One of the challenges of chemotherapy for cancer is how drugs are delivered. Conventional drugs are often given through an IV, and as they travel around the body through the blood, they can affect other healthy tissues, reducing the drug’s effectiveness and causing harmful side effects. To overcome this challenge, researchers have developed nanoparticles, molecules that can be 1,000 times smaller than a red blood cell, to specifically target unique markers on cancer cells.
Nanoparticles are used in advanced imaging techniques to show where cancer cells are located in the body, but they can also be used in cancer treatment. A nanoparticle can act as a high-tech delivery system, pairing a cancer-targeting “homing molecule” with a cancer-fighting drug.
A team of researchers recently published a study investigating whether a newly designed therapy that uses nanoparticles is effective for treating some hard-to-treat forms of cancer, including rare subtypes of thyroid cancer and pancreatic cancer. Their promising results add to the growing body of evidence that nanoparticles could become an important part of future cancer therapies.
Two-part nanoparticle delivers cancer drug to tumours
The researchers studied anaplastic thyroid cancer, a rare and aggressive subtype of thyroid cancer, and pancreatic neuroendocrine tumours (pNETS). Both of these forms of cancer often do not shrink when treated with current cancer drugs.
Evidence suggests that blood vessels that grow around tumours and supply it with nutrients can also stop drugs from getting to the tumour where they can have an effect.
In this study, the researchers developed a specialized nanoparticle with 2 tumour-fighting parts: a targeting molecule and a cancer drug. The targeting molecule locates tumour blood vessels, attaching to and damaging them. With the blood vessels damaged, the drug paclitaxel, which is currently used to treat a number of different types of cancer, can then attack the tumour cells more effectively.
When they tested this combination nanomedicine in mice with anaplastic thyroid cancer and pNETs, they found that it was more effective at locating and eliminating tumours than either paclitaxel alone or the targeted molecule alone. Importantly, the researchers found that the nanoparticle specifically located and delivered the drug only to cancer cells without affecting healthy tissues.
Precise delivery mechanism can avoid harmful side effects
Chemotherapy drugs can be very effective to fight tumours, but their use is often limited by the harmful effects that they can have on healthy tissues. A targeted nanomedicine that can deliver the cancer drug directly to the tumour tissue, such as the combination nanoparticle used in this study, would minimize toxic side effects while allowing higher doses to be given to maximize effectiveness.
While the nanoparticle developed in this study was used to treat 2 rare forms of cancer, the researchers suggest that this treatment does not depend on specific genetic mutations or cancer types and could be adapted to treat a broad range of cancers.
Eileen Hoftyzer, BSc