Tumor necrosis factor alpha-induced phosphorylation of RelA/p65 on Ser529 is controlled by casein kinase II

NF-κB signaling and its anti-apoptotic effects in liver & skeletal muscle of dehydrated Xenopus laevis

The African clawed frog, Xenopus laevis, is able to survive prolonged arid conditions during seasonal droughts. During these conditions, X. laevis enters aestivation whereby its metabolic rate is suppressed, urea and ammonia levels increase, and its physiological functions slow. Various molecular mechanisms are employed by X. laevis to mitigate the deleterious effects of severe dehydration and hypometabolism, including pro-survival cellular processes that protect cells and tissues from damage and atrophy. While previous research has focused on antioxidant proteins' role in preventing oxidative stress, information on the role of anti-apoptotic signaling in X. laevis is lacking. As such, we investigated the role of nuclear factor-kappa B (NF-κB) signaling and its downstream target genes in liver and skeletal muscle tissue of X. laevis. The transcription factor, NF-κB, and its downstream target genes work to inhibit apoptotic machinery and promote cell survival. Herein, we found that NF-κB signaling activation in liver tissue leads to the selective upregulation of downstream anti-apoptotic proteins. In contrast, this upregulation occurs independently of NF-κB signaling in skeletal muscle tissue. Overall, our results serve to expand our knowledge of the anti-apoptotic mechanisms underlying the natural dehydration-tolerance of X. laevis, including its likely use in mitigating tissue atrophy during aestivation.

CK2: The master regulator in tumor immune-microenvironment - A crucial target in oncotherapy

A constitutively active serine/threonine kinase, casein kinase 2 (CK2) is involved in several physiological functions, such as DNA repair, apoptosis, and cell cycle control. New research emphasizes how critical CK2 is to the immune system's dysregulation in the tumor immune-microenvironment (TIME). The inhibition of immunological responses, including the downregulation of immune effector cells and the elevation of immunosuppressive proteins that aid in the development of tumor and immune evasion, has been linked to CK2 overexpression. CK2 maintains an immunosuppressive milieu that impedes anti-tumor immunity by encouraging the expressions and activities of immune checkpoint markers, regulating cytokines release, and boosting immune-suppressive cells such as regulatory T cells (Tregs) and myeloid-derived suppressor cells (MDSCs) to maintain immune evasion. It is a promising target for cancer treatment due to its complex role in immune regulation and oncogenic pathways. In this study, we address the therapeutic perspectives of targeting CK2 in oncotherapy and investigate the mechanisms by which it controls immunological responses in the TME. This review, comprehending the function of CK2 in immune suppression can facilitate the creation of innovative treatment approaches aimed at augmenting anti-tumor immunity and enhancing immunotherapy effectiveness.

10-Hydroxydec-2-enoic acid reduces vascular smooth muscle cell inflammation via interacting with Toll-like receptor 4

BACKGROUND

10-Hydroxydec-2-enoic acid (10-HDA), a unique and marker compound in royal jelly, has a wide range of bio-activities. However, its role in regulating inflammation of vascular smooth muscle cell (VSMC), which is essential to a set of vascular diseases, is still unknown.

PURPOSE

Our study aimed to investigate whether 10-HDA exerts effect on VSMC inflammation via interacting with toll-like receptor 4 (TLR4), a pivotal inflammatory initiator.

METHODS

A package of proteins, which might participate in TLR4-mediated signaling, influenced by 10-HDA were analyzed in mouse VSMCs with Angiotensin Ⅱ(Ang Ⅱ) or lipopolysaccharide (LPS) stimulation. Accordingly, pro- or anti-inflammatory cytokines, reactive oxygen species (ROS), and anti-oxidants that are closely relevant to inflammatory process were determined. The possible mode for 10-HDA interacting with TLR4 was also characterized. Moreover, involvement of a key miRNA in 10-HDA regulating VSMC inflammation was identified.

RESULTS

In the presence of Ang Ⅱ, 10-HDA inhibited the TLR4 expression in a dose-dependent manner. In such occasion, 10-HDA hindered the up-regulation of specificity protein 1 (SP1) and serine/threonine-protein phosphatase 6 catalytic subunit (PPP6C), the phosphorylation of extracellular signal-regulated kinase 1/2, TGF-β-activated kinase 1, and nuclear factor-κB p56, as well as the enhancement of myeloid differentiation primary response gene 88. Apart from SP1 and PPP6C, the level change of these proteins by 10-HDA was similar with LPS stimulation. The effect might be resulted from 10-HDA blocking TLR4 through multiple atomic interactions. 10-HDA mitigated the increase of pro-inflammatory cytokines tumor necrosis factor-alpha, interleukin-2 (IL-2), and IL-6, as well as increased the anti-inflammatory cytokine IL-10, in the Ang Ⅱ- or LPS-induced VSMCs. Correspondingly, the level of ROS was attenuated and the anti-oxidants such as glutathione and superoxide dismutase were fortified. The data indicated the anti-inflammatory potential of 10-HDA in VSMCs, which was associated with 10-HDA's capability of relieving oxidative stress. Additionally, the expression of miR-17-5p was saved by 10-HDA from Ang Ⅱ- or LPS-treated VSMCs, which might be relevant to SP1 and PPP6C targeting.

CONCLUSION

The present work of 10-HDA, for the first time, revealed its ability to alleviate VSMC inflammation by targeting TLR4 and therefore modulate the downstream inflammatory participants. Our data will cast light on the utilization of 10-HDA in VSMC inflammation-related vascular disorders.

TBB inhibits CK2/PD-L1/EGFR pathway-mediated tumor progression

The expression of PD-L1 on cancer cells facilitates tumor immune escape by binding to PD-1 on T cells, thereby inhibiting T cell activity. However, the role of intracellular PD-L1 signaling in tumor progression remains unclear. In this study, we demonstrate that CK2 induces PD-L1 phosphorylation at Thr-285, which enhances PD-L1 protein stability. This phosphorylation disrupts the interaction between LC3B and PD-L1, inhibiting PD-L1 degradation via autophagy. Furthermore, PD-L1-T285 phosphorylation promotes EGFR binding to PD-L1, leading to activation of EGFR downstream signaling. This activation drives non-small cell lung cancer (NSCLC) cell proliferation, migration, invasion, and tumor growth. Conversely, CK2 depletion or treatment with a CK2 inhibitor reversed these effects. Our findings reveal a novel mechanism by which the CK2/PD-L1/EGFR pathway promotes tumor progression.

Macrophage WEE1 Directly Binds to and Phosphorylates NF-κB p65 Subunit to Induce Inflammatory Response and Drive Atherosclerosis

Atherosclerosis has an urgent need for new therapeutic targets. Protein kinases orchestrate multiple cellular events in atherosclerosis and may provide new therapeutic targets for atherosclerosis. Here, a protein kinase, WEE1 G2 checkpoint kinase (WEE1), promoting inflammation in atherosclerosis is identified. Kinase enrichment analysis and experimental evidences reveal macrophage WEE1 phosphorylation at S642 in human and mouse atherosclerotic tissues. RNA-seq analysis, combined with experiment studies using mutant WEE1 plasmids, shows that WEE1 phosphorylation, rather than WEE1 expression, mediated oxLDL-induced inflammation in macrophages. Macrophage-specific deletion of WEE1 or pharmacological inhibition of WEE1 kinase activity attenuates atherosclerosis by reducing inflammation in mice. Mechanistically, RNA-seq and co-immunoprecipitation followed by proteomics analysis are used to explore the mechanism and substrate of WEE1. p-WEE1 promoted inflammatory response through activating NF-κB shown and further revealed that WEE1 can directly bind to the p65 subunit. It is confirmed that p-WEE1 directly interacts with the RHD domain of p65 and phosphorylates p65 at S536, thereby facilitating subsequent NF-κB activation and inflammatory response in macrophages. The findings demonstrate that macrophage WEE1 drives NF-κB activation and atherosclerosis by directly phosphorylating p65 at S536. This study identifies WEE1 as a new upstream kinase of p65 and a potential therapeutic target for atherosclerosis.

Versatile roles of disordered transcription factor effector domains in transcriptional regulation

Transcription, a crucial step in the regulation of gene expression, is tightly controlled and involves several essential processes, such as chromatin organization, recognition of the specific genomic sequences, DNA binding, and ultimately recruiting the transcriptional machinery to facilitate transcript synthesis. At the center of this regulation are transcription factors (TFs), which comprise at least one DNA-binding domain (DBD) and an effector domain (ED). Although the structure and function of DBDs have been well studied, our knowledge of the structure and function of effector domains is limited. EDs are of particular importance in generating distinct transcriptional responses between protein members of the same TF family that have similar DBDs and specificities. The study of transcriptional activity conferred by effector domains has traditionally been conducted through examining protein-protein interactions. However, recent research has uncovered alternative mechanisms by which EDs regulate gene expression, such as the formation of condensates that increase the local concentration of transcription factors, cofactors, and coregulated genes, as well as DNA binding. Here, we provide a comprehensive overview of the known roles of transcription factor EDs, with a specific focus on disordered regions. Additionally, we emphasize the significance of intrinsically disordered regions (IDRs) during transcriptional regulation. We examine the mechanisms underlying the establishment and maintenance of transcriptional specificity through the structural properties of predominantly disordered EDs. We then provide a comprehensive overview of the current understanding of these domains, including their physical and chemical characteristics, as well as their functional roles.

