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Charlie Bell, CEO of McDonald restaurants, died of colorectal cancer at the age of 44 on Jan 17, 2005. The Australian is an advocate of his own product who would eat McDonald's for breakfast. He worked for McDonald's at age of 15 and had hamburgers since then. Are meat sandwiches killers? If true, please, stop eating beef meat. If false, please, stop the bad news. My present view of the meat issue is given in this article: Red meat and colon cancer: Should we become vegetarians, or can we make meat safer? (summer 2011, but not written for lay people, I am afraid). Easier to read, try my conference presentation: Red meat and colon cancer: Should we become vegetarians, or can we make meat safer? (a huge file: 3 Mo). I was recently invited to participate in the 22 experts workgroup at IARC (a WHO agency) who decided that consumption of processed meat is carcinogenic
Long ago, in 1989, I choose to study cancer prevention. One sabbatical year with smart Bob Bruce in Toronto, put to me on the rails of cancer research, after 15 years of bacteriological research . Since, I look for the effect of food on the colorectal carcinogenesis, the anti-cancer diet. Prevention is better than cure: every day, one hundred people learn they have a colon cancer in France. It's often too late, and fifty will die from it. My Florence's mother died like that, much too young.
I was very lucky, and made significant discoveries. Notably, with Bob, we could show that caramel (cooked sugar), and cooked casein can promote colon carcinogenesis in rats and mice (it was dry cooking 2h at 180°C). Then, with Fabrice Pierre and Sylviane Taché, we showed the promoting effect of beef meat, likely because it contains the red heminic iron. The good news is that it is easy to inhibit heme (or haem) promotion, provided the diet is loaded with calcium or other nutrients (which explains why nobody was able to demonstrate red meat carcinogenicity before our 2004 article). Then, we turned to the promotion of colorectal cancer by processed meat intake (2008 review). We could show that cured meat promotes colon carcinogenesis in rats (07/2010), but this toxic effect can be inhibited with new additives or processes (WCRF conference, London 12 sept 2010, Cured Meat Promotion of Colon Carcinogenesis is Suppressed by Calcium and Tocopherol), now published in Rats Bastide, Nutrition and Cancer, 2017) and in humans (only vit.E and Ca++ effect) Pierre, AJCN 2013
Want a true simple message? Jump to Denis' interview by Psychology-Today: Meat and Cancer (March 2011).
I also cogitate on two problems: (1) How good are rodent models of carcinogenesis in predicting efficacy in humans? (I make use of meta-analysis of studies in rats and mice) ; (2) Which early marker of colorectal cancer is the best, ACF or MDF? May be more important, with Géraldine Parnaud, Ginette et Sylviane, we made the serendipitous discovery that PEG, a common laxative agent, is a very powerful anticancer agent: Will everybody have to eat PEG to clear colon cancer from earth? (my secret hope is: "No", but... I'd love my discovery to be useful to some people at least)
Discovery of a major new anticancer agent, PEG
I discovered by serendipity that polyethyleneglycol (PEG) is a new anti-cancer agent. It is very powerful in preclinical models (rats, mice). It is cheap, and shows no toxicity in humans: the jack pot! It is not known yet if PEG could prevent cancer in human beings. How did we find it? A big piece of chance, since we were looking for something else. The full story is given in French: Peg & Bacon.pdf. We thus showed in 1999 that PEG 8000, a polymer already given to people (as a food additive and laxative), completely prevents the occurence of cancer in rats, and powerfully reduces polyps and ACF in carcinogen-initiated rats. PEG is ten times more powerful than previously known chemopreventive agents (see their ranking). We now have a PEG anti-cancer effect patent in the USA, after an USPTO appeal. PEG anti-cancer effect is also patented in France and in Europe. I wrote more than five scientific publications on PEG effect: first one in [Carcinogenesis], major one in [Cancer Research]. We also discovered, and patented, that PLU was much more potent than PEG, and published it in the [Int.J.Cancer], and we could explain, in part, the mechanism in the [British J.Cancer]. PEG protection is currently explored in a clinical trial in American volunteers (PEG trial on NCI site), according to what was decided by the RAPID programm of National Cancer Institute. I really hope that PEG will lead to a significant reduction of cancer burden.
These researches' impact is not easy to measure: The WHO decision that processed meat is carcinogenic (grp. 1) and red meat probably carcinogenic (grp. 2A) comes, in part, from my team's results (oct.2015). About 100 scientific articles in international journals have been published. Some twenty reviews (e.g., CEBP) and book chapters (e.g., Food & Cancer, Riboli ed., and Fonctional Foods, Roberfroid ed.). Most papers are in "good" journals (impact factor > 2). One of them is in the New Engl. J Med. (impact 30), four others in Cancer Research (impact 9). These articles, together, had been quoted more than 800 times (2008): Not so bad, but not outstanding (my Florence has been quoted more than 2500 times, but she has one of INRA's best score!). I start to put theses papers onUniversity of Toulouse Open Archive. I made a hundred scientific communications in international congresses, of which a third on invitation (all paid expenses!). I also try to communicate with lay public, to explain them how diet can prevent cancer (in French). I build a free access database on the Internet (> 1.5 thousand requests/day). This chemoprevention database on INRA/NACRe server has a mirror site on Free chemoprevention, and is discussed on tumor.free.fr site.
These researches are conducted in the Prevention and Promotion of Carcinogenesis by Food team (PPCF PPCA) I lead in ToxAlim research center. ToxAlim belongs to INRA but the team is located on the ENVT campus.
Before working against cancer, I have been working for 15 years on antibiotics (residues and additives) and antimicrobial resistance in the intestinal microflora of humans and animals. It started in 1976, when I arrived in Toulouse after "Agro-Paris Tech" and the military service. Thanks to Raibaud & Ducluzeau, I "invented" a new animal model (see below), and I could explain why there are resistant bacteria in our intestine: because one swallows some, quite simply! To show it, I daily followed the number of resistant bacteria in the stools of volunteers who ate their usual diet, then, during three weeks, a sterile diet. All foods were "cooked and reheated": for this "sterile" period, resistant bacteria disappeared from stools. Antibiotic Resistance from Food [New Engl.J.Med.] . Since, I started cancer research, but bacterial resistances became very à.la.mode. Then, sporadically, I am requested as a resistant bacteria expert. For instance, I participated in a European comitee which evaluated the famous Bt corn, a GMO.
- Invention of an animal model: a mouse with a human flora.
I had the idea to study the effect of antibiotic residues on the gut flora of human, in germ-free mice associated with human flora [HFA mice]. The minimal selecting dose can thus be determined in vivo (Free reprint on HAL Corpet 1989, Minimum antibiotic levels for selecting a resistance plasmid in a gnotobiotic animal model. This model is recommended in the European (European Commission), American (Food and Drug Administration) and world (Codex, JECFA WHO) directives to establish the amount without effect and the Maximum Residue Limit (MRL) for veterinary antibiotics. It is currently developed with the AFSSA of Fougères (J.M. Poul).
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