Phosphatase Wip1 in Immunity: An Overview and Update

Wip1 regulates wound healing by affecting activities of keratinocytes and endothelial cells through ATM-p53 and mTOR signaling

BACKGROUND

As a p53-regulated gene, Wip1 regulates proliferation, migration, apoptosis, and senescence of several type cells, but its biological functions in keratinocytes and endothelial cells which are involved wound healing are not fully understood. This study aims to reveal the function and underlying mechanism of Wip1 in wound healing using models of transgenic animal, keratinocytes, and endothelial cells.

METHODS

Using Wip1 knockout C57 BL/6 mice, we investigated effect of Wip1 deficiency on wound healing and angiogenesis; And using HaCaT and HUVEC as keratinocytes and endothelial cells, combined using primary keratinocytes from Wip1 knockout mice, we studied the effects of Wip1 knockdown/knockout or overexpression on proliferation, migration, and protein expressions of signaling components in ATM-p53 and mTOR pathway.

RESULTS

Wip1 deficiency in mice impaired the wound repair and endothelial angiogenesis, reduced the thickness of granulation tissue, and decreased the number of Ki67-positive cells and CD31 positive vessels in granulation tissue. Knockdown of Wip1 by shRNAs suppressed the proliferation and migration of HaCaT and HUVEC cells and induced notably apoptosis in the two cells. In western blot, Wip1 knockdown enriched p53 and ATM proteins, while decreased activated AKT, mTOR and activated S6 ribosomal protein (pS6) levels in HaCaT and HUVEC cells. Ectopic expression of Wip1 decreased the p53 and ATM proteins, while increased activated AKT, mTOR and pS6 levels in HaCaT and HUVEC cells. And in primary keratinocytes from mice tail skin, Wip1 knockout increased p53 and ATM, while decreased activated AKT, mTOR and pS6 protein levels.

CONCLUSION

Our study directly supports that Wip1 regulated skin wound healing possibly by affecting bioactivities including proliferation, migration and apoptosis of keratinocytes and endothelial cells at least through by modulating ATM-p53 and mTOR signaling.

Targeting p53 for neuroinflammation: New therapeutic strategies in ischemic stroke

Ischemic stroke (IS) is characterized by high incidence, high recurrence, and high mortality and places a heavy burden on society and families. The pathological mechanisms of IS are complex, among which secondary neurological impairment mediated by neuroinflammation is considered to be the main factor in cerebral ischemic injury. At present, there is still a lack of specific therapies to treat neuroinflammation. The tumor suppressor protein p53 has long been regarded as a key substance in the regulation of the cell cycle and apoptosis in the past. Recently, studies have found that p53 also plays an important role in neuroinflammatory diseases, such as IS. Therefore, p53 may be a crucial target for the regulation of the neuroinflammatory response. Here, we provide a comprehensive review of the potential of targeting p53 in the treatment of neuroinflammation after IS. We describe the function of p53, the major immune cells involved in neuroinflammation, and the role of p53 in inflammatory responses mediated by these cells. Finally, we summarize the therapeutic strategies of targeting p53 in regulating the neuroinflammatory response after IS to provide new directions and ideas for the treatment of ischemic brain injury.

Fatty acids secreted from head and neck cancer induce M2-like Macrophages

Tumor-infiltrating monocytes can mature into Macrophages that support tumor survival or that display antitumor properties. To explore mechanisms steering Macrophage maturation, we assessed the effects of supernatants from squamous cell carcinoma cell lines (FaDu and SCC) on monocyte-derived Macrophage maturation. Purified monocytes were incubated in medium or medium supplemented with supernatants from FaDu and SCC9 or the leukemia monocytic cell line, THP-1. Macrophages were examined for markers of maturation (CD14, CD68), activation (HLA-DR, CD86, IL15R), scavenger receptor (CD36), toll-like receptor (TLR4), M2 marker (CD206), immune checkpoint (PD-L1), and intracellular chemokine expression (IP-10). Compared to other conditions, cells incubated with FaDu or SCC9 supernatants displayed enhanced survival, down-regulation of cell surface HLA-DR, CD86, IL-15R, CD36, and intracellular IP-10 expression, and increased cell surface PD-L1, CD14, and CD206 expression. Despite expressing TLR4 and CD14, Macrophages matured in tumor supernatants failed to respond to stimulation with the canonical TLR4 agonist, LPS. These changes were accompanied by a decrease in intracellular phospho-p38 expression in tumor supernatant conditioned Macrophages. Depletion of fatty acids from tumor supernatants or treatment of cell cultures with an inhibitor of fatty acid oxidation, Etomoxir, reversed a number of these phenotypic changes induced by tumor supernatants. Additionally, Macrophages incubated with either palmitic acid or oleic acid developed similar phenotypes as cells incubated in tumor supernatants. Together, these data suggest that fatty acids derived from tumor cells can mediate the maturation of Macrophages into a cell type with limited pro-inflammatory characteristics.

