Expresión Inmunohistoquímica de Ki-67 en Lesión Central de Células Gigantes / Immunohistochemical Expression of Ki-67 in Central Giant Cell Lesion

RESUMEN: La lesión central de células gigantes (LCCG) es una lesión osteolítica benigna que en algunos casos presenta un comportamiento agresivo, con recidiva y mal pronóstico. Ki-67 es una proteína nuclear cuya función general es la regulación de la proliferación celular. Este marcador es utilizado para el reconocimiento de células en proliferación y como herramienta de pronóstico en el diagnóstico de neoplasias. El objetivo de este estudio fue cuantificar la inmunoexpresión de Ki-67 en las diferentes poblaciones celulares de las LCCG y analizar su asociación con las características clínicas, demográficas y radiográficas. Se evaluó la inmunoexpresión de Ki-67 de 17 casos de LCCG en dos poblaciones celulares: células gigantes multinucleadas (CGM) y células mesenquimatosas estromales (CME). El análisis estadístico se efectuó con el programa SAS 9.0 y SPSS versión 23.0, con un nivel alfa impuesto de P<0,05. Las CME mostraron inmunoexpresión promedio de 9,4 % y las CGM de 0,65 %. No se encontró relación estadísticamente significativa entre las características clínicas, demográficas y radiográficas de las LCCG y la inmunoexpresión de Ki-67. La expresión de Ki-67 en CME sugiere que esta población se encuentra en constante actividad celular y que las LCCG son lesiones dinámicas y en constante proceso de diferenciación.

ABSTRACT: The central giant cell lesion (CGCL) is a benign osteolytic lesion which in some cases presents an aggressive behavior with recurrence and poor prognosis. Ki67 is a nuclear protein whose general function is the regulation of cell proliferation. This marker is used to identify proliferating cells and as a prognostic tool in the diagnosis of neoplasms. The aim of this study was to quantify the immune expression of Ki-67 in the different cell populations of CGCL and analyze its association with clinical, demographic and radiographic characteristics. The Ki-67 immune expression of 17 cases of LCCG was evaluated in two cell populations: multinucleated giant cells (CGM) and stromal mesenchymal cells (SMC). The statistical analysis was carried out with SAS 9.0 and SPSS version 23.0, with an alpha tax level of P <0.05. The CME showed average immune expression of 9.4 % and the CGM of 0.65 %. No statistically significant relationship was found between the clinical, demographic and radiographic characteristics of the CGCL and the immune expression of Ki-67. The expression of Ki-67 in CME suggests that this population is in constant cellular activity, and that the CGCL are dynamic lesions in a continuous differentiation process.

Association between decreased expression of estrogen receptor alpha, androgen receptor and phosphatase and tensin homolog immunoexpression in the canine prostate / Associação entre diminuição da expressão dos receptores de estrógeno alfa e andrógeno, e imunoexpressão de fosfatase e tensina homóloga na próstata canina

Canine prostate gland is a hormonal dependent organ and its imbalance of estrogen and androgen receptor expressions are directly associated with the development of different diseases. Due to the lack of information regarding the behavior of the aforementioned receptors in canine prostate cancer (PC), this study aimed to identify estrogen receptor alpha (ERα), androgen receptor (AR), Ki67 and phosphatase and tensin homolog (PTEN) protein expressions in canine PC by immunohistochemistry. We found nuclear expression of ERα and AR in the epithelial cells of normal canine samples and a loss of protein expression in PC samples. Normal samples showed Ki67 expression in a few basal cells and the PC samples showed the highest mean of positive cells (253.1). Canine prostate cancer showed a high proliferative index, which was associated with independence of hormonal actuation. PTEN showed positive nuclear and cytoplasmic expression in normal canine samples and a loss in PC. Loss of ERα, AR and PTEN indicated that canine PC exhibits the same immunohistochemical phenotype as in human patients with PC resistant to hormonal therapy. Therefore, canine PC should be considered as a model to study human PC resistant to hormonal therapy.(AU)

