Chloroquine modulates antitumor immune response by resetting tumor-associated macrophages toward M1 phenotype

Chloroquine-Induced DNA Damage Synergizes with Nonhomologous End Joining Inhibition to Cause Ovarian Cancer Cell Cytotoxicity

Ovarian cancer (OC) is the most lethal gynecological malignancy; therefore, more effective treatments are urgently needed. We recently reported that chloroquine (CQ) increased reactive oxygen species (ROS) in OC cell lines (OCCLs), causing DNA double-strand breaks (DSBs). Here, we analyzed whether these lesions are repaired by nonhomologous end joining (NHEJ), one of the main pathways involved in DSB repair, and if the combination of CQ with NHEJ inhibitors (NHEJi) could be effective against OC. We found that NHEJ inhibition increased the persistence of γH2AX foci after CQ-induced DNA damage, revealing an essential role of this pathway in the repair of the lesions. NHEJi decreased the proliferation of OCCLs and a strong in vitro synergistic effect on apoptosis induction was observed when combined with CQ. This effect was largely abolished by the antioxidant N-Acetyl-L-cysteine, revealing the critical role of ROS and DSB generation in CQ/NHEJi-induced lethality. We also found that the NHEJ efficiency in OCCLs was not affected by treatment with Panobinostat, a pan-histone deacetylase inhibitor that also synergizes with CQ in OCCLs by impairing homologous recombination. Accordingly, the triple combination of CQ-NHEJi-Panobinostat exerted a stronger in vitro synergistic effect. Altogether, our data suggest that the combination of these drugs could represent new therapeutic strategies against OC.

TFEB induces mitochondrial itaconate synthesis to suppress bacterial growth in macrophages

Successful elimination of bacteria in phagocytes occurs in the phago-lysosomal system, but also depends on mitochondrial pathways. Yet, how these two organelle systems communicate is largely unknown. Here we identify the lysosomal biogenesis factor transcription factor EB (TFEB) as regulator for phago-lysosome-mitochondria crosstalk in macrophages. By combining cellular imaging and metabolic profiling, we find that TFEB activation, in response to bacterial stimuli, promotes the transcription of aconitate decarboxylase (Acod1, Irg1) and synthesis of its product itaconate, a mitochondrial metabolite with antimicrobial activity. Activation of the TFEB-Irg1-itaconate signalling axis reduces the survival of the intravacuolar pathogen Salmonella enterica serovar Typhimurium. TFEB-driven itaconate is subsequently transferred via the Irg1-Rab32-BLOC3 system into the Salmonella-containing vacuole, thereby exposing the pathogen to elevated itaconate levels. By activating itaconate production, TFEB selectively restricts proliferating Salmonella, a bacterial subpopulation that normally escapes macrophage control, which contrasts TFEB's role in autophagy-mediated pathogen degradation. Together, our data define a TFEB-driven metabolic pathway between phago-lysosomes and mitochondria that restrains Salmonella Typhimurium burden in macrophages in vitro and in vivo.

The role of glycolysis and lactate in the induction of tumor-associated macrophages immunosuppressive phenotype

Growing evidence highlights that glycolysis and tumor-derived lactate could skew tumor-associated macrophages (TAMs) toward an immunosuppressive phenotype. However, the updated research has not been systematically summarized yet. TAMs are educated by the tumor microenvironment (TME) and exert immunosuppressive functions and tumorigenic effects via multiple biological processes. It is well known that lactate generated by aerobic glycolysis is significantly accumulated in TME and promotes tumor progression in solid tumors. Moreover, some recent research demonstrated that glycolysis is activated in TAMs to support M2-like polarization, which is absolutely in contrast with the metabolic profile of M2 macrophages in inflammation. Notably, lactate produced by high levels of glycolysis is not only a metabolic by-product but also an oncometabolite. TAMs could access the biological information delivered by lactate and further enhance protumor functions such as immunosuppression and angiogenesis. Here, we outline the connection between glycolysis and TAM phenotype to elucidate the metabolic characteristics of TAMs. Further, insights into the specific molecular mechanisms of lactate-induced TAM polarization and potential therapeutic targets are summarized. We sought to discuss the reciprocal interaction between tumor cells and TAMs mediated by lactate, which will lay a foundation for the research aiming to elucidate the complex functions of TAMs.

HDAC6 is a prognostic biomarker that mediates IL-13 expression to regulate macrophage polarization through AP-1 in oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is a common malignant tumor worldwide that is characterized by abnormal lesions or malignant hyperplasia of soft and hard tissues in the oral cavity. Previous research has found that HDAC6 may be a potential therapeutic target for cancer patients and has the ability to regulate immune cells. However, the mechanism of HDAC6 in OSCC pathogenesis is unclear. We collected clinical samples and analyzed the level of HDAC6 in OSCC patients. The results showed that in the high HDAC6 expression group, HDAC6 expression was positively correlated with the grade of OSCC (R = 0.182, P = 0.036) and that this group had a 3.248-fold increase in the mortality risk compared with the low HDAC6 expression group (P = 0.003). Survival analysis also identified a correlation between the expression of HDAC6 and overall survival in OSCC patients, and it was found that the expression of HDAC6 was inversely correlated with survival (P ≤ 0.001). In addition, we found that HDAC6 induced IL-13 expression through AP-1, resulting in M2 polarization of macrophages. Together, these results demonstrate that the level of HDAC6 may be a useful prognostic biomarker and offer a novel immune cell-related therapeutic strategy of targeting IL-13 in OSCC.

The feasibility of proteomics sequencing based immune-related prognostic signature for predicting clinical outcomes of bladder cancer patients

Background

Bladder cancer (BCa) shows its potential immunogenity in current immune-checkpoint inhibitor related immunotherapies. However, its therapeutic effects are improvable and could be affected by tumor immune microenvironment. Hence it is interesting to find some more prognostic indicators for BCa patients concerning immunotherapies.

Methods

In the present study, we retrospect 129 muscle-invasive BCa (MIBC) patients with radical cystectomy in Shanghai General Hospital during 2007 to 2018. Based on the results of proteomics sequencing from 9 pairs of MIBC tissue from Shanghai General Hospital, we focused on 13 immune-related differential expression proteins and their related genes. An immune-related prognostic signature (IRPS) was constructed according to Cancer Genome Atlas (TCGA) dataset. The IRPS was verified in ArrayExpress (E-MTAB-4321) cohort and Shanghai General Hospital (General) cohort, separately. A total of 1010 BCa patients were involved in the study, including 405 BCa patients in TCGA cohort, 476 BCa patients in E-MTAB-4321 cohort and 129 MIBC patients in General cohort.

Result

It can be indicated that high IRPS score was related to poor 5-year overall survival and disease-free survival. The IRPS score was also evaluated its immune infiltration. We found that the IRPS score was adversely associated with GZMB, IFN-γ, PD-1, PD-L1. Additionally, higher IRPS score was significantly associated with more M2 macrophage and resting mast cell infiltration.

Conclusion

The study revealed a novel BCa prognostic signature based on IRPS score, which may be useful for BCa immunotherapies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09783-y.

Noncoding RNA-mediated macrophage and cancer cell crosstalk in hepatocellular carcinoma

The tumor microenvironment (TME) is a well-recognized system that plays an essential role in tumor initiation, development, and progression. Intense intercellular communication between tumor cells and other cells (especially macrophages) occurs in the TME and is mediated by cell-to-cell contact and/or soluble messengers. Emerging evidence indicates that noncoding RNAs (ncRNAs) are critical regulators of the relationship between cells within the TME. In this review, we provide an update on the regulation of ncRNAs (primarily micro RNAs [miRNAs], long ncRNAs [lncRNAs], and circular RNAs [circRNAs]) in the crosstalk between macrophages and tumor cells in hepatocellular carcinoma (HCC). These ncRNAs are derived from macrophages or tumor cells and act as oncogenes or tumor suppressors, contributing to tumor progression not only by regulating the physiological and pathological processes of tumor cells but also by controlling macrophage infiltration, activation, polarization, and function. Herein, we also explore the options available for clinical therapeutic strategies targeting crosstalk-related ncRNAs to treat HCC. A better understanding of the relationship between macrophages and tumor cells mediated by ncRNAs will uncover new diagnostic biomarkers and pharmacological targets in cancer.

