Life is precious, and the way a life starts and forms inside another life takes my breath away. I’m talking about pregnancy or reproduction.
The fetus wouldn’t survive without its placenta, which interfaces with the inner lining of mom’s uterus. It’s an overlooked miracle, that the fetal tissue (the placenta) INVADES and grows INTO the mom’s uterine wall. Think about it. The fetus and the mom are two genetically distinct individuals. For this reason, I would not be able to donate one of my organs to my mom without first having to shut her immune system down. Her immune system would see any organ I donate as foreign.
So does the mom’s uterus make an exception for the baby’s placenta just because the baby’s cute? Not quite, I mean the baby’s cute, but that doesn’t explain things. As it turns out, the fetus’ placenta has an enzyme that breaks down tryptophan (one of the amino acids that our body cannot make and must obtain from our diet), and tryptophan is needed by fighting immune cells. This depletion right at the fetal-maternal interface has been shown to suppress the mom’s immune cells and prevent them from attacking the fetus’ placenta. What amazing precision!
And what does this have to do with cancer? Cancer cells have been shown to posess extra high levels of the enzyme that breaks down tryptophan. At least one biopharmaceutical company has been trying to get FDA-approval for an anti-cancer drug that aims to inhibit this enzyme, which is one of the ways cancer cells suppress the local immune cells – copycats!