Molecular Changes During Breast Cancer and Mechanisms of Endocrine Therapy Resistance

Area of Science:

• Oncology
• Molecular Biology
• Endocrinology

Background:

• Estrogen receptors (ERs) are crucial in ~75% of breast cancers, influencing tumor development and progression.
• ERs exhibit both genomic and nongenomic activities, impacting cell growth and survival pathways.
• Endocrine therapies target estrogen's growth-promoting effects, but resistance is a significant clinical challenge.

Purpose of the Study:

• To review the fundamental biology of estrogen receptors (ERs).
• To elucidate the complex mechanisms underlying endocrine therapy resistance in ERs-positive breast cancer.
• To discuss the clinical implications of ER biology and resistance mechanisms.

Main Methods:

• Literature review of scientific articles and clinical studies.
• Analysis of genomic and nongenomic ER signaling pathways.
• Examination of resistance mechanisms including pathway deregulation and tumor microenvironment factors.

Main Results:

• ERs mediate breast cancer growth via nuclear and membrane-associated signaling.
• Endocrine resistance can be de novo or acquired, involving multiple complex mechanisms.
• Tumor microenvironment and signaling pathway crosstalk contribute to treatment failure.

Conclusions:

• A comprehensive understanding of ER biology is essential for breast cancer management.
• Targeting ERs and overcoming endocrine resistance are key areas for therapeutic advancement.
• Further research into resistance mechanisms will guide the development of novel treatment strategies.