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Objectives The aim of this study was to characterise a high biofilm-forming capacity, hypermucoviscous, blaKPC and blaNDM co-producing Klebsiella pneumoniae strain (KSH203). Methods Antimicrobial susceptibility, biofilm formation and hypermucoviscous phenotype were determined by the disk diffusion method, crystal violet staining and positive string test, respectively. Whole-genome sequencing was performed using a PacBio RS II Sequencer. High-quality reads were de novo assembled using Celera Assembler v.8.0. Genome annotation was performed using the NCBI Prokaryotic Genome Annotation Pipeline (PGAP), and the genome characteristics were analysed by bioinformatics methods. Results Klebsiella pneumoniae strain KSH203 was resistant to all antibiotics tested but was only intermediate-resistant to polymyxin B. This strain showed high biofilm-forming ability and a hypermucoviscous phenotype with serotype K25 belonging to the ST11 clone. KSH203 consists of a 5 464 059-bp single chromosome and four plasmids including pKSH203-NDM (53 144 bp), pKSH203-KPC (159 467 bp), pKSH203-CTX-M-3 (156 910 bp) and pKSH203-qnrS (253 705 bp). A total of 44 antimicrobial resistance genes and a large number virulence-associated genes were identified in the genome of strain KSH203. Conclusion In this study, we illustrate the whole genome sequence of high biofilm-forming capacity, hypermucoviscous K. pneumoniae isolate KSH203 with capsular serotype K25 belonging to ST11 isolated from a patient in China, which carried a large number of antimicrobial resistance genes and virulence-associated genes. Future studies are needed to be aware of dissemination of this type of strain among environmental, animal and human isolates.

To study the effect and underlying molecular mechanism of eugenol on CD11b+Gr1+ myeloid-derived suppressor cells (MDSCs). The effect of eugenol on the inhibition of immortalized MDSC cell line MSC-2 and murine peritoneal macrophages was detected by MTT. Flow cytometry was used to detect the pro-apoptosis effect of eugenol on MDSCs. The expression levels of apoptosis-related proteins were detected by western blot. Eugenol has a selective inhibitory effect on MDSCs in a dose-dependent manner, which activates an endogenous apoptosis pathway, leading to apoptosis. Eugenol promotes the apoptosis of MDSCs via the intrinsic pathway.

The purpose of this work was to study the effects and underlying molecular mechanisms of ligustilide on cancer-associated fibroblasts (CAFs). The effects of ligustilide on the growth of CAFs and splenocytes were detected by MTT assay, and flow cytometry was used to detect effects on T-cell proliferation. Western blotting was used to detect the expression levels of CAF-related proteins after ligustilide treatment. This study found that ligustilide had no effect on the growth of splenocytes but that it could change the immunosuppressive function of CAFs through the TLR4-NF-κB pathway and restore T-cell proliferation previously inhibited by the CAF supernatant. Thus, ligustilide is expected to be a candidate for new antitumor drugs.

Single nucleotide polymorphisms (SNPs) in tumor-related genes have been reported to play important roles in cancer development. Recent studies have shown that 3'-untranslated regions (UTR) polymorphisms are associated with the occurrence and prognosis of cancers. The aim of this study is to analyze the association between KRAS and VEGF gene 3'-UTR SNPs and genetic susceptibility to colorectal cancer (CRC). In this case-control study of 371 CRC cases and 246 healthy controls, we analyzed the association between one SNP (rs1137188G > A) in the KRAS gene and four SNPs (rs3025039C > T, rs3025040C > T, rs3025053G > A and rs10434A > G) in the VEGF gene and CRC susceptibility by the improved multiplex ligase detection reaction (iMLDR) method. We checked the selected SNPs' minor allele frequency and its distribution in the frequency of Chinese people by Hap-map database and Hardy-Weinberg equilibrium, and used multivariate logistic regression models to estimate adjusted odds ratios (AORs) and 95% confidence intervals (95% CIs). We found that the rs3025039C variant genotype in the VEGF gene was associated with a significant protection for CRC (AOR = 0.693, 95% CI = 0.485-0.989; P = 0.043 for CC and CT+TT). Nevertheless, the difference was no longer significant after Bonferroni correction (Bonferroni-adjusted P = 0.172). In genetic polymorphisms analysis, we found that the KRAS rs1137188 variant AA genotype had higher portion of tumor size (≥ 5 cm) (P = 0.01; Bonferroni-adjusted P = 0.04), which suggested that the rs1137188 variant AA genotype may significantly be associated with increased progression of CRC. In conclusion, our study suggested that these five SNPs in the KRAS gene and the VEGF gene were not associated with CRC susceptibility in Han Chinese in Sichuan province.