In scRNA-seq cohorts (GSE264573 and an independent CRPC cohort), malignant epithelial cells were inferred by copy-number alteration profiles, EZH2^high versus EZH2^low malignant programs were characterized, T-cell subsets were quantified, and tumor-Treg communication was inferred using CellPhoneDB as hypothesis-generating predictions. The gene discussed is EZH2; the disease is neoplasm.