Single Nuclei RNA Sequencing of Uterine Serous Carcinoma

Significant racial disparities exist between Black and White patients with uterine serous carcinoma (USC). While the reasons for these disparities are unclear, but several studies have demonstrated significantly distinct rates of driver mutations between racial groups, including TP53. However, limited research has investigated the transcriptional differences of the tumors between these groups, or the composition of the tumor microenvironment (TME) between these groups. Here, we report the findings from the first single nuclei RNA-sequencing experiment conducted on USC tumors. We find that there are significant differences between the tumors of Black and White patients. Tumors exhibited differential expression of specific genes associated with aggressiveness, such as PAX8, and axon guidance and synaptic signaling pathways in Black and White patients. We also demonstrated that differences in T cell and macrophage populations exist between benign and tumor tissues in the TME of USC, as well as between racial groups. Furthermore, we investigated the connection between PAX8 overexpression and immunosuppression in USC through regulation of several cytokines and chemokines. Notably, we show for the first time that PAX8 activity can influence macrophage gene expression and protein secretion. These studies provide a detailed understanding of USC and a basis for using racial information in USC treatment decisions.