sharks don’t get cancer?

It turns out that if you thought that foetal lamb cells as a treatment for autism (& a range of other disorders & illnesses) was the pinnacle (or should that be ‘the depths’?) of silliness, you’d be wrong. Dr Huertgen has competition.

It was previously believed that sheep were the best donor animals because of their five or six embryos.

Yes, let’s just consider that for a moment. A ‘therapy’ based on tissue from near-term foetal lambs will of necessity require the death of those lambs, & probably also the mother. I wonder if the idea went anywhere near an animal ethics committee?

However, with the results of recent research, shark embryo cells seem to be vastly superior to sheep embryo cells, in particular the blue shark (Cacharius glaucus) found only in the waters of the Pacific Ocean. (It is important to note that sharks are hunted and killed daily, and the embryonic sac is normally thrown away as worthless.)

Using an otherwise wasted byproduct – that sounds really good, doesn’t it? No, it doesn’t. Finding another use for bits of sharks that might otherwise be thrown away, seems to be simply adding to the pressure on these top predators. And the ongoing decline in shark population numbers can have much broader ecological implications.

The shark has a perfect immune system in that it is free from cancer and has no contagious diseases. 

While Orac’s already discussed this** at some length, I thought I’d look again at this idea as it’s one that I hear relatively often from students. The idea that sharks don’t get cancer seems to be an enormously popular myth, but that’s all it is, a myth. Until recently there was little research on tumour development in sharks, but where that work’s been done, tumours have been found. Unfortunately it’s a myth that’s probably only increased the over-fishing of sharks, as various preparations of shark cartilage are on offer to help people fight off cancer.

As for the bit about "no contagious diseases" – again, completely untrue. Sharks are subject to a range of bacterial & viral infections, plus parasites, & in fact exposure to those disease agents has played a large role in the evolution of the vertebrate immune system.

It has so far proven impossible to produce cancer cells in the blue shark and this animal also will never accept the HIV virus, for example.

SInce HIV is a virus that infects primates, this is hardly surprising, nor is it a rationale to use shark tissues to attempt a ‘cure’.

Additionally the blue (and other) sharks have circulating antibodies as immunoglobulin already circulating in their blood. Equally important, the cells used in Live Cell Therapy should be from a specie which has a comparable pregnancy time to the human, such as the blue shark.

Methinks someone doesn’t really have a good handle on the immune system. Immunoglobulins – we have them too!

And why, oh why, should the animal’s gestation period have anything to do with it?

Oh wait, it sounds sort of science-y, right? And of course, it makes this ‘treatment’ sound so much better than, say, that ovine example we looked at. That is, If it’s possible for one pile of of bovine excrement to look, sound or smell better than another…


** I really don’t know how he can bear to read so much of this material, although I suppose being a small plexiglas box full of blinking lights*** probably helps.

*** Oracian in-joke.

8 thoughts on “sharks don’t get cancer?”

  • Jim Thomerson says:

    Specie is not the singular of species. My dictionary defines specie as a coin, The singular of species is species. I’m not inclined to take seriously the thoughts of someone who does not do that, but, probably that is just me.

  • Alison Campbell says:

    I noted that as a flag that they probably had no idea what they were talking about, but the other bits were far more ‘attractive’ to focus on.

  • herr doktor bimler says:

    Sharks are subject to a range of bacterial & viral infections, plus parasites
    I looked up the Blue shark in Whackyweedia (just to confirm my suspicion that its Linnean name is not Cacharius glaucus), and found this:

    The captivity record for blue sharks as of 2008 was held by The New Jersey Aquarium for a specimen that lasted roughly 7 months before expiring of an apparent bacterial infection.

    OTOH, the similar “gestation” period means that if Blue sharks *do* get cancer, they can be cured with an injection of ground-up human fetal cells…

  • herr doktor bimler says:

    Your concern for endangered shark populations does you credit… but let’s be honest, for ‘Dr’ Velazquez to include genuine shark-sourced material in his products, he would have to (a) believe his own bullshit, and (b) care about the welfare of his patients. Does he really come across as either?

  • Alison Campbell says:

    Frankly, no. One could use a number of adjectives here, but those you chose weren’t on my list. OTOH anything that increases demand on the poor old shark populations is a Bad Thing, & the gullible or desperate are likely to read ‘Dr’ V’s nonsense & then clamour for shark products, so…
    (I hope that makes sense, I have spent a very long – albeit interesting – day in interviews & my brain is starting to slow down!)

  • Alison Campbell says:

    Not exactly – it “presents a framework for evaluating effects of CAM”. The article you’ve linked to does not look at the actual evidence – & in fact comments that to date any evidence offered for effectiveness of CAM is at best inconclusive.

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