Immunotherapy approaches for the treatment of diffuse midline gliomas

Diffuse midline gliomas (DMG) are a highly aggressive and universally fatal subgroup of pediatric tumors responsible for the majority of childhood brain tumor deaths. Median overall survival is less than 12 months with a 90% mortality rate at 2 years from diagnosis. Research into the underlying tumor biology and numerous clinical trials have done little to change the invariably poor prognosis. Continued development of novel, efficacious therapeutic options for DMGs remains a critically important area of active investigation. Given that DMGs are not amenable to surgical resection, have only limited response to radiation, and are refractory to traditional chemotherapy, immunotherapy has emerged as a promising alternative treatment modality. This review summarizes the various immunotherapy-based treatments for DMG as well as their specific limitations. We explore the use of cell-based therapies, oncolytic virotherapy or immunovirotherapy, immune checkpoint inhibition, and immunomodulatory vaccination strategies, and highlight the recent clinical success of anti-GD2 CAR-T therapy in diffuse intrinsic pontine glioma (DIPG) patients. Finally, we address the challenges faced in translating preclinical and early phase clinical trial data into effective standardized treatment for DMG patients.

Targeting protein phosphatases for the treatment of inflammation-related diseases: From signaling to therapy

Inflammation is the common pathological basis of autoimmune diseases, metabolic diseases, malignant tumors, and other major chronic diseases. Inflammation plays an important role in tissue homeostasis. On one hand, inflammation can sense changes in the tissue environment, induce imbalance of tissue homeostasis, and cause tissue damage. On the other hand, inflammation can also initiate tissue damage repair and maintain normal tissue function by resolving injury and restoring homeostasis. These opposing functions emphasize the significance of accurate regulation of inflammatory homeostasis to ameliorate inflammation-related diseases. Potential mechanisms involve protein phosphorylation modifications by kinases and phosphatases, which have a crucial role in inflammatory homeostasis. The mechanisms by which many kinases resolve inflammation have been well reviewed, whereas a systematic summary of the functions of protein phosphatases in regulating inflammatory homeostasis is lacking. The molecular knowledge of protein phosphatases, and especially the unique biochemical traits of each family member, will be of critical importance for developing drugs that target phosphatases. Here, we provide a comprehensive summary of the structure, the "double-edged sword" function, and the extensive signaling pathways of all protein phosphatases in inflammation-related diseases, as well as their potential inhibitors or activators that can be used in therapeutic interventions in preclinical or clinical trials. We provide an integrated perspective on the current understanding of all the protein phosphatases associated with inflammation-related diseases, with the aim of facilitating the development of drugs that target protein phosphatases for the treatment of inflammation-related diseases.

Interleukins Profiling in Umbilical Cord Mesenchymal Stem Cell-Derived Secretome

Background

Umbilical cord mesenchymal stem cells (UC-MSCs)-derived secretome is currently used in regenerative therapy. MSCs are believed to secrete a wide spectrum of bioactive molecules which give paracrine effects in immunomodulation and regenerative capacities. One group that was found in secretome is interleukins (ILs), a cytokine that plays an essential role in the process of proliferation, differentiation, maturation, migration, and adhesion of immune cells. However, as there are many types of ILs, the profile of ILs in the UC-MSCs-derived secretome has been limitedly reported. Therefore, in this study, we would like to profile and detect the interleukin concentration secreted by UC-MSCs.

Methods

UC-MSCs-derived secretome was collected from UC-MSCs passage 5 after 24- and 48-hour incubation (n=9). Secretome was filtered using 0.2 µm and stored at −80°C for further detection. All samples were normalized before the interleukin (IL-2, IL-4, IL-6, IL-9, IL-10, IL-12, IL-17A) detection using a MACSPlex Cytokine Kit.

