H. pylori induces a complicated local and systematic immune response and contributes to the carcinogenesis of gastric cancer. A primary type 1 immune response is evoked by H. pylori since its occurrence. However, it is not unusual that an inhibitory immunity is dominant in H. pylori-associated diseases, which are promoted by the formation of immunosuppressive microenvironment. But whether group 2 innate lymphoid cells (ILC2s) plays a critical role in H. pylori-induced skewed type 2 immunity is still unclear. In the present study, firstly, we confirmed that type 1 immunity was inhibited and type 2 immunity were undisturbed or promoted after H. pylori infection in vitro and in vivo. Secondly, GATA-3 was firstly found to be increased in the interstitial lymphocytes from H. pylori-associated gastric cancer, among them, Lin−GATA-3⁺ cells and Lin⁺GATA-3⁺ cells were also found to be enhanced, which indicated an important role for ILC2s in H. pylori infection. More importantly, ILC2s were found to be increased after H. pylori infection in clinical patients and animal models. In conclusion, our results indicated that ILC2-mediated innate immune response might play a potential role in dominant type 2 phenotype and immunosuppressive microenvironment in H. pylori infection.

Background: The chronic infection with Helicobacter pylori (H. pylori), especially cytotoxin-associated gene A-positive (CagA⁺) strains, has been associated with various extragastric disorders. Evaluating the potential impacts of virulence factor CagA on intestine may provide a better understanding of H. pylori pathogenesis such as colitis. The intestinal mucosal barrier is essential for maintaining its integrity and functions. However, how persistent CagA⁺H. pylori colonization influences barrier disruption and thereby affects chronic colitis is not fully understood. Results: Chronic colitis models of CagA⁺H. pylori-colonized mice treated with 2% Dextran sulphate sodium (DSS) were established to assess the disease activity and pertinent expression of tight junction proteins closely related to mucosal integrity. The aggravating effect of CagA⁺H. pylori infection on DSS-induced chronic colitis was confirmed in mouse models. In addition, augmented Claudin-2 expression was detected in CagA⁺H. pylori infection conditions and selected for mechanistic analysis. Next, GES-1 human gastric epithelial cells were cultured with CagA⁺H. pylori or a recombinant CagA protein, and exosomes isolated from conditioned media were then identified. We assessed the Claudin-2 levels after exposure to CagA⁺ exosomes, CagA⁻ exosomes, and IFN-γ incubation, revealing that CagA⁺H. pylori compromised the colonic mucosal barrier and facilitated IFN-γ-induced intestinal epithelial destruction through CagA-containing exosome-mediated mechanisms. Specifically, CagA upregulated Claudin-2 expression at the transcriptional level via a CDX2-dependent mechanism to slow the restoration of wounded mucosa in colitis in vitro. Conclusions: These data suggest that exosomes containing CagA facilitate CDX2-dependent Claudin-2 maintenance. The exosome-dependent mechanisms of CagA⁺H. pylori infection are indispensable for damaging the mucosal barrier integrity in chronic colitis, which may provide a new idea for inflammatory bowel disease (IBD) treatment.

Helicobacter pylori (H. pylori) infection is closely associated with the etiology of a variety of gastric diseases. The effective eradication of H. pylori infection has been shown to reduce the incidence of gastric carcinoma. However, the rate of H. pylori eradication has significantly declined due to its increasing resistance to antibiotics, especially to clarithromycin. Therefore, the detection of clarithromycin resistance is necessary prior to the treatment of H. pylori. Although many studies have been conducted on the use of polymerase chain reaction (PCR)-based tests to detect clarithromycin resistance in stool samples, no accurate data on the feasibility of these tests are available. Here, we performed a meta-analysis to assess the feasibility of these noninvasive tests. To evaluate the reliability of PCR-based tests for detecting H. pylori clarithromycin resistance in stool samples. We searched PubMed, Medline, Embase, and other databases for articles that evaluated the value of the PCR analysis of stool samples for detecting the resistance of H. pylori to clarithromycin. We collected cross-sectional studies that met the inclusion criteria. Diagnostic accuracy measures were pooled using a random-effects model. The risk of bias was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 tool. Subgroup analysis was also conducted according to PCR type, purification technique, reference standard, mutation site, sample weight, number of patients, and age group, and the clinical utility of diagnostic tests was evaluated using the Likelihood Ratio Scatter Graph. Out of the 1818 identified studies, only 11 met the eligibility criteria, with a total of 592 patients assessed. A meta-analysis of the random-effect model showed that PCR-based analysis of stool samples had high diagnostic accuracy for detecting clarithromycin resistance in patients infected with H. pylori. The combined sensitivity was 0.91 [95% confidence interval (CI): 0.83-0.95], Q = 30.34, and I² = 67.04, and the combined specificity was 0.97 (95%CI: 0.62-1.00), Q = 279.54, and I² = 96.42. The likelihood ratio for a positive test was 33.25 (95%CI: 1.69-652.77), and that for a negative test was 0.10 (95%CI: 0.05-0.18), with an area under the curve of 0.94. The diagnostic odds ratio was 347.68 (95%CI: 17.29-6991.26). There was significant statistical heterogeneity, and the sub-analyses showed significant differences in the number of patients, sample weight, purification methods, PCR types, mutation points, and reference standards. The included studies showed no risk of publication bias. PCR-based tests on stool samples have high diagnostic accuracy for detecting H. pylori clarithromycin resistance.

