Ginkgo biloba extracts and cancer: a research area in its infancy

Abstract

Recent studies conducted with various molecular, cellular and whole animal models have revealed that leaf extracts of Ginkgo biloba may have anticancer (chemopreventive) properties that are related to their antioxidant, anti-angiogenic and gene-regulatory actions. The antioxidant and associated anti-lipoperoxidative effects of Ginkgo extracts appear to involve both their flavonoid and terpenoid constituents. The anti-angiogenic activity of the extracts may involve their antioxidant activity and their ability to inhibit both inducible and endothelial forms of nitric oxide synthase. With regard to gene expression, a Ginkgo extract and one of its terpenoid constituents, ginkgolide B, inhibited the proliferation of a highly aggressive human breast cancer cell line and xenografts of this cell line in nude mice. cDNA microarray analyses have shown that exposure of human breast cancer cells to a Ginkgo extract altered the expression of genes that are involved in the regulation of cell proliferation, cell differentiation or apoptosis, and that exposure of human bladder cancer cells to a Ginkgo extract produced an adaptive transcriptional response that augments antioxidant status and inhibits DNA damage. In humans, Ginkgo extracts inhibit the formation of radiation-induced (chromosome-damaging) clastogenic factors and ultraviolet light-induced oxidative stress - effects that may also be associated with anticancer activity. Flavonoid and terpenoid constituents of Ginkgo extracts may act in a complementary manner to inhibit several carcinogenesis-related processes, and therefore the total extracts may be required for producing optimal effects.

Apoptotic and anti-angiogenic effects of Pulsatilla�koreana extract on hepatocellular carcinoma

“…As in this point, inhibition of tumor growth by PKE seems to affect angiogenic factors such as VEGF. Indeed, natural products including green tea and ginkgo biloba extracts have been reported to show anti-angiogenesis effect through inhibition of VEGF (22,23). In addition, the in vivo anti-angiogenic effects of PKE was supported by decreased expression of CD34, a microvessel endothelial cell marker, in a VEGF-mediated Matrigel plug assay in parallel with inhibition of HUVEC cell migration and tube formation, indicating that PKE inhibited angiogenesis through not only VEGF but also targeting endothelial cells directly.…”

Antitumor effect of Careya arborea against Ehrlich ascites carcinoma with reference to lipid peroxidation and enzymatic and non enzymatic antioxidant system in Swiss albino mice

“…Plant derived natural products such as flavonoids, terpenoids and steroids etc. have received considerable attention in recent years due to their diverse pharmacological properties including antitumor and antioxidant activity (DeFeudis et al, 2003;Takeoka and Dao, 2003). There has been growing interest in the analysis of certain flavonoids, triterpenoids and steroids stimulated by intense research in to their potential benefits to human against infection and degenerative diseases.…”

Hepatoprotective Activity of Indian Medicinal Plant on Ccl4 Induced Liver Damage in Wistar Rats

“…Evaluation of Hepato-protective activity [17][18][19][20] CCl4 induced hepatotoxicity in rats models was used for evaluation of hepatoprotective activity for plant extract. The experimental design was as follows (Table No.1).…”