Results

The IL-6 has the highest concentration among other interleukins in both groups and increases significantly (p<0.003) after incubation for 48 hours. The pro-inflammatory factors are decreasing while anti-inflammatory factors are increasing after 48-hour incubation.

Discussion

Our studies show that the UC-MSCs secrete pro- and anti-inflammatory interleukins. The concentration of anti-inflammatory interleukins shows to be increasing, while the pro-inflammatory interleukins are decreasing within the longer incubation time, but this not be applicable for IL-10 and IL-6. IL-6 has the highest concentration among other ILs. These results may provide important clues regarding when is the right time for secretome to be used in therapy patients, because all the molecules in the secretome can lead to many clinical manifestations.

Stool multi-omics for the study of host-microbe interactions in inflammatory bowel disease

Inflammatory Bowel Disease (IBD) is a chronic immune-mediated inflammatory disease of the gastrointestinal tract that is a growing public burden. Gut microbes and their interactions with hosts play a crucial role in disease pathogenesis and progression. These interactions are complex, spanning multiple physiological systems and data types, making comprehensive disease assessment difficult, and often overwhelming single-omic capabilities. Stool-based multi-omics is a promising approach for characterizing host-gut microbiome interactions using deep integration of technologies such as 16S rRNA sequencing, shotgun metagenomics, meta-transcriptomics, metabolomics, and metaproteomics. The wealth of information generated through multi-omic studies is poised to usher in advancements in IBD research and precision medicine. This review highlights historical and recent findings from stool-based muti-omic studies that have contributed to unraveling IBD's complexity. Finally, we discuss common pitfalls, issues, and limitations, and how future pipelines should address them to standardize multi-omics in IBD research and beyond.

Fast-tracking antibody maturation using a B cell-based display system

Affinity maturation, an essential component of antibody engineering, is crucial for developing therapeutic antibodies. Cell display system coupled with somatic hypermutation (SHM) initiated by activation-induced cytidine deaminase (AID) is a commonly used technique for affinity maturation. AID introduces targeted DNA lesions into hotspots of immunoglobulin (Ig) gene loci followed by erroneous DNA repair, leading to biased mutations in the complementary determining regions. However, systems that use an in vivo mimicking mechanism often require several rounds of selection to enrich clones possessing accumulated mutations. We previously described the human ADLib® system, which features autonomous, AID-mediated diversification in Ig gene loci of a chicken B cell line DT40 and streamlines human antibody generation and optimization in one integrated platform. In this study, we further engineered DT40 capable of receiving exogenous antibody genes and examined whether the antibody could be affinity matured. The Ig genes of three representative anti-hVEGF-A antibodies originating from the human ADLib® were introduced; the resulting human IgG1 antibodies had up to 76.4-fold improvement in binding affinities (sub-picomolar K_D) within just one round of optimization, owing to efficient accumulation of functional mutations. Moreover, we successfully improved the affinity of a mouse hybridoma-derived anti-hCDCP1 antibody using the engineered DT40, and the observed mutations remained effective in the post-humanized antibody as exhibited by an 8.2-fold increase of in vitro cytotoxicity without compromised physical stability. These results demonstrated the versatility of the novel B cell-based affinity maturation system as an easy-to-use antibody optimization tool regardless of the species of origin.Abbreviations: ADLib®: Autonomously diversifying library, ADLib® KI-AMP: ADLib® knock-in affinity maturation platform, AID: activation-induced cytidine deaminase, CDRs: complementary-determining regions, DIVAC: diversification activator, ECD: extracellular domain, FACS: fluorescence-activated cell sorting, FCM: flow cytometry, HC: heavy chainIg: immunoglobulin, LC: light chain, NGS: next-generation sequencing, PBD: pyrrolobenzodiazepine, SHM: somatic hypermutation, SPR: surface plasmon resonance.