A glândula prostática canina é um órgão dependente de hormônio, e o desequilíbrio na expressão dos receptores de estrógeno e andrógeno estão diretamente associados com o desenvolvimento de diferentes doenças. Devido à falta de informação sobre o comportamento desses receptores no câncer prostático canino (PC), este estudo tem por objetivo identificar a expressão proteica através da técnica de imuno-histoquímica do receptor de estrógeno alfa (REα), receptor de andrógeno (RA), Ki67 e fosfatase e tensina homóloga (PTEN). Foi encontrado nas células epiteliais prostáticas normais caninas a expressão nuclear de REα e RA, e perda de expressão proteica nas amostras de PC. As amostras normais apresentaram expressão de Ki67 em poucas células basais e as amostras de PC apresentaram a maior média de células positivas (253,1). O câncer de próstata canino apresentou uma taxa alta de proliferação, o qual foi associado com a atuação independente de hormônio. As amostras de próstatas caninas normais revelaram marcação nuclear e citoplasmática da proteína PTEN e perda nas amostras de PC. A perda de REα, RA e PTEN indicam que as amostras de PC exibem o mesmo fenótipo imuno-histoquímico de pacientes humanos com câncer prostático resistente a terapia hormonal. Sendo assim, o PC canino deve ser considerado um modelo para estudos de câncer prostático humano resistente a terapia hormonal.(AU)

Correlation of p16INK4a immunoexpression and human papillomavirus (HPV) detected by in-situ hybridization in cervical squamous neoplasia

Persistence and eventual integration of high-risk HPV (hrHPV) into the cervical cell is crucial to the progression of cervical neoplasia and it would be beneficial to morphologically identify this transformation in routine surgical pathology practice. Increased p16INK4a (p16) expression is a downstream event following HPV E7 binding to pRB. A study was conducted to assess the correlation between hrHPV detection using a commercial in-situ hybridization assay (Ventana INFORM HPV ISH) and p16 immunoexpression (CINtec Histology Kit) in cervical squamous intraepithelial lesions and squamous carcinoma. 27 formalin-fixed, paraffin-embedded cervical low-grade squamous intraepithelial lesions (LSIL), 21 high-grade squamous intraepithelial lesions (HSIL) and 51 squamous carcinoma (SCC) were interrogated. hrHPV was significantly more frequent in HSIL (76.2%) and SCC (88.2%) compared to LSIL(37.0%). p16 expression was similarly more frequent in HSIL (95.2%) and SCC (90.2%) compared to LSIL(3.7%). That the rates of hrHPV when compared with p16 expression were almost equivalent in HSIL and SCC while p16 was expressed in only 1 of the 10 LSIL with hrHPV, are expected considering the likelihood that transformation has occurred in HSIL and SCC but does not occur in majority of LSIL.

Expression of galectin-3 in gastric adenocarcinoma.

Background & objectives: Galectin-3 a member of the galectin family is an endogenous β-galactoside binding lectin. It has been found to be associated with cell adhesion, recognition, proliferation, differentiation, immunomodulation, angiogenesis, apoptosis and can be a reliable marker for cancer aggressiveness. The aim of this study was to verify protein expression in gastric adenocarcinoma tissues and correlate the results with the clinical aspects in the study population. Methods: Galectin-3 expression was examined by immunohistochemistry in 57 samples of gastric adenocarcinomas tissues. Galectin-3 protein expression was observed in the cytoplasm and the nucleus of examined tissues. Results: Thirty one (54.4%) samples had strong or moderate staining and 26 (45.6%) tumours had negative or weak staining. The galectin-3 did not show association with the sex (p=0.347), age (p=0.999), Lauren’s classification (p=0.731) and TNM stage (p=0.222). Regarding the TNM stage, 66.7 per cent of stage I tumours had strong or moderate staining; with tumours stage IV this percentage was 33.3 per cent. Interpretation & conclusion: Our results suggest that gal-3 is not a reliable biomarker for prognosis of the gastric adenocarcinoma by immunohistochemistry. Further studies need to be done on a large sample of tumour tissues in different clinical staging