PEF1 and neoplasm: The following mice groups were used in the study: (1) untreated tumor- bearing mice (CTRL); (2) tumor-bearing mice treated with CaCl2 (CTRL+Ca); (3) treated with PEF1; (4) treated with PEF2; (5) treated with PEF1 + CaCl2 (PEF1+Ca); (6) treated with PEF2 + CaCl2 (PEF2 + Ca).