Eli5: Why brain tumors/cancer exists if brain cells don’t perform mitosis neither regenerate themselves?


As fas as I know, cancer develops after a mistake during mitosis pass unnoticed for both from both the own cell mechanism of regulation and the inmunitary system. But this does not apply to brain cells because they don’t do mitosis yet you can develop cancer in the brain, so how?.

In: Biology

From Mayo clinic

>Secondary (metastatic) brain tumors are tumors that result from cancer that starts elsewhere in your body and then spreads (metastasizes) to your brain.

>Secondary brain tumors most often occur in people who have a history of cancer. But in rare cases, a metastatic brain tumor may be the first sign of cancer that began elsewhere in your body.

>In adults, secondary brain tumors are far more common than are primary brain tumors.

So you’re right, lots of times, brain cells aren’t the issue, and when it is, it’s during childhood, when brain cells are actually being created.

As has been alluded to in the previous answer, brain tumors are most often metastatic from somewhere else in the body. Primary brain tumors are far more prevalent in children because their brains are still developing AND this is where you’re more likely to see bad genetic conditions that predispose people to cancer presenting with primary brain cancer (not always but generally).

The biggest thing with development of cancer is that something happens that damages DNA and your body can’t repair the damage. In cells that rapidly replicate, this is like setting the train of the tracks as with more dividing, the cells gradually accumulate more mutations.

In cells with low to no cell division, you have exceptionally bad luck because the damage to your DNA just so happens to be in a place where it can turn cell division back on

You’re absolutely right: most tumors in the brain don’t arise from neurons, but from various other cell types: meninges (meningioma), support cells (astrocytoma/glioma, oligodendroglioma, schwannoma), tumors arising from embryonal cell populations (medulloblastoma), from the cells lining the brain’s ventricles (ependymoma), cell arising from embryonic cartilage cell remnants (chordoma, chondroma, chondrosarcoma).