Xuanbai Chengqi Decoction Ameliorates Pulmonary Inflammation via Reshaping Gut Microbiota and Rectifying Th17/Treg Imbalance in a Murine Model of Chronic Obstructive Pulmonary Disease

Purpose

Chronic obstructive pulmonary disease (COPD), a prevalent obstructive airway disease, has become the third most common cause of death globally. Xuanbai Chengqi decoction (XBCQ) is a traditional Chinese medicine prescription for the acute exacerbation of COPD. Here, we aimed to reveal the therapeutic effects of XBCQ administration and its molecular mechanisms mediated by Th17/Treg balance and gut microbiota.

Methods

We determined the counts of Th17 and Treg cells in the serum of 15 COPD and 10 healthy subjects. Then, cigarette smoke extract-induced COPD mice were gavaged with low, middle, and high doses of XBCQ, respectively. Weight loss, pulmonary function and inflammation, Th17/Treg ratio, and gut microbiota were measured to evaluate the efficacy of XBCQ on COPD.

Results

COPD patients had a higher Th17/Treg ratio in the serum than healthy controls, which was consistent with the results in the lung and colon of COPD mice. The middle dose of XBCQ (M-XBCQ) significantly decreased the weight loss and improved the pulmonary function (FEV0.2/FVC) in COPD mice. Moreover, M-XBCQ alleviated lung inflammation by rectifying the Th17/Treg imbalance, reducing the expressions of TNF-α, IL-1β, and MMP-9, and suppressing inflammatory cells infiltration. Meanwhile, M-XBCQ greatly improved the microbial homeostasis in COPD mice by accumulating probiotic Gordonibacter and Akkermansia but inhibiting the growth of pathogenic Streptococcus, which showed significant correlations with pulmonary injury.

Conclusion

Oral M-XBCQ could alleviate COPD exacerbations by reshaping the gut microbiota and improving the Th17/Treg balance, which aids in elucidating the mechanism through which XBCQ as a therapy for COPD.

Wip1 regulates the immunomodulatory effects of murine mesenchymal stem cells in type 1 diabetes mellitus via targeting IFN-α/BST2

Mesenchymal stem cells (MSCs) show significant therapeutic effects in type 1 diabetes mellitus (T1DM) as regulating the inflammatory processes. However, little is known about the detailed process of MSCs immunosuppression in T1DM. In this study, we investigated the effects of wild-type p53-induce phosphatase 1 (Wip1) on regulating MSCs immunosuppressive capacities in T1DM mice. We found that Wip1 knockout (Wip1-/-) MSCs had lower therapeutic effects in T1DM mice, and displayed weaker immunosuppressive capability. In vivo distribution analysis results indicated thatWip1-/-MSCs could home to the damaged pancreas and increase the expression of tumor necrosis factor-α (TNF-α), interleukin-17a (IL-17a), interferon-α(IFN-α), IFN-β, and IFN-γ, while decrease the expression of IL-4 and IL-10. Moreover, we confirmedWip1-/-MSCs exhibited weaker immunosuppressive capacity, as evidenced by enhanced expression of bone marrow stromal cell antigen 2(BST2) and IFN-α. In conclusion, these results revealed Wip1 affects MSCs immunomodulation by regulating the expression of IFN-α/BST2. Our study uncovered that Wip1 is required to regulate the therapeutic effects of MSCs on T1DM treatment, indicating a novel role of Wip1 in MSCs immunoregulation properties.

Memory-like Differentiation Enhances NK Cell Responses to Melanoma

PURPOSE

Treatment of advanced melanoma is a clinical challenge. Natural killer (NK) cells are a promising cellular therapy for T cell-refractory cancers, but are frequently deficient or dysfunctional in patients with melanoma. Thus, new strategies are needed to enhance NK-cell antitumor responses. Cytokine-induced memory-like (ML) differentiation overcomes many barriers in the NK-cell therapeutics field, resulting in potent cytotoxicity and enhanced cytokine production against blood cancer targets. However, the preclinical activity of ML NK against solid tumors remains largely undefined.

EXPERIMENTAL DESIGN

Phenotypic and functional alterations of blood and advanced melanoma infiltrating NK cells were evaluated using mass cytometry. ML NK cells from healthy donors (HD) and patients with advanced melanoma were evaluated for their ability to produce IFNγ and kill melanoma targets in vitro and in vivo using a xenograft model.

