Genes Associated with Apoptosis in an Experimental Breast Cancer Model
Gloria M Calaf1, Leodan A Crispin1
1Instituto de Alta Investigación, Universidad de Tarapacá, Arica 1000000, Chile.
Abstract:
Breast cancer remains a leading cause of global mortality. According to international cancer data, significant progress has been made in treating breast cancer; however, metastasis and drug resistance continue to be the primary causes of mortality for many patients. This study investigated the modulation of apoptosis-related genes in response to ionizing radiation and estrogen exposure based on a human breast epithelial cell model (MCF-10F and its transformed variants: Estrogen, Alpha3, Alpha5, Tumor2) previously established, where cells were treated with high linear energy transfer alpha particles, with or without 17β-estradiol. Gene expression profiling was performed using an Affymetrix U133A microarray, and bioinformatic analyses assessed differential expression, estrogen receptor status, and correlations with overall survival. Distinct gene expression patterns emerged across cell lines and tumor subtypes. TP53 expression correlated positively with TP63, BIK, CFLAR, BIRC3, and BCLAF1. TP63, PERP, CFLAR, BCLAF1, GULP1, and BIRC3 were elevated in normal tissue, whereas BIK, PHLDA2, and BBC3 were upregulated in tumors. ER-positive tumors exhibited higher TP63, BIK, BCLAF1, and BBC3 expression, while ER-negative tumors showed increased PERP, CFLAR, BIRC3, and PHLDA2. Notably, elevated BCLAF1 expression was associated with poorer survival in Luminal A patients, and high PHLDA2 expression correlated with reduced survival in Luminal B cases. These findings indicate that resistance to apoptosis is a fundamental mechanism in breast cancer progression and therapeutic evasion. Breast tumors selectively alter the expression of key genes to promote growth, evade apoptosis, and develop therapeutic resistance. The differential expression and correlations of these apoptosis-related genes highlight their potential as molecular targets for future personalized cancer therapies and as valuable biomarkers for prognostic stratification and predicting therapeutic response.
Insights
Breast cancer progression involves altered apoptosis-related gene expression, impacting treatment resistance. Targeting these genes may offer new therapeutic strategies and prognostic biomarkers for personalized breast cancer care.
Area of Science:
- Oncology
- Molecular Biology
- Genetics
Background:
- Breast cancer remains a significant cause of mortality globally.
- Metastasis and drug resistance are primary challenges in breast cancer treatment.
- Understanding apoptosis regulation is crucial for overcoming therapeutic evasion.
Purpose of the Study:
- To investigate the modulation of apoptosis-related genes in breast cancer cells.
- To analyze gene expression changes in response to ionizing radiation and estrogen.
- To identify potential molecular targets and biomarkers for breast cancer therapy.
Main Methods:
- Utilized a human breast epithelial cell model (MCF-10F and variants).
- Treated cells with high linear energy transfer alpha particles and 17β-estradiol.
- Performed gene expression profiling using microarrays and bioinformatic analyses.
Main Results:
- Identified distinct gene expression patterns across cell lines and tumor subtypes.
- Found correlations between specific genes (e.g., TP53, TP63, BCLAF1, PHLDA2) and tumor characteristics.
- Observed associations between elevated BCLAF1 and PHLDA2 expression and poorer patient survival in specific subtypes.
Conclusions:
- Apoptosis resistance is a key mechanism in breast cancer progression and therapeutic evasion.
- Breast tumors selectively alter apoptosis-related gene expression to promote growth and resistance.
- These genes represent potential targets for personalized therapies and prognostic biomarkers.
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