title: The effect of physical training on the N-methyl-N-nitrosourea-induced mammary carcinogenesis of Sprague-Dawley rats.
abstract: The impact of physical activity on carcinogenesis has been demonstrated in many studies. Taking into account the discrepant results of physical exercise on the cell proliferation and apoptosis of breast cancer, we aimed to examine the impact of physical training on N-methyl-N-nitrosourea-(MNU)-induced mammary carcinogenesis. Fifty female rats were divided into four groups according to the intensity of physical activity they undertook. The number of developed tumors, tumor volume, and histopathological diagnoses were noted. Apoptosis and cell proliferation were studied by the number of TUNEL-positive and Ki-67-expressing cells. We demonstrated a statistically significant decrease in the tumor number between all trained groups and the control group. The results were most pronounced in the group with a moderate intensity of training. Moreover, we showed a decrease in tumor volume as training intensity increased, though the differences were not statistically significant. The mean number of TUNEL-positive cancer cells was significantly higher in the training groups than in the control group. These data suggest that physical training, especially of moderate intensity, may alleviate MNU-induced mammary carcinogenesis. The results could suggest that physical exercise-induced apoptosis may be a protective mechanism.
authors.affiliation: Department of Physiotherapy, Wrocław University of Physical Education, Wroclaw 51-612, Poland iwona.malicka@awf.wroc.pl.
authors.forename: Iwona
authors.initials: I
authors.lastname: Malicka
authors.affiliation: Department of Physiotherapy, Wrocław University of Physical Education, Wroclaw 51-612, Poland.
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Siewierska
authors.affiliation: Department of Histology and Embryology, Medical University, Wroclaw 51-612, Poland.
authors.forename: Bartosz
authors.initials: B
authors.lastname: Pula
authors.affiliation: Department of Histology and Embryology, Medical University, Wroclaw 51-612, Poland.
authors.forename: Christopher
authors.initials: C
authors.lastname: Kobierzycki
authors.affiliation: Department of Histology and Embryology, Medical University, Wroclaw 51-612, Poland.
authors.forename: Dominik
authors.initials: D
authors.lastname: Haus
authors.affiliation: Department of Internal Medicine and Clinic of Diseases of Horses, Dogs, and Cats, University of Environmental and Life Sciences, Wroclaw 51-612, Poland.
authors.forename: Urszula
authors.initials: U
authors.lastname: Paslawska
authors.affiliation: Department of Histology and Embryology, Medical University, Wroclaw 51-612, Poland.
authors.forename: Marek
authors.initials: M
authors.lastname: Cegielski
authors.affiliation: Department of Physiotherapy, Wrocław University of Physical Education, Wroclaw 51-612, Poland Department of Histology and Embryology, Medical University, Wroclaw 51-612, Poland.
authors.forename: Piotr
authors.initials: P
authors.lastname: Dziegiel
authors.affiliation: Department of Histology and Embryology, Medical University, Wroclaw 51-612, Poland.
authors.forename: Marzena
authors.initials: M
authors.lastname: Podhorska-Okolow
authors.affiliation: Department of Physiotherapy, Wrocław University of Physical Education, Wroclaw 51-612, Poland.
authors.forename: Marek
authors.initials: M
authors.lastname: Wozniewski
mesh_terms: D000818:Animals; D017209:Apoptosis; D002273:Carcinogens; D049109:Cell Proliferation; D005260:Female; D007150:Immunohistochemistry; D020287:In Situ Nick-End Labeling; D019394:Ki-67 Antigen / Q000378:metabolism; D008325:Mammary Neoplasms, Experimental / Q000139:chemically induced / Q000188:drug therapy / Q000517:prevention & control*; D008770:Methylnitrosourea; D046228:Microarray Analysis; D010805:Physical Conditioning, Animal; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D002273:Carcinogens; D019394:Ki-67 Antigen; D008770:Methylnitrosourea
keywords: Mammary cancer; N-methyl-N-nitrosourea; physical training