Recent research on bisphenol A (BPA) and breast cancer Bisphenol A (BPA) causes endocrine disruption and exposure to BPA may increase the risk of breast cancer. Food packaging and containers are a major source of BPA. BPA has been shown to induce breast cancer cell proliferation. Chronic low-dose exposure to BPA in adult mice promotes tumor progression in vivo. BPA causes proliferation of mammary cells in BRCA1 gene deficient mice, leading to hyperplasia. Finally, BPA can reduce the effectiveness of certain chemotherapy regimens. Therefore, it makes sense to take reasonable measures to limit exposure to BPA. BPA is primarily derived from food packaging and containers BPA is prevalent. BPA is one of the most heavily produced chemicals worldwide, and it can be detected in over 90% of human bodily fluids. BPA is widely used in the production of consumer products, polycarbonate plastics and epoxy resins. BPA is used in epoxy coatings for the interior of canned foods and canned sodas. BPA in polycarbonate plastic bottles and some metal water bottles with reusable liners can permeate the water in which they are stored. Heat can increase BPA leaching from food and beverage containers. In addition, BPA can be found in many consumer products consisting of polycarbonate plastics, such as baby bottles, sports equipment, eyeglass lenses, compact discs, and implantable medical devices. BPA is a component of some plastic plumbing, dental sealants, and paint resins. In addition, BPA has been found on many papers, including cash register receipts, documents, food packaging, cigarette filters and U.S. paper money. BPA in canned and packaged foods is plentiful. In one study, healthy volunteers ate 12 ounces of fresh soup for five consecutive days, followed by a two-day metabolic period, and then followed by five consecutive days of canned soup. The results showed a 20-fold increase in urinary BPA levels when eating canned soup compared to when eating fresh soup, but the increase was not sustained. This short-term increase in BPA levels is not known for human health. BPA induces proliferation of breast cancer cells BPA promotes proliferation of hormone receptor positive breast cancer cells by upregulating the expression of cell cycle-promoting genes and downregulating the expression of anti-proliferative genes. Cytological studies have also shown that under certain circumstances, BPA increases tumor size and grading changes in high-risk breast tissue. Developmental exposure to BPA affects breast development There have been many studies using animal models to study the effects of exposure to BPA. One such study was conducted in rats exposed to low doses of BPA or hexestrol (DES) during pregnancy and lactation, and found that both substances delayed mammary differentiation and altered milk production and milk composition. Hexestrol has been shown to increase the risk of breast cancer. In another study, designed to examine the association between BPA and the development of breast cancer, i.e., prenatal exposure to low levels of BPA, the authors added BPA to the drinking water of breeding mice and analyzed the mammary glands of the female offspring of these mice during puberty. The authors concluded that perinatal exposure to BPA alters the long-term hormonal response and may increase the risk of breast cancer. Prolonged exposure of adult mice to low doses of BPA promotes tumor development Another study looked at the effects of long-term oral BPA exposure on mammary tumors in adult mice. Mice with tumor HER2 overexpression were given separate drinking water containing different doses of BPA. Only low doses of BPA were found to significantly accelerate mammary tumor development and metastasis. BPA induces cell proliferation in BRCA1 gene deficient mice The biological response to BPA seems to depend to some extent on the genetic makeup of the individual. A study aimed at exploring the relationship between BRCA1 gene deletion and BPA-mediated cell proliferation reported that BRCA1 gene deletion enhances BPA-induced cell proliferation (BPA levels are higher than those currently seen in humans routinely exposed to BPA). BPA stimulates the proliferation of mammary cells in BRCA1 gene mutant mice, leading to abnormal hyperplasia. The authors conclude that the cellular biological response to BRCA1 gene defects may be environmentally relevant, such as exposure to BPA. BPA interferes with chemotherapy efficacy Low levels of BPA have been shown to reduce the efficacy of the chemotherapeutic agents adriamycin (Adriamycin), cisplatin, and vincristine on estrogen receptor-positive (ER +) and triple-negative (ER-/PR-/HER2-) breast cancer cells. Despite its estrogenic properties, BPA does not affect cancer cells through estrogen receptor-mediated effects. Instead, BPA appears to influence the effect of chemotherapy on cancer cells by increasing the expression of anti-apoptotic proteins (which prevent programmed cell death). Reducing exposure to BPA has important implications The role of BPA on human health is controversial. There are two schools of thought, with some experts arguing that the health effects of BPA exposure may be negligible. The Food and Drug Administration (FDA) issued an update to its policy on BPA in March 2012, concluding that the use of BPA in containers is, for now, relatively safe, but that new evidence will be carefully considered. However, the European side of the regulation is more stringent on potential BPA exposure. Those who support that BPA exposure does not pose a health hazard do so by using less realistic experiments as evidence, such as injecting rats with high doses of BPA (while most people are verbally exposed to BPA), which is rapidly metabolized and converted to bisphenol A-glucuronide, a chemical that is easily excreted in urine and is a harmless, water-soluble substance. However, the two studies we mentioned above, both in volunteers given low doses of BPA orally and in animals, confirmed that BPA has a cancer-promoting effect. And the experiments mentioned earlier confirmed that it is possible to produce high levels of BPA in the urine simply by eating canned soup every day. therefore, we believe it makes sense to reduce exposure to BPA by taking measures during chemotherapy. For example, avoid canned foods, canned sodas, polycarbonate plastic bottles and food container use. Some plastic containers (usually at the bottom) are marked with a triangle-shaped icon, and plastics marked with a number 7 should be avoided because they contain BPA. Some plastics marked with a number 3 also contain BPA.