Extracellular Matrix Proteome Remodeling in Human Glioblastoma and Medulloblastoma

Medulloblastomas (MBs) and glioblastomas (GBMs) are high-incidence central nervous system tumors. Different origin sites and changes in the tissue microenvironment have been associated with the onset and progression. Here, we describe differences between the extracellular matrix (ECM) signatures of these tumors. We compared the proteomic profiles of MB and GBM decellularized tumor samples between each other and their normal decellularized brain site counterparts. Our analysis revealed that 19, 28, and 11 ECM proteins were differentially expressed in MBs, GBMs, and in both MBs and GBMs, respectively. Next, we validated key findings by using a protein tissue array with 53 MB and 55 GBM cases and evaluated the clinical relevance of the identified differentially expressed proteins through their analysis on publicly available datasets, 763 MB samples from the GSE50161 and GSE85217 studies, and 115 GBM samples from RNAseq-TCGA. We report a shift toward a denser fibrillary ECM as well as a clear alteration in the glycoprotein signature, which influences the tumor pathophysiology. MS data have been submitted to the PRIDE repository, project accession: PXD023350

Severe acute traumatic brain injury: transcriptoma analysis by RNA-SEQ

O traumatismo crânioencefálico (TCE) é um problema de saúde mundial, devido às disfunções neurológicas causadas pelas lesões primárias e secundárias subsequentes, sendo a principal causa de morbidade e mortalidade em adultos jovens. A neuroinflamação deflagrada pelo TCE é uma resposta importante para conter a extensão do dano tecidual cerebral e para a recuperação da área pericontusional, no entanto, a manutenção deste processo leva a formação cicatricial disfuncional. Considerando o papel crítico das quimiocinas na neuroinflamação e com base nas descrições prévias, selecionamos dois receptores de quimiocinas (CXCR4, CXCR7) e seus ligantes cognatos (CXCL11 e CXCL12) e analisamos os níveis de expressão em 22 amostras de tecido cerebral pericontusional de pacientes com TCE grave com indicação cirúrgica, comparados com 20 amostras de controles de autópsia sem TCE. Aumentos significativos da expressão gênica de ambos receptores e seus ligantes foram observados em TCE e estes exibiram alta sensibilidade e especificidade para discriminar TCE de controle sem TCE. O nível de expressão de CXCR7 se correlacionou com as expressões dos ligantes CXCL11 e CXCL12, no entanto, tais correlações não foram observadas para CXCR4. Notadamente, o aumento dos níveis de expressão destas quimiocinas associou-se à evolução clínica favorável em até 6 meses de seguimento do TCE. Subsequentemente foi realizada a análise do transcriptoma por RNA-Seq de 10 amostras de TCE comparadas a 10 amostras controles de autópsia sem TCE para identificar as vias de sinalização correlacionadas à neuroinflamação. As bibliotecas foram preparadas com QuantSeq 3´mRNA-Seq e sequenciadas na plataforma Illumina NextSeq 500 com geração de cerca de 5 milhões de leituras por amostra. As análises de enriquecimento de vias de sinalização identificaram aumento de expressão de genes envolvidos nas vias de inflamação, angiogênese e remodelamento de matriz extracelular (MEC) e diminuição da expressão de genes relacionados ao transporte de íons e à transmissão sináptica nas amostras de TCE em comparação aos controles sem TCE. Observou-se uma rede altamente conectada entre os genes regulados positivamente, com enriquecimento preponderante de genes relacionados à inflamação, com destaque ao gene CCL2, codificando um ligante que quimiocina, com participação nos três processos identificados. O aumento da expressão de CCL2 foi confirmada ao nível gênico por PCR em tempo real e ao nível proteico por imunoistoquímica em casuística expandida de 22 TCEs e 20 controles sem TCE. O nível de expressão de CCL2 correlacionou-se fortemente aos níveis de expressão de SPHK1, associado à regulação de proliferação e sobrevivência celular. A ativação concomitante das vias de sinalização de angiogênese e de remodelamento da MEC sugerem ativação de processos para a recuperação do tecido danificado. Os genes envolvidos nos processos biológicos identificados na fase aguda do TCE humanos são potenciais candidatos para monitoramento da evolução clínica e para novas estratégias terapêuticas. Portanto, análises adicionais de suas funções no TCE serão importantes em futuras investigaçõesTraumatic brain injury (TBI) is a worldwide health problem, due to neurological dysfunctions caused by primary and subsequent secondary injuries, being the main cause of morbidity and mortality in young adults. Neuroinflammation triggered by TBI is an important response to contain the extension of brain tissue damage and for the recovery of the pericontusional area. However, the maintenance of this process leads to dysfunctional scar formation. Considering the critical role of chemokines in neuroinflammation and based on previous descriptions, we selected two chemokine receptors (CXCR4, CXCR7) and their cognate ligands (CXCL11 and CXCL12) and analyzed their expression levels in 22 pericontusional brain tissue samples from patients with severe TBI with surgical indication, compared with 20 samples from autopsy controls without TBI. Significant increase in gene expression of both receptors and their ligands were observed in TBI and they exhibited high sensitivity and specificity to discriminate TBI samples from controls. The level of CXCR7 expression correlated with the expressions of CXCL11 and CXCL12 ligands, but such correlations were not observed for CXCR4. Notably, the increase in the expression levels of these chemokines was associated with a favorable clinical evolution in up to 6 months of TBI follow-up. Subsequently, RNA-Seq transcriptome analysis of 10 TBI samples compared to 10 samples from autopsy controls without TBI. was performed to identify signaling pathways correlated with neuroinflammation. Libraries were prepared with QuantSeq 3\'mRNA-Seq and sequenced on the Illumina NextSeq 500 platform generating approximately 5 million reads per sample. Signaling pathway enrichment analyzes identified increased expression of genes involved in inflammation, angiogenesis and extracellular matrix (ECM) remodeling pathways and decreased expression of genes related to ion transport and synaptic transmission in TBI compared to the controls. A highly connected network was observed among the positively regulated genes, with a preponderant enrichment of genes related to inflammation, especially the CCL2 gene, encoding for a chemokine ligand, with participation in the three identified processes. The CCL2 increased expression was confirmed at the gene level by real-time PCR and at the protein level by immunohistochemistry, in an expanded series of 22 TBI and 20 controls. The CCL2 expression level correlated strongly with the SPHK1 expression level, a gene associated with regulation of cell proliferation and survival. The concomitant activation of angiogenesis and ECM remodeling pathways suggested activation of processes for the recovery of damaged tissue. The identified genes and the corresponding signaling pathways at the acute phase of human TBI are potential candidates for monitoring the clinical course and for new therapeutic strategies. Therefore, further analysis of their role in TBI will worthwhile in future investigation

