Role of Cathepsins in Mycobacterium tuberculosis Survival in Human Macrophages

International audienc

Circulating miRNA expression in long-standing type 1 diabetes mellitus

Abstract Type 1 diabetes is a chronic autoimmune disease which results in inefficient regulation of glucose homeostasis and can lead to different vascular comorbidities through life. In this study we aimed to analyse the circulating miRNA expression profile of patients with type 1 diabetes, and with no other associated pathology. For this, fasting plasma was obtained from 85 subjects. Next generation sequencing analysis was firstly performed to identify miRNAs that were differentially expressed between groups (20 patients vs. 10 controls). hsa-miR-1-3p, hsa-miR-200b-3p, hsa-miR-9-5p, and hsa-miR-1200 expression was also measured by Taqman RT-PCR to validate the observed changes (34 patients vs. 21 controls). Finally, through a bioinformatic approach, the main pathways affected by the target genes of these miRNAs were studied. Among the studied miRNAs, hsa-miR-1-3p expression was found significantly increased in patients with type 1 diabetes compared to controls, and positively correlated with glycated haemoglobin levels. Additionally, by using a bioinformatic approach, we could observe that changes in hsa-miR-1-3p directly affect genes involved in vascular development and cardiovascular pathologies. Our results suggest that, circulating hsa-miR-1-3p in plasma, together with glycaemic control, could be used as prognostic biomarkers in type 1 diabetes, helping to prevent the development of vascular complications in these patients

Rifapentine and isoniazid once a week versus rifampicin and isoniazid twice a week for treatment of drug-susceptible pulmonary tuberculosis in HIV-negative patients: A randomised clinical trial

Background: Rifapentine has a long half-life in serum, which suggests a possible treatment once a week for tuberculosis. We aimed to compare rifapentine and isoniazid once a week with rifampicin and isoniazid twice a week. Methods: We did a randomised, multicentre, open-label trial in the USA and Canada of HIV-negative people with drug-susceptible pulmonary tuberculosis who had completed 2 months of a 6-month treatment regimen. We randomly allocated patients directly observed treatment with either 600 mg rifapentine plus 900 mg isoniazid once a week or 600 mg rifampicin plus 900 mg isoniazid twice a week. Primary outcome was failure/relapse. Analysis was by intention to treat. Findings: 1004 patients were enrolled (502 per treatment group). 928 successfully completed treatment, and 803 completed the 2-year 4-month study. Crude rates of failure/relapse were 46/502 (9.2%) in those on rifapentine once a week, and 28/502 (5.6%) in those given rifampicin twice a week (relative risk 1.64, 95% CI 1.04-2.58, p=0.04). By proportional hazards regression, five characteristics were independently associated with increased risk of failure/relapse: sputum culture positive at 2 months (hazard ratio 2.8, 95% CI 1.7-4.6); cavitation on chest radiography (3.0, 1.6-5.9); being underweight (3.0, 1.8-4.9); bilateral pulmonary involvement (1.8, 1.0-3.1); and being a non-Hispanic white person (1.8, 1.1-3.0). Adjustment for imbalances in 2-month culture and cavitation diminished the association of treatment group with outcome (1.34; 0.83-2.18; p=0.23). Of participants without cavitation, rates of failure/relapse were 6/210 (2.9%) in the once a week group and 6/241 (2.5%) in the twice a week group (relative risk 1.15; 95% CI 0.38-3.50; p=0.81). Rates of adverse events and death were similar in the two treatment groups. Interpretation: Rifapentine once a week is safe and effective for treatment of pulmonary tuberculosis in HIV-negative people without cavitation on chest radiography. Clinical, radiographic, and microbiological data help to identify patients with tuberculosis who are at increased risk of failure or relapse when treated with either regimen

Formation of an invasion-permissive matrix requires TGFβ/SNAIL1-regulated alternative splicing of fibronectin

Background: As in most solid cancers, the emergence of cells with oncogenic mutations in the mammary epithelium alters the tissue homeostasis. Some soluble factors, such as TGFβ, potently modify the behavior of healthy stromal cells. A subpopulation of cancer-associated fibroblasts expressing a TGFβ target, the SNAIL1 transcription factor, display myofibroblastic abilities that rearrange the stromal architecture. Breast tumors with the presence of SNAIL1 in the stromal compartment, and with aligned extracellular fiber, are associated with poor survival prognoses. Methods: We used deep RNA sequencing and biochemical techniques to study alternative splicing and human tumor databases to test for associations (correlation t-test) between SNAIL1 and fibronectin isoforms. Three-dimensional extracellular matrices generated from fibroblasts were used to study the mechanical properties and actions of the extracellular matrices on tumor cell and fibroblast behaviors. A metastatic mouse model of breast cancer was used to test the action of fibronectin isoforms on lung metastasis. Results: In silico studies showed that SNAIL1 correlates with the expression of the extra domain A (EDA)-containing (EDA+) fibronectin in advanced human breast cancer and other types of epithelial cancers. In TGFβ-activated fibroblasts, alternative splicing of fibronectin as well as of 500 other genes was modified by eliminating SNAIL1. Biochemical analyses demonstrated that SNAIL1 favors the inclusion of the EDA exon by modulating the activity of the SRSF1 splicing factor. Similar to Snai1 knockout fibroblasts, EDA- fibronectin fibroblasts produce an extracellular matrix that does not sustain TGFβ-induced fiber organization, rigidity, fibroblast activation, or tumor cell invasion. The presence of EDA+ fibronectin changes the action of metalloproteinases on fibronectin fibers. Critically, in an mouse orthotopic breast cancer model, the absence of the fibronectin EDA domain completely prevents lung metastasis. Conclusions: Our results support the requirement of EDA+ fibronectin in the generation of a metastasis permissive stromal architecture in breast cancers and its molecular control by SNAIL1. From a pharmacological point of view, specifically blocking EDA+ fibronectin deposition could be included in studies to reduce the formation of a pro-metastatic environment.This study was funded by grants awarded to AGH and JB by the Agencia Estatal de Investigación (AEI) del Ministerio de Ciencia e Innovación MCIN (Proyecto PID2019-104698RB-I00 financiado por MCIN/ AEI/10.13039/501100011033, y pProyecto PID2022-136968OB-I00 financiado por MCIN/AEI /10.13039/501100011033/ y por FEDER Una manera de hacer Europa)