Nano-pPAAM --- 'Trojan Horse' Approach
Hi friends, just adding this topic here - after came across it few days ago:
NTU Singapore scientists devise 'Trojan horse' approach to kill cancer cells without using drugs
Published on: 23 Sep 2020
Seeking to exploit the amino acid dependency of cancer cells but avoid the challenges of strict dietary regimes, the NTU researchers devised a novel alternative approach.
They took a silica nanoparticle designated as 'Generally Recognized As Safe' by the US Food and Drug Administration and coated it with L-phenylalanine, and found that in lab tests with mice it killed cancer cells effectively and very specifically, by causing them to self-destruct.
The anti-cancer therapeutic nanoparticle is ultrasmall, with a diameter of 30 nanometres, or approximately 30,000 times smaller than a strand of human hair, and is named "Nanoscopic phenylalanine Porous Amino Acid Mimic", or Nano-pPAAM,
Their findings, published recently in the scientific journal Small, may hold promise for future design of nanotherapies, said the research team.
Intrinsic anti-cancer therapeutic properties of Nano-pPAAM
As a proof of concept, the scientists tested the efficacy of Nano-pPAAM in the lab and in mice and found that the nanoparticle killed about 80 per cent of breast, skin, and gastric cancer cells, which is comparable to conventional chemotherapeutic drugs like Cisplatin.
Tumour growth in mice with human triple negative breast cancer cells was also significantly reduced compared to control models.
Further investigations showed that the amino acid coating of Nano-pPAAM helped the nanoparticle to enter the cancer cells through the amino acid transporter cell LAT1.
Once inside the cancer cells, Nano-pPAAM stimulates excessive reactive oxygen species (ROS) production – a type of reactive molecule in the body – causing cancer cells to self-destruct while remaining harmless to the healthy cells.
"With current chemotherapy drug treatment, a common issue faced is that recurrent cancer becomes resistant to the drug.
Our strategy does not involve the use of any pharmacological drugs but relies on the nanoparticles' unique properties to release catastrophic level of reactive oxygen species (ROS) to kill cancer cells."
"This novel approach could hold much promise for cancer cells that have failed to respond to conventional treatment like chemotherapy.
Such cancers often have evolved mechanisms of resistance to the drugs currently in use, rendering them ineffective.
However, the cancer cells could potentially still be susceptible to the 'Trojan horse' approach since it acts through a completely different mechanism – one that the cells will not have adapted to."
The scientists are now looking to further refine the design and chemistry of the Nano-pPAAM to make it more precise in targeting specific cancer types and achieve higher therapeutic efficacy.
This includes combining their method with other therapies such as immunotherapy which uses the body's immune system to fight cancer.