Malignant melanoma is a prime example of cancers that respond poorly t
o various treatment modalities including chemotherapy(1). A number of
chemotherapeutic agents have been shown recently to act by inducing ap
optosis, a type of cell death antagonized by the bcl-2 gene(2). Human
melanoma expresses Bcl-2 in up to 90% of all cases(3-7). In the presen
t study we demonstrate that bcl-2 antisense oligonucleotide treatment
improves the chemosensitivity of human melanoma grown in severe combin
ed immunodeficient (SCID) mice. Our findings suggest that reduction of
Bcl-2 in melanoma, and possibly also in a variety of other tumors, ma
y be a novel and rational approach to improve chemosensitivity and tre
atment outcome.