One of the latest methods pioneered by scientists to treat cancer uses a Trojan horse to induce cancer cells to self-destruct, all without the use of drugs.
The key to the technique is the use of a nanoparticle coated in a specific amino acid called L-phenylalanine, one of many such acids that cancer cells rely on to grow. L-phenylalanine is not produced by the body, but is absorbed by meat and dairy products.
In tests on mice, the nanoparticle – called Nano-pPAAM or Nanoscopic Phenylalanine Porous Amino Acid Mimic – killed cancer cells specifically and effectively, presenting itself as a friendly amino acid before causing cell destruction.
The self-destruct mode is activated when the nanoparticle overdrives the production of certain chemicals known as reactive oxygen species (ROS). It is enough to break down cancer cells while leaving nearby healthy cells intact.
“Against conventional wisdom, our approach instead involved using the nanomaterial as a drug [of] as a drug carrier, “says materials scientist Dalton Tay of Nanyang Technological University in Singapore.
“Here, the carcinogenic and lethal properties of Nano-pPAAM are inherent and do not need to be activated by external stimuli. The amino acid L-phenylalanine acts as a Trojan horse, a cloak to mask the nanotherapy inside.”
Nano-pPAAM has been shown to kill about 80% of breast, skin and stomach cancer cells in mice, almost on par with current chemotherapy drugs (but without all the side effects, of course). Although dangerous to cancer cells, it is based on a silica nanoparticle classified as safe for humans by US food regulators.
The approach is expected to simplify the production of this type of treatment, although there is still a long way to go before these laboratory tests lead to effective treatments for people. Only lab and mouse tests have been done so far, but the first results are promising – just one of the many ways scientists are trying to rid the body of cancer.
Many recent studies have looked at ways that nanoparticles can better target cancer cells without disrupting the rest of the body too much, but they are usually loaded with drugs, which is not the case here.
This will help in recurring cancers that eventually become resistant to the drugs we bomb them with – there are no drugs involved here, so there is nothing to become resistant to.
“This new approach could hold great promise for cancer cells that have not responded to conventional treatment such as chemotherapy,” says breast cancer specialist Tan Ern Yu of Tan Tock Seng Hospital in Singapore, who was not involved in the study.
The research was published in Small.