GLOBAL CHALLENGES

Cancer Treatment Advances with Nanotech

Rebecca Kutzer-Rice | Date: 07-06-10 | Comments

Scientists have added carbon nanotubes to existing chemotherapy drugs in an effort to alleviate dangerous side effects while making the treatment more effective.

With cancer incidences increasing at alarming rates, research toward effective treatment has become critical. While current methods, like radiation and chemotherapy, can help mitigate cancer, these treatments have severe drawbacks. Researchers from Harvard University are using nanotechnology to develop a technique to improve chemotherapy�making it more effective while reducing the dangerous side effects of today�s treatments.

One of the most powerful and widely used chemotherapy drugs is the 40-year-old cisplatin, which is used to treat cancers like lymphoma, sarcoma, and lung and ovarian cancer. When administered intravenously, the drug releases toxic platinum atoms. Cisplatin is deadly, not only to cancer cells but also to healthy cells. It can cause damage to the nerves, hearing loss and infertility. The most dangerous effect of cisplatin is nephrotoxicity�damage to the kidneys that can lead to death. Because of these risks, the drug cannot be given in higher doses, which would be even more successful in killing cancer.

Cisplatin, whose structure is pictured here, is highly effective in treating cancer but has potentially deadly side effects.

Researchers at Harvard, including Assistant Professor Shiladitya Sengupta, set out to increase the drug�s safe dosage by reducing its absorption in the kidney. Because the kidney can only absorb particles smaller than 5 nanometers wide, fashioning larger drug particles was paramount in the study.

The scientists created a large polymer by threading cisplatin molecules onto strings of carbon nanotubes. The polymer rolled up into a molecule 100 nanometers in size, 20 times larger than particles that can enter the kidney, lungs, liver and other organs. The high acidity of cancerous tumors causes the molecule to dissolve and deposit the toxic medication onto the cancerous cells.

�It showed absolutely minimal toxicity to the kidney,� states Sengupta, according to the Harvard press release.

Although the technology has only been tested on animals, it has proved effective in treating lung, breast and ovarian cancers. It will require extensive human testing before being used as a mainstream cancer treatment.

The project received funding from National Institutes of Health and the Defense Department�s Breast Cancer Research Program. Other researchers were from Brigham and Women�s Hospital; the University of Notre Dame; the Harvard-MIT Division of Health Sciences and Technology; the Dana-Farber Cancer Institute; the National Chemical Laboratory in Pune, India; and the Translational Health Science and Technology Institute in New Delhi.