RESULTS

NK cells in advanced melanoma exhibited a decreased cytotoxic potential compared with blood NK cells. ML NK cells differentiated from HD and patients with advanced melanoma displayed enhanced IFNγ production and cytotoxicity against melanoma targets. This included ML differentiation enhancing melanoma patients' NK-cell responses against autologous targets. The ML NK-cell response against melanoma was partially dependent on the NKG2D- and NKp46-activating receptors. Furthermore, in xenograft NSG mouse models, human ML NK cells demonstrated superior control of melanoma, compared with conventional NK cells.

CONCLUSIONS

Blood NK cells from allogeneic HD or patients with advanced melanoma can be differentiated into ML NK cells for use as a novel immunotherapeutic treatment for advanced melanoma, which warrants testing in early-phase clinical trials.

Inhibition of the DNA damage response phosphatase PPM1D reprograms neutrophils to enhance anti-tumor immune responses

PPM1D/Wip1 is a negative regulator of the tumor suppressor p53 and is overexpressed in several human solid tumors. Recent reports associate gain-of-function mutations of PPM1D in immune cells with worse outcomes for several human cancers. Here we show that mice with genetic knockout of Ppm1d or with conditional knockout of Ppm1d in the hematopoietic system, in myeloid cells, or in neutrophils all display significantly reduced growth of syngeneic melanoma or lung carcinoma tumors. Ppm1d knockout neutrophils infiltrate tumors extensively. Chemical inhibition of Wip1 in human or mouse neutrophils increases anti-tumor phenotypes, p53-dependent expression of co-stimulatory ligands, and proliferation of co-cultured cytotoxic T cells. These results suggest that inhibition of Wip1 in neutrophils enhances immune anti-tumor responses.

The inhibition of WIP1 phosphatase accelerates the depletion of primordial follicles

RESEARCH QUESTION

What role does wild-type p53-induced phosphatase 1 (WIP1) play in the regulation of primordial follicle development?

DESIGN

WIP1 expression was detected in the ovaries of mice of different ages by western blotting and immunohistochemical staining. Three-day-old neonatal mouse ovaries were cultured in vitro with or without the WIP1 inhibitor GSK2830371 (10 μM) for 4 days. Ovarian morphology, follicle growth and follicle classification were analysed and the PI3K-AKT-mTOR signal pathway and the WIP1-p53-related mitochondrial apoptosis pathway evaluated.

RESULTS

WIP1 expression was downregulated with age. Primordial follicles were significantly decreased in the GSK2830371-treated group, without a significant increase in growing follicles. The ratio of growing follicles to primordial follicles was not significantly different between the control and GSK2830371 groups, and no significant variation was observed in the PI3K-AKT-mTOR signal pathway. The inhibition of WIP1 phosphatase accelerated primordial follicle atresia by activating the p53-BAX-caspase-3 pathway.

CONCLUSIONS

These findings reveal that WIP1 participates in regulating primordial follicle development and that inhibiting WIP1 phosphatase leads to massive primordial follicle loss via interaction with the p53-BAX-caspase-3 pathway. This might also provide valuable information for understanding decreased ovarian reserve during ovarian ageing.

The p53 status in rheumatoid arthritis with focus on fibroblast-like synoviocytes

P53 is a transcription factor that regulates many signaling pathways like apoptosis, cell cycle, DNA repair, and cellular stress responses. P53 is involved in inflammatory responses through the regulation of inflammatory signaling pathways, induction of cytokines, and matrix metalloproteinase expression. Also, p53 regulates immune responses through modulating Toll-like receptors expression and innate and adaptive immune cell differentiation and maturation. P53 is a modulator of the apoptosis and proliferation processes through regulating multiple anti and pro-apoptotic genes. Rheumatoid arthritis (RA) is categorized as an invasive inflammatory autoimmune disease with irreversible deformity of joints and bone resorption. Different immune and non-immune cells contribute to RA pathogenesis. Fibroblast-like synoviocytes (FLSs) have been recently introduced as a key player in the pathogenesis of RA. These cells in RA synovium produce inflammatory cytokines and matrix metalloproteinases which results in synovitis and joint destruction. Besides, hyper proliferation and apoptosis resistance of FLSs lead to synovial hyperplasia and bone and cartilage destruction. Given the critical role of p53 in inflammation, apoptosis, and cell proliferation, lack of p53 function (due to mutation or low expression) exerts a prominent role for this gene in the pathogenesis of RA. This review focuses on the role of p53 in different mechanisms and cells (specially FLSs) that involved in RA pathogenesis.

