We identified 10 published studies with ccRCC scRNA-seq data, of which only 5 included cells likely to be ECs that were defined by measurable coexpression of PECAM1 and CDH5. None of the prior studies specifically enriched for ECs, resulting in an average of 217 ECs/sample (range 2–518/cells sample, Table S4). Here, PECAM1 is linked to nonpapillary renal cell carcinoma.