Recent Advancements in Nanomedicine for‘Cold’Tumor Immunotherapy

Although current anticancer immunotherapies using immune checkpoint inhibitors(ICIs)have been reported with a high clinical success rate,numerous patients still bear‘cold’tumors with insufficient T cell infiltration and low immunogenicity,responding poorly to ICI therapy.Considering the advancements in precision medicine,in-depth mechanism studies on the tumor immune microenvironment(TIME)among cold tumors are required to improve the treatment for these patients.Nanomedicine has emerged as a promising drug delivery system in anticancer immunotherapy,activates immune function,modulates the TIME,and has been applied in combination with other anticancer therapeutic strategies.This review initially summarizes the mechanisms underlying immunosuppressive TIME in cold tumors and addresses the recent advancements in nanotechnology for cold TIME reversal-based therapies,as well as a brief talk about the feasibility of clinical translation.

Inflection Point Age in the Middle and Older Women—Jiangxi Province,China,2020-2022

Summary What is already known about this topic?Previous studies have predominantly examined the micro-level aspects of women aging inflection points,while macro-level research using big data on the inflection points of aging among middle-aged and elderly women in China is currently limited.

BMAL1 regulates mitochondrial fission and mitophagy through mitochondrial protein BNIP3 and is critical in the development of dilated cardiomyopathy

Dysregulation of circadian rhythms associates with cardiovascular disorders.It is known that deletion of the core circadian gene Bma/1 in mice causes dilated car-diomyopathy.However,the biological rhythm regulation system in mouse is very different from that of humans.Whether BMAL1 plays a role in regulating human heart function remains unclear.Here we generated a BMAL1 knockout human embryonic stem cell(hESC)model and further derived human BMAL1 deficient cardiomy-ocytes.We show that BMAL1 deficient hESC-derived cardiomyocytes exhibited typical phenotypes of dilated cardiomyopathy including attenuated contractility,cal-cium dysregulation,and disorganized myofilaments.In addition,mitochondrial fission and mitophagy were suppressed in BMAL1 deficient hESC-cardiomyocytes,which resulted in significantly attenuated mitochondrial oxidative phosphorylation and compromised cardiomy-ocyte function.We also found that BMAL1 binds to the E-box element in the promoter region of BNIP3 gene and specifically controls BNIP3 protein expression.BMAL1 knockout directly reduced BNIP3 protein level,causing compromised mitophagy and mitochondria dysfunction and thereby leading to compromised cardiomyocyte function.Our data indicated that the core circadian gene S/VMLf is critical for normal mitochondria activities and cardiac function.Circadian rhythm disruption may directly link to compromised heart function and dilated cardiomyopathy in humans.

Endoscopic findings of gastrointestinal involvement in Chinese patients with Behcet's disease

AIM:To report the incidence,clinical features and outcomes of gastrointestinal(GI)involvement in Behcet’s disease(BD).METHODS:A total of 168 consecutive patients with BD were screened and upper and lower GI endoscopies were performed in 148 patients.Four hundred age-and sex-matched controls were enrolled for comparison.RESULTS:Fifty-two(35.1%)patients had GI lesions.After a mean follow-up of 10 mo,ileocecal ulcers had been confirmed in 20 patients,including active ulcer(s)in 18 patients,but no ileocecal ulceration was found in controls.GI symptoms were present in 14 patients with active ulcer(s),while 4 patients with smaller ulcer were asymptomatic.Endoscopic features of ileocecalulcer were:a single ulcer(50%),larger than 1 cm in diameter(72.2%),and round/oval or volcano-type in shape(83.3%).Compared with patients without GI involvement,less ocular lesions,lower levels of albumin,erythrocyte count and hemoglobin,and higher levels of C-reactive protein and erythrocyte sedimentation rate were confirmed in the intestinal BD group.Four patients had esophageal ulcers in the BD group but no case in controls.The other endoscopic findings were similar between the two groups.The prevalence of Helicobacter pylori infection was similar in both groups.Most patients received an immunomodulator and responded well.CONCLUSION:GI lesions commonly occur in Chinese BD patients.The most frequently involved area is the ileocecal region.Esophageal ulcer might be a rare but unique lesion.

