JAN 20, 2016 12:47 PM PST

Path of Chemo Drugs Now Lit by New Peptide Tags

Fluorescent peptide tags light the path of chemo drugs

When x-ray radiation fails or when complete surgical removal is not possible, chemotherapy is the next best available option to treat cancer cells. Although the treatment can be highly potent, doctors have limited knowledge of where the drug ends up once it is administered to the patient. To solve this problem, researchers from Ohio State University (OSU) have devised a way to tag anti-cancer drugs and follow its path in real time.
Tracking anti-cancer drugs in the patients has been attempted before. However, these attempts have been thwarted because organic tracker dyes dissolved too quickly before reaching the targets. Conversely, other longer-lasting tracker molecules were too toxic for the body to be of clinical use.
Led by Dr. Mingjun Zhang, biomedical engineering professor at OSU, the research team created a new nanoparticle tracking technology that is based on naturally occurring small peptide molecules. To the nanoparticle, the team attached a fluorescent tag that can be optically detected only once the drug is active in the body.
The real innovation in this new design lays in the “inherent biocompatibility” of the florescent nanoparticle. Because it is made from amino acids, the peptide causes little to no harm to the body’s cells. Furthermore, once the peptides have served its tracking purpose, the body is able to process it easily.
Testing the technique on doxorubicin, a commonly prescribed chemotherapy drug, the researchers noted that the fluorescence signal could be detected over long periods. Tracking this and other chemotherapy drugs could allow doctors to measure the speed and efficacy of a drug inside a patient. And because the fluorescence signal is only detectable once the drug is active, doctors can clearly trail the drug’s path and time its release.
As with any drug compounds, chemotherapy drugs can have different behavioral profiles in different patients. “In some people, chemotherapy can take effect in a few minutes, in others it can take hours, and there are also cases where it never takes effect,” says Prof. Zhang.
In the case of cancer, knowing when and where the drug acts is especially crucial, considering the fact that chemotherapy drugs are actually highly poisons to the body’s cells. Chemotherapy drugs target rapidly dividing cells and kills most cancerous cells. Unfortunately, most drugs can’t yet discriminate between cancer cells and healthy cells, so patients often experience “collateral damages” – negative side-effects from the therapy.
The ability to track the chemo drug in real time could greatly expand our understanding of where the drugs land and how they affect the patient, positively and negatively. The tracking technology could also be combined with targeted chemotherapies currently being developed, allowing researchers to truly minimize the collateral damages inflicted on cancer patients.

Additional source: MNT
About the Author
Doctorate (PhD)
I am a human geneticist, passionate about telling stories to make science more engaging and approachable. Find more of my writing at the Hopkins BioMedical Odyssey blog and at TheGeneTwist.com.
You May Also Like
Loading Comments...
  • See More