42 research outputs found
The fibroblast Tiam1-osteopontin pathway modulates breast cancer invasion and metastasis
Background
The tumor microenvironment has complex effects in cancer pathophysiology that are not fully understood. Most cancer therapies are directed against malignant cells specifically, leaving pro-malignant signals from the microenvironment unaddressed. Defining specific mechanisms by which the tumor microenvironment contributes to breast cancer metastasis may lead to new therapeutic approaches against advanced breast cancer.
Methods
We use a novel method for manipulating three-dimensional mixed cell co-cultures, along with studies in mouse xenograft models of human breast cancer and a histologic study of human breast cancer samples, to investigate how breast cancer-associated fibroblasts affect the malignant behaviors of breast cancer cells.
Results
Altering fibroblast Tiam1 expression induces changes in invasion, migration, epithelial-mesenchymal transition, and cancer stem cell characteristics in associated breast cancer cells. These changes are both dependent on fibroblast secretion of osteopontin and also long-lasting even after cancer cell dissociation from the fibroblasts, indicating a novel Tiam1-osteopontin pathway in breast cancer-associated fibroblasts. Notably, inhibition of fibroblast osteopontin with low doses of a novel small molecule prevents lung metastasis in a mouse model of human breast cancer metastasis. Moreover, fibroblast expression patterns of Tiam1 and osteopontin in human breast cancers show converse changes correlating with invasion, supporting the hypothesis that this pathway in tumor-associated fibroblasts regulates breast cancer invasiveness in human disease and is thus clinically relevant.
Conclusions
These findings suggest a new therapeutic paradigm for preventing breast cancer metastasis. Pro-malignant signals from the tumor microenvironment with long-lasting effects on associated cancer cells may perpetuate the metastatic potential of developing cancers. Inhibition of these microenvironment signals represents a new therapeutic strategy against cancer metastasis that enables targeting of stromal cells with less genetic plasticity than associated cancer cells and opens new avenues for investigation of novel therapeutic targets and agents.National Institute of General Medical Sciences (U.S.) (GM074825
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Anatomical localization of progenitor cells in human breast tissue reveals enrichment of uncommitted cells within immature lobules
Introduction: Lineage tracing studies in mice have revealed the localization and existence of lineage-restricted mammary epithelial progenitor cells that functionally contribute to expansive growth during puberty and differentiation during pregnancy. However, extensive anatomical differences between mouse and human mammary tissues preclude the direct translation of rodent findings to the human breast. Therefore, here we characterize the mammary progenitor cell hierarchy and identify the anatomic location of progenitor cells within human breast tissues. Methods: Mammary epithelial cells (MECs) were isolated from disease-free reduction mammoplasty tissues and assayed for stem/progenitor activity in vitro and in vivo. MECs were sorted and evaluated for growth on collagen and expression of lineages markers. Breast lobules were microdissected and individually characterized based on lineage markers and steroid receptor expression to identify the anatomic location of progenitor cells. Spanning-tree progression analysis of density-normalized events (SPADE) was used to identify the cellular hierarchy of MECs within lobules from high-dimensional cytometry data. Results: Integrating multiple assays for progenitor activity, we identified the presence of luminal alveolar and basal ductal progenitors. Further, we show that Type I lobules of the human breast were the least mature, demonstrating an unrestricted pattern of expression of luminal and basal lineage markers. Consistent with this, SPADE analysis revealed that immature lobules were enriched for basal progenitor cells, while mature lobules consisted of increased hierarchal complexity of cells within the luminal lineages. Conclusions: These results reveal underlying differences in the human breast epithelial hierarchy and suggest that with increasing glandular maturity, the epithelial hierarchy also becomes more complex. Electronic supplementary material The online version of this article (doi:10.1186/s13058-014-0453-3) contains supplementary material, which is available to authorized users
Cost-Effectiveness of Autologous Hematopoietic Stem Cell Transplantation for Elderly Patients with Multiple Myeloma using the Surveillance, Epidemiology, and End Results–Medicare Database
In the past decade, the number of autologous hematopoietic stem cell transplants (Auto HSCT) for older patients with multiple myeloma (MM) has increased dramatically, as has the cost of transplantation. The cost-effectiveness of this modality in patients over age 65 is unclear. Using the Surveillance, Epidemiology, and End ResultseMedicare database to create a propensity-score matched sample of patients over age 65 between 2000 and 2007, we compared the survival and cost for those who received Auto HSCT to those who did not undergo transplantation but survived at least 6 months after diagnosis, and we calculated an incremental cost-effectiveness ratio (ICER). Two hundred seventy patients underwent transplantation. Median overall survival from diagnosis in those who underwent transplantation was significantly longer than in patients who did not (58 months versus 37 months, P < .001). For patients living longer than 2 years, the median monthly cost during the first year was significantly different, but the middle and last year of life costs were similar. The median cost of the first 100 days after transplantation was 37,000 to 72,852 per life-year gained. Survival after transplantation was comparable to that in those who underwent transplantation patients under 65 years and significantly longer than older patients who did not undergo transplantation. With an ICER less than $100,000/life-year gained, Auto HSCT is cost-effective when compared with nontransplantation care in the era of novel agents and should be considered, where clinically indicated, for patients over the age of 65
