[Methylation and expression analysis of p16(INK4a) and RB genes in meningiomas].
OBJECTIVE
To investigate the methylation of p16(INK4a) and RB gene, and the expression of p16(INK4a) in meningiomas.


METHODS
Methylation-specific polymerase chain reaction (MSP) was used to detect the methylation of p16(INK4a) and RB in 50 cases of meningiomas, and immunostaining was performed to analyze the protein expression of p16(INK4a) in 25 of those cases.


RESULTS
No methylation was found in the benign meningiomas, whereas methylation of p16(INK4a)or RB occurred in 6(37.5%) cases of grade II tumors and 4(28.6%) cases of grade III tumors, and among these cases, an atypical meningioma showed methylation of both genes. Thirteen cases showed p16(INK4a) positive expression, but none of them was methylated.


CONCLUSIONS
The methylation of p16(INK4a) or RB is related with the tumorigenesis and progression of atypical and anaplastic meningiomas, and a probable mechanism is that methylation causes the loss of expression and leads to dysfuncation of the p16(INK4a)/cyclin D1/CDK4/RB pathway.
Chen
Mi-na
MN
Department of Infectious Disease, West China Hospital, Sichuan University, Chengdu, Sichuan, 610041 PR China.
Mao
Qing
Q
Liu
Yan-hui
YH
Mao
Bo-yong
BY
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019938:Cyclin D1 / Q000235:genetics; D051358:Cyclin-Dependent Kinase 4; D018844:Cyclin-Dependent Kinases / Q000235:genetics; D019175:DNA Methylation; D005260:Female; D016161:Genes, Retinoblastoma; D019942:Genes, p16; D006801:Humans; D008297:Male; D008577:Meningeal Neoplasms / Q000235:genetics*; D008579:Meningioma / Q000235:genetics*; D008875:Middle Aged; D011518:Proto-Oncogene Proteins
D011518:Proto-Oncogene Proteins; D019938:Cyclin D1; C495900:CDK4 protein, human; D051358:Cyclin-Dependent Kinase 4; D018844:Cyclin-Dependent Kinases