Expression of Bcl-xL and Mcl-1 in the nonmelanoma skin cancers of renal transplant recipients.

OBJECTIVES:This study aims to investigate how immunosuppression influences the protein expression of antiapoptotic members of the Bcl-2 family-namely, Bcl-xL and Mcl-1-in nonmelanoma skin cancer (NMSC) and the peritumoral epidermis of renal transplant recipients. METHODS:NMSC and peritumoral epidermis protein expression of Bcl-xL and Mcl-1 were assessed by immunohistochemistry in renal transplant recipients receiving tacrolimus or sirolimus and the general population not receiving immunosuppression. RESULTS:NMSC from renal transplant recipients compared with patients not receiving immunosuppressant medications had a reduced Bcl-xL expression intensity (P = .042). Mcl-1 expression intensity in NMSC was decreased in tacrolimus-treated patients compared with sirolimus-treated patients and the nonimmunosuppressed population (P = .024). Bcl-xL expression intensity was increased in peritumoral epidermis compared with NMSC (P = .002). CONCLUSIONS:It was shown for the first time that Bcl-xL and Mcl-1 expression are widespread in the peritumoral epidermis and NMSC of renal transplant recipients. Importantly in NMSC, Bcl-xL expression was reduced with immunosuppression exposure, and Mcl-1 expression was reduced in tacrolimus-treated compared with sirolimus-treated patients.