> Adrienne Smith wrote:
>
> Cetuximab -- one of the drugs Cordain mentions is another name for
> Erbitux. Now maybe the drugs have been improved -- but below
> is a link to
> a 2002 Townsend Letter article which details the early disappointing
> failure of EGF blocking drugs in actual patients. I think
> this EGF thing
> may be a big red herring that will translate into big bucks
> for big pharma -
> - sounds great on paper and works in a petri dish -- but
> fails with respect
> to actual tumors in actual patients... Thoughts? One particularly
> interesting quote:
>
> "So, while on Saturday oncologists were applauding Dr.
> Mendelsohn for his
> brilliant insights, on Monday they were hearing that a
> treatment based on
> these insights simply did not work. If it were true that EGF "plays a
> critical role in the process that regulates tumor cell growth and
> survival," as ImClone still claims on its website, then one
> would expect a
> treatment that targets EGF to yield significant clinical results. It
> doesn't."
>
>
>
http://findarticles.com/p/articles/mi_m0ISW/is_2002_August-Sept/ai_90794440
[Ralph W. Moss, Townsend Letter for Doctors and Patients, August-Sept,
2002]
The point that the clinical results of cetuximab (brand name Erbitux) have
not been promising is a good one, Adrienne. However, Cordain actually isn't
taking the position that the drugs work. Rather, he is arguing that avoiding
cancer in the first place by not drinking milk (and other Neolithic foods)
might be a better strategy. Also, while the results of cetuximab may not
have been great, not all the tyrosine kinase inhibitors (selective
inhibitors of epidermal growth factor receptor's tyrosine kinase domain)
have had such poor results. Imatinib (Gleevec) has had good clinical results
and even the source you quoted--medical writer Ralph W. Moss--wrote that
"Gleevec in particular is a very worthwhile agent" (Reflections on ASCO
2005, Townsend Letter for Doctors and Patients, August-Sept, 2005,
http://64.241.242.253/p/articles/mi_m0ISW/is_265-266/ai_n15341114). Indeed,
in the very article you cited, Moss stated: "Gleevec resulted in
significantly greater reductions in the number of cancer cells in the bone
marrow, which led to the complete disappearance of cancer cells in 40% of
the patients." The clinical results of Gleevec after five years look very
positive indeed: "The longest follow-up yet of chronic myeloid leukemia
(CML) patients treated with Gleevec shows a survival rate of 95% after five
years." ("5 Years Later, Gleevec Fights Cancer,"
www.webmd.com/content/article/130/117735?src=RSS_PUBLIC)
Also, curcumin is a tyrosine kinase inhibitor that has had good laboratory
results and is the active ingredient of a spice (turmeric) rather than a
synthetic pharmaceutical (Hong RL, Spohn WH, Hung MC. Curcumin inhibits
tyrosine kinase activity of p185neu and also depletes p185neu. Clin Cancer
Res 1999; 7: 1884-1891.
http://clincancerres.aacrjournals.org/cgi/content/abstract/5/7/1884). So
curcumin has generated positive laboratory results as a tyrosine kinase EGF
inhibitor despite not offering potential big profits for pharmaceutical
companies.
While research into the chain of causation between betacellulin, growth
factor receptors and cancer is not conclusive, it is suggestive and I think
it's too early to conclude that it's a red herring. As Cordain states, while
"observational epidemiological studies cannot show cause and effect between
diet and disease, they suggest that milk drinking and dairy consumption is
linked to a variety of cancers...."
------
P.S. I missed the following direct answer in Cordain's article to the
earlier question of whether bovine betacellulin is broken down by enzymes in
the human digestive system:
"You might think that protein shearing enzymes in your gut would breakdown
betacellulin and other hormones belonging to the EGF hormonal family before
they can get to the gut EGF receptor. However, this is not the case, as
cow's milk contains peptidase inhibitors which allow EGF to remain intact
even in human digestive juices of the stomach and small intestine (11)."
11. Rao RK, Baker RD, Baker SS. Bovine milk inhibits proteolytic
degradation of epidermal growth factor in human gastric and duodenal lumen.
Peptides. 1998; 19(3):495-504.
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