Aaam. Danenvanoorschot et al., APOPTIN INDUCES APOPTOSIS IN HUMAN TRANSFORMED AND MALIGNANT-CELLS BUT NOT IN NORMAL-CELLS, Proceedings of the National Academy of Sciences of the United Statesof America, 94(11), 1997, pp. 5843-5847
The chicken anemia virus protein apoptin induces a p53-independent, Bc
l-2-insensitive type of apoptosis in various human tumor cells. Here,
we show that, in vitro, apoptin fails to induce programmed cell death
in normal lymphoid, dermal, epidermal, endothelial, and smooth-muscle
cells, However, when normal cells are transformed they become suscepti
ble to apoptosis by apoptin. Long-term expression of apoptin in normal
human fibroblasts revealed that apoptin has no toxic or transforming
activity in these cells, In normal cells, apoptin was found predominan
tly in the cytoplasm, whereas in transformed and malignant cells it wa
s located in the nucleus, suggesting that the localization of apoptin
is related to its activity, These properties make apoptin a potential
agent for the treatment of a large number of tumors, also those lackin
g p53 and/or overexpressing Bcl-2.