Characterizing the landscape of cervical squamous cell carcinoma immune microenvironment by integrating the single-cell transcriptomics and RNA-Seq

Background

Cervical squamous cell carcinoma (CSCC), caused by the infection of high‐risk human papillomavirus, is one of the most common malignancies in women worldwide.

Methods

RNA expression data, including those from the Cancer Genome Atlas, Gene Expression Omnibus, and Genotype‐Tissue Expression databases, were used to identify the expression of RNAs in normal and tumor tissue. Correlation analysis was performed to identify the immune‐related long noncoding RNAs (IRLs) and hypoxia‐related genes (IRHs) that can influence the activity of the immune system. Prognosis models of immune‐related RNAs (IRRs) were used to construct a coexpression network of the immune system. We identified the role of IRRs in immunotherapy by correlation analysis with immune checkpoint genes (ICGs). We then validated the expression data by integrating two single‐cell sequencing data sets of CSCC to identify the key immune features.

Results

In total, six immune‐related gene (IRG), four IRL, and five IRH signatures that can significantly influence the characteristics of the tumor immune microenvironment (TIME) were selected using machine learning methods. The expression level of ICGs was significantly upregulated in GZMB⁺CD8⁺ T‐cells and tumor‐associated macrophages (TAMs) in tumor tissues. TGFBI⁺ TAMs are a kind of blood‐derived monocyte‐derived M0‐like TAM linked to hypoxia and a poor prognosis. IFI30⁺ M1‐like TAMs participate in the process of immune‐regulation and showed a role in the promotion of CD8⁺ T‐cells and Type 1 T helper (Th1)/Th2 cells in the coexpression network, together with several IRLs, IRGs, and ICGs.

Conclusions

CD16⁺ monocyte‐derived IFI30⁺ TAMs participated in our coexpression network to regulate the TIME, showing the potential to be a novel immunotherapy target. The enrichment of M0‐like TAMs was associated with a worse prognosis in the high‐risk score group with IRH signatures. Remarkably, M0‐like TAMs in tumor tissues overexpressed TGFBI and were associated with several well‐known tumor‐proliferation pathways.

Harnessing anti-tumor and tumor-tropism functions of macrophages via nanotechnology for tumor immunotherapy

Reprogramming the immunosuppressive tumor microenvironment by modulating macrophages holds great promise in tumor immunotherapy. As a class of professional phagocytes and antigen-presenting cells in the innate immune system, macrophages can not only directly engulf and clear tumor cells, but also play roles in presenting tumor-specific antigen to initiate adaptive immunity. However, the tumor-associated macrophages (TAMs) usually display tumor-supportive M2 phenotype rather than anti-tumor M1 phenotype. They can support tumor cells to escape immunological surveillance, aggravate tumor progression, and impede tumor-specific T cell immunity. Although many TAMs-modulating agents have shown great success in therapy of multiple tumors, they face enormous challenges including poor tumor accumulation and off-target side effects. An alternative solution is the use of advanced nanostructures, which not only can deliver TAMs-modulating agents to augment therapeutic efficacy, but also can directly serve as modulators of TAMs. Another important strategy is the exploitation of macrophages and macrophage-derived components as tumor-targeting delivery vehicles. Herein, we summarize the recent advances in targeting and engineering macrophages for tumor immunotherapy, including (1) direct and indirect effects of macrophages on the augmentation of immunotherapy and (2) strategies for engineering macrophage-based drug carriers. The existing perspectives and challenges of macrophage-based tumor immunotherapies are also highlighted.

Nanostructured Titanium Implant Surface Facilitating Osseointegration from Protein Adsorption to Osteogenesis: The Example of TiO2 NTAs

Titanium implants have been widely applied in dentistry and orthopedics due to their biocompatibility and resistance to mechanical fatigue. TiO₂ nanotube arrays (TiO₂ NTAs) on titanium implant surfaces have exhibited excellent biocompatibility, bioactivity, and adjustability, which can significantly promote osseointegration and participate in its entire path. In this review, to give a comprehensive understanding of the osseointegration process, four stages have been divided according to pivotal biological processes, including protein adsorption, inflammatory cell adhesion/inflammatory response, additional relevant cell adhesion and angiogenesis/osteogenesis. The impact of TiO₂ NTAs on osseointegration is clarified in detail from the four stages. The nanotubular layer can manipulate the quantity, the species and the conformation of adsorbed protein. For inflammatory cells adhesion and inflammatory response, TiO₂ NTAs improve macrophage adhesion on the surface and induce M2-polarization. TiO₂ NTAs also facilitate the repairment-related cells adhesion and filopodia formation for additional relevant cells adhesion. In the angiogenesis and osteogenesis stage, TiO₂ NTAs show the ability to induce osteogenic differentiation and the potential for blood vessel formation. In the end, we propose the multi-dimensional regulation of TiO₂ NTAs on titanium implants to achieve highly efficient manipulation of osseointegration, which may provide views on the rational design and development of titanium implants.

Recent Advances of Autophagy in Non-Small Cell Lung Cancer: From Basic Mechanisms to Clinical Application

Lung cancer is characterized by the most common oncological disease and leading cause of cancer death worldwide, of which a group of subtypes known as non-small cell lung cancer (NSCLC) accounts for approximately 85%. In the past few decades, important progression in the therapies of NSCLC has enhanced our understanding of the biology and progression mechanisms of tumor. The application of immunotherapy and small molecule tyrosine kinase inhibitors has brought significant clinical benefits in certain patients. However, early metastasis and the emergence of resistance to antitumor therapy have resulted in the relatively low overall cure and survival rates for NSCLC. Autophagy is a conserved process that allows cells to recycle unused or damaged organelles and cellular components. It has been reported to be related to the progression of NSCLC and resistance to targeted therapy and cytotoxic chemotherapy. Therefore, autophagy is considered as a potential therapeutic target for NSCLC. Mounting results have been reported about the combination of tyrosine kinase inhibitors and inhibitors of autophagy in models of NSCLC. This review aims to provide a comprehensive review on the roles of autophagy in NSCLC, focusing on related clinical data of agents that regulate autophagy in NSCLC. Furthermore, this study will provide a theoretical basis for further improvement of autophagy-based cancer therapy.

Advanced Biomaterials for Cell-Specific Modulation and Restore of Cancer Immunotherapy

The past decade has witnessed the explosive development of cancer immunotherapies. Nevertheless, low immunogenicity, limited specificity, poor delivery efficiency, and off-target side effects remain to be the major limitations for broad implementation of cancer immunotherapies to patient bedside. Encouragingly, advanced biomaterials offering cell-specific modulation of immunological cues bring new solutions for improving the therapeutic efficacy while relieving side effect risks. In this review, focus is given on how functional biomaterials can enable cell-specific modulation of cancer immunotherapy within the cancer-immune cycle, with particular emphasis on antigen-presenting cells (APCs), T cells, and tumor microenvironment (TME)-resident cells. By reviewing the current progress in biomaterial-based cancer immunotherapy, here the aim is to provide a better understanding of biomaterials' role in targeting modulation of antitumor immunity step-by-step and guidelines for rationally developing targeting biomaterials for more personalized cancer immunotherapy. Moreover, the current challenge and future perspective regarding the potential application and clinical translation will also be discussed.

