extended lifespans<\/a>, underscoring the importance of genome maintenance for longevity.\u201d<\/p>\nThe \u201cmulti-stage model of cancer\u201d is a widely accepted framework that explains how normal cells don\u2019t just turn into cancer cells in one step, Gorbunova says. Instead, cancer develops after multiple genetic mutations or \u201chits\u201d\u2014called oncogenic hits\u2014accumulate in key genes that control cell growth, division, and DNA repair.<\/p>\n
Most human cancers arise after a cell accumulates five to seven \u201chits.\u201d A person\u2019s inherited genes, the type of tissue involved, and environmental exposures can all influence how many hits it takes for cancer to emerge.<\/p>\n
Given this multi-step model, one might expect that animals with more cells and longer lifespans would accumulate more hits and therefore face higher cancer risks. But that is not what scientists observe. This puzzle is known as Peto\u2019s Paradox. Large species don\u2019t have higher rates of cancer compared to smaller animals, even though they have far more cells dividing over many more years. The paradox suggests that larger species such as elephants and whales must have evolved additional mechanisms to prevent or repair cancerous mutations. Exactly what those mechanisms are has long vexed scientists.<\/p>\n
\u201cWe first hypothesized that oncogenic hits might explain this, and a whale would need six or seven hits to make them more cancer-proof,\u201d Gorbunova says. But when the researchers tested how many mutations it takes for bowhead whale cells to turn cancerous, they discovered that bowhead whales actually need fewer hits than humans.<\/p>\n
Instead, Gorbunova continues, \u201cwe found that whale cells are less likely to accumulate oncogenic hits in the first place.\u201d<\/p>\n
By combining genomic data with molecular biology experiments, the researchers studied cells harvested from bowhead whale tissue and analyzed proteins involved in DNA repair, shedding light on the cellular mechanisms that help whales live exceptionally long, healthy lives. While several DNA repair proteins were more abundant in bowhead whales than in other mammalian species, one protein was particularly remarkable: CIRBP.<\/p>\n
\u201cThere were some other proteins that were expressed in bowhead whales at slightly higher levels, but CIRBP stood out because it was present at 100-fold higher levels,\u201d Gorbunova says.<\/p>\n
To further test CIRBP\u2019s abilities, the team added bowhead whale CIRBP to human cell cultures and fruit fly cells. In both cases, DNA repair improved, and, in fruit flies, it even extended their lifespan.<\/p>\n
Collaborating with scientists in Alaska who are investigating how animals adapt to cold, the researchers discovered another intriguing aspect of CIRBP.<\/p>\n
\u201cIf we just lower the temperature a few degrees, cells make more CIRBP protein,\u201d Seluanov says. \u201cWhat we don\u2019t yet know is what level of cold exposure would be needed to trigger that response in humans.\u201d<\/p>\n
Gorbunova says the team is considering multiple ways to ramp up the protein in humans. And some approaches may involve people\u2019s everyday habits.<\/p>\n
\u201cBoth boosting the body\u2019s existing CIRBP activity or introducing more of the protein may work,\u201d Gorbunova says. \u201cLifestyle changes\u2014things like taking cold showers\u2014might contribute too and might be worth exploring.\u201d<\/p>\n
For now, these ideas are hypothetical, and the researchers caution that it\u2019s too early to know whether they would work in people.<\/p>\n
The next step, Gorbunova says, is further testing CIRBP to better understand whether this bowhead whale-inspired defense could someday help humans resist cancer and other age-related diseases.<\/p>\n
\u201cThere are different ways to improve genome maintenance and here we learn there is one unique way that evolved in bowhead whales where they dramatically increase the levels of this protein,\u201d Gorbunova says.<\/p>\n
\u201cNow we have to see if we can develop strategies to upregulate the same pathway in humans.\u201d<\/p>\n
Source: University of Rochester<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"Share this Article You are free to share this article under the Attribution 4.0 International license. Bowhead whales\u2019…\n","protected":false},"author":2,"featured_media":119867,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[2992,61,60,71637,82,4380],"class_list":{"0":"post-119866","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-science","8":"tag-aging","9":"tag-ie","10":"tag-ireland","11":"tag-lifespan","12":"tag-science","13":"tag-whales"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/posts\/119866","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/comments?post=119866"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/posts\/119866\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/media\/119867"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/media?parent=119866"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/categories?post=119866"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/tags?post=119866"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}