Comprehensive characterization of pyroptosis phenotypes with distinct tumor immune profiles in gastric cancer to aid immunotherapy.

OBJECTIVE: Pyroptosis is a form of programmed cell death that is essential for immunity. Herein, this study was conducted to uncover the implication of pyroptosis in immunomodulation and tumor microenvironment (TME) in gastric cancer. METHODS: Prognostic pyroptosis-related genes were extracted to identify different pyroptosis phenotypes and pyroptosis genomic phenotypes via unsupervised clustering analysis in the gastric cancer meta-cohort cohort (GSE15459, GSE62254, GSE84437, GSE26253 and TCGA-STAD). The activation of hallmark gene sets was quantified by GSVA and immune cell infiltration was estimated via ssGSEA and CIBERSORT. Through PCA algorithm, pyroptosis score was conducted. The predictors of immune response (TMB and IPS) and genetic mutations were evaluated. The efficacy of pyroptosis score in predicting immune response was verified in two anti-PD-1 therapy cohorts. RESULTS: Three different pyroptosis phenotypes with different prognosis, biological pathways and tumor immune microenvironment were established among 1275 gastric cancer patients, corresponding to three immune phenotypes: immune-inflamed, immune-desert, and immune-excluded. According to the pyroptosis score, patients were separated into high and low pyroptosis score groups. Low pyroptosis score indicated favorable survival outcomes, enhanced immune responses, and increased mutation frequency. Moreover, low pyroptosis score patients displayed more clinical benefits from anti-PD-1 and prolonged survival time. CONCLUSION: Our findings uncovered a nonnegligible role of pyroptosis in immunomodulation and TME multiformity and complicacy in gastric cancer. Quantifying the pyroptosis score in individual tumors may tailor more effective immunotherapeutic strategies.

A Novel Exosome-Relevant Molecular Classification Uncovers Distinct Immune Escape Mechanisms and Genomic Alterations in Gastric Cancer.

Objective: Gastric cancer (GC) is a highly heterogeneous malignant carcinoma. This study aimed to conduct an exosome-based classification for assisting personalized therapy for GC. Methods: Based on the expression profiling of prognostic exosome-related genes, GC patients in The Cancer Genome Atlas (TCGA) cohort were classified using the unsupervised consensus clustering approach, and the reproducibility of this classification was confirmed in the GSE84437 cohort. An exosome-based gene signature was developed via Least Absolute Shrinkage and Selection Operator (LASSO) regression analysis. Immunological features, responses to immune checkpoint inhibitors, and genetic alterations were evaluated via computational methods. Results: Two exosome-relevant phenotypes (A and B) were clustered, and this classification was independent of immune subtypes and TCGA subtypes. Exosome-relevant phenotype B had a poorer prognosis and an inflamed tumor microenvironment (TME) relative to phenotype A. Patients with phenotype B presented higher responses to the anti-CTLA4 inhibitor. Moreover, phenotype B occurred at a higher frequency of genetic mutation than phenotype A. The exosome-based gene signature (GPX3, RGS2, MATN3, SLC7A2, and SNCG) could independently and accurately predict GC prognosis, which was linked to stromal activation and immunosuppression. Conclusion: Our findings offer a conceptual frame to further comprehend the roles of exosomes in immune escape mechanisms and genomic alterations of GC. More work is required to evaluate the reference value of exosome-relevant phenotypes for designing immunotherapeutic regimens.

DNAH2 is a novel candidate gene associated with multiple morphological abnormalities of the sperm flagella.

Multiple morphological abnormalities of flagella (MMAF) is one kind of severe teratozoospermia. Gene mutations reported in previous works only revealed the pathogenesis of approximately half of the MMAF cases, and more genetic defects in MMAF need to be explored. In the present study, we performed a genetic analysis on Han Chinese men with MMAF using whole-exome sequencing. After filtering out the cases with known gene mutations, we identified five novel mutation sites in the DNAH2 gene in three cases from three families. These mutations were validated through Sanger sequencing and absent in all control individuals. In silico analysis revealed that these DNAH2 variations are deleterious. The spermatozoa with DNAH2 mutations showed severely disarranged axonemal structures with mitochondrial sheath defection. The DNAH2 protein level was significantly decreased and inner dynein arms were absent in the spermatozoa of patients. ICSI treatment was performed for two MMAF patients with DNAH2 mutations and the associated couples successfully achieved pregnancy, indicating good nuclear quality of the sperm from the DNAH2 mutant patients. Together, these data suggest that the DNAH2 mutation can cause severe sperm flagella defects that damage sperm motility. These results provide a novel genetic pathogeny for the human MMAF phenotype.

Curcumin inhibits hepatocellular carcinoma growth by targeting VEGF expression.

Morbidity and mortality owing to hepatocellular carcinoma (HCC), the most common primary liver cancer, has increased in recent years. Curcumin is a polyphenol compound that has been demonstrated to exert effective antiangiogenic, anti-inflammatory, antioxidant, and antitumor effects. However, its clinical effects in HCC remain elusive. The main aim of the present study was to determine the antiangiogenic effects of curcumin in HCC. H22HCC cells were treated with different concentrations of curcumin in vitro. In addition, a mouse xenograft model was used and analyzed for expression levels of vascular endothelial growth factor (VEGF) protein and proteins of the phosphoinositide 3-kinase (PI3K)/AKT serine/threonine kinase 1 (AKT) signaling pathway. Curcumin treatment inhibited H22 cell proliferation and promoted H22 cell apoptosis in a dose-dependent manner in vitro. In addition, curcumin treatment inhibited tumor growth in vivo at the concentrations of 50 and 100 mg/kg. Furthermore, curcumin treatment significantly decreased VEGF expression and PI3K/AKT signaling. The present findings demonstrated that curcumin inhibited HCC proliferation in vitro and in vivo by reducing VEGF expression.

[Expression and clinical significance of secretory leucocyte protease inhibitor in colon carcinoma].

OBJECTIVE: To investigate the expression of secretory leucocyte protease inhibitor (SLPI) in colon cancer and their clinical significance. METHODS: Immunohistochemistry was performed to detect the SLPI expression in colon cancer tissue microarray. The expression of SLPI was scored by two pathologists and was analyzed using Χ(2) test to explore its influence on the pathologic characteristics of colon carcinoma. RESULTS: SLPI was up-regulated in colon cancer tissue compared to normal mucosa. Overexpression of SLPI protein was correlated with differentiation grade (low differentiation: 42.1% vs 57.9%; moderate/well differentiation: 2.3% vs 97.7%, TNM stages(III-IV:29.4% vs 70.6%;I-II:3.1% vs 96.9%), lymph node metastasis (28.6% vs 71.4%) and distant metastasis (84.6% vs 15.4%), but not with patient age or sex. CONCLUSION: SLPI overexpression correlates with aggressive pathologic characteristics of colon cancer and it may server as prognostic factor of colon cancer patients. Further research will be carried out to verify whether SLPI can become a new target for colon cancer treatment.