Wednesday, August 19, 2009

Precancers 4: Agents that cause precancers are carcinogens

Precancers are the lesions from which cancers develop. Precancers can be easily treated, and when we eliminate precancers, we eliminate the cancers that would have developed from the precancers. This is the message in Precancer: The Beginning and the End of Cancer.

Because cancers emerge from precancers, agents that cause cancer will also cause precancers. Because precancers occur earlier than cancers, we can use observed population increases in specific types of precancers, as an early and sensitive signal indicating that we are being exposed to a carcinogen.

In yesterday's blog, we discussed MGUS (Monoclonal Gammopathy of Undetermined Significance), the precancer for multiple myeloma. There has been speculation that human exposure to pesticides increases the rate of occurrence of multiple myeloma.

If this were the case, we would also expect that human exposure to pesticides would increase the rate of occurrence of MGUS.

In a paper published in June, by Landren et al., the authors showed that men occupationally exposed to pesticides (pesticide applicators) had double the rate of occurrence of MGUS than men in the general population.

Landgren O, Kyle RA, Hoppin JA, Beane Freeman LE, Cerhan JR, Katzmann JA, Rajkumar SV, Alavanja MC. Pesticide exposure and risk of monoclonal gammopathy of undetermined
significance in the Agricultural Health Study. Blood. 2009 Jun 18;113(25):6386-6391.

The effect was stronger with some pesticides (highest increase of MGUS, 5.6-fold, in men exposed to dieldrin) than others.

The increase in MGUS (the precancer for multiple myeloma) among men exposed to pesticides strengthens the hypothesis that pesticides cause multiple myeloma.

This paper provides an example of how epidemiologic data on precancers can be used to warn us when we are being exposed to environmental carcinogens.

In June, 2014, my book, entitled Rare Diseases and Orphan Drugs: Keys to Understanding and Treating the Common Diseases was published by Elsevier. The book builds the argument that our best chance of curing the common diseases will come from studying and curing the rare diseases.

I urge you to read more about my book. There's a generous preview of the book at the Google Books site. If you like the book, please request your librarian to purchase a copy of this book for your library or reading room.
-© 2009 Jules J. Berman, Ph.D., M.D.
tags: common disease, orphan disease, orphan drugs, rare disease, subsets of disease, disease genetics, genetics of complex disease, genetics of common diseases, precancers, precancer, pre-cancerous condition, precancerous condition, preneoplastic lesions, preneoplasia, ien, intra-epithelial neoplasia, intraepithelial neoplasia, intra-epithelial neoplasm, intraepithelial neoplasm, in situ carcinoma, carcinoma in situ, cis, dcis, din, pin, panin, cin, dysplasia, adenoma, preneoplastic, pre-cancer, pre-cancerous, precancerous, early cancer, cancer prevention, cancer detection