Project description:The microenvironment drives mammary gland development and function, and may influence significantly both malignant behavior and cell growth of mammary cancer cells. By restoring context, and forcing cells to properly interpret native signals from the microenvironment, the cancer cell aberrant behavior can be quelled, and organization re-established. In order to restore functional and morphological differentiation, human mammary MCF-7 and MDA-MB-231 cancer cells were allowed to grow in a culture medium filled with a 10% of the albumen (EW, Egg White) from unfertilized chicken egg. That unique microenvironment behaves akin a 3D culture and induces MCF-7 cells to produce acini and branching duct-like structures, distinctive of mammary gland differentiation. EW-treated MDA-MB-231 cells developed buds of acini and duct-like structures. Both MCF-7 and MDA-MB-231 cells produced β-casein, a key milk component. Furthermore, E-cadherin expression was reactivated in MDA-MB-231 cells, as a consequence of the increased cdh1 expression; meanwhile β-catenin - a key cytoskeleton component - was displaced behind the inner cell membrane. Such modification hinders the epithelial-mesenchymal transition in MDA-MB-231 cells. This differentiating pathway is supported by the contemporary down-regulation of canonical pluripotency markers (Klf4, Nanog). Given that egg-conditioned medium behaves as a 3D-medium, it is likely that cancer phenotype reversion could be ascribed to the changed interactions between cells and their microenvironment.
Project description:The tumor microenvironment (TME) is reprogrammed by cancer cells and participates in all stages of tumor progression. The contribution of stromal cells to the reprogramming of the TME is not well understood. Here, we provide evidence of the role of the cytokine oncostatin M (OSM) as central node for multicellular interactions between immune and nonimmune stromal cells and the epithelial cancer cell compartment. OSM receptor (OSMR) deletion in a multistage breast cancer model halted tumor progression. We ascribed causality to the stromal function of the OSM axis by demonstrating reduced tumor burden of syngeneic tumors implanted in mice lacking OSMR. Single-cell and bioinformatic analysis of murine and human breast tumors revealed that OSM expression was restricted to myeloid cells, whereas OSMR was detected predominantly in fibroblasts and, to a lower extent, cancer cells. Myeloid-derived OSM reprogrammed fibroblasts to a more contractile and tumorigenic phenotype and elicited the secretion of VEGF and proinflammatory chemokines CXCL1 and CXCL16, leading to increased myeloid cell recruitment. Collectively, our data support the notion that the stromal OSM/OSMR axis reprograms the immune and nonimmune microenvironment and plays a key role in breast cancer progression.
Project description:Increased expression of the invasion- and metastasis-associated protein S100A4 is found in many types of cancer, but the regulation of S100A4 expression is poorly understood. The microenvironment surrounding tumors has a significant effect on tumor progression, and in the present study, we investigated the role of the microenvironment in the expression of S100A4. Tumors of three different human carcinoma cell lines were established in the tongue or skin of mice, and S100A4 expression was assessed by quantitative RT-PCR, Western blotting, and immunohistochemical analysis in tumors and stromal tissue and in cancer cells grown in vitro. Tongue tumors of the oral squamous cell carcinoma cell line HSC-4 showed a pronounced increase in S100A4 expression during tumor growth, whereas only a minor increase was detected in skin tumors of the same cell line. The S100A4 expression correlated with the methylation status of cytosine-guanine sites in the first intron of the gene. For all cell lines, S100A4 expression in the tumor stroma was related to the presence of inflammatory cells rather than to the level of S100A4 in the tumor cells.
