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Analysis of purinergic enzymes expression in different models of glioblastoma Silveira PS,3, Moraes GS 3, Iser IC 1 ,2, Beckenkamp L Z 1,2, Wink MR 1,2 1 Laboratory of Cell Biology, Federal University of Health Sciences of Porto Alegre (UF


Glioblastoma (GBM) is the most common primary brain tumor of adults and is associated with a poor prognosis. Despite efforts to treat it with surgical resection, chemo and radiotherapy, it is still considered an incurable disease. Purinergic system is an signaling pathway composed of enzymes, nucleosides and nucleotides and receptors, thereby regulating different cellular functions However, few studies have compared the expression of enzymes in human samples.


Our goal is to evaluate expression of Ecto-nucleotide pyrophosphatase/phosphodiesterase 2 (ENPP2),Ecto-5′-nucleotidase (CD73) and Ectonucleosídeo Trifosfato Difosfoidrolase (E-NTPDase) 1 and 2 antibodies in a model of tumor spheroids and samples of human GBM.


The U251, U87 and A172 human cancer cell lines were cultured in a monolayer (2D system) cell culture and, incubated at 37 °C with 5% CO2 in a humidified incubator. The tumor spheroids (3D culture) were generated using the “hanging drop” method containing a pre-established number of cells in each drop, and kept in an incubator for the appropriate time. Formalin-fixed paraffin-embedded human tumor samples were obtained from patients with GBM at Grupo Hospitalar Conceição (GHC) and confirmed by histopathological analysis. For immunohistochemistry experiments, slides of tumor samples were blocked with 1% albumin solution and incubated overnight with the antibodies for the purinergic enzymes. This study was approved by CEP from UFCSPA and GHC (n 2.152.004)


Our results demonstrated cytoplasmic and membrane positivity using CD73, NTPDASE 1, ENPP 2 antibodies in samples from GBM patients and model of tumor spheroids. Analyses for NTPDase 2 and ENPPs 1 and 3 are under analysis, as well as quantification of the expression of all markers. The quantification analyses are being carried out in order to distinguish the expression of each enzyme in the study, so that it can be compared with other lower-grade gliomas.


Our results demonstrate that human GBM express different enzymes of the purinergic system, which may correlate with the malignancy of the disease, in order to promote the development of new, less invasive therapeutic resources or increasing the effectiveness of available treatments.


Keywords: purinergic system, glioblastoma and ENPP.

Financiador do resumo

Financial support: CAPES/CNPq/FAPERGS


Estudo Clínico - Tumores do Sistema Nervoso Central