Antigen presentation defects in tumors are prevalent mechanisms of adaptive immune evasion and resistance to cancer immunotherapy, whereas how tumors evade innate immunity is less clear. Using CRISPR screens, we discovered that IGSF8 expressed on tumors suppresses NK cell function by interacting with human KIR3DL2 and mouse Klra9 receptors on NK cells. IGSF8 is normally expressed in neuronal tissues and is not required for cell survival in vitro or in vivo.
View Article and Find Full Text PDFBackground: Mycosis fungoides (MF) is an indolent T-cell lymphoma that mainly affects the skin and presents with itch in more than half of the patients. Recently, the expression of Mas-related G protein-coupled receptor X2 (MRGPRX2), a receptor of mast cell (MC) responsible for the IgE-independent non-histaminergic itch, has been shown in lesional skin of patients with pruritic skin diseases, including chronic urticaria, prurigo, and mastocytosis. As of yet, limited knowledge exists regarding the MRGPRX2 expression in the skin of patients with MF.
View Article and Find Full Text PDFYAP is a key transcriptional co-activator of TEADs, it regulates cell growth and is frequently activated in cancer. In Malignant Pleural Mesothelioma (MPM), YAP is activated by loss-of-function mutations in upstream components of the Hippo pathway, while, in Uveal Melanoma (UM), YAP is activated in a Hippo-independent manner. To date, it is unclear if and how the different oncogenic lesions activating YAP impact its oncogenic program, which is particularly relevant for designing selective anti-cancer therapies.
View Article and Find Full Text PDFMillions of putative transcriptional regulatory elements (TREs) have been cataloged in the human genome, yet their functional relevance in specific pathophysiological settings remains to be determined. This is critical to understand how oncogenic transcription factors (TFs) engage specific TREs to impose transcriptional programs underlying malignant phenotypes. Here, we combine cutting edge CRISPR screens and epigenomic profiling to functionally survey ≈15,000 TREs engaged by estrogen receptor (ER).
View Article and Find Full Text PDFAXIN2 and LGR5 mark intestinal stem cells (ISCs) that require WNT/β-Catenin signaling for constant homeostatic proliferation. In contrast, AXIN2/LGR5+ pericentral hepatocytes show low proliferation rates despite a WNT/β-Catenin activity gradient required for metabolic liver zonation. The mechanisms restricting proliferation in AXIN2+ hepatocytes and metabolic gene expression in AXIN2+ ISCs remained elusive.
View Article and Find Full Text PDFCells need to preserve genome integrity despite varying cellular and physical states. p53, the guardian of the genome, plays a crucial role in the cellular response to DNA damage by triggering cell cycle arrest, apoptosis or senescence. Mutations in p53 or alterations in its regulatory network are major driving forces in tumorigenesis.
View Article and Find Full Text PDFThe tumor suppressor protein p53 is inactive in a large number of cancers, including some forms of sarcoma, breast cancer, and leukemia, due to overexpression of its intrinsic inhibitors MDM2 and MDMX. Reactivation of p53 tumor suppressor activity, via disruption of interactions between MDM2/X and p53 in the cytosol, is a promising strategy to treat cancer. Peptides able to bind MDM2 and/or MDMX were shown to prevent MDM2/X:p53 interactions, but most possess low cell penetrability, low stability, and/or high toxicity to healthy cells.
View Article and Find Full Text PDFTo enable reliable cell fate decisions, mammalian cells need to adjust their responses to dynamically changing internal states by rewiring the corresponding signaling networks. Here, we combine time-lapse microscopy of endogenous fluorescent reporters with computational analysis to understand at the single-cell level how the p53-mediated DNA damage response is adjusted during cell cycle progression. Shape-based clustering revealed that the dynamics of the CDK inhibitor p21 diverges from the dynamics of its transcription factor p53 during S phase.
