Project description:Patients diagnosed with estrogen receptor (ER) positive breast cancer have a prolonged risk of distal metastatic recurrence to vital organs. Metastatic disease is incurable at present due to the development of treatment resistant cell populations. Here we used single-cell RNA sequencing to evaluate the transcriptome heterogeneity of ER+ breast cancer patient-derived xenografts (PDX) tropic for three common breast cancer metastatic sites – bone, brain, and liver – compared to primary tumors grown in the mammary fat pad. Metastatic cell populations at each location were phenotypically distinct from primary tumor cells with unique transcriptional programs indicative of signaling programs driven by specific transcription factors. Cells that metastasized to brain and liver tissue adopted gene expression programs indicative of the target organ microenvironments. Discerning the organ-specific phenotypic adaptations of metastatic ER+ breast cancer cells may help tailor appropriate therapies for individual patients and to each metastatic site.
Project description:We report that the cell of origin plays an important role in this metastatic tropism. Following injection into the arterial circulation of mice, each of the identically transformed cell types gave rise to different metastatic patterns. Using gene expression analysis, we identified the chemokine receptor CXCR4 as being instrumental in determining the distinct metastatic patterns between skeletal muscle precursor cells and skeletal myoblasts.
Project description:We report that the cell of origin plays an important role in this metastatic tropism. Following injection into the arterial circulation of mice, each of the identically transformed cell types gave rise to different metastatic patterns. Using gene expression analysis, we identified the chemokine receptor CXCR4 as being instrumental in determining the distinct metastatic patterns between skeletal muscle precursor cells and skeletal myoblasts. 3 independent cell lines of primary human skeletal myoblasts, primary skeletal muscle cell precursors, and each of these cell lines transformed with hTERT, the early region of SV40 encoding T-Ag and t-Ag, and RasG12V analysis of primary human skeletal myoblasts, primary skeletal muscle cell precursors, and each of these cell lines transformed with hTERT, the early region of SV40 encoding T-Ag and t-Ag, and RasG12V
Project description:Hormones and growth factors accelerate cell proliferation of breast cancer cells, and these molecules are well investigated targets for drug development and application. The mechanisms of cell proliferation of breast cancers lacking estrogen receptor (ER) and HER2 have not been fully understood. The purpose of the present study is to find genes that are differentially expressed in breast cancers and that might significantly contribute to cell proliferation in these cancers. Forty tumor samples, consisting of ten each of immunohistochemically ER(+)/HER2(-), ER(+)/HER2(+), ER(-)/HER2(+), and ER(-)/HER2(-) cancer were analyzed using oligonucleotide microarrays. Both genes and tumor samples were subjected to hierarchical clustering. ER(+)/HER2(-) breast cancers and ER(-)/HER2(-) cancers tended to form a tumor cluster, but HER2 positive breast cancers were split into different tumor clusters. Significant differential expression between IHC-ER(-)/HER2(-) and other tumors was defined as having an expression level at least 2-fold higher or 2-fold lower, and analyzed by multi-step two-way ANOVA. Genes overexpressed differently in IHC-ER(-)/HER2(-) breast cancers compared to other all three types were 8 genes (FABP7, GABRP, GAL, CXCL13, CDC42EP4, C2F, FOXM1, CSDA), and underexpressed genes were nine including ITGB5, KIAA0310, MAGED2, PRSS11, SORL1, TGFB3, KRT18, CPE, BCAS1. No gene was directly related to cell proliferation such as cyclins, cyclin-dependent kinase, p53, p16, and the pRb and p21 families. We had a particular focus on a transcriptional factor E2F-5 from a list of genes overexpressed in ER negative breast cancers compared to ER positive breast cancers, and further examined. Gene amplification of E2F-5 was detected in 5/57 (8.8%) in breast cancers by