Discoveries of potentially life-saving peptides in the venom of deadly animals are, counter-intuitively, not all that rare. Scorpions, rattlesnakes and funnel-web spiders have all provided scientists with promising building blocks for next-generation medicines, and a dangerous Australian arachnid has again reared its head with a compound in its venom found to be a potent killer of melanoma cells.
The research was carried out by scientists at Australian research institute QIMR Berghofer and the University of Queensland, who were inspired by a peptide found in the Brazilian spider Acanthoscurria gomesiana. This peptide, called Gomesin, is known to have cancer-fighting properties, and because the Australian funnel-web spider's venom carries a peptide of a similar chemical nature, the team thought it worthwhile to see how it stacked up.
"In our laboratory experiments we found that the Australian funnel-web spider peptide was better at killing melanoma cancer cells and stopping them from spreading than the Brazilian spider peptide," explains Dr Maria Ikonomopoulou, who led the study. "Additionally, the Australian spider peptide did not have a toxic effect on healthy skin cells. When we tested the Australian spider peptide on human melanoma cells in the laboratory, it killed the majority of them. We also found the peptide slowed the growth of melanomas in mice."
Interestingly, the peptide was found to have positive effects for another creature native to Australia, the Tasmanian devil. These meat-eating marsupials often succumb to what is known as Tasmanian devil facial tumour disease (DFTD), a transmissible cancer spread through biting that often leads to their death. So much so, the species is now listed as endangered.
The scientists extracted cells from facial tumors of affected Tasmanian devils and tested how effectively the compound was able to kill them off. Like the melanoma cells, the compound was found to destroy them rather swiftly, so the team began experimenting with its chemical makeup to see if variations could prove even more potent.
"When we altered two particular amino acids in the peptide chain, the compound became even better at destroying the DFTD cells," says Ikonomopoulou. "This research is still at a very early stage, but these results are very promising. There are many years of work ahead, but we hope that this compound could in the future be developed into a new treatment for melanoma and DFTD."
Beyond that, the team says the discovery provides fresh impetus to continue exploring how bioactive compounds in venom can be used to treat not just cancer, but liver disease, obesity and disorders relating to metabolism.
The research was published through a series of papers in the journals Scientific Reports and Cell Death.
Source: QIMR Berghofer
