BDNF/TrkB/Akt signaling pathway epithelial odontogenic tumors and keratocyst : an immunohistochemical study comparative with dental germs

Odontogenic lesions (OL) are an important group of oral and maxillofacial diseases represented by odontogenic cysts, benign, and malignant tumors. The brain-derived neurotrophic factor (BDNF)/ tropomyosin receptor kinase B (TrkB) signaling pathway has multiple biological actions and has been identified as an important pathway in the proliferation, invasion, and survival of different epithelial tumors. Its role in the development of OL, however, has so far been unexplored. Our aim was to evaluate the BDNF/TrkB/Akt/p-RPS6 signaling pathway in OL of epithelial origin. This cross-sectional study comprised 3 cases of tooth germs, 25 cases of odontogenic keratocyst (OK), 29 cases of ameloblastoma (Am), and 6 cases of ameloblastic carcinoma. Immunohistochemical staining for BDNF, TrkB, p-Akt, and p-RPS6 was performed. OLs were evaluated according to the pattern of immunohistochemical expression in epithelial cells and by semiquantitative scores that considered the intensity of staining and percentage of positive cells. BDNF stromal expression was also assessed. No significant differences were observed with respect to the percentage of positive cases for all markers. Regarding the immunoreactive scores, BDNF and p-RPS6 expressions were similar in the odontogenic epithelium of all OL. However, TrkB and p-Akt were overexpressed in OK compared with ameloblastic carcinoma. In Am, epithelial BDNF was significantly higher compared with stromal expression. In conclusion, BDNF seems to participate in the development of cystic, benign, and malignant odontogenic epithelium to similar degrees. The acquisition of the invasive or malignant phenotype in odontogenic neoplasms is not associated with alterations in the BDNF/TrkB/Akt/RPS6 axis, which could be implicated in the differentiation process.The São Paulo State Research Foundationhttp://www.appliedimmunohist.comhj2022Oral Pathology and Oral Biolog

Immunohistochemical relation between VEGFR1, VEGFR2, CD31 e KI-67 with behaviour and prognosis of actinic cheilitis and lower lip squamous cell carcinoma

A angiogênese patológica se caracteriza por um processo multifásico controlado por diferentes fatores e está relacionada com o desenvolvimento de tumores malignos. O objetivo do presente estudo foi determinar as contribuições dos receptores do fator de crescimento vascular endotelial (VEGFR1 e VEGFR2) durante a carcinogênese labial, investigar a correlação destes biomarcadores com a microdensidade vascular (MDV) e o perfil proliferativo dos casos, e a associação com fatores de risco, parâmetros clínico-patológicos e sobrevida. Prontuários médicos de 27 casos de queilite actínica (QA) e 46 casos de carcinoma espinocelular de lábio (CECL) foram analisados. As lesões foram classificadas de acordo com o padrão histopatológico e submetidas a marcação imunoistoquímica para VEGFR1, VEGFR2, CD31 e Ki-67. Foi analisada toda a extensão epitelial nos casos de QA e o fronte de invasão nos casos de CECL. As lâminas imunomarcadas por VEGFR1 e VEGFR2 foram submetidas à análise semi-quantitativa baseada no percentual de células epiteliais e inflamatórias positivas, enquanto que a marcação de CD31 e Ki-67 foi analisada de maneira quantitativa a fim de determinar a MDV e o índice proliferativo, respectivamente. Uma maior expressão de VEGFR1 foi observada nas células epiteliais de QA quando comparadas com o CECL (p<0.001). Um aumento linear de VEGFR1 foi observado nas células inflamatórias a partir dos casos de QA até o CECL (p<0.001). Uma maior expressão de VEGFR2 foi observada nas células epiteliais e inflamatórias na QA quando comparado com o CECL (p=0.02). Não foram encontradas associações entre VEGFR1 e VEGFR2 com a MDV, índice proliferativo e parâmetros clinico-patológicos. Nos casos de QA foi possível identificar uma correlação positiva significativa entre a MDV e o índice proliferativo (p=0.02). Os achados do presente estudo indicam que o VEGFR1 e VEGFR2 estão expressos durante a carcinogênese labial. A ativação do VEGFR1 e VEGFR2 nas células epiteliais e inflamatórias parece ser um evento precoce na carcinogênese labial e podem regular esta via de forma autócrina e parácrina.Pathological angiogenesis represents a multistep process controlled by different factors and is related to the development of malignant tumors. The aim of the present study was to determine the contributions of vascular endothelial growth factor receptors (VEGFR1 and VEGFR2) in lip carcinogenesis, to investigate the correlation of these biomarkers with microvessel density (MVD) and proliferative profile of cases as well as the association with risk factors, clinico-pathologic parameters and overall survival. Medical records of 27 cases of actinic cheilitis (AC) and 46 cases of low lip squamous cell carcinoma (LLSCC) were analyzed. Lesions were classified according histological pattern and submitted to immunostaining for VEGFR1, VEGFR2, CD31 and Ki-67. For AC, the entire epithelial length was analyzed and for LLSCC the invasive front of tumor. VEGFR1 and VEGFR2 immunostained sections were submitted to a semi-quantitative analysis based on the percentage of positive epithelial and inflammatory cells, while CD31 and Ki-67 were submitted to quantitative analysis to determine the MVD and proliferative labeling index, respectively. A higher expression of VEGFR1 was observed in epithelial cells of AC when compared to LLSCC (p<0.001 A linear increase of VEGFR1 in inflammatory cells was noted from AC to LLSCC (p<0.001). Higher expression of VEGFR2 was observed in epithelial and inflammatory infiltrate of AC compared to LLSCC (p=0.02). There was no association between VEGFR1 and VEGFR2 with MVD, proliferative labeling index and clinico-pathological parameters. In AC, a significant positive correlation was observed between MVD and proliferative labeling index (p=0.02). Our findings indicate that both receptors are expressed during lip carcinogenesis. The activation of VEGFR1 and VEGFR2 in epithelial and inflammatory cells appears to be an early event during lip carcinogenesis and may be involved in autocrine and paracrine regulatory pathways

