Project description:Background MicroRNA expression is frequently dysregulated in cancer and it could be used potentially as a disease classifier and a prognostic tool in cancer. It has been reported that the cancer associated specific microRNAs were stably detected in blood. The objective of this study was to discover a panel of circulating microRNAs as potential ER+/HER2- breast cancer biomarkers. Methods We compared levels of circulating microRNAs in blood samples from 11 ER+/HER2- advanced breast cancer patients with age-matched 5 control subjects by using microarray-based expression profiling. We validated the level of microRNAs by real-time quantitative polymerase cycle reaction (RT-qPCR) in 40 control subjects, 180 early breast cancer patients (EBC), and 52 metastatic breast cancer patients (MBC). Then, we assessed the association between the levels of microRNA and clinical outcomes of ER+/HER2- metastatic breast cancer. Background MicroRNA expression is frequently dysregulated in cancer and it could be used potentially as a disease classifier and a prognostic tool in cancer. It has been reported that the cancer associated specific microRNAs were stably detected in blood. The objective of this study was to discover a panel of circulating microRNAs as potential ER+/HER2- breast cancer biomarkers. Methods We compared levels of circulating microRNAs in blood samples from 11 ER+/HER2- advanced breast cancer patients with age-matched 5 control subjects by using microarray-based expression profiling. We validated the level of microRNAs by real-time quantitative polymerase cycle reaction (RT-qPCR) in 40 control subjects, 180 early breast cancer patients (EBC), and 52 metastatic breast cancer patients (MBC). Then, we assessed the association between the levels of microRNA and clinical outcomes of ER+/HER2- metastatic breast cancer. Controls: 5 cases; ER +/HER2- breast cancer patients : 11 cases
Project description:This is a quality control (QC) substudy of GSE48091. The QC substudy comprises gene-expression profiling of re-extracted tumor RNA for a subset of the tumours in the full study. As background, a population-based cohort study of metastatic breast cancer patients was first designed. Thereafter, a case-control study nested in the corresponding population-based cohort of primary breast cancer patients was designed by selecting distant metastasis-free controls to each case. Tumor RNA was extracted in the same order. All RNA was profiled on microarrays in randomized order. For quality control, RNA was also re-extracted (new tumor piece) in a randomized order for randomly selected cases-controls sets and profiled with the rest. Keywords: Expression profiling by array
Project description:Tumor-host interactions extend beyond the local microenvironment and cancer development largely depends on the ability of malignant cells to hijack and exploit the normal physiological processes of the host. Although abnormalities in a host’s systemic immunity are associated with increased cancer susceptibility, the functional interplay between tumor cells and circulating immune cells in regulating tumorigenic responses is unclear. We employed the Norwegian Women and Cancer study, a large prospective population-based cohort study, to identify gene expression changes in blood cells that provide a robust and reproducible diagnostic signal specific to breast cancer patients. We further show that circulating blood cells in breast cancer patients are enriched in genes involved in systemic immunosuppression and the motility, metabolism, growth, and proliferation of immune cells. By mining of the cancer-associated blood transcriptome, we identified immune mediators or biomarkers that could permit early detection of breast cancer and open avenues to novel targeted immunotherapies.
Project description:Bilaterality of breast cancer is an indicator of constitutional cancer susceptibility, however, the molecular causes underlying this predisposition in the majority of cases is not known. We hypothesize that epigenetic misregulation of cancer related genes could partially account for this predisposition. We have performed methylation microarray analysis of peripheral blood DNA from 14 women with bilateral breast cancer compared to 14 unaffected matched controls throughout 17 candidate breast cancer susceptibility genes including BRCA1, BRCA2, CHEK2, ATM, ESR1, SFN, CDKN2A, TP53, GSTP1, CDH1, CDH13, HIC1, PGR, SFRP1, MLH1, RARB and HSD17B4. We show that the majority of methylation variability is associated with intragenic repetitive elements. Detailed validation of the tiled region around ATM was performed by bisulfite modification and pyrosequencing of the same samples and in a second set of peripheral blood DNA from 190 bilateral breast cancer patients compared to 190 controls. We show significant hypermethylation of one intragenic repetitive element in breast cancer cases compared to controls (p=0.0017) with the highest quartile of methylation associated with a three-fold increased risk of breast cancer (OR = 3.20, 95% C.I.=1.78-5.86, p=0.000083). Increased methylation of this locus is associated with lower steady state ATM mRNA level and correlates with age of cancer patients but not controls, suggesting a combined age-phenotype related association. This research demonstrates the potential for gene-body epigenetic misregulation of ATM and other cancer related genes in peripheral blood DNA that may be useful as a novel marker to estimate breast cancer risk. Keywords: Differential Methylation Hybridisation
Project description:Purpose: To infer interactions between circulating breast cancer cells and peripheral mononuclear cells using bioinformatics analysis of single cell RNA-sequencing. Methods: Filter based method for capturing single cells from 7.5mL of blood from patients with breast cancer, followed by single cell RNA-sequencing. Results: Transcriptomes predicted for two CTC populations with distinct expression profiles and interactions with peripheral blood mononuclear cells.