Hypomethylation Of Cdk5 Protein Offers Possible Causal Link Between BPA and Medullary Thyroid CancerSUMMARY: Over-expression of Cdk5 protein causes medullary thyroid carcinoma in rats. BPA causes hypomethylation (over-expression) of Cdk5-related genes. Could BPA exposure cause epigenetic changes that promote medullary thyroid carcinoma?
By Lewis Perdue
Copyright 2013, All rights reserved
Bisphenol A (BPA) has been suspected in many studies(1-5) of disrupting thyroid hormones.
In addition, BPA exposure in pregnant mice has been shown to induce epigenetic changes in offspring(6).
Various mechanisms have been proposed including hypomethlyation in early development, specifically, "CpG methylation also was decreased at another metastable locus, the CDK5 activator-binding protein (Cabp IAP)(7) .
This previous work with BPA as a thyroid endocrine distruptor may offer significant insight into the origins of medullary thyroid carcinoma (MTC) when viewed in light of a recent accidental discovery in Texas..
According to a study published Oct 14 in Cancer Cell(8) research at The University of Texas Southwestern's Department of Psychiatry were investigating the origins of dementia and created a transgenic mouse that over-expressed the Cdk5 protein they felt could be connected with myloid plaques.
The study, run by Dr. James Bibb, Associate Professor of Psychiatry and Neurology and Neurotherapeutics, quickly found that the mice had all developed medullary thyroid carcinoma.