Fereshte Ghandehari - Department of Microbiology, Falavarjan Branch, Islamic Azad University, Isfahan, Iran
Mahnoosh Fatemi - Department of Biology, Falavarjan Branch, Islamic Azad University, Isfahan, Iran

Background and aims: Antimicrobial peptides constitute a family of bioactive peptides that are involved in the body defense. Recently,their anti-cancer properties, especially by inducing apoptosis, have been proven in in vitro studies. Therefore, in this study, the effects ofcecropin B as an antimicrobial peptide on breast cancer growth, hematological parameters, and histopathological changes in rats wereevaluated.Methods: Twenty-four female rats were randomly divided into ۴ groups. The cancer group, control group, cecropin B group, and cancergroup treated with cecropin B. The tumor size was measured at the beginning and the completion of the treatment period. Blood sampleswere collected for assessment of the hematological parameters and Bax and Bcl۲ levels. Tumor tissues were removed for histopathologicalanalysis.Results: The tumor size had a significant increase in the cancer group and cancer group treated with cecropin at the end of the treatment.A significant decrease in mean cell volume, white blood cell count and Bcl۲ level and a significant increase in hemoglobin and Bax levelswere observed in the cancer group treated with cecropin B compared to cancer group. Changes in other parameters were not significant.Histopathological study showed the invasion of mitotic cells to stromal and muscular tissues of the breast in the cancer group, while focaldestruction of tissue and cell death were observed in the cancer group treated with cecropin B.Conclusion: The results showed that cecropin B has been able to reduce tumor growth and have little side effects on hematologic factorsprobably through apoptosis.

Cecropin B, Apoptosis, Breast cancer, Hematological parameters