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Sustancias naturales que inhiben la angiogénesis: una fuente potencial para la investigación de nuevos agentes para tratar el cáncer

Un enfoque integrativo para tratar a los pacientes con cáncer debe tener como objetivo las vías múltiples bioquímicas y fisiológicas que favorecen el desarrollo del tumor y deben asimismo minimizar la toxicidad en tejidos sanos. La angiogénesis es un proceso clave en el desarrollo del cáncer. Muchos agentes naturales que inhiben la angiogénesis manifiestan también otras actividades anticancerosas. Este artículo se centra en los productos que tienen una gran actividad antiangiogénica como: Artemisia annua (Chinese wormwood), Viscum album (European mistletoe), Curcuma longa (curcumina), Scutellaria baicalensis (Chinese skullcap), resveratrol y proantocianidina (extracto de pepita de uva), Magnolia officinalis (árbol de magnolia china), Camellia sinensis (té verde), Ginkgo biloba, quercetina, Poria cocos, Zingiber officinalis (gengibre), Panax ginseng, Rabdosia rubescens hora (Rabdosia), y algunas hierbas chinas. Este artículo también describe algunas de las otras acciones de estos agentes que pueden inhibir la progresión tumoral y reducir el riesgo de metástasis.

Curr Oncol. 2006 Feb;13(1):14-26.Natural health products that inhibit angiogenesis: a potential source for investigational new agents to treat cancer Sagar SM, Yance D, Wong RK. Juravinski Cancer Centre and McMaster University (Department of Medicine), Hamilton, Ontario.

An integrative approach for managing a patient with cancer should target the multiple biochemical and physiologic pathways that support tumour development and minimize normal-tissue toxicity. Angiogenesis is a key process in the promotion of cancer. Many natural health products that inhibit angiogenesis also manifest other anticancer activities. The present article focuses on products that have a high degree of anti-angiogenic activity, but it also describes some of the many other actions of these agents that can inhibit tumour progression and reduce the risk of metastasis. Natural health products target molecular pathways other than angiogenesis, including epidermal growth factor receptor, the HER2/neu gene, the cyclooxygenase-2 enzyme, the nuclear factor kappa-B transcription factor, the protein kinases, the Bcl-2 protein, and coagulation pathways. The herbs that are traditionally used for anticancer treatment and that are anti-angiogenic through multiple interdependent processes (including effects on gene expression, signal processing, and enzyme activities) include Artemisia annua (Chinese wormwood), Viscum album (European mistletoe), Curcuma longa (curcumin), Scutellaria baicalensis (Chinese skullcap), resveratrol and proanthocyanidin (grape seed extract), Magnolia officinalis (Chinese magnolia tree), Camellia sinensis (green tea), Ginkgo biloba, quercetin, Poria cocos, Zingiber officinalis (ginger), Panax ginseng, Rabdosia rubescens hora (Rabdosia), and Chinese destagnation herbs. Quality assurance of appropriate extracts is essential prior to embarking upon clinical trials. More data are required on dose-response, appropriate combinations, and potential toxicities. Given the multiple effects of these agents, their future use for cancer therapy probably lies in synergistic combinations. During active cancer therapy, they should generally be evaluated in combination with chemotherapy and radiation. In this role, they act as modifiers of biologic response or as adaptogens, potentially enhancing the efficacy of the conventional therapies.