Vincristine-resistant P388 leukemia cells contain a large amount of calcium

P388 leukemia cells resistant to vincristine contained more calcium in the cells than the parent sensitive line, especially in the form of EGTA-removable (surface-bound) calcium. Although the relationship, if any, between the high cellular calcium of resistant cells and drug-resistant phenotype is not clear, the possible implications of this result for the elucidation of the mechanisms of drug resistance are interesting.