Article Abstract:
Estrogen receptors in breast cells appear to decline during the luteal phase of the menstrual cycle while the level of progesterone receptors appears to be the same during the follicular and luteal phases. Previous studies on cells from the endometrial lining of the uterus found that both estrogen and progesterone receptors decline in the luteal phase. Levels of estrogen and progesterone receptors in breast cells were measured in 42 healthy women using fine-needle aspiration biopsy. Estrogen receptor was detected in 68% of samples drawn during the follicular phase and in 32% of samples drawn during the luteal phase. However, progesterone receptor was detected in about 80% of the samples drawn during both phases.
User Contributions:
Comment about this article or add new information about this topic:
Article Abstract:
The proliferation of breast cells may vary according to the stage of the menstrual cycle. Researchers performed fine needle aspiration biopsy to obtain breast epithelial cells from 47 healthy, menstruating women without breast disease. More breast cells were found during the luteal phase of the menstrual cycle than during the follicular phase. Higher levels of progesterone were associated with greater proliferation of breast cells, indicating a stimulating effect of progesterone. Such findings may improve understanding of cancer risk and hormone treatment.
User Contributions:
Comment about this article or add new information about this topic:
Article Abstract:
The expression of p53 and markers for apoptosis in breast tissue during long-term hormone therapy in cynomolgus monkeys is analyzed. Alternative regimens for hormonal therapy have different effects on p53 expression and apoptotic activity within the breast and a possible mechanism to explain the increased risk for breast cancer can be a combined effect of increased proliferation and decreased apoptosis.
User Contributions:
Comment about this article or add new information about this topic: