Kazakova, A. N. | bioRxiv Science

bioRxiv2025

Spatial Transcriptomics Identifies Immune-Stromal Niches Associated with Cancer in Adult Dermatomyositis

Adult-onset dermatomyositis (DM) is an autoimmune inflammatory myopathy with distinct cutaneous manifestations and a strong malignancy association. Through comparative analysis with cutaneous lupus erythematosus (CLE), our integrated spatial and single-cell transcriptomics analysis revealed unique immune and stromal niches associated with DM subtypes. Unexpectedly, we found an association between cancer-associated DM skin lesions and the presence of dispersed immune infiltrates enriched with macrophages, CD8+ T cells, plasma cells, and B cells with preserved vascular architecture. In contrast, non-cancer associated DM skin exhibited dense myeloid cell infiltrates, including neutrophils, monocytes, and macrophages, with elevated expression of IL1B and CXCL10 localized near injured vascular endothelia. Cytokines produced by these myeloid infiltrates together with local tissue hypoxia triggered dramatic stromal remodeling, leading to loss of vascular-associated fibroblasts. In addition to the CXCL10+ myeloid signature, non-cancer-associated DM skin with pDC presence showed the emergence of specific cellular pairs: PD-L1-expressing mregDCs and activated Tregs expressing NFKB2 and TNF receptors. While both DM and CLE showed strong interferon signatures, DM uniquely displayed IFN-{beta} expression. Together, our study provides the first comprehensive spatial mapping of immune and stromal cells in adult-onset DM.

immunology↗

bioRxiv2023

Unlocking DNA Damage Sensitivity of Cancer Cells: The Potential of Splicing Inhibitors

Despite the growing interest in pre-mRNA alternative splicing (AS) as a therapeutic anticancer target, the potential of splicing inhibitors in treating solid tumors remains largely unexplored. We conducted a meta-analysis of transcriptome data from six different tumor types and revealed that splicing inhibitors induced similar patterns of AS, resulting in widespread exon-skipping and intron retention events that often lead to nonsense-mediated decay of the transcripts. Interestingly, in many cases exon skipping is induced by a compensatory cellular response to splicing inhibitor treatment. It involves an upregulation of multiple splicing factors and incomplete recognition of branch points by U2 snRNP. These post transcriptional changes downregulate one-third of essential DNA repair genes, thereby creating a therapeutic vulnerability that can be exploited for cancer treatment. To harness this vulnerability, we proposed a new approach to cancer treatment consisting of sequential addition of a splicing inhibitors followed by a DNA-damaging agent. Our in vitro and in vivo experiments demonstrated that this strategy exhibits promising therapeutic potential for a wide range of tumors.

cancer biology↗