine kinase (CK) leakage and infarct size were determined. The expression of TNF-α and its receptors were analysed by reverse transcription-polymerase chain reaction, western blotting and ELISA. 3. Compared with the control group, rats in the M group had low blood pressure, high left ventricular (LV) end-diastolic pressure, a depressed maximum dP/dt of LV pressure, higher LDH and CK leakage, a larger infarct size, increased TNF-α levels and an increased TNFR1/TNFR2 ratio. However, these presumably harmful effects of AMI were all significantly ameliorated by VNS during AMI (MS group). 4. In conclusion, VNS can rectify ischaemia-induced cardiac dysfunction partly via inhibition of a TNF-α-mediated signalling pathway.

LncRNA HCP5 : A Potential Biomarker for Diagnosing Gastric Cancer.

BACKGROUND: It has been reported that long non-coding RNAs (lncRNAs) can be regarded as a biomarker and had particular clinical significance for early screening and gastric cancer (GC) diagnosis. Therefore, this study aimed to investigate whether serum HCP5 could be a new diagnostic biomarker. METHODS: Filtered out the HCP5 from the GEO database. The specificity of HCP5 was verified by real-time fluorescence quantitative PCR (qRT-PCR), and then the stability of HCP5 was verified by room temperature storage and repeated freeze-thaw experiments. Meanwhile, the accuracy of HCP5 was verified by agarose gel electrophoresis (AGE) and Sanger sequencing. Simultaneously, the expression level of serum HCP5 was detected by qRT-PCR in 98 patients with primary gastric cancer, 21 gastritis patients, 82 healthy donors, and multiple cancer types. Then, the methodology analysis was carried on. Moreover, receiver operating characteristic (ROC) was used to evaluate its diagnostic efficiency. RESULTS: qRT-PCR method had good repeatability and stability in detecting HCP5. The expression level of HCP5 in the serum of gastric cancer patients was remarkably higher than that of healthy controls, and it could distinguish gastritis patients from healthy donors. Besides, the expression of HCP5 was increased dramatically in MKN-45 and MGC-803. The FISH assay showed that HCP5 was mainly distributed in the cytoplasm of MKN-45 and BGC-823 cells. When HCP5 was combined with existing tumor markers, the diagnostic efficiency of HCP5 was the best, and the combined diagnosis of carcinoembryonic antigen (CEA), carbohydrate antigen199 (CA199), and HCP5 can significantly improve the diagnostic sensitivity. Besides, compared with the expression levels of thyroid cancer (THCA), colorectal cancer (CRC), and breast cancer (BRCA), serum HCP5 in gastric cancer was the most specific. Moreover, the high expression of serum HCP5 was related to differentiation, lymph node metastasis, and nerve invasion. The term of serum HCP5 after the operation was significantly lower than that of patients with primary gastric cancer. CONCLUSION: Serum HCP5 can be used as a potential biomarker of non-invasive fluid biopsy, which had a unique value in the early diagnosis, development, and prognosis of gastric cancer.

Circular RNA hsa_circ_0007507 May Serve as a Biomarker for the Diagnosis and Prognosis of Gastric Cancer.

PURPOSE: The morbidity and mortality of gastric cancer (GC) remain high worldwide. In recent years, circular RNAs (circRNAs) have attracted widespread attention among cancer researchers due to the stable ring structure. The present work aims to find serum circRNA biomarkers that can be used in clinical applications and effective diagnosis. METHODS: Hsa_circ_0007507 was extracted through circRNA sequencing. Exonuclease digestion assay, actinomycin D, agarose gel electrophoresis (AGE), and Sanger sequencing verified the potential of hsa_circ_0007507 as a biomarker. Besides, a real-time fluorescent quantitative polymerase chain reaction (RT-qPCR) was established to detect the level of expression of hsa_circ_0007507. Twenty cases of GC and the paired adjacent tissues were collected to verify its overexpression. Then, serum samples from 30 cases of colorectal cancer, 30 cases of thyroid cancer, and 30 cases of breast cancer were collected to verify their organ specificity. Additionally, serum samples from 80 healthy people, 62 gastritis patients, 31 intestinal metaplasia patients, and 100 GC patients were collected, and the diagnostic efficacy was evaluated through analysis of the receiver operating characteristic (ROC) curve. Furthermore, 16 post-operative GC samples, samples of 65 relapsed patients and 36 non-relapsed patients were collected to evaluate the prognosis of GC. RESULTS: The level of expression of hsa_circ_0007507 in GC tissues was up-regulated (p = 0.0121), which was consistent with the results of circRNA sequencing. Exonuclease digestion assay and actinomycin D confirmed that hsa_circ_0007507 had a stable structure and a longer half-life. In the analysis of organ specificity experiments, serum hsa_circ_0007507 did not have specificity for patients with colorectal cancer (p = 0.5319), thyroid cancer (p = 0.5422), or breast cancer (p = 0.5178). Analysis of diagnostic efficacy indicated that the expression of hsa_circ_0007507 was significantly higher than that of normal people (p <0.0001); the area under the ROC (AUC) was 0.832 (95% CI: 0.771-0.892); the diagnostic power of hsa_circ_0007507 was higher than that of CEA (AUC = 0.765, 95% CI: 0.697-0.833) and CA199 (AUC = 0.587, 95% CI: 0.504-0.67). Through diagnosis using a combination of the three, GC patients could be distinguished from normal people (AUC = 0.849), and higher diagnostic efficiency could be achieved. The expression of serum hsa_circ_0007507 in GC patients significantly decreased after surgery (p = 0.001). Besides, the expression of serum hsa_circ_0007507 in patients with post-operative recurrence was significantly up-regulated again (p = 0.0139). CONCLUSIONS: Serum hsa_circ_0007507 is differentially expressed in GC patients, post-operative GC patients, gastritis patients, intestinal metaplasia patients and relapsed patients, suggesting that serum hsa_circ_0007507 can be used as a new diagnostic and dynamic monitoring biomarker for GC.

