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Originally Posted by PamWinterReturns
That’s recurring cancer. What causes a cell to turn cancerous? If radiation, chemotherapy and cell removal doesn’t eradicate it, they need to find out why a cell develops abnormally. Only then can you create a cure.
They have proof carcinogens cause cancer. Not everyone is affected, though, so why some and not all? It isn’t inherited yet runs in families. Why do more women than men get breast cancer? More cells?
Animals get cancer. Dogs don’t eat soy, smoke, eat burned food, sniff carcinogenic materials or eat much sodium, yet get cancer. What’s the common denominator in people and pets?
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OK, the first thing you need to realize is that we all have the genes for cancer. These are called oncogenes. For most of us our oncogenes are missing the required start codons, a specific three base pair upstream of the genes that tells translation proteins where to start reading the code to build the proteins encoded. For eukaryotes - people and animals - the start codon is 'AUG'.
The second important thing to know is that point mutations - single base pair changes in our DNA - happen fairly regularly. Some think it's the accumulation of these small changes over time that we perceive as aging. Also, our DNA is incredibly long and most of it is junk - meaning it doesn't code for anything. For the most part, if these random changes happen in that junk area then there is no effect. If it happens in the gene code, then a single amino acid in the protein being encoded is changed. So if you have blue eyes, a single cell might be changed to now code for brown pigmentation, and the change will largely be masked by the rest. But, if it happens upstream of the oncogenes, it can turn that junk region into a start codon.
Now, when we talk about carcinogens, we are talking about substances that interfere with how our DNA is copied. Basically, carcinogens increase the likelihood that point mutations will occur. Again, most of our DNA is junk, so a single change isn't likely to be a big deal. But, we're talking about this occurring in every cell of your body, over and over again for your entire life. The more frequently a cell divides the more it's genetic code is copied, which means more opportunities for errors to occur.
So, lets say a particular oncogene you got from your dad (you have 2 versions for every gene - one from your mom, and one from your dad) has the start codon at AUC. It is just one base code away from being the AUG required for that oncogene to be expressed. And, it's found in every cell of your body. All it takes is for a random point mutation to happen in just one of the billions of cells making up your body at just the right spot to result in that cancer being turned on. Toss in some smoking or other risk factors, and the odds go up.