Growth inhibition of Lewis lung carcinoma by an inorganic dye, Ruthenium Red.

The growth of subcutaneously transplanted Lewis lung carcinoma in BDF1 mice was inhibited by an inorganic dye, Ruthenium Red. The mean volume of the tumors of the mice which were given Ruthenium Red by daily ip injection of 5 mg/kg on days 1 approximately 10 was 28 and 39% of that of the controls at days 18 and 23 after transplantation, respectively. The median survival time (MST) of the treated mice was 27.8 days while that of the control was 23.0 days. The higher MST (32.5 days) was obtained when the dye was given at 2.5 mg/kg for 1 approximately 20 days, although the tumor volume in this group of mice was 51% of that of the control at day 18.