Enhancing cancer chemo-immunotherapy by biomimetic nanogel with tumor targeting capacity and rapid drug-releasing in tumor microenvironment

In the development of chemo-immunotherapy, many efforts have been focusing on designing suitable carriers to realize the co-delivery of chemotherapeutic and immunotherapeutic with different physicochemical properties and mechanisms of action. Besides, rapid drug release at the tumor site with minimal drug degradation is also essential to facilitate the antitumor effect in a short time. Here, we reported a cancer cell membrane-coated pH-responsive nanogel (NG@M) to co-deliver chemotherapeutic paclitaxel (PTX) and immunotherapeutic agent interleukin-2 (IL-2) under mild conditions for combinational treatment of triple-negative breast cancer. In the designed nanogels, the synthetic copolymer PDEA-co-HP-β-cyclodextrin-co-Pluronic F127 and charge reversible polymer dimethylmaleic anhydride-modified polyethyleneimine endowed nanogels with excellent drug-loading capacity and rapid responsive drug-releasing behavior under acidic tumor microenvironment. Benefited from tumor homologous targeting capacity, NG@M exhibited 4.59-fold higher accumulation at the homologous tumor site than heterologous cancer cell membrane-coated NG. Rapidly released PTX and IL-2 enhanced the maturation of dendritic cells and quickly activated the antitumor immune response in situ, followed by prompted infiltration of immune effector cells. By the combined chemo-immunotherapy, enhanced antitumor effect and efficient pulmonary metastasis inhibition were achieved with a prolonged median survival rate (39 days).

Ratiometric afterglow luminescent nanoplatform enables reliable quantification and molecular imaging

Afterglow luminescence is an internal luminescence pathway that occurs after photo-excitation, holds great promise for non-background molecular imaging in vivo, but suffer from poor quantitative ability owing to luminescent attenuation over time. Moreover, the inert structure and insufficient reactive sites of current afterglow materials make it hard to design activatable afterglow probes for specific detection. Here, we report a ratiometric afterglow luminescent nanoplatform to customize various activatable afterglow probes for reliable quantification and molecular imaging of specific analytes, such as NO, ONOO⁻ or pH. Notably, these afterglow probes can not only address the attenuation of afterglow intensity and eliminate the interference of factors (e.g., laser power, irradiation time, and exposure time), but also significantly improve the imaging reliability in vivo and signal-to-background ratios (~1200-fold), both of which enable more reliable quantitative analysis in biological systems. Moreover, as a proof-of-concept, we successfully design an NO-responsive ratiometric afterglow nanoprobe, RAN1. This nanoprobe can monitor the fluctuations of intratumoral NO, as a biomarker of macrophage polarization, making it possible to real-time dynamically evaluate the degree cancer immunotherapy, which provides a reliable parameter to predict the immunotherapeutic effect.

Afterglow luminescence is promising for non-background molecular imaging in vivo. Here the authors report a ratiometric afterglow luminescent nanoplatform to generate activatable afterglow probes for quantification of specific analytes including NO.

Lucanthone Targets Lysosomes to Perturb Glioma Proliferation, Chemoresistance and Stemness, and Slows Tumor Growth In Vivo

Glioblastoma is the most common and aggressive primary brain tumor in adults. Median survival time remains at 16-20 months despite multimodal treatment with surgical resection, radiation, temozolomide and tumor-treating fields therapy. After genotoxic stress glioma cells initiate cytoprotective autophagy, which contributes to treatment resistance, limiting the efficacy of these therapies and providing an avenue for glioma recurrence. Antagonism of autophagy steps has recently gained attention as it may enhance the efficacy of classical chemotherapies and newer immune-stimulating therapies. The modulation of autophagy in the clinic is limited by the low potency of common autophagy inhibitors and the inability of newer ones to cross the blood-brain barrier. Herein, we leverage lucanthone, an anti-schistosomal agent which crosses the blood-brain barrier and was recently reported to act as an autophagy inhibitor in breast cancer cells. Our studies show that lucanthone was toxic to glioma cells by inhibiting autophagy. It enhanced anti-glioma temozolomide (TMZ) efficacy at sub-cytotoxic concentrations, and suppressed the growth of stem-like glioma cells and temozolomide-resistant glioma stem cells. In vivo lucanthone slowed tumor growth: reduced numbers of Olig2+ glioma cells, normalized tumor vasculature, and reduced tumor hypoxia. We propose that lucanthone may serve to perturb a mechanism of temozolomide resistance and allow for successful treatment of TMZ-resistant glioblastoma.

Nanoparticle based medicines: approaches for evading and manipulating the mononuclear phagocyte system and potential for clinical translation

For decades, nanomedicines have been reported as a potential means to overcome the limitations of conventional drug delivery systems by reducing side effects, toxicity and the non-ideal pharmacokinetic behaviour typically exhibited by small molecule drugs. However, upon administration many nanoparticles prompt induction of host inflammatory responses due to recognition and uptake by macrophages, eliminating up to 95% of the administered dose. While significant advances in nanoparticle engineering and consequent therapeutic efficacy have been made, it is becoming clear that nanoparticle recognition by the mononuclear phagocyte system (MPS) poses an impassable junction in the current framework of nanoparticle development. Hence, this has negative consequences on the clinical translation of nanotechnology with respect to therapeutic efficacy, systemic toxicity and economic benefit. In order to improve the translation of nanomedicines from bench-to-bedside, there is a requirement to either modify nanomedicines in terms of how they interact with intrinsic processes in the body, or modulate the body to be more accommodating for nanomedicine treatments. Here we provide an overview of the current standard for design elements of nanoparticles, as well as factors to consider when producing nanomedicines that have minimal MPS-nanoparticle interactions; we explore this landscape across the cellular to tissue and organ levels. Further, rather than designing materials to suit the body, a growing research niche involves modulating biological responses to administered nanomaterials. We here discuss how developing strategic methods of MPS 'pre-conditioning' with small molecule or biological drugs, as well as implementing strategic dosing regimens, such as 'decoy' nanoparticles, is essential to increasing nanoparticle therapeutic efficacy. By adopting such a perspective, we hope to highlight the increasing trends in research dedicated to improving nanomedicine translation, and subsequently making a positive clinical impact.

Identification of a Ferroptosis-Related Prognostic Gene PTGS2 Based on Risk Modeling and Immune Microenvironment of Early-Stage Cervical Cancer

Background

Cervical cancer (CC) has long been a concern, as a gynecological cancer type of high-risk. At present, there are few studies on the early detection of CC at the genetic level. The breakthrough is to recognize CC patients tending to have a worse prognosis by checking the expression pattern of ferroptosis-related genes, which enjoy a great potential of being applied to cancer treatment.

Methods

Data used in this study was obtained from a series of public online databases, integrated with ferroptosis-related gene collection stored from the FerrDb database and GeneCards database. The least absolute shrinkage and selection operator- (LASSO-) penalized analysis was taken for modeling, and before, univariate Cox regression analysis got done to shrink the candidates' range. Several analyses were made for the evaluation of the efficacy of the new model, based on CC patients' overall survival (OS). Tumor microenvironment- (TME-) related analyses were conducted by various algorithms on different populations, comprising CIBERSORT, ssGSEA, XCELL, etc. Nonnegative matrix factorization (NMF) clustering got applied to find that ferroptosis-marker genes affect prognosis more than "driver" and "suppressor". Hub-gene PTGS2 was screened out by protein-protein interaction analysis and real-time qPCR after ferroptosis induction, and ELISA was conducted for further verification on the correlation between ferroptosis and M1 polarization.

Results

The twenty-five ferroptosis-related genes model can estimate the prognosis of patients independently of other clinical factors, and the low-risk score group shows higher expression of immune-enhancing cells, noteworthily for M1 macrophages. It is experimentally validated that the M1 marker TNF-α significantly increased after coculturing M1 macrophages and SiHa cells processed with ferroptosis inductor before. The key gene to the model, PTGS2, presented to be a risk factor in cervical cancer, and its low-expression group has stronger immune activity and higher tumor mutation burden, with the significantly highly mutated gene TENM2 in it showing high drug sensitivity and neoantigen for patients with its mutant-type. Meanwhile, it influences macrophage polarization.