View Article and Find Full Text PDFThe cytokine TGFβ provides important information during embryonic development, adult tissue homeostasis, and regeneration. Alterations in the cellular response to TGFβ are involved in severe human diseases. To understand how cells encode the extracellular input and transmit its information to elicit appropriate responses, we acquired quantitative time-resolved measurements of pathway activation at the single-cell level.
View Article and Find Full Text PDFSynchrotron radiation (SR) X-ray has wide biomedical applications including high resolution imaging and brain tumor therapy due to its special properties of high coherence, monochromaticity and high intensity. However, its interaction with biological tissues remains poorly understood. In this study, we used the rat testis as a model to investigate how SR X-ray would induce tissue responses, especially the blood-testis barrier (BTB) because BTB dynamics are critical for spermatogenesis.
View Article and Find Full Text PDFPurposes: Synchrotron radiation (SR) X-ray has great potential for cancer treatment and medical imaging. It is of significance to investigate the mechanisms underlying the effects of SR X-ray irradiation on biological tissues, and search for the strategies for preventing the damaging effects of SR X-ray irradiation on normal tissues. The major aim of our current study is to test our hypothesis that poly(ADP-ribose) polymerase (PARP) plays a significant role in SR X-ray-induced tissue damage.
View Article and Find Full Text PDFInt J Physiol Pathophysiol Pharmacol
October 2012
Synchrotron radiation (SR) X-ray has characteristic properties such as coherence and high photon flux, which has excellent potential for its applications in medical imaging and cancer treatment. However, there is little information regarding the mechanisms underlying the damaging effects of SR X-ray on biological tissues. Oxidative stress plays an important role in the tissue damage induced by conventional X-ray, while the role of oxidative stress in the tissue injury induced by SR X-ray remains unknown.
View Article and Find Full Text PDFInt J Physiol Pathophysiol Pharmacol
October 2012
Synchrotron radiation (SR) X-ray has great potential for its applications in medical imaging and cancer treatment. In order to apply SR X-ray in clinical settings, it is necessary to elucidate the mechanisms underlying the damaging effects of SR X-ray on normal tissues, and to search for the strategies to reduce the detrimental effects of SR X-ray on normal tissues. However, so far there has been little information on these topics.
View Article and Find Full Text PDFNumerous studies have indicated that four interacting factors, including oxidative stress, mitochondrial alterations, calcium dyshomeostasis and inflammation, play crucial pathological roles in multiple major neurological diseases, including stroke, Alzheimer's disease (AD) and Parkinson's disease (PD). Increasing evidence has also indicated that NAD(+) plays important roles in not only mitochondrial functions and energy metabolism, but also calcium homeostasis and inflammation. The key NAD(+)-consuming enzyme--poly(ADP-ribose) polymerase-1 (PARP-1) and sirtuins--have also been shown to play important roles in cell death and aging, which are two key factors in the pathology of multiple major age-dependent neurological diseases: PARP-1 plays critical roles in both inflammation and oxidative stress-induced cell death; and sirtuins also mediate the process of aging, cell death and inflammation.
View Article and Find Full Text PDFBiochem Biophys Res Commun
January 2012
SIRT2 is a tubulin deacetylase, which can play either detrimental or beneficial roles in cell survival under different conditions. While it has been suggested that reduced SIRT2 expression in human gliomas may contribute to development of gliomas, there has been no study that directly determines the effects of decreased SIRT2 activity on the survival of glioma cells. In this study we applied both pharmacological and molecular approaches to determine the roles of SIRT2 in the survival of glioma cells.
View Article and Find Full Text PDFInt J Physiol Pathophysiol Pharmacol
October 2012
Synchrotron radiation (SR) X-ray has great potential for its applications in both diagnosis and treatment of diseases, due to its characteristic properties including coherence, collimation, monochromaticity, and exceptional brightness. Great advances have been made regarding potential medical applications of SR X-ray in recent years, particularly with the development of the third generation of SR light sources. However, multiple studies have also suggested damaging effects of SR X-ray on biological samples ranging from protein crystals to cells and biological tissues.
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