UC Berkeley

Cryosurgery employs freezing to destroy solid tumours. However, frozen cells can survive and cause cancer recurrence. Bleomycin, an anticancer drug with a huge intrinsic cytotoxicity is normally not very effective because it is nonpermeant. We report that freezing facilitates bleomycin penetration into cells making it toxic to cryosurgery surviving cells at concentrations that are non-toxic systemically.