A molecule that is a major ingredient in green tea can be used as a carrier for anticancer proteins, forming a stable and effective therapeutic nanocomplex. These findings, reported in a paper published online this week in Nature Nanotechnology, could help to build better drug-delivery systems.
Some cancer treatments depend on medication comprising the therapeutic drug and a carrier that delivers the drug to the tumour site. When designing drug carriers, several factors must be considered, for example, it must be specific so that it only attacks the tumour. Also, the drug-to-carrier ratio is important because using high quantities of the carrier could result in toxicity if the body cannot metabolize it. Furthermore, the complex will be ineffective if the body attacks and eliminates it too quickly.
Joo Eun Chung and colleagues used the molecule (-)-epigallocatechin-3-O-gallate (EGCG), which is found in high abundance in green tea, to create a carrier for the anticancer protein Herceptin. The advantage of EGCG over other carriers is that it also has anticancer effects. The authors injected the EGCG-Herceptin nanocomplex into mice and found that it demonstrated better tumour selectivity and growth reduction, as well as lasting longer in the blood - which could increase its efficacy - than if Herceptin was injected alone.