RESUMO
Glioblastoma (GBM) is the most common and aggressive brain tumor in adults. The purpose of the present study was to identify GBM cell-selective secreted proteins by analyzing conditioned media (CM) from GBM, breast, and colon cancer cell lines using sequential window acquisition of all theoretical spectra-mass spectrometry (SWATH-MS) and targeted proteomics. We identified 2371 proteins in the CM from GBM and the other cancer cell lines. Among the proteins identified, 15 showed significantly higher expression in the CM from GBM cell lines than in those from other cancer cell lines. These GBM-selective secreted proteins were further quantified in the cerebrospinal fluid (CSF) from patients with GBM. Laminin subunit alpha-4 (LAMA4) and osteopontin (OPN) had increased expression levels in the CSF from GBM patients compared to those from non-brain tumor patients. In addition, the areas under the curves in a receiver operating characteristic analysis of LAMA4 and OPN were greater than 0.9, allowing for discrimination of GBM patients from non-brain tumor patients. The CSF levels of LAMA4 and OPN were also significantly correlated with the GBM tumor volume. These results suggest that LAMA4 and OPN are secreted from GBM cells into the CSF and appear to be candidates as diagnostic markers and therapeutic targets for GBM.
Assuntos
Neoplasias Encefálicas , Glioblastoma , Laminina/genética , Osteopontina/genética , Adulto , Neoplasias Encefálicas/genética , Linhagem Celular Tumoral , Glioblastoma/genética , Humanos , ProteômicaRESUMO
The extracellular matrix (ECM) initiates mechanical cues that activate intracellular signaling through matrix-cell interactions. In blood vessels, additional mechanical cues derived from the pulsatile blood flow and pressure play a pivotal role in homeostasis and disease development. Currently, the nature of the cues from the ECM and their interaction with the mechanical microenvironment in large blood vessels to maintain the integrity of the vessel wall are not fully understood. Here, we identified the matricellular protein thrombospondin-1 (Thbs1) as an extracellular mediator of matrix mechanotransduction that acts via integrin αvß1 to establish focal adhesions and promotes nuclear shuttling of Yes-associated protein (YAP) in response to high strain of cyclic stretch. Thbs1-mediated YAP activation depends on the small GTPase Rap2 and Hippo pathway and is not influenced by alteration of actin fibers. Deletion of Thbs1 in mice inhibited Thbs1/integrin ß1/YAP signaling, leading to maladaptive remodeling of the aorta in response to pressure overload and inhibition of neointima formation upon carotid artery ligation, exerting context-dependent effects on the vessel wall. We thus propose a mechanism of matrix mechanotransduction centered on Thbs1, connecting mechanical stimuli to YAP signaling during vascular remodeling in vivo.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Integrina beta1/genética , Trombospondina 1/genética , Fatores de Transcrição/genética , Remodelação Vascular/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Aorta/crescimento & desenvolvimento , Aorta/metabolismo , Artérias Carótidas/crescimento & desenvolvimento , Artérias Carótidas/metabolismo , Microambiente Celular/genética , Matriz Extracelular/genética , Matriz Extracelular/metabolismo , Adesões Focais/genética , Via de Sinalização Hippo , Humanos , Integrina beta1/metabolismo , Mecanotransdução Celular , Camundongos , Neointima/genética , Neointima/metabolismo , Proteínas Serina-Treonina Quinases/genética , Transdução de Sinais/genética , Trombospondina 1/metabolismo , Fatores de Transcrição/metabolismo , Proteínas de Sinalização YAP , Proteínas rap de Ligação ao GTP/genéticaRESUMO
Blood tests, which are used to evaluate health status, are relatively non-invasive and provide a great deal of health-related information. Blood is usually collected using a standard venous blood sampling protocol, but it is possible to collect blood from a subject's fingertip, and previous studies have investigated whether fingertip-derived blood can be used for various blood tests. In this study, the proteomes and metabolomes of venous and fingertip plasma were analyzed using non-targeted proteomics and metabolomics, respectively. In proteomics, the levels of 523 proteins were compared between venous and fingertip plasma. The correlation coefficient (r) for the relationship between protein levels of venous and fingertip plasma was 0.9999. Some proteins had high fingertip to venous plasma level ratios (finger:venous ratios), whereas others had low finger:venous ratios, and the mean±standard deviation (SD) finger:venous ratio was 0.994⯱â¯0.304. In metabolomics, 40, 33, and 216 cationic metabolites, anionic metabolites, and lipids, respectively, were detected in venous plasma, and the equivalent figures for fingertip plasma were 40, 35, and 216, respectively. Regarding the correlations between metabolite levels in venous and fingertip plasma, the correlation coefficients (r) for cationic metabolites, anionic metabolites, and lipids were 0.9952, 0.9699, and 0.9980, respectively. The mean±SD finger:venous ratio was 1.19⯱â¯0.584 for cationic metabolites, 1.23⯱â¯0.548 for anionic metabolites, and 1.00⯱â¯0.245 for lipids. Our study suggests that it might be possible to use fingertip plasma to measure plasma protein and metabolite levels, and will contribute to development of a fingertip blood sampling procedure for measuring blood biomarker levels.
