Pleiotrophin expression in astrocytic and oligodendroglial tumors and it's correlation with histological diagnosis, microvascular density, cellular proliferation and overall survival.
BACKGROUND
Pleiotrophin (PTN) is a secreted cytokine with several properties related with tumor development, including differentiation, angiogenesis, invasion, apoptosis and metastasis. There is evidence that PTN has also a relevant role in primary brain neoplasms and its inactivation could be important to treatment response. Astrocytic and oligodendroglial tumors are the most frequent primary brain neoplasms. Astrocytic tumors are classified as pilocytic astrocytoma (PA), diffuse astrocytoma (DA), anaplastic astrocytoma (AA) and glioblastoma (GBM). Oligodendroglial tumors are classified as oligodendroglioma (O) and anaplastic oligodendroglioma (AO). The aim of the present study was to compare PTN expression, in astrocytomas and oligodendrogliomas and its association with the histological diagnosis, microvascular density, proliferate potential and clinical outcome.


METHODS
Seventy-eight central nervous system tumors were analyzed. The histological diagnosis in accordance with WHO classification was: 13PA, 18DA, 8AA, 15GBM, 16O and 8AO. Immunohistochemistry was realized with these specific antibodies: pleiotrophin, CD31 to microvascular density and Ki-67 to cell proliferation.


RESULTS
PTN expression was significantly higher in GBM and AA when compared to PA and higher in GBM compared to DA. PTN expression did not differ between O and AO. Proliferate index and microvascular density were evaluated only in high grade tumors (AA, GBM and AO) divided in three groups according to PTN expression (low, intermediate and high). These results showed no statistical difference between PTN expression and index of cellular proliferation and neither to PTN expression and microvascular density. Overall survival (OS) analysis (months) showed similar results in high grade gliomas with different levels of PTN expression.


CONCLUSIONS
Our results suggest that PTN expression is associated with histopathological grade of astrocytomas. Proliferation rate, microvascular density and overall survival do not seem to be associated with PTN expression.
Peria
Fernanda M
FM
Department of Surgery and Anatomy, Faculty of Medicine of Ribeirão Preto of University of São Paulo (USP), Hospital das Clínicas da FMRP-USP, Campus Universitário da USP, Ribeirão Preto, São Paulo, Brazil. fernanda.peria@uol.com.br
Neder
Luciano
L
Marie
Sueli K N
SK
Rosemberg
Sergio
S
Oba-Shinjo
Sueli M
SM
Colli
Benedicto O
BO
Gabbai
Alberto A
AA
Malheiros
Suzana M F
SM
Zago
Marco A
MA
Panepucci
Rodrigo A
RA
Moreira-Filho
Carlos A
CA
Okamoto
Oswaldo K
OK
Carlotti
Carlos G
CG
D001254:Astrocytoma / Q000098:blood supply / Q000378:metabolism / Q000473:pathology*; D014408:Biomarkers, Tumor / Q000032:analysis*; D001932:Brain Neoplasms / Q000098:blood supply / Q000378:metabolism / Q000473:pathology*; D002352:Carrier Proteins / Q000096:biosynthesis*; D049109:Cell Proliferation; D016207:Cytokines / Q000096:biosynthesis*; D015870:Gene Expression; D020869:Gene Expression Profiling; D006801:Humans; D007150:Immunohistochemistry; D053208:Kaplan-Meier Estimate; D009389:Neovascularization, Pathologic; D009837:Oligodendroglioma / Q000098:blood supply / Q000378:metabolism / Q000473:pathology*; D020411:Oligonucleotide Array Sequence Analysis
D014408:Biomarkers, Tumor; D002352:Carrier Proteins; D016207:Cytokines; C066845:pleiotrophin