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

Area of Science:

• Phytochemistry
• Molecular Biology
• Cancer Research

Background:

• Ginkgo biloba leaf extracts possess antioxidant and anti-lipoperoxidative properties attributed to flavonoid and terpenoid compounds.
• Extracts exhibit anti-angiogenic activity, potentially via antioxidant effects and inhibition of nitric oxide synthase.
• Previous research suggests potential chemopreventive roles for Ginkgo biloba.

Purpose of the Study:

• To investigate the anticancer (chemopreventive) properties of Ginkgo biloba leaf extracts.
• To elucidate the molecular mechanisms underlying the anticancer effects, including antioxidant, anti-angiogenic, and gene-regulatory actions.
• To assess the role of specific constituents like ginkgolide B in cancer cell inhibition.

Main Methods:

• Utilized molecular, cellular, and whole animal models.
• Performed cDNA microarray analyses to study gene expression changes in cancer cells.
• Assessed inhibition of proliferation in human breast cancer cell lines and xenografts.
• Evaluated effects on radiation-induced clastogenic factors and UV-induced oxidative stress in humans.

Main Results:

• Ginkgo biloba extract and ginkgolide B inhibited proliferation of aggressive human breast cancer cells and xenografts.
• Gene expression analysis revealed altered regulation of cell proliferation, differentiation, and apoptosis.
• Extracts demonstrated adaptive transcriptional responses in bladder cancer cells, enhancing antioxidant status and inhibiting DNA damage.
• In humans, extracts reduced radiation-induced clastogenic factors and UV-induced oxidative stress.

Conclusions:

• Ginkgo biloba leaf extracts exhibit multifaceted anticancer properties, including antioxidant, anti-angiogenic, and gene-regulatory effects.
• Flavonoid and terpenoid constituents likely act synergistically to inhibit carcinogenesis-related processes.
• The findings support the potential of Ginkgo biloba extracts as a chemopreventive agent, with total extracts potentially offering optimal efficacy.