RESUMO
Podocyte dysfunction plays a crucial role in renal injury and is identified as a key contributor to proteinuria in Fabry disease (FD), primarily impacting glomerular filtration function (GFF). The α3ß1 integrins are important for podocyte adhesion to the glomerular basement membrane, and disturbances in these integrins can lead to podocyte injury. Therefore, this study aimed to assess the effects of chloroquine (CQ) on podocytes, as this drug can be used to obtain an in vitro condition analogous to the FD. Murine podocytes were employed in our experiments. The results revealed a dose-dependent reduction in cell viability. CQ at a sub-lethal concentration (1.0 µg/mL) induced lysosomal accumulation significantly (p < 0.0001). Morphological changes were evident through scanning electron microscopy and immunofluorescence, highlighting alterations in F-actin and nucleus morphology. No significant changes were observed in the gene expression of α3ß1 integrins via RT-qPCR. Protein expression of α3 integrin was evaluated with Western Blotting and immunofluorescence, demonstrating its lower detection in podocytes exposed to CQ. Our findings propose a novel in vitro model for exploring secondary Fabry nephropathy, indicating a modulation of α3ß1 integrin and morphological alterations in podocytes under the influence of CQ.
Assuntos
Doença de Fabry , Integrina alfa3beta1 , Nefropatias , Podócitos , Animais , Camundongos , Doença de Fabry/metabolismo , Integrina alfa3beta1/genética , Integrina alfa3beta1/metabolismo , Nefropatias/metabolismo , Podócitos/metabolismo , Insuficiência RenalRESUMO
To investigate E-cadherin, ß-catenin, and α2ß1 and α3ß1 integrins in 40 samples of non-metastatic and metastatic oral squamous cell carcinoma (OSCC) with positive cervical lymph nodes (LN). Immunohistochemistry was used to evaluate expression in the lesion center (LC) and invasive tumor front (ITF) of non-metastatic (n=18) and metastatic (n=22) OSCC and in the LN on the metastatic neoplastic cells (MNC; n=22). In metastatic OSCC, E-cadherin and ß-catenin presented significantly lower cytoplasmic membrane expression in the ITF and MNC when compared to the LC and lower cytoplasmic expression in MNC when compared to the LC and ITF (p<0.05). Integrins α2ß1 and α3ß1 showed high cytoplasmic expression in the LC, ITF and MNC (p>0.05). A positive correlation was observed between E-cadherin cytoplasmic expression and α2ß1 (p=0.860) and α3ß1 (p=0.975) expression. When comparing the primary sites of metastatic and non-metastatic disease, ß-catenin presented lower cytoplasmic membrane (p=0.013) expression in metastatic OSCC. E-cadherin presented low expression and the integrins high expression in both groups. Abnormal expression of ß-catenin and E-cadherin associated with high expression of α2ß1 and α3ß1 integrins contribute to LN metastasis in OSCC.
Assuntos
Caderinas/metabolismo , Carcinoma de Células Escamosas/metabolismo , Integrina alfa2beta1/metabolismo , Integrina alfa3beta1/metabolismo , Metástase Linfática/patologia , Neoplasias Bucais/metabolismo , beta Catenina/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/patologia , Feminino , Humanos , Linfonodos/metabolismo , Linfonodos/patologia , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/patologia , Adulto JovemRESUMO
OBJECTIVE AND METHODS: This study analyzed the distribution, intensity, and pattern of immunohistochemical expression of α2ß1, α3ß1, and α5ß1 integrins in squamous cell carcinoma (SCC) of the lower lip and tongue to identify biomarkers that reflect the clinical course of this cancer. Immunoexpression was compared considering prognostic parameters such as anatomic site, metastasis, and histologic grade of malignancy. RESULTS: Immunohistochemical analysis at the invasion front showed a predominance of granular cytoplasmic expression of the integrins studied. In most cases, immunopositive cells were diffusely distributed in the tumors, irrespective of their location, except for α3ß1 integrin-positive cells which were focally distributed in 53.3% of tongue SCC cases. With respect to staining intensity, positive staining for α2ß1 integrin was observed in 80% of lower lip SCCs and in 93.3% of tongue SCCs. Staining for α3ß1 integrin was moderately positive in 60% of lower lip and tongue SCCs. The staining intensity of α5ß1 integrin was moderately and strongly positive in 53.3% and 46.7% of lower lip SCCs, respectively, and in 46.7% and 53.3% of tongue SCCs. CONCLUSIONS: The strong immunoreactivity for integrins α2ß1, α3ß1, and α5ß1 seen in the oral SCC cases studied suggests a significant participation of these proteins in oral carcinogenesis. However, their expression does not reflect the clinical course of this cancer.
