Brain Tumor Heterogeneity

Abstract

Tumor heterogeneity is the concept that different tumor cells provide distinct biomorphological lesions, gene expressions, proliferation, microenvironment and graduated capacity of metastatic lesions. Brain tumor heterogeneity has been recently discussed about the interesting interaction of chronic inflammation, microenvironment, epigenetics and glioma steam cells. Brain tumors remain a challenge with regards to medication and disease, due to the lack of treatment options and unsatisfactory results. These results might be the result of the brain tumor heterogeneity and its multiple resistance mechanisms to chemo and radiotherapy.

Resumo

Heterogeneidade tumoral significa que diferentes células tumorais levam a lesões morfológicas e fenotípicas distintas, com diferentes morfologias celulares, expressão gênica, metabolismo, microambiente, proliferação e possibilidade de lesões metastáticas. A heterogeneidade dos tumores cerebrais malignos tem sido o foco essencial de pesquisas recentes devido às interações notáveis entre genética, epigenética, microambiente e células-tronco glioma, todas mediadas por inflamação crônica. Tumores cerebrais ainda são um desafio no que tange a medicação e doença, podendo, com a carência de opções terapêuticas aliada a resultados insatisfatórios, ocorrer devido à heterogeneidade do tumor e seus múltiplos mecanismos de resistência à quimio e radioterapia. Foi realizada uma revisão da literatura na base de dados PubMed usando os termos: brain tumor, heterogeneity, epigenetic, microenvironment, e glioma stem cells.

Keywords

brain tumor - tumor heterogeneity - glioma stem cell - genetics - epigenetics - microenvironment

Palavras-chave

tumor cerebral - heterogeneidade tumoral - células-tronco glioma - genética - epigenética - microambiente

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