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Dorando, H. K.

Publications and source records attributed to Dorando, H. K..

3 recordsLinked to original sources

Single Cell Resolution Tracking of Cutaneous T-Cell Lymphoma Reveals Clonal Evolution in Disease Progression

Cutaneous T-cell lymphoma (CTCL) remains a challenging disease due to its significant heterogeneity, therapy resistance, and relentless progression. Multi-omics technologies offer the potential to provide uniquely precise views of disease progression and response to therapy. We present here a comprehensive multi-omics view of CTCL clonal evolution, incorporating exome, whole genome, epigenome, bulk-, single cell (sc) VDJ-, and scRNA-sequencing of 114 clinically annotated serial skin, peripheral blood, and lymph node samples from 35 CTCL patients. We leveraged this extensive dataset to define the molecular underpinnings of CTCL progression in individual patients at single cell resolution with the goal of identifying clinically useful biomarkers and therapeutic targets. Our studies identified a large number of recurrent progression-associated clonal genomic alterations; we highlight mutation of CCR4, PI3K signaling, and PD-1 checkpoint pathways as evasion tactics deployed by malignant T cells. We also identified a gain of function mutation in STAT3 (D661Y) and demonstrated by CUT&RUN-seq that it enhances binding to transcription start sites of genes in Rho GTPase pathways, which we previously reported to have activated chromatin and increased expression in HDACi-resistant CTCL. These data provide further support for a previously unrecognized role for Rho GTPase pathway dysregulation in CTCL progression. A striking number of progression-associated mutations occurred in chromatin methylation modifiers, including EZH2, suggesting that EZH1/2 inhibition may also benefit patients with CTCL. Knowledge of these molecular changes should be leveraged for improved disease monitoring, biomarker-informed clinical trial design, and new therapeutic strategies in this challenging and incurable cancer.

cancer biology↗

LAIR1 prevents excess inflammatory tissue damage in S. aureus skin infection and Cutaneous T-cell Lymphoma

Patients with cutaneous T cell lymphoma (CTCL) experience high morbidity and mortality due to S. aureus skin infections and sepsis, but the causative immune defect is unclear. We previously identified high levels of LAIR2, a decoy protein for the inhibitory receptor LAIR1, in advanced CTCL. Mice do not have a LAIR2 homolog, so we used Lair1 knock-out (KO) mice to model LAIR2 overexpression. In a model of subcutaneous S. aureus skin infection, Lair1 KO mice had significantly larger abscesses and areas of dermonecrosis compared to WT. Lair1 KO exhibited a pattern of increased inflammatory responses in infection and sterile immune stimulation, including increased production of proinflammatory cytokines and myeloid chemokines, neutrophil ROS, and collagen/ECM remodeling pathways. Notably, Lair1 KO infected skin had a similar bacterial burden and neutrophils and monocytes had equivalent S. aureus phagocytosis compared to WT. These findings support a model in which lack of LAIR1 signaling causes an excessive inflammatory response that does not improve infection control. CTCL skin lesions harbored similar patterns of increased expression in cytokine and collagen/ECM remodeling pathways, suggesting that high levels of LAIR2 in CTCL recapitulates Lair1 KO, causing inflammatory tissue damage and compromising host defense against S. aureus infection.

immunology↗

Epigenetic regulation of Leukocyte associated immunoglobulin-like receptors 1 and 2 by interferon signaling in macrophages and T cells

BackgroundInhibitory immune receptors are important for maintaining immune homeostasis. We recently identified epigenetic alterations in two members of this group, LAIR1 and LAIR2, in patients with inflammatory tissue damage and recurrent skin and soft tissue infections. We therefore hypothesized that the expression of LAIR1 and LAIR2 may be controlled by immune stimuli acting on discrete transcriptional regulatory elements. MethodsWe used flow cytometry, qRT-PCR, and RNAseq to assay LAIR1 and LAIR2 expression in human and murine immune cell subsets at baseline and post-treatment with immune mediators, including type I and II interferons, tumor necrosis factor-alpha (TNF-[a]), and lipopolysaccharide (LPS). Using chromatin immunoprecipitation sequencing (ChIP-seq), we identified candidate transcriptional regulatory elements of LAIR genes and evaluated their regulatory activity using luciferase reporters. ResultsBoth human and murine macrophages significantly upregulate LAIR1 expression as they differentiate from monocytes to macrophages. In response to interferons, LAIR1 protein levels increase, while LPS causes a relative reduction. Regulatory elements flanking LAIR genes exhibit distinct patterns of enhancer activity with variable responses to immune stimuli. These responses are related to discrete sets of transcription factors in inflammatory pathways that correlate with cell-specific LAIR expression patterns. In addition, we identified LAIR1 and LAIR2 regulatory elements that act as foci of 3D genome interactions with other highly active regulatory elements. ConclusionsOur findings define the complex regulatory landscapes of human and mouse LAIR genes and reveal new insights into the transcriptional regulatory mechanisms that control the expression of these important immune modulatory proteins.

immunology↗