Charged nanoparticles compromise waste disposal unit, kills cancer cells
Cancer cells’ garbage disposal systems, or lysosomes, are particularly vulnerable to internal attacks as opposed to those of healthy cells. Lysosomes are tiny sacs packed with enzymes and acids that degrade unwanted parts of the cell, before either recycling or ejecting the waste components. Scientists from South Korea’s Institute of Basic Science (IBS) have found that a careful mix of charged nanoparticles, in a compromised lysosome, can deliver a fatal blow to cancer cells – such a lysosome releases its trash inside its cell and effectively kills the whole cell, over time.
“We have harnessed the deregulated waste management system of the cancer cells to act as a ‘nanoscale assembly line’ for constructing high-quality nanoparticle crystals that destroy the very lysosome ‘reactors’ that allowed them to grow in the first place,” explains IBS’ Bartosz A. Grzybowski.
The team experimented with different recipes for this novel form of therapy, finding that nanoparticles featuring 80% positively-charged and 20% negatively-charged ligands, including a pH-sensitivity on part of the negatively-charged ligands, were optimal for cancer cell selectivity. The nanoparticles form in clusters on the cancer cell surface, which then transform into tiny crystals inside the lysosomes and cause them to swell, deteriorate and die. The team’s nanoparticles proved effective in experiments on a range of cancer lines so far; they will see if this mixed-charge strategy could be effective against tumours in animal models.
Scientist Magdalena Borkowska said, “Our conclusions are based on a comparison of 13 different sarcomas, melanoma, breast and lung carcinoma cell lines with four non-cancer cell types – the nanoparticles were effective against all 13 cancer lines, while not harming non-cancerous cells.”
