Transcriptomic characterization and construction of M2 macrophage-related prognostic and immunotherapeutic signature in ovarian metastasis of gastric cancer.

BACKGROUND: Ovarian metastasis (OM) poses a major threat to the outcome of gastric cancer (GC) patients. Recently, immunotherapy emerged as a novel promising therapeutic strategy to treat late-stage GC, whereas its efficacy is influenced by tumor immune microenvironment (TIME). M2 macrophage, a key subset within TIME, plays dual immunosuppressive and pro-tumorigenic roles in cancer progression and is recognized as a potential therapeutic target. However, molecular mechanisms underlying OM remain elusive and the TIME-related prognostic and immunotherapeutic index for these patients is yet to establish. METHODS: Differential expressed genes (DEGs) between paired normal mucosa, primary GC and OM of patients from Fudan University Shanghai Cancer Center (FUSCC) cohort (n = 6) were identified by transcriptome sequencing, followed by the functional annotation of enriched hallmark pathways of DEGs between them. CIBERSORT was used to profile the relative expression level of 22 immune cell subsets in normal tissues, primary and metastatic tumors, followed by weighted gene coexpression network analysis (WGCNA) uncovering immune cell-correlated gene sets. The intersected genes between DEGs and M2 macrophage-related genes were processed by least absolute shrinkage and selection operator (LASSO) regression analysis to construct a predictive signature, M2GO, which was further validated by training set and test set of The Cancer Genome Atlas-Stomach Adenocarcinoma (TCGA-STAD), GSE62254 and GSE84437 cohorts. GC patients were divided into M2GO-high and -low subgroup according to the optimal cutoff value of the M2GO score. Furthermore, the clinical, molecular and immune features between M2GO-high and -low subgroups were analyzed. Clinical cohorts of immunotherapy were used to validate the predictive value of M2GO in regard to immunotherapy effectiveness. RESULTS: Transcriptomic sequencing and follow-up analyses of triple-matched normal tissues, primary and ovarian metastatic tumors identified distinctive sets of DEGs and enriched immune-, cancer- and metastasis-related pathways between them. Of note, M2 macrophage, a major immunosuppressive and pro-tumorigenic component within TIME, was significantly up-regulated in OMs. WGCNA and LASSO regression were applied to establish a novel OM- and M2 macrophage-related predictive signature, M2GO, based on M2 macrophage-related prognostic genes including GJA1, MAGED1 and SERPINE1. M2GO served as an independent prognostic factor of GC patients. Comprehensive molecular and immune characterization of M2GO-based subgroups uncovered their distinctive features in terms of enriched functional pathways, tumor mutation burden, key immune checkpoints, major regulators of natural immune cGAS-STING pathway, infiltrated subsets of immune cells and tumor immune exclusion/dysfunction (TIDE) score. Notably, the M2GO score was significantly lower in responsive group than non-responsive group (P < 0.05) in clinical cohort of metastatic GC patients undergoing immunotherapy. CONCLUSION: Transcriptomic characterization of paired normal mucosae, primary and ovarian metastatic tumors revealed their unique molecular and immune features. Follow-up analyses established a novel OM- and M2 macrophage-related signature, M2GO, which served as a promising prognostic and immunotherapeutic biomarker to distinguish the clinical outcome, molecular and immune features of GC patients and predict their differential responses to immunotherapy.

Characterization of PANoptosis patterns predicts survival and immunotherapy response in gastric cancer.

Accumulating evidence suggests that pyroptosis, apoptosis and necroptosis are deeply involved in cancer immunity. However, the role of PANoptosis in gastric cancer (GC) remains unexplored. In this study, we identified three distinct PANoptosis patterns in 1316 patients with GC, each PANoptosis pattern has its own molecular, clinical and immunological features. A scoring system named PANscore was constructed to quantify the PANoptosis patterns of the individual patients with GC. The low PANscore group had a higher response rate to immunotherapy and had a better prognosis. The predictive ability of the PANscore for prognosis and immunotherapy response was validated in multiple independent cohorts. Pan-cancer analyses showed that high PANscore was significantly associated with low expression of immune checkpoints, high expression of TGF-ß, dense infiltration of cancer-associated fibroblasts and macrophage M2. In conclusion, characterization of PANoptosis patterns provides a roadmap for patient stratification, not only in GC but also across pan-cancer.

Prognostic significance of preoperative plasma fibrinogen levels in primary gastrointestinal stromal tumours: a retrospective cohort study.

BACKGROUND: Improved prediction of prognosis for gastrointestinal stromal tumours (GISTs) has become increasingly important since the introduction of targeted therapy. Here, we aimed to evaluate the prognostic significance of preoperative plasma fibrinogen (Fib) levels in patients with primary GISTs and to analyse their correlations with clinicopathological characteristics. METHODS: A total of 201 previously untreated patients with primary GISTs who had undergone radical surgery at our institution between October 2004 and July 2018 were enrolled. The optimal cut-off value for Fib levels was calculated using time-dependent receiver-operating characteristic curve analysis. RFS, the primary endpoint, was calculated by the Kaplan-Meier method and compared by the log-rank test. Univariate and multivariate Cox regression models were calculated. RESULTS: High preoperative plasma Fib levels were detected as an independent adverse prognostic factor (p = 0.008, hazard ratio 3.136, 95% CI 1.356‒7.256). Furthermore, high preoperative plasma Fib levels also indicated a poor prognosis within the modified National Institutes of Health (mNIH) high-risk subgroup (p = 0.041). In addition, preoperative plasma Fib levels showed a positive correlation with several prognostic factors and even a linear relationship with tumour size (Spearman correlation coefficient [r] = 0.411, p < 0.001). CONCLUSIONS: Our results suggest that high preoperative plasma Fib levels may indicate a poor prognosis in patients with primary GISTs. As a cost-effective biomarker, preoperative assessment of plasma Fib levels may help to further risk stratify patients with mNIH high-risk GISTs and instruct the application of targeted therapy.

Guanine nucleotide-binding protein subunit beta-4 promotes gastric cancer progression via activating Erk1/2.

Gastric cancer (GC) is one of the most common and lethal malignancies worldwide, and its poor prognosis is mainly due to the rapid tumor progression including tumor invasion, distant metastasis, etc. Understanding the molecular mechanisms regulating GC progression lays the basis for the development of targeted therapeutic agents. Increasing evidence suggests that guanine nucleotide-binding protein subunit beta-4 (GNB4), a key subunit of heterotrimeric G protein, plays a crucial role in the initiation and progression of multiple malignancies. However, whether and how GNB4 promotes GC progression are still unknown. In this study, we found that GNB4 was highly expressed in GC tissues compared to that in non-tumor tissues and was significantly associated with tumor invasion depth, pathological stage and poor survival rate of GC patients. Both gain-of-function and loss-of-function studies revealed that GNB4 significantly enhanced GC cell growth and motility both in vitro and in vivo. Further studies revealed that GNB4 overexpression induced G1-S transition and promoted the process of epithelial-mesenchymal transformation. These tumor promoting effects were mediated by GNB4 which activates the Erk1/2 pathway through upregulating Erk1/2 phosphorylation, as U0126, an Erk1/2 phosphorylation inhibitor, could significantly inhibit GNB4-mediated cell proliferation, migration and invasion. In summary, GNB4 contributes to the proliferation and metastasis of GC cells by activating the Erk1/2 signaling pathway, and it may serve as a potential therapeutic target of GC.

Identification and development of long non-coding RNA-associated regulatory network in colorectal cancer.

