竹内 浩明 福井医科大学, 医学部, 助手 (80262624)
佐藤 一史 福井医科大学, 医学部・附属病院, 講師 (60187177)
兜 正則 福井医科大学, 医学部・附属病院, 講師 (80169599)
小寺 俊昭 福井医科大学, 医学部, 助手 (10283178)
SATO Kazufumi Neurosurgery, Fukui Medical University, Assistant Professor
KODERA Toshiaki Neurosurgery, Fukui Medical University, Senior Staff
|Budget Amount *help
¥2,100,000 (Direct Cost : ¥2,100,000)
Fiscal Year 1997 : ¥100,000 (Direct Cost : ¥100,000)
Fiscal Year 1996 : ¥2,000,000 (Direct Cost : ¥2,000,000)
Small roundish cell cluster surrounding In the neuronal cells (satellltosis) Is frequently seen in the peripheral area of gIlomas. In thIs study, we examined 77 cases of surgically resected human gllomas, and satellltotic cells (SC) were observed In 22 cases (30%). SC were frequently seen in lower grade tumors(3casesinGradelV (1O%), 8 cases in Grade III(25%), lO cases in Grade II(70%). Immunoreactivity for GFAP, MBP, p53, bci.2, p16, KI-67, PCNA In SC were examined. More than 80% of SC were positive reaction for GFAP, and negative for MBP.immunopositivity rate for p53 and bcl-2 was less than 1%. P16 immunopositivity in SC was approximately10%. Labeling indices (LI) of Ki-67 and PONA were less than 1% even in the grade IV tumors. Although p53 gene mutation was detected in 25% of the tumors, there was no relationship between the mutation rate and immunopositive rate for p53 protein In SC.Homozygous deletion of p16 gene was detected in 30% of grades III and IV tumors by Southern blotting. The deletion was frequently seen In the malignant phenotype, and the immunopositivity rate for p16 protein was In inverse proportion to the frequency of gene deletion.
Ultrastructurally, abundant mitochondria and small amount of Intermediate fllaments were seen in the cytoplasm of SC.These results suggest that SC have an astrocytlo nature. Low LI in SC suggest that these cells do not always have malignant potential, and the possibility that they might act asto protect the neuronal cells. C6 glloma cells were implanted to the rat brain (10 cases), and we examined them by the same methods as described above. SC were detected In 7 (70%) rat tumor models, and immunohistochemical and ultrastructural results were compatible with those in human gllomas.