Project description:Introduction: Amplification at chromosome 8q24 is one of the most frequent genomic abnormalities in human cancers and is associated with reduced survival duration in breast and ovarian cancers. The minimal amplified region encodes c-MYC and the non-coding RNA, PVT1 including miR-1204 encoded in exon 1b. Here we analyzed the genomic changes at chromosome 8q24.21 in breast cancer and the functional roles of miR-1204 in breast and ovarian cancer progression. Methods: The genomic changes at chromosome 8q24.21 were detected in 997 breast cancer tumors and 40 breast cancer cell lines. Expression of miR-1204 in breast and ovarian cancer cell lines was investigated by qRT-PCR method. The role of miR-1204 in the tumorigenesis of breast and ovarian cancer was explored using both knockdown and overexpression of miR-1204 in vitro. Candidate miR-1204 target genes from two independent expression microarray datasets and computational predict programs were identified and further validated by qRT-PCR and western blot methods. The role of inhibition of miR-1204 on tamoxifen sensitivity in breast cancer cells was also investigated. Results: MiR-1204 is frequently co-amplified with MYC and expression of miR-1204 is strongly correlated with the expression and amplification of the noncoding PVT1 transcript and less so with MYC in human breast and ovarian cancer cells. Inhibition of miR-1204 decreases cell proliferation and increased apoptosis in breast and ovarian cancer cell lines with 8q24 amplification, but not in lines without amplification and so may be involved in Myc-induced apoptosis. Additionally, overexpression of miR-1204 enhances both breast and ovarian cancer cell growth and Myc-initiated Rat1A cell transformation. Computational and experimental analyses 30 promising candidate miR-1204 target genes. mRNA levels for these genes were assessed after over expression and knockdown of miR-1204 as were protein levels for 10 genes for which antibodies were available. These studies implicated VDR and ESR1 as miR-1204 targets. Inhibition of miR-1204 increased response to tamoxifen in Estrogen Receptor negative breast cancer cell lines. Conclusions: We conclude that amplification of miR-1204 contributes to breast and ovarian pathophysiology at least in part, by increasing proliferation and down regulating apoptosis and by decreasing expression of VDR and ESR1. Seven cell line sample pairs, where samples are LNA transfected with antimiR-1204 or antimiR-1204 control
Project description:BackgroundIn order to facilitate the identification of genes involved in the metastatic phenotype we have previously developed a pair of cell lines from the human breast carcinoma cell line MDA-MB-435, which have diametrically opposite metastatic potential in athymic mice. Differential display analysis of this model previously identified a novel gene, DRIM (down regulated in metastasis), the decreased expression of which correlated with metastatic capability. DRIM encodes a protein comprising 2785 amino acids with significant homology to a protein in yeast and C. elegans, but little else is currently known about its function or pattern of expression. In a detailed analysis of the DRIM gene locus we quantitatively evaluated gene dosage and the expression of DRIM transcripts in a panel of breast cell lines of known metastatic phenotype.ResultsFluorescent in situ hybridization (FISH) analyses mapped a single DRIM gene locus to human chromosome 12q23~24, a region of conserved synteny to mouse chromosome 10. We confirmed higher expression of DRIM mRNA in the non-metastatic MDA-MB-435 clone NM2C5, relative to its metastatic counterpart M4A4, but this appeared to be due to the presence of an extra copy of the DRIM gene in the cell line's genome. The other non-metastatic cell lines in the series (T47D MCF-7, SK-BR-3 and ZR-75-1) contained either 3 or 4 chromosomal copies of DRIM gene. However, the expression level of DRIM mRNA in M4A4 was found to be 2-4 fold higher than in unrelated breast cells of non-metastatic phenotype.ConclusionsWhilst DRIM expression is decreased in metastatic M4A4 cells relative to its non-metastatic isogenic counterpart, neither DRIM gene dosage nor DRIM mRNA levels correlated with metastatic propensity in a series of human breast tumor cell lines examined. Collectively, these findings indicate that the expression pattern of the DRIM gene in relation to the pathogenesis of breast tumor metastasis is more complex than previously recognized.
