CD200 is a novel p53-target gene involved in apoptosis-associated immune tolerance

Blood ◽  
2004 ◽  
Vol 103 (7) ◽  
pp. 2691-2698 ◽  
Author(s):  
Michael D. Rosenblum ◽  
Edit Olasz ◽  
Jeffery E. Woodliff ◽  
Bryon D. Johnson ◽  
Marja C. Konkol ◽  
...  

Abstract During apoptotic cell death, biochemical processes modify self-proteins and create potential autoantigens. To maintain self-tolerance in the face of natural cell turnover, the immune system must prevent or control responses to apoptosis-associated autoantigens or risk autoimmunity. The molecular mechanisms governing this process remain largely unknown. Here, we show that expression of the immunoregulatory protein CD200 increases as murine dendritic cells (DCs) undergo apoptosis. We define CD200 as a p53-target gene and identify both p53- and caspase-dependent pathways that control CD200 expression during apoptosis. CD200 expression on apoptotic DCs diminishes proinflammatory cytokine production in response to self-antigens in vitro and is required for UVB-mediated tolerance to haptenated self-proteins in vivo. Up-regulation of CD200 may represent a novel mechanism, whereby immune reactivity to apoptosis-associated self-antigens is suppressed under steady state conditions. (Blood. 2004;103: 2691-2698)

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Dong Hoon Lee ◽  
Go Woon Kim ◽  
Jung Yoo ◽  
Sang Wu Lee ◽  
Yu Hyun Jeon ◽  
...  

AbstractGlioblastoma is the most lethal brain tumor and its pathogenesis remains incompletely understood. KDM4C is a histone H3K9 demethylase that contributes to epigenetic regulation of both oncogene and tumor suppressor genes and is often overexpressed in human tumors, including glioblastoma. However, KDM4C’s roles in glioblastoma and the underlying molecular mechanisms remain unclear. Here, we show that KDM4C knockdown significantly represses proliferation and tumorigenesis of glioblastoma cells in vitro and in vivo that are rescued by overexpressing wild-type KDM4C but not a catalytic dead mutant. KDM4C protein expression is upregulated in glioblastoma, and its expression correlates with c-Myc expression. KDM4C also binds to the c-Myc promoter and induces c-Myc expression. Importantly, KDM4C suppresses the pro-apoptotic functions of p53 by demethylating p53K372me1, which is pivotal for the stability of chromatin-bound p53. Conversely, depletion or inhibition of KDM4C promotes p53 target gene expression and induces apoptosis in glioblastoma. KDM4C may serve as an oncogene through the dual functions of inactivation of p53 and activation of c-Myc in glioblastoma. Our study demonstrates KDM4C inhibition as a promising therapeutic strategy for targeting glioblastoma.


2020 ◽  
Author(s):  
Fangxian Liu ◽  
Qijin Pan ◽  
Liangliang Wang ◽  
Shijiang Yi ◽  
Peng Liu ◽  
...  

Abstract Background: Calycosin is a naturally-occurring phytoestrogen that reportedly exerts anti- nasopharyngeal carcinoma (NPC) effects. Nevertheless, the molecular mechanisms for anti-NPC using calycosin remain unrevealed. Methods: Thus, a network pharmacology was used to uncover anti-NPC pharmacological targets and mechanisms of calycosin. Additionally, validated experiments were conducted to validate the bioinformatic findings of calycosin for treating NPC. Results: As results, bioinformatic assays showed that the predictive pharmacological targets of calycosin against NPC were TP53, MAPK14, CASP8, MAPK3, CASP3, RIPK1, JUN, ESR1, respectively. And the top 20 biological processes and pharmacological mechanisms of calycosin against NPC were identified accordingly. In clinical data, NPC samples showed positive expression of MAPK14, reduced TP53, CASP8 expressions. In studies in vitro and in vivo, calycosin-dosed NPC cells resulted in reduced cell proliferation, promoted cell apoptosis. In TUNEL staining, calycosin exhibited elevated apoptotic cell number. And immunostaining assays resulted in increased TP53, CASP8 positive cells, and reduced MAPK14 expressions in calycosin-dosed NPC cells and tumor-bearing nude mice. Conclusion: Altogether, these bioinformatic findings reveal optimal pharmacological targets and mechanisms of calycosin against NPC, following with representative identification of human and preclinical experiments. Notably, some of original biotargets may be potentially used to treat NPC.


