Project description:The goal of this dataset is to compare the gene expression patterns between primary and metastatic tumors Metastatic cancer patients typically have short survival times and their successful treatment represents one of most challenging aspects of patient care. This poor prognostic behavior is likely due to many factors, including increased clonal heterogeneity, multiple drug resistance mechanisms, and the role of the tumor microenvironment. The AURORA US Metastasis Project was established to collect and molecularly characterize specimens from 55 breast cancer (BC) patients representing 51 primary cancers and 102 metastases. The 153 unique tumors were assayed using RNAseq, tumor/germline DNA exomes and low pass whole genome sequencing, and global DNA methylation microarrays. We found intrinsic molecular subtype differences between primary tumors and their matched metastases to be rare in triple negative breast cancer (TNBC)/Basal-like subtype tumors. Conversely, tumor subtype changes were relatively frequent in estrogen receptor positive (ER+) cancers where ~30% of Luminal A cases switched to Luminal B or HER2-enriched (HER2E) subtype. Clonal evolution studies identified changes in expression subtype coincident with DNA clonality shifts, especially involving HER2 amplification and/or the HER2E expression subtype. Microenvironment differences varied according to tumor subtype where ER+/Luminal metastases had lower fibroblast and endothelial cell content, while TNBC/Basal-like metastases showed a dramatic decrease in adaptive immunity. In 17% of metastatic tumors, we identified DNA methylation and/or focal DNA deletions near HLA-A that were associated with its significantly reduced expression, and with lower immune cell infiltrates. We also identified low immune cell features in brain and liver metastases when compared to other metastatic sites, even within the same patient. These findings have direct implications for the treatment of metastatic breast cancer patients with immune- and HER2-targeting therapies and suggest potential novel therapeutic avenues for the improvement of outcomes for some MBC patients.
Project description:Patients with metastatic breast cancer (MBC) typically have short survival times and their successful treatment represents one of the most challenging aspects of patient care. This poor prognostic behavior is in part due to molecular features including increased tumor cell clonal heterogeneity, multiple drug resistance mechanisms, and alterations of the tumor microenvironment. The AURORA US Metastasis Project was established with the goal to identify molecular features specifically associated with metastasis. We therefore collected and molecularly characterized specimens from 55 metastatic breast cancer (BC) patients representing 51 primary cancers and 102 metastases. The 153 unique tumors were assayed using RNAseq, tumor/germline DNA exomes and low pass whole genome sequencing, and global DNA methylation microarrays. We found intrinsic molecular subtype differences between primary tumors and their matched metastases to be rare in triple negative breast cancer (TNBC)/Basal-like subtype tumors. Conversely, tumor subtype changes were relatively frequent in estrogen receptor positive (ER+) cancers where ~30% of Luminal A cases switched to Luminal B or HER2-enriched (HER2E) subtypes. Clonal evolution studies identified changes in expression subtype coincident with DNA clonality shifts, especially involving HER2 amplification and/or the HER2E expression subtype. In contrast, we found remarkable conservation of cancer-associated DNA hypermethylation profiles within primary tumor-metastasis pairs. We further found evidence for ER-mediated downregulation of genes involved in cell-cell adhesion in metastases. Microenvironment differences varied according to tumor subtype where ER+/Luminal metastases had lower fibroblast and endothelial cell content, while TNBC/Basal-like metastases showed a dramatic decrease in B cells and T cells. In 17% of metastatic tumors, we identified DNA hypermethylation and/or focal DNA deletions near HLA-A that were associated with its significantly reduced expression, and with lower immune cell infiltrates. We also identified low immune cell features in brain and liver metastases when compared to other metastatic sites, even within the same patient. These findings have implications for the treatment of metastatic breast cancer patients with immune- and HER2-targeting therapies and suggest potential novel therapeutic avenues for the improvement of outcomes for some patients with MBC
Project description:Patients with metastatic breast cancer (MBC) typically have short survival times and their successful treatment represents one of the most challenging aspects of patient care. This poor prognostic behavior is in part due to molecular features including increased tumor cell clonal heterogeneity, multiple drug resistance mechanisms, and alterations of the tumor microenvironment. The AURORA US Metastasis Project was established with the goal to identify molecular features specifically associated with metastasis. We therefore collected and molecularly characterized specimens from 55 metastatic breast cancer (BC) patients representing 51 primary cancers and 102 metastases. The 153 unique tumors were assayed using RNAseq, tumor/germline DNA exomes and low pass whole genome sequencing, and global DNA methylation microarrays. We found intrinsic molecular subtype differences between primary tumors and their matched metastases to be rare in