5b:T453,Female transgenic FVB/N mice carrying the breast cancer gene HER-2/neu received epithalon (Ala-Glu-Asp-Gly) in a dose of 1 mg subcutaneously 5 times a week to from the 2nd month of life to death. Epithalon prolonged the average and maximum lifetimes of mice by 13.5 (p<0.05) and 13.9%, respectively. The peptide prolonged the average lifetime of animals without neoplasms (by 34.2%, p<0.05). Epithalon decelerated the development of age-related disturbances in reproductive activity and suppressed the formation of neoplasms. The peptide decreased the incidence of breast adenocarcinomas, lungs metastases (by 1.6 times, p<0.05), and multiple tumors (by 2 times). Epithalon 3.7-fold increased the number of mice without breast tumors (p<0.05), while the number of animals with 6 or more breast tumors decreased by 3 times (p<0.05). Epithalon prolonged the lifetime of mice with breast tumors by 1.4 times (p<0.05). These results indicate that Epithalon possesses geroprotective activity and inhibits breast carcinogenesis in transgenic mice, which is probably related to suppression of HER-2/neu expression.5c:T453,Female transgenic FVB/N mice carrying the breast cancer gene HER-2/neu received epithalon (Ala-Glu-Asp-Gly) in a dose of 1 mg subcutaneously 5 times a week to from the 2nd month of life to death. Epithalon prolonged the average and maximum lifetimes of mice by 13.5 (p<0.05) and 13.9%, respectively. The peptide prolonged the average lifetime of animals without neoplasms (by 34.2%, p<0.05). Epithalon decelerated the development of age-related disturbances in reproductive activity and suppressed the formation of neoplasms. The peptide decreased the incidence of breast adenocarcinomas, lungs metastases (by 1.6 times, p<0.05), and multiple tumors (by 2 times). Epithalon 3.7-fold increased the number of mice without breast tumors (p<0.05), while the number of animals with 6 or more breast tumors decreased by 3 times (p<0.05). Epithalon prolonged the lifetime of mice with breast tumors by 1.4 times (p<0.05). These results indicate that Epithalon possesses geroprotective activity and inhibits breast carcinogenesis in transgenic mice, which is probably related to suppression of HER-2/neu expression.5d:T4c5,The potential preventive effect of the synthetic pineal peptide Epitalon (Ala-Glu-Asp-Gly) on spontaneous tumorigenesis in mice was studied. One-year-old female C3H/He mice were kept for 6.5 months under standard conditions. Epitalon was injected at a dose of 0.1 microg, 5 times a week. Long-term exposure to Epitalon in small doses did not show any toxic effect. Treatment with Epitalon decreased the number of tumor-bearing mice with malignant tumors and prevented the development of metastases. Spontaneous tumors of the reproductive organs (mammary glands and ovaries) were predominant in both groups of mice (control and experimental). The mammary gland tumors were different variants of invasive ductal carcinomas. In the ovaries, granulosa-cell tumors were found. Tumors were in the minority in other organs and had benign characteristics. In control mice, metastases were found in 3 out of 9 tumor-bearing mice, all of them being from tumors of the reproductive organs. Treatment with Epitalon slowed down the development of metastases from spontaneous tumors, and no metastases were found in the experimental mice. These data highlight the antimetastatic effect of Epitalon as part of its oncostatic properties.5e:T80f,