Radiotherapy is widely used to treat human cancer. Patients locally recurring after radiotherapy, however, have increased risk of metastatic progression and poor prognosis. The clinical management of post-radiation recurrences remains an unresolved issue. Tumors growing in pre-irradiated tissues have an increased fraction of hypoxic cells and are more metastatic, a condition known as tumor bed effect. Here we demonstrate that tumor cells growing in a pre-irradiated bed, or selected in vitro though repeated cycles of severe hypoxia, retain an invasive and metastatic capacities when returned to normoxia. HIF activity, while it facilitates metastatic spreading of tumors growing in a pre-irradiated bed, is not essential. Through gene expression profiling and gain and loss of function experiments, we identified the matricellular protein CYR61 and aVb5 integrin, as proteins cooperating to mediate these effects. Inhibition of aVb5 integrin suppressed invasion and metastasis induced by CYR61 and attenuated metastasis of tumors growing within a pre-irradiated field. These results represent a conceptual advance to the understanding of the tumor bed effect and identify CYR61 and aVb5 integrin as proteins that co-operate to mediate metastasis. They also indicate aV integrin inhibition a potential therapeutic approach for preventing metastasis in patients at risk for post-radiation recurrences, which can be promptly tested in the clinic.
CYR61 and alphaVbeta5 integrin cooperate to promote invasion and metastasis of tumors growing in preirradiated stroma.
No sample metadata fields
View SamplesDespite advances in surgery and radiotherapy of uveal melanoma (UM), many patients develop distant metastases that poorly respond to therapy. Improved therapies for the metastatic disease are therefore urgently needed. Expression of the epidermal growth factor receptor (EGFR), a target of kinase inhibitors and humanized antibodies in use for several cancers, had been reported. 48 human UMs were analyzed by expression profiling. Evidence for signaling in tumors was obtained through the application of a UM-specific EGF signature. The EGFR specific kinase inhibitor, Gefitinib, and the humanized monoclonal antibody, Cetuximab, were tested for their effect on EGFR signaling. Natural killer cell mediated antibody-dependent cellular cytotoxicity (ADCC) and TNF-alpha release was analyzed for Cetuximab. EGFR appears suited as a novel molecular drug target for therapy of uveal melanoma.
Evidence of epidermal growth factor receptor expression in uveal melanoma: inhibition of epidermal growth factor-mediated signalling by Gefitinib and Cetuximab triggered antibody-dependent cellular cytotoxicity.
Sex, Specimen part, Disease, Disease stage
View SamplesThe glycopeptide antibiotic vancomycin (VCM) represents one of the last lines of defense against methicillin-resistant Staphylococcus aureus infections. However, vancomycin is nephrotoxic, but the mechanism of toxicity is still unclear.
Gene expression analysis reveals new possible mechanisms of vancomycin-induced nephrotoxicity and identifies gene markers candidates.
Specimen part
View SamplesUveal melanoma is an aggressive cancer that metastasizes to the liver in about half of patients, being at that time almost always fatal. Identification of patients at high risk of metastases may provide indication for a frequent follow-up for early detection of metastases and treatment. The analysis of the gene expression profiling of primary human uveal melanomas showed high expression of SDCBP (encoding for syndecan-binding protein-1 or syntenin-1), which appeared higher in patients with recurrence, whereas expression of syndecans was lower and unrelated to progression. Moreover, we found that high expression of SDCBP gene was related to metastatic progression in two additional independent dataset of uveal melanoma patients. More importantly, immunohistochemistry showed that high expression of syntenin-1 protein in primary tumours was significantly related to metastatic recurrence in our cohort of patients. Syntenin-1 expression was confirmed by RT-PCR, immunofluorescence and immunohistochemistry in cultured uveal melanoma cells or primary tumours. A pseudo-metastatic model of uveal melanoma to the liver was developed in NOD/SCID/IL2R null mice and the study of syntenin-1 expression in primary and metastatic lesions revealed higher syntenin-1 expression in metastases. The inhibition of SDCBP expression by siRNA impaired the ability of uveal melanoma cells to migrate in a woundhealing assay. These results suggest that SDCBP is involved in uveal melanoma progression and that it represents a candidate molecular marker of metastases and a potential therapeutic target.
Mda-9/syntenin is expressed in uveal melanoma and correlates with metastatic progression.
Sex, Specimen part
View SamplesSpinal inhibitory interneurons play crucial roles in shaping motor output, but the molecular heterogeneity contained within cardinal spinal interneuron populations is unclear.
