RESUMO
. In passages above ten and growing very actively, we observed that some human lung fibroblasts cultured under standard conditions were transformed into a lineage of epithelial-like cells (ELC). To systematically evaluate the possible mesenchymal-epithelial transition (MET) occurrence, fibroblasts were obtained from normal lungs and also from lungs affected by idiopathic interstitial diseases. When an unusual epithelial-like phenotypic change was observed, cultured cells were characterized by confocal immunofluorescence microscopy, immunoblotting, immunocytochemistry, cytofluorometry, gelatin zymography, RT-qPCR, and hybridization in a whole-transcript human microarray. Additionally, microvesicles fraction (MVs) from ELC and fibroblasts were used to induce MET, while the microRNAs (miRNAs) contained in the MVs were identified. Pattern-gene expression of the original fibroblasts and the derived ELC revealed profound changes, upregulating characteristic epithelial-cell genes and downregulating mesenchymal genes, with a marked increase of E-cadherin, cytokeratin, and ZO-1, and the loss of expression of α-SMA, collagen type I, and Thy-1 cell surface antigen (CD90). Fibroblasts, exposed to culture media or MVs from the ELC, acquired ELC phenotype. The miRNAs in MVs shown six expressed exclusively in fibroblasts, and three only in ELC; moreover, twelve miRNAs were differentially expressed between fibroblasts and ELC, all of them but one was overexpressed in fibroblasts. These findings suggest that the MET-like process can occur in human lung fibroblasts, either from normal or diseased lungs. However, the biological implication is unclear.
Assuntos
Transição Epitelial-Mesenquimal , Fibroblastos/patologia , Doenças Pulmonares Intersticiais/patologia , Pulmão/patologia , Actinas/metabolismo , Idoso , Biomarcadores/metabolismo , Micropartículas Derivadas de Células/metabolismo , Células Cultivadas , Análise por Conglomerados , Colágeno Tipo I/metabolismo , Regulação para Baixo , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Transição Epitelial-Mesenquimal/genética , Fibroblastos/metabolismo , Humanos , Doenças Pulmonares Intersticiais/metabolismo , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Fenótipo , Antígenos Thy-1/metabolismoRESUMO
Cancer is one of the leading causes of death worldwide, and breast cancer is the most common among women. Dehydroepiandrosterone (DHEA), the most abundant steroid hormone in human serum, inhibits proliferation and migration of breast cancer cells, modulating the expression of proteins involved in mesenchymal-epithelial transition (MET). However, the underlying molecular mechanisms are not fully understood. DHEA effects on the triple-negative breast cancer cell line MDA-MB-231 (mesenchymal stem-like) could be exerted by binding to receptors tyrosine kinase (RTKs) and signaling through MEK/ERK and/or PI3K/Akt pathways. In this study, MDA-MB-231 cells were exposed to DHEA in the presence of pharmacological inhibitors of these pathways and a siRNA against PIK3CA gene, which blocks PI3K pathway. Cell proliferation was measured by crystal violet staining, migration by the wound healing and transwell assays, and MET protein expression by western blot. A xenograft tumor growth in nude mice (nu-/nu-) using a siRNA against PI3K was also performed. Results showed that neither of the inhibitors used reverted the antiproliferative activity of DHEA. However, wortmannin and LY294002, inhibitors of the PI3K/Akt pathway, abolished the up- and down-regulation of E- and N-cadherin expression respectively, and inhibition of migration induced by DHEA in MDA-MB-231 cells. The siRNA that blocks the PI3K pathway, abolished the effects of DHEA on proliferation, migration, MET proteins expression and the growth of tumors in nude mice. In conclusion, these results suggest that PI3K/Akt pathway participates in the effects of DHEA on breast cancer cells.
Assuntos
Proliferação de Células/efeitos dos fármacos , Desidroepiandrosterona/farmacologia , Transição Epitelial-Mesenquimal/genética , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Animais , Caderinas/genética , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Feminino , Humanos , Camundongos , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas c-akt/genética , Transdução de Sinais/efeitos dos fármacos , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Background: Recently, markers related to molecular classification were suggested as promising therapeutic targets for treatment and prediction of prognosis in gastric cancer (GC), including c-MET, RhoA, and Claudin-18 (CLDN18). This study aimed to investigate their expression in GC and its correlation with clinicopathological characteristics and survival. Methods: We retrospectively evaluated GC patients who underwent curative gastrectomy. c-MET, RhoA, and CLDN18 were analyzed through immunohistochemistry (IHC), and groups for analysis were determined according to the median values obtained for each marker. Results: Among the 349 GC evaluated, 180 (51.6%), 59 (16.9%), and 61 (17.5%) patients were completely negative for c-MET, RhoA, and CLDN18, respectively. Total gastrectomy, D1 lymphadenectomy, poorly differentiated histology, and greater inflammatory infiltrate were more frequent in the c-MET-negative group. Diffuse type, greater inflammatory infiltrate, and advanced pT and pTNM stage were associated with low-RhoA GC. The venous invasion was more frequent in the low-CLDN18 group. Furthermore, c-MET was positively correlated with RhoA and negatively with CLDN18. HER2 expression was associated with c-MET-positive and high-CLDN18 GC; and loss of E-cadherin expression in c-MET-negative and low-RhoA GC. c-MET-negative and Low-RhoA were significantly associated with worse disease-free survival. Conclusions: c-MET, RhoA, and CLD18 expression occurred frequently in GC. RhoA GC had distinct clinicopathological characteristics related to prognosis. c-MET and RhoA were associated with survival but were not independent predictors of prognosis.