Conclusion

Prognosis of early-stage cervical cancer patients can be exactly predicted on ferroptosis-related genes. Among model genes, PTGS2 may have a major impact by affecting macrophage polarization and mutation effects.

The Mechanism of the Development of Macrophage Tolerance in Tumor Microenvironment

Bacteria forming the resident microbiome of the tumor are an integral component of its microenvironment. The interaction of the tumor microbiome with the tumor or tumor stromal cells is not well understood. We hypothesized that bacteria in the tumor microenvironment induce macrophage tolerance. Macrophage tolerance is a phenomenon of macrophage inability to respond to a repetitive inflammatory stimulus, which leads to a loss of cytotoxic activity. We studied the development of macrophage tolerance under the influence of bacteria and cytokines of the tumor microenvironment in vitro. It was found that the macrophage tolerance in the tumor stroma can develop in response to bacterial cell wall components and inflammatory factors. The acquired tolerance is inability of macrophages to produce proinflammatory cytokines TNFα, IL-1β, and MCP-1 and activation of the production of immunosuppressive IL-10.

Engineering in vitro immune-competent tissue models for testing and evaluation of therapeutics

Advances in 3D cell culture, microscale fluidic control, and cellular analysis have enabled the development of more physiologically-relevant engineered models of human organs with precise control of the cellular microenvironment. Engineered models have been used successfully to answer fundamental biological questions and to screen therapeutics, but these often neglect key elements of the immune system. There are immune elements in every tissue that contribute to healthy and diseased states. Including immune function will be essential for effective preclinical testing of therapeutics for inflammatory and immune-modulated diseases. In this review, we first discuss the key components to consider in designing engineered immune-competent models in terms of physical, chemical, and biological cues. Next, we review recent applications of models of immunity for screening therapeutics for cancer, preclinical evaluation of engineered T cells, modeling autoimmunity, and screening vaccine efficacy. Future work is needed to further recapitulate immune responses in engineered models for the most informative therapeutic screening and evaluation.

The immune microenvironment in cartilage injury and repair

The ability of articular cartilage to repair itself is limited because it lacks blood vessels, nerves, and lymph tissue. Once damaged, it can lead to joint swelling and pain, accelerating the progression of osteoarthritis. To date, complete regeneration of hyaline cartilage exhibiting mechanical properties remains an elusive goal, despite the many available technologies. The inflammatory milieu created by cartilage damage is critical for chondrocyte death and hypertrophy, extracellular matrix breakdown, ectopic bone formation, and progression of cartilage injury to osteoarthritis. In the inflammatory microenvironment, mesenchymal stem cells (MSCs) undergo aberrant differentiation, and chondrocytes begin to convert or dedifferentiate into cells with a fibroblast phenotype, thereby resulting in fibrocartilage with poor mechanical qualities. All these factors suggest that inflammatory problems may be a major stumbling block to cartilage repair. To produce a milieu conducive to cartilage repair, multi-dimensional management of the joint inflammatory microenvironment in place and time is required. Therefore, this calls for elucidation of the immune microenvironment of cartilage repair after injury. This review provides a brief overview of: (1) the pathogenesis of cartilage injury; (2) immune cells in cartilage injury and repair; (3) effects of inflammatory cytokines on cartilage repair; (4) clinical strategies for treating cartilage defects; and (5) strategies for targeted immunoregulation in cartilage repair. STATEMENT OF SIGNIFICANCE: Immune response is increasingly considered the key factor affecting cartilage repair. It has both negative and positive regulatory effects on the process of regeneration and repair. Proinflammatory factors are secreted in large numbers, and necrotic cartilage is removed. During the repair period, immune cells can secrete anti-inflammatory factors and chondrogenic cytokines, which can inhibit inflammation and promote cartilage repair. However, inflammatory factors persist, which accelerate the degradation of the cartilage matrix. Furthermore, in an inflammatory microenvironment, MSCs undergo abnormal differentiation, and chondrocytes begin to transform or dedifferentiate into fibroblast-like cells, forming fibrocartilage with poor mechanical properties. Consequently, cartilage regeneration requires multi-dimensional regulation of the joint inflammatory microenvironment in space and time to make it conducive to cartilage regeneration.

Nano-ultrasonic Contrast Agent for Chemoimmunotherapy of Breast Cancer by Immune Metabolism Reprogramming and Tumor Autophagy

The functional status of innate immune cells is a considerable determinant of effective antitumor immune response. However, the triple-negative breast cancer tumor microenvironment with high lactic acid metabolism and high antioxidant levels limits immune cell survival, differentiation, and function. Here, we determine that the tumor microenvironment-responsive nano-ultrasonic contrast agent Pt(IV)/CQ/PFH NPs-^DPPA-1 boosts the ratio of mature dendritic cells (mDCs) and proinflammatory macrophages by reprogramming the metabolism of immature DCs (iDCs) and tumor-associated macrophages (TAMs). Specifically, platinum(IV) in cancer cells or iDCs was reduced to cisplatin, which can increase the intracellular content of ROS and therefore enhance the ratio of mDCs and apoptotic tumor cells. Meanwhile, chloroquine (CQ) released from nanoparticles (NPs) minimizes protective autophagy caused by cisplatin in tumor cells and reprograms the metabolism of TAMs to enhance the proportion of proinflammatory macrophages, achieving a superior synergistic effect of chemoimmunotherapy combined with Pt(IV) and anti-PD-L1 peptide (^DPPA-1). Furthermore, perfluorohexane (PFH) in NPs realizes monitoring treatment corresponding to ultrasound. Collectively, the nano-ultrasonic contrast agent supports a candidate for monitoring treatment and augmenting antitumor chemoimmunotherapy by suppressing tumor cell autophagy and reprogramming immunocyte metabolism.

Comprehensive Analysis of the Immune Microenvironment in Checkpoint Inhibitor Pneumonitis

Background

While immune checkpoint inhibitors (ICIs) are a beacon of hope for non-small cell lung cancer (NSCLC) patients, they can also cause adverse events, including checkpoint inhibitor pneumonitis (CIP). Research shows that the inflammatory immune microenvironment plays a vital role in the development of CIP. However, the role of the immune microenvironment (IME) in CIP is still unclear.

Methods

We collected a cohort of NSCLC patients treated with ICIs that included eight individuals with CIP (CIP group) and 29 individuals without CIP (Control group). CIBERSORT and the xCell algorithm were used to evaluate the proportion of immune cells. Gene set enrichment analysis (GSEA) and single-sample GSEA (ssGSEA) were used to evaluate pathway activity. The ridge regression algorithm was used to analyze drug sensitivity.

Results

CIBERSORT showed significantly upregulated memory B cells, CD8+ T cells, and M1 Macrophages in the CIP group. The number of memory resting CD4+ T cells and resting NK cells in the CIP group was also significantly lower than in the Control group. The XCell analysis showed a higher proportion of Class-switched memory B-cells and M1 Macrophages in the CIP group. Pathway analysis showed that the CIP group had high activity in their immune and inflammatory response pathways and low activity in their immune exhaustion related pathway.

Conclusions

In this study, we researched CIP patients who after ICIs treatment developed an inflammatory IME, which is characterized by significantly increased activated immune cells and expression of inflammatory molecules, as well as downregulated immunosuppressive lymphocytes and signaling pathways. The goal was to develop theoretical guidance for clinical guidelines for the treatment of CIP in the future.