Buffalo Immune Competence Under Infectious and Non-Infectious Stressors

Immune competence is a critical aspect of protecting animals from the negative consequences of disease. The activation of the immune response from inflammation is part of adaptive homeostasis that serves to eliminate danger, induce tissue repair, and restore tissue homeostasis. Therefore, the main goal for the organism is to control both the induction and suppression of inflammation and resist the onset of disease. In this condition, modulators of inflammatory responses are produced, including small proteins called cytokines, which exert a pro- or anti-inflammatory action in a context-dependent manner. Indeed, the cytokine profile could be considered a useful biomarker to determine the pathophysiology of certain diseases, such as mastitis, endometritis, change-induced heat stress, and zoonoses. Recently, buffalo breeding has attracted the interest of the research communities due to their high resilience; however, little is known about the immune mechanism activated under specific stressors. This review describes the complex immune competence of the buffalo in the presence of the most common infectious and non-infectious stressors. In addition, a brief description of methods for early diagnosis of disease using cytokine quantification will be introduced.

Body weight control via protein kinase CK2: diet-induced obesity counteracted by pharmacological targeting

BACKGROUND

Protein kinase CK2 is a highly conserved enzyme implicated in the pathogenesis of various human illnesses including obesity. Despite compelling evidence for the involvement of this kinase in the pathophysiology of obesity, the molecular mechanisms by which CK2 might regulate fat metabolism are still poorly understood.

METHODS AND RESULTS

In this study, we aimed to elucidate the role of CK2 on lipid metabolism by employing both in vitro and in vivo approaches using mouse pre-adipocytes and a mouse model of diet-induced obesity. We show that pharmacological inhibition of CK2 by CX-4945 results in premature upregulation of p27KIP1 preventing the progression of cells into mature adipocytes by arresting their development at the intermediate phase of adipogenic differentiation. Consistent with this, we show that in vivo, CK2 regulates the expression levels and ERK-mediated phosphorylation of C/EBPβ, which is one of the earliest transcription factors responsive to adipogenic stimuli. Furthermore, we demonstrate the functional implication of CK2 in the expression of late markers of adipogenesis and factors regulating lipogenesis in liver and white adipose tissue. Finally, we show that while mice subjected to high-fat diet increased their body weight, those additionally treated with CX-4945 gained considerably less weight. NMR-based body composition analysis revealed that this is linked to significant differences in body fat mass.

CONCLUSIONS

Taken together, our study provides novel insights into the role of CK2 in fat metabolism in response to chronic lipid overload and confirms CK2 pharmacological targeting as a potentially powerful strategy for body weight control and/or the treatment of obesity and related metabolic disorders.

Critical role of protein kinase CK2 in chronic myeloid leukemia cells harboring the T315I BCR::ABL1 mutation

Chronic myeloid leukemia (CML) is characterized by the fusion protein BCR::ABL1, a constitutively active tyrosine kinase. The frontline treatment, represented by tyrosine kinase inhibitors (TKIs), has dramatically improved the clinical outcomes of patients. However, TKI resistance through various mechanisms has been reported. In particular, the BCR::ABL11 T315I mutation is associated with resistance to first- and second-generation TKIs and poor survival outcomes. For patients harboring this mutation, treatments with third generation TKIs are indicated, which are however accompanied by adverse events. Protein kinase CK2 is implicated in several human diseases. Although its role in CML has already been proven, its essentialness in T315I-mediated TKI resistance has yet to be investigated. Here we show that CK2 contributes to the aberrantly high signaling pathways in T315I-cells, and that its pharmacological or genetic targeting diminishes those signals, induces apoptosis, and reduces the proliferation and clonogenic potential of T315I-cells. The effects of CK2 inhibition are also observed in the presence of bone marrow stromal cells and under hypoxic conditions, and, remarkably, in patient-derived cells. Moreover, CK2 inhibition or genetic ablation of the CK2α catalytic subunit sensitizes T315I-cells towards TKIs. Collectively, our results suggest the potential benefit of inhibiting CK2 in CML characterized by T315I-dependent resistance.

Nucleolar casein kinase 2 alpha as a prognostic factor in patients with surgically resected early‑stage lung adenocarcinoma

Lung cancer remains a leading cause of global cancer‑related deaths, therefore the identification of prognostic factors for lung cancer is critical. Casein kinase 2 alpha (CK2α) is one of the driver kinases in various cancers, and it was previously demonstrated that CK2α localization was associated with a poor prognosis in invasive breast cancer. In the present study, the importance of CK2α in the nucleolus was explored as a potential prognostic marker for surgically resected early‑stage lung adenocarcinoma. The present study included 118 patients who underwent pulmonary lobectomy between 2014 and 2018 in Fukushima Medical University Hospital (Fukushima, Japan), and in whom CK2α localization in tumor samples was assessed by immunohistochemistry. Patient and tumor characteristics, including pathological stage, histological type and histological grade, were analyzed. Recurrence‑free survival (RFS) and overall survival were evaluated in relation to nucleolar CK2α staining. CK2α staining in the nucleoli was observed in 50.8% of lung adenocarcinoma tumors. Positive nucleolar CK2α staining was independent of pathological stage, histological type and histological grade. Patients with positive nucleolar CK2α staining exhibited significantly worse RFS compared with patients with negative staining. Multivariate analysis identified nucleolar CK2α staining and lymph node metastasis as independent poor prognostic factors. The results of the present study suggested that nucleolar CK2α staining is a novel and independent prognostic factor in surgically resected early‑stage lung adenocarcinoma. These findings indicated the potential of nucleolar CK2α as a predictive biomarker for future recurrence, and a guide to treatment decisions. Further research is required, particularly in understanding the molecular mechanisms linking nucleolar CK2α to recurrence.

Protein kinase CK2 sustains de novo fatty acid synthesis by regulating the expression of SCD-1 in human renal cancer cells

BACKGROUND

Clear cell renal cell carcinoma (ccRCC) is a type of cancer characterized by a vast intracellular accumulation of lipids that are critical to sustain growth and viability of the cells in the tumour microenvironment. Stearoyl-CoA 9-desaturase 1 (SCD-1) is an essential enzyme for the synthesis of monounsaturated fatty acids and consistently overexpressed in all stages of ccRCC growth.

METHODS

Human clear cell renal cell carcinoma lines were treated with small-molecule inhibitors of protein kinase CK2. Effects on the expression levels of SCD-1 were investigated by RNA-sequencing, RT-qPCR, Western blot, and in vivo studies in mice. Phase-contrast microscopy, fluorescence microscopy, flow cytometry, and MALDI-mass spectrometry analysis were carried out to study the effects on endogenous lipid accumulation, induction of endoplasmic reticulum stress, rescue effects induced by exogenous MUFAs, and the identity of lipid populations. Cell proliferation and survival were investigated in real time employing the Incucyte® live-cell analysis system. Statistical significance was determined by applying the two-tailed Student's t test when comparing two groups of data whereas the two-way ANOVA, multiple Tukey's test was employed for multiple comparisons.

RESULTS

Here, we show that protein kinase CK2 is critical for preserving the expression of SCD-1 in ccRCC lines maintained in culture and heterotransplanted into nude mice. Consistent with this, pharmacological inhibition of CK2 leads to induction of endoplasmic reticulum stress linked to unfolded protein response activation and decreased proliferation of the cells. Both effects could be reversed by supplementing the growth medium with oleic acid indicating that these effects are specifically caused by reduced expression of SCD-1. Analysis of lipid composition by MALDI-mass spectrometry revealed that inhibition of CK2 results in a significant accumulation of the saturated palmitic- and stearic acids.

CONCLUSIONS

Collectively, our results revealed a previously unidentified molecular mechanism regulating the synthesis of monounsaturated fatty acids corroborating the notion that novel therapeutic approaches that include CK2 targeting, may offer a greater synergistic anti-tumour effect for cancers that are highly dependent on fatty acid metabolism.

