PTEN loss in Gleason grade 7 prostate tumors exhibits intratumoral heterogeneity and is associated with unfavorable pathological features

Background: PTEN loss is observed in 20­30% of prostate cancers and is associated with a poor outcome, but clinical details of the impact of this biomarker are unclear for intermediate grade tumors. Methods: We investigated 43 radical prostatectomy-derived grade 7 prostate tumors from the Clinics Hospital of Ribeirão Preto. Tissue microarray (TMA) blocks were constructed and PTEN copy number status was determined for all patients through fluorescence in situ hybridization (FISH). To determine the presence of PTEN protein loss in our study cohort, we performed immunohistochemistry (IHC) in TMA sections. We then developed an automated algorithm in HALO™ to identify regions of PTEN protein loss in whole prostate scanned sections from ten patients with known PTEN deletion status by FISH. Clinical analyses were conducted to determine the associations between PTEN loss and patient outcome. All statistical analyses were conducted in R v3.4.3 with P-values below 0.05 being considered statistically significant. Results: In this study of 43 grade 7 tumors, we found PTEN deletions by FISH in 18.9% of tumors, and PTEN protein loss by IHC in 16.3% of tumors. Both techniques were highly concordant and complementary. Clinical analysis demonstrated that PTEN deletion by FISH was significantly associated with positive margin invasion (P = 0.04) and Gleason score upgrade (P = 0.001). Digital image analysis of ten representative tumors demonstrated distinct intratumoral heterogeneity for PTEN protein loss in four tumors. Conclusions: This study shows that PTEN loss in Gleason grade 7 tumors can be heterogeneous and that a systematic analysis of this biomarker using a combination of FISH, IHC, and digital imaging may identify patients with a greater risk of poor outcome (AU)

Immunohistochemistry analysis of proteins related with apoptosis as prognostic factor in epidermoid carcinomaof penis / Análisis inmunohistoquímico de proteínas relacionadas con la apoptosis como factor pronóstico en el carcinoma epidermoide de pene

The aim was to analyze the protein expression of apoptotic genes caspase-3, caspase-8 and bcl-2 with the immunohistochemistry technique, correlating with tumor grade (I, II and III) and with the patient survival in order to understand the basic mechanism of tumoral transformation. The immunohistochemistry reactions on 50 samples of squamous cell carcinoma were carried out with the avidin-biotin immunoperoxidase method and antigen recovery. The analyses were made using the graduation method "in crosses" (0 to 4 crosses - no stain to more than 75 percent of positives cells) and in categories (low, intermediate, high) of the cytoplasm immunoreactivity of the epidermoid penile carcinoma cells. It was observed a statistically significant difference when the expression of caspase-3 were compared with the grades I and II of the tumor (p=0.0010) and when comparing the patient survival with the grades I and II of the tumor (p=0.0212). The protein bcl-2 was more expressed than caspase-3 and caspase-8 proteins, suggesting that the apoptotic rate in this carcinoma is low. The higher expression of the anti-apoptotic protein bcl-2 suggests a higher preservation of the tumoral cells...

El objetivo fue analizar la expresión de las proteínas de genes de apoptosis caspasa-3, caspasa-8 y Bcl-2-con la técnica de inmunohistoquímica, en correlación con el grado tumoral (I, II y III) y la supervivencia del paciente con el fin de comprender el mecanismo básico de la transformación tumoral. Se analizaron las reacciones inmunohistoquímicas sobre 50 muestras de carcinoma de células escamosas mediante el método de la inmunoperoxidasa avidina-biotina y la recuperación de antígeno. Los análisis se realizaron utilizando el método de graduación "en cruces" (0 a 4 cruces - no tinción a más del 75 por ciento de las células positivas) y en categorías (baja, media, alta) de la inmunorreactividad citoplasmática de las células de carcinoma epidermoide de pene. Se observó una diferencia estadísticamente significativa cuando la expresión de la caspasa-3 se comparó con los grados I y II del tumor (p = 0,0010) y cuando se comparan la supervivencia de los pacientes con los grados I y II del tumor (p = 0,0212). La proteína bcl-2 se expresa más que la caspasa-3 y caspasa-8, lo que sugiere que la tasa de apoptosis en este carcinoma es baja. La mayor expresión de la proteína anti-apoptótica bcl-2 sugiere una mayor preservación de las células tumorales...