triple negative breast cancer (TNBC)/Basal-like subtype tumors. Conversely, tumor subtype changes were relatively frequent in estrogen receptor positive (ER+) cancers where ~30% of Luminal A cases switched to Luminal B or HER2-enriched (HER2E) subtypes. Clonal evolution studies identified changes in expression subtype coincident with DNA clonality shifts, especially involving HER2 amplification and/or the HER2E expression subtype. In contrast, we found remarkable conservation of cancer-associated DNA hypermethylation profiles within primary tumor-metastasis pairs. We further found evidence for ER-mediated downregulation of genes involved in cell-cell adhesion in metastases. Microenvironment differences varied according to tumor subtype where ER+/Luminal metastases had lower fibroblast and endothelial cell content, while TNBC/Basal-like metastases showed a dramatic decrease in B cells and T cells. In 17% of metastatic tumors, we identified DNA hypermethylation and/or focal DNA deletions near HLA-A that were associated with its significantly reduced expression, and with lower immune cell infiltrates. We also identified low immune cell features in brain and liver metastases when compared to other metastatic sites, even within the same patient. These findings have implications for the treatment of metastatic breast cancer patients with immune- and HER2-targeting therapies and suggest potential novel therapeutic avenues for the improvement of outcomes for some patients with MBC
Project description:Purpose Triple negative breast cancer (TNBC) is the most aggressive breast cancer subtype with no targeted treatment available. Our previous study identified 38 TNBC-specific genes with altered expression in tumour samples compared to normal samples. This study aimed to identify whether DNA methylation contributed to these gene expression changes in the same breast cancer cohort. Additionally, we aimed to identify a whole genome methylation profile that contributes to the progression from primary breast tumour to lymph node metastasis. Methods We used the DNA of 23 primary TNBC samples, 12 matched lymph node metastases, and 11 matched normal adjacent tissues to perform 450K Illumina methylation arrays. The results were validated in an independent cohort of 70 primary TNBC samples. Results The gene expression of 16/38 TNBC-specific genes was associated with significantly altered methylation. Furthermore, altered methylation of 18 genes associated with lymph node metastasis was identified and validated in an independent cohort. Additionally, novel methylation changes between primary tumours and lymph node metastases, as well as those associated with survival were identified. Conclusion This study has shown that DNA methylation plays an important role in altered gene expression patterns of TNBC-specific genes and is the first study to perform whole genome DNA methylation analysis that includes matched lymph node metastases in this breast cancer subtype. This novel insight into the progression of TNBC to secondary cancers may provide potential prognostic indicators for this hard-to-treat breast cancer subtype. study cohort
Project description:Purpose Triple negative breast cancer (TNBC) is the most aggressive breast cancer subtype with no targeted treatment available. Our previous study identified 38 TNBC-specific genes with altered expression in tumour samples compared to normal samples. This study aimed to identify whether DNA methylation contributed to these gene expression changes in the same breast cancer cohort. Additionally, we aimed to identify a whole genome methylation profile that contributes to the progression from primary breast tumour to lymph node metastasis. Methods We used the DNA of 23 primary TNBC samples, 12 matched lymph node metastases, and 11 matched normal adjacent tissues to perform 450K Illumina methylation arrays. The results were validated in an independent cohort of 70 primary TNBC samples. Results The gene expression of 16/38 TNBC-specific genes was associated with significantly altered methylation. Furthermore, altered methylation of 18 genes associated with lymph node metastasis was identified and validated in an independent cohort. Additionally, novel methylation changes between primary tumours and lymph node metastases, as well as those associated with survival were identified. Conclusion This study has shown that DNA methylation plays an important role in altered gene expression patterns of TNBC-specific genes and is the first study to perform whole genome DNA methylation analysis that includes matched lymph node metastases in this breast cancer subtype. This novel insight into the progression of TNBC to secondary cancers may provide potential prognostic indicators for this hard-to-treat breast cancer subtype. Validation cohort (70 IDC TNBC samples)
Project description:Brain metastatic disease occurs in 10-30% of metastatic breast cancer cases. The incidence of brain metastases is increasing with median overall survival < 2 years for patients. In order to better characterize oncogenic pathway activity pertinent to breast cancer brain metastasis, exome capture RNA sequencing was carried out on patient matched primary breast with brain metastatic tumor samples for 45 cases of breast cancer brain metastasis (N= 90 samples). Here, exome capture RNA sequencing data is deposited as sequencing batch corrected log2 transformed trimmed M of means (TMM) normalized counts per million (CPM) (log2(TMM-CPM +1) gene expression values (n=16,714 protein coding genes; N=90 tumor samples).