Post-translational modifications of p65: state of the art

P65, a protein subunit of NF-κB, is a widely distributed transcription factor in eukaryotic cells and exerts diverse regulatory functions. Post-translational modifications such as phosphorylation, acetylation, methylation and ubiquitination modulate p65 transcriptional activity and function, impacting various physiological and pathological processes including inflammation, immune response, cell death, proliferation, differentiation and tumorigenesis. The intricate interplay between these modifications can be antagonistic or synergistic. Understanding p65 post-translational modifications not only elucidates NF-κB pathway regulation but also facilitates the identification of therapeutic targets and diagnostic markers for associated clinical conditions.

Chromatin modifier Hmga2 promotes adult hematopoietic stem cell function and blood regeneration in stress conditions

The molecular mechanisms governing the response of hematopoietic stem cells (HSCs) to stress insults remain poorly defined. Here, we investigated effects of conditional knock-out or overexpression of Hmga2 (High mobility group AT-hook 2), a transcriptional activator of stem cell genes in fetal HSCs. While Hmga2 overexpression did not affect adult hematopoiesis under homeostasis, it accelerated HSC expansion in response to injection with 5-fluorouracil (5-FU) or in vitro treatment with TNF-α. In contrast, HSC and megakaryocyte progenitor cell numbers were decreased in Hmga2 KO animals. Transcription of inflammatory genes was repressed in Hmga2-overexpressing mice injected with 5-FU, and Hmga2 bound to distinct regions and chromatin accessibility was decreased in HSCs upon stress. Mechanistically, we found that casein kinase 2 (CK2) phosphorylates the Hmga2 acidic domain, promoting its access and binding to chromatin, transcription of anti-inflammatory target genes, and the expansion of HSCs under stress conditions. Notably, the identified stress-regulated Hmga2 gene signature is activated in hematopoietic stem progenitor cells of human myelodysplastic syndrome patients. In sum, these results reveal a TNF-α/CK2/phospho-Hmga2 axis controlling adult stress hematopoiesis.

Global Interactome Mapping Reveals Pro-tumorigenic Interactions of NF-κB in Breast Cancer

NF-κB pathway is involved in inflammation; however, recent data shows its role also in cancer development and progression, including metastasis. To understand the role of NF-κB interactome dynamics in cancer, we study the complexity of breast cancer interactome in luminal A breast cancer model and its rearrangement associated with NF-κB modulation. Liquid chromatography-mass spectrometry measurement of 160 size-exclusion chromatography fractions identifies 5460 protein groups. Seven thousand five hundred sixty eight interactions among these proteins have been reconstructed by PrInCE algorithm, of which 2564 have been validated in independent datasets. NF-κB modulation leads to rearrangement of protein complexes involved in NF-κB signaling and immune response, cell cycle regulation, and DNA replication. Central NF-κB transcription regulator RELA co-elutes with interactors of NF-κB activator PRMT5, and these complexes are confirmed by AlphaPulldown prediction. A complementary immunoprecipitation experiment recapitulates RELA interactions with other NF-κB factors, associating NF-κB inhibition with lower binding of NF-κB activators to RELA. This study describes a network of pro-tumorigenic protein interactions and their rearrangement upon NF-κB inhibition with potential therapeutic implications in tumors with high NF-κB activity.

Quantitative Proteomics Reveal That CB2R Agonist JWH-133 Downregulates NF-κB Activation, Oxidative Stress, and Lysosomal Exocytosis from HIV-Infected Macrophages

HIV-associated neurocognitive disorders (HAND) affect 15-55% of HIV-positive patients and effective therapies are unavailable. HIV-infected monocyte-derived macrophages (MDM) invade the brain of these individuals, promoting neurotoxicity. We demonstrated an increased expression of cathepsin B (CATB), a lysosomal protease, in monocytes and post-mortem brain tissues of women with HAND. Increased CATB release from HIV-infected MDM leads to neurotoxicity, and their secretion is associated with NF-κB activation, oxidative stress, and lysosomal exocytosis. Cannabinoid receptor 2 (CB2R) agonist, JWH-133, decreases HIV-1 replication, CATB secretion, and neurotoxicity from HIV-infected MDM, but the mechanisms are not entirely understood. We hypothesized that HIV-1 infection upregulates the expression of proteins associated with oxidative stress and that a CB2R agonist could reverse these effects. MDM were isolated from healthy women donors (n = 3), infected with HIV-1ADA, and treated with JWH-133. After 13 days post-infection, cell lysates were labeled by Tandem Mass Tag (TMT) and analyzed by LC/MS/MS quantitative proteomics bioinformatics. While HIV-1 infection upregulated CATB, NF-κB signaling, Nrf2-mediated oxidative stress response, and lysosomal exocytosis, JWH-133 treatment downregulated the expression of the proteins involved in these pathways. Our results suggest that JWH-133 is a potential alternative therapy against HIV-induced neurotoxicity and warrant in vivo studies to test its potential against HAND.

Curcumin in Cancer and Inflammation: An In-Depth Exploration of Molecular Interactions, Therapeutic Potentials, and the Role in Disease Management

This paper delves into the diverse and significant roles of curcumin, a polyphenolic compound from the Curcuma longa plant, in the context of cancer and inflammatory diseases. Distinguished by its unique molecular structure, curcumin exhibits potent biological activities including anti-inflammatory, antioxidant, and potential anticancer effects. The research comprehensively investigates curcumin's molecular interactions with key proteins involved in cancer progression and the inflammatory response, primarily through molecular docking studies. In cancer, curcumin's effectiveness is determined by examining its interaction with pivotal proteins like CDK2, CK2α, GSK3β, DYRK2, and EGFR, among others. These interactions suggest curcumin's potential role in impeding cancer cell proliferation and survival. Additionally, the paper highlights curcumin's impact on inflammation by examining its influence on proteins such as COX-2, CRP, PDE4, and MD-2, which are central to the inflammatory pathway. In vitro and clinical studies are extensively reviewed, shedding light on curcumin's binding mechanisms, pharmacological impacts, and therapeutic application in various cancers and inflammatory conditions. These studies are pivotal in understanding curcumin's functionality and its potential as a therapeutic agent. Conclusively, this review emphasizes the therapeutic promise of curcumin in treating a wide range of health issues, attributed to its complex chemistry and broad pharmacological properties. The research points towards curcumin's growing importance as a multi-faceted natural compound in the medical and scientific community.

Inflammation in Hypervolemic Hemodialysis Patients: The Roles of RelB and Caspase-4

Hypervolemia is associated with inflammation in hemodialysis (HD) patients. How hypervolemia triggers inflammation is not entirely known. We initiated a cross-sectional study enrolling 40 hemodialysis patients who were categorized into normovolemic (N; 23) and hypervolemic (H; 17) groups by bioimpedance measurement. A caspase activity assay in combination with a specific caspase-4 inhibitor was used to detect caspase-4 activity in isolated peripheral blood mononuclear cells (PBMCs). Transcription factors RelA (pS529) and RelB (pS552) were analyzed by phospho-flow cytometry. Serum endotoxins were detected by an amebocyte lysate-based assay, and IL-6 (interleukin-6) and TNF-α (Tumor necrosis factor-α) gene expression were detected using the ELISA technique. Hypervolemic patients were older, more frequently had diabetes and showed increased CRP and IL-6 levels. Caspase-4 activity, which is linked to intracellular endotoxin detection, was significantly elevated in H patients. While the frequency of RelA-expressing immune cells and the expression density in these cells did not differ, the monocytic frequency of cells positively stained for RelB (pS552) was significantly decreased in H patients. Increased caspase-4 activity in H patients may indicate a cause of inflammation in H patients. The post-translational modification of RelB (pS552) is linked to downregulation of NF-kB activity and may indicate the resolution of inflammation, which is more distinct in N patients compared to H patients. Therefore, both higher inflammatory loads and lower inflammatory resolution capacities are characteristics of H patients.

CK2β Regulates Hematopoietic Stem Cell Biology and Erythropoiesis

The Ser-Thr kinase CK2 plays important roles in sustaining cell survival and resistance to stress and these functions are exploited by different types of blood tumors. Yet, the physiological involvement of CK2 in normal blood cell development is poorly known. Here, we discovered that the β regulatory subunit of CK2 is critical for normal hematopoiesis in the mouse. Fetal livers of conditional CK2β knockout embryos showed increased numbers of hematopoietic stem cells associated to a higher proliferation rate compared to control animals. Both hematopoietic stem and progenitor cells (HSPCs) displayed alterations in the expression of transcription factors involved in cell quiescence, self-renewal, and lineage commitment. HSPCs lacking CK2β were functionally impaired in supporting both in vitro and in vivo hematopoiesis as demonstrated by transplantation assays. Furthermore, KO mice developed anemia due to a reduced number of mature erythroid cells. This compartment was characterized by dysplasia, proliferative defects at early precursor stage, and apoptosis at late-stage erythroblasts. Erythroid cells exhibited a marked compromise of signaling cascades downstream of the cKit and erythropoietin receptor, with a defective activation of ERK/JNK, JAK/STAT5, and PI3K/AKT pathways and perturbations of several transcriptional programs as demonstrated by RNA-Seq analysis. Moreover, we unraveled an unforeseen molecular mechanism whereby CK2 sustains GATA1 stability and transcriptional proficiency. Thus, our work demonstrates new and crucial functions of CK2 in HSPC biology and in erythropoiesis.

Inhibition of CK2/ING4 Pathway Facilitates Non-Small Cell Lung Cancer Immunotherapy

Immune cells can protect against tumor progression by killing cancer cells, while aberrant expression of the immune checkpoint protein PD-L1 (programmed death ligand 1) in cancer cells facilitates tumor immune escape and inhibits anti-tumor immunotherapy. As a serine/threonine kinase, CK2 (casein kinase 2) regulates tumor progression by multiple pathways, while it is still unclear the effect of CK2 on tumor immune escape. Here it is found that ING4 induced PD-L1 autophagic degradation and inhibites non-small cell lung cancer (NSCLC) immune escape by increasing T cell activity. However, clinical analysis suggests that high expression of CK2 correlates with low ING4 protein level in NSCLC. Further analysis shows that CK2 induce ING4-S150 phosphorylation leading to ING4 ubiquitination and degradation by JFK ubiquitin ligase. In contrast, CK2 gene knockout increases ING4 protein stability and T cell activity, subsequently, inhibites NSCLC immune escape. Furthermore, the combined CK2 inhibitor with PD-1 antibody effectively enhances antitumor immunotherapy. These findings provide a novel strategy for cancer immunotherapy.

Formulation and Investigation of CK2 Inhibitor-Loaded Alginate Microbeads with Different Excipients

The aim of this study was to formulate and characterize CK2 inhibitor-loaded alginate microbeads via the polymerization method. Different excipients were used in the formulation to improve the penetration of an active agent and to stabilize our preparations. Transcutol® HP was added to the drug-sodium alginate mixture and polyvinylpyrrolidone (PVP) was added to the hardening solution, alone and in combination. To characterize the formulations, mean particle size, scanning electron microscopy analysis, encapsulation efficiency, swelling behavior, an enzymatic stability test and an in vitro dissolution study were performed. The cell viability assay and permeability test were also carried out on the Caco-2 cell line. The anti-oxidant and anti-inflammatory effects of the formulations were finally evaluated. The combination of Transcutol® HP and PVP in the formulation of sodium alginate microbeads could improve the stability, in vitro permeability, anti-oxidant and anti-inflammatory effects of the CK2 inhibitor.

NF-κB and STAT3 activation in CD4 T cells in pediatric MOG antibody-associated disease

In this study, we examined CD4 T cell activation using various stimuli in pediatric MOGAD patients (n = 4, untreated remission samples) and healthy controls (n = 5), to understand how both antigen-specific and bystander mechanisms contribute to CD4 T cell activation in MOGAD. TNFα, IL6, and MOG peptide pool were found to activate NF-κB or STAT3 pathways by measuring the expression of regulators (A20, IκBα) and phosphorylated subunits (phospho-p65 and phospho-STAT3) using immunolabeling. Prednisolone reversed activation of both NF-κB and STAT3 and increased the expression of A20 and IκBα. TNFR blocking partially reversed NF-κB activation in certain CD4 T cell subsets, but did not effect STAT3 activation. We observed that activation of NF-κB and STAT3 in response to various stimuli behaves mostly same in MOGAD (remission) and HC. IL6 stimulation resulted in higher STAT3 phosphorylation in MOGAD patients at 75 min, specifically in central and effector memory CD4 T cells (with unadjusted p-values). These findings suggest the potential therapeutic targeting of NF-κB and STAT3 pathways in MOGAD. Further investigation is needed to validate the significance of extended STAT3 phosphorylation and its correlation with IL6 receptor blocker treatment response.

CSNK2A2 promotes hepatocellular carcinoma progression through activation of NF-κB pathway

INTRODUCTION AND OBJECTIVES

Breast and non-small cell lung cancers harbor an upregulated CSNK2A2 oncogene that encodes the protein kinase CK2 alpha', a catalytic subunit of the highly conserved serine/threonine kinase CK2. However, its role and biological significance in hepatocellular carcinoma (HCC) remains unclear.

MATERIALS AND METHODS

Western-blotting and immunohistochemistry were used to measure the expression of CSNK2A2 in HCC tumor tissues and cell lines. CCK8, Hoechst staining, transwell, tube formation assay in vitro and nude mice experiments in vivo were used to measure the effects of CSNK2A2 on HCC proliferation, apoptosis, metastasis, angiogenesis and tumor formation.

RESULTS

In the study, we showed that CSNK2A2 was highly expressed in HCC comparison with matched control tissues, and was linked with lower survival of patients. Additional experiments indicated that silencing of CSNK2A2 promoted HCC cell apoptosis, while inhibited HCC cells migrating, proliferating, angiogenesis both in vitro and in vivo. These effects were also accompanied by reduced expression of NF-κB target genes, including CCND1, MMP9 and VEGF. Moreover, treatment with PDTC counteracted the promotional effects of CSNK2A2 on HCC cells.

CONCLUSIONS

Overall, our results suggested that CSNK2A2 could promote HCC progression by activating the NF-κB pathway, and this could serve as a biomarker for future prognostic and therapeutic applications.

Casein Kinase 2 (CK2): A Possible Therapeutic Target in Acute Myeloid Leukemia

The protein kinase CK2 (also known as casein kinase 2) is one of the main contributors to the human phosphoproteome. It is regarded as a possible therapeutic strategy in several malignant diseases, including acute myeloid leukemia (AML), which is an aggressive bone marrow malignancy. CK2 is an important regulator of intracellular signaling in AML cells, especially PI3K-Akt, Jak-Stat, NFκB, Wnt, and DNA repair signaling. High CK2 levels in AML cells at the first time of diagnosis are associated with decreased survival (i.e., increased risk of chemoresistant leukemia relapse) for patients receiving intensive and potentially curative antileukemic therapy. However, it is not known whether these high CK2 levels can be used as an independent prognostic biomarker because this has not been investigated in multivariate analyses. Several CK2 inhibitors have been developed, but CX-4945/silmitasertib is best characterized. This drug has antiproliferative and proapoptotic effects in primary human AML cells. The preliminary results from studies of silmitasertib in the treatment of other malignancies suggest that gastrointestinal and bone marrow toxicities are relatively common. However, clinical AML studies are not available. Taken together, the available experimental and clinical evidence suggests that the possible use of CK2 inhibition in the treatment of AML should be further investigated.

Structure-guided discovery of adenosine triphosphate-competitive casein kinase 2 inhibitors

Casein kinase 2 (CK2) is a ubiquitous, highly pleiotropic serine-threonine kinase. CK2 has been identified as a potential drug target for the treatment of cancer and related disorders. Several adenosine triphosphate-competitive CK2 inhibitors have been identified and have progressed at different levels of clinical trials. This review presents details of CK2 protein, structural insights into adenosine triphosphate binding pocket, current clinical trial candidates and their analogues. Further, it includes the emerging structure-based drug design approaches, chemistry, structure-activity relationship and biological screening of potent and selective CK2 inhibitors. The authors tabulated the details of CK2 co-crystal structures because these co-crystal structures facilitated the structure-guided discovery of CK2 inhibitors. The narrow hinge pocket compared with related kinases provides useful insights into the discovery of CK2 inhibitors.

Distinct Roles of CK2- and AKT-Mediated NF-κB Phosphorylations in Clasmatodendrosis (Autophagic Astroglial Death) within the Hippocampus of Chronic Epilepsy Rats

The downregulation of glutathione peroxidase-1 (GPx1) plays a role in clasmatodendrosis (an autophagic astroglial death) in the hippocampus of chronic epilepsy rats. Furthermore, N-acetylcysteine (NAC, a GSH precursor) restores GPx1 expression in clasmatodendritic astrocytes and alleviates this autophagic astroglial death, independent of nuclear factor erythroid-2-related factor 2 (Nrf2) activity. However, the regulatory signal pathways of these phenomena have not been fully explored. In the present study, NAC attenuated clasmatodendrosis by alleviating GPx1 downregulation, casein kinase 2 (CK2)-mediated nuclear factor-κB (NF-κB) serine (S) 529 and AKT-mediated NF-κB S536 phosphorylations. 2-[4,5,6,7-Tetrabromo-2-(dimethylamino)-1H-benzo[d]imidazole-1-yl]acetic acid (TMCB; a selective CK2 inhibitor) relieved clasmatodendritic degeneration and GPx1 downregulation concomitant with the decreased NF-κB S529 and AKT S473 phosphorylations. In contrast, AKT inhibition by 3-chloroacetyl-indole (3CAI) ameliorated clasmatodendrosis and NF-κB S536 phosphorylation, while it did not affect GPx1 downregulation and CK2 tyrosine (Y) 255 and NF-κB S529 phosphorylations. Therefore, these findings suggest that seizure-induced oxidative stress may diminish GPx1 expression by increasing CK2-mediated NF-κB S529 phosphorylation, which would subsequently enhance AKT-mediated NF-κB S536 phosphorylation leading to autophagic astroglial degeneration.

