In order to generalize and further support the role of mitochondria in edelfosine-induced cell death in Leishmania parasites and tumor cells, L. infantum and HeLa cells stably transfected with the expression vectors pX63-Neo (Leishmania) and pSFFV-Neo (HeLa), containing the human bcl-xL open reading frame (pX63-bcl-xL and pSFFV-bcl-xL, respectively), were used. The gene discussed is BCL2L1; the disease is neoplasm.