Gene expression profile at single cell level from skin of WT and Tsk mice
Patients with systemic sclerosis have a significantly increased incidence of developing various solid malignancies within a few years of systemic sclerosis onset but the mechanism of tumor promotion is not well understood. The tight skin (TSK) mouse has been a valuable model for investigating systemic sclerosis-related pathologies due to increased extracellular matrix deposition, fibrosis in connective tissues, and altered immune cell activation. Despite the role of extracellular matrix and fibrosis in cancer progression, the potential of the TSK mouse as a model for cancer studies is unexplored. Our RNA sequencing analysis of adult dorsal skin samples from TSK and wild-type (WT) mice revealed a notable enrichment for genes typically associated with cancer aggressiveness and desmoplasia. To investigate the impact of the altered microenvironment in TSK mice on cancer progression, we compared the tumor-forming capabilities in TSK mice and WT mice using a syngeneic mouse model of ovarian cancer. TSK mice exhibited larger and more invasive subcutaneous and intraperitoneal tumors in comparison to WT controls, suggesting the role of the microenvironment in promoting cancer progression. Single-cell RNA sequencing analysis of tumors in TSK and WT mice revealed a higher neutrophil-to-lymphocyte ratio, and an enrichment in profibrotic subpopulations of myofibroblasts and macrophages in TSK mice. Overall design: To better understand the differences in cell populations in TSK and WT mice (i.e. subtypes of fibroblasts and specific functional subsets of immune cells), we conducted single-cell RNA sequencing analysis of skin isolated from TSK and WT mice.