Colorectal cancer (CRC) is one of the leading causes of cancer-associated death globally. Long non-coding RNAs (lncRNAs) have been identified as micro RNA (miRNA) sponges in a competing endogenous RNA (ceRNA) network and are involved in the regulation of mRNA expression. This study aims to construct a lncRNA-associated ceRNA network and investigate the prognostic biomarkers in CRC. A total of 38 differentially expressed (DE) lncRNAs, 23 DEmiRNAs and 27 DEmRNAs were identified by analysing the expression profiles of CRC obtained from The Cancer Genome Atlas (TCGA). These RNAs were chosen to develop a ceRNA regulatory network of CRC, which comprised 125 edges. Survival analysis showed that four lncRNAs, six miRNAs and five mRNAs were significantly associated with overall survival. A potential regulatory axis of ADAMTS9-AS2/miR-32/PHLPP2 was identified from the network. Experimental validation was performed using clinical samples by quantitative real-time PCR (qRT-PCR), which showed that expression of the genes in the axis was associated with clinicopathological features and the correlation among them perfectly conformed to the 'ceRNA theory'. Overexpression of ADAMTS9-AS2 in colon cancer cell lines significantly inhibited the miR-32 expression and promoted PHLPP2 expression, while ADAMTS9-AS2 knockdown had the opposite effects. The constructed novel ceRNA network may provide a comprehensive understanding of the mechanisms of CRC carcinogenesis. The ADAMTS9-AS2/miR-32/PHLPP2 regulatory axis may serve as a potential therapeutic target for CRC.

Risk Factors for Nonclosure of a Temporary Defunctioning Ileostomy Following Anterior Resection of Rectal Cancer.

BACKGROUND: In patients with colorectal cancer, a defunctioning ileostomy is commonly constructed to reduce anastomotic complications. However, many patients do not undergo a subsequent procedure to have their temporary stoma closed. OBJECTIVE: This study investigated the incidence of nonclosure of ileostomies and identified factors associated with nonclosure. DESIGN: This study is a retrospective analysis of prospectively collected data. SETTING: This study was conducted at a tertiary referral cancer hospital. PATIENTS: A total of 296 patients who received anterior resection with a defunctioning ileostomy with protective intention from 2006 to 2013 were included. MAIN OUTCOME MEASURES: The primary outcomes measured were the incidence of nonclosure of ileostomy and associated risk factors. RESULTS: Patients were followed for a median time of 29 months (range, 21-100 months). At the end of the study, 51 (17.2%) patients were left with a permanent ileostomy. The median time interval from the creation of a defunctioning ileostomy to closure was 192 days (range, 14-865 days). Multivariate analyses using a logistic regression model showed that metastatic diseases (OR, 0.179, p < 0.001), Charlson Comorbidity Index score >1 (OR, 0.268; p < 0.01), and complications from the index surgery (OR, 0.391; p = 0.013) were significant independent risk factors for failing to close a defunctioning ileostomy. LIMITATIONS: Although our study has a large patient cohort, it is limited by its retrospective nature. It is difficult to fully evaluate stoma complications after hospital discharge, and the prevalence may be underestimated. CONCLUSION: One in 6 temporary ileostomies constructed during an elective anterior resection for rectal cancer was not closed. Patients should be told before the index surgery that there is a risk of nonclosure and possible complications associated with permanent ileostomy.

Subcutaneous vacuum drains reduce surgical site infection after primary closure of defunctioning ileostomy.

PURPOSE: Surgical site infection (SSI) is the most common complication after primary closure of defunctioning ileostomy. We use a subcutaneous vacuum drain (SVD) in our institution to prevent infection. This study aimed to analyze the risk factors of SSI and to assess the utility of an SVD for preventing SSI in patients undergoing primary closure of ileostomy. METHODS: Patients undergoing ileostomy closure in the Department of Colorectal Surgery, Peking University Cancer Hospital, from September 2006 to March 2013, were included in this study. The clinical features of these patients with or without a subcutaneous drain were reviewed, and the complication rate of SSI was analyzed. The primary endpoints were the incidence and risk factors of SSI, and the secondary endpoints were the rate of overall complications and their management. RESULTS: A total of 245 consecutive patients were enrolled in the study. The overall incidence of SSI was 8.6%. Eighty-five (34.7%) patients received placement of an SVD. The use of SVDs was associated with a significantly lower incidence of SSI compared with primary closure (PC) without an SVD (1.2 vs. 12.5%, p = 0.001). Multivariate analyses showed that the presence of an SVD (odds ratio (OR) 0.063, p = 0.012), total operation time >90 min (OR 4.862, p = 0.002), and postoperative complications (OR 10.576, p < 0.001) were independent risk factors of SSI. CONCLUSIONS: This study shows that an SVD is effective for reducing SSI in patients undergoing PC of ileostomy. Further randomized trials are required to confirm our findings and to compare SVDs with purse-string sutures.

