Search results for " Nude"
showing 10 items of 172 documents
NOTCH3 expression is linked to breast cancer seeding and distant metastasis
2018
Background Development of distant metastases involves a complex multistep biological process termed the invasion-metastasis cascade, which includes dissemination of cancer cells from the primary tumor to secondary organs. NOTCH developmental signaling plays a critical role in promoting epithelial-to-mesenchymal transition, tumor stemness, and metastasis. Although all four NOTCH receptors show oncogenic properties, the unique role of each of these receptors in the sequential stepwise events that typify the invasion-metastasis cascade remains elusive. Methods We have established metastatic xenografts expressing high endogenous levels of NOTCH3 using estrogen receptor alpha-positive (ERα+) MCF…
Stem cell functionality is microenvironmentally defined during tumour expansion and therapy response in colon cancer
2018
Solid malignancies have been speculated to depend on cancer stem cells (CSCs) for expansion and relapse after therapy. Here we report on quantitative analyses of lineage tracing data from primary colon cancer xenograft tissue to assess CSC functionality in a human solid malignancy. The temporally obtained clone size distribution data support a model in which stem cell function in established cancers is not intrinsically, but is entirely spatiotemporally orchestrated. Functional stem cells that drive tumour expansion predominantly reside at the tumour edge, close to cancer-associated fibroblasts. Hence, stem cell properties change in time depending on the cell location. Furthermore, although…
Microparticles harbouring Sonic hedgehog morphogen improve the vasculogenesis capacity of endothelial progenitor cells derived from myocardial infarc…
2019
Aims Endothelial progenitor cells (EPC) play a role in endothelium integrity maintenance and regeneration. Decreased numbers of EPC or their impaired function correlates with an increase in cardiovascular events. Thus, EPC are important predictors of cardiovascular mortality and morbidity. Microparticles carrying Sonic hedgehog (Shh) morphogen (MPShh+) trigger pro-angiogenic responses, both in endothelial cells and in ischaemic rodent models. Here, we propose that MPShh+ regulates EPC function, thus enhancing vasculogenesis, and correcting the defects in dysfunctional EPC obtained from acute myocardial infarction (AMI) patients. Methods and results The mechanisms underlying Shh pathway func…
T cells mediate autoantibody-induced cutaneous inflammation and blistering in epidermolysis bullosa acquisita
2016
AbstractT cells are key players in autoimmune diseases by supporting the production of autoantibodies. However, their contribution to the effector phase of antibody-mediated autoimmune dermatoses, i.e., tissue injury and inflammation of the skin, has not been investigated. In this paper, we demonstrate that T cells amplify the development of autoantibody-induced tissue injury in a prototypical, organ-specific autoimmune disease, namely epidermolysis bullosa acquisita (EBA) – characterized and caused by autoantibodies targeting type VII collagen. Specifically, we show that immune complex (IC)-induced inflammation depends on the presence of T cells – a process facilitated by T cell receptor (…
Apoptosis induced by a HIPK2 full-length-specific siRNA is due to off-target effects rather than prevalence of HIPK2-Δe8 isoform
2017
Small interfering RNAs (siRNAs) are widely used to study gene function and extensively exploited for their potential therapeutic applications. HIPK2 is an evolutionary conserved kinase that binds and phosphorylates several proteins directly or indirectly related to apoptosis. Recently, an alternatively spliced isoform skipping 81 nucleotides of exon 8 (Hipk2-Δe8) has been described. Selective depletion of Hipk2 full-length (Hipk2-FL) with a specific siRNA that spares the Hipk2-Δe8 isoform has been shown to strongly induce apoptosis, suggesting an unpredicted dominant-negative effect of Hipk2-FL over the Δe8 isoform. From this observation, we sought to take advantage and assessed the therape…
MET-EGFR dimerization in lung adenocarcinoma is dependent on EGFR mtations and altered by MET kinase inhibition
2017
Advanced lung cancer has poor survival with few therapies. EGFR tyrosine kinase inhibitors (TKIs) have high response rates in patients with activating EGFR mutations, but acquired resistance is inevitable. Acquisition of the EGFR T790M mutation causes over 50% of resistance; MET amplification is also common. Preclinical data suggest synergy between MET and EGFR inhibitors. We hypothesized that EGFR-MET dimerization determines response to MET inhibition, depending on EGFR mutation status, independently of MET copy number. We tested this hypothesis by generating isogenic cell lines from NCI-H1975 cells, which co-express L858R and T790M EGFR mutations, namely H1975L858R/T790M (EGFR TKI resista…
Autocrine CCL5 Effect Mediates Trastuzumab Resistance by ERK Pathway Activation in HER2-Positive Breast Cancer.
