Polymorphisms in circadian genes, night work and breast cancer: results from the GENICA study.

Objectives: The role of genetic variants and environmental factors in breast cancer etiology has been intensively studied in the last decades. Gene-environment interactions are now increasingly being investigated to gain more insights into the development of breast cancer, specific subtypes, and therapeutics. Recently, night shift work that involves circadian disruption has gained rising interest as a potential non-genetic breast cancer risk factor.

Night work and breast cancer estrogen receptor status--results from the German GENICA study.

Objectives: The potential mechanisms that link night-shift work with breast cancer have been extensively discussed. Exposure to light at night (LAN) depletes melatonin that has oncostatic and anti-estrogenic properties and may lead to a modified expression of estrogen receptor (ER) α. Here, we explored the association between shift work and breast cancer in subgroups of patients with ER-positive and -negative tumors.

Night work and breast cancer - results from the German GENICA study.

Objectives: Some epidemiological and animal data indicate that night work might increase the risk for breast cancer. We have investigated the risk in a German population-based case-control study known as GENICA (gene environment interaction and breast cancer).

Methods: The GENICA study involved interviews to assess shift work information in 857 breast cancer cases and 892 controls.