Repolarization of Unbalanced Macrophages: Unmet Medical Need in Chronic Inflammation and Cancer

Monocytes and their tissue counterpart macrophages (MP) constitute the front line of the immune system. Indeed, they are able to rapidly and efficiently detect both external and internal danger signals, thereby activating the immune system to eradicate the disturbing biological, chemical, or physical agents. They are also in charge of the control of the immune response and account for the repair of the damaged tissues, eventually restoring tissue homeostasis. The balance between these dual activities must be thoroughly controlled in space and time. Any sustained unbalanced response of MP leads to pathological disorders, such as chronic inflammation, or favors cancer development and progression. In this review, we take advantage of our expertise in chronic inflammation, especially in rheumatoid arthritis, and in cancer, to highlight the pivotal role of MP in the physiopathology of these disorders and to emphasize the repolarization of unbalanced MP as a promising therapeutic strategy to control these diseases.

Therapeutic exosomal vaccine for enhanced cancer immunotherapy by mediating tumor microenvironment

Tumor immunotherapy has been convincingly demonstrated as a feasible approach for treating cancers. Although promising, the immunosuppressive tumor microenvironment (TME) has been recognized as a major obstacle in tumor immunotherapy. It is highly desirable to release an immunosuppressive "brake" for improving cancer immunotherapy. Among tumor-infiltrated immune cells, tumor-associated macrophages (TAMs) play an important role in the growth, invasion, and metastasis of tumors. The polarization of TAMs (M2) into the M1 type can alleviate the immunosuppression of the TME and enhance the effect of immunotherapy. Inspired by this, we constructed a therapeutic exosomal vaccine from antigen-stimulated M1-type macrophages (M1_OVA-Exos). M1_OVA-Exos are capable of polarizing TAMs into M1 type through downregulation of the Wnt signaling pathway. Mediating the TME further activates the immune response and inhibits tumor growth and metastasis via the exosomal vaccine. Our study provides a new strategy for the polarization of TAMs, which augments cancer vaccine therapy efficacy.

Myeloid-Derived Suppressor Cells in Solid Tumors

Myeloid-derived suppressor cells (MDSCs) are one of the main suppressive cell population of the immune system. They play a pivotal role in the establishment of the tumor microenvironment (TME). In the context of cancers or other pathological conditions, MDSCs can differentiate, expand, and migrate in large quantities during circulation, inhibiting the cytotoxic functions of T cells and NK cells. This process is regulated by ROS, iNOS/NO, arginase-1, and multiple soluble cytokines. The definition of MDSCs and their phenotypes in humans are not as well represented as in other organisms such as mice, owing to the absence of the cognate molecule. However, a comprehensive understanding of the differences between different species and subsets will be beneficial for clarifying the immunosuppressive properties and potential clinical values of these cells during tumor progression. Recently, experimental evidence and clinical investigations have demonstrated that MDSCs have a close relationship with poor prognosis and drug resistance, which is considered to be a leading marker for practical applications and therapeutic methods. In this review, we summarize the remarkable position of MDSCs in solid tumors, explain their classifications in different models, and introduce new treatment approaches to target MDSCs to better understand the advancement of new approaches to cancer treatment.

Inhibition of high-fat diet-induced obesity via reduction of ER-resident protein Nogo occurs through multiple mechanisms

Obesity is a risk factor for insulin resistance, type 2 diabetes, and cardiovascular diseases. Reticulon-4 (Nogo) is an endoplasmic reticulum–resident protein with unclear functions in obesity. Herein, we investigated the effect of Nogo on obesity and associated metabolic disorders. Human serum samples were collected to explore the relationship between circulating Nogo-B and body mass index value. Nogo-deficient and WT littermate control mice were fed normal chow or high-fat diet (HFD) for 14 weeks, and HFD-induced obese C57BL/6J mice were injected scrambled or Nogo siRNA for 2 weeks. We found that in human and mouse serum, Nogo-B was positively correlated to body mass index/bodyweight and lipid profiles. Reduced Nogo (by genetic deletion or siRNA transfection) protected mice against HFD-induced obesity and related metabolic disorders. We demonstrate that Nogo deficiency reversed HFD-induced whitening of brown adipose tissue, thereby increasing thermogenesis. It also ameliorated lipid accumulation in tissues by activating the adiponectin–adiponectin receptor 1–AMP-activated kinase α signaling axis. Finally, Nogo deficiency potently reduced HFD-induced serum proinflammatory cytokines and infiltration of macrophages into metabolic organs, which is related to enhanced NF-κB p65 degradation via the lysosome pathway. Collectively, our study suggests that reduced levels of Nogo protect mice against HFD-induced obesity by increasing thermogenesis and energy metabolism while inhibiting NF-κB-mediated inflammation. Our results indicate that inhibition of Nogo may be a potential strategy for obesity treatment.

Precise Diabetic Wound Therapy: PLS Nanospheres Eliminate Senescent Cells via DPP4 Targeting and PARP1 Activation

Diabetic ulcers, a difficult problem faced by clinicians, are strongly associated with an increase in cellular senescence. Few empirical studies have focused on exploring a targeted strategy to cure diabetic wounds by eliminating senescent fibroblasts (SFs) and reducing side effects. In this study, poly-l-lysine/sodium alginate (PLS) is modified with talabostat (PT100) and encapsulates a PARP1 plasmid (PARP1@PLS-PT100) for delivery to target the dipeptidyl peptidase 4 (DPP4) receptor and eliminate SFs. PARP1@PLS-PT100 releases encapsulated plasmids, displaying high selectivity for SFs over normal fibroblasts by targeting the DPP4 receptor, decreasing senescence-associated secretory phenotypes (SASPs), and stimulating the secretion of anti-inflammatory factors. Furthermore, the increased apoptosis of SFs and the disappearance of cellular senescence alleviates SASPs, accelerates re-epithelialization and collagen deposition, and significantly induces macrophage M2 polarization, which mediates tissue repair and the inflammatory response. This innovative strategy has revealed the previously undefined role of PARP1@PLS-PT100 in promoting diabetic wound healing, suggesting its therapeutic potential in refractory wound repair.

Aerobic glycolysis is important for zebrafish larval wound closure and tail regeneration

The underlying mechanisms of appendage regeneration remain largely unknown and uncovering these mechanisms in capable organisms has far-reaching implications for potential treatments in humans. Recent studies implicate a requirement for metabolic reprogramming reminiscent of the Warburg effect during successful appendage and organ regeneration. As changes are thus predicted to be highly dynamic, methods permitting direct, real-time visualisation of metabolites at the tissue and organismal level would offer a significant advance in defining the influence of metabolism on regeneration and healing. We sought to examine whether glycolytic activity was altered during larval fin regeneration, utilising the genetically encoded biosensor, Laconic, enabling the spatiotemporal assessment of lactate levels in living zebrafish. We present evidence for a rapid increase in lactate levels within min following injury, with a role of aerobic glycolysis in actomyosin contraction and wound closure. We also find a second wave of lactate production, associated with overall larval tail regeneration. Chemical inhibition of glycolysis attenuates both the contraction of the wound and regrowth of tissue following tail amputation, suggesting aerobic glycolysis is necessary at two distinct stages of regeneration.

Novel polysaccharide building hybrid nanoparticles: remodelling TAMs to target ERα-positive breast cancer

With the increasing number of oncology patients and the use of chemotherapeutic agents, tumour multidrug resistance is becoming more and more prevalent. The search for new tumour treatment strategies to overcome tumour multidrug resistance is urgent. In this study, we designed GSH and ROS dual-responsive tumour-associated macrophages (TAMs)-targeted nanoparticles (NPs) for the co-delivery of the clinical first-line anti-breast cancer chemotherapy drug paclitaxel (PTX) and baicalin (Bai), which re-educates TAMs to alter their phenotype. We synthesised oligohyaluronic acid-mannose-folic acid (oHA-Man-FA, HMF) and astragalus polysaccharide-dithiodipropionic acid-paeoniflorol (APS-S-Pae, ASP), two hybrid materials that can self-assemble in water to form hybrid nanoparticles (HP-NPs) co-loaded with paclitaxel and baicalin (HP-NPs@PTX/Bai). The experimental results show that our designed hybrid nanoparticles can be specifically released in the tumour microenvironment and deliver the antitumor drug PTX as well as Bai, which reshapes the phenotype of TAMs, to the tumour site. The hybrid nanoparticles not only effectively re-educated TAMs from M2 TAM to M1 TAM, but also ameliorated the cytotoxic side effects caused by free PTX and provided better tumour suppression than free PTX and HP.

