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| CAMs are complex protein and carbohydrate molecules that occur on the plasma membranes of all cell surfaces. They control both intracellular and extracellular (cell-to-cell communication. CAMs regulate organ architecture, cell migration, differentiation, apoptosis, mitosis, platelet aggregation, and the activity of the immune system. |
| There are three types of CAMs: |
| 1. Cadherins. Cadherins inhibit both invasion and metastasis and reduce the expression of tumor cells. A well-known cadherin, E-cadherin, is strengthened by tangeretin, a flavone found in tangerines. |
| 2. Cell-surface lectins. Lectins bind to the tumor cell and inhibit tumor cell-to-cell adhesion, thereby prohibiting completion of the metastatic process. A lectin called galactose is found abundantly in modified citrus pectin (MCP). MCP has been shown to inhibit rumor formation and growth in a number of cancers, including prostate cancer. 17 |
| 3. Proteoglycans (PGs) and glycosaminoglycans (GAGs). PGs, proteins that form a major component of connective tissue, are attached to large carbohydrates called GAGs. GAGs are part of the extracellular matrix that forms such tissues as cartilage. Because they have a strong negative charge, GAGs are able to bind to many substances. Good sources of GAGs include glucosamine sulfate, cartilage (both bovine and shark), and hyaluronic acid. Hyaluronic acid offers major help in protecting the extracellular matrix (the "glue" that holds cells together), thereby acting as a defense against cancer's invasion. |
| Cancer-Cell Receptors |
| Cancer-cell receptors serve as a link between the extracellular environment and the cell nucleus. Signals are transmitted from the cell surface to the cell material (cytoplasm) and then to the nucleus. One such cell receptor is referred to as tyrosine kinase. The extracellular portions of the tyrosine kinase binds to specific ligands (sort of sticky-substance docking stations for intercellular messages). Ligand binding is followed by a process that leads to the activation of the receptor. A cascade of signaling events then takes place, causing cellular mutation, oncogene transformation, and tumor development. |
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