Project description:Cutaneous T-cell lymphomas are a heterogeneous group of neoplasms originating in the skin, with mycosis fungoides (MF) and Sézary syndrome (SS) representing the most common variants. The cellular origin of cutaneous lymphomas has remained controversial due to their immense phenotypic heterogeneity that obfuscates lineage reconstruction based on classical surface biomarkers. To overcome this heterogeneity and reconstruct the differentiation trajectory of malignant cells in MF and SS, T-cell receptor sequencing was performed in parallel with targeted transcriptomics at the single-cell resolution among cutaneous samples in MF and SS. Unsupervised lineage reconstruction showed that Sézary cells exist as a population of CD4+ T cells distinct from those in patch, plaque, and tumor MF. Further investigation of malignant cell heterogeneity in SS showed that Sézary cells phenotypically comprised at least three subsets based on differential proliferation potentials and expression of exhaustion markers. A Th1 polarized cell type, intermediate cell type, and exhausted Th2 polarized cell type were identified, with Th1 and Th2 polarized cells displaying divergent proliferation potentials. Collectively, these findings provide evidence to clarify the relationship between MF and SS, and reveal cell subsets in SS that suggest a possible mechanism for therapeutic resistance.
Project description:We performed transcriptome analysis and multimodal data integration of the transcriptome and the microbiome of the skin of Mycosis fungoides Patients.
Project description:MicroRNAs are commonly aberrantly expressed in many cancers. Very little is known of their role in T-cell lymphoma, however. We therefore elucidated the complete miRNome of purified T-cells cells from 21 patients diagnosed with Sézary syndrome (SzS), a rare aggressive primary cutaneous T-cell (CD4+) lymphoma. Unsupervised cluster analysis of microarray data revealed that the microRNA expression profile was distinct from CD4+ T-cell controls and B-cell lymphomas. The majority (104/114) of SzS-associated microRNAs (P < 0.05) were down-regulated and their expression pattern was largely consistent with previously reported genomic copy number abnormalities and were found to be highly enriched (P < 0.0001) for aberrantly expressed target genes. Levels of miR-223 distinguished SzS samples (n = 32) from healthy controls (n = 19) and patients with mycosis fungoides (n = 11) in >90% of samples. Furthermore, we demonstrate that the down-regulation of intronically encoded miR-342 plays a role in the pathogenesis of SzS by inhibiting apoptosis and describe a novel mechanism of regulation for this microRNA via binding of miR-199a* to its host gene. We also provide the first in vivo evidence for down-regulation of the miR-17-92 cluster in malignancy and demonstrate that ectopic miR-17-5p expression increases apoptosis and decreases cell proliferation in SzS cells. CD4+ cells were purified from peripheral blood of 21 Sz patients and compared with 6 healthy controls.
Project description:We used targeted single cell RNA sequencing using a gene set composed of the BD Rhapsody Human Immune Response Panel, TCR panel, and a custom panel of 61 malignancy-associated genes and T/B cell receptor sequencing to characterize single cell populations in hypopigmented mycosis fungoides (HMF). Using a reference mapping model built on publically deposited classic mycosis fungoides single cell RNA sequencing datasets, we identified a predicted malignant cell population independent from the clonal T cell population in HMF.
Project description:FFPE skin biopsy samples from patients with CTCL, dermatitis, or healthy controls were profiled by NanoString gene expression analysis A classifier was constructed that was able to identify mycosis fungoides (MF) samples from dermatitis and healthy controls.
