[Point mutations of N-ras oncogene and abnormal expression of rasp21, p53 proteins in orbital rhabdomyosarcoma].
OBJECTIVE
The point mutations of N-ras oncogene and the abnormal expression of rasp21 and p53 proteins in orbital rhabdomyosarcoma (RMS) were analyzed in order to explore the role of oncogene mutations in the pathogenesis of orbital RMS and its relation to patients' prognosis.


METHODS
21 human orbital RMS tissues were analyzed by dot-blot hybridization and immunohistochemistry using synthetic specific oligonucleotide probes and mutant rasp21, p53 monoclonal antibodies.


RESULTS
The second base mutation of codon 12 of the N-ras oncogene was found in 4 patients. The third base mutation of codon 61 was found in 5 patients. The mutant rate was 33.3%. By immunohistochemistry analysis, the overexpression of rasp21 and p53 protein level was found in 42.9% and 76.2% respectively. The prognosis of patients with overexpression of ras p21, p53 was worse than that of normal expression (P < 0.01).


CONCLUSIONS
The mutants of ras and p53 oncogene play important roles in the pathogenesis of orbital RMS, and the abnormal expression of their protein products is related to patients' prognosis.
Zhang
H
H
Department of Ophthalmology, The Second Teaching Hospital, Tianjin Medical University, Tianjin 300211, China.
Song
G
G
Zhang
S
S
Chang
J
J
Zhang
W
W
Yu
H
H
D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D005260:Female; D011905:Genes, ras / Q000235:genetics*; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D015689:Oncogene Protein p21(ras) / Q000096:biosynthesis*; D009918:Orbital Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D017354:Point Mutation; D012208:Rhabdomyosarcoma / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D016159:Tumor Suppressor Protein p53 / Q000096:biosynthesis*
D016159:Tumor Suppressor Protein p53; D015689:Oncogene Protein p21(ras)