The role of HDAC3 and its inhibitors in regulation of oxidative stress and chronic diseases

HDAC3 is a specific and crucial member of the HDAC family. It is required for embryonic growth, development, and physiological function. The regulation of oxidative stress is an important factor in intracellular homeostasis and signal transduction. Currently, HDAC3 has been found to regulate several oxidative stress-related processes and molecules dependent on its deacetylase and non-enzymatic activities. In this review, we comprehensively summarize the knowledge of the relationship of HDAC3 with mitochondria function and metabolism, ROS-produced enzymes, antioxidant enzymes, and oxidative stress-associated transcription factors. We also discuss the role of HDAC3 and its inhibitors in some chronic cardiovascular, kidney, and neurodegenerative diseases. Due to the simultaneous existence of enzyme activity and non-enzyme activity, HDAC3 and the development of its selective inhibitors still need further exploration in the future.

Purple Sweet Potato Powder Containing Anthocyanin Mitigates High-Fat-Diet-Induced Dry Eye Disease

Purple sweet potato (PSP) powder with anthocyanins possesses the ability to reduce oxidative stress and inflammation. Studies have presumed a positive correlation between body fat and dry eye disease (DED) in adults. The regulation of oxidative stress and inflammation has been proposed as the mechanism underlying DED. This study developed an animal model of high fat diet (HFD)-induced DED. We added 5% PSP powder to the HFD to evaluate the effects and underlying mechanisms in mitigating HFD-induced DED. A statin drug, atorvastatin, was also added to the diet separately to assess its effect. The HFD altered the structure of lacrimal gland (LG) tissue, reduced LG secretory function, and eliminated the expression of proteins related to DED development, including α-smooth muscle actin and aquaporin-5. Although PSP treatment could not significantly reduce body weight or body fat, it ameliorated the effects of DED by preserving LG secretory function, preventing ocular surface erosion, and preserving LG structure. PSP treatment increased superoxide dismutase levels but reduced hypoxia-inducible factor 1-α levels, indicating that PSP treatment reduced oxidative stress. PSP treatment increased ATP-binding cassette transporter 1 and acetyl-CoA carboxylase 1 levels in LG tissue, signifying that PSP treatment regulated lipid homeostasis maintenance to reduce the effects of DED. In conclusion, PSP treatment ameliorated the effects of HFD-induced DED through the regulation of oxidative stress and lipid homeostasis in the LG.

CDDO-Me Abrogates Aberrant Mitochondrial Elongation in Clasmatodendritic Degeneration by Regulating NF-κB-PDI-Mediated S-Nitrosylation of DRP1

Clasmatodendrosis is a kind of astroglial degeneration pattern which facilitates excessive autophagy. Although abnormal mitochondrial elongation is relevant to this astroglial degeneration, the underlying mechanisms of aberrant mitochondrial dynamics are still incompletely understood. Protein disulfide isomerase (PDI) is an oxidoreductase in the endoplasmic reticulum (ER). Since PDI expression is downregulated in clasmatodendritic astrocytes, PDI may be involved in aberrant mitochondrial elongation in clasmatodendritic astrocytes. In the present study, 26% of CA1 astrocytes showed clasmatodendritic degeneration in chronic epilepsy rats. 2-cyano-3,12-dioxo-oleana-1,9(11)-dien-28-oic acid methyl ester (CDDO-Me; bardoxolone methyl or RTA 402) and SN50 (a nuclear factor-κB (NF-κB) inhibitor) ameliorated the fraction of clasmatodendritic astrocytes to 6.8 and 8.1% in CA1 astrocytes, accompanied by the decreases in lysosomal-associated membrane protein 1 (LAMP1) expression and microtubule-associated protein 1A/1B light-chain 3 (LC3)-II/LC3-I ratio, indicating the reduced autophagy flux. Furthermore, CDDO-Me and SN50 reduced NF-κB S529 fluorescent intensity to 0.6- and 0.57-fold of vehicle-treated animal level, respectively. CDDO-Me and SN50 facilitated mitochondrial fission in CA1 astrocytes, independent of dynamin-related protein 1 (DRP1) S616 phosphorylation. In chronic epilepsy rats, total PDI protein, S-nitrosylated PDI (SNO-PDI), and SNO-DRP1 levels were 0.35-, 0.34- and 0.45-fold of control level, respectively, in the CA1 region and increased CDDO-Me and SN50. Furthermore, PDI knockdown resulted in mitochondrial elongation in intact CA1 astrocytes under physiological condition, while it did not evoke clasmatodendrosis. Therefore, our findings suggest that NF-κB-mediated PDI inhibition may play an important role in clasmatodendrosis via aberrant mitochondrial elongation.

Protein Kinase CK2 and Epstein-Barr Virus

Protein kinase CK2 is a pleiotropic protein kinase, which phosphorylates a number of cellular and viral proteins. Thereby, this kinase is implicated in the regulation of cellular signaling, controlling of cell proliferation, apoptosis, angiogenesis, immune response, migration and invasion. In general, viruses use host signaling mechanisms for the replication of their genome as well as for cell transformation leading to cancer. Therefore, it is not surprising that CK2 also plays a role in controlling viral infection and the generation of cancer cells. Epstein-Barr virus (EBV) lytically infects epithelial cells of the oropharynx and B cells. These latently infected B cells subsequently become resting memory B cells when passing the germinal center. Importantly, EBV is responsible for the generation of tumors such as Burkitt's lymphoma. EBV was one of the first human viruses, which was connected to CK2 in the early nineties of the last century. The present review shows that protein kinase CK2 phosphorylates EBV encoded proteins as well as cellular proteins, which are implicated in the lytic and persistent infection and in EBV-induced neoplastic transformation. EBV-encoded and CK2-phosphorylated proteins together with CK2-phosphorylated cellular signaling proteins have the potential to provide efficient virus replication and cell transformation. Since there are powerful inhibitors known for CK2 kinase activity, CK2 might become an attractive target for the inhibition of EBV replication and cell transformation.

Protein Kinase CK2 Contributes to Glucose Homeostasis by Targeting Fructose-1,6-Bisphosphatase 1

Glucose homeostasis is of critical importance for the survival of organisms. It is under hormonal control and often coordinated by the action of kinases and phosphatases. We have previously shown that CK2 regulates insulin production and secretion in pancreatic β-cells. In order to shed more light on the CK2-regulated network of glucose homeostasis, in the present study, a qRT-PCR array was carried out with 84 diabetes-associated genes. After inhibition of CK2, fructose-1,6-bisphosphatase 1 (FBP1) showed a significant lower gene expression. Moreover, FBP1 activity was down-regulated. Being a central enzyme of gluconeogenesis, the secretion of glucose was decreased as well. Thus, FBP1 is a new factor in the CK2-regulated network implicated in carbohydrate metabolism control.

Therapeutic Targeting of NF-κB in Acute Lung Injury: A Double-Edged Sword

Acute lung injury/acute respiratory distress syndrome (ALI/ARDS) is a devastating disease that can be caused by a variety of conditions including pneumonia, sepsis, trauma, and most recently, COVID-19. Although our understanding of the mechanisms of ALI/ARDS pathogenesis and resolution has considerably increased in recent years, the mortality rate remains unacceptably high (~40%), primarily due to the lack of effective therapies for ALI/ARDS. Dysregulated inflammation, as characterized by massive infiltration of polymorphonuclear leukocytes (PMNs) into the airspace and the associated damage of the capillary-alveolar barrier leading to pulmonary edema and hypoxemia, is a major hallmark of ALI/ARDS. Endothelial cells (ECs), the inner lining of blood vessels, are important cellular orchestrators of PMN infiltration in the lung. Nuclear factor-kappa B (NF-κB) plays an essential role in rendering the endothelium permissive for PMN adhesion and transmigration to reach the inflammatory site. Thus, targeting NF-κB in the endothelium provides an attractive approach to mitigate PMN-mediated vascular injury, not only in ALI/ARDS, but in other inflammatory diseases as well in which EC dysfunction is a major pathogenic mechanism. This review discusses the role and regulation of NF-κB in the context of EC inflammation and evaluates the potential and problems of targeting it as a therapy for ALI/ARDS.

