By Edwin L. Aguirre
In the past decade, nanotechnology has become an important tool in the fight against breast cancer. Using nanoparticles measuring only billionths of a meter in size, doctors are able to deliver drug molecules directly to the affected tissue.
“A nanoparticle-based drug called Abraxane is being used in clinics worldwide to treat breast cancer patients,” says chemical engineering
Asst. Prof. Prakash Rai. “However, the disease continues to be a major health concern.”
Breast cancer is one of the leading causes of cancer deaths among women in the United States. According to the U.S. Centers for Disease Control and Prevention
, in 2013 nearly 231,000 women were diagnosed with the disease, and close to 41,000 died from it. “There is a dire need for better, more effective treatments with lower side effects,” says Rai.
Common side effects of chemotherapy include nausea, weakened immune system and loss of weight, appetite and hair. Some side effects can be life-threatening, such as hypersensitivity reactions and decreasing white blood cell count.
Rai was awarded a grant by the National Cancer Institute at the National Institutes of Health (NCI/NIH) totaling more than $725,000 to study a combined, nanotechnology-based diagnostic/therapeutic strategy for the targeted treatment of two subtypes of breast cancer: the human epidermal growth factor receptor 2 positive (HER2+)
and the triple-negative breast cancer (TNBC).
“HER2-positive and TNBC are among the most difficult types of breast cancer to treat, with resistance to primary treatments a major issue in patients with recurring disease,” notes Rai.
The Emerging Field of Theranostics
Theranostics, a combination of therapeutics and diagnostics, is a relatively new field in medicine that helps doctors decide the best therapy to prescribe for each patient. Instead of a broad, generic approach to treatment, this personalized medicine ensures the patient will receive only the drug he or she actually needs, thereby maximizing the therapeutic benefits while minimizing unwanted adverse side effects.
Rai and his research team combined several therapeutic agents that have shown potential in cancer treatment into a single nanometer-sized targeted drug-delivery platform — called a “theranostic nanoconstruct,” or TNC — and tested the nanoplatform’s treatment effectiveness in lab mice.
“The combination of these therapeutic agents with an imaging agent into one TNC helps reduce the dose required in a patient to achieve efficacy, thus reducing the toxic side effects,” explains Rai.
He says the imaging agent helps the team locate the TNCs and track them after they have been injected into the body, leading researchers to the cancerous tissues.
“Targeting the TNCs specifically to cancer cells helps reduce collateral damage to healthy, normal cells,” notes Rai. “If successful, these image-guided, targeted therapies should make a significant impact on the clinical care of breast cancer patients by improving survival and overall quality of life.”