Scientists have created tiny robots that can kill cancer cells in mice. These nanorobots have a special weapon that is only released in the area where the tumor is, leaving healthy cells unharmed.
A team of researchers at Karolinska Institutet in Sweden developed these nanorobots that kill cancer cells in mice. The weapon is concealed within a nanostructure and is activated only in the specific environment around the tumor, thus protecting healthy cells. The findings are detailed in the journal Nature Nanotechnology.
The research team at Karolinska Institutet had previously created structures capable of arranging what are called death receptors on cell surfaces, causing cell death. These structures consist of six peptides (chains of amino acids) arranged in a hexagonal pattern.
“The hexagonal nanopattern of peptides acts as a lethal weapon,” explained Professor Björn Högberg from the Department of Medical Biochemistry and Biophysics at Karolinska Institutet, who led the study. “If this were administered as a drug, it would inadvertently kill various cells in the body, which is not desirable. To solve this issue, we have concealed the weapon within a nanostructure made of DNA.”
Development of a ‘kill switch’
The technique of constructing nanoscale structures using DNA is known as DNA origami, a field Björn Högberg’s team has been focusing on for numerous years. In this study, they employed this method to create a ‘kill switch’ that activates when specific conditions are met.
“We have successfully concealed the weapon in a manner that enables its exposure only in the environment typically found in and around a solid tumor,” he elaborated. “This signifies the creation of a nanorobot that can precisely target and eliminate cancer cells.”
The crucial factor is the low pH, or acidic conditions that tend to surround cancer cells, which triggers the weapon on the nanorobot. Through cell studies conducted in test tubes, the researchers demonstrated that the peptide weapon remains hidden within the nanostructure at a normal pH level of 7.4 but exhibits a potent cell-killing action when the pH drops to 6.5.
Reduction in tumor growth
The team then tested the injection of these nanorobots into mice with breast cancer tumors. This led to a 70% reduction in the tumor growth rate as compared to mice receiving an inactive version of the nanorobot.
“The next step involves assessing whether this approach is effective in more advanced cancer models that closely mimic real human diseases,” said Yang Wang, the primary author of the study and a researcher at Karolinska Institutet’s Department of Medical Biochemistry and Biophysics. “We also need to evaluate the potential side effects of this method before it can be tested on humans.”
The researchers also aim to explore the enhancement of the nanorobot’s specificity by attaching proteins or peptides to its surface that specifically bind to certain types of cancer.