CK2 and the Hallmarks of Cancer

Cancer is a leading cause of death worldwide. Casein kinase 2 (CK2) is commonly dysregulated in cancer, impacting diverse molecular pathways. CK2 is a highly conserved serine/threonine kinase, constitutively active and ubiquitously expressed in eukaryotes. With over 500 known substrates and being estimated to be responsible for up to 10% of the human phosphoproteome, it is of significant importance. A broad spectrum of diverse types of cancer cells has been already shown to rely on disturbed CK2 levels for their survival. The hallmarks of cancer provide a rationale for understanding cancer's common traits. They constitute the maintenance of proliferative signaling, evasion of growth suppressors, resisting cell death, enabling of replicative immortality, induction of angiogenesis, the activation of invasion and metastasis, as well as avoidance of immune destruction and dysregulation of cellular energetics. In this work, we have compiled evidence from the literature suggesting that CK2 modulates all hallmarks of cancer, thereby promoting oncogenesis and operating as a cancer driver by creating a cellular environment favorable to neoplasia.

Protein Kinase CK2 represents a new target to boost Ibrutinib and Venetoclax induced cytotoxicity in mantle cell lymphoma

Mantle cell lymphoma (MCL) is an incurable B cell non-Hodgkin lymphoma, characterized by frequent relapses. In the last decade, the pro-survival pathways related to BCR signaling and Bcl-2 have been considered rational therapeutic targets in B cell derived lymphomas. The BTK inhibitor Ibrutinib and the Bcl-2 inhibitor Venetoclax are emerging as effective drugs for MCL. However, primary and acquired resistance also to these agents may occur. Protein Kinase CK2 is a S/T kinase overexpressed in many solid and blood-derived tumours. CK2 promotes cancer cell growth and clonal expansion, sustaining pivotal survival signaling cascades, such as the ones dependent on AKT, NF-κB, STAT3 and others, counteracting apoptosis through a “non-oncogene” addiction mechanism. We previously showed that CK2 is overexpressed in MCL and regulates the levels of activating phosphorylation on S529 of the NF-κB family member p65/RelA. In the present study, we investigated the effects of CK2 inactivation on MCL cell proliferation, survival and apoptosis and this kinase’s involvement in the BCR and Bcl-2 related signaling. By employing CK2 loss of function MCL cell models, we demonstrated that CK2 sustains BCR signaling (such as BTK, NF-κB and AKT) and the Bcl-2-related Mcl-1 expression. CK2 inactivation enhanced Ibrutinib and Venetoclax-induced cytotoxicity. The demonstration of a CK2-dependent upregulation of pathways that may antagonize the effect of these drugs may offer a novel strategy to overcome primary and secondary resistance.

The Role of Protein Kinase CK2 in Development and Disease Progression: A Critical Review

Protein kinase CK2 (CK2) is a ubiquitous holoenzyme involved in a wide array of developmental processes. The involvement of CK2 in events such as neurogenesis, cardiogenesis, skeletogenesis, and spermatogenesis is essential for the viability of almost all organisms, and its role has been conserved throughout evolution. Further into adulthood, CK2 continues to function as a key regulator of pathways affecting crucial processes such as osteogenesis, adipogenesis, chondrogenesis, neuron differentiation, and the immune response. Due to its vast role in a multitude of pathways, aberrant functioning of this kinase leads to embryonic lethality and numerous diseases and disorders, including cancer and neurological disorders. As a result, CK2 is a popular target for interventions aiming to treat the aforementioned diseases. Specifically, two CK2 inhibitors, namely CX-4945 and CIBG-300, are in the early stages of clinical testing and exhibit promise for treating cancer and other disorders. Further, other researchers around the world are focusing on CK2 to treat bone disorders. This review summarizes the current understanding of CK2 in development, the structure of CK2, the targets and signaling pathways of CK2, the implication of CK2 in disease progression, and the recent therapeutics developed to inhibit the dysregulation of CK2 function in various diseases.

Theragnostic strategies harnessing the self-renewal pathways of stem-like cells in the acute myeloid leukemia

Acute myelogenous leukemia (AML) is a genetically heterogeneous and aggressive cancer of the Hematopoietic Stem/progenitor cells. It is distinguished by the uncontrollable clonal growth of malignant myeloid stem cells in the bone marrow, venous blood, and other body tissues. AML is the most predominant of leukemias occurring in adults (25%) and children (15-20%). The relapse after chemotherapy is a major concern in the treatment of AML. The overall 5-year survival rate in young AML patients is about 40-45% whereas in the elderly patients it is less than 10%. Leukemia stem-like cells (LSCs) having the ability to self-renew indefinitely, repopulate and persist longer in the G0/G1 phase play a crucial role in the AML relapse and refractoriness to chemotherapy. Hence, novel treatment strategies and diagnostic biomarkers targeting LSCs are being increasingly investigated. Through this review, we have explored the signaling modulations in the LSCs as the theragnostic targets. The significance of the self-renewal pathways in overcoming the treatment challenges in AML has been highlighted.

Evaluation of a Selective Chemical Probe Validates That CK2 Mediates Neuroinflammation in a Human Induced Pluripotent Stem Cell-Derived Microglial Model

Novel treatments for neurodegenerative disorders are in high demand. It is imperative that new protein targets be identified to address this need. Characterization and validation of nascent targets can be accomplished very effectively using highly specific and potent chemical probes. Human induced pluripotent stem cells (hiPSCs) provide a relevant platform for testing new compounds in disease relevant cell types. However, many recent studies utilizing this platform have focused on neuronal cells. In this study, we used hiPSC-derived microglia-like cells (MGLs) to perform side-by-side testing of a selective chemical probe, SGC-CK2-1, compared with an advanced clinical candidate, CX-4945, both targeting casein kinase 2 (CK2), one of the first kinases shown to be dysregulated in Alzheimer's disease (AD). CK2 can mediate neuroinflammation in AD, however, its role in microglia, the innate immune cells of the central nervous system (CNS), has not been defined. We analyzed available RNA-seq data to determine the microglial expression of kinases inhibited by SGC-CK2-1 and CX-4945 with a reported role in mediating inflammation in glial cells. As proof-of-concept for using hiPSC-MGLs as a potential screening platform, we used both wild-type (WT) MGLs and MGLs harboring a mutation in presenilin-1 (PSEN1), which is causative for early-onset, familial AD (FAD). We stimulated these MGLs with pro-inflammatory lipopolysaccharides (LPS) derived from E. coli and observed strong inhibition of the expression and secretion of proinflammatory cytokines by simultaneous treatment with SGC-CK2-1. A direct comparison shows that SGC-CK2-1 was more effective at suppression of proinflammatory cytokines than CX-4945. Together, these results validate a selective chemical probe, SGC-CK2-1, in human microglia as a tool to reduce neuroinflammation.

The Emerging Role of OTUB2 in Diseases: From Cell Signaling Pathway to Physiological Function

Ovarian tumor (OTU) domain-containing ubiquitin aldehyde-binding protein Otubain2 (OTUB2) was a functional cysteine protease in the OTU family with deubiquitinase activity. In recent years, with the wide application of molecular biology techniques, molecular mechanism regulation at multiple levels of cell signaling pathways has been gradually known, such as ubiquitin-mediated protein degradation and phosphorylation-mediated protein activation. OTUB2 is involved in the deubiquitination of many key proteins in different cell signaling pathways, and the effect of OTUB2 on human health or disease is not clear. OTUB2 is likely to cause cancer and other malignant diseases while maintaining normal human development and physiological function. Therefore, it is of great value to comprehensively understand the regulatory mechanism of OTUB2 and regard it as a target for the treatment of diseases. This review makes a general description and appropriate analysis of OTUB2's regulation in different cell signaling pathways, and connects OTUB2 with cancer from the research hotspot perspective of DNA damage repair and immunity, laying the theoretical foundation for future research.

The Immune Underpinnings of Barrett's-Associated Adenocarcinogenesis: a Retrial of Nefarious Immunologic Co-Conspirators

There is no doubt that chronic gastroesophageal reflux disease increases the risk of esophageal adenocarcinoma (EAC) by several fold (odds ratio, 6.4; 95% CI, 4.6-9.1), and some relationships between reflux disease-mediated inflammation and oncogenic processes have been explored; however, the precise interconnections between the immune response and genomic instabilities underlying these pathologic processes only now are emerging. Furthermore, the precise cell of origin of the precancerous stages associated with EAC development, Barrett's esophagus, be it cardia resident or embryonic remnant, may shape our interpretation of the likely immune drivers. This review integrates the current collective knowledge of the immunology underlying EAC development and outlines a framework connecting proinflammatory pathways, such as those mediated by interleukin 1β, tumor necrosis factor α, leukemia inhibitory factor, interleukin 6, signal transduction and activator of transcription 3, nuclear factor-κB, cyclooxygenase-2, and transforming growth factor β, with oncogenic pathways in the gastroesophageal reflux disease-Barrett's esophagus-EAC cancer sequence. Further defining these immune and molecular railroads may show a map of the routes taken by gastroesophageal cells on their journey toward EAC tumor phylogeny. The selective pressures applied by this immune-induced journey likely impact the phenotype and genotype of the resulting oncogenic destination and further exploration of lesser-defined immune drivers may be useful in future individualized therapies or enhanced selective application of recent immune-driven therapeutics.

