Project description:Dermatomyositis is a cutaneous and muscular auto-immune condition associated with specific autoantibodies. MDA5 antibody-associated DM has higher mortality. We demonstrate here for the first time using skin microarray analysis that MDA5+ DM is associated with a greater type I interferon skin signature than MDA5- DM, mainly involving the IFN- κ member produced by skin keratinocytes
Project description:The purpose of this study was to use global gene expression analysis to determine major functional pathways and genes dysregulated in the skin of active rashes of dermatomyositis patients. These data will be used to help assign a diagnosis to skin biopsies from patients with rashes that are not clearly dermatomyositis. In addition, we will correlate gene expression changes with specific histopathologic changes in skin biopsies that are taken adjacent to those analyzed for gene expression analysis. Finally, these data will be used to search for genes and pathways that are associated with clinical outcomes and autoantibody status in this cohort of patients. Gene expression profiling of healthy donor and dermatomyositis patient skin biopsy specimens.
Project description:The purpose of this study was to use global gene expression analysis to determine major functional pathways and genes dysregulated in the skin of active rashes of dermatomyositis patients. These data will be used to help assign a diagnosis to skin biopsies from patients with rashes that are not clearly dermatomyositis. In addition, we will correlate gene expression changes with specific histopathologic changes in skin biopsies that are taken adjacent to those analyzed for gene expression analysis. Finally, these data will be used to search for genes and pathways that are associated with clinical outcomes and autoantibody status in this cohort of patients.
Project description:Genomic and epigenomic studies support that adenocarcinomas of the gallbladder develop according to a metaplasia-biliary intraepithelial neoplasia (BilIN)-adenocarcinoma histogenic sequence, in which metaplasia and BilIN are non-cancerous lesions of the epithelium. Moreover, recent genomic data suggest that adenocarcinoma can develop in a BilIN-dependent or -independent way, pointing toward patient-specific tumourigenic processes. Spatial transcriptomic data addressing these processes are still missing. Here, using GeoMx digital spatial profiling (NanoString), we characterized the spatial transcriptome of normal gallbladder epithelium, BilINs and adenocarcinoma coexisting within the same samples. To address intra-patient variability we profiled the whole transcriptome of a high number of regions of interest (ROIs) per sample in two patients (Patient #1, 81 year old woman: 24 ROIs; Patient #2, 53-year old man:32 ROIs), with each ROI covering approximately 200 cells of normal epithelium, low-grade BilIN, high-grade BilIN or adenocarcinoma. Our results showed that each type of lesion displayed little transcriptomic variability within the same patient, but differed significantly between patients. They also suggested that adenocarcinoma can derive from high-grade BilIN or from low-grade BilIN, with co-existing high-grade BilIN evolving via a distinct process in the latter case. We also provide strong evidence for patient-specific tumourigenic mechanisms, characterized by distinct sequences of signalling pathway activation. Among those pathways, we functionally investigated SEMAPHORIN 4A (SEMA4A) and provided evidence that repression of SEMA4A expression, as is observed in the gallbladder samples of the two patients, can enhance cell migration and survival, and perturb polarisation of the epithelial cells. In conclusion, our results support that gallbladder adenocarcinoma develops according to patient-specific processes that can be promoted by repression of SEMA4A. They underscore the need to gain gene expression data in addition to histological information to evaluate the risk of low-grade preneoplastic lesions.
Project description:This study aimed to investigate the expression of microRNAs (miRNAs) in the plasma from polymyositis (PM) and dermatomyositis (DM) patients, which fluctuated by treatment. More differentially expressed miRNAs were found in plasma of DM patients compared to PM patients before and after treatment, and their profiles were different.