[Loss of heterozygosity of chromosome 1p/19q and p53 protein expression in oligodendroglioma].
OBJECTIVE
To study the status of loss of heterozygosity (LOH) of chromosome 1p/19q and p53 protein expression in oligodendroglioma, as compared to astrocytoma.


METHODS
One hundred and ninety-one cases of glioma of different histologic types and grades, including 116 cases of low-grade of oligodendroglioma (86 paraffin-embedded and 30 fresh tissues), 45 cases of anaplastic oligodendroglioma (all paraffin-embedded tissues) and 30 cases of astrocytoma of various grades (all paraffin-embedded tissues), were enrolled into the study. The LOH of chromosome 1p/19q was investigated by polymerase chain reaction (PCR)-based microsatellite analysis. The p53 protein expression was demonstrated by immunohistochemical staining.


RESULTS
The rates of 1p loss, 19q loss and 1p/19q loss were 69.8%, 64%, and 57.0% respectively in the 86 paraffin-embedded low-grade oligodendroglioma samples, as compared to 71.1%, 60.0% and 55.6% respectively in the 45 paraffin-embedded anaplastic oligodendroglioma samples. There was no difference of LOH of 1p/19q between low-grade oligodendroglioma and anaplastic oligodendroglioma (P>0.05). In the 30 cases of low-grade oligodendroglioma with fresh tissues available, the rates of 1p loss, 19q loss and 1p/19q loss were 70.0%, 63.3% and 60.0% respectively. The LOH of 1p/19q between paraffin-embedded and fresh samples was not statistically significant (P>0.05). In the 30 cases of astrocytoma, the rates of 1p loss, 19q loss and 1p/19q loss were 23.3%, 33.3% and 20.0% respectively, which were significantly less than those in oligodendroglioma (P<0.05). The expression of p53 protein was significantly lower in low-grade oligodendroglioma (8.1%) than in anaplastic oligodendroglioma (31.1%, P=0.007). The expression of p53 protein in oligodendroglioma was also lower than in astrocytoma (P=0.001). Furthermore, p53 protein expression negatively correlated with 1p/19q loss in anaplastic oligodendroglioma (P<0.05).


CONCLUSIONS
Both paraffin-embedded and fresh tissues are suitable for analysis of LOH of chromosome 1p/19q. Oligodendroglioma demonstrates a higher frequency of LOH of chromosome 1p/19q and lower expression of p53 protein than astrocytoma. The LOH of chromosome 1p/19q negatively correlates with the expression of p53 protein. These parameters have both diagnostic and prognostic values.
Department of Pathology, Shanghai Medical College of Fudan University, and Department of Neuropathology, Huashan Hospital, Shanghai 200032, China.
Ji
J
Xiong
Ying
Y
Liu
Chao
C
Li
Jing-jing
JJ
Zhu
Zhu-rong
ZR
Ye
Ying
Y
Mao
Yin
Y
Wang
D000293:Adolescent; D000328:Adult; D000368:Aged; D001254:Astrocytoma / Q000235:genetics / Q000378:metabolism; D001932:Brain Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D002648:Child; D002878:Chromosomes, Human, Pair 1; D002888:Chromosomes, Human, Pair 19; D005260:Female; D006801:Humans; D019656:Loss of Heterozygosity; D008297:Male; D008875:Middle Aged; D009837:Oligodendroglioma / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D016612:Paraffin Embedding; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism*; D055815:Young Adult
D016159:Tumor Suppressor Protein p53