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compound. The highest levels of lignans are found in the seeds, the part of the plant I use most frequently. Methanol extracts of burdock seed have induced differentiation of myeloid leukemia cells and demonstrated potent anticancer action against lymphocytic leukemia. 31,32
Gene Repairing, Enzyme Inhibitors, and Cytotoxic Herbs
These herbs have more direct anticancer and/or antitumor effects. They are capable of inducing cell death by selectively removing cells in which DNA has been damaged.
These are herbs that either increase the innate immunity and cytotoxicity of one's immune system, or have direct antitumor/antineoplastic activity. The most common antitumor active principals found in plants are terpenes and alkaloids.
Gene repairing is a mechanism in which some plant compounds genetically alter cancerous cells to revert back to normal cells, possibly by inhibiting cell division through means of a DNA repair mechanism or by extinguishing the malignant information that can eventually kill the cancerous cell. One known mechanism by which plants can genetically affect cell proliferation of preneoplastic cells is by inhibiting certain enzymes that promote cancer growth. Two such enzymes are tyrosine 3, which is a crucial enzyme involved in the promotion of many cancers, including melanoma, and ornithine decarboxylase (ODC). ODC as well as other cancer-promoting enzymes trigger mitogen-activated protein (MAP) kinase activity, which in turn implies a proportional increase in tumor invasiveness.
Genes involved in the invasive and metastatic phenotype of cancer cells are potential candidates to serve as markers of tumor aggressiveness. The interaction between cancer cells and laminin, a major basement membrane glycoprotein, is considered a determining event in tumor progression. Among the several cell-surface proteins that are able to interact with laminin, the 67-kd laminin receptor (67LR) is involved in the chemotactic migration of malignant cells toward laminin. Compared to a normal tissue counterpart, 67LR expression is increased in a variety of human cancers, including breast, prostate, colon, gastric, ovarian, endometrial, lung, thyroid, and hepatocellular carcinoma; furthermore, this increase in 67LR is also associated with the biologic

 
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