Project description:Metastasis is responsible for the majority of deaths in a variety of cancer types, including breast cancer. Although several factors or biomarkers have been identified to predict the outcome of patients with breast cancer, few studies have been conducted to identify metastasis-associated biomarkers. Quantitative iTRAQ proteomics analysis was used to detect differentially expressed proteins between lymph node metastases and their paired primary tumor tissues from 23 patients with metastatic breast cancer. Immunohistochemistry was performed to validate the expression of two upregulated (EpCAM, FADD) and two downregulated (NDRG1, αB-crystallin) proteins in 190 paraffin-embedded tissue samples. These four proteins were further analyzed for their correlation with clinicopathological features in 190 breast cancer patients. We identified 637 differentially regulated proteins (397 upregulated and 240 downregulated) in lymph node metastases compared with their paired primary tumor tissues. Furthermore, bioinformatics analysis using GEO profiling confirmed the difference in the expression of EpCAM between metastases and primary tumors tissues. Two upregulated (EpCAM, FADD) and two downregulated (NDRG1, αB-crystallin) proteins were associated with the progression of breast cancer. Obviously, EpCAM plays a role in the metastasis of breast cancer cells to the lymph node. We further identified αB-crystallin as an independent biomarker to predict lymph node metastasis and the outcome of breast cancer patients.
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:Whole genome bisulphite sequencing of 2 human breast cancer cell lines representing a breast primary tumor and a matched lymph node metastasis.
Project description:Whole genome bisulphite sequencing of 2 human breast cancer cell lines representing a breast primary tumor and a matched lymph node metastasis. Sequencing of bisulfite converted DNA of cancer cell line samples.
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:Lymph node involvement is a major prognostic variable in breast cancer. Whether the molecular mechanisms that drive breast cancer cells to colonize lymph nodes are shared with their capacity to form distant metastases is yet to be established. In a transcriptomic survey aimed at identifying molecular factors associated with lymph node involvement of ductal breast cancer, we found that luminal differentiation, assessed by the expression of estrogen receptor (ER) and/or progesterone receptor (PR) and GATA3, was only infrequently lost in node-positive primary tumors and in matched lymph node metastases. The transcription factor GATA3 critically determines luminal lineage specification of mammary epithelium and is widely considered a tumor and metastasis suppressor in breast cancer. Strong expression of GATA3 and ER in a majority of primary node-positive ductal breast cancer was corroborated by quantitative RT-PCR and immunohistochemistry in the initial sample set, and by immunohistochemistry in an additional set from 167 patients diagnosed of node-negative and positive primary infiltrating ductal breast cancer, including 102 samples from loco-regional lymph node metastases matched to their primary tumors, as well as 37 distant metastases. These observations suggest that loss of luminal differentiation is not a major factor driving the ability of breast cancer cells to colonize regional lymph nodes. The transcriptomic study comprises 16 samples from Lymph node metastasis from infiltrating ductal breast carcinoma, 18 samples from Primary node-positive infiltrating ductal,7 samples from Primary node-negative infiltrating ductal and 3 samples from Unaffected lymph node were included. Their RNA was isolated and prepared for hybridization to human Affymetrix GeneChip arrays.
Project description:Gene expression profiling of whole tumor tissues consists of a heterogeneous population of tumor and stromal cells. We performed gene expression profiling of flow cytometry purified tumor cells from primary breast tumor tissues and metastatic lymph nodes in order to segregate tumor signatures from stromal signatures. The goal of this set of expression profiles was to understand the underlying mechanism of lymph node metastatic processes by comparing primary breast tumor cell gene expression profiles with that of lymph node metastatic tumor cells. Keywords: breast cancer, lymph node metastasis
Project description:To identify the mRNAs, long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs) involved in the pathogenesis of breast cancer, we performed the whole transcriptome sequencing. The whole transcriptome sequencing was performed with three breast cancer tissues with or without lymph node metastasis in each group, respectively. The results showed that 728 mRNAs, 131 lncRNAs, and 144 circRNAs were differentially expressed in lymph node metastasis group and no lymph node metastasis group (fold change≥2, p<0.05). These data indicate that dysregulation of mRNAs, lncRNAs, and circRNAs may contribute to breast cancer progression.
Project description:To obtain more information about the lymph node metastasis of breast cancer cells, we selected the matched primary breast cancer (PC) and 2 lymph nodes (LN) of 5 patients to perform integrated analysis. The PC, LN samples were analysed with single-cell RNA sequencing.
Project description:To obtain more information about the lymph node metastasis of breast cancer cells, we selected the matched primary breast cancer (PC), positive lymph nodes (PL), and negative lymph nodes (NL) of the same patient to perform integrated analysis. The PC, PL, NL samples were analysed with single-cell RNA sequencing.