Antitumor activity of calcium in combination with antitumor agents against Lewis lung carcinoma.

The antitumor activity of calcium gluconate in combination with mitomycin C and 5-fluorouracil was examined against subcutaneously implanted Lewis lung carcinoma-bearing C57BL/6 mice. The mice were divided into four groups: group 1 received mitomycin C (2 mg/kg) and 5-fluorouracil (50 mg/kg) intraperitoneally once a week for four weeks beginning from the day after implantation of tumors, as well as calcium gluconate (155 mg/kg) twice a week for the same four weeks; group 2 received only mitomycin C and 5-fluorouracil; group 3 received only calcium gluconate; group 4 received a vehicle (physiological saline). Significantly enhanced inhibition of tumor growth was observed neither in a comparison between groups 3 and 4, nor in a comparison between groups 1 and 2 (expect on day 20 post implantation). Thus calcium gluconate given alone or in combination with antitumor agents hardly appeared to possess effective antitumor activity.