2019 ◽  
Vol 4 (2) ◽  
pp. 93-95 ◽  
Author(s):  
Jieru Wan ◽  
Honglei Ren ◽  
Jian Wang

Intracerebral haemorrhage (ICH) is a devastating type of stroke with high mortality and morbidity. However, we have few options for ICH therapy and limited knowledge about post-ICH neuronal death and related mechanisms. In the aftermath of ICH, iron overload within the perihaematomal region can induce lethal reactive oxygen species (ROS) production and lipid peroxidation, which contribute to secondary brain injury. Indeed, iron chelation therapy has shown efficacy in preclinical ICH studies. Recently, an iron-dependent form of non-apoptotic cell death known as ferroptosis was identified. It is characterised by an accumulation of iron-induced lipid ROS, which leads to intracellular oxidative stress. The ROS cause damage to nucleic acids, proteins and lipid membranes, and eventually cell death. Recently, we and others discovered that ferroptosis does occur after haemorrhagic stroke in vitro and in vivo and contributes to neuronal death. Inhibition of ferroptosis is beneficial in several in vivo and in vitro ICH conditions. This minireview summarises current research on iron toxicity, lipid peroxidation and ferroptosis in the pathomechanisms of ICH, the underlying molecular mechanisms of ferroptosis and the potential for combined therapeutic strategies. Understanding the role of ferroptosis after ICH will provide a vital foundation for cell death-based ICH treatment and prevention.


2018 ◽  
Vol 115 (50) ◽  
pp. E11721-E11730 ◽  
Author(s):  
Soo Jeong Park ◽  
Jeong Mi Kim ◽  
Jihyo Kim ◽  
Jaehark Hur ◽  
Sun Park ◽  
...  

Recent research has led to contradictory notions regarding the conventional theory that apoptotic cell death can evoke inflammatory or immunogenic responses orchestrated by released damage-associated patterns (DAMPs). By inducing IL-1β from bone marrow-derived macrophages in an effort to determine the inflammatory mediators released from apoptotic cells, we found that exosomal fractions called “apoptotic exosome-like vesicles” (AEVs) prepared from apoptotic-conditioned medium were the main inflammatory factors. These AEVs showed characteristics of exosomes in their size, density, morphology, and protein expression but had unique marker proteins, sphingosine-1-phosphate receptors 1 and 3 (S1PR1 and 3). Their biogenesis was completely dependent on cellular sphingosine-1-phosphate (S1P)/S1PRs signaling from multiple fine spindles of plasma membrane accompanied by F-actin, S1PR1, S1PR3, and CD63 at the early apoptotic phase and progressing to the maturation of F-actin–guided multivesicular endosomes mediated by Gβγ subunits of S1PRs downstream. S1P-loaded S1PRs on AEVs were critical factors for inducing IL-1β via NF-κB transcriptional factor and p38 MAPK, possibly through the RHOA/NOD2 axis, in differentiating macrophages. The AEVs induced genes of proinflammatory cytokines, chemokines, and mediators in both in vitro and in vivo models. In conclusion, AEVs could be key inflammatory mediators, acting as DAMPs that could explain the pathogeneses of various chronic inflammations, autoimmune diseases, or cancers in the future.


