BackgroundPathogenic Leptospira species cause leptospirosis, a zoonotic disease of global importance. The spirochete displays active rotative mobility which may contribute to invasion and diffusion of the pathogen in hosts. FliY is a flagellar motor switch protein that controls flagellar motor direction in other microbes, but its role in Leptospira, and paricularly in pathogenicity remains unknown.ResultsA suicide plasmid for the fliY gene of Leptospira interrogans serogroup Icterohaemorrhagiae serovar Lai strain Lai that was disrupted by inserting the ampicillin resistance gene (bla) was constructed, and the inactivation of fliY gene in a mutant (fliY-) was confirmed by PCR and Western Blot analysis. The inactivation resulted in the mRNA absence of fliP and fliQ genes which are located downstream of the fliY gene in the same operon. The mutant displayed visibly weakened rotative motion in liquid medium and its migration on semisolid medium was also markedly attenuated compared to the wild-type strain. Compared to the wild-type strain, the mutant showed much lower levels of adhesion to murine macrophages and apoptosis-inducing ability, and its lethality to guinea pigs was also significantly decreased.ConclusionInactivation of fliY, by the method used in this paper, clearly had polar effects on downstream genes. The phentotypes observed, including lower pathogenicity, could be a consequence of fliY inactivation, but also a consequence of the polar effects.
The red‐spotted grouper Epinephelus akaara (E. akaara) is one of the most economically important marine fish in China, Japan and South‐East Asia and is a threatened species. The species is also considered a good model for studies of sex inversion, development, genetic diversity and immunity. Despite its importance, molecular resources for E. akaara remain limited and no reference genome has been published to date. In this study, we constructed a chromosome‐level reference genome of E. akaara by taking advantage of long‐read single‐molecule sequencing and de novo assembly by Oxford Nanopore Technology (ONT) and Hi‐C. A red‐spotted grouper genome of 1.135 Gb was assembled from a total of 106.29 Gb polished Nanopore sequence (GridION, ONT), equivalent to 96‐fold genome coverage. The assembled genome represents 96.8% completeness (BUSCO) with a contig N50 length of 5.25 Mb and a longest contig of 25.75 Mb. The contigs were clustered and ordered onto 24 pseudochromosomes covering approximately 95.55% of the genome assembly with Hi‐C data, with a scaffold N50 length of 46.03 Mb. The genome contained 43.02% repeat sequences and 5,480 noncoding RNAs. Furthermore, combined with several RNA‐seq data sets, 23,808 (99.5%) genes were functionally annotated from a total of 23,923 predicted protein‐coding sequences. The high‐quality chromosome‐level reference genome of E. akaara was assembled for the first time and will be a valuable resource for molecular breeding and functional genomics studies of red‐spotted grouper in the future.
Metastatic castration-resistant prostate cancer (PC) is the final stage of PC that acquires resistance to androgen deprivation therapies (ADT). Despite progresses in understanding of disease mechanisms, the specific contribution of the metastatic microenvironment to ADT resistance remains largely unknown. The current study identified that the macrophage is the major microenvironmental component of bone-metastatic PC in patients. Using a novel in vivo model, we demonstrated that macrophages were critical for enzalutamide resistance through induction of a wound-healing–like response of ECM–receptor gene expression. Mechanistically, macrophages drove resistance through cytokine activin A that induced fibronectin (FN1)-integrin alpha 5 (ITGA5)–tyrosine kinase Src (SRC) signaling cascade in PC cells. This novel mechanism was strongly supported by bioinformatics analysis of patient transcriptomics datasets. Furthermore, macrophage depletion or SRC inhibition using a novel specific inhibitor significantly inhibited resistant growth. Together, our findings elucidated a novel mechanism of macrophage-induced anti-androgen resistance of metastatic PC and a promising therapeutic approach to treat this deadly disease.
Bladder cancer has a high recurrence rate and requires adjuvant intravesical management after surgery. The use of traditional agents for bladder cancer therapy is constrained by their toxicity and limited efficacy. This emphasizes the need for the development of safer, more effective compounds such as instillation agents. Curcumin is the major component of turmeric, the powdered root of Curcuma longa, which is known for its anti-inflammatory, anti-oxidant and anticancer properties. First, a microarray profiling and qPCR analysis were conducted in the T24 and SV-HUC-1 cell lines. Then, we examined the potential tumorigenicity of miR-7641 in the T24 and SV-HUC-1 cell lines with or without curcumin. Western blot analysis showed that p16 is a target of miR-7641 in T24 cells. We found that, for the first time, curcumin directly downregulates a tumor-promoting microRNA (miRNA), miR-7641, in bladder cancer, which has tumor-promoting characteristics. Curcumin induces the downregulation of miR-7641 and subsequent upregulation of p16 which is a target of miR-7641 at the post-transcriptional level, which leads to the decreased invasion and increased apoptosis of bladder cancer cells. This is the first report to show a direct effect of curcumin on inducing changes in a miRNA suppressor with direct anticancer consequences in bladder cancer. Our study shows that curcumin may be a candidate agent for the clinical management of non-muscle-invasive bladder cancer.
Background/Aims: Emerging studies have shown that the neutrophil-lymphocyte ratio (NLR) is a potential predictor in various tumors. Our study was conducted to assess the prognostic value of the pretreatment NLR in bladder cancer and metastatic or unresectable urothelial carcinoma (mUC or uUC) patients up to July 2017. The correlation between the pretreatment NLR and pathological characteristics was also evaluated in bladder cancer patients. Methods: The hazard ratio (HR) and odds ratio (OR) with the 95% confidence interval (CI) were extracted or calculated from the included studies for further pooled analysis. A total of 21 studies were included in a pooled analysis. Results: The pooled results indicated that a high pretreatment NLR was associated with reduced overall survival (OS) (HR=1.27, 95% CI=1.12-1.43), relapse-free survival (RFS) (HR=1.41, 95% CI=1.23-1.60), progression-free survival (PFS) (HR=1.75, 95% CI=1.36-2.15), disease-specific survival (DSS) and cancer-specific survival (CSS) (HR=1.27, 95% CI=1.19-1.35) in the bladder cancer patients. Additionally, an elevated pretreatment NLR suggested a worse OS rate in the mUC or uUC patients (HR=1.63, 95% CI=1.34-1.91). The pooled ORs and 95% CIs showed that a high pretreatment NLR could be a risk indicator for certain pathological features, such as lymphovascular invasion, a positive margin status and advanced tumor stage. Conclusions: our results showed that a high pretreatment NLR predicted poor prognosis in bladder cancer, mUC and uUC patients.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.