[Differentiation therapy of hematologic malignancies: principles, current status and perspectives]

There is increasing evidence that various tumor cells can be induced by differentiation inducers including biological response modifiers, synthetic chemicals and conventional anticancer drugs to differentiate terminally both in vitro and in vivo into cells with normal characteristics. The differentiated cells lose their abilities for proliferation and transplantation in animals. Furthermore, survival times of the animals inoculated with various tumors were found to prolong by administration with the differentiation inducers. These basic findings suggest that induction of terminal tumor cell differentiation is another strategy for cancer therapy: differentiation therapy of cancer. Principles, current status and perspectives of the differentiation therapy of leukemia are reviewed in this article.