Significance of dysregulated M2 macrophage and ESR2 in the ovarian metastasis of gastric cancer.

Background: Prognosis of gastric cancer (GC) patients with ovarian metastasis (OM) remains poor. We hereby characterized the role of tumor immune microenvironment (TIME) and identified potential key regulators in the OM with the aim of understanding its molecular basis to develop novel therapeutic targets. Methods: Transcriptomic analyses of paired primary and ovarian metastatic lesions of seven GC patients from Fudan University Shanghai Cancer Center uncovered and functionally annotated their differentially expressed genes (DEGs). CIBERSORT analysis revealed differential TIME between primary GCs and OMs, which was further validated by multiplex immunofluorescence (mIF). Unique overexpression of candidate regulator in OMs was validated by an immunohistochemical (IHC) staining-based cohort study and in vitro cell growth, migration and invasion assays were conducted to characterize its function in GC progression. Results: Functional enrichment analyses of DEGs between GCs and matched OMs revealed multiple significantly dysregulated immune-related and cancer-related pathways. Distinctive subsets of immune cells, especially M2 macrophage, were selectively enriched in metastatic lesions. mIF-based quantification further validated the overexpression of CD68+CD206+ M2 macrophage in the OMs. Estrogen receptor 2 (ESR2), which encodes estrogen receptor ß (ERß), was not only potentially correlated with M2 macrophage but also overexpressed in the OM of GC. ESR2 was up-regulated in cancerous tissue and its high expression correlated with younger age, more advanced lymph node metastasis and pathological stage, as well as a worse patient survival. IHC staining of ERß in the cohort of paired primary and metastatic GCs validated its selective overexpression in OMs. Small-interfering RNAs (siRNAs)-induced knockdown of ESR2 significantly inhibited the invasion and migration of both AGS and HGC-27 GC cell lines. Conclusions: Comparative RNA-sequencing analysis revealed the dysregulated TIME, M2 macrophage in particular, between primary GC and OM. ESR2 potentially correlated with M2 macrophage and played pro-oncogenic roles in GC progression and metastasis.

CPT1C-positive cancer-associated fibroblast facilitates immunosuppression through promoting IL-6-induced M2-like phenotype of macrophage.

Cancer-associated fibroblasts (CAFs) exhibit remarkable phenotypic heterogeneity, with specific subsets implicated in immunosuppression in various malignancies. However, whether and how they attenuate anti-tumor immunity in gastric cancer (GC) remains elusive. CPT1C, a unique isoform of carnitine palmitoyltransferase pivotal in regulating fatty acid oxidation, is briefly indicated as a protumoral metabolic mediator in the tumor microenvironment (TME) of GC. In the present study, we initially identified specific subsets of fibroblasts exclusively overexpressing CPT1C, hereby termed them as CPT1C+CAFs. Subsequent findings indicated that CPT1C+CAFs fostered a stroma-enriched and immunosuppressive TME as they correlated with extracellular matrix-related molecular features and enrichment of both immunosuppressive subsets, especially M2-like macrophages, and multiple immune-related pathways. Next, we identified that CPT1C+CAFs promoted the M2-like phenotype of macrophage in vitro. Bioinformatic analyses unveiled the robust IL-6 signaling between CPT1C+CAFs and M2-like phenotype of macrophage and identified CPT1C+CAFs as the primary source of IL-6. Meanwhile, suppressing CPT1C expression in CAFs significantly decreased IL-6 secretion in vitro. Lastly, we demonstrated the association of CPT1C+CAFs with therapeutic resistance. Notably, GC patients with high CPT1C+CAFs infiltration responded poorly to immunotherapy in clinical cohort. Collectively, our data not only present the novel identification of CPT1C+CAFs as immunosuppressive subsets in TME of GC, but also reveal the underlying mechanism that CPT1C+CAFs impair tumor immunity by secreting IL-6 to induce the immunosuppressive M2-like phenotype of macrophage in GC.

