Methionine Dependence of Some Types of Cancer Cells

[Guest guest]

Hi folks:

A little more on methionine (MET). Here are six papers which

indicate that certain very common types of cancer are dependent on

MET for their survival/proliferation. Two of the papers are quite

old (1993). But the other four are from 1999, 2001, 2002 and 2003:

Here are some excerpts from one of them:

" Discussion.

The results in this report demonstrate that ........... methionine

dependence occurs in a sizeable proportion of fresh human tumors.

Thus 5 of 21 human tumors analyzed ........ were determined to be

methionine dependent " .

(Those were cancers of the breast, colon, melanoma, ovary and

prostate. Three of these are very common cancers.)

Further: " In this light, recent in vivo studies of the effects of

methionine depletion by both dietary and enzymatic means have

indicated anti-tumor efficacy. Methionine depletion has also led to

tumor cell cycle arrest in vivo " .

" In summary, the results presented in this report indicate that fresh

human solid tumors frequently express methionine dependence and

suggest that methionine is a potential target for cancer

chemotherapy " .

PMID: 8495409

Other papers with broadly similar implications include:

PMID: 14585289

PMID: 11925597

PMID: 11551827

PMID: 10473100

PMID: 8242623

Rodney.

[Guest guest]

Rodney posted another mail about studies indicating benefits of Met restriction, this time on met-dependent cancer. Together with his major post recently about MetR, it seems hard indeed not to incorporate a certain met restriction into one's diet.

In a cursory search of the archives of both CR-lists I just found a year-old study not showing MetR benefits. It doesn't proving anything more than there is always a study showing the opposite, but here it is anyway. I can always use it to motivate why I only go for partial MetR because going down to that one gram of methionine per day is just too hard...... // Ulf

From Dr. J Masoro, Dept Physiology, Univ Texas> Quote from Dr. Ed's Laboratory Research paper below:>> ----------> "Recently, methionine restriction has received wide> acclaim including speculation that it may play a role in> FR-induced life extension. In my opinion, work on rats done> in our laboratory makes it unlikely that this speculation is> correct, at least for that species (4). >> We found that a long term 40% reduction in food intake > without a reduction in methionine intake extends the life > of rats to the same extent as a 40% reduction of both food > and methionine intake does (Table 1). Thus, it is clear > that methionine intake need not be decreased for FR to > markedly extend the life of rats.">> ---------> Masoro EJ.> Caloric Restriction and Aging: Controversial Issues.> J Gerontol A Biol Sci Med Sci. 2006 Jan;61(1):14-19.> PMID: 16456190