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Published on: May 18, 2020
Prognostic Factors in an Exercised Model of Chemically-induced Mammary Cancer
Antonieta Alvarado1, Ana I Faustino-Rocha2, Rita Ferreira3
1Área de Patología, Decanato de Ciencias Veterinarias, Universidad Centroccidental "Lisandro Alvarado", UCLA, Lara, Venezuela Department of Veterinary Sciences, School of Agrarian and Veterinary Sciences, University of Trás-os-Montes and Alto Douro, UTAD, Vila Real, Portugal Center for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB), UTAD, Vila Real, Portugal.
Background/Aim:
Estrogen receptor α (ERα) and Ki-67 are strong prognostic and predictive markers in woman breast cancer. This study aimed to evaluate the immunoexpression of prognostic factor markers ERα, Ki-67 proliferation index (Ki-67 PI) and the mitotic activity index (MAI) in mammary tumors induced by 1-methyl-1-nitrosourea (MNU) in female Sprague-Dawley rats submitted to lifelong exercise training.
Materials And Methods:
Thirty female rats were injected with MNU and randomly divided into two groups: sedentary and exercised.
Results:
All neoplasms from both groups were ERα-positive with an H-score ≥20. Statistically significant differences were not found in the ERα H-score, Ki-67 PI and MAI between groups. The absolute value of ERα H-score was higher in the exercised group, while the Ki-67 PI and MAI were higher in the sedentary group.
Conclusion:
Tumors from the exercised group were less proliferative and more differentiated, suggesting that long-term exercise training had positive effects on mammary carcinogenesis.
