Prognostic value of loss of heterozygosity around three candidate tumor suppressor genes on chromosome 10q in astrocytomas.
We thoroughly examined loss of heterozygosity (LOH) around three candidate tumor suppressor genes on chromosome 10q to determine whether LOH of each tumor suppressor gene is associated with the previously defined clinical prognostic indices. We also examined whether LOH can help predict prognostic variables in astrocytomas. We selected samples from 40 astrocytomas (grades 2-4), performed Ki-67 immunostaining, and counted positive cells. Using DNA from aliquots of tumor blocks and leukocytes, we investigated LOH around the PTEN, NEURL, and DMBTI genes (10q23.3-26.1) with the silver staining procedure. We then statistically evaluated the relationship among histological features, regional LOH on chromosome 10q, and survival. The mean survival period for patients with LOH around PTEN was 7.2 months after surgery, while that for patients without LOH around PTEN was 21.4 months. Thus, LOH around PTEN was closely associated with a reduced overall survival (p = 0.0020) but LOH at NEURL or DMBTI was not (p > 0.05). The combined features of an increase in histological grading and Ki-67-positive cells and the presence of LOH around PTEN significantly correlated with poor prognosis. These factors may be useful predictors of survival, and LOH analysis of tumor suppressor genes on chromosome 10q can contribute greatly to the treatment of patients with astrocytoma.
Terada
Kinya
K
Department of Neurological Surgery, Graduate School of Medicine and Dentistry, Okayama University, Japan.
Tamiya
Takashi
T
Daido
Shigeru
S
Kambara
Hirokazu
H
Tanaka
Hiroaki
H
Ono
Yasuhiro
Y
Matsumoto
Kengo
K
Ito
Sachio
S
Ouchida
Mamoru
M
Ohmoto
Takashi
T
Shimizu
Kenji
K
D000368:Aged; D000369:Aged, 80 and over; D001254:Astrocytoma / Q000235:genetics* / Q000473:pathology; D001932:Brain Neoplasms / Q000235:genetics* / Q000473:pathology; D005260:Female; D016147:Genes, Tumor Suppressor; D005909:Glioblastoma / Q000235:genetics* / Q000473:pathology; D006801:Humans; D019656:Loss of Heterozygosity; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D016019:Survival Analysis