Targeting Neutrophils in Sepsis: From Mechanism to Translation

Sepsis is a life-threatening condition caused by a dysregulated host response to infection. Although our understanding in the pathophysiological features of sepsis has increased significantly during the past decades, there is still lack of specific treatment for sepsis. Neutrophils are important regulators against invading pathogens, and their role during sepsis has been studied extensively. It has been suggested that the migration, the antimicrobial activity, and the function of neutrophil extracellular traps (NETs) have all been impaired during sepsis, which results in an inappropriate response to primary infection and potentially increase the susceptibility to secondary infection. On the other hand, accumulating evidence has shown that the reversal or restoration of neutrophil function can promote bacterial clearance and improve sepsis outcome, supporting the idea that targeting neutrophils may be a promising strategy for sepsis treatment. In this review, we will give an overview of the role of neutrophils during sepsis and discuss the potential therapeutic strategy targeting neutrophils.

Loss of Wip1 aggravates brain injury after ischaemia/reperfusion by overactivating microglia

Background and purpose

The inflammatory response mediated by microglia/macrophages is closely related to cerebral ischaemia/reperfusion injury. Wild-type p53-induced protein phosphatase 1 (Wip1), a serine/threonine phosphatase, is expressed in various tissues. A growing number of reports have suggested that Wip1 is a negative regulator of inflammation in peripheral tissue; however, its role in the central nervous system (CNS) remains unclear. This study aimed to clarify whether Wip1 can inhibit CNS inflammation by regulating microglia/macrophage functions after ischaemic injury.

Methods

A model of middle cerebral artery occlusion and reperfusion was established in mice. CNS inflammation was simulated by lipopolysaccharide treatment of primary microglia. Laser speckle imaging was used to monitor regional cerebral blood flow. Behavioural outcomes were assessed with a TreadScan gait analysis system. TTC staining was used to evaluate the infarct volume, and western blotting and immunofluorescence staining were applied to detect the phenotypical transformation of microglia. ELISA was performed to detect the levels of inflammatory factors.

Results

Wip1 expression was increased after ischaemia/reperfusion. Wip1-knockout (KO) mice displayed more severe brain injury than wild-type mice, as indicated by aggravated motor dysfunction, greater brain infarct volumes and higher expression of inflammatory cytokines (interleukin-6 and tumour necrosis factor alpha) in the brain. We also found that Wip1 depletion increased microglial/macrophage activation in both in vitro and in vivo models, which all showed activation of microglia/macrophages. Lentivirus-Ppm1d reversed the injury induced by Wip1-KO.

Conclusions

Our results suggest that Wip1 may inhibit neuroinflammation by inhibiting microglial/macrophage activation after brain ischaemia/reperfusion injury.

The intrinsic and extrinsic elements regulating inflammation

Inflammation is a sophisticated biological tissue response to both extrinsic and intrinsic stimuli. Although the pathological aspects of inflammation are well appreciated, there are still rooms for understanding the physiological functions of the inflammation. Recent studies have focused on mechanisms, context and the role of physiological inflammation. Besides, there have been progress in the comprehension of commensal microbiota, immunometabolism, cancer and intracellular signaling events' roles that impact on the regulation of inflammation. Despite the fact that inflammatory responses are vital through tissue damage, understanding the mechanisms to turn off the finished or unnecessary inflammation is crucial for restoring homeostasis. Inflammation seems to be a smart process that acts like two edges of a sword, meaning that it has both protective and deleterious consequences. Knowing both edges and the regulation processes will help the future understanding and therapy for various diseases.

The biological function and the regulatory roles of wild-type p53-induced phosphatase 1 in immune system

Wild-type p53-induced phosphatase 1 (WIP1) belongs to the protein phosphatase 2C (PP2C) family and is a mammalian serine/threonine specific protein phosphatase to dephosphorylate numerous signaling molecules. Mammalian WIP1 regulates a wide array of targeting molecules and plays key regulatory roles in many cell processes such as DNA damage and repair, cell proliferation, differentiation, apoptosis, and senescence. WIP1 promotes the formation and development of tumors as an oncogene and a negative regulator of p53. It is also involved in the regulation of aging, neurological diseases and immune diseases. Recent studies demonstrated the critical roles of WIP1 in the differentiation and function of immune cells including T cells, neutrophils and macrophages. In the present manuscript, we briefly summarized the expression patterns, biological function and the target molecules and signal pathways of WIP1 and mainly discussed the latest advances on the regulatory effects of WIP1 in the immune system. WIP1 may be a potential target molecule to treat cancers and immune diseases such as allergic asthma.

