Background: Lung cancer (LC) is one of the most aggressive, prevalent and fatal malignancies. Gut microbes and their associated metabolites are thought to cause and modulate LC development, albeit influenced by the host genetic make-up and environment. Herein, we identified and classified gut microbiota and serum metabolites associated with LC. Methods: Stool samples were collected from 41 LC patients and 40 healthy volunteers. The gut microbiota was analyzed using 16S rRNA gene sequencing. Serum samples were collected from the same LC patients (n=30) and healthy volunteers (n=30) and serum metabolites were analyzed using liquid chromatography-mass spectrometry (LC-MS). Microbiome and metabolome data were analyzed separately and integrated for combined analysis using various bioinformatics methods. Results: Serum metabolomics uncovered 870 metabolites regulated in 76 metabolic pathways in both groups. Microbial diversity analyses identified 15967 operational taxonomic units (OTUs) in groups. Of these, the abundance of 232 OTUs was significantly different between HC and LC groups. Also, serum levels of glycerophospholipids (LysoPE 18:3, LysoPC 14:0, LysoPC 18:3), Imidazopyrimidines (Hypoxanthine), AcylGlcADG 66:18; AcylGlcADG (22:6/22:6/22:6) and Acylcarnitine 11:0 were substantially different between HC and LC groups. Combined analysis correlated LC-associated microbes with metabolites, such as Erysipelotrichaceae_UCG_003, Clostridium and Synergistes with glycerophospholipids. Conclusions: There is an intricate relationship between gut microbiome and levels of several metabolites such as glycerophospholipids and imidazopyrimidines. Microbial-associated metabolites are potential diagnostic biomarkers and therapeutic targets for LC.
Introduction This study was designed to identify a group of bacteria in the human gut microbiota with specific effects on PD-1-based immunotherapy for patients with non-small cell lung cancer (NSCLC). Methods The study was performed in patients with advanced NSCLC, who received PD-1 monoclonal antibody (mAb) treatment for 6 months after one or several prior therapies. The combination of blood immune-related factors of the participants and their 16S rRNA gene sequencing from fecal samples at baseline was used to investigate the diversity and composition of the gut microbiota. The differences in relative abundance of gut microbiota at the genus level were compared, and the relation to blood immune-related factors was assessed using Spearman’s rank correlation coefficient analysis. Results The 16S rRNA gene sequencing showed a clear difference in the diversity and composition of the gut microbiota between groups with stable disease (SD) and progressive disease (PD). A comparison of differences in relative abundance at the genus level showed that the relative abundance of Escherichia-Shigella, Akkermansia and Olsenella in the SD group was significantly higher than that in the PD group. The SD group had significantly higher interleukin-12 (IL-12) and interferon γ (IFN-γ) levels than the PD group. Interestingly, the numbers of white blood cells and sorted cells in the SD group were higher than those in the PD group. Spearman’s rank correlation coefficient analysis showed that Escherichia-Shigella was positively correlated with IL-12, IFN-γ and basophils. Akkermansia was positively correlated with monocytes. Conclusion The response to PD-1-based immunotherapy in patients with NSCLC is affected by the diversity and composition of the gut microbiota. Escherichia-Shigella and Akkermansia may have specific effects on PD-1 inhibitory immunotherapy for NSCLC.
26 April 2022 in Journal of Microbiology, Immunology and Infection
The Omicron (B.1.1.529) variant was first reported in South Africa and rapidly spread worldwide in early November 2021. This caused panic in various countries, so it is necessary to understand Omicron Variant. This paper summarizes omicron variant-related research achievements. Studies have shown that Omicron Variant contains many mutations that make it more infectious and transmissible. At the same time, immune escape is also caused, resulting in reduced efficacy of existing vaccines, increased risk of reinfection, treatment failure or reduction of monoclonal antibody therapies, and detection failure. However, current data indicate that Omicron Variant causes mild clinical symptoms and few severe cases and deaths. Omicron Variant is valid for a range of nonpharmaceutical interventions against SARS-CoV-2. Improving diagnostic accuracy and enabling timely isolation and treatment of diagnosed cases is also critical to interrupting the spread of omicron variants. COVID-19 vaccine boosters could undoubtedly help control Omicron spread and infection. However, developing a vaccine specific to Omicron Variant is also imminent.
22 March 2018 in Annals of Clinical Microbiology and Antimicrobials
Clarithromycin (CLR) resistance has become a predominant factor for treatment failure of Helicobacter pylori eradication. Although the molecular mechanism of CLR resistance has been clearly understood in H. pylori, it is lack of evidence of other genes involved in drug resistance. Furthermore, the molecular mechanism of phenotype susceptible to CLR while genotype of 23S rRNA is mutant with A2143G is unclear. Here, we characterized the mutations of CLR-resistant and -susceptible H. pylori strains to explore bacterial resistance. In the present study, the whole genomes of twelve clinical isolated H. pylori strains were sequenced, including two CLR-susceptible strains with mutation of A2143G. Single nucleotide variants (SNVs) were extracted and analyzed from multidrug efflux transporter genes. We did not find mutations associated with known CLR-resistant sites except for controversial T2182C outside of A2143G in the 23S rRNA gene. Although total SNVs of multidrug efflux transporter gene and the SNVs of HP0605 were significant differences (P ≤ 0.05) between phenotype resistant and susceptible strains. There is no significant difference in SNVs of RND or MFS (HP1181) family. However, the number of mutations in the RND family was significantly higher in the mutant strain (A2143G) than in the wild type. In addition, three special variations from two membrane proteins of mtrC and hefD were identified in both CLR-susceptible strains with A2143G. Next-generation sequencing is a practical strategy for analyzing genomic variation associated with antibiotic resistance in H. pylori. The variations of membrane proteins of the RND family may be able to participate in the regulation of clinical isolated H. pylori susceptibility profiles.