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Published on: January 8, 2015
Implications of ESR1 Mutations in Hormone Receptor-Positive Breast Cancer
Tomás Reinert1,2, Rodrigo Gonçalves3, José Bines4
1Hospital do Câncer Mãe de Deus, Porto Alegre, Brazil.
Opinion Statement:
Endocrine treatment resistance eventually develops during adjuvant and even more often during hormonal treatment for advanced breast cancer (ABC). An ESR1 gene mutation, which encodes for the estrogen receptor (ER) protein, is one of the potential mechanisms of therapy resistance. The ESR1 mutations result in conformational changes in the ER leading to subsequent estrogen-independent transcriptional activity. These mutations are found at a lower level in early stage when compared to metastatic BC, more often through selective pressure after aromatase inhibitor (AI) treatment. Recent studies have explored the role of ESR1 mutations as potential prognostic and predictive biomarkers and showed that ESR1 mutations are likely associated with a more aggressive disease. However, definitive associations with outcome in order to make a specific treatment recommendation are yet to be found. The development of targeted therapy directed to ESR1-mutated clones is an appealing concept, and preclinical and clinical works are in progress. ESR1 mutations represent an exciting field with a rapidly increasing number of recent publications that will likely advance the knowledge of treatment resistance mechanisms and pave the way into more individualized patient endocrine treatment.
Insights
Estrogen receptor 1 (ESR1) gene mutations can cause endocrine treatment resistance in advanced breast cancer (ABC). Research is exploring these mutations as biomarkers and targets for new therapies.
Area of Science:
- Oncology
- Genetics
- Molecular Biology
Background:
- Endocrine treatment resistance is a significant challenge in managing advanced breast cancer (ABC).
- Estrogen receptor 1 (ESR1) gene mutations are implicated as a key mechanism driving this resistance.
- These mutations alter estrogen receptor (ER) conformation, leading to estrogen-independent activity.
Purpose of the Study:
- To review the role of ESR1 mutations in endocrine therapy resistance in breast cancer.
- To discuss the potential of ESR1 mutations as prognostic and predictive biomarkers.
- To highlight emerging targeted therapies for ESR1-mutated breast cancer.
Main Methods:
- Literature review of recent studies on ESR1 mutations in breast cancer.
- Analysis of the association between ESR1 mutations, treatment resistance, and disease aggressiveness.
- Exploration of preclinical and clinical data on targeted therapies.
Main Results:
- ESR1 mutations are more prevalent in metastatic breast cancer, particularly after aromatase inhibitor treatment.
- Emerging evidence suggests ESR1 mutations correlate with a more aggressive disease phenotype.
- Definitive prognostic and predictive associations require further investigation.
Conclusions:
- ESR1 mutations are a critical factor in endocrine resistance in breast cancer.
- Targeted therapies against ESR1-mutated clones represent a promising avenue for personalized treatment.
- Continued research in this area is vital for advancing breast cancer care.
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