IL-1β promotes IL-9-producing Th cell differentiation in IL-2-limiting conditions through the inhibition of BCL6

IL-9-producing CD4⁺ T helper cells, termed Th9 cells, differentiate from naïve precursor cells in response to a combination of cytokine and cell surface receptor signals that are elevated in inflamed tissues. After differentiation, Th9 cells accumulate in these tissues where they exacerbate allergic and intestinal disease or enhance anti-parasite and anti-tumor immunity. Previous work indicates that the differentiation of Th9 cells requires the inflammatory cytokines IL-4 and TGF-β and is also dependent of the T cell growth factor IL-2. While the roles of IL-4 and TGF-β-mediated signaling are relatively well understood, how IL-2 signaling contributes to Th9 cell differentiation outside of directly inducing the Il9 locus remains less clear. We show here that murine Th9 cells that differentiate in IL-2-limiting conditions exhibit reduced IL-9 production, diminished NF-kB activation and a reduced NF-kB-associated transcriptional signature, suggesting that IL-2 signaling is required for optimal NF-kB activation in Th9 cells. Interestingly, both IL-9 production and the NF-kB transcriptional signature could be rescued by addition of the NF-kB-activating cytokine IL-1β to IL-2-limiting cultures. IL-1β was unique among NF-kB-activating factors in its ability to rescue Th9 differentiation as IL-2 deprived Th9 cells selectively induced IL-1R expression and IL-1β/IL-1R1 signaling enhanced the sensitivity of Th9 cells to limiting amounts of IL-2 by suppressing expression of the Th9 inhibitory factor BCL6. These data shed new light on the intertwined nature of IL-2 and NF-kB signaling pathways in differentiating Th cells and elucidate the potential mechanisms that promote Th9 inflammatory function in IL-2-limiting conditions.

The Immune Regulatory Role of Protein Kinase CK2 and Its Implications for Treatment of Cancer

Protein Kinase CK2, a constitutively active serine/threonine kinase, fulfills its functions via phosphorylating hundreds of proteins in nearly all cells. It regulates a variety of cellular signaling pathways and contributes to cell survival, proliferation and inflammation. CK2 has been implicated in the pathogenesis of hematologic and solid cancers. Recent data have documented that CK2 has unique functions in both innate and adaptive immune cells. In this article, we review aspects of CK2 biology, functions of the major innate and adaptive immune cells, and how CK2 regulates the function of immune cells. Finally, we provide perspectives on how CK2 effects in immune cells, particularly T-cells, may impact the treatment of cancers via targeting CK2.

Simultaneous CK2/TNIK/DYRK1 inhibition by 108600 suppresses triple negative breast cancer stem cells and chemotherapy-resistant disease

Triple negative breast cancer (TNBC) remains challenging because of heterogeneous responses to chemotherapy. Incomplete response is associated with a greater risk of metastatic progression. Therefore, treatments that target chemotherapy-resistant TNBC and enhance chemosensitivity would improve outcomes for these high-risk patients. Breast cancer stem cell-like cells (BCSCs) have been proposed to represent a chemotherapy-resistant subpopulation responsible for tumor initiation, progression and metastases. Targeting this population could lead to improved TNBC disease control. Here, we describe a novel multi-kinase inhibitor, 108600, that targets the TNBC BCSC population. 108600 treatment suppresses growth, colony and mammosphere forming capacity of BCSCs and induces G2M arrest and apoptosis of TNBC cells. In vivo, 108600 treatment of mice bearing triple negative tumors results in the induction of apoptosis and overcomes chemotherapy resistance. Finally, treatment with 108600 and chemotherapy suppresses growth of pre-established TNBC metastases, providing additional support for the clinical translation of this agent to clinical trials.

Does oxidatively damaged DNA drive amyloid-β generation in Alzheimer's disease? A hypothesis

In Alzheimer's disease (AD), amyloid-β (Aβ) generation and upstream β-secretase 1 (BACE1) expression appear to be driven by oxidative stress via c-Jun N-terminal kinase (JNK), p38, and Interferon-Induced, Double-Stranded RNA-Activated Protein Kinase (PKR). In addition, inflammatory molecules, including lipopolysaccharide (LPS), induce genes central to Aβ genesis, such as BACE1, via nuclear factor-κB (NFκB). However, additional triggers of Aβ generation remain poorly understood and might represent novel opportunities for therapeutic intervention. Based on mechanistic studies and elevated ectopic oxidatively damaged DNA (oxoDNA) levels in preclinical AD, mild cognitive impairment, and AD patients, we hypothesize oxoDNA contributes to β-amyloidosis starting from the earliest stages of AD through multiple pathways. OxoDNA induces mitogen-activated protein kinase kinase kinase kinase 4 (MAP4K4), thereby sensitizing the brain to oxidative stress-induced JNK activation and BACE1 transcription. It also induces myeloid differentiation primary response 88 (MyD88) and activates protein kinase CK2, thereby increasing NFκB activation and BACE1 induction. OxoDNA increases oxidative stress via nuclear factor erythroid 2-related factor 2 (Nrf2) ectopic localization, likely augmenting JNK-mediated BACE1 induction. OxoDNA likely also promotes β-amyloidosis via absent in melanoma 2 (AIM2) induction. Falsifiable predictions of this hypothesis include that deoxyribonuclease treatment should decrease Aβ and possibly slow cognitive decline in AD patients. While formal testing of this hypothesis remains to be performed, a case report has found deoxyribonuclease I treatment improved a severely demented AD patient's Mini-Mental Status Exam score from 3 to 18 at 2 months. There is preliminary preclinical and clinical evidence suggesting that ectopic oxidatively damaged DNA may act as an inflammatory damage-associated molecular pattern contributing to Aβ generation in AD, and deoxyribonuclease I should be formally evaluated to test whether it can decrease Aβ levels and slow cognitive decline in AD patients.

Targeting Immune Modulators in Glioma While Avoiding Autoimmune Conditions

Communication signals and signaling pathways are often studied in different physiological systems. However, it has become abundantly clear that the immune system is not self-regulated, but functions in close association with the nervous system. The neural-immune interface is complex; its balance determines cancer progression, as well as autoimmune disorders. Immunotherapy remains a promising approach in the context of glioblastoma multiforme (GBM). The primary obstacle to finding effective therapies is the potent immunosuppression induced by GBM. Anti-inflammatory cytokines, induction of regulatory T cells, and the expression of immune checkpoint molecules are the key mediators for immunosuppression in the tumor microenvironment. Immune checkpoint molecules are ligand-receptor pairs that exert inhibitory or stimulatory effects on immune responses. In the past decade, they have been extensively studied in preclinical and clinical trials in diseases such as cancer or autoimmune diseases in which the immune system has failed to maintain homeostasis. In this review, we will discuss promising immune-modulatory targets that are in the focus of current clinical research in glioblastoma, but are also in the precarious position of potentially becoming starting points for the development of autoimmune diseases like multiple sclerosis.

HIPK2 phosphorylates HDAC3 for NF-κB acetylation to ameliorate colitis-associated colorectal carcinoma and sepsis

Although inflammation is critical for the clearance of pathogens, uncontrolled inflammation also contributes to the development of multiple diseases such as cancer and sepsis. Since NF-κB-mediated transactivation in the nucleus is pivotal downstream of various stimuli to induce inflammation, searching the nuclear-localized targets specifically regulating NF-κB activation will provide important therapeutic application. Here, we have identified that homeodomain-interacting protein kinase 2 (HIPK2), a nuclear serine/threonine kinase, increases its expression in inflammatory macrophages. Importantly, HIPK2 deficiency or overexpression could enhance or inhibit inflammatory responses in LPS-stimulated macrophages, respectively. HIPK2-deficient mice were more susceptible to LPS-induced endotoxemia and CLP-induced sepsis. Adoptive transfer of Hipk2+/- bone marrow cells (BMs) also aggravated AOM/DSS-induced colorectal cancer. Mechanistically, HIPK2 bound and phosphorylated histone deacetylase 3 (HDAC3) at serine 374 to inhibit its enzymatic activity, thus reducing the deacetylation of p65 at lysine 218 to suppress NF-κB activation. Notably, the HDAC3 inhibitors protected wild-type or Hipk2-/- BMs-reconstituted mice from LPS-induced endotoxemia. Our findings suggest that the HIPK2-HDAC3-p65 module in macrophages restrains excessive inflammation, which may represent a new layer of therapeutic mechanism for colitis-associated colorectal cancer and sepsis.

