TA is a Necessary but Not Sufficient Condition for Cancer Proliferation
Over 90% of cancers activate telomerase raising a theoretical concern that TA could be harmful. Dr. Robert Weinberg of MIT points out that in addition to TA, carcinogenesis requires a loss of inhibition (tumor surppressor genes like p53) and a promoter of malignant transformation (a so-called oncogene.)
The Ames Assay shows no carcinogenesis for TA-65
The gold standard for testing whether something causes cancer, the AMES assay showed no effects of TA-65 at levels many times higher than those achievable by the Patton Protocol.
Cancer is Always Caused by DNA Errors
If you have ever made copies from copies, you eventually realize that later editions accumulate rotation, blur, specks and stretching. In the same way, cells inherit whatever errors their ancestors had, with slightly shorter telomeres from replicative senescence.
So you get smart and save your original copy in a safe and separate place, like a clear file folder. That is the role of the stem cells in their respective niches.
Somatic (i.e. run-of-the-mill, non-stem) cells don't tax your resources because eventually, their descendants' telomeres shorten and they'll be forced into apoptosis by p53 and other checkpoint mechanisms. See our Theory of Aging for further details.
Inactivating somatic telomerase is like only giving half a ream of paper to the person who is going to make copies; even in the worst case, they can only make a limited number of bad copies.
The Philadelphia Chromosome
The Philadelphia Chromosome is a well-known DNA tranlocation that causes CML (Chronic Myelogenous Leukemia.) Critically short telomeres on chromosomes 9 and 22 may help facilitate this change.
You Have Already Had Cancer - many times!
Many experts believe cancerous cells are always forming but are recognized and killed by "Natural Killer" cells of your immune system. That is why if TA could improve cellular immune function, it could theoretically suppress cancers.
Thankfully, ordinary cells do not activate telomerase very much. Even if they undergo malignant change, their descendents will die off from the unavoidable truth of the Hayflick Limit, Until they do fizzle out, the Natural Killer cells will keep those non-immortalized (read: non-stem) cells cancer cells from being clinically recognized.
If all our cells were immortal, we would grow into giant blobs because APOPTOSIS (programmed cell death) from natural telomere shortening wouldn't occur. This would lead to very high incidence of lousy "photocopies" throughout our bodies.
Cancer Stem Cells : a New Paradigm
Until recently, science assumed that malignant transformation involved de-differentiation of cells into a more primitive, stem-like state in which the cells The primitive and multipotent features of so-called "cancer stem cells (CSC's)" were attributed to a normal cell's de-evolution into a cell with stem-like traits.
A new theory suggests that ALL cancers begin with errors in a stem cells, which already have the capacity to immortalize using telomerase. The primitive traits would then be inherited rather than reconstituted from an already differentiated somatic (non-stem) cell gone cancerous. This would require less precise and coincidental "hits" from an already DNA-damaged cell.