Remodeling Macrophages by an Iron Nanotrap for Tumor Growth Suppression

Tumor-associated macrophages (TAMs) that infiltrate in most tumor tissues are closely correlated with proliferation and metastasis of tumor cells. Immunomodulation of TAMs from pro-tumorigenic M2 phenotype to anti-tumorigenic M1 phenotype is crucial for oncotherapy. Herein, an iron nanotrap was utilized to remodel TAMs for tumor growth inhibition. In the formulation, the ultrasmall nanotrap could capture and targetedly transport endogenous iron into TAMs even inside the tumor. Upon exposing to the lysosomal acidic conditions and intracellular H₂O₂, iron was released from the nanotrap and produced the generation of oxidative stress, which could reprogram TAMs. The activated M1 macrophages could induce immune responses and suppress tumor growth ultimately. Meanwhile, this metal-free nanotrap with degradability by H₂O₂ possessed favorable biocompatibility. Our work would present potential opportunities of utilizing endogenous substances for secure treatment of various diseases.

TFEB Dependent Autophagy-Lysosomal Pathway: An Emerging Pharmacological Target in Sepsis

Sepsis is a life-threatening syndrome induced by aberrant host response towards infection. The autophagy-lysosomal pathway (ALP) plays a fundamental role in maintaining cellular homeostasis and conferring organ protection. However, this pathway is often impaired in sepsis, resulting in dysregulated host response and organ dysfunction. Transcription factor EB (TFEB) is a master modulator of the ALP. TFEB promotes both autophagy and lysosomal biogenesis via transcriptional regulation of target genes bearing the coordinated lysosomal expression and regulation (CLEAR) motif. Recently, increasing evidences have linked TFEB and the TFEB dependent ALP with pathogenetic mechanisms and therapeutic implications in sepsis. Therefore, this review describes the existed knowledge about the mechanisms of TFEB activation in regulating the ALP and the evidences of their protection against sepsis, such as immune modulation and organ protection. In addition, TFEB activators with diversified pharmacological targets are summarized, along with recent advances of their potential therapeutic applications in treating sepsis.

Inhibiting autophagy flux and DNA repair of tumor cells to boost radiotherapy of orthotopic glioblastoma

Radio-resistance of glioblastoma (GBM) remains a leading cause of radiotherapy failure because of the protective autophagy induced by X-Ray irradiation and tumor cells' strong capability of repairing damaged DNA. It is of great importance to overcome the radio-resistance for improving the efficacy of radiotherapy. Herein, we report the novel mechanism of core-shell copper selenide coated gold nanoparticles (Au@Cu_2-xSe NPs) inhibiting the protective autophagy and DNA repair of tumor cells to drastically boost the radiotherapy efficacy of glioblastoma. We reveal that the core-shell Au@Cu_2-xSe NPs can inhibit the autophagy flux by effectively alkalizing lysosomes. They can increase the SQSTM1/p62 protein levels of tumor cells without influencing their mRNA. We also reveal that Au@Cu_2-xSe NPs can increase the ubiquitination of DNA repair protein Rad51, and promote the degradation of Rad51 by proteasomes to prevent the DNA repair. The simultaneous inhibition of protective autophagy and DNA repair significantly suppress the growth of orthotopic GBM by using radiotherapy and our novel Au@Cu_2-xSe NPs. Our work provides a new insight and paradigm to significantly improve the efficacy of radiotherapy by rationally designing theranostic nano-agents to simultaneously inhibit protective autophagy and DNA repair of tumor cells.

Antimalarials may reduce cancer risk in patients with systemic lupus erythematosus: a systematic review and meta-analysis of prospective studies

OBJECTIVE

To investigate the effect of antimalarials on cancer risk in patients with systemic lupus erythematosus (SLE).

METHODS

PubMed, EMBASE, Web of Science, and the Cochrane Library were searched from their inception to October 3, 2020. Relative risk (RR) with 95% confidence intervals (CI) was used to evaluate the results. Subgroup analyses were used to assess heterogeneity. A funnel plot was used to explore publication bias. STATA was applied for all analyses.

RESULTS

A total of nine studies consisted of four nested case-control, two case-cohort and three cohort studies were included. The results showed that antimalarials might reduce the risk of cancer in SLE (RR = 0.68, 95%CI: 0.55-0.85). In the subgroup analysis of four nested case-control and two case-cohort studies, the pooled RR was estimated as 0.69 (95% CI: 0.60-0.80). In four studies about hydroxychloroquine, the pooled RR was estimated as 0.70 (95% CI: 0.53-0.93). Antimalarials might reduce the risk of cancer in SLE among the Asian population (RR = 0.66; 95% CI: 0.49-0.88) (I2 = 43.1%, p = .173). And the consistent result was also found in SLE from multiple centres (RR = 0.72; 95%CI: 0.60-0.87) (I2 = 0%, p = .671). On disease course- and comorbidities-matched studies, the pooled RRs were 0.69 (95% CI: 0.52-0.93) and 0.59 (95% CI: 0.46-0.75), respectively.

CONCLUSION

Results of this meta-analysis showed that antimalarial drugs might be protective factors for cancer in SLE. Hydroxychloroquine might be a protective factor for cancer in SLE patients.KEY MESSAGESAntimalarials might be protective factors for cancer in SLE.Hydroxychloroquine might be a protective factor for cancer in SLE patients.The first article to perform the meta-analysis of antimalarial drugs on the risk of cancer in SLE patients.

Autophagy in Xp11 translocation renal cell carcinoma: from bench to bedside

Xp11 translocation renal cell carcinoma (tRCC) characterized by the rearrangement of the TFE3 is recently identified as a unique subtype of RCC that urgently requires effective prevention and treatment strategies. Therefore, determining suitable therapeutic targets and fully understanding the biological significance of tRCC is essential. The importance of autophagy is increasingly acknowledged because it shows carcinogenic activity or suppressor effect. Autophagy is a physiological cellular process critical to maintaining cell homeostasis, which is involved in the lysosomal degradation of cytoplasmic organelles and macromolecules via the lysosomal pathway, suggesting that targeting autophagy is a potential therapeutic approach for cancer therapies. However, the underlying mechanism of autophagy in tRCC is still ambiguous. In this review, we summarize the autophagy-related signaling pathways associated with tRCC. Moreover, we examine the roles of autophagy and the immune response in tumorigenesis and investigate how these factors interact to facilitate or prevent tumorigenesis. Besides, we review the findings regarding the treatment of tRCC via induction or inhibition of autophagy. Hopefully, this study will shed some light on the functions and implications of autophagy and emphasize its role as a potential molecular target for therapeutic intervention in tRCC.

[Regulatory mechanism of interferon regulatory factor 1 by α-synuclein in mouse Parkinson's disease model]

OBJECTIVE

To investigate the molecular mechanism by which α-synuclein (α-Syn) regulates interferon regulatory factor 1 (IRF-1) expression.

