Scientists create a cancer drug using a multi-component supramolecular system known to self-assemble at the nanoscale level. The drug is designed to gobble up cancer cells.
Supermolecular System
A supramolecular system is characterized by a chemical structure comprised of smaller molecules that self-organize together to form well-defined and more complex molecules. The resulting molecules are bonded like building blocks, similar to how tiny LEGO pieces are put together to form larger pieces.
The newly designed drug has a bi-functional or "one-two punch" approach against cancer. First, it triggers the macrophage, the largest immune cells in the body and second, it stops the other cells that aid the growth of cancer tumors.
The international team of scientists reported success in the first stage of preclinical trials. The drug now has a license and the team hoped for the fast approval process.
Macrophages
The drug will work primarily by enhancing the action of the white blood cells or the macrophages. These cells work by eating up all unwanted intruders in the immune system.
With its main function as the body's "big eaters," macrophage is the body's frontline against infections brought by viruses or bacteria. Macrophage cells have two types: the M1 cells and the M2 cells.
The M1 activates the immune system as soon as it encounters a threat. The M2 subsequently relieves the ensuing inflammation which resulted from the immune system's fight against the threat.
The M1 and M2 effectively work in tandem. However, cancer cells can deceive them by sending a "don't eat me" signal to M1, and then by convincing M2 that they were harmless enough for M2 to join them. Once M2 allows itself to be tricked by the cancer cells, it willingly can help them grow.
Now, the team of scientists from the University of Massachusetts Amherst, the Harvard Medical School, and the Brigham and Women's Hospital designed the drug to make it impossible for cancer cells to deceive the macrophages.
'One-Two Punch' of Self-Assembling LEGO-Like 'Supramolecular' Drug
In designing the drug, the team creates a supramolecule that initially could block the "don't eat me" deceptive signals that cancer cells produce, and then prevents M2 from reacting.
"This is the first time anyone has combined these two, a drug that targets M2 macrophages and an antibody that inhibits 'don't eat me signal,' in one delivery system," said Ashish Kulkarni, the co-corresponding author for the study.
The drug has been tested in mice with melanoma and breast cancers. The result of the trial detailed in the journal Nature Biomedical Engineering on July 2 showed that mice treated with the supramolecular drug had successfully prevented the tumor growth.
The trial also showed an increase in survival among the mice. There had also been a significant decrease in their metastatic nodes.
"We can actually see macrophages eating cancer cells," said Shiladitya Sengupta, co-author of the study.
His insight was based on microscopy images that show macrophages gobbling up the cancer cells.
The team's next step is to continue testing the drug in several other preclinical setups to assess its safety and efficacy. They would also like to estimate the accurate dosage for the drug. Hopefully, the team can move on from preclinical trials to clinical trials.