Using flow cytometry, we found that the levels of BCL-XL protein—determined by intracellular staining of BCL-XL—were much higher in TI-Tregs versus PB-Tregs in both human BrCa (Fig. 1c, d) and ccRCC (Fig. 1e, f). The gene discussed is BCL2L1; the disease is nonpapillary renal cell carcinoma.