Studies suggest that gut microbes may promote breast cancer-lifestyle

Microorganisms found in the large intestine and commonly associated with the development of colitis and colon cancer may also be involved in the development of some breast cancers, according to a new study.

The study was led by researchers at the Johns Hopkins Kimmel Cancer Center and its Bloomberg-Kimmel Cancer Immunotherapy Institute. Breast tissue cells exposed to this toxin retain long-term memory and increase the risk of disease.

In a series of laboratory experiments, researchers found that when toxinogenic Bacteroides fragilis (ETBF) was introduced into the intestine or lactiferous duct of mice, it always induced tumor cell growth and metastatic progression. discovered. A description of the work appears in the January 6th issue of the journal Cancer Discovery.

Microorganisms are known to be present in body parts such as the gastrointestinal tract, nasal cavity, and skin, but breast tissue was thought to be sterile until recently, according to a senior research author who is a professor of oncology at Johns Hopkins Medicine. Dr. Diparisharma said.

Sharma states that this study is the first step in demonstrating the involvement of ETBF in the development of breast cancer. How ETBF works throughout the body, whether ETBF is the only driver that directly induces transformation of human breast cells, and / or other microbial flora also has cancer-causing activity in breast tissue. Additional research is needed to determine if you have one.

“Despite multiple established risk factors for breast cancer, such as age, genetic changes, radiation therapy, and family history, women who do not have any of these develop a large number of breast cancers and need to look ahead. Shows, “says Sharma.

“Our study suggests another risk factor for the microbiome. If the microbiome is disturbed or inhabited by toxin-producing microorganisms with carcinogenic function, it is an additional risk factor for breast cancer. May be considered a risk factor. “

Sharma et al. Conducted several experiments to study the role of ETBF. First, they conducted a meta-analysis of clinical data by examining published studies comparing the microbial composition between benign and malignant breast tumors and nipple aspirates of breast cancer survivors and healthy volunteers. It was. B. fragilis was consistently detected in all breast tissue samples and papillary fluid of cancer survivors.

In the lab, the team fed a group of mice by mouth with ETBF bacteria. First, it colonized the intestine. Within 3 weeks thereafter, mouse mammary gland tissue showed observable changes normally present in precancerous ductal hyperplasia.

In additional tests, symptoms such as hyperplasia also appeared within 2-3 weeks of direct injection of ETBF bacteria into the papillae of mice, and cells exposed to toxin were always more rapid than unexposed cells. Toxins that showed tumor progression and were found to have developed more aggressive tumors.

Breast cells exposed to the toxin for 72 hours were able to retain toxin memory, initiate cancer development in various mouse models, and form metastatic lesions. Researchers also found that Notch1 and beta-catenin cell signaling pathways are involved in promoting the role of EBFT in breast tissue.

In clinical studies, researchers have begun looking for changes in the microbial flora of breast cancer patients to see how this affects tumor progression and response to treatment. “We need to make sure we maintain a healthy microbiome, such as eating and exercising healthy and maintaining a correct classification of obesity index,” Sharma said.

In the future, screening for microbiome changes could be as easy as stool sample testing, said Sheetal Parada, a postdoctoral fellow at Johns Hopkins Medicine. “This is just one indicator, and I think there are multiple,” she said.

“If additional bacteria are found that are involved in the development of cancer, the stool can be easily examined and confirmed. Women at high risk of developing breast cancer may have a large population of some of these. . ”

(This story is published from the Wire Agency Feed without changing the text.)

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