Neuroanatomical Pattern of Mitochondrial Complex I Pathology Varies between Schizophrenia, Bipolar Disorder and Major Depression
BACKGROUND:Mitochondrial dysfunction was reported in schizophrenia, bipolar disorderand major depression. The present study investigated whether mitochondrial complex I abnormalities show disease-specific characteristics. METHODOLOGY/PRINCIPAL FINDINGS:mRNA and protein levels of complex I subunits NDUFV1, NDUFV2 and NADUFS1, were assessed in striatal and lateral cerebellar hemisphere postmortem specimens and analyzed together with our previous data from prefrontal and parieto-occipital cortices specimens of patients with schizophrenia, bipolar disorder, major depression and healthy subjects. A disease-specific anatomical pattern in complex I subunits alterations was found. Schizophrenia-specific reductions were observed in the prefrontal cortex and in the striatum. The depressed group showed consistent reductions in all three subunits in the cerebellum. The bipolar group, however, showed increased expression in the parieto-occipital cortex, similar to those observed in schizophrenia, and reductions in the cerebellum, yet less consistent than the depressed group. CONCLUSIONS/SIGNIFICANCE:These results suggest that the neuroanatomical pattern of complex I pathology parallels the diversity and similarities in clinical symptoms of these mental disorders
Cognitive correlates of gray matter abnormalities in adolescent siblings of patients with childhood-onset schizophrenia
Patients with childhood onset schizophrenia (COS) display widespread gray matter (GM) structural brain abnormalities. Healthy siblings of COS patients share some of these structural abnormalities, suggesting that GM abnormalities are endophenotypes for schizophrenia. Another possible endophenotype for schizophrenia that has been relatively unexplored is corticostriatal dysfunction. The corticostriatal system plays an important role in skill learning. Our previous studies have demonstrated corticostriatal dysfunction in COS siblings with a profound skill learning deficit and abnormal pattern of brain activation during skill learning. This study investigated whether structural abnormalities measured using volumetric brain morphometry (VBM) were present in siblings of COS patients and whether these were related to deficits in cognitive skill learning. Results revealed smaller GM volume in COS siblings relative to controls in a number of regions, including occipital, parietal, and subcortical regions including the striatum, and greater GM volume relative to controls in several subcortical regions. Volume in the right superior frontal gyrus and cerebellum were related to performance differences between groups on the weather prediction task, a measure of cognitive skill learning. Our results support the idea that corticostriatal and cerebellar impairment in unaffected siblings of COS patients are behaviorally relevant and may reflect genetic risk for schizophrenia
Breast Cancer-Associated Fibroblasts: Where We Are and Where We Need to Go
Cancers are heterogeneous tissues comprised of multiple components, including tumor cells and microenvironment cells. The tumor microenvironment has a critical role in tumor progression. The tumor microenvironment is comprised of various cell types, including fibroblasts, macrophages and immune cells, as well as extracellular matrix and various cytokines and growth factors. Fibroblasts are the predominant cell type in the tumor microenvironment. However, neither the derivation of tissue-specific cancer-associated fibroblasts nor markers of tissue-specific cancer-associated fibroblasts are well defined. Despite these uncertainties it is increasingly apparent that cancer-associated fibroblasts have a crucial role in tumor progression. In breast cancer, there is evolving evidence showing that breast cancer-associated fibroblasts are actively involved in breast cancer initiation, proliferation, invasion and metastasis. Breast cancer-associated fibroblasts also play a critical role in metabolic reprogramming of the tumor microenvironment and therapy resistance. This review summarizes the current understanding of breast cancer-associated fibroblasts
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Modeling the Costly Rejection of Wrongdoers by Children using a BayesianApproach
In previous work, young children avoided associating with a wrongdoer, despite incurring a personal cost. Such aversionto wrongdoers, arguably a reflection of moral development, weakens when the cost becomes very large (Tasimi & Wynn,2016). We model this moral decision-making process using the nave utility calculus (Jara-Ettinger et al., 2016), assumingutility maximization amidst uncertainty using Bayesian framework. The cost is defined as the number of stickers forgoneby choosing a nice persons smaller offer over a mean persons larger one, following the ratios of 1:2, 1:4, 1:8, and 1:16. Ourmodel aims to explain previous findings, and test predictions for new ratios. Compared to a baseline condition where nobackground information is available, children are predicted to choose the nice person when the cost is low, but reverse theirpreference when the cost becomes increasingly high, which would suggest a utility account for moral decision making