FISH. No point mutation was found at the binding domain with DNA or dimerization partner of E2F-5. Immunohistochemically E2F-5 positive cancers were more frequent in ER(-)/HER2(-) cancer (14/27, 51.9%) than in other types of cancer (5/30, 16.7%) (p=0.05). E2F-5 positive cancers had higher Ki-67 labeling index (59.5%) than E2F-5 negative cancers (36.3%). E2F-5 positive cancers showed higher histological grade including metaplastic carcinoma, and worse clinical outcome with shorter disease free survival in node negative patients. In conclusion, we demonstrated that there is a population of breast cancer with overexpression of a cell cycle related transcriptional factor E2F-5. E2F-5 positive breast cancers were frequent in ER(-)/HER2(-) group with high Ki-67 labeling index, high histological grade and worse clinical outcome. Keywords: immunohistochemical phenotype
Project description:Cancer cells adapt to signals in the tumor microenvironment (TME), but the TME cues that impact metastasis and tropism are unknown. We show that stromal lipids from young adipocytes are taken up by melanoma cells, and lipids increase melanoma oxidative phosphorylation (OXPHOS) and oxidative stress, which decreases metastatic burden. In contrast, the aged TME provides fewer lipids, leading to lower OXPHOS and higher metastatic capacity. Young adipocytes transfer phosphatidylcholine (PC) to melanoma cells, where PC upregulates PI3K/AKT and mitochondrial OXPHOS. Melanoma cells with high OXPHOS predominantly seed the lung and brain, but do not colonise the liver, and decreasing oxidative stress with antioxidant supplements shifts tropism from the lung to the liver. In contrast, although the aged stroma has fewer total lipids, it has more ceramides, which activate the S1P/STAT3/IL6 signalling axis to direct melanoma liver tropism. Inhibiting OXPHOS in the young stroma and blocking IL6 receptor in the aged stroma reduces the age-specific patterns of metastasis imposed by stromal lipids.
Project description:Cancer cells adapt to signals in the tumor microenvironment (TME), but the TME cues that impact metastasis and tropism are unknown. We show that stromal lipids from young adipocytes are taken up by melanoma cells, and lipids increase melanoma oxidative phosphorylation (OXPHOS) and oxidative stress, which decreases metastatic burden. In contrast, the aged TME provides fewer lipids, leading to lower OXPHOS and higher metastatic capacity. Young adipocytes transfer phosphatidylcholine (PC) to melanoma cells, where PC upregulates PI3K/AKT and mitochondrial OXPHOS. Melanoma cells with high OXPHOS predominantly seed the lung and brain, but do not colonise the liver, and decreasing oxidative stress with antioxidant supplements shifts tropism from the lung to the liver. In contrast, although the aged stroma has fewer total lipids, it has more ceramides, which activate the S1P/STAT3/IL6 signalling axis to direct melanoma liver tropism. Inhibiting OXPHOS in the young stroma and blocking IL6 receptor in the aged stroma reduces the age-specific patterns of metastasis imposed by stromal lipids.
Project description:Cancer cells adapt to signals in the tumor microenvironment (TME), but the TME cues that impact metastasis and tropism are unknown. We show that stromal lipids from young adipocytes are taken up by melanoma cells, and lipids increase melanoma oxidative phosphorylation (OXPHOS) and oxidative stress, which decreases metastatic burden. In contrast, the aged TME provides fewer lipids, leading to lower OXPHOS and higher metastatic capacity. Young adipocytes transfer phosphatidylcholine (PC) to melanoma cells, where PC upregulates PI3K/AKT and mitochondrial OXPHOS. Melanoma cells with high OXPHOS predominantly seed the lung and brain, but do not colonise the liver, and decreasing oxidative stress with antioxidant supplements shifts tropism from the lung to the liver. In contrast, although the aged stroma has fewer total lipids, it has more ceramides, which activate the S1P/STAT3/IL6 signalling axis to direct melanoma liver tropism. Inhibiting OXPHOS in the young stroma and blocking IL6 receptor in the aged stroma reduces the age-specific patterns of metastasis imposed by stromal lipids.