METHODS

SH-SY5Y cells overexpressing α-Syn and transgenic mouse model carrying human α-Syn gene with A53T mutation (3 and 6 months old) were examined for IRF-1 mRNA and protein expressions using real-time PCR and Western blotting, respectively. The subcellular localization of IRF-1 was determined with immunofluorescence staining and cytoplasmic/nuclear protein isolation. The optimal concentrations of the proteasome inhibitor MG132 (0.01-2.0 μmol/L) and lysosomal inhibitor chloroquine (5-200 μmol/L) for treatment of SH-SY5Y cells for 24 h were determined by examining the cell viability. SH-SY5Y cells were treated with 0.2 μmol/L MG132 and 30 μmol/L chloroquine for 24 h (the maximum dose that did not cause cell damage), and the changes of IRF-1 protein expressions was analyzed. The effects of α-Syn on MDM2 protein expression and IRF-1 ubiquitylation were analyzed using Western blotting and ubiquitylation assay.

RESULTS

α-Syn overexpression did not affect the mRNA level of IRF-1 but significantly increased its protein level (P < 0.01). In α-Synoverexpressing SH-SY5Y cells, IRF-1 translocation was observed from the cytoplasm to the nucleus (P < 0.001). Treatment of the cells with 0.2 μmol/L MG132 significantly aggravated α-Syn-induced increase of IRF-1 protein expression (P < 0.01) while 30 μmol/L chloroquine produced no significant changes in IRF-1 level. α-Syn overexpression caused an obvious decrease of MDM2 protein level and further inhibited the ubiquitylation of IRF-1 (P < 0.01).

CONCLUSION

α-Syn blocks MDM2-mediated ubiquitylation of IRF-1 through ubiquitin proteasome pathway, thereby enhancing IRF-1 protein expression.

Reeducating Tumor-Associated Macrophages Using CpG@Au Nanocomposites to Modulate Immunosuppressive Microenvironment for Improved Radio-Immunotherapy

With the recent success of immune checkpoint blockade (ICB) in cancer immunotherapy, there has been renewed interest in evaluating the combination of ICB inhibitors with radiotherapy (RT) in clinical trials in view of the localized RT-initiated vaccination effect, which can be augmented further by systemic immune-stimulating agents. Unfortunately, traditional RT/ICB accompanies severe toxicity from high-dose ionizing irradiation and low response rate from RT-aggravated immunosuppression, among which M2-type tumor-associated macrophages (TAMs) play an important role. Herein, CpG-decorated gold (Au) nanoparticles (CpG@Au NPs) were fabricated to improve the RT/ICB efficacy by immune modulation under low-dose X-ray exposure, where Au NPs served as radioenhancers to minimize the radiotoxicity, and yet acted as nanocarriers to deliver CpG, a toll-like receptor 9 agonist, to re-educate immunosuppressive M2 TAMs to immunostimulatory M1 counterparts, thus arousing innate immunity and meanwhile priming T cell activation. When combined with an anti-programmed death 1 antibody, irradiated CpG@Au led to consistent abscopal responses that efficiently suppressed distant tumors in a bilateral GL261 tumor-bearing model. This work thus demonstrates that CpG@Au-mediated macrophage reeducation could efficiently modulate the tumor-immune microenvironment for synergistic RT/ICB.

Advances in plant-derived natural products for antitumor immunotherapy

In recent years, immunotherapy has emerged as a novel antitumor strategy in addition to traditional surgery, radiotherapy and chemotherapy. It uniquely focuses on immune cells and immunomodulators in the tumor microenvironment and helps eliminate tumors at the root by rebuilding the immune system. Despite remarkable breakthroughs, cancer immunotherapy still faces many challenges: lack of predictable and prognostic biomarkers, adverse side effects, acquired treatment resistance, high costs, etc. Therefore, more efficacious and efficient, safer and cheaper antitumor immunomodulatory drugs have become an urgent requirement. For decades, plant-derived natural products obtained from land and sea have provided the most important source for the development of antitumor drugs. Currently, more attention is being paid to the discovery of potential cancer immunotherapy modulators from plant-derived natural products, such as polysaccharides, phenols, terpenoids, quinones and alkaloids. Some of these agents have outstanding advantages of multitargeting and low side effects and low cost compared to conventional immunotherapeutic agents. We intend to summarize the progress of comprehensive research on these plant-derived natural products and their derivatives and discuss their possible mechanisms in regulating the immune system and their efficacy as monotherapies or in combination with regular chemotherapeutic agents.

Recent advancement on development of drug-induced macrophage polarization in control of human diseases

Macrophages, an important part of human immune system, possess a high plasticity and heterogeneity (macrophage polarization) as classically activated macrophages (M1) and alternatively activated macrophages (M2), which exert pro-inflammatory/anti-tumor and anti-inflammatory/pro-tumor effects, respectively. Thus, drug development in induction of macrophage polarization could be used to treat different human diseases. This review summarizes the recent advancement on modulation of macrophage polarization and its related molecular mechanisms induced by a number of agents. Research on the anti-inflammatory drugs to regulate the macrophage polarization accounts for a large proportion in the field and types of diseases investigated could include atherosclerosis, enteritis, nephritis, and the nervous system and skeletal diseases, while study of the anti-tumor agents to modify macrophage polarization is a novel area of research. Future study of the molecular mechanisms by which the different agents regulate the macrophage polarization could lead to an effective control of various human diseases, including inflammation and cancers.

Developing a Novel Indium(III) Agent Based on Liposomes to Overcome Cisplatin-Induced Resistance in Breast Cancer by Multitargeting the Tumor Microenvironment Components

To overcome the resistance of cancer cells to platinum-based drugs and effectively suppress tumor growth, we developed a novel indium (In) agent based on liposomes (Lips). Thus, we not only obtained an In(III) thiosemicarbazone agent (5b) with remarkable cytotoxicity by optimizing a series of In(III) thiosemicarbazone agents (1b-5b) but also successfully constructed a novel 5b-loaded Lip (5b-Lip) delivery system. Importantly, in vitro and in vivo results revealed that 5b/5b-Lip overcame the tumor cell resistance and effectively inhibited MCF-7/DDP tumor growth. In addition, Lips improved the intracellular accumulation of 5b. We also confirmed the mechanism by which 5b/5b-Lip overcomes breast cancer cell resistance. 5b/5b-Lip cannot act against DNA in cancer cells but attacks the two cell components in the tumor microenvironment, namely, by inducing apoptosis and lethal autophagy of cancer cells and resetting tumor-promoting M2 macrophages to the tumor-killing M1 phenotype.

Tubeimoside-1 induces TFEB-dependent lysosomal degradation of PD-L1 and promotes antitumor immunity by targeting mTOR

Programmed cell death ligand 1 (PD-L1)/programmed cell death protein 1 (PD-1) cascade is an effective therapeutic target for immune checkpoint blockade (ICB) therapy. Targeting PD-L1/PD-1 axis by small-molecule drug is an attractive approach to enhance antitumor immunity. Using flow cytometry-based assay, we identify tubeimoside-1 (TBM-1) as a promising antitumor immune modulator that negatively regulates PD-L1 level. TBM-1 disrupts PD-1/PD-L1 interaction and enhances the cytotoxicity of T cells toward cancer cells through decreasing the abundance of PD-L1. Furthermore, TBM-1 exerts its antitumor effect in mice bearing Lewis lung carcinoma (LLC) and B16 melanoma tumor xenograft via activating tumor-infiltrating T-cell immunity. Mechanistically, TBM-1 triggers PD-L1 lysosomal degradation in a TFEB-dependent, autophagy-independent pathway. TBM-1 selectively binds to the mammalian target of rapamycin (mTOR) kinase and suppresses the activation of mTORC1, leading to the nuclear translocation of TFEB and lysosome biogenesis. Moreover, the combination of TBM-1 and anti-CTLA-4 effectively enhances antitumor T-cell immunity and reduces immunosuppressive infiltration of myeloid-derived suppressor cells (MDSCs) and regulatory T (Treg) cells. Our findings reveal a previously unrecognized antitumor mechanism of TBM-1 and represent an alternative ICB therapeutic strategy to enhance the efficacy of cancer immunotherapy.

