Multi-omics features of immunogenic cell death in gastric cancer identified by combining single-cell sequencing analysis and machine learning.

Gastric cancer (GC) is a prevalent malignancy with high mortality rates. Immunogenic cell death (ICD) is a unique form of programmed cell death that is closely linked to antitumor immunity and plays a critical role in modulating the tumor microenvironment (TME). Nevertheless, elucidating the precise effect of ICD on GC remains a challenging endeavour. ICD-related genes were identified in single-cell sequencing datasets and bulk transcriptome sequencing datasets via the AddModuleScore function, weighted gene co-expression network (WGCNA), and differential expression analysis. A robust signature associated with ICD was constructed using a machine learning computational framework incorporating 101 algorithms. Furthermore, multiomics analysis, including single-cell sequencing analysis, bulk transcriptomic analysis, and proteomics analysis, was conducted to verify the correlation of these hub genes with the immune microenvironment features of GC and with GC invasion and metastasis. We screened 59 genes associated with ICD and developed a robust ICD-related gene signature (ICDRS) via a machine learning computational framework that integrates 101 different algorithms. Furthermore, we identified five key hub genes (SMAP2, TNFAIP8, LBH, TXNIP, and PIK3IP1) from the ICDRS. Through single-cell analysis of GC tumor s, we confirmed the strong correlations of the hub genes with immune microenvironment features. Among these five genes, LBH exhibited the most significant associations with a poor prognosis and with the invasion and metastasis of GC. Finally, our findings were validated through immunohistochemical staining of a large clinical sample set, and the results further supported that LBH promotes GC cell invasion by activating the epithelial-mesenchymal transition (EMT) pathway.

The expression of hepatic carboxypeptidase E is decreased in patients with cholesterol gallstone.

BACKGROUND/AIMS: Decreased carboxypeptidase E (CPE) expression is associated with numerous pathophysiological conditions. This study aimed to investigate the potential function of hepatic CPE in cholesterol gallstone formation. PATIENTS AND METHODS: Patients with cholesterol gallstone (CGS group) and patients without cholesterol gallstones (non-CGS group) were enrolled. The serum total cholesterol, triglyceride, and biliary composition were analyzed. Eight liver samples from two patients without CGS and six patients with CGS were subjected to cDNA microarray analysis. Hepatic CPE expression was detected by quantitative real-time polymerase chain reaction (qRT-PCR), Western blot, and immunohistochemical analysis. Plasma CCK level was measured by ELISA. RESULTS: cDNA microarray identified CPE as a gene downregulated in the CGS group. RT-PCR showed that CPE mRNA level was lower in CGS group than in control (P < 0.05, t-test). Moreover, Western blot and immunohistochemistry analysis showed that CPE protein level was significantly lower in CGS group than in the control group. In addition, plasma CCK level was lower in CGS group than in the control group. A positive correlation was found between serum CCK level and hepatic CPE mRNA level (r2 = 0.713, P = 0.003). CONCLUSIONS: Down-expression of liver CPE may reduce the secretion of serum CCK and contribute to the formation of cholesterol gallstone.

Prognostic value of microRNA-145 in patients with various cancers: a meta-analysis.

BACKGROUND: MicroRNA-145 (miR-145) plays a crucial role in cancer prognosis. OBJECTIVE: This study aimed to investigate the prognostic value of miR-145 in patients with various cancers. METHODS: We pooled published literature from PubMed, EMBASE, Web of Science and Cochrane Database of Systematic Reviews and calculated the hazard ratios (HRs) with 95% confidence intervals (CIs) to estimate the correlation between miR-145 expression levels and survival of patients with general cancers. RESULTS: A total of 615 cases from 8 studies of multiple cancers were examined in this meta-analysis. The HR for overall survival (OS) of low miR-145 expression in multiple cancers was 1.80 (95% CI = 1.19-2.70). Furthermore, after excluding 1 study for its potential heterogeneity, the results suggested an increasing prognostic value of low miR-145 expression (HR = 2.20, 95% CI = 1.63-1.97). In addition, there was no significant difference between miR-145 expression levels and recurrence-free survival (RFS). CONCLUSION: In conclusion, our findings suggest that miR-145 expression is associated with OS in cancer patients and can serve as a promising biomarker for monitoring prognosis.

Effects of hypoxia-inducible factor-1α silencing on drug resistance of human pancreatic cancer cell line Patu8988/5-Fu.

The present study aimed to investigate the mechanism and the possible approaches of solving drug resistance by silencing hypoxia-inducible factor-1 alpha of human pancreatic cancer cell line Patu8988/5-Fu cultured in hypoxia. The effective jamming fragment screened by RT-PCR for silencing HIF-1α gene was transfected into pancreatic cancer cells Patu8988/5-Fu through lentivirus. RT-PCR results showed that the effective jamming fragments for HIF-1α in lentivirus transfection was Wtl-mus-1202(C546). Combined MTT with JC-1 fluorescence staining flow cytometric analysis, the concentration of 200 µmol/L CoCl2 for 8 h was chosen to mimic hypoxia cell environment. The drug resistance significantly enhanced in response to hypoxia in Patu8988/5-Fu (p<0.05), and silence HIF-1α could reverse the multidrug resistance (P<0.05). In the Patu8988/5-Fu cells, HIF-1α and MDR1 significantly increased in response to hypoxia (p<0.05). The inhibition of HIF-1α expression synergistically downregulated the expression of the MDR1 gene in Patu8988/5-Fu cells (p<0.05). HIF-1α expression was positively correlated with the MDR1 expression (p<0.05). The upregulation of the HIF-1α and MDR1 gene expression caused by hypoxia was related with the generation of multi-drug resistance of Patu8988/5-Fu, targeted silencing HIF-1α may be a kind of way to reverse the chemotherapy drug resistance.