Question

As the cancer expert in the Biology Department at your school, NBC news contacts you to discuss the effects of bisphenol A (BPA) exposure on cancer risk. can cure leukemia can cure leukemiaThe reporter is very interested as she has read several articles on this topic. In particular she wants you to explain the following:

Is there sufficient evidence linking BPA to cancer? If so, is the risk the same of all types of cancer or are their particular types of cancer that are know to be associated with BPA exposure?

Answer 1

BPA is a common chemical in homes today. It is the chemical building block for clear polycarbonate plastic, which is used in bottles, in the linings of metal food cans—including cans containing infant formula, and in other food storage containers. It is also found in paper receipts. And it’s getting into our bodies. Due to its phenolic structure BPA has been shown to interact with estrogen receptors and to act as agonist or antagonist via estrogen receptor (ER) dependent signalling pathways. Therefore, BPA has been shown to play a role in the pathogenesis of several endocrine disorders including female and male infertility, precocious puberty, hormone dependent tumours such as breast and prostate cancer and several metabolic disorders including polycystic ovary syndrome (PCOS). More than 150 studies have shown that BPA disrupts the hormone system and causes changes that mirror properties of cancer cells. One recent example is a study in the Sept. 1, 2011, issue of Carcinogenesis , which found that breast cells exposed in vitro to BPA undergo structural changes that enable them to proliferate like cancer cells. Exposure to BPA affects the mTOR pathway, which regulates cell growth, proliferation, motility, survival, protein synthesis, and transcription. When the mTOR signal is turned off, cancer cells do not survive, but once mTOR is activated, cells can proliferate.
BPA is expected to have effects on ER function in addition to other nuclear hormone receptors and most of the studies on BPA action have focused on hormone sensitive tissues. The ubiquitous presence of BPA in the environment, concomitant with the increased prevalence of endocrine-related cancers
According to the WHO's INFOSAN, carcinogenicity studies conducted under the US National Toxicology Program, have shown increases in leukemia and testicular interstitial cell tumors in male rats. However, according to the note "these studies have not been considered as convincing evidence of a potential cancer risk because of the doubtful statistical significance of the small differences in incidences from controls.Higher susceptibility to breast cancer has been found in many studies of rodents and primates exposed to BPA.