A neutrophil-biomimic platform for eradicating metastatic breast cancer stem-like cells by redox microenvironment modulation and hypoxia-triggered differentiation therapy

Metastasis accounts for 90%of breast cancer deaths,where the lethality could be attributed to the poor drug accumulation at the metastatic loci.The tolerance to chemotherapy induced by breast cancer stem cells(BCSCs)and their particular redox microenvironment further aggravate the therapeutic dilemma.To be specific,therapy-resistant BCSCs can differentiate into heterogeneous tumor cells constantly,and simultaneously dynamic maintenance of redox homeostasis promote tumor cells to retro-differentiate into stem-like state in response to cytotoxic chemotherapy.Herein,we develop a specifically-designed biomimic platform employing neutrophil membrane as shell to inherit a neutrophil-like tumor-targeting capability,and anchored chemotherapeutic and BCSCs-differentiating reagents with nitroimidazole(NI)to yield two hypoxia-responsive prodrugs,which could be encapsulated into a polymeric nitroimidazole core.The platform can actively target the lung metastasis sites of triple negative breast cancer(TNBC),and release the escorted drugs upon being triggered by the hypoxia microenvironment.During the responsiveness,the differentiating agent could promote transferring BCSCs into non-BCSCs,and simultaneously the nitroimidazole moieties conjugated on the polymer and prodrugs could modulate the tumor microenvironment by depleting nicotinamide adenine dinucleotide phosphate hydrogen(NADPH)and amplifying intracellular oxidative stress to prevent tumor cells retro-differentiation into BCSCs.In combination,the BCSCs differentiation and tumor microenvironment modulation synergistically could enhance the chemotherapeutic cytotoxicity,and remarkably suppress tumor growth and lung metastasis.Hopefully,this work can provide a new insight in to comprehensively treat TNBC and lung metastasis using a versatile platform.

Expression of Phospho-MeCP2s in the Developing Rat Brain and Function of Postnatal MeCP2 in Cerebellar Neural Cell Development

Abnormal expression and dysfunction of methyl-CpG binding protein 2 （MeCP2） cause Rett syndrome （RTT）. The diverse phosphorylation modifications modulate MeCP2 function in neural cells. Using western blot and immunohistochemistry, we examined the expression patterns of MeCP2 and three phospho-MeCP2s （pMeCP2s） in the developing rat brain. The expression of MeCP2 and phospho-S80 （pS80） MeCP2 increased while pS421 MeCP2 and pS292 MeCP2 decreased with brain maturation. In contrast to the nuclear localization of MeCP2 and pS80 MeCP2, pS421 MeCP2 and pS292 MeCP2 were mainly expressed in the cytoplasmic com- partment. Apart from their distribution in neurons, they were also detected at a low level in astrocytes. Postnatallyinitiated MeCP2 deficiency affected cerebellar neural cell development, as determined by the abnormal expression of GFAP, DCX, Tuj 1, MAP-2, and calbindin-D28k. Together, these results demonstrate that MeCP2 and diverse pMeCP2s have distinct features of spatio-temporal expression in the rat brain, and that the precise levels of MeCP2 in the postnatal period are vital to cerebellar neural cell development.

Emerging landscapes of nanosystems based on pre-metastatic microenvironment for cancer theranostics

The emergence of disseminated metastasis is the leading cause of mortality in patients with malignant tumor.The pre-metastatic microenvironment,including the primary tumor-derived components,pre-metastatic niche(PMN),circulating tumor cells(CTCs),micro-metastases,and tumor immune microenvironment(TIM),are the crucial factors to initiate metastasis and form macro-metastases.It may be a more promising strategy for directly targeting pre-metastatic microenvironment-interrelated factors and cells before they have the chance to form secondary tumors to prevent metastasis.During recent years,a variety of nanosystems,with specific microstructures and functional properties,have been devised to selectively target pre-metastatic cells components and interrelated molecular,and exhibited strong potential on anti-metastatic therapy by absorbing and neutralizing primary tumor-derived components,preventing establishment of the PMN,eliminating the CTCs,eradicating the micro-metastases and modulating the TIM.In this review,we comprehensively review the emerging nanosystems based on the pre-metastatic microenvironments.Hopefully,this review can cast new lights for early preventing and attenuating metastatic progression.

The roles of Mesp family proteins： functional diversity and redundancy in differentiation of pluripotent stem cells and mammalian mesodermal development

Mesp family proteins comprise two members named mesodermal posterior 1 （Mespl） and mesodermal pos- terior 2 （Mesp2）. Both Mespl and Mesp2 are transcrilption factors and they share an almost identical basic helix-loop-helix motif. They have been shown to play critical regulating roles in mammalian heart and somite development. Mespl sits in the core of the complicated regulatory network for generation of cardiovascular progenitors while Mesp2 is central for somitogenesis. Here we summarize the similarities and differences in their molecular functions during mammalian early mesodermal development and discuss possible future research directions for further study of the functions of Mespl and Mesp2. A comprehensive knowledge of molecular functions of Mesp family proteins will even- tually help us better understand mammalian heart development and somitogenesis as well as improve the production of specific ceil types from pluripotent stem cells for future regenerative therapies.