Spinal Inhibitory Interneuron Diversity Delineates Variant Motor Microcircuits.
Specimen part
View SamplesWe used microarrays to detail the global programme of gene expression after knockdown of Ecdysoneless in hMECs
The cell cycle regulator ecdysoneless cooperates with H-Ras to promote oncogenic transformation of human mammary epithelial cells.
Specimen part, Cell line
View SamplesBreast cancers with HER2 overexpression are sensitive to drugs targeting the receptor or its kinase activity. HER2-targeting drugs are initially effective against HER2- positive breast cancer, but resistance inevitably occurs. We previously found that nuclear factor kappa B is hyper-activated in the subset of HER-2 positive breast cancer cells and tissue specimens. In this study, we report that constitutively active NF-B rendered HER2-positive cancer cells resistant to anti-HER2 drugs, and cells selected for Lapatinib resistance up-regulated NF-B. In both circumstances, cells were anti-apoptotic and grew rapidly as xenografts. Lapatinib-resistant cells were refractory to HER2 and NF-B inhibitors alone but were sensitive to their combination, suggesting a novel therapeutic strategy. A subset of NF-B-responsive genes was overexpressed in HER2-positive and triple-negative breast cancers, and patients with this NF-B signature had poor clinical outcome. Anti-HER2 drug resistance may be a consequence of NF-B activation, and selection for resistance results in NF-B activation, suggesting this transcription factor is central to oncogenesis and drug resistance. Clinically, the combined targeting of HER2 and NF-B suggests a potential treatment paradigm for patients who relapse after anti-HER2 therapy. Patients with these cancers may be treated by simultaneously suppressing HER2 signaling and NF-B activation.
NF-κB activation-induced anti-apoptosis renders HER2-positive cells drug resistant and accelerates tumor growth.
Specimen part
View SamplesJoint injury and osteoarthritis affect millions of people worldwide, but attempts to generate articular cartilage using adult stem/progenitor cells have been unsuccessful. We hypothesized that recapitulation of the human developmental chondrogenic program using pluripotent stem cells (PSCs) may represent a superior approach for cartilage restoration. Using laser capture microdissection followed by microarray analysis, we first defined a surface phenotype (CD146low/negCD166low/negCD73+CD44lowBMPR1B+) distinguishing the earliest cartilage committed cells (pre-chondrocytes) at 5-6 weeks of development; pellet assays confirmed these cells as functional, chondrocyte-restricted progenitors. Flow cytometry, qPCR and immunohistochemistry at 17 weeks revealed that the superficial layer of peri-articular chondrocytes was enriched in cells with this surface phenotype. Isolation of cells with a similar immunophenotype from differentiating human PSCs revealed a population of CD166negBMPR1B+ putative pre-chondrocytes. Functional characterization confirmed these cells as cartilage-committed, chondrocyte progenitors. The identification of a specific molecular signature for primary cartilagecommitted progenitors may provide essential knowledge for the generation of purified, clinically relevant cartilage cells from PSCs.
Human developmental chondrogenesis as a basis for engineering chondrocytes from pluripotent stem cells.
No sample metadata fields
View SamplesPrimary T cell activation involves the integration of three distinct signals delivered in sequence: 1) antigen recognition, 2) costimulation, and 3) cytokine-mediated differentiation and expansion. Strong immunostimulatory events such as immunotherapy or infection induce profound cytokine release causing bystander T cell activation, thereby increasing the potential for autoreactivity and need for control. We show that during strong stimulation, a profound suppression of primary CD4+ T cell-mediated immune responses ensued and was observed across preclinical models and patients undergoing high-dose interleukin-2 (IL-2) therapy. This suppression targeted nave CD4+ but not CD8+ T cells and was mediated through transient suppressor of cytokine signaling-3 (SOCS3) inhibition of the STAT5b transcription factor signaling pathway. These events resulted in complete paralysis of primary CD4+ T cell activation affecting memory generation, induction of autoimmunity, as well as impaired viral clearance. These data highlight the critical regulation of nave CD4+ T cells during inflammatory conditions.
Out-of-Sequence Signal 3 Paralyzes Primary CD4(+) T-Cell-Dependent Immunity.
Treatment
View SamplesThis SuperSeries is composed of the SubSeries listed below.
S-adenosylmethionine levels regulate the schwann cell DNA methylome.
Specimen part, Treatment
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