Project description:MicroRNA microarray analysis was performed to compare microRNA levels in bone marrow from 4 breast cancer patients with recurrent disease and 4 patients without recurrence. To achieve this goal, we used microRNA microarray analysis to compare microRNA expression in bone marrow from breast cancer patients with and without disease recurrence.
Project description:MicroRNA microarray analysis was performed to compare microRNA levels in bone marrow from 4 breast cancer patients with recurrent disease and 4 patients without recurrence.
Project description:Adjuvant tamoxifen is a valid treatment option for women with estrogen receptor (ER)-positive breast cancer. However, up to 40% of patients experience distant or local recurrence or die. MicroRNAs have been suggested to be important prognosticators in breast cancer. This study aims to identify microRNAs with the potential to predict tamoxifen response. We performed a global microRNA screen in primary tumours of six matched pairs of postmenopausal, ER-positive breast cancer patients treated with tamoxifen, who were either recurrence free or had developed a recurrence. Patients were treated at the Robert Bosch Hospital, Stuttgart, Germany, between 1986 and 2005. Total RNA from FFPE tissue from 12 postmenopausal patients with ER-positive breast cancer (6 patients with and 6 patients without recurrence) was extracted. Hybridisation of biotin-labelled RNA was performed on Affymetrix GeneChip miRNA_2.0 Arrays.
Project description:Patients with estrogen-receptor-positive (ER+) breast cancer, the most common subtype, remain at risk for lethal metastatic disease years after diagnosis. Recurrence arises partly because tumor cells in bone marrow become resistant to estrogen-targeted therapy. Here, we utilized a co-culture model of bone marrow mesenchymal stem cells (MSCs) and ER+ breast cancer cells to recapitulate interactions of cancer cells in bone marrow niches. ER+ breast cancer cells in direct contact with MSCs acquire cancer stem-like (CSC) phenotypes with increased resistance to standard antiestrogenic drugs. We confirmed that co-culture with MSCs increased labile iron in breast cancer cells, a phenotype associated with CSCs and disease progression. Clinically approved iron chelators and in-house lysosomal iron-targeting compounds restored sensitivity to antiestrogenic therapy. These findings establish iron modulation as a mechanism to reverse MSC-induced drug resistance and suggest iron modulation in combination with estrogen-targeted therapy as a promising, translatable strategy to treat ER+ breast cancer.
Project description:Adjuvant tamoxifen is a valid treatment option for women with estrogen receptor (ER)-positive breast cancer. However, up to 40% of patients experience distant or local recurrence or die. MicroRNAs have been suggested to be important prognosticators in breast cancer. This study aims to identify microRNAs with the potential to predict tamoxifen response. We performed a global microRNA screen in primary tumours of six matched pairs of postmenopausal, ER-positive breast cancer patients treated with tamoxifen, who were either recurrence free or had developed a recurrence. Patients were treated at the Robert Bosch Hospital, Stuttgart, Germany, between 1986 and 2005.
Project description:Using microarray-based technology, we have performed a microRNA expression analysis in 75 primary breast tumors from patients that either remained disease-free at 5 years post-surgery (group A) or developed early (group B) or late (group C) recurrence after surgical removal of the tumor and we have have identified a set of recurrence-related microRNAs with potential prognostic value to identify patients who will likely develop metastasis early after primary breast surgery.
Project description:Breast cancer patients have increased risk of myocardial infarction (MI), but whether these events impact cancer pathogenesis is not known. In mouse models of breast cancer, MI increased circulating Ly6Chigh monocytes and their recruitment to tumors, accelerating cancer progression and metastasis. Analysis of the bone marrow reservoir revealed that MI epigenetically reprogrammed Ly6Chigh monocytes to an immunosuppressive phenotype that was maintained in monocytes in the circulation and tumor at the transcriptional level. Depletion of Ly6Chigh monocytes abrogated MI-induced cancer progression and increased activated cytotoxic T cells in the tumor. In early-stage breast cancer patients, post-diagnosis incident cardiovascular events, such as MI, increased the risk of recurrence and cancer-specific mortality, highlighting the clinical relevance of our findings. Collectively, our results indicate that MI induces cross-disease communication that accelerates breast cancer progression.
