Cool Video: Repurposing Genes, Repurposing Drugs Although they are single-celled fungi, yeast like this Saccharomyces cerevisiae specimen (Image: Saccharomyces cerevisiae)
have genes in common with other, more complex organisms, including humans, by virtue of their shared evolutionary history. For example, yeast have a gene, rab11b, that becomes active when they experience environmental stressors like heat. That gene in yeast, which have no blood… (Images: Frog embryo with normal rab11b activity, Frog embryo with disrupted Rab11b activity)
…has been repurposed to regulate vein and artery growth in vertebrates like frogs, mice and humans. (Images: Tadpole with normal blood vessels (top), tapole with reduced blood vessel growth (bottom))
Scientists studied that gene to find a drug that could keep new blood vessels from forming. (Image: Fibrosarcoma Tumor)
Stopping this formation could aid cancer treatments because tumors recruit new blood vessels to feed their growth. In searching for a molecule that would block the yeast genes, the researchers found an unlikely candidate– thiabendazole, an anti-parasitic agent with anti-fungal activity. Following up with more studies, the researchers showed that the compound reduced the growth of blood vessels in frog embryos and inhibited the growth of human blood vessel cells. Thiabendazole also decreased the emergence of new blood vessels (Images: Untreated and treated mouse tumors)
and reduced the size of tumors in mice with cancer. In addition to their potential cancer treatment applications, the findings more generally demonstrate the value of an evolutionary approach to drug development. Hye Ji Cha, Edward Marcotte & John Wallingford, University of Texas at Austin. Research supported in part by the National Institute of General Medical Sciences Images and video courtesy of Hye Ji Cha, PLoS Biology, drugs.com and public domain National Institute of General Medical Sciences, National Institutes of Health, September 2012.