Cancer dormancy: studies of the murine BCL1 lymphoma.

Dormancy in the murine BCL1 lymphoma can be induced by several strategies including cytoreductive therapy of mice with large tumor burdens and challenge of allogeneic chimeric mice or idiotype-immunized mice with BCL1 tumor. Dormant tumor cells were isolated from the spleens of the chimeric mice and the majority were shown to be noncycling. In idiotype-immunized mice that had lost dormancy, tumor growth occurred at a relatively rapid rate. A proportion of idiotype-immunized mice that had lost dormancy spontaneously regressed and then again relapsed; in these mice, the serum antiidiotypic levels were inversely related to the tumor burden.