Immunodetection of myeloid and plasmacytoid dendritic cells in mammary carcinomas of female dogs / Imunodetecção de células dendríticas mieloides e plasmocitoides nos carcinomas mamários em cadelas

Dendritic cells have attracted great interest from researchers as they may be used as targets of tumor immune evasion mechanisms. The main objective of this study was to evaluate the relationship between the dendritic cells (DCs) subpopulation in simple type mammary carcinomas in female dogs. Two groups of samples were used: the control group consisted of 18 samples of mammary tissue without changes and the tumor group with 26 simple type mammary carcinomas. In these groups, we evaluated the immunodetection of immature and mature myeloid DCs, plasmacytoid DCs and MHC-II. In mammary tumor, mature myeloid DCs predominated in the peritumoral region, while immature myeloid DCs and plasmacytoid DCs were evident in the intratumoral region. Immunostaining of MHC-II was visualized in mammary acini (control group), in tumor cells and inflammatory infiltration associated with tumors. The comparison between the control and tumor groups showed a statistically significant difference between immature myeloid DCs, mature myeloid DCs and plasmacytoid DCs. The immunodetection of MHC-II was not significant when comparing the groups. The predominance of immature DCs in the tumor group is possibly related to an inefficient immune response, promoting the development and survival of tumor cells. The presence of plasmacytoid DCs in the same group suggests a worse prognosis for female dogs with mammary tumors. Therefore, the ability of differentiation of canine dendritic cells could be influenced by neoplastic cells and by the tumor microenvironment.(AU)

As células dendríticas têm despertado grande interesse dos pesquisadores, pois podem ser alvo dos mecanismos de evasão imune do tumor. O objetivo principal deste estudo foi avaliar a relação entre as subpopulações de células dendríticas (DCs) nos carcinomas mamários do tipo simples em cadelas. Dois grupos de amostras foram utilizados, o grupo controle composto por 18 amostras de tecido mamário sem alterações e o grupo tumor com 26 carcinomas mamários do tipo simples. Nestes grupos foram avaliadas a imunodetecção de DCs mieloides imaturas e maduras, DCs plasmocitoides e de MHC-II. Nas mamas com tumor, as DCs mieloides maduras predominaram na região peritumoral, enquanto que as DCs mieloides imaturas e as DCs plasmocitoides foram evidentes na região intratumoral. A imunomarcação do MHC-II foi visualizada nos ácinos mamários (grupo controle), nas células tumorais e no infiltrado inflamatório associado aos tumores. Na comparação entre os grupos controle e tumor houve diferença estatística significativa entre as DCs mieloides imaturas, DCs mieloides maduras e DCs plasmocitoides. A imunodetecção de MHC-II não foi significativa na comparação entre os grupos. A predominância de DCs imaturas no grupo tumor, possivelmente, está relacionada com uma resposta imune ineficiente, favorecendo o desenvolvimento e a sobrevivência das células tumorais. A presença das DCs plasmocitoides no mesmo grupo sugere um prognóstico pior para cadelas com tumores de mama. Portanto, a capacidade de diferenciação das células dendríticas caninas poderia ser influenciada pelas células neoplásicas e pelo microambiente tumoral.(AU)

Immunodetection of myeloid and plasmacytoid dendritic cells in mammary carcinomas of female dogs / Imunodetecção de células dendríticas mieloides e plasmocitoides nos carcinomas mamários em cadelas

Dendritic cells have attracted great interest from researchers as they may be used as targets of tumor immune evasion mechanisms. The main objective of this study was to evaluate the relationship between the dendritic cells (DCs) subpopulation in simple type mammary carcinomas in female dogs. Two groups of samples were used: the control group consisted of 18 samples of mammary tissue without changes and the tumor group with 26 simple type mammary carcinomas. In these groups, we evaluated the immunodetection of immature and mature myeloid DCs, plasmacytoid DCs and MHC-II. In mammary tumor, mature myeloid DCs predominated in the peritumoral region, while immature myeloid DCs and plasmacytoid DCs were evident in the intratumoral region. Immunostaining of MHC-II was visualized in mammary acini (control group), in tumor cells and inflammatory infiltration associated with tumors. The comparison between the control and tumor groups showed a statistically significant difference between immature myeloid DCs, mature myeloid DCs and plasmacytoid DCs. The immunodetection of MHC-II was not significant when comparing the groups. The predominance of immature DCs in the tumor group is possibly related to an inefficient immune response, promoting the development and survival of tumor cells. The presence of plasmacytoid DCs in the same group suggests a worse prognosis for female dogs with mammary tumors. Therefore, the ability of differentiation of canine dendritic cells could be influenced by neoplastic cells and by the tumor microenvironment...

As células dendríticas têm despertado grande interesse dos pesquisadores, pois podem ser alvo dos mecanismos de evasão imune do tumor. O objetivo principal deste estudo foi avaliar a relação entre as subpopulações de células dendríticas (DCs) nos carcinomas mamários do tipo simples em cadelas. Dois grupos de amostras foram utilizados, o grupo controle composto por 18 amostras de tecido mamário sem alterações e o grupo tumor com 26 carcinomas mamários do tipo simples. Nestes grupos foram avaliadas a imunodetecção de DCs mieloides imaturas e maduras, DCs plasmocitoides e de MHC-II. Nas mamas com tumor, as DCs mieloides maduras predominaram na região peritumoral, enquanto que as DCs mieloides imaturas e as DCs plasmocitoides foram evidentes na região intratumoral. A imunomarcação do MHC-II foi visualizada nos ácinos mamários (grupo controle), nas células tumorais e no infiltrado inflamatório associado aos tumores. Na comparação entre os grupos controle e tumor houve diferença estatística significativa entre as DCs mieloides imaturas, DCs mieloides maduras e DCs plasmocitoides. A imunodetecção de MHC-II não foi significativa na comparação entre os grupos. A predominância de DCs imaturas no grupo tumor, possivelmente, está relacionada com uma resposta imune ineficiente, favorecendo o desenvolvimento e a sobrevivência das células tumorais. A presença das DCs plasmocitoides no mesmo grupo sugere um prognóstico pior para cadelas com tumores de mama. Portanto, a capacidade de diferenciação das células dendríticas caninas poderia ser influenciada pelas células neoplásicas e pelo microambiente tumoral...

Consensus for the Diagnosis, Prognosis and Treatment of Canine Mammary Tumors

The purpose of this paper is to establish criteria that could guide the diagnosis, prognosis and treatment of canine mammary neoplasias. It was elaborated during the Mammary Pathology Meeting: Diagnosis, Prognosis and Treatment of the Canine Mammary Neoplasm, held on November 6th and 7th, 2010 in Belo Horizonte ­ MG, Brazil, sponsored by the Laboratory of Comparative Pathology ­ UFMG, with the support of the Brazilian Association of Veterinary Pathology (ABPV) and Brazilian Association of Veterinary Oncology (ABROVET). Academics from several regions of Brazil were present and contributed to this work.(AU)