Titration of the effects of a group of selected chemicals on the growth of ascites and solid forms of the Nelson mouse tumor.

Effects of twenty-seven chemicals on the growth of Nelson mouse tumor have been studied. The solid and ascites forms of the tumor were treated with graded doses of chemicals. Results of the treatment of both forms of the tumor showed an absence of a strict correlation between the effects of chemicals on this tumor and their recognized clinical usefulness. Cytoxan, hydrocortisone, 5-fluorodeoxyuridine, and N-methyl-formamide were found to be the most effective chemicals against the solid Nelson tumor, and HN2, TEM, actinomycin C and Amethopterin showed no tumor-specific effects. The ascites form was found to be very sensitive to treatment with the majority of tested chemicals. Four chemicals effective against the solid form also inhibited the ascites form to the greatest extent. In addition to these, nine other chemicals inhibited growth of the ascites tumor by more than 75 per cent. Semistarvation of tumor-bearing mice caused complete growth inhibition of the ascites form of Nelson tumor and inhibited the growth of the solid form by half.