woah! i didn’t even know something like this was possible. frightening. i don’t even understand how tapeworm cancer cells could leave the tapeworm and travel and implant like they did, I’m guessing that the fact that the persons immune system was severely compromised due to HIV played a large part in making this possible.
Sure. But there’s also the fact that parasites that have evolved to infect humans are also pretty good at not irritating the immune system, and trying to be relatively bio-compatible with the host. I mean, the ones that were bad at living in a human aren’t around anymore. Natural selection being what it is.
What the actual fuck?!
That’s bad luck!
I looked into some wikipedia and focusing on https://en.wikipedia.org/wiki/Taenia_saginata which is transmitted between cattle and people the tapeworm has 2 forms, one which attacks cows differently than people. Apparently in cattle rather than forming a tapeworm the larvae will tunnel into the cows muscles from their blood stream after penetrating their intestinal membrane (then create a sort of cocoon sheltering themselves), in people it forms into a worm that hatches the same larvae, but we pass (ahem) them without it hooking to into us (some physiological difference i assume).
My guess is if the tapeworms cancer was in its reproductive system (probably half the worm really) may have caused the larval bits it regularly sheds to attach into the person like it would with the cow and such larva could survive in our tissues as they do with cattle but continued to grow beyond their typical size (since they were cancerous).
There’s probably more to it. Cancer is still mysterious in people let alone other classes of organisms.
Makes me wonder what gives a tapeworm cancer.
Anybody else really want to hear what Werner Herzog has to say about this?
As the authors note
" Multicellular parasites that live
in host tissue generally possess cellular mechanisms
for host tissue invasion and immune
evasion; these mechanisms could potentially be
co-opted during malignant transformation
within the host"
This guy didn’t provide us with much information(we know that the tapeworm involved is quite successful in the gut; and can invade other tissues; but that’s in its normal larval or adult form, not this novel cancer form) since he was badly immunocompromised (HIV patient not adhering to antiretroviral therapy) and any number of normally-hapless organisms could likely have succeeded in colonizing him(according to the paper; when they first concluded that the cells weren’t human, they suspected amoebas or slime molds, since the cells were clearly eukaryotic; but lacked the structural differentiation expected of multicellular parasites.)
Given how vulnerable the immunocompromised are to all sorts of infections that are highly unusual in patients with normal immune function, we don’t really know much about how successfully free-living tapeworm cells could be in humans. Hopefully not very.
(edit: link to paper; fairly short and not brutally technical)
It’s too rare to know yet; but the authors speculate that compromised immune function(in addition to making the uncontrolled proliferation easier) may have helped induce the abnormalities in the tapeworm. Being filthy parasites, they’ve evolved in an environment where host immune response is a normal, expected, more or less constant, environmental condition. A host with such a weak response would be a markedly abnormal environment, potentially one they aren’t well adapted to develop normally in.
On the bright side the tapeworm was an inspiration to many as it dealt with its cancer with humor and courage.
So gross! I feel really bad for this guy.
Oh great. One more thing to lay awake worrying about. What if there’s an epidemic of cancerous tapeworms?
What is it with tapeworms today?
Wow, today’s news – tape worms in the brain, tape worms transmitting cancer…
I don’t like the direction this is heading. I have my hands full just keeping my eyes on the cockroaches.
Yes, I heard about both today too. Makes me wonder if tapeworm-killing chewies are available, like those things for heartworm that are made for dogs.
Gah, how to avoid this??? So far I’m hearing don’t eat pork, and don’t walk around without shoes on. Wait, that’s hookworm, right? scurries off to scour the interwebs
All I know is, at this point, the presidential candidate promising a war on tapeworms gets my vote.
I had hookworm a few times as a child. Its not that bad. The treatment was a powder you dissolved in juice and drank twice a day every day for a week or more. The side affect of the treatment however is pooping out a bunch of living worms. As the treatment only dissolved the hooks, and doesn’t harm the worms. But as its highly infections all family members and pets also need to be treated at the same time. So everyone would be very annoyed with me for the duration of the treatment.
No joke–I envy your experience. I had ringworm on the back of my neck when I was a kid. The only treatment was enormous penicillin tablets that got stuck in the back of my throat and tasted awful. My doctor told me, “When I was a little boy they’d shave your head and paint it purple.” I said “Cool! Can we do that instead of the pills?”
This was not the reaction he was expecting.
Tapeworms will travel into various human tissues and form those cysts as well, including the brain. (Do NOT Google image search “tapeworm brain.” Really. /Shudder.)