“Roses are red, it’s hot as hell: the mitochondrion activates the nuclear self-destruct sequence of the cell.”
Embarrassingly for science educators across the country, it has become a well-known sort of in-joke among non-STEM people who had to suffer through biology class that, “well, I don’t remember much in biology class that actually helped me with life, but I do remember that the mitochondria [sic] is the powerhouse of the cell.”
But how many people know that the mitochondria activate the nuclear self-destruct sequence of the cell? My use of “nuclear,” is literal: this self-destruct sequence goes on to destroy the nucleus. One of the key hallmarks of cancer is that cancer cells generally try to turn their mitochondria off so as to not to trigger this self-destruct sequence many biologists know as apoptosis.
Cancer cells “try” to turn off their mitochondria as they grow uncontrollably because cancer cells, too, undergo natural selection and evolution, or what the public popularly construes as “survival of the fittest.” The descendants of the first cancer cells that turns off their mitochondria activates the cellular self-destruct sequence much less often than those who let their mitochondria stay on.
How does the mitochondria trigger this self-destruct sequence? This self-destruct sequence occurs when extensive damage, from cancer, viruses, chemicals or otherwise, causes the release of a particular mitochondrial energy carrier called cytochrome c. The presence of this particular energy carrier protein — which is supposed to stay firmly within the mitochondria — observed outside the mitochondria is a clear panic signal to the remaining “guardian” proteins who haven’t been totally subverted or inactivated by the cancer that the damaged cell is indeed, now a threat to the rest of the body. For the sake of the greater genomic good, the cell must now be terminated. This triggers the self-destruct sequence.
An interesting clinical observation is that cancer cells are often easily destroyed by reactivation of oxygen-using cellular respiration enzymes in the mitochondria, to the point that these enzymes — such as the pyruvate dehydrogenase complex — have now become a serious anti-cancer target.
Will one day “the mitochondrion triggers the self-destruct sequence of the cell” be just as memorable as the powerhouse concept? Perhaps, a mantra as well-known by patients at the doctor’s office? One day it might be a mantra that might save lives. Almost everyone has loved ones or friends with cancer, and knowing anything about apoptosis would help patients make better, more-informed decisions about their treatment.
The idea that the mitochondria is the powerhouse of the cell is a memorable concept that sticks in the mind of the general public. However, if the general public doesn’t learn much else, this little factoid is pretty much a useless concept. In an era where snake oil peddlers sell homeopathic remedies for cancer, how can we make the public understanding of apoptosis more accessible in the same way, with the aim of perhaps saving lives?