A New Intra-Specific and High-Resolution Genetic Map of Eggplant Based on a RIL Population, and Location of QTLs Related to Plant Anthocyanin Pigmentation and Seed Vigour

Eggplant is the second most important solanaceous berry-producing crop after tomato. Despite mapping studies based on bi-parental progenies and GWAS approaches having been performed, an eggplant intraspecific high-resolution map is still lacking. We developed a RIL population from the intraspecific cross ‘305E40’, (androgenetic introgressed line carrying the locus Rfo-Sa1 conferring Fusarium resistance) x ‘67/3’ (breeding line whose genome sequence was recently released). One hundred and sixty-three RILs were genotyped by a genotype-by-sequencing (GBS) approach, which allowed us to identify 10,361 polymorphic sites. Overall, 267 Gb of sequencing data were generated and ~773 M Illumina paired end (PE) reads were mapped against the reference sequence. A new linkage map was developed, including 7249 SNPs assigned to the 12 chromosomes and spanning 2169.23 cM, with iaci@liberoan average distance of 0.4 cM between adjacent markers. This was used to elucidate the genetic bases of seven traits related to anthocyanin content in different organs recorded in three locations as well as seed vigor. Overall, from 7 to 17 QTLs (at least one major QTL) were identified for each trait. These results demonstrate that our newly developed map supplies valuable information for QTL fine mapping, candidate gene identification, and the development of molecular markers for marker assisted selection (MAS) of favorable alleles.

Turn and Face the Strange: A New View on Phosphatases

Phosphorylation as a post-translational modification is critical for cellular homeostasis. Kinases and phosphatases regulate phosphorylation levels by adding or removing, respectively, a phosphate group from proteins or other biomolecules. Imbalances in phosphorylation levels are involved in a multitude of diseases. Phosphatases are often thought of as the black sheep, the strangers, of phosphorylation-mediated signal transduction, particularly when it comes to drug discovery and development. This is due to past difficulties to study them and unsuccessful attempts to target them; however, phosphatases have regained strong attention and are actively pursued now in clinical trials. By giving examples for current hot topics in phosphatase biology and for new approaches to target them, it is illustrated here how and why phosphatases made their comeback, and what is envisioned to come in the future.

Emerging Roles of Sonic Hedgehog in Adult Neurological Diseases: Neurogenesis and Beyond

Sonic hedgehog (Shh), a member of the hedgehog (Hh) family, was originally recognized as a morphogen possessing critical characters for neural development during embryogenesis. Recently, however, Shh has emerged as an important modulator in adult neural tissues through different mechanisms such as neurogenesis, anti-oxidation, anti-inflammation, and autophagy. Therefore, Shh may potentially have clinical application in neurodegenerative diseases and brain injuries. In this article, we present some examples, including ours, to show different aspects of Shh signaling and how Shh agonists or mimetics are used to alter the neuronal fates in various disease models, both in vitro and in vivo. Other potential mechanisms that are discussed include alteration of mitochondrial function and anti-aging effect; both are critical for age-related neurodegenerative diseases. A thorough understanding of the protective mechanisms elicited by Shh may provide a rationale to design innovative therapeutic regimens for various neurodegenerative diseases.

