From what I understand, they grow cancer cells in corn syrup.
I seriously doubt it. And even if that were the case, the cancer cells in your body NEVER UNDER ANY CIRCUMSTANCES receive RAW corn syrup. If you ingest corn syrup, your liver processes it into other compounds and those byproducts are what has been linked to (which isn't the same as "are proved to cause") cancer.
I grow mushrooms in rye grain. Does that prove rye causes mushrooms?