CX-4945 and siRNA-Mediated Knockdown of CK2 Improves Cisplatin Response in HPV(+) and HPV(-) HNSCC Cell Lines

Head and neck squamous cell carcinoma (HNSCC) can be categorized into human papillomavirus (HPV) positive or negative disease. Elevated protein kinase CK2 level and activity have been historically observed in HNSCC cells. Previous studies on CK2 in HNSCC did not generally include consideration of HPV(+) and HPV(−) status. Here, we investigated the response of HPV(+) and HPV(−) HNSCC cells to CK2 targeting using CX-4945 or siRNA downregulation combined with cisplatin treatment. HNSCC cell lines were examined for CK2 expression levels and activity and response to CX-4945, with and without cisplatin. CK2 levels and NFκB p65-related activity were high in HPV(+) HNSCC cells relative to HPV(−) HNSCC cells. Treatment with CX-4945 decreased viability and cisplatin IC50 in all cell lines. Targeting of CK2 increased tumor suppressor protein levels for p21 and PDCD4 in most instances. Further study is needed to understand the role of CK2 in HPV(+) and HPV(−) HNSCC and to determine how incorporation of the CK2-targeted inhibitor CX-4945 could improve cisplatin response in HNSCC.

Protein kinase CK2: a potential therapeutic target for diverse human diseases

CK2 is a constitutively active Ser/Thr protein kinase, which phosphorylates hundreds of substrates, controls several signaling pathways, and is implicated in a plethora of human diseases. Its best documented role is in cancer, where it regulates practically all malignant hallmarks. Other well-known functions of CK2 are in human infections; in particular, several viruses exploit host cell CK2 for their life cycle. Very recently, also SARS-CoV-2, the virus responsible for the COVID-19 pandemic, has been found to enhance CK2 activity and to induce the phosphorylation of several CK2 substrates (either viral and host proteins). CK2 is also considered an emerging target for neurological diseases, inflammation and autoimmune disorders, diverse ophthalmic pathologies, diabetes, and obesity. In addition, CK2 activity has been associated with cardiovascular diseases, as cardiac ischemia-reperfusion injury, atherosclerosis, and cardiac hypertrophy. The hypothesis of considering CK2 inhibition for cystic fibrosis therapies has been also entertained for many years. Moreover, psychiatric disorders and syndromes due to CK2 mutations have been recently identified. On these bases, CK2 is emerging as an increasingly attractive target in various fields of human medicine, with the advantage that several very specific and effective inhibitors are already available. Here, we review the literature on CK2 implication in different human pathologies and evaluate its potential as a pharmacological target in the light of the most recent findings.

Targeting Protein Kinases in Blood Cancer: Focusing on CK1α and CK2

Disturbance of protein kinase activity may result in dramatic consequences that often lead to cancer development and progression. In tumors of blood origin, both tyrosine kinases and serine/threonine kinases are altered by different types of mutations, critically regulating cancer hallmarks. CK1α and CK2 are highly conserved, ubiquitously expressed and constitutively active pleiotropic kinases, which participate in multiple biological processes. The involvement of these kinases in solid and blood cancers is well documented. CK1α and CK2 are overactive in multiple myeloma, leukemias and lymphomas. Intriguingly, they are not required to the same degree for the viability of normal cells, corroborating the idea of “druggable” kinases. Different to other kinases, mutations on the gene encoding CK1α and CK2 are rare or not reported. Actually, these two kinases are outside the paradigm of oncogene addiction, since cancer cells’ dependency on these proteins resembles the phenomenon of “non-oncogene” addiction. In this review, we will summarize the general features of CK1α and CK2 and the most relevant oncogenic and stress-related signaling nodes, regulated by kinase phosphorylation, that may lead to tumor progression. Finally, we will report the current data, which support the positioning of these two kinases in the therapeutic scene of hematological cancers.

Dissecting the Regulatory Strategies of NF-κB RelA Target Genes in the Inflammatory Response Reveals Differential Transactivation Logics

Nuclear factor κB (NF-κB) RelA is the potent transcriptional activator of inflammatory response genes. We stringently defined a list of direct RelA target genes by integrating physical (chromatin immunoprecipitation sequencing [ChIP-seq]) and functional (RNA sequencing [RNA-seq] in knockouts) datasets. We then dissected each gene’s regulatory strategy by testing RelA variants in a primary-cell genetic-complementation assay. All endogenous target genes require RelA to make DNA-base-specific contacts, and none are activatable by the DNA binding domain alone. However, endogenous target genes differ widely in how they employ the two transactivation domains. Through model-aided analysis of the dynamic time-course data, we reveal the gene-specific synergy and redundancy of TA1 and TA2. Given that post-translational modifications control TA1 activity and intrinsic affinity for coactivators determines TA2 activity, the differential TA logics suggests context-dependent versus context-independent control of endogenous RelA-target genes. Although some inflammatory initiators appear to require co-stimulatory TA1 activation, inflammatory resolvers are a part of the NF-κB RelA core response.

Ngo et al. developed a genetic complementation system for NF-κB RelA that reveals that NF-κB target-gene selection requires high-affinity RelA binding and transcriptional activation domains for gene induction. The synergistic and redundant functions of two transactivation domains define pro-inflammatory and inflammation-response genes.

The Effect of Neddylation Inhibition on Inflammation-Induced MMP9 Gene Expression in Esophageal Squamous Cell Carcinoma

Inhibition of the protein neddylation process by the small-molecule inhibitor MLN4924 has been recently indicated as a promising direction for cancer treatment. However, the knowledge of all biological consequences of MLN4924 for cancer cells is still incomplete. Here, we report that MLN4924 inhibits tumor necrosis factor-alpha (TNF-α)-induced matrix metalloproteinase 9 (MMP9)-driven cell migration. Using real-time polymerase chain reaction (PCR) and gelatin zymography, we found that MLN4924 inhibited expression and activity of MMP9 at the messenger RNA (mRNA) and protein levels in both resting cells and cells stimulated with TNF-α, and this inhibition was closely related to impaired cell migration. We also revealed that MLN4924, similar to TNF-α, induced phosphorylation of inhibitor of nuclear factor kappa B-alpha (IκB-α). However, contrary to TNF-α, MLN4924 did not induce IκB-α degradation in treated cells. In coimmunoprecipitation experiments, nuclear IκB-α which formed complexes with nuclear factor kappa B p65 subunit (NFκB/p65) was found to be highly phosphorylated at Ser32 in the cells treated with MLN4924, but not in the cells treated with TNF-α alone. Moreover, in the presence of MLN4924, nuclear NFκB/p65 complexes were found to be enriched in c-Jun and cyclin dependent kinase inhibitor 1 A (CDKN1A/p21) proteins. In these cells, NFκB/p65 was unable to bind to the MMP9 gene promoter, which was confirmed by the chromatin immunoprecipitation (ChIP) assay. Taken together, our findings identified MLN4924 as a suppressor of TNF-α-induced MMP9-driven cell migration in esophageal squamous cell carcinoma (ESCC), likely acting by affecting the nuclear ubiquitin–proteasome system that governs NFκB/p65 complex formation and its DNA binding activity in regard to the MMP9 promoter, suggesting that inhibition of neddylation might be a new therapeutic strategy to prevent invasion/metastasis in ESCC patients.

CK2 Down-Regulation Increases the Expression of Senescence-Associated Secretory Phenotype Factors through NF-κB Activation

Senescent cells secrete pro-inflammatory factors, and a hallmark feature of senescence is senescence-associated secretory phenotype (SASP). The aim of this study is to investigate the protein kinase CK2 (CK2) effects on SASP factors expression in cellular senescence and organism aging. Here CK2 down-regulation induced the expression of SASP factors, including interleukin (IL)-1β, IL-6, and matrix metalloproteinase (MMP) 3, through the activation of nuclear factor-κB (NF-κB) signaling in MCF-7 and HCT116 cells. CK2 down-regulation-mediated SIRT1 inactivation promoted the degradation of inhibitors of NF-κB (IκB) by activating the AKT-IκB kinase (IKK) axis and increased the acetylation of lysine 310 on RelA/p65, an important site for the activity of NF-κB. kin-10 (the ortholog of CK2β) knockdown increased zmp-1, -2, and -3 (the orthologs of MMP) expression in nematodes, but AKT inhibitor triciribine and SIRT activator resveratrol significantly abrogated the increased expression of these genes. Finally, antisense inhibitors of miR-186, miR-216b, miR-337-3p, and miR-760 suppressed CK2α down-regulation, activation of the AKT-IKK-NF-κB axis, RelA/p65 acetylation, and expression of SASP genes in cells treated with lipopolysaccharide. Therefore, this study indicated that CK2 down-regulation induces the expression of SASP factors through NF-κB activation, which is mediated by both activation of the SIRT1-AKT-IKK axis and RelA/p65 acetylation, suggesting that the mixture of the four miRNA inhibitors can be used as anti-inflammatory agents.