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Liquid biopsies represent a valid alternative to conventional tissue biopsies, offering a real time molecular picture of tumors in a minimally invasive manner. Of the various circulating biomarkers available for liquid biopsy, circulating tumor cells (CTC) and circulating tumor DNA (ctDNA) are the most intensively studied to date. However, CTC and ctDNA represent different tumor components, therefore, complementary information from both sources might be beneficial. This protocol focuses on the description of a sample processing workflow that allowed for concurrent isolation of CTC and ctDNA from the same source sample. This single tube approach enables simultaneous analysis of multiple biomarkers to better monitor cancer drug resistance.Dormant or slow-cycling tumor cells can form a residual chemoresistant reservoir responsible for relapse in patients, years after curative surgery and adjuvant therapy. Slow-cycling cancer cells (SCCC) represent a cellular status rather than a cell population present in a minor proportion, even in growing tumors. We have adapted the pulse-chase expression of histone H2B fused to enhanced GFP (H2BeGFP) for labelling and isolating SCCC. SCCC show cancer-initiation potential and enhanced chemoresistance, and present a distinctive nongenetic and cell-autonomous gene expression profile shared across different tumor types. The use of our H2BeGFP pulse-chase method opens the possibility to study live SCCC in any growing tissue either cancerous or normal.The vast majority of cancer deaths are the result of drug resistance. [https://www.selleckchem.com/products/ABT-888.html selleckchem] The lack of superior preclinical models that better reflect the complexity of relapsed disease hinders the development of novel therapeutics. 2D and 3D in vitro cell-based assays have provided some information, but this is limited and does not consider the role of the tumor microenvironment. The development of an in vivo assay can allow to generate resistance, while taking into account the role of the tumor microenvironment and the tumor structure. To achieve this, we have developed an in vivo dose-escalation protocol that models the acquisition of resistance. This model of chemo-resistant neuroblastoma presented with metastases and a genetic signature characteristic of clinical relapsed tumors (Yogev et al. Cancer Res. 795382-5393, 2019). We believe that this protocol can be used to generate faithful models for other types of relapse disease; these could serve as reliable tools while developing novel therapies.Current concepts in treating cancer usually neglect individual tumor characteristics such as a given mutational make up. Consequently, a "one-size-fits-all" therapeutic concept may commonly fail in terms of efficacy, evolving drug resistance, and side effects. In times of omics, novel elaborated and personalized approaches emerge for efficiently eradicate cancer cells, while sparing healthy cells. Synthetic lethality-based strategies offer promising opportunities to exploit tumor-specific vulnerabilities and improve tolerability. Furthermore, taking advantage of putative synergistic interaction between synthetic lethal drugs specifically targeting a given tumor genotype, could further enhance efficacy and tolerability, thus preventing drug resistance. Mechanisms of drug resistance in cancers are manifold but critical to assess, in view of restoring drug sensibility. In this chapter, we provide a framework to investigate synthetic lethality and synergistic interactions, as well as drug resistance in cancer cells in vitro.Breast cancer (BC) is a leading cause of cancer death among women worldwide. To better understand and predict therapeutic response in BC patient developing a fast, low-cost, and reliable preclinical tumor from patient's tumor specimen is needed. Here, we describe the development of a preclinical model of BC through the generation and ex vivo culture of patient-derived organotypic tumor spheroids (PDOTS) in a 3D microfluidic device. Moreover, the real-time screening of conventional chemotherapy agents on cultured PDOTS is also described.Microfluidic devices have become a promising alternative approach for cellular co-culture. Many approaches incorporate a semipermeable barrier to physically separate, yet chemically connect, two cell types; however, the majority of these approaches utilize batch culture conditions which can result in nutrient depletion and waste accumulation. This chapter describes an alternative approach that allows for the continuous infusion of media, relieving the constraints of batch culture. The microfluidic device consists of two separate layers a bottom layer of 3% (w/v) agarose to facilitate chemical diffusion and a top polydimethylsiloxane (PDMS) layer into which four parallel fluidic channels were imprinted. The microfluidic approach allows for facile visualization of cells with light microscopy and the ability to add (or subtract) drugs or biomolecules to interrogate the system or modulate the cellular response. Finally, the approach allows for terminal immunostaining of either (or both) cell types.Breast cancer is a complex and heterogeneous pathology, characterized by a variety of histological and molecular phenotypes. The majority of the breast cancers express the estrogen receptor alpha (ER), which plays a pivotal role in the pathobiology of the disease and are therefore classified as ER-positive (ER+). In fact, targeting of the ER signaling pathway is the main therapeutic strategy for ER+ breast cancer. Despite the success of endocrine therapy, intrinsic and acquired resistance are reported in 30-50% of the ER+ breast cancers. However, the mechanisms underlying ER heterogeneity and therapeutic resistance are far from being fully disclosed, and