Objective value on Apparent diffusion coefficient (ADC) map to categorize the intensity of diffusion-weighted imaging (DWI) restriction for prostate cancer detection on multiparametric prostate MRI

ABSTRACT Purpose: To identify objective and subjective criteria on multiparametric prostate MRI that can be helpful for prostate cancer detection. Materials and Methods: Retrospective study, IRB approved, including 122 patients who had suspicious lesion on MRI and who underwent prostate biopsy with ultrasonography (US)/MRI imaging fusion. There were 60 patients with positive biopsies and 62 with negative biopsies. MRI of these patients were randomized and evaluated independently by two blinded radiologists. The following variables were analyzed in each lesion: morphology, contours, T2 signal, diffusion restriction (subjective impression and objective values), hyper-enhancement, contact with transition zone or prostatic contour, prostatic contour retraction, Likert and PIRADS classification. Results: Apparent diffusion coefficient (ADC) value was the best predictor of positivity for prostate cancer, with mean value of 1.08 (SD 0.20) and 1.09 mm2/sec (SD 0.24) on negative biopsies and 0.81 (SD 0.22) and 0.84 mm2/sec (SD 0.22) on positive biopsies for readers 1 and 2, respectively (p 0.6) only in lesion size and ADC values. Conclusions: Diffusion restriction with lower ADC-values is the best parameter to predict cancer on MRI prior to biopsy. Efforts to establish an ADC cutoff value would improve cancer detection, especially for less experience reader