PI3K/AKT/mTOR pathway activation in actinic cheilitis and lip squamous cell carcinomas

Alterações epiteliais observadas na queilite actínica (QA) e no carcinoma espinocelular (CEC) de lábio inferior foram estudadas com diferentes marcadores, a fim de observar fatores diagnósticos e prognósticos para ambas as lesões. O objetivo do estudo foi analisar a ativação do PI3K, pAktSer473 e pRPS6, importante cascata da via PI3K/Akt/mTOR, na mucosa oral normal (MON), QA e CEC de lábio comparando com aspectos clínico-demográficos e histopatológicos. Nove casos de MON, 38 de QA e 40 de CEC de lábio foram incluídos. Reações imunohistoquímicas para PI3K, pAktSer473 e pRPS6 foram realizados em todos os casos. Para cada caso, a extensão total da lesão foi analisada e um escore imunorreativo (IRS) foi designado. O IRS foi calculado multiplicando a porcentagem de células positivas (PP) (coradas 0-2) pela intensidade da coloração (SI) (coradas 0-3). O PI3K demonstrou um aumento gradual e significativo de MON, QA para CEC de lábio. O marcador pAktSer473 foi significativamente maior na QA e CEC de lábio quando comparado a MON, no entanto, não foi observada diferença entre QA e CEC de lábio. A ativação do pRPS6 diminuiu significativamente no CEC de lábio quando comparado a MON. De acordo com nossos resultados, a modificação no PI3K/Akt/mTOR esteve significativamente associada ao CEC de lábio. A identificação dessa modificação da via de sinalização no câncer labial é importante não apenas para entender o processo de carcinogênese, mas também para identificar pacientes que podem se beneficiar da terapia-alvo, especialmente aqueles com QA.Epithelial changes observed in actinic cheilitis (AC) and lower lip squamous cell carcinoma (LLSCC) have been studied using different markers in order to observe diagnostic and prognostic factors for both lesions. The aim of the study is to analyses the activation of PI3K, pAktSer473 and pRPS6, important downstream of Pi3K/Akt/mTOR pathway, in normal oral mucosa (NOM), actinic cheilitis (AC) and lower lip squamous cell carcinoma (LLSCC) comparing with clinico-demographic and histopathological aspects. Nine cases of NOM, 38 of AC and 40 of LLSCC were included. Immunohistochemical for PI3K, pAktSer473 and pRPS6 were performed in all cases. For each case, the full extent of the lesion was analyzed and an immunoreactive score (IRS) was designated. The IRS was calculated by multiplying percentage of positive cells (PP) (stained 0-2) by staining intensity (SI) (stained 0-3). PI3K demonstrated a significant gradual increase from NOM, AC to LLSCC. pAktSer473 marker was significantly higher in AC and LLSCC when compared to NOM, however, no difference was observed between AC and LLSCC. Activation of pRPS6 was significantly decreased in LLSCC when compared to NOM. According to our results modification in PI3K/Akt/mTOR were significantly associated with LLSCC. Identification of modification on this signaling pathway in lip cancer is important not only for understand the carcinogenesis process but also for identifying patients who may benefit from target therapy especially with AC

Immunohistochemical relation between VEGFR1, VEGFR2, CD31 e KI-67 with behaviour and prognosis of actinic cheilitis and lower lip squamous cell carcinoma