Overexpressed NEDD8 as a potential therapeutic target in esophageal squamous cell carcinoma

Objective:The hyperactivated neddylation pathway plays an important role in tumorigenesis and is emerging as a promising anticancer target.We aimed to study whether NEDD8(neural precursor cell expressed,developmentally down-regulated 8)might serve as a therapeutic target in esophageal squamous cell carcinoma(ESCC).Methods:The clinical relevance of NEDD8 expression was evaluated by using The Cancer Genome Atlas(TCGA)database and tissue arrays.NEDD8-knockdown ESCC cells generated with the CRISPR/Cas9 system were used to explore the anticancer effects and mechanisms.Quantitative proteomic analysis was used to examine the variations in NEDD8 knockdown-induced biological pathways.The cell cycle and apoptosis were assessed with fluorescence activated cell sorting.A subcutaneous-transplantation mouse tumor model was established to investigate the anticancer potential of NEDD8 silencing in vivo.Results:NEDD8 was upregulated at both the mRNA and protein expression levels in ESCC,and NEDD8 overexpression was associated with poorer overall patient survival(mRNA level:P=0.028,protein level:P=0.026,log-rank test).Downregulation of NEDD8 significantly suppressed tumor growth both in vitro and in vivo.Quantitative proteomic analysis revealed that downregulation of NEDD8 induced cell cycle arrest,DNA damage,and apoptosis in ESCC cells.Mechanistic studies demonstrated that NEDD8 knockdown led to the accumulation of cullin-RING E3 ubiquitin ligases(CRLs)substrates through inactivation of CRLs,thus suppressing the malignant phenotype by inducing cell cycle arrest and apoptosis in ESCC.Rescue experiments demonstrated that the induction of apoptosis after NEDD8 silencing was attenuated by DR5 knockdown.Conclusions:Our study elucidated the anti-ESCC effects and underlying mechanisms of NEDD8 knockdown,and validated NEDD8 as a potential target for ESCC therapy.

Recent advances in nanomedicines for the treatment of ischemic stroke

Ischemic stroke is a cerebrovascular disease normally caused by interrupted blood supply to the brain.Ischemia would initiate the cascade reaction consisted of multiple biochemical events in the damaged areas of the brain,where the ischemic cascade eventually leads to cell death and brain infarction.Extensive researches focusing on different stages of the cascade reaction have been conducted with the aim of curing ischemic stroke.However,traditional treatment methods based on antithrombotic therapy and neuroprotective therapy are greatly limited for their poor safety and treatment efficacy.Nanomedicine provides new possibilities for treating stroke as they could improve the pharmacokinetic behavior of drugs in vivo,achieve effective drug accumulation at the target site,enhance the therapeutic effect and meanwhile reduce the side effect.In this review,we comprehensively describe the pathophysiology of stroke,traditional treatment strategies and emerging nanomedicines,summarize the barriers and methods for transporting nanomedicine to the lesions,and illustrate the latest progress of nanomedicine in treating ischemic stroke,with a view to providing a new feasible path for the treatment of cerebral ischemia.

MicroRNA-365 Knockdown Prevents Ischemic Neuronal Injury by Activating Oxidation Resistance 1-Mediated Antioxidant Signals

Micro RNA-365(mi R-365) is upregulated in the ischemic brain and is involved in oxidative damage in the diabetic rat. However, it is unclear whether mi R-365 regulates oxidative stress(OS)-mediated neuronal damage after ischemia. Here, we used a transient middle cerebral artery occlusion model in rats and the hydrogen peroxide-induced OS model in primary cultured neurons to assess the roles of mi R-365 in neuronal damage. We found that mi R-365 exacerbated ischemic brain injury and OS-induced neuronal damage and was associated with a reduced expression of OXR1(Oxidation Resistance 1). In contrast, mi R-365 antagomir alleviated both the brain injury and OXR1 reduction. Luciferase assays indicated that mi R-365 inhibited OXR1 expression by directly targeting the 30-untranslated region of Oxr1. Furthermore, knockdown of OXR1 abolished the neuroprotective and antioxidant effects of the mi R-365 antagomir. Our results suggest that mi R-365 upregulationincreases oxidative injury by inhibiting OXR1 expression,while its downregulation protects neurons from oxidative death by enhancing OXR1-mediated antioxidant signals.

