CTLA4 and urinary bladder cancer: Although these results could be attributed to the poor binding of this IgG2 anti-CTLA-4 subtype to the human Fc-gamma receptor, accounting for its low predicted ADCC activity, Sharma et al. also report increased frequencies of intratumoral Tregs in on-treatment biopsies of melanoma, bladder cancer and prostate cancer patients treated with the IgG1 anti-CTLA-4 ipilimumab (known to bind to most Fc human receptors), when compared to stage-matched pre-treatment biopsy controls [93].