A angiogênese patológica se caracteriza por um processo multifásico controlado por diferentes fatores e está relacionada com o desenvolvimento de tumores malignos. O objetivo do presente estudo foi determinar as contribuições dos receptores do fator de crescimento vascular endotelial (VEGFR1 e VEGFR2) durante a carcinogênese labial, investigar a correlação destes biomarcadores com a microdensidade vascular (MDV) e o perfil proliferativo dos casos, e a associação com fatores de risco, parâmetros clínico-patológicos e sobrevida. Prontuários médicos de 27 casos de queilite actínica (QA) e 46 casos de carcinoma espinocelular de lábio (CECL) foram analisados. As lesões foram classificadas de acordo com o padrão histopatológico e submetidas a marcação imunoistoquímica para VEGFR1, VEGFR2, CD31 e Ki-67. Foi analisada toda a extensão epitelial nos casos de QA e o fronte de invasão nos casos de CECL. As lâminas imunomarcadas por VEGFR1 e VEGFR2 foram submetidas à análise semi-quantitativa baseada no percentual de células epiteliais e inflamatórias positivas, enquanto que a marcação de CD31 e Ki-67 foi analisada de maneira quantitativa a fim de determinar a MDV e o índice proliferativo, respectivamente. Uma maior expressão de VEGFR1 foi observada nas células epiteliais de QA quando comparadas com o CECL (p<0.001). Um aumento linear de VEGFR1 foi observado nas células inflamatórias a partir dos casos de QA até o CECL (p<0.001). Uma maior expressão de VEGFR2 foi observada nas células epiteliais e inflamatórias na QA quando comparado com o CECL (p=0.02). Não foram encontradas associações entre VEGFR1 e VEGFR2 com a MDV, índice proliferativo e parâmetros clinico-patológicos. Nos casos de QA foi possível identificar uma correlação positiva significativa entre a MDV e o índice proliferativo (p=0.02). Os achados do presente estudo indicam que o VEGFR1 e VEGFR2 estão expressos durante a carcinogênese labial. A ativação do VEGFR1 e VEGFR2 nas células epiteliais e inflamatórias parece ser um evento precoce na carcinogênese labial e podem regular esta via de forma autócrina e parácrina.Pathological angiogenesis represents a multistep process controlled by different factors and is related to the development of malignant tumors. The aim of the present study was to determine the contributions of vascular endothelial growth factor receptors (VEGFR1 and VEGFR2) in lip carcinogenesis, to investigate the correlation of these biomarkers with microvessel density (MVD) and proliferative profile of cases as well as the association with risk factors, clinico-pathologic parameters and overall survival. Medical records of 27 cases of actinic cheilitis (AC) and 46 cases of low lip squamous cell carcinoma (LLSCC) were analyzed. Lesions were classified according histological pattern and submitted to immunostaining for VEGFR1, VEGFR2, CD31 and Ki-67. For AC, the entire epithelial length was analyzed and for LLSCC the invasive front of tumor. VEGFR1 and VEGFR2 immunostained sections were submitted to a semi-quantitative analysis based on the percentage of positive epithelial and inflammatory cells, while CD31 and Ki-67 were submitted to quantitative analysis to determine the MVD and proliferative labeling index, respectively. A higher expression of VEGFR1 was observed in epithelial cells of AC when compared to LLSCC (p<0.001 A linear increase of VEGFR1 in inflammatory cells was noted from AC to LLSCC (p<0.001). Higher expression of VEGFR2 was observed in epithelial and inflammatory infiltrate of AC compared to LLSCC (p=0.02). There was no association between VEGFR1 and VEGFR2 with MVD, proliferative labeling index and clinico-pathological parameters. In AC, a significant positive correlation was observed between MVD and proliferative labeling index (p=0.02). Our findings indicate that both receptors are expressed during lip carcinogenesis. The activation of VEGFR1 and VEGFR2 in epithelial and inflammatory cells appears to be an early event during lip carcinogenesis and may be involved in autocrine and paracrine regulatory pathways

An Abl-FBP17 mechanosensing system couples local plasma membrane curvature and stress fiber remodeling during mechanoadaptation

Cells remodel their structure in response to mechanical strain. However, how mechanical forces are translated into biochemical signals that coordinate the structural changes observed at the plasma membrane (PM) and the underlying cytoskeleton during mechanoadaptation is unclear. Here, we show that PM mechanoadaptation is controlled by a tension-sensing pathway composed of c-Abl tyrosine kinase and membrane curvature regulator FBP17. FBP17 is recruited to caveolae to induce the formation of caveolar rosettes. FBP17 deficient cells have reduced rosette density, lack PM tension buffering capacity under osmotic shock, and cannot adapt to mechanical strain. Mechanistically, tension is transduced to the FBP17 F-BAR domain by direct phosphorylation mediated by c-Abl, a mechanosensitive molecule. This modification inhibits FBP17 membrane bending activity and releases FBP17-controlled inhibition of mDia1-dependent stress fibers, favoring membrane adaptation to increased tension. This mechanoprotective mechanism adapts the cell to changes in mechanical tension by coupling PM and actin cytoskeleton remodeling