Autophagy in major human diseases

Autophagy is a core molecular pathway for the preservation of cellular and organismal homeostasis. Pharmacological and genetic interventions impairing autophagy responses promote or aggravate disease in a plethora of experimental models. Consistently, mutations in autophagy-related processes cause severe human pathologies. Here, we review and discuss preclinical data linking autophagy dysfunction to the pathogenesis of major human disorders including cancer as well as cardiovascular, neurodegenerative, metabolic, pulmonary, renal, infectious, musculoskeletal, and ocular disorders.

TCF4 enhances hepatic metastasis of colorectal cancer by regulating tumor-associated macrophage via CCL2/CCR2 signaling

Colorectal cancer (CRC) liver metastasis is a significant clinical problem for which better therapies are urgently needed. Tumor-associated macrophage, a major cell population in the tumor microenvironment, is a known contributor to primary cancer progression and cancer metastasis. Here, we found TAM recruitment and M2 polarization were increased in the hepatic metastatic lesion compared with the primary site of human CRC tissues. Moreover, Pearson correlation analysis showed that TAM recruitment and polarization were closely correlated with the elevated TCF4 expression in the metastatic site. To investigate the role of TCF4 in CRC liver metastasis, we generated a syngeneic mouse model using MC38 cells splenic injection. Results from in vivo experiments and mouse models revealed that TCF4 deficiency in MC38 cells does not affect their proliferation and invasion; however, it reduces TAM infiltration and M2 polarization in the metastasis site. Further studies indicated that these effects are mediated by the TCF4 regulated CCL2 and CCR2 expression. TCF4 or CCL2 silencing in the tumor cells prevent CRC liver metastasis in the mouse model. Altogether, these findings suggest that the TCF4-CCL2-CCR2 axis plays an essential role in CRC liver metastasis by enhancing TAMs recruitment and M2 polarization.

Hydroxychloroquine Attenuates Acute Inflammation (LPS)-Induced Apoptosis via Inhibiting TRPV1 Channel/ROS Signaling Pathways in Human Monocytes

Simple Summary

LPS is a well-known agent in cell line models, including U937 monocytes, for inducing acute inflammation (INF). It is not known whether antioxidant HCQ, through the inhibition of TRPV1 in U937, can decrease oxidative monocyte toxicity and cell death. We investigated the modulator action of HCQ treatment through the modulation of TRPV1 on the levels of mROS, INF, and apoptosis in an LPS-stimulated U937 monocyte model. Acute INF activates apoptotic, inflammatory, and oxidant action through acute INF-dependent excessive cROS, MDA, cytokine generation, and Ca²⁺ influx in U937 human monocyte cells. Furthermore, treatment with acute INF increases TRPV1 and apoptotic marker (CAS3, CAS9, Bax, and Bcl-2) concentrations via downregulation of glutathione level and glutathione peroxidase activity in U937 monocytes. The acute INF-caused U937 oxidative stress and cytotoxicity is diminished by the treatment of HCQ and TRPV1 inhibitor (CPZ). In summary, treatment with HCQ and CPZ induced anti-inflammatory, anti-apoptotic, and antioxidant action via the inhibition of cROS, cytokine generation, and caspase activation.

Abstract

Acute inflammation (INF) and apoptosis are induced in monocytes by the generation of several factors, including the products of cytosolic oxygen free radicals (cROS) and the excessive influx of Ca²⁺ via the stimulation of TRPV1. These are main factors in the etiology of monocyte activation-induced inflammatory and neurodegenerative diseases. Importantly, the protective action of hydroxychloroquine (HCQ) treatment via the inhibition of TRPV1 on the levels of inflammatory factors, cROS, and apoptosis in acute INF (lipopolysaccharide, LPS)-exposed neuronal cells was recently reported. However, the relationships between acute INF via TRPV1 activation and HCQ in monocytes have not been fully clarified yet. The cell membrane of U937 human monocytes contains natural TRPV1. In the study plan, we used U937 cells in four main groups, namely control, HCQ (60 μM for 48 h), INF (1 μg/mL LPS for 16 h), and HCQ + INF. The current data indicate that LPS-induced acute INF caused the upregulation of excessive cytosolic Ca²⁺ accumulation via the stimulation of TRPV1 in the cells. The treatment of INF additionally upregulated the levels of apoptosis and cytokines (IL6, IL1β, and TNFα), due to upregulated cROS and lipid peroxidation levels as well as upregulated generation of caspase -3 (CAS3) and -9 (CAS9) but a decrease in glutathione and glutathione peroxidase. The expression levels of TRPV1, Bax, CAS3, and CAS9 were also upregulated by the treatment of LPS. However, treatment with HCQ and TRPV1 blocker (capsazepine) modulated the levels of cytokines, caspases, cROS, Ca²⁺ influx, and apoptosis through the modulation of TRPV1 in the U937 that were stimulated with LPS. In summary, the present data suggest TRPV1 activation through the acute INF (LPS)-induced inflammatory, oxidant, and apoptotic adverse actions in monocyte cells, whereas HCQ prevented adverse actions via the modulation of TRPV1. The results may be significant in the modulation of monocyte activation-caused inflammatory and neurodegenerative diseases.

Recent progress of autophagy signaling in tumor microenvironment and its targeting for possible cancer therapeutics

Autophagy, a lysosomal catabolic process, involves degradation of cellular materials, protein aggregate, and dysfunctional organelles to maintain cellular homeostasis. Strikingly, autophagy exhibits a dual-sided role in cancer; on the one hand, it promotes clearance of transformed cells and inhibits tumorigenesis, while cytoprotective autophagy has a role in sustaining cancer. The autophagy signaling in the tumor microenvironment (TME) during cancer growth and therapy is not adequately understood. The review highlights the role of autophagy signaling pathways to support cancer growth and progression in adaptation to the oxidative and hypoxic context of TME. Furthermore, autophagy contributes to regulating the metabolic switch for generating sufficient levels of high-energy metabolites, including amino acids, ketones, glutamine, and free fatty acids for cancer cell survival. Interestingly, autophagy has a critical role in modulating the tumor-associated fibroblast resulting in different cytokines and paracrine signaling mediated angiogenesis and invasion of pre-metastatic niches to secondary tumor sites. Moreover, autophagy promotes immune evasion to inhibit antitumor immunity, and autophagy inhibitors enhance response to immunotherapy with infiltration of immune cells to the TME niche. Furthermore, autophagy in TME maintains and supports the survival of cancer stem cells resulting in chemoresistance and therapy recurrence. Presently, drug repurposing has enabled the use of lysosomal inhibitor-based antimalarial drugs like chloroquine and hydroxychloroquine as clinically available autophagy inhibitors in cancer therapy. We focus on the recent developments of multiple autophagy modulators from pre-clinical trials and the challenges in developing autophagy-based cancer therapy.

Matter of TIME: the tumor-immune microenvironment of mesothelioma and implications for checkpoint blockade efficacy

Malignant pleural mesothelioma (MPM) is an incurable cancer with a dismal prognosis and few effective treatment options. Nonetheless, recent positive phase III trial results for immune checkpoint blockade (ICB) in MPM herald a new dawn in the fight to advance effective treatments for this cancer. Tumor mutation burden (TMB) has been widely reported to predict ICB in other cancers, but MPM is considered a low-TMB tumor. Similarly, tumor programmed death-ligand 1 (PD-L1) expression has not been proven predictive in phase III clinical trials in MPM. Consequently, the precise mechanisms that determine response to immunotherapy in this cancer remain unknown. The present review therefore aimed to synthesize our current understanding of the tumor immune microenvironment in MPM and reflects on how specific cellular features might impact immunotherapy responses or lead to resistance. This approach will inform stratified approaches to therapy and advance immunotherapy combinations in MPM to improve clinical outcomes further.