Construction of ovarian metastasis-related immune signature predicting prognosis of gastric cancer patients.

BACKGROUND: Ovarian metastasis (OM) results in poor survival of gastric cancer (GC) patients. While immunotherapy has emerged as a promising approach for late-stage GC, validated immune-related prognostic signatures still remain in need. In this study, we constructed an ovarian metastasis- and immune-related prognostic signature (OMIRPS), characterized the molecular and immune features of OMIRPS-categorized subgroups and predicted their potential response to immunotherapy. METHODS: Three individual cohorts were used to construct and evaluate OMIRPS: RNA-seq of matched primary GC and OM from Fudan University Shanghai Cancer Center (FUSCC) (discovery cohort, n = 4), The Cancer Genome Atlas (TCGA) (training cohort, n = 544) and GSE84437 (validation cohort, n = 433). Differentially expressed genes (DEGs) identified between primary GC and OM and immune-related genes (IRGs) from the ImmPort and InnateDB databases were used to identify immune-related prognostic hub genes, which were further used to construct OMIRPS by using LASSO regression analysis. Prognosis, molecular characteristics, immune features, and differential immunotherapy efficacy between different OMIRPS subgroups were analyzed. RESULTS: Functional analyses of DEGs revealed the significance of immune-related signatures and pathways in the OM. Immune-related prognostic hub genes including TNFRSF18, CARD11, BCL11B, NRP1, BNIP3L, and ATF3 were utilized to construct OMIRPS, which was identified as an independent prognostic factor. Comprehensive analyses unveiled the distinctive molecular and immune characteristics of OMIRPS-high and -low subgroup in regard to enriched pathways, mutation rate, tumor mutation burden, microsatellite instability status, infiltrated immune cell, immune exclusion score, and the prediction of immunotherapy efficacy. Additionally, OMIRPS was associated with Immune Subtypes with borderline significance. CONCLUSIONS: RNA-seq of paired primary and ovarian metastatic tumors unveiled the significance of immune-related pathways and tumor immune microenvironment in OM. OMIRPS served as a promising biomarker to predict the prognosis of GC patients and distinguish the molecular features, immune characteristics, and efficacy of immunotherapy between different subgroups.

Influence of applied voltage on bioelectrochemical enhancement of biomethanation for low-rank coal and microbial community distribution.

The performance of peat biomethanation was investigated in bioelectrochemical anaerobic digestion at different applied voltages, and compared to conventional anaerobic digestion. The methane yield was stabilized at 16 mL/g peat in the conventional anaerobic digestion. However, in the bioelectrochemical anaerobic digestion, the methane yield was significantly increased to 264 mL/g peat at the applied voltage of 4 V, followed by 1 V, 2 V, 0.5 V and 0 V. The bioelectrochemical system could enrich more electroactive microorganisms on the electrode, as well as in the bulk solution, and further improve the direct interspecies electron transfer for methane production. The 16S rRNA analysis showed a significant increase in the abundance of specific microorganisms in the bulk solution, including Firmicutes phylum and Proteobacteria phylum, in addition to a gradual increase in acetoclastic methanogenesis with an increase in applied voltage. These results provide a solution to turn low-rank coal into a new alternative energy.

Immunologic Gene Sets Reveal Features of the Tumor Immune Microenvironment and Predict Prognosis and Immunotherapy Response: A Pan-Cancer Analysis.

