Panic over immortal sea creature that can create a form of cancer that’s contagious

A jellyfish-like creature with tentacles and seeming ability to live forever has now been found capable of passing cancerous tumors on to its offspring.

Government scientists in France who studied these ‘brown hydra’, so-named after the lake monsters of Greek myth, voiced concern that their ‘transmissible cancers’ could bode ‘dramatic ecological consequences’ if allowed to spread in the wild.

While brown hydra have only been seen to develop these tumors in the lab, the phenomenon nearly drove Tasmanian devils to extinction off the coast of Australia in the past decade.

And researchers now worry that pollution could produce more contagious cancers – but said it remains unclear if similar forms of the disease could afflict humans.

Above, a tumor-free example of the brown hydra from the researchers’ laboratory population, grown via samples obtained from Montaud lake in the south of France

‘Human activities may unknowingly create conditions that favor the spread of these cancers,’ according to the study’s lead author, evolutionary ecologist Sophie Tissot.

Prior to the new research, published Tuesday in the Proceedings of the Royal Society B, both cancer researchers and wildlife biologists had assumed that these contagious cancers could only spring into existence via a rare ‘perfect storm’ of host and cancer cell attributes.

But the new findings by France’s national research agency, le Centre national de la recherche scientifique (CNRS), have showed that the transmissible cancers could emerge simply from overfeeding. 

Tissot and her colleagues fed their lab colonies of brown hydra (Hydra oligactis) larval shrimp (Artemia salina) for both their control and experimental groups. 

The choice was suggestive of the kind of human activities, like aquaculture farming, that can lead to overfed blooms of gorging, tiny, brown hydra out in the real world. 

Hydra ‘can occasionally grow to large numbers,’ according to a field guide notice by the Missouri Department of Conservation.

‘And when this happens in fish hatcheries,’ the US state agency warned, ‘they can be a serious threat to newly hatched fry [baby fish or shrimp].’ 

Prior to this study, brown hydra had gained the attention of biologists who study freshwater ecosystems for the creature’s seemingly infinite longevity.

Brown hydra not only defy aging but can also regenerate damaged tentacles.

Fortunately, Tissot and her team also found that these transmissible cancers were often ‘fragile’ and could go into remission if they fed their brown hydra less. 

Her CNRS group and other investigators of transmissible cancers now hope to use the fast lifecycle of hydra to better understand transmissible cancers in the lab. 

‘It’s certainly a more tractable system than keeping 1000 Tasmanian devils in the lab and watching them to see if they develop cancer,’ as biologist Michael Metzger told the news arm of the journal Science. 

Above, an image of one of the study’s brown hydras that developed the transmissible tumors – visible as lumps along what would typically be its long thin body.  The team behind the new researchers took these images with a camera-mounted or trinocular microscope 

‘Human activities may unknowingly create conditions that favor the spread of these cancers,’ according to the study’s lead author, evolutionary ecologist Sophie Tissot. According to the Missouri Department of Conservation, blooms of these hydra can infest shrimp and fish farms

Metzger who studies cancer evolution at the Pacific Northwest Research Institute in Seattle, Washington, described brown hydra’s potential for revolutionizing cancer research as ‘really interesting.’

‘You can really learn a lot [from them] about fundamental aspects of cancer biology,’ according to Metzger, who was not affiliated with the new study.

Tissot and her colleagues CNRS were able to induce cancer in their experimental groups of brown hydra in less than two months, and tracked between four-to-five generations of the tiny carnivore to observe the contagious tumors passed down.

Thanks to their control groups and knowledge of the hydra’s genetic predispositions for cancer, the team concluded that a ‘contagious’ tumor was the most likely explanation for successive generations of creatures acquiring their parent’s tumors.

‘If this conclusion is confirmed in the future,’ Tissot and her team wrote, ‘it is crucial to consider these aspects in the study of ecosystems disturbed by human activities.’

Human activities, not unlike a shrimp or a fish farm infested with a feed-frenzy of brown hydra, the noted ‘could potentially modify the conditions that favor the spread of transmissible cancers.’

Metzger noted that it’s too early to see what discoveries related to the brown hydra’s transmissible cancers might mean for the form of the disease in humans.

‘They’re a little bit different from what happens in humans,’ he cautioned, ‘but I think that is their value. It shows the breadth of what cancer can look like.’