Mitochondrial therapy can inhibit melanoma development.

e21571 Background: Mitochondria of tumor cells undergo adaptive changes for even more active reproduction of tumor cells in the acidic and hypoxic microenvironment of tumor tissue. The purpose of this study was to evaluate antitumor effect of mitochondrial therapy in BALB/c Nude mice of both genders with B16/F10 melanoma growth. Methods: Male (n = 10) and female (n = 10) BALB/c Nude mice were injected subcutaneously with 0.5 ml of a suspension of B16/F10 mouse melanoma tumor cells in saline at a dilution of 1:20. Mitochondria (MC) were isolated from rat liver. 24 hours after subcutaneous transplantation of B16/F10 melanoma, mice were intraperitoneally injected with freshly isolated mitochondria (3.3 mg of protein per animal in 0.3 ml of saline). Further, mitochondrial therapy (MC therapy) was carried out according to the scheme on days 3, 5, 9, 13, 16, 19, 21. Male BALB/c Nude mice with subcutaneous inoculation of B16/F10 melanoma receiving intraperitoneal injections with 0.3 ml of saline served as controls. Results: Subcutaneous tumors in mice of both genders could be determined on the 5th day from the moment of tumor transplantation. In males, the regressive effect of MC therapy was recorded from the 8th day of tumor growth. The average tumor volume in males with MC therapy on day 8 was 3.0 times less than in the control group. On days 12 and 15, the regressive difference in tumor volumes between the groups was 1.8 times (p < 0.05) (MC therapy). On day 19, a slower tumor growth was recorded in the group with MC therapy, where the tumor volume was 2 times lower compared to the control volumes. At the end of the experiment on day 22, the difference in the average tumor volumes was 3.2 times, i.e. a significant inhibition of tumor growth was determined in males treated with MC therapy. A sizeable tumor node in females treated with MC therapy formed longer than in males, remaining as a flat tumor spot for up to 8 days. The inhibition of the growth of a large tumor node was determined on day 12 of melanoma growth, and the difference with the control values was 1.8 times (p < 0.05). On day 15, the tumor volumes in females with MC therapy decreased by 2.2 times compared with the control values, on day 19 - by 2.1 times. As a result, by the end of the experiment (day 22), the difference with the control group was 2.7 times. Conclusions: MC therapy inhibits the growth of B16/F10 melanoma in male and female BALB/c Nude mice. Formation of a sizeable tumor node and the start the tumor growth inhibition differs in time depending on the gender of experimental animals.