Assuntos
Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/patologia , Transformação Celular Neoplásica/patologia , Integrina alfa2beta1/genética , Integrina alfa3beta1/genética , Integrina alfa5beta1/genética , Neoplasias Labiais/patologia , Neoplasias da Língua/patologia , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/genética , Transformação Celular Neoplásica/genética , Feminino , Expressão Gênica , Humanos , Imuno-Histoquímica , Neoplasias Labiais/diagnóstico , Neoplasias Labiais/genética , Masculino , Gradação de Tumores , Neoplasias da Língua/diagnóstico , Neoplasias da Língua/genéticaRESUMO
The aim of the present study was to compare the expression of α2ß1, α3ß1, and α5ß1 integrins between 28 pleomorphic adenomas (PAs) and 10 adenoid cystic carcinomas (ACCs), and investigate differences in the expression of these integrins according to histologic subtypes of ACCs. It was taken into consideration the presence or absence, distribution, and localization of integrin immunoexpression. There was immunoreactivity in the intercellular contacts of the strands, nests, and solid sheets of PAs, as well as in the luminal and nonluminal cells of the duct-like structures, with a predominant immunoexpression in the luminal cells. The immunoexpression in ACCs varied with histologic subtype of the tumor. It was verified for a tendency of absence and/or reduced expression of all integrins in the solid subtype of ACCs. In general, PAs revealed a more diffuse and remarkable immunoexpression of all studied integrins than ACCs. The reduced integrins expression in ACC may be related to a lesser degree of cell differentiation in this neoplasm. Moreover, the absence and/or reduced expression of the studied integrins in solid ACC suggest a possible role in pathogenesis and more aggressive biological behavior of this histologic subtype.
Assuntos
Adenoma Pleomorfo/genética , Biomarcadores Tumorais/genética , Carcinoma Adenoide Cístico/genética , Integrina alfa2beta1/genética , Integrina alfa3beta1/genética , Integrina alfa5beta1/genética , Neoplasias das Glândulas Salivares/genética , Adenoma Pleomorfo/diagnóstico , Adenoma Pleomorfo/patologia , Carcinoma Adenoide Cístico/diagnóstico , Carcinoma Adenoide Cístico/patologia , Expressão Gênica , Humanos , Imuno-Histoquímica , Neoplasias das Glândulas Salivares/diagnóstico , Neoplasias das Glândulas Salivares/patologiaRESUMO
The expression of integrins alpha2beta1, alpha3beta1, and alpha5beta1 in 30 ameloblastomas (20 solid and 10 unicystic tumors), 12 adenomatoid odontogenic tumors (AOTs), and 5 human tooth germs in different stages of odontogenesis was analyzed. The distribution, location, pattern, and intensity of immunohistochemical expression were evaluated. Intensity was analyzed using scores (0 = absence, 1 = weak staining, and 2 = strong staining). No difference in the immunoexpression of the integrins was observed between solid and unicystic ameloblastomas. When these two ameloblastoma types were pooled into a single group, the following significant differences were found: immunoexpression of integrin alpha2beta1 was stronger in ameloblastomas than in AOTs and tooth germs, and the expression of integrin alpha5beta1 was stronger in ameloblastomas than in AOTs. The lack of detection of integrin alpha3beta1 in tooth germs and its detection in the odontogenic tumors studied suggest that this integrin might be used as a marker of neoplastic transformation in odontogenic tissues.
Assuntos
Ameloblastoma/metabolismo , Biomarcadores Tumorais/metabolismo , Neoplasias Maxilomandibulares/metabolismo , Receptores de Colágeno/metabolismo , Germe de Dente/metabolismo , Ameloblastoma/patologia , Técnica Direta de Fluorescência para Anticorpo , Humanos , Técnicas Imunoenzimáticas , Integrina alfa2beta1/metabolismo , Integrina alfa3beta1/metabolismo , Integrina alfa5beta1/metabolismo , Neoplasias Maxilomandibulares/patologia , Germe de Dente/embriologiaRESUMO
Ameloblastoma is an odontogenic neoplasm characterized by local invasiveness and a tendency toward recurrence, whereas adenomatoid odontogenic tumor (AOT) is an indolent neoplasm. The objective of the present study was to immunohistochemically analyze the role of alpha2beta1, alpha3beta1, and alpha5beta1 integrins in the cellular events and cell-matrix interactions that occur in these tumors and their consequent repercussions on the architectural arrangement and biologic behavior of these lesions. Paraffin-embedded specimens from 30 ameloblastomas (20 solid and 10 unicystic tumors) and 12 AOTs were submitted to immunohistochemistry using the catalyzed signal amplification system. A difference in the pattern of integrin expression was observed between the various histologic types of ameloblastoma. No significant difference in labeling intensity was observed between unicystic and solid ameloblastomas, but comparison between ameloblastomas and AOT showed a significantly stronger expression of alpha5beta1 integrin in the former (P < .05). Our findings suggest an important role of the integrins studied in the architectural characteristics of ameloblastomas and AOTs and a possible participation of alpha5beta1 integrin in the mechanism of local invasion of ameloblastomas.