Wip1 regulates blood-brain barrier function and neuro-inflammation induced by lipopolysaccharide via the sonic hedgehog signaling signaling pathway

The blood brain barrier (BBB) is a diffusion barrier that maintains the brain environment. Wip1 is a nuclear phosphatase induced by many factors and involved in various stresses, tumorigenesis, organismal aging, and neurogenesis. Wip1's role in BBB integrity has not been thoroughly investigated. The purpose of the present study was to investigate the effect and mechanism of Wip1 on lipopolysaccharide (LPS)-induced BBB dysfunction and inflammation in an in vitro BBB model. The in vitro BBB model was established by co-culturing human brain-microvascular endothelial cells and human astrocytes and then exposing them to 1μg/ml LPS for 6, 12, 18, 24, and 48h. Wip1 expression was significantly elevated by LPS treatment. Knockdown of Wip1 aggravated the increased permeability and decreased transepithelial electrical resistance, protein expression of ZO-1, and occludin induced by LPS. Wip1 silencing augmented the elevated inflammatory cytokines TNF-α, IL-1β, IL-12, and IL-6 of the BBB induced by LPS, whereas overexpression of Wip1 showed a contrary effect. Sonic hedgehog signaling (SHH) was activated by Wip1 overexpression and inhibited by Wip1 silencing. Additionally, activating or inhibiting the SHH pathway by purmorphamine or cyclopamine, respectively, abolished the Wip1-induced changes in transepithelial electrical resistance and permeability and inflammatory responses in the LPS-injured BBB model. Our results demonstrate that Wip1 may protect the BBB against LPS-induced integrity disruption and inflammatory response through the SHH signaling pathway.

Limiting inflammation-the negative regulation of NF-κB and the NLRP3 inflammasome

A properly mounted immune response is indispensable for recognizing and eliminating danger arising from foreign invaders and tissue trauma. However, the 'inflammatory fire' kindled by the host response must be tightly controlled to prevent it from spreading and causing irreparable damage. Accordingly, acute inflammation is self-limiting and is normally attenuated after elimination of noxious stimuli, restoration of homeostasis and initiation of tissue repair. However, unresolved inflammation may lead to the development of chronic autoimmune and degenerative diseases and cancer. Here, we discuss the key molecular mechanisms that contribute to the self-limiting nature of inflammatory signaling, with emphasis on the negative regulation of the NF-κB pathway and the NLRP3 inflammasome. Understanding these negative regulatory mechanisms should facilitate the development of much-needed therapeutic strategies for treatment of inflammatory and autoimmune pathologies.

Wip1 Deficiency Promotes Neutrophil Recruitment to the Infection Site and Improves Sepsis Outcome

Sepsis is defined as an uncontrolled host response to infection, and no specific therapy or drugs have been used in clinical trials currently. Discovering new therapeutic targets for sepsis treatment has always been a central problem in the field of sepsis research. Neutrophils stand at the first line in controlling infection and have been identified to be dysregulated with impaired migration and antimicrobial function during sepsis. Based on our previous results on demonstrating wild-type p53-induced phosphatase 1 in controlling neutrophil development, we explored the possible relationship among Wip1, neutrophils, and sepsis in the present study. Wip1-deficient mice exhibited improved outcomes in cecal ligation and puncture (CLP)-induced sepsis model with enhanced bacterial clearance and less multi-organ damage. The protection seen in Wip1 KO mice was mainly due to an increased accumulation of neutrophils in the primary infectious locus mediated by the decreased internalization of CXCR2, as well as by an increased antimicrobial function. Additionally, we also identified a negative correlation between CXCR2 and Wip1 in human neutrophils during sepsis. Pharmacological inhibition of Wip1 with its inhibitor can also prevent the internalization of CXCR2 on human neutrophils treated with lipopolysaccharides in vitro and significantly improve the outcome in CLP-induced sepsis model. Taken together, our results demonstrate that Wip1 can negatively regulate neutrophil migration and antimicrobial immunity during sepsis and inhibition of Wip1 can be a potential therapeutic target for sepsis treatment.

WIP1 phosphatase as pharmacological target in cancer therapy

DNA damage response (DDR) pathway protects cells from genome instability and prevents cancer development. Tumor suppressor p53 is a key molecule that interconnects DDR, cell cycle checkpoints, and cell fate decisions in the presence of genotoxic stress. Inactivating mutations in TP53 and other genes implicated in DDR potentiate cancer development and also influence the sensitivity of cancer cells to treatment. Protein phosphatase 2C delta (referred to as WIP1) is a negative regulator of DDR and has been proposed as potential pharmaceutical target. Until recently, exploitation of WIP1 inhibition for suppression of cancer cell growth was compromised by the lack of selective small-molecule inhibitors effective at cellular and organismal levels. Here, we review recent advances in development of WIP1 inhibitors and discuss their potential use in cancer treatment.