Mast Cells in Mammary Carcinogenesis: Host or Tumor Supporters?
The effects of mast cells on carcinogenesis is not yet fully understood. This work aimed to disclose the role of mast cells in mammary carcinogenesis in a rat model.



Mammary tumors were induced by the administration of N-methyl-N-nitrosourea (MNU) in three groups of rats. Animals from one group were treated with ketotifen immediately after MNU administration, and animals from another only received ketotifen after the development of the first mammary tumor. The biochemical profile was determined. Mammary tumors were evaluated by histopathology and immunohistochemistry.



Animals from ketotifen-treated groups developed fewer mammary tumors, higher number of mammary lesions and had lower histamine levels when compared to non-treated animals. Animals treated with ketotifen immediately after MNU exhibited the lowest proliferative and apoptotic indexes.



The mainly positive effect of the inhibition of mast cell degranulation seems to be the reduction of tumor proliferation when the mast cell degranulation was inhibited before tumor development.
Department of Veterinary Sciences, School of Agrarian and Veterinary Sciences, University of Trás-os-Montes and Alto Douro, Vila Real, Portugal anafaustino.faustino@sapo.pt.|Center for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB), University of Trás-os-Montes and Alto Douro, Vila Real, Portugal.|Animal and Veterinary Research Center (CECAV), School of Agrarian and Veterinary Sciences, University of Trás-os-Montes and Alto Douro, Vila Real, Portugal.|Organic Chemistry, Natural Products and Foodstuffs (QOPNA), Mass Spectrometry Center, Department of Chemistry, University of Aveiro, Aveiro, Portugal.
Ana I
AI
Faustino-Rocha
Department of Veterinary Sciences, School of Agrarian and Veterinary Sciences, University of Trás-os-Montes and Alto Douro, Vila Real, Portugal.|Animal and Veterinary Research Center (CECAV), School of Agrarian and Veterinary Sciences, University of Trás-os-Montes and Alto Douro, Vila Real, Portugal.
Adelina
A
Gama
Advanced Polytechnic and University Cooperative (CESPU), Institute of Research and Advanced Training in Health Sciences and Technologies (IINFACTS), Gandra, Portugal.|Research Center in Physical Activity, Health and Leisure (CIAFEL), Faculty of Sports, University of Porto, Porto, Portugal.
Maria J
MJ
Neuparth
Department of Veterinary Sciences, School of Agrarian and Veterinary Sciences, University of Trás-os-Montes and Alto Douro, Vila Real, Portugal.|Center for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB), University of Trás-os-Montes and Alto Douro, Vila Real, Portugal.
Paula A
PA
Oliveira
Organic Chemistry, Natural Products and Foodstuffs (QOPNA), Mass Spectrometry Center, Department of Chemistry, University of Aveiro, Aveiro, Portugal.
Rita
R
Ferreira
Department of Veterinary Sciences, School of Agrarian and Veterinary Sciences, University of Trás-os-Montes and Alto Douro, Vila Real, Portugal.|Center for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB), University of Trás-os-Montes and Alto Douro, Vila Real, Portugal.
Mário
M
Ginja
D000818:Animals; D049109:Cell Proliferation; D002471:Cell Transformation, Neoplastic; D005260:Female; D007150:Immunohistochemistry; D007665:Ketotifen / Q000737:chemistry; D015674:Mammary Neoplasms, Animal / Q000139:chemically induced / Q000503:physiopathology*; D008325:Mammary Neoplasms, Experimental / Q000139:chemically induced / Q000503:physiopathology*; D008407:Mast Cells / Q000166:cytology*; D008770:Methylnitrosourea / Q000737:chemistry; D051381:Rats; D017207:Rats, Sprague-Dawley
D008770:Methylnitrosourea; D007665:Ketotifen
Degranulation; MNU; ketotifen; mammary tumors; mast cells; rat