Role of circadian gene Clock during differentiation of mouse pluripotent stem cells

Biological rhythms controlled by the circadian clock are absent in embryonic stem cells （ESCs）. However, they start to develop during the differentiation of pluripotent ESCs to downstream cells. Conversely, biological rhythms in adult somatic cells disappear when they are reprogrammed into induced pluripotent stem cells （iPSCs）. These studies indicated that the development of biological rhythms in ESCs might be closely associated with the maintenance and differentiation of ESCs. The core circadian gene Clock is essential for regulation of biological rhythms. Its role in the development of biological rhythms of ESCs is totally unknown. Here, we used CRISPR/CAS9-mediated genetic editing techniques, to completely knock out the Clock expression in mouse ESCs. By AP, teratoma formation, quantitative real-time PCR and Immunofluorescent staining, we did not find any dif- ference between Clock knockout mESCs and wild type mESCs in morphology and pluripotent capability under the pluripotent state. In brief, these data indicated Clock did not influence the maintaining of pluripotent state. However, they exhibited decreased proliferation and increased apoptosis. Furthermore, the biological rhythms failed to develop in Clock knockout mESCs after spontaneous differentiation, which indicated that there was no compensational factor in most peripheral tissues as described in mice models before （DeBruyne et ah, 2007b）. After spontaneous differentiation, loss of CLOCK protein due to Clock gene silencing induced spontaneous differentiation of mESCs, indicating an exit from the pluripotent state, or its differentiating ability. Our findings indicate that the core circadian gene Clock may be essential during normal mESCs differentiation by regulating mESCs proliferation, apoptosis and activity.

NEDD8-conjugating enzyme UBC12 as a novel therapeutic target in esophageal squamous cell carcinoma

Dear Editor,Esophageal squamous cell carcinoma(ESCC)is the major histologic subtype of esophageal cancer with high incidence and mortality.1 However,few achievements have been made in the development of targeted drugs.2 Neddylation,a reversible post-translational modification,attaches ubiquitin-like molecule NEDD8 to substrates in a three-step enzymatic reaction catalyzed by NEDD8-activating enzyme E1(NAE,NAE1 and UBA3 heterodimer),NEDD8-conjugating enzyme E2s(UBE2M/UBC12 or UBE2F)and substrate-specific NEDD8-E3 ligases.3 The best-characterized substrates of neddylation are cullin family proteins,the essential components of multiunit Cullin-RING ubiquitin ligases(CRLs).4 Currently,the inhibition of cullin neddylation by targeting overactivated neddylation pathway has emerged as an attractive approach for anticancer therapy.5,6 Our previous study reported that MLN4924,a specific inhibitor of NAE,significantly inhibited the tumor growth of ESCC by blocking cullin neddylation and inactivating CRLs activity.7 However,recent studies found that MLN4924 treatment-emergent NAE mutations would confer the drug resistance.8,9 Therefore,it is urgent to identify other neddylation enzymes(E2s or E3s)as alternative anticancer targets and develop novel anti-ESCC strategies.

Isogenic human pluripotent stem cell disease models reveal ABRA deficiency underlies cTnT mutation-induced familial dilated cardiomyopathy

Dear Editor,Dilated cardiomyopathy(DCM)is a common form of inherited cardiomyopathy.In the past decades,single mutations in various genes encoding sarcomeric,cytoskeletal,and channel proteins etc.have been found to be associated with DCM(Hershberger et al.,2013;McNally and Mestroni,2017).However,the mechanisms how single mutations in sarcomeric or structural genes lead to the disease remain elusive.An interesting phenomenon often seen in familial cardiomyopathy is that different single mutations on the same gene can cause either DCM or hypertrophic cardiomyopathy(HCM)(Kathiresan and Srivastava,2012),which exhibit almost opposite disease phenotypes.DCM is characterized by thinned myocardium and septum,ventricular chamber dilation,and systolic dysfunction(Jefferies and Towbin,2010;McNally and Mestroni,2017),while HCM exhibits thickened myocardium and septum,reduced ventricular chamber,and diastolic dysfunction(Richard et al.,2003).At the cellular level,HCM cardiomyocytes exhibit concentric hypertrophy characterized by assembly of myofilaments in parallel and widening of the myocytes.In contrast,DCM cardiomyocytes show eccentric hypertrophy,with assembly of the myofilaments in series and myocyte elongation(Kehat and Molkentin,2010).