Comprehensive Assessment of Plasma Circ_0004771 as a Novel Diagnostic and Dynamic Monitoring Biomarker in Gastric Cancer.

PURPOSE: Due to the lack of specific and sensitive detection indicators, most patients with GC are already in the advanced stage at the time of diagnosis. Therefore, it is urgent to search for effective diagnostic biomarkers that can be applied in clinic. MATERIALS AND METHODS: We screened out circ_0004771 through circRNA sequencing. Exonuclease digestion assay, agarose gel electrophoresis (AGE) and Sanger sequencing verified the potential of circ_0004771 being a biomarker. Additionally, we established quantitative real-time fluorescent polymerase chain reaction (qRT-PCR) to detect the expression level of circ_0004771 and evaluated the methodology. What's more, we collected plasma samples from 120 GC patients, 40 superficial gastritis patients, 20 postoperative GC patients, 20 postoperative recurrence patients and 120 healthy donors. We constructed the receiver operating characteristic curve (ROC) to appraise its diagnostic efficacy. RESULTS: The expression level of circ_0004771 is up-regulated in GC tissues, which is consistent with circRNA sequencing result (P=0.0001). Circ_0004771 can serve as a promising biomarker because of its stable structure and longer half-life. Plasma circ_0004771 expression is markedly richer in GC patients than that in normal people (P<0.0001), and the area under the ROC (AUC) is 0.831 (95% CI: 0.779-0.883). The diagnostic efficacy of circ_0004771 is higher than that of CEA (AUC=0.747, 95% CI: 0.686-0.808) and CA199 (AUC=0.508, 95% CI: 0.433-0.583). Higher diagnostic efficacy can be achieved by combination diagnosis for distinguishing GC patients from normal people (AUC=0.864). Besides, the expression level of circ_0004771 can distinguish GC patients from gastritis patients (AUC=0.845, 95% CI: 0.772-0.917). The plasma circ_0004771 expression in GC patients decreased to normal after surgery (P<0.0001). In addition, plasma circ_0004771 expression increased again in patients with postoperative recurrence. CONCLUSION: Plasma circ_0004771 is differentially expressed in GC patients, postoperative GC patients and patients with recurrence, suggesting that plasma circ_0004771 can be used as a novel diagnostic and dynamic monitoring biomarker in GC.

Translatable circRNAs and lncRNAs: Driving mechanisms and functions of their translation products.

Long non-coding RNA (lncRNAs) are functional RNA segments longer than 200 nucleotides, which are considered a redundant transcriptional product. Recently, lncRNAs have been shown to harbor open reading frame (ORF) sequences and encode proteins/peptides. Circular RNAs (circRNAs) have long been considered as another type of non-coding RNA (ncRNA) due to the absence of the 5' cap structure. However, recent studies have shown that they also have ORFs in their sequences. CircRNAs can be translated into proteins via internal ribosome entry site (IRES)-driven or N6-methyladenosine (m6A)-mediated initiation. To date, several translatable circRNAs and lncRNAs have been identified in Drosophila, mice, and human myoblasts, as well as in different cancers, such as glioma, hepatocellular carcinoma, and colon cancer. In this article, we review the mechanisms that drive translation of circRNAs and lncRNAs. Moreover, we discuss the research methods and tools available to identify their translation products and validate the function of these bioactive proteins/peptides in physiology and cancer.