Chemotherapy medications can be finicky when attacking cancers, showing efficacy but often not enough to subdue the disease. A team of researchers from UC Santa Barbara, South Korea’s Pusan National University, and Genentech decided to investigate whether changing the shape of the individual drug particles would improve their effectiveness.
They created rod shaped nanoparticles of camptothecin and coated it with trastuzumab, an antibody that clings to certain cancer cells. To everyone’s delight, the combination proved to be 10 times more effective at disrupting breast cancer cell growth than traditional camptothecin or 10,000 times than trastuzumab alone.
Conventional anti-cancer drugs accumulate in the liver, lungs and spleen instead of the cancer cell site due to inefficient interactions with the cancer cell membrane,” explained Samir Mitragotri , professor of chemical engineering and Director of the Center for BioEngineering at UCSB. “We have found our strategy greatly enhances the specificity of anti-cancer drugs to cancer cells.”
Mitragotri and collaborators at UCSB, including post-doctoral researchers Sutapa Barua and Jin-Wook Yoo, and former graduate student Poornima Kolhar, looked to human breast cancer cells to examine how shape works in synergy with molecular recognition to perform complex tasks within the human body.
“We were inspired to look at the shape as a key parameter by natural objects. In nature, all key particles such as viruses, bacteria, red blood cells, platelets are non-spherical,” said Mitragotri. “Their shape plays a key role in their function.”
Study in PNAS: Particle shape enhances specificity of antibody-displaying nanoparticles
Press release: Changing Shape Makes Chemotherapy Drugs Better at Targeting Cancer Cells