Project description:Extracellular matrix (ECM) is an essential and dynamic component of all tissues and directly affects cellular behavior by providing both mechanical and biochemical signaling cues. Changes in ECM can alter tissue homeostasis, potentially leading to promotion of cellular transformation and the generation of tumors. Therefore, understanding ECM compositional changes during cancer progression is vital to the development of targeted treatments. Previous efforts to reproduce the native 3D cellular microenvironment have utilized protein gels and scaffolds that incompletely recapitulate the complexity of native tissues. Here, we address this problem by extracting and comparing ECM from normal human colon and colon tumor that had metastasized to liver. We found differences in protein composition and stiffness, and observed significant differences in vascular network formation and tumor growth in each of the reconstituted matrices, both in vitro and in vivo. We studied free/bound ratios of NADH in the tumor and endothelial cells using Fluorescence Lifetime Imaging Microscopy as a surrogate for the metabolic state of the cells. We observed that cells seeded in tumor ECM had higher relative levels of free NADH, consistent with a higher glycolytic rate, than those seeded in normal ECM. These results demonstrate that the ECM plays an important role in the growth of cancer cells and their associated vasculature.
Project description:BackgroundSince the first evidence suggesting existence of stem-like cancer cells, the process of cells reprogramming to the stem cell state remains as an attractive tool for cancer stemness research. Current knowledge in the field of cancer stemness, indicates that the microenvironment is a fundamental regulator of cell behavior. With regard to this, we investigated the changes of genome wide gene expression in reprogrammed human colon normal epithelial CRL-1831 and colon carcinoma DLD1 cell lines grown under more physiologically relevant three-dimensional (3D) cell culture microenvironment compared to 2D monolayer.MethodsWhole genome gene expression changes were evaluated in both cell lines cultured under 3D conditions over a 2D monolayer by gene expression microarray analysis. To evaluate the biological significance of gene expression changes, we performed pathway enrichment analysis using the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. Gene network analysis was used to study relationships between differentially expressed genes (DEGs) in functional categories by the GeneMANIA Cytoscape toolkit.ResultsIn total, we identified 3228 and 2654 differentially expressed genes (DEGs) for colon normal and cancer reprogrammed cell lines, respectively. Furthermore, the expression of 1097 genes was commonly regulated in both cell lines. KEGG enrichment analysis revealed that in total 129 and 101 pathways for iPSC-CRL-1831 and for CSC-DLD1, respectively, were enriched. Next, we grouped these pathways into three functional categories: cancer transformation/metastasis, cell interaction, and stemness. β-catenin (CTNNB1) was confirmed as a hub gene of all three functional categories.ConclusionsOur present findings suggest common pathways between reprogrammed human colon normal epithelium (iPSC-CRL-1831) and adenocarcinoma (CSC-DLD1) cells grown under 3D microenvironment. In addition, we demonstrated that pathways important for cancer transformation and tumor metastatic activity are altered both in normal and cancer stem-like cells during the transfer from 2D to 3D culture conditions. Thus, we indicate the potential of cell culture models enriched in normal and cancer stem-like cells for the identification of new therapeutic targets in cancer treatment.
Project description:The tumor microenvironment (TME) is an important mediator of breast cancer progression. Cancer-associated fibroblasts constitute a major component of the TME and may originate from tissue-associated fibroblasts or infiltrating mesenchymal stromal cells (MSCs). The mechanisms by which cancer cells activate fibroblasts and recruit MSCs to the TME are largely unknown, but likely include deposition of a pro-tumorigenic secretome. The secreted embryonic protein NODAL is clinically associated with breast cancer stage and promotes tumor growth, metastasis, and vascularization. Herein, we show that NODAL expression correlates with the presence of activated fibroblasts in human triple-negative breast cancers and that it directly induces Cancer-associated fibroblasts phenotypes. We further show that NODAL reprograms cancer cell secretomes by simultaneously altering levels of chemokines (e.g., CXCL1), cytokines (e.g., IL-6) and growth factors (e.g., PDGFRA), leading to alterations in MSC chemotaxis. We therefore demonstrate a hitherto unappreciated mechanism underlying the dynamic regulation of the TME.