Magnetically activated nanoparticles have been researched as a tool for killing tumors in the past, but generally the mechanism of action was using a magnetic field to resonate and heat up the nanoparticles and so kill the neoplasm. This can expose nearby healthy tissue to dangerous levels of heat, especially when the nanoparticles miss their cancer target. Researchers at Lund University in Sweden just reported in journal ACS Nano on a new method of using superparamagnetic iron oxide nanoparticles to coerce the tumor cells to kill themselves.
The team developed a special magnetic field generator that is able to spin the nanoparticles instead of making them vibrate. They attached a tumor seeking antibody to the nanoparticles and delivered them to tumor cells. Once inside, the magnetic field was activated to force the nanoparticles to turn back and forth, causing lysosomal membranes within the cell to break and release their payload. Since lysosomes contain everything necessary to break down biomolecules that make up the cell, the cancer cell dies from within while not causing any damage to nearby tissues.
Some details from the study abstract:
…we covalently conjugated SPIONs with antibodies targeting the lysosomal protein marker LAMP1 (LAMP1-SPION). Remote activation of slow rotation of LAMP1-SPIONs significantly improved the efficacy of cellular internalization of the nanoparticles. LAMP1-SPIONs then preferentially accumulated along the membrane in lysosomes in both rat insulinoma tumor cells and human pancreatic beta cells due to binding of LAMP1-SPIONs to endogenous LAMP1. Further activation of torques by the LAMP1-SPIONs bound to lysosomes resulted in rapid decrease in size and number of lysosomes, attributable to tearing of the lysosomal membrane by the shear force of the rotationally activated LAMP1-SPIONs. This remote activation resulted in an increased expression of early and late apoptotic markers and impaired cell growth.
Study in ACS Nano: Dynamic Magnetic Fields Remote-Control Apoptosis via Nanoparticle Rotation…
Lund University: NANOPARTICLES CAUSE CANCER CELLS TO SELF-DESTRUCT…