In the treatment of cancer, anti-programmed cell death-1 (PD-1)/programmed cell death-ligand 1 (PD-L1) immunotherapy has achieved unprecedented clinical success. However, the significant response to these therapies is limited to a small number of patients. This study aimed to predict immunotherapy response and prognosis using immunologic gene sets (IGSs). The enrichment scores of 4,872 IGSs in 348 patients with metastatic urothelial cancer treated with anti-PD-L1 therapy were computed using gene set variation analysis (GSVA). An IGS-based classification (IGSC) was constructed using a nonnegative matrix factorization (NMF) approach. An IGS-based risk prediction model (RPM) was developed using the least absolute shrinkage and selection operator (LASSO) method. The IMvigor210 cohort was divided into three distinct subtypes, among which subtype 2 had the best prognosis and the highest immunotherapy response rate. Subtype 2 also had significantly higher PD-L1 expression, a higher proportion of the immune-inflamed phenotype, and a higher tumor mutational burden (TMB). An RPM was constructed using four gene sets, and it could effectively predict prognosis and immunotherapy response in patients receiving anti-PD-L1 immunotherapy. Pan-cancer analyses also demonstrated that the RPM was capable of accurate risk stratification across multiple cancer types, and RPM score was significantly associated with TMB, microsatellite instability (MSI), CD8+ T-cell infiltration, and the expression of cytokines interferon-γ (IFN-γ), transforming growth factor-ß (TGF-ß) and tumor necrosis factor-α (TNF-α), which are key predictors of immunotherapy response. The IGSC strengthens our understanding of the diverse biological processes in tumor immune microenvironment, and the RPM can be a promising biomarker for predicting the prognosis and response in cancer immunotherapy.

Development and validation of a cancer-associated fibroblast-derived lncRNA signature for predicting clinical outcomes in colorectal cancer.

Cancer-associated fibroblasts (CAFs) are actively involved in cancer progression through generating extracellular matrix and orchestrating the crosstalk within the tumor microenvironment (TME). This study aimed to develop and validate a CAF-derived lncRNA (long non-coding RNA) (CAFDL) signature for predicting clinical outcomes in colorectal cancer (CRC). Clinical data and transcriptomic profiles of 2,320 patients with CRC from The Cancer Genome Atlas (TCGA)-COAD and TCGA-READ datasets and 16 Gene Expression Omnibus datasets were included in this study. CAFDLs were identified using weighted gene co-expression network analysis. The CAFDL signature was constructed using the least absolute shrinkage and selection operator analysis in the TCGA-CRC training set. Multiple CRC cohorts and pan-cancer cohorts were used to validated the CAFDL signature. Patients with high CAFDL scores had significantly worse overall survival and disease-free survival than patients with low CAFDL scores in all CRC cohorts. In addition, non-responders to fluorouracil, leucovorin, and oxaliplatin (FOLFOX)/fluorouracil, leucovorin, and irinotecan (FOLFIRI) chemotherapy, chemoradiotherapy, bevacizumab, and immune checkpoint inhibitors had significantly higher CAFDL scores compared with responders. Pan-cancer analysis showed that CAFDL had prognostic predictive power in multiple cancers such as lung adenocarcinoma, breast invasive carcinoma, stomach adenocarcinoma, and thyroid carcinoma. The CAFDL signature was positively correlated with transforming growth factor-beta (TGF-ß) signaling, epithelial-mesenchymal transition, and angiogenesis pathways but negatively correlated with the expression of immune checkpoints such as PDCD1, CD274, and CTLA4. The CAFDL signature reflects CAF properties from a lncRNA perspective and effectively predicts clinical outcomes in CRC and across pan-cancer. The CAFDL signature can serve as a useful tool for risk stratification and provide new insights into the underlying mechanisms of CAFs in cancer immunity.

Monocyte-induced NK cell inactivation: role of reactive oxygen and nitrogen metabolites.

