Whenever someone gets sick, they need some form of treatment. Treatment can be a natural remedy or, most likely, a drug. In the case of more serious illnesses such as cancer, the only treatment is medicine. Medicine has been used to treat illness for most of the modern age, and you are probably familiar with many drugs. Have you ever wondered how those drugs work?
Close but no cigar.
A lot of anti-cancer drugs rely on clathrin-dependent receptor-mediated endocytosis. Now, that might sound a little complicated, but I’m going to break it down for you. Clathrin is a kind of coating protein for vesicles, little balloon-like sacs that allow different substances to enter a cell. These vesicles are created from the cell’s membrane after the target substance’s ligand binds to a receptor. Once the receptor binds a ligand, a vesicle is created, and the substance enters the cell within the vesicle. This is called receptor-mediated endocytosis. Neat, right?
Two of these ligands are transferrin and riboflavin. Transferrin binds iron and is a good target for drug delivery. Because transferrin travels across the blood brain barrier to deliver iron to the brain, it can be used to ferry drugs through the blood brain barrier to treat diseases that target the brain. Riboflavin is another important ligand for drug delivery. Early data suggests that riboflavin could be beneficial in drugs targeting breast cancer. The carrier protein that binds riboflavin has been found in increased levels in cancerous breast tissue, so the drug would have an easier time finding the tumor.
Receptor-mediated endocytosis is essential to many cell functions. Because of its necessity, it is very useful for drug delivery. New drugs are being developed every year, and, soon, we may have a easy way to fight cancer.
Bareford, Lisa M and Peter W Swaan. “Endocytic mechanisms for targeted drug delivery” Advanced drug delivery reviews vol. 59,8 (2007): 748-58.