Jh. Cai et al., SMOOTH-MUSCLE TUMORS OF THE GASTROINTESTINAL-TRACT - EXPRESSION OF RAS P21 ONCOGENE PRODUCT AND THE ASSOCIATION WITH CLINICOPATHOLOGY, Chinese medical journal, 107(9), 1994, pp. 683-687
Quantitative analysis of ras oncogene product P21 was performed on par
affin blocks from 55 smooth muscle tumors of the gastrointestinal trac
t by immunofluorescence and flow cytometry, No positive evidence for P
21 was found in 5 caries of normal smooth muscle tissues. Eight of 14
leiomyomas were P21 positive (57%) but all of them were tower expresse
d with fluorescence index (FI) <1.25, whereas a total of 29 leiomyosar
comas and 12 potential malignant smooth muscle tumors were found to be
P21 positive (100%), and the majority were overexpressed with FI>1.25
(P<0.005). ras P21 was overexpressed significantly in the tumors with
mitotic counts of more than 1/10 high power field (P<0.005). It was a
lso overexpressed significantly as soon as the mild cytologic atypia o
f the tumor was found (P<0.005). Five-year survival rate was significa
ntly higher in the patients with lower-expression of ras P21 than thos
e with overexpression (P<0.005). It was suggested that the expression
of ras oncogene product P21 could be used as an objective parameter in
distinguishing malignants from benigns and predicting the prognosis o
f the patients with smooth muscle tumors of the gastrointestinal tract
.