Capsaicin (8-methyl-N-vanillyl-6-nonenamide) is the "heat" of hot peppers. Researchers from the Ruhr-Universitat Bochum found that capsaicin and helional (the scent of fresh sea breeze) activated Transient Receptor Potential Channels (TRPV1s-an olfactory receptor typically found in the fifth cranial nerve) in cultivated triple-negative breast cancer cells. Exposed cancer cells divided more slowly and died in large numbers. There are still many studies that suggest that hot peppers could cause cancer but these are usually gastrointestinal cancers.
Since these are cultured cells, it's really unclear how many hot peppers one would need to consume to achieve the concentration of the cultured cells. I have tried the cayenne supplements (500 mg) and find them to be a little harsh, even on a full stomach. But, if you enjoy spicy food, sprinkle some on!