Assuntos
Ameloblastoma/patologia , Integrina alfa2beta1/fisiologia , Integrina alfa3beta1/fisiologia , Integrina alfa5beta1/fisiologia , Neoplasias Maxilomandibulares/patologia , Tumores Odontogênicos/patologia , Ameloblastoma/metabolismo , Comunicação Celular , Regulação Neoplásica da Expressão Gênica , Humanos , Integrina alfa2beta1/genética , Integrina alfa3beta1/genética , Integrina alfa5beta1/genética , Neoplasias Maxilomandibulares/metabolismo , Invasividade Neoplásica , Recidiva Local de Neoplasia/patologia , Tumores Odontogênicos/fisiopatologiaRESUMO
The expression of laminin-1 chains (beta1 and gamma1), laminin-2 (merosin), integrin receptors to laminin (alpha3beta1 and alpha6beta4) and cytokeratin (CK20) were studied by immunohistochemical methods in gastric biopsies from antrum of 25 patients. H. pylori gastritis was found in 19 cases and intestinal metaplasia (IM) in four from these 19. Another 13 biopsies, all with IM were immunostained to laminin-2. Laminin-1 chains in normal and gastritis areas without IM were expressed as a strong, linear and continuous deposit in the basement membranes of the superficial and glandular epithelium. In metaplastic glands the reactivity to laminin-1 chains was decreased. Merosin was discontinuous when a moderate to accentuated H. pylori glandular colonization was present. Samples with IM were negative to laminin-2. The alpha3beta1 and alpha6beta4 integrins were negative only in IM gastric biopsies. The CK20 immunoreactivity was strong and homogeneous in the cells at the tip and the upper portion of foveolae in normal areas and in gastritis with IM the reactivity to CK 20 was heterogeneous. A differential expression of laminin isoforms is related to inflammation and subsequent IM caused by H. pylori. The alterations of alpha3beta1 and alpha6beta4 parallel both modifications in merosin and CK20 expression in H. pylori chronic gastritis.
Assuntos
Antígenos de Superfície/biossíntese , Gastrite/metabolismo , Infecções por Helicobacter/metabolismo , Helicobacter pylori , Integrinas/biossíntese , Proteínas de Filamentos Intermediários/biossíntese , Laminina/biossíntese , Receptores de Laminina/biossíntese , Adulto , Idoso , Anticorpos Monoclonais , Matriz Extracelular/metabolismo , Feminino , Imunofluorescência , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patologia , Humanos , Imuno-Histoquímica , Integrina alfa3beta1 , Integrina alfa6beta4 , Queratina-20 , Masculino , Pessoa de Meia-IdadeRESUMO
AIMS: Polymorphous low-grade adenocarcinoma (PLGA) and adenoid cystic carcinoma (ACC) are malignant salivary gland tumours bearing many similar histological patterns. This study was undertaken to show how the presence and distribution of collagen IV and laminin, and their ligands (integrin alpha2beta1 and alpha3beta1 components), can reveal histoarchitectural differences which distinguish these two entities. METHODS AND RESULTS: Five cases of ACC and five cases of PLGA from the archives of the Oral Pathology Department of the School of Dentistry of the São Paulo University were submitted to immunostaining with the antibodies to collagen IV, laminin, and integrins alpha2beta1 and alpha3beta1 using the streptavidin-biotin-peroxidase technique. Positive and negative controls were included. PLGA showed a thin line of collagen IV and laminin surrounding structures composed of a single cell layer. Integrins were expressed as a widespread and granular pattern. A thick line of collagen and laminin was observed around the neoplastic structures of ACC. Both integrins were expressed in intercellular spaces and around luminal spaces of tubular structures. CONCLUSIONS: Collagen IV and laminin, and their integrin ligands, are useful in demonstrating that neoplastic ductal units of PLGA are composed of a single cell layer, being distinct from ACC which contains structures composed of two layers of neoplastic cells.