Induction of B cell tumor dormancy by anti-idiotypic antibodies.

Long-term dormancy of murine B-cell lymphomas can be experimentally induced by immunizing the host with the idiotype expressed on the tumor. Interaction of the cells with anti-idiotype antibodies is sufficient to induce and maintain the dormant state. The growth of lymphoma cells interacting with anti-idiotype antibodies is arrested and they undergo dramatic changes in their morphology, cell-cycle status and oncogene expression. Regrowth of a tumor after long-term dormancy results from the emergence of a tumor cell variant that no longer responds to the antibodies with growth inhibition. These data demonstrate the feasibility of reversing a malignant phenotype of cells by specific growth arrest signals and suggest new approaches for therapeutic intervention in cancer.