Ubiquitin ligases have been shown to regulate drug sensitivity. This study aimed to explore the role of the ubiquitin ligase WD repeat and HMG-box DNA binding protein 1 (WDHD1) in regulating cisplatin sensitivity in lung adenocarcinoma (LUAD). A quantitative analysis of the global proteome identified differential protein expression between LUAD A549 cells and the cisplatin-resistant strain A549/DDP. Public databases revealed the relationship between ubiquitin ligase expression and the prognosis of patients with LUAD. Quantitative real-time polymerase chain reaction and Western blotting were used to estimate the WDHD1 expression levels. Analysis of public databases predicted the substrate of WDHD1. Western blotting detected the effect of WDHD1 on microtubule-associated protein RP/EB family member 2 (MAPRE2) and DSTN. Functional analysis of MAPRE2 verified the interaction between WDHD1 and MAPRE2, as well as the interacting sites by methyl-thiazolyl-tetrazolium assay and flow cytometry, immunoprecipitation, protein stability, and immunofluorescence. Cell and animal experiments confirmed the effect of WDHD1 and MAPRE2 on cisplatin sensitivity in LUAD. Clinical data evaluated the impact of WDHD1 expression level on cisplatin sensitivity. Quantitative analysis of the global proteome revealed ubiquitin-dependent protein catabolism to be more active in A549/DDP cells than in A549 cells. WDHD1 expression was higher in A549/DDP cells than in A549 cells, and knocking out WDHD1 increased the sensitivity of A549/DDP cells to cisplatin. WDHD1 overexpression negatively correlated with the overall survival of LUAD patients. We observed that MAPRE2 was upregulated when WDHD1 was knocked out. A MAPRE2 knockout in A549 cells resulted in increased cell viability while decreasing apoptosis when the A549 cells exposed to cisplatin. WDHD1 and MAPRE2 were found to interact in the nucleus, and WDHD1 promoted the ubiquitination of MAPRE2. Following cisplatin exposure, the WDHD1 and MAPRE2 knockout groups facilitated cell proliferation and migration, inhibited apoptosis in A549/DDP cells, decreased apoptosis, and increased tumor size and growth rate in animal experiments. Immunohistochemistry showed that Ki67 levels increased, and levels of apoptotic indicators significantly decreased in the WDHD1 and MAPRE2 knockout groups. Clinical data confirmed that WDHD1 overexpression negatively correlated with cisplatin sensitivity. Thus, the ubiquitin ligase WDHD1 induces cisplatin resistance in LUAD by promoting MAPRE2 ubiquitination.

O-GlcNAcylation is an important post-translational modification (PTM) jointly controlled by O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA). Aberrant hyper-O-GlcNAcylation is reported to yield hepatocellular carcinoma (HCC) malignancy, but the underlying mechanisms of the OGT/OGA imbalance responsible for HCC tumorigenesis remain largely unknown. Here, we report that RAN-binding protein 2 (RANBP2), one of the small ubiquitin-like modifier (SUMO) E3 ligases, contributed to malignant phenotypes in HCC. RANBP2 was found to facilitate CCAAT/enhancer-binding protein alpha (CEBPα) SUMOylation and degradation by direct interplay with CEBPα. As a transcriptional factor, CEBPα was verified to augment OGA transcription, and further experiments demonstrated that RANBP2 enhanced the O-GlcNAc level by downregulating OGA transcription while not affecting OGT expression. Importantly, we provided in vitro and in vivo evidence of HCC malignant phenotypes that RANBP2 triggered through an imbalance of OGT/OGA and subsequent higher O-GlcNAcylation events for oncogenic proteins such as peroxisome proliferative-activated receptor gamma coactivator 1 alpha (PGC1α) in a CEBPα-dependent manner. Altogether, our results show a novel molecular mechanism whereby RANBP2 regulates its function through CEBPα-dependent OGA downregulation to induce a global change in the hyper-O-GlcNAcylation of genes, such as PGC1α, encouraging the further study of promising implications for HCC therapy.

Background. Cancer affects millions of people each year and imposes a huge economic and social burden worldwide. Cuproptosis is a recently discovered novel mode of cell death. The exact function of the cuproptosis-related gene dihydrolipoamide dehydrogenase (DLD) and its role in pan-cancer is unknown. Methods. Data were retrieved from the GTEx, TCGA, and multiple online websites. These data were used to assess the expression, prognosis, and diagnostic value of DLD in various tumors. The relationship of DLD with immune microenvironment immunomodulators, immune checkpoints, tumor mutational load (TMB), microsatellite instability (MSI), and oncology drug sensitivity was explored by correlation analysis. Results. The mRNA and protein expression of DLD differs in most cancers. Survival analysis showed that DLD was associated with prognosis with KIRC, KIRP, KICH, and UCS. DLD had a strong diagnostic value in KIRC, GBM, PAAD, and LGG (AUC0.9). DLD promoter methylation affects the aberrant expression of LIHC, LUSC, PAAD, READ, and THCA. DLD was negatively correlated with stromal score, immune score, and ESTIMATE score in UCEC, TGCT, LUSC, and SARC. In UCS, resting memory CD4 T cells and activated NK cells were significantly correlated with DLD expression. Significant correlations were also observed between DLD expression and immunomodulators, immune checkpoints, TMB, and MSI in various cancers. Importantly, we also identified a number of potential drugs that may target DLD. Conclusion. DLD expression is associated with a variety of tumor prognoses and plays an integral role in tumorigenesis, tumor metabolism, and immunity.