Here in a co-cultivation system of natural killer (NK) cells and K562 cells, monocytes (MO) and/or interleukin (IL)-2/phytohemagglutinin (PHA) were administered. After MO were administered, reactive oxygen metabolites (ROM)/reactive nitrogen metabolites (RNM) productions increased, while tumor necrosis factor (TNF)-ß/interferon (IFN)-γ levels and NK cell cytotoxicity (NCC) decreased, the changes of which after administering tiopronin (TIP) or glutamylcysteinylglycine (GSH) were opposite. In conclusions, the activated MO could inhibit the NK cell activity to kill K562 cell by secreting ROM and RNM. And TIP and GSH could scavenge both ROM and RNM to reverse the inhibitory effect of MO.

Corrigendum: EXOSC5 as a Novel Prognostic Marker Promotes Proliferation of Colorectal Cancer via Activating the ERK and AKT Pathways.

[This corrects the article DOI: 10.3389/fonc.2019.00643.].

[Effects of reactive nitrogen metabolites on NK cell-mediated killing of K562 cells].

OBJECTIVE: To explore the effects of the exogenous and endogenous reactive nitrogen metabolites (RNM) as NK cell inhibitors on NK cell-mediated killing of K562 cells and the influence of Tiopronin (TIP), glutamylcysteinylglycine (GSH) and histamine dihydrochloride (DHT) as RNM scavengers on reversing the suppressing effect of RNM. METHODS: The exogenous ONOO(-) was administered in the NK+K562 culture system, then the RNM scavengers were added in the NK+K562+ONOO(-) culture system, respectively. The concentrations of RNM, TNF-beta and IFN-gamma, K562 cell inhibition rate (KIR) and the percentage of living NK cells were examined. IL-2+PHA were used as monocyte (MO) activators in the culture system of MO+NK+K562. Then TIP, GSH and DHT were administered and the parameters of NK cell activity were analyzed. RESULTS: After exogenous ONOO(-) was administered in NK+K562 culture system, the percentage of living NK cells was decreased from (93.17 +/- 2.57)% to (71.87 +/- 1.02)% (P < 0.01) and KIR was decreased from (67.47 +/- 2.64)% to (43.44 +/- 2.87)% (P < 0.01). When TIP, GSH and DHT were administered into the systems, the percentage of living NK cells was increased to (91.13 +/- 3.67)% (P < 0.05), (88.03 +/- 1.46)% (P < 0.05), (73.60 +/- 2.76)% (P > 0.05), respectively; KIR was increased to (61.58 +/- 1.89)% (P < 0.05), (60.68 +/- 2.07)% (P < 0.05) and (45.26 +/- 3.31)% (P > 0.05), respectively. When IL-2/PHA were administered in the NK+K562+MO culture system, RNM products was increased from (82.10 +/- 6.60) micromom/L to (193.65 +/- 5.95) micromom/L(P < 0.01);KIR was decreased from (90.64 +/- 3.06)% to (61.29 +/- 2.22)% (P < 0.01). When the TIP, GSH and DHT were administered in the systems, RNM products were decreased to (91.32 +/- 6.81) micromom/L (P < 0.05), (84.66 +/- 5.99) micromom/L (P < 0.05) and (188.92 +/- 5.00) micromom/L (P > 0.05), respectively; KIR was increased to (84.31 +/- 4.56)%(P < 0.05), (81.65 +/- 3.09)% (P < 0.05) and (72.20 +/- 4.10)% (P < 0.05), respectively. CONCLUSION: NK Cell-mediated killing of K562 cells can be suppressed by exogenous and endogenous RNM administration. Both of TIP and GSH can protect NK cells by scavenging RNM and enhance the antineoplasmic activity of NK cells.

Survival-Associated Alternative Splicing Events and Prognostic Signatures in Pancreatic Cancer.

