Zhonghua Kou Qiang Yi Xue Za Zhi. 2000 Mar; 35(2): 91-4.

[Experimental study on the influence of Gynostemma pentaphyllam Mak upon point mutation of Ha-ras oncogene in blocking leukoplakia from canceration]

Zhou Z, Tang G, Zhong W.

Department of Oral Medicine, School of Stomatology, Shanghai Second Medical University, Shanghai 200011, China.

OBJECTIVE: To study the influence of Gynostemma pentaphyllam Mak (GP) upon point mutation of Ha-ras oncogene the molecular mechanism of GP in blocking canceration, and the relationship between Ha-ras oncogene and canceration of leukoplakia. METHODS: DMBA induced carcinogeneses of the buccal pouch mucosa of the hamsters were divided into leukoplakia model group(LKG) and GP treated group(GPG). Point mutation (codon 61) of Ha-ras oncogene was detected by PCR-SSCP in both groups. RESULTS: The mutation incidence of LKG was 22.96%, while the mean incidence of GPG was 7.59% (The incidences of C20-OH group, glucoside group and aglucon group were 5.32%, 6.25% and 11.00% respectively). When treated with DMBA for 4 to 8 weeks, the mutation incidence of LKG ranged from 11.10% to 40.00%, while GPG ranged from 0 to 10.70%. CONCLUSIONS: GP has outstanding cancer blocking effect chiefly affected by free C20-OH. Mutation of Ha-ras oncogene plays an important role in leukoplakia canceration.