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 sirolimustreated patients.