BACKGROUND: Alternative splicing (AS) is reported to be related to the biological process of multiple malignancies. This study is conducted to identify survival-associated AS events and prognostic signatures that may serve as prognostic indicators for pancreatic cancer (PC). METHODS: Univariate Cox analysis was used to determine the survival-associated AS events in PC. Prognostic signatures were constructed by LASSO Cox analysis based on seven types of survival-associated AS events. The correlation between the expression of splicing factors (SFs) and the percent spliced in values of AS events was analyzed by Pearson correlation analysis. Risk scores were calculated to determine high- or low-risk patients with different types of AS events. Gene functional annotation analysis was performed to reveal pathways in which prognostic AS is enriched. RESULTS: A total of 45,313 AS events in 10,624 genes were observed, and there were 1,565 AS events in 1,223 genes significantly correlated with overall survival for PC. Kaplan-Meier analysis, receiver-operator characteristic curve, univariate and multivariate Cox analyses showed that AS prognostic signatures could effectively predict prognosis of patients with PC. Splicing factors-AS regulatory networks were established to demonstrate the interaction between AS events and SFs. CONCLUSION: The survival-associated AS events and prognostic signatures identified in this study can serve as useful tool for predicting prognosis of patients with PC. Moreover, the SF-AS regulatory networks may provide clues for the mechanisms underlying AS in PC.

Development and Validation of an m6A RNA Methylation Regulator-Based Signature for Prognostic Prediction in Cervical Squamous Cell Carcinoma.

Background: Cervical squamous cell carcinoma (CESC) is one of the most common causes of cancer-related death worldwide. N6-methyladenosine (m6A) plays an important role in various cellular responses by regulating mRNA biology. This study aimed to develop and validate an m6A RNA methylation regulator-based signature for prognostic prediction in CESC. Methods: Clinical and survival data as well as RNA sequencing data of 13 m6A RNA methylation regulators were obtained from The Cancer Genome Atlas (TCGA) CESC database. Consensus clustering was performed to identify different CESC clusters based on the differential expression of the regulators. LASSO Cox regression analysis was used to generate a prognostic signature based on m6A RNA methylation regulator expression. The effect of the signature was further explored by univariate and multivariate Cox analyses. Results: Four regulators (RBM15, METTL3, FTO, and YTHDF2) were identified to be aberrantly expressed in CESC tissues. A prognostic signature that includes ZC3H13, YTHDC1, and YTHDF1 was developed, which can act as an independent prognostic indicator. Significant differences of survival rate and clinicopathological features were found between the high- and low-risk groups. The results of bioinformatics analysis were then validated in the clinical CESC cohort by qRT-PCR and immunohistochemistry staining. Conclusion: In the present study, we developed and validated an m6A RNA methylation regulator-based prognostic signature, which might provide useful insights regarding the development and prognosis of CESC.

Construction and Validation of an m6A RNA Methylation Regulators-Based Prognostic Signature for Esophageal Cancer.

PURPOSE: N6-methyladenosine (m6A) is reported to play a critical role in cancer through various mechanisms. We aimed to construct and validate an m6A RNA methylation regulators-based prognostic signature for Esophageal cancer (ESCA). MATERIALS AND METHODS: The RNA sequencing transcriptome data of 13 m6A RNA methylation regulators as well as clinical data were obtained from The Cancer Genome Atlas (TCGA) ESCA database. The differential expression of the regulators between ESCA tissues and normal tissues was assessed. Consensus clustering was conducted to explore the different ESCA clusters based on the expression of these regulators. LASSO Cox regression analysis was used to generate a prognostic signature based on m6A RNA methylation regulators expression. RESULTS: Eight regulators (KIAA1429, HNRNPC, RBM15, METTL3, WTAP, YTHDF1, YTHDC1, and YTHDF2) were found to be significantly upregulated in ESCA tissues. Significant differences of survival rate and clinicopathological features were found between the two clusters. A prognostic signature, which consists of HNRNPC and ALKBH5, was constructed based on the TCGA ESCA cohort, which can serve as an independent prognostic predictor. The results of bioinformatics analysis were further successfully validated in the clinical ESCA cohort by qRT-PCR and immunohistochemistry staining. CONCLUSION: Our study constructed and validated an m6A RNA methylation regulators-based prognostic signature. This might provide important information for developing diagnostic and therapeutic strategies.

WITHDRAWN: Circular RNA circUBA1 promotes gastric cancer proliferation and metastasis by acting as a competitive endogenous RNA through sponging miR-375 and regulating TEAD4.

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