Single-Cell mRNA Analysis for the Identification of Molecular Pathways of IRF1 in HER2+ Breast Cancer
Laura Vilardo1, Paride Pelucchi1, Antonia Brindisi1
1Institute of Biomedical Technologies, National Research Council, 20054 Milano, Italy.
Abstract:
Clonally established tumor cell lines often do not recapitulate the behavior of cells in tumors. The sequencing of a whole tumor tissue may not uncover transcriptome profiles induced by the interactions of all different cell types within a tumor. Interferons for instance have a vast number of binding sites in their target genes. Access to the DNA binding sites is determined by the epigenomic state of each different cell type within a tumor mass. To understand how genes such as interferons appear to have both tumor-promoting and tumor-inhibiting functions, single-cell transcript analysis was performed in the breast cancer tissue of HER2+ (epidermal growth factor receptor 2) patients. We identified that potential antagonistic oncogenic activities of cells can be due to diverse expression patterns of genes with pleiotropic functions. Molecular pathways both known and novel were identified and were similar with those previously identified for patients with rheumatoid arthritis. Our study demonstrates the efficacy in using single-cell transcript analysis to gain insight into genes with apparent contradictory or paradoxical roles in oncogenesis.
Insights
Single-cell transcript analysis reveals diverse gene expression in HER2+ breast cancer, explaining how genes like interferons can promote or inhibit tumors. This method uncovers complex cellular interactions within tumors.
Area of Science:
- Oncology
- Genomics
- Molecular Biology
Background:
- Tumor cell lines may not accurately reflect in vivo tumor behavior.
- Whole-tissue sequencing can miss cell-type-specific transcriptome profiles and epigenetic regulation.
- Genes like interferons exhibit dual roles in cancer, necessitating a deeper understanding of their context-dependent functions.
Purpose of the Study:
- To investigate the paradoxical roles of genes, such as interferons, in oncogenesis within HER2+ breast cancer.
- To explore how cell-cell interactions and epigenomic states influence gene expression and function within a tumor.
- To identify novel molecular pathways and understand diverse expression patterns contributing to antagonistic oncogenic activities.
Main Methods:
- Single-cell transcript analysis was performed on breast cancer tissue from HER2+ patients.
- Analysis focused on identifying diverse gene expression patterns and their relationship to cellular interactions.
- Epigenomic states and DNA binding sites of target genes were considered in relation to gene expression.
Main Results:
- Identified diverse expression patterns of genes with pleiotropic functions, leading to antagonistic oncogenic activities.
- Uncovered novel molecular pathways and confirmed similarities to pathways found in rheumatoid arthritis.
- Demonstrated that single-cell analysis can elucidate the complex roles of genes in cancer development.
Conclusions:
- Single-cell transcript analysis is effective for understanding genes with contradictory roles in oncogenesis.
- Tumor heterogeneity and cell-type-specific gene expression are critical for understanding cancer progression.
- The findings provide insights into the complex interplay of genes and pathways in HER2+ breast cancer.