efficacious clinical strategies to overcome resistance are still pending. One of the hurdles in studying ER+ breast cancer resistance is related with the scarcity of experimental models that can recapitulate ER heterogeneity and signaling. This is the case of ER+ breast cancer cell models, typically based on cells derived from metastasis, which also fail to r Exp Clin Cancer Res 39161, 2020), based on electrostatically driven breast cancer tissue encapsulation in alginate, coupled to culture under agitation in a defined culture medium. We also describe challenge of the ex vivo model with an ER activator and inhibitors (anti-endocrine drugs) and a gene expression endpoint of drug response using reverse transcription PCR-based analysis of three distinct genes downstream of ER.3D cultures of cancer cells enable better mimicking of physiological conditions compared to traditional monolayer 2D cultures. Here we describe alginate scaffold-based model that can be used in both static and biomimetic conditions for studying drug sensitivity in cancer cells and multidrug resistance (MDR) mechanisms. This 3D culture model resembles in vivo conditions and provides relevant and reproducible results. It is easy to set up and allows for facile manipulation for downstream analyses. All these remarkable features make this 3D culture model a promising tool in drug discovery and cancer cell biology research.<br /><br /> Age-related physiological changes, particularly immune system decline, may contribute to greater vulnerability to infectious diseases in older individuals. A growing body of evidence shows that both, acute, and chronic infections may be accompanied by cognitive disturbances as part of their manifestations. Given the importance of cognition in aging trajectories, the objective of this article was to review current knowledge on cognitive outcomes of infectious diseases in older adults, and to emphasize the importance of considering cognition as a domain of interest in its own rights in these diseases.<br /><br /> A MEDLINE/PubMed database search was conducted to identify articles reporting cognitive impairment associated with various severe acute infections and specific chronic infectious conditions such as human immune deficiency virus, the herpes virus family, hepatitis C virus, Lyme borreliosis, Helicobacter pylori, periodontitis, and emerging pathogens like SARS-CoV-2, as well as potentially preventive strategies like vaccination.<br /><br /> Taken together, the studies examined in the present review emphasize that numerous acute and chronic infectious diseases share mechanisms that, when added to specific risk factors frequently found in older persons, contribute to considerably increase the risk of cognitive outcomes such as cognitive decline and dementia. This review may help to appreciate the role that infectious diseases play in cognitive trajectories and thus promote further investigation on the topic.<br /><br />Taken together, the studies examined in the present review emphasize that numerous acute and chronic infectious diseases share mechanisms that, when added to specific risk factors frequently found in older persons, contribute to considerably increase the risk of cognitive outcomes such as cognitive decline and dementia. This review may help to appreciate the role that infectious diseases play in cognitive trajectories and thus promote further investigation on the topic.Immune checkpoint receptors (ICR) modulate the immune response and are critical hubs for immunotherapy. However, data on their role in T lymphoid malignancies, such as cutaneous T cell lymphoma (CTCL), is sparse. We aimed to explore the role of ICR in the malignant features of transformed T lymphocytes and evaluate the effect of ICR-targeting monoclonal antibodies, often used as immunotherapy for solid tumors. We used the CTCL cell line HH and the Sézary cell line Hut78 to examine ICR expression and the effects of ICR inhibition on cell viability and proliferation. Despite their shared T cell progeny, the different CTCL cell lines exhibit markedly different ICR expression profiles. Programmed cell death-ligand 1 (PD-L1) was expressed by both cell lines, while programmed death-1 (PD-1) was expressed only by the HH cell line. Common to all malignant T cells was an autonomous hyper-proliferative state that did not require T cell receptor stimulation. A monoclonal antibody blocking PD-1 had a small but statistically significant augmenting effect on T cell proliferation. Of note, when the cells were exposed to ionizing radiation, healthy lymphocytes and those derived from the HH cell line were salvaged by anti-PD-L1. We show a regulatory role of ICR, mainly PD-1 and its ligand PD-L1, on cutaneous T cell malignancy.The aim of this study was to investigate the effects of different levels of maca powder supplementation (0.0, 0.5, 1.0, 1.5, 2.0, and 2.5 g/kg) in the diet on performance, carcass characteristics, serum biochemical constituents and hormone concentrations, bone biomechanical properties, and ileum histomorphology in growing Japanese quails. In this 42-day trial, a total of 480 mixed sex Japanese quail chicks, aged 1 day, were randomly distributed among six experimental groups. Each experimental group contained four replicates of 20 chicks each. The addition of 2.0 g/kg of maca powder to the diet significantly decreased body weight, body weight gain compared to the control group (P  less then  0.05). In addition, with the 1.5 g/kg level of maca powder, feed efficiency improved considerably (P  less then  0.05). The testis weight increased significantly with the addition of maca powder at 1.0 g/kg level to the diet, and testesteron concentration of serum in male quails was also increased significantly at 1.5 g/kg level of maca powder compared to control group (P  less then  0.