Assuntos
Proteínas Proto-Oncogênicas c-met/metabolismo , Neoplasias Gástricas , Biomarcadores Tumorais/metabolismo , Moléculas de Adesão Celular/metabolismo , Claudinas/metabolismo , Humanos , Prognóstico , Estudos Retrospectivos , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/cirurgia , Proteína rhoA de Ligação ao GTP/metabolismoRESUMO
Introducción: La metástasis del cáncer es la transferencia de células tumorales de un órgano a otro mediante una serie de multipasos secuenciales interrelacionados. Este proceso es uno de los principales retos en el tratamiento del cáncer debido a su heterogeneidad biológica. El proceso de metástasis es considerado la principal causa de muerte en esta enfermedad, reportándose que más de 90 por ciento de las muertes por cáncer son debidos a esta etapa. Objetivo: Actualizar los conocimientos sobre metástasis en tumores sólidos y su asociación con transición epitelial-mesenquimal (EMT) en relación a la evolución y emergencia del cáncer. Método: Se realizó una revisión, no sistemática, de los estudios más significativos sobre el tema, publicados en la Web of Science, Pubmed, Ebsco, Scopus e Infomed. Conclusiones: La metástasis es la principal causa de muerte del cáncer, por lo que entender las bases del mecanismo de la formación de tumores metastásicos permitirá realizar terapias más eficaces para tratar el cáncer(AU)
Introduction: Cancer metastasis is the transfer of tumor cells from one organ to another through a series of interrelated sequential multi-steps. This process is one of the main challenges in cancer treatment due to the biological heterogeneity. The metastasis process is considered the main cause of death in this disease, accounting for more than 90 percent of cancer deaths. Objective: To identify the most recent advances on solid tumor metastasis and the association with epithelial-mesenchymal transition (EMT) in relation to the evolution and emergence of cancer. Method: A non-systematic review was carried out of the most significant studies on the subject, published in Web of Science, Pubmed, Ebsco, Scopus and Infomed. Conclusions: Metastasis is the main cause of cancer death, so understanding the bases of the mechanism for metastatic tumor formation will allow for more effective therapies(AU)
Assuntos
Humanos , Masculino , Feminino , Transição Epitelial-Mesenquimal/fisiologia , Metástase Neoplásica/patologia , Metástase Neoplásica/prevenção & controle , Conhecimentos, Atitudes e Prática em Saúde , Estudos ProspectivosRESUMO
BACKGROUND/AIMS: Renal injury related to hypertension is characterized by glomerular and tubulointerstitial damage. The overactivation of the renin-angiotensin system mainly by angiotensin II (AII) seems to be a main contributor to progressive renal fibrosis. Epithelial to mesenchymal transition (EMT) is a mechanism that promotes renal fibrosis. Owing to heat shock protein 70 (Hsp70) cytoprotective properties, the chaperone exhibits an important potential as a therapeutic target. We investigate the role of Hsp70 on Angiotensin II induced epithelial mesenchymal transition within the Losartan effect in proximal tubule cells (PTCs) from a genetic model of hypertension in rats (SHR). METHODS: Primary cell culture of PTCs from SHR and Wistar Kyoto (WKY) rats were stimulated with AII, treated with Losartan (L), (L+AII) or untreated (Cc). The functional Hsp70 role in Losartan effect, after silencing its expression by cell transfection, was determined by Immunofluorescence; Western blotting; Gelatin Zymography assays; Scratch wound assays; flow cytometry; and Live Cell Time-lapse microscopy. RESULTS: (L) and (L+AII) treatments induced highly organized actin filaments and increased cortical actin in SHR PTCs. However, SHR PTCs (Cc) and (AII) treated cells showed disorganized actin. After Hsp72 knockdown in SHR PTCs, (L) was unable to stabilize the actin cytoskeleton. We demonstrated that (L) and (L+AII) increased E-cadherin levels and decreased vinculin, α-SMA, vimentin, pERK, p38 and Smad2-3 activation compared to (AII) and (Cc) SHR PTCs. Moreover, (L) inhibited MMP-2 and MMP-9 secretion, reduced migration and cellular displacement, stabilizing intercellular junctions. Notably, (L) treatment in shHsp72 knockdown SHR PTCs showed results similar to SHR PTCs (Cc). CONCLUSION: Our results demonstrate that Losartan through Hsp70 inhibits the EMT induced by AII in proximal tubule cells derived from SHR.