Purpose Metastasis represents the major cause of deaths in cancer patients, and the tumor surrounding extracellular matrix (ECM) passes through changes in its organization during the evolution of this process. Therefore, the aim of the present study was to quantify the deposition of proteins that constitute the ECM, namely total collagen, collagen I (Col I) and collagen III (Col III) in samples from patients with metastatic (mPCa) and non-metastatic prostate cancer (PCa), in addition of evaluating the basement membrane integrity. Methods Tissue samples from 60 patients were divided into three groups according to parameters ISUP grade, TNM staging and PSA concentration: better prognosis (n = 20), worse prognosis (n = 23) and metastatic (n = 17). To quantify collagen, the Picrosirius Red technique was used with further analysis under a polarization microscope, and to basement membrane analysis the Periodic Acid Schiff (PAS) technique was employed, where the coloring was classified in G1, G2 and G3. Results It was observed that the Col I/ Col III ratio was higher in the metastatic group in relation to better prognosis (p = 0.012) and worse prognosis (p = 0.018) groups. About the basement integrity, it was observed that its constitution in the malignant tumor tissue differed from the adjacent non-tumor tissue (p = 0.000). Also, the worsening in the tumor tissue integrity was positively correlated with worse prognosis parameters (advanced ISUP grade, extraprostatic extension and perineural invasion). Conclusion Our study indicates that the absence of Col III can constitute a marker for potential metastatic tumors. The basement membrane integrity also seems to be an indicator of poor prognosis in malignant prostatic tumors.

Prostate cancer (PCa) lacks speci c markers capable of distinguishing aggressive tumors from those with indolent behavior. Therefore, the aim of this study was to evaluate the immunostaining of four candidate proteins (PTEN, AKT, TRPM8, and NKX3.1) through the immunohistochemistry technique (IHC), in tissues from patients with metastatic and non-metastatic PCa. Tissues from 60 patients were divided into three groups categorized according to prognostic parameters: better prognosis (n=21), worse prognosis (n=22), and metastatic (n=17). Immunostaining was analyzed by a pathologist and staining classi cations were considered according to signal intensity: (0) no staining, (+) weak, and (++ and +++) intermediate to strong. AKT protein was independently associated with the presence of extraprostatic extension (p=0.012; OR=0.050; 95% CI=0.005-0.524). The immunostaining for TRPM8 (p=0.005) and NKX3.1 proteins (p<0.001) differed between malignant tumor and adjacent tissue as well as for proteins cellular location (nucleus and cytoplasm).NKX3.1 showed positive and predominantly strong immunostaining in all patients, in both tumoral and adjacent tissues. The staining in the prognostic groups showed that all metastatic samples had a positive immunostaining, with strong intensity for NKX3.1 (p=0.035). In the non-metastatic group, this strong protein staining was not observed in any patients. This study con rmed that the NKX3.1 protein is highly speci c for prostate tissue and indicated that NKX3.1, AKT and TRPM8 may be prognostic markers for prostate cancer.

Introdução: O câncer de próstata (CaP) é o segundo tipo de câncer mais comum em homens e a quinta causa de morte no mundo. A triagem para o rastreamento do CaP consiste no toque digital retal e na quantificação do PSA (antígeno prostático específico). Porém, esses métodos são incapazes de diferenciar tumores indolentes e doenças prostáticas benignas do adenocarcinoma maligno. Portanto, buscam-se maneiras alternativas de fazer um diagnóstico mais preciso e menos invasivo. Objetivos: Dentro deste contexto, este trabalho avaliou a imunomarcação tecidual do Homólogo de Fosfatase e Tensina (PTEN) e Serina/Treonina Quinase (AKT) pertencentes a uma importante via de sobrevivência celular alterada em diversos tumores malignos humanos. Material e Métodos: Trabalho aprovado pelo Comitê de Ética em Pesquisa Envolvendo Seres Humanos/UEL, parecer 176/2013. As proteínas foram avaliadas através da técnica de imunohistoquímica (IHQ) indireta considerando os tecidos prostáticos tumoral e não tumoral adjacente de 60 pacientes, divididos em três grupos categorizados através de parâmetros prognósticos: melhor prognóstico (n=21), pior prognóstico (n=22) e metastático (n=17). A imunomarcação foi analisada por patologista e as classificações de coloração foram consideradas segundo a intensidade do sinal: (0) ausência de marcação, (+) fraca e (++) intermediária à forte. Para todas as análises foi utilizado o software IBM® SPSS® Statistics for Windows, version 20.0. Resultados: Verificou-se que a média de idade dos pacientes foi 64,4±4,6 (melhor prognóstico), 67,6±5,7 (pior prognóstico) e 71,4±10,1 (metastático), com diferença entre os grupos de melhor prognóstico e metastático (p=0,008) e entre os grupos não metastático e metastático (p=0,010). Na análise de interação, verificou-se que PTEN e AKT (p<0,001) estavam significativamente correlacionadas. No entanto, mostraram uma imunomarcação fraca ou ausente em praticamente todas as amostras do presente estudo e não demonstraram associações significativas nem em relação aos tecidos tumoral e não tumoral adjacente e nem em relação aos parâmetros prognósticos ou aos processos de recidiva e metástase. Conclusão: Este estudo indicou que as proteínas PTEN e AKT, apesar de apresentarem interação proteica significativa, não demonstraram potencial de biomarcadores para o CaP, devido à ausência de associação significativa com grupos de prognóstico, parâmetros prognósticos ou com os processos de recidiva e/ou metástase.

Prostate cancer (PCa) lacks specific markers capable of distinguishing aggressive tumors from those with indolent behavior. Therefore, the aim of this study was to evaluate the immunostaining of four candidate proteins (PTEN, AKT, TRPM8, and NKX3.1) through the immunohistochemistry technique (IHC), in tissues from patients with metastatic and non-metastatic PCa. Tissues from 60 patients were divided into three groups categorized according to prognostic parameters: better prognosis (n=21), worse prognosis (n=22), and metastatic (n=17). Immunostaining was analyzed by a pathologist and staining classifications were considered according to signal intensity: (0) no staining, (+) weak, and (++ and +++) intermediate to strong. AKT protein was independently associated with the presence of extraprostatic extension (p=0.012; OR=0.050; 95% CI=0.005-0.524). The immunostaining for TRPM8 (p=0.005) and NKX3.1 proteins (p<0.001) differed between malignant tumor and adjacent tissue as well as for proteins cellular location (nucleus and cytoplasm). NKX3.1 showed positive and predominantly strong immunostaining in all patients, in both tumoral and adjacent tissues. The staining in the prognostic groups showed that all metastatic samples had a positive immunostaining, with strong intensity for NKX3.1 (p=0.035). In the non-metastatic group, this strong protein staining was not observed in any patients. This study confirmed that the NKX3.1 protein is highly specific for prostate tissue and indicated that NKX3.1, AKT and TRPM8 may be prognostic markers for prostate cancer.