Cancer, antioxidants, cells, active oxygen, etc.

I've been thinking that concept about oxidants and cancer are wrong. Of course they can damage healthy cells but that is most important they are damaging cancer cells as well and in greater degree. See my article about cancer and active oxygen species http://www.cancermonthly.com/iNP/view.asp?ID=232 also enzyme catalase which decreasing by age is responsible for grey hair and this enzyme also is producing reactive oxygen species so not only grey hair increasing but cancer as well by age can be due to it's decreasing by age. Hence we can use catalase not only to restore grey hair but to prevent cancer.