Análise imuno-histoquímica da Yes-Associated Protein (YAP) e sua influência sobre a proliferação celular e a apoptose em lesões odontogênicas epiteliais benignas / Immunohistochemical analysis of Yes-Associated Protein (YAP) and its influence on cell proliferation and apoptosis in benign epithelial odontogenic lesions

Introdução: Os cistos e tumores odontogênicos são lesões que apresentam comportamento biológico heterogêneo e patogênese ainda não totalmente esclarecida. A Yes-associated protein (YAP) atua como um regulador transcricional de genes envolvidos na proliferação celular e na apoptose, participando da ativação de vias associadas ao crescimento cístico e à progressão neoplásica. Objetivo: Analisar a expressão imuno-histoquímica da proteína YAP e correlacioná-la com marcadores envolvidos na proliferação celular e na apoptose em lesões odontogênicas epiteliais benignas. Metodologia: A amostra consistiu de 95 casos de lesões odontogênicas - 25 cistos dentígeros (CDs), 30 CO não sindrômicos (COs), 30 AMB convencionais (AMB-Cs) e 10 AMB unicísticos (AMB-Us) -, além de 10 espécimes de folículo dentários (FD). Foi realizada coleta dos dados clinico-demográficos dos casos, bem como análise morfológica para melhor caracterização da amostra. Os cortes histológicos foram submetidos à técnica imuno-histoquímica através da utilização dos anticorpos YAP, ciclina D1, Ki-67 e Bcl-2, e a análise da expressão destes foi realizada quali-quantitativamente, mediante metodologia adaptada. Os dados coletados seguiram para análise descritiva e estatística (p ≤ 0,05). Resultados: Houve discreta predileção por mulheres (n = 55; 57,6%) e por indivíduos na faixa etária dos 21 aos 40 anos (n = 50; 47,6%), sendo a região posterior de mandíbula mais afetada (64%). A análise da imunoexpressão de YAP revelou maiores níveis de expressão em COs, especialmente nas camadas basal e parabasal, seguido dos AMB-Us e AMB-Cs, que demonstraram moderada imunorreatividade, predominantemente nas células periféricas. Além disso, houve diferenças significativas quanto à imunoexpressão de YAP entre os grupos analisados, com existência de correlações positivas e estatisticamente significativas entre YAP e ciclina D1 em CDs e AMB-Us, e entre YAP e Ki-67 em AMB-Us (p < 0,05). Todavia, entre a imunoexpressão YAP e Bcl-2, foi verificada ausência de correlação estatisticamente significativa. Conclusões: A YAP pode exercer influência sobre a proliferação celular do epitélio de cistos e tumores odontogênicos, auxiliando, assim, na progressão das diferentes lesões odontogênicas (AU).

Background: Odontogenic cysts and tumors present heterogeneous biological behavior, and their etiopathogenesis is not fully understood yet. Yes-associated protein (YAP) acts as a transcriptional regulator of genes involved in cell proliferation and apoptosis, activating pathways associated with cystic growth and neoplastic progression. Objective: To analyze the immunohistochemical expression of YAP protein and correlate it with markers involved in cell proliferation and apoptosis in benign epithelial odontogenic lesions. Methods: The sample consisted of 95 cases of odontogenic lesions - 25 dentigerous cysts (DCs), 30 non-syndromic odontogenic keratocyst (OKCs), 30 conventional AMB (C-AMBs), and 10 unicystic AMB (UAMBs) -, in addition to 10 specimens of dental follicles (DF). Clinicodemographic data collection was carried out, as well as morphological analysis for better characterization of the sample. The histological sections were submitted to the immunohistochemical technique using YAP, cyclin D1, Ki-67, and Bcl-2 antibodies, and their immunoexpression analysis was performed qualitatively and quantitatively, through an adapted methodology. The collected data were submitted for descriptive and statistical analysis (p ≤ 0.05). Results: There was a slight predilection for women (n = 55; 57.6%) and individuals aged between 21 and 40 years (n = 50; 47.6%), with the posterior region of the mandible as the most affected site (64%). Analysis of YAP immunoexpression revealed higher expression levels in OKCs, especially in the basal and parabasal layers, followed by U-AMBs and C-AMBs, which showed moderate immunoreactivity, predominantly in peripheral cells. In addition, there were significant differences in YAP immunoexpression between the analyzed groups, with positive and statistically significant correlations between YAP and cyclin D1 in DCs and U-AMBs, and between YAP and Ki-67 in U-AMBs (p < 0.05). However, between YAP and Bcl-2 immunoexpression, there was no statistically significant correlation. Conclusions: YAP may influence on the cell proliferation of odontogenic cysts and tumors epithelium, thus helping with the progression of the different odontogenic lesions (AU) .

NDFIP1 limits cellular TAZ accumulation via exosomal sorting to inhibit NSCLC proliferation

NDFIP1 has been previously reported as a tumor suppressor in multiple solid tumors, but the function of NDFIP1 in NSCLC and the underlying mechanism are still unknown. Besides, the WW domain containing proteins can be recognized by NDFIP1, resulted in the loading of the target proteins into exosomes. However, whether WW domain-containing transcription regulator 1 (WWTR1, also known as TAZ) can be packaged into exosomes by NDFIP1 and if so, whether the release of this oncogenic protein via exosomes has an effect on tumor development has not been investigated to any extent. Here, we first found that NDFIP1 was low expressed in NSCLC samples and cell lines, which is associated with shorter OS. Then, we confirmed the interaction between TAZ and NDFIP1, and the existence of TAZ in exosomes, which requires NDFIP1. Critically, knockout of NDFIP1 led to TAZ accumulation with no change in its mRNA level and degradation rate. And the cellular TAZ level could be altered by exosome secretion. Furthermore, NDFIP1 inhibited proliferation in vitro and in vivo, and silencing TAZ eliminated the increase of proliferation caused by NDFIP1 knockout. Moreover, TAZ was negatively correlated with NDFIP1 in subcutaneous xenograft model and clinical samples, and the serum exosomal TAZ level was lower in NSCLC patients. In summary, our data uncover a new tumor suppressor, NDFIP1 in NSCLC, and a new exosome-related regulatory mechanism of TAZ.