[oooyay]

idk why I see so many comments like this on the medical threads of HN lately. Laboratory mice are close enough to us to do testing on and have provided reliable results throughout their use. A basic Wikipedia search shows references for all of those claims and more: https://en.wikipedia.org/wiki/Laboratory_mouse

[cyberax]

That's because mouse models suck for many diseases. Cancer very much included, for two reasons:

1. Mice _love_ to get cancer naturally. If you have 100 mice, it's quite likely that around 20 of them will die within one year of cancer. This makes it difficult to extract useful signals. BTW, that's why if you see a study that a "chemical X results in cancer in mice", you should take that with a grain of salt.

2. Mice are small, so tumors are necessarily small too, with several orders of magnitude fewer cells than typical human tumors. So many drugs can just cure mice of cancer entirely, by killing cancerous cells too quickly to allow them to evolve resistance.

[maratc]

> If you have 100 mice, it's quite likely that around 20 of them will die within one year of cancer.

If you have 100 people, about 40 of them will be diagnosed with cancer over their lifetime (39/100 females and 41/100 males). Note "diagnosed with" is very different from "die" and "over lifetime" is not the same as "within one year", but the probability of people getting cancer naturally is high as well.

[cyberax]

Sure. But in general, cancer risk should scale with the number of cell divisions, which is fairly low for mice. And other small, short-lived mammals like weasels are not as susceptible to cancer. Naked mole rats (also rodents!) are downright cancer-proof.

This all means that mice don't have a good natural cancer-suppression machinery, and this in turn makes them somewhat awkward to use to discover new treatments.

[glenstein]

I'm not sure it follows that high incidences of cancer means that it's unhelpful to use them for research to understand the mechanisms of cancer. And I'm not sure that either of your observations one or two are pertinent in this case as it applies to the on/off protein switch, as it is not about guaging the statistical frequency of cancers or about killing cancer cells.

[cyberax]

Murine models are not unhelpful, just very tricky. Quite a few experimental data turned out to be incorrect because experiments were poorly conducted.

[mbreese]

It’s a common trope in the field that we’ve already cured cancer in mice. They are similar enough to be a useful model for study. However, they are still quite different to the point where you never quite know how treatments will react… especially in cancer.

The biggest issue is that the mice we use for research typically have no or a highly depleted immune system. One of the biggest breakthroughs in the cancer field (IMO) is the development of humanized mice. These are mice that have had their immune system genes replaced with the human versions of these genes.

This is incredibly important for work like this where you’re studying cancer cell-immune cell interactions.

[glenstein]

Have we actually cured cancer in mice?

[lossolo]

What I'm really curious about is how many of these experiments and trials didn't work in mice but would work in humans.

[panabee]

it's plausible that some would: chocolate and coffee are toxic in mice but not humans.

unfortunately, we need mice models for safety for now.

hopefully, computational models and personalized medicine will change this in the future.

[wombatpm]

One would hope that in vitro studies with human cell lines would identify those possibilities.