2002 ◽  
Vol 2 ◽  
pp. 943-948 ◽  
Author(s):  
Pidder Jansen-Dürr

Replicative senescence of human cells in primary culture is a widely accepted model for studying the molecular mechanisms of human ageing. The standard model used for studying human ageing consists of fibroblasts explanted from the skin and grown intoin vitrosenescence. From this model, we have learned much about molecular mechanisms underlying the human ageing process; however, the model presents clear limitations. In particular, a long-standing dogma holds that replicative senescence involves resistance to apoptosis, a belief that has led to considerable confusion concerning the role of apoptosis during human ageing. While there are data suggesting that apoptotic cell death plays a key role for ageingin vitroand in the pathogenesis of various age-associated diseases, this is not reflected in the current literature onin vitrosenescence. In this article, I summarize key findings concerning the relationship between apoptosis and ageingin vivoand also review the literature concerning the role of apoptosis during in vitro senescence. Recent experimental findings, summarized in this article, suggest that apoptotic cell death (and probably other forms of cell death) are important features of the ageing process that can also be recapitulated in tissue culture systems to some extent. Another important lesson to learn from these studies is that mechanisms ofin vivosenescence differ considerably between various histotypes.


2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Shujun Cao ◽  
Na Li ◽  
Xihong Liao

Abstract Background Ovarian cancer is the leading lethal gynecological cancer and is generally diagnosed during late-stage presentation. In addition, patients with ovarian cancer still face a low 5-year survival rate. Thus, innovative molecular targeting agents are required to overcome this disease. The present study aimed to explore the function of miR-362-3p and the underlying molecular mechanisms influencing ovarian cancer progression. Methods The expression levels of miR-362-3p were determined using qRT-PCR. Gain-of-function and loss-of-function methods were used to detect the effects of miR-362-3p on cell proliferation, cell migration, and tumor metastasis in ovarian cancer. A luciferase reporter assay was performed to confirm the potential target of miR-362-3p, and a rescue experiment was employed to verify the effect of miR-362-3p on ovarian cancer by regulating its target gene. Results miR-362-3p was significantly downregulated in ovarian cancer tissues and cell lines. In vitro, our data showed that miR-362-3p suppressed cell proliferation and migration. In vivo, miR-362-3p inhibited ovarian cancer growth and metastasis. Mechanistically, SERBP1 was identified as a direct target and functional effector of miR-362-3p in ovarian cancer. Moreover, SERBP1 overexpression rescued the biological function of miR-362-3p. Conclusions Our data reveal that miR-362-3p has an inhibitory effect on ovarian cancer. miR-362-3p inhibits the development and progression of ovarian cancer by directly binding its target gene SERBP1.


2019 ◽  
Author(s):  
Yong Li ◽  
Hong-Bin Ma ◽  
Chang-Ying Shi ◽  
Fei-Ling Feng ◽  
Liang Yang

AbstractIn recent years, mounting studies have shown that ACTB is closely related to various tumors. Although ACTB is dysregulated in numerous cancer types, limited data are available on the potential function and mechanism of ACTB in hepatocellular carcinoma (HCC). This study evaluated the expression and biological roles of mutant ACTB mRNA 3′UTR in HCC. Transcriptome sequence and qRT-PCR analysis determined that mutant ACTB mRNA 3′UTR was high expression in HCC tissues. Luciferase reporter assay showed that the ACTB mRNA 3′UTR mutations made it easier to interact with miR-1 and miR-29a. Moreover, mutant ACTB mRNA 3′UTR regulated miR-1 and miR-29a degradation via AGO2. Furthermore, mutant ACTB mRNA 3′UTR promoted hepatocellular carcinoma cells migration and invasionin vitroandin vivoby up-regulating miR-1 target gene MET and miR-29a target gene MCL1. In a word, our study demonstrates that 3′UTR of ACTB plays a key role in the tumor growth of hepatocellular carcinoma (HCC) and highlights the molecular mechanisms of ACTB-involved cancer growth and development.


2020 ◽  
Author(s):  
Mingliang Zhang ◽  
Weigang Dai ◽  
Zhanyu Li ◽  
Liang Tang ◽  
Jianhui Chen ◽  
...  