2020
Abstract HER2-positive breast cancer is currently managed with chemotherapy in combination with specific anti-HER2 therapies, including trastuzumab. However, a high percentage of patients with HER2-positive tumors do not respond to trastuzumab (primary resistance) or either recur (acquired resistance), mostly due to molecular alterations in the tumor that are either unknown or undetermined in clinical practice. Those alterations may cause the tumor to be refractory to treatment with trastuzumab, promoting tumor proliferation and metastasis. Using continued exposure of a HER2-positive cell line to trastuzumab, we generated a model of acquired resistance characterized by increased expression …
PTEN status is a crucial determinant of the functional outcome of combined MEK and mTOR inhibition in cancer
2017
AbstractCombined MAPK/PI3K pathway inhibition represents an attractive, albeit toxic, therapeutic strategy in oncology. Since PTEN lies at the intersection of these two pathways, we investigated whether PTEN status determines the functional response to combined pathway inhibition. PTEN (gene, mRNA, and protein) status was extensively characterized in a panel of cancer cell lines and combined MEK/mTOR inhibition displayed highly synergistic pharmacologic interactions almost exclusively in PTEN-loss models. Genetic manipulation of PTEN status confirmed a mechanistic role for PTEN in determining the functional outcome of combined pathway blockade. Proteomic analysis showed greater phosphoprote…
Antibody–Fc/FcR Interaction on Macrophages as a Mechanism for Hyperprogressive Disease in Non–small Cell Lung Cancer Subsequent to PD-1/PD-L1 Blockade
2019
Abstract Purpose: Hyperprogression (HP), a paradoxical boost in tumor growth, was described in a subset of patients treated with immune checkpoint inhibitors (ICI). Neither clinicopathologic features nor biological mechanisms associated with HP have been identified. Experimental Design: Among 187 patients with non–small cell lung cancer (NSCLC) treated with ICI at our institute, cases with HP were identified according to clinical and radiologic criteria. Baseline histologic samples from patients treated with ICI were evaluated by IHC for myeloid and lymphoid markers. T-cell–deficient mice, injected with human lung cancer cells and patient-derived xenografts (PDX) belonging to specific mutat…
MYC and MCL1 Cooperatively Promote Chemotherapy-Resistant Breast Cancer Stem Cells via Regulation of Mitochondrial Oxidative Phosphorylation
2017
Summary Most patients with advanced triple-negative breast cancer (TNBC) develop drug resistance. MYC and MCL1 are frequently co-amplified in drug-resistant TNBC after neoadjuvant chemotherapy. Herein, we demonstrate that MYC and MCL1 cooperate in the maintenance of chemotherapy-resistant cancer stem cells (CSCs) in TNBC. MYC and MCL1 increased mitochondrial oxidative phosphorylation (mtOXPHOS) and the generation of reactive oxygen species (ROS), processes involved in maintenance of CSCs. A mutant of MCL1 that cannot localize in mitochondria reduced mtOXPHOS, ROS levels, and drug-resistant CSCs without affecting the anti-apoptotic function of MCL1. Increased levels of ROS, a by-product of a…