Project description:Brain metastatic disease occurs in 10-30% of metastatic breast cancer cases. The incidence of brain metastases is increasing with median overall survival < 2 years for patients. In order to better characterize oncogenic pathway activity pertinent to breast cancer brain metastasis, exome capture RNA sequencing was carried out on patient matched primary breast with brain metastatic tumor samples for 45 cases of breast cancer brain metastasis (N= 90 samples). Here, exome capture RNA sequencing data is deposited as sequencing batch corrected log2 transformed trimmed M of means (TMM) normalized counts per million (CPM) (log2(TMM-CPM +1) gene expression values (n=16,714 protein coding genes; N=90 tumor samples).
Project description:Purpose: Advanced breast cancer leads to significantly higher mortality due to metastasis. The goal of this work is to screen and study the deregulated epigenetic regulators to identify the novel targets for the treatment of metastatic breast cancer. Methods:RNA-Seq analysis of matched primary and metastatic breast samples to detect the deregulated epigenetic regulators. Live imaging system was applied to modulate metastatic tumor growth in vivo. Results: we identified that deregulated CECR2 was associated with breast cancer metastasis by RNA sequencing analysis of the matched primary and metastatic breast cancer samples from 13 patients. CECR2 knockout significantly decreased breast cancer metastasis in both immunocompromised and immunocompetent mice models. RNA-seq analysis showed that gene set "response to NF-κB signaling" was significantly decreased by CECR2 depletion in breast cancer cells. Mechanistically, CECR2 formed a complex with RELA on NF-κB target gene promoters to activate target gene expression. Furthermore, CECR2 played a key role in tumor associated macrophage recruitment and polarization, which regulates the antitumor immunity in microenvironment. Conclusions: our work identified and characterized a novel epigenetic regulator CECR2 in regulating breast cancer metastasis, and can serve as a potential target for the treatment of metastatic breast cancer.
Project description:Purpose: Advanced breast cancer leads to significantly higher mortality due to metastasis. The goal of this work is to screen and study the deregulated epigenetic regulators to identify the novel targets for the treatment of metastatic breast cancer. Methods:RNA-Seq analysis of matched primary and metastatic breast samples to detect the deregulated epigenetic regulators. Live imaging system was applied to modulate metastatic tumor growth in vivo. Results: we identified that deregulated CECR2 was associated with breast cancer metastasis by RNA sequencing analysis of the matched primary and metastatic breast cancer samples from 13 patients. CECR2 knockout significantly decreased breast cancer metastasis in both immunocompromised and immunocompetent mice models. RNA-seq analysis showed that gene set "response to NF-κB signaling" was significantly decreased by CECR2 depletion in breast cancer cells. Mechanistically, CECR2 formed a complex with RELA on NF-κB target gene promoters to activate target gene expression. Furthermore, CECR2 played a key role in tumor associated macrophage recruitment and polarization, which regulates the antitumor immunity in microenvironment. Conclusions: our work identified and characterized a novel epigenetic regulator CECR2 in regulating breast cancer metastasis, and can serve as a potential target for the treatment of metastatic breast cancer.