Abstract Background: Colorectal cancer (CRC) is the third most common cancer worldwide and the fourth most common cause of cancer death. The heat shock 70kDa protein 4 (HSPA4) participate in progression and development of cancers. However, the cellular functions, potential molecular mechanisms of HSPA4 in CRC are still largely unknown. Methods: In this study, qRT-PCR and Western Blot were used to identify the constructed HSPA4 knockdown cell lines, which was further used to construct mouse xenotransplantation models. Effects of HSPA4 knockdown on cell proliferation, apoptotic, cell cycle and migration of CRC were examined using Celigo cell counting assay, Flow cytometry, wound healing assay and Transwell assay, respectively. In addition, Human Apoptosis Antibody Array was performed to explore downstream molecular mechanism of HSPA4 in CRC cells. Results: HSPA4 was overexpressed in CRC, which was positively associated with lymphatic metastasis (N value), number of Lymph node. In addition, high expression of HSPA4 predicted poor prognosis of patients with CRC. Furthermore, HSPA4 knockdown inhibit proliferation, migration, promote apoptosis, and arrest cell cycle of CRC cells in vitro. Moreover, in vivo results supported HSPA4 knockdown inhibit tumor growth. Additionally, the induction of apoptosis of CRC cells by HSPA4 knockdown required the participation of a series of apoptosis-related proteins. The downregulation of HSPA4 promoted the progression of CRC cells, which resulted in alterations of PI3K/Akt, CCND1 and CDK6 in downstream signaling pathways. Conclusions: In sum, the downregulation of HSPA4 promoted CRC and may be a potential target for molecular therapy.


2020 ◽  
Author(s):  
Mingliang Zhang ◽  
Weigang Dai ◽  
Zhanyu Li ◽  
Liang Tang ◽  
Jianhui Chen ◽  
...  

Abstract Background Colorectal cancer (CRC) is the third most common cancer worldwide and the fourth most common cause of cancer death. The heat shock 70 kDa protein 4 (HSPA4) participate in progression and development of cancers. However, the cellular functions, potential molecular mechanisms of HSPA4 in CRC are still largely unknown. Methods In this study, qRT-PCR and Western Blot were used to identify the constructed HSPA4 knockdown cell lines, which was further used to construct mouse xenotransplantation models. Effects of HSPA4 knockdown on cell proliferation, apoptotic, cell cycle and migration of CRC were examined using Celigo cell counting assay, Flow cytometry, wound healing assay and Transwell assay, respectively. In addition, Human Apoptosis Antibody Array was performed to explore downstream molecular mechanism of HSPA4 in CRC cells. Results HSPA4 was overexpressed in CRC, which was positively associated with lymphatic metastasis (N value), number of Lymph node. In addition, high expression of HSPA4 predicted poor prognosis of patients with CRC. Furthermore, HSPA4 knockdown inhibit proliferation, migration, promote apoptosis, and arrest cell cycle of CRC cells in vitro. Moreover, in vivo results supported HSPA4 knockdown inhibit tumor growth. Additionally, the induction of apoptosis of CRC cells by HSPA4 knockdown required the participation of a series of apoptosis-related proteins. The downregulation of HSPA4 promoted the progression of CRC cells, which resulted in alterations of PI3K/Akt, CCND1 and CDK6 in downstream signaling pathways. Conclusions In sum, the downregulation of HSPA4 promoted CRC and may be a potential target for molecular therapy.


2019 ◽  
Vol 26 (25) ◽  
pp. 4799-4831 ◽  
Author(s):  
Jiahua Cui ◽  
Xiaoyang Liu ◽  
Larry M.C. Chow

P-glycoprotein, also known as ABCB1 in the ABC transporter family, confers the simultaneous resistance of metastatic cancer cells towards various anticancer drugs with different targets and diverse chemical structures. The exploration of safe and specific inhibitors of this pump has always been the pursuit of scientists for the past four decades. Naturally occurring flavonoids as benzopyrone derivatives were recognized as a class of nontoxic inhibitors of P-gp. The recent advent of synthetic flavonoid dimer FD18, as a potent P-gp modulator in reversing multidrug resistance both in vitro and in vivo, specifically targeted the pseudodimeric structure of the drug transporter and represented a new generation of inhibitors with high transporter binding affinity and low toxicity. This review concerned the recent updates on the structure-activity relationships of flavonoids as P-gp inhibitors, the molecular mechanisms of their action and their ability to overcome P-gp-mediated MDR in preclinical studies. It had crucial implications on the discovery of new drug candidates that modulated the efflux of ABC transporters and also provided some clues for the future development in this promising area.


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