Intravenous delivery of siRNA targeting CD47 effectively inhibits melanoma tumor growth and lung metastasis

Dual-Action Protein-siRNA Conjugates for Targeted Disruption of CD47-Signal Regulatory Protein α Axis in Cancer Therapy

A series of successes in RNA interference (RNAi) therapies for liver diseases using lipid nanoparticles and N-acetylgalactosamine have heralded a current era of RNA therapeutics. However, alternative delivery strategies are required to take RNAi out of the comfort zone of hepatocytes. Here we report SIRPα IgV/anti-CD47 siRNA (vS-siCD47) conjugates that selectively and persistently disrupt the antiphagocytic CD47/SIRPα axis in solid tumors. Conjugation of the SIRPα IgV domain protein to siRNAs enables tumor dash through CD47-mediated erythrocyte piggyback, primarily blocking the physical interaction between CD47 on cancer cells and SIRPα on phagocytes. After internalization of the vS-siCD47 conjugates within cancer cells, the detached free-standing anti-CD47 siRNAs subsequently attack CD47 through the RNAi mechanism. The dual-action approach of the vS-siCD47 conjugate effectively overcomes the "don't eat me" barrier and stimulates phagocyte-mediated tumor destruction, demonstrating a highly selective and potent CD47-blocking immunotherapy. This delivery strategy, employing IgV domain protein-siRNA conjugates with a dual mode of target suppression, holds promise for expanding RNAi applications beyond hepatocytes and advancing RNAi-based cancer immunotherapies for solid tumors.

A Gene-Editable Palladium-Based Bioorthogonal Nanoplatform Facilitates Macrophage Phagocytosis for Tumor Therapy

Macrophage phagocytosis of tumor cells has emerged as an attractive strategy for tumor therapy. Nevertheless, immunosuppressive M2 macrophages in the tumor microenvironment and the high expression of anti-phagocytic signals from tumor cells impede therapeutic efficacy. To address these issues and improve the management of malignant tumors, in this study we developed a gene-editable palladium-based bioorthogonal nanoplatform, consisting of CRISPR/Cas9 gene editing system-linked Pd nanoclusters, and a hyaluronic acid surface layer (HBPdC). This HBPdC nanoplatform exhibited satisfactory tumor-targeting efficiency and triggered Fenton-like reactions in the tumor microenvironment to generate reactive oxygen species for chemodynamic therapy and macrophage M1 polarization, which directly eliminated tumor cells, and stimulated the antitumor response of macrophages. HBPdC could reprogram tumor cells through gene editing to reduce the expression of CD47 and adipocyte plasma membrane-associated protein, thereby promoting their recognition and phagocytosis by macrophages. Moreover, HBPdC induced the activation of sequestered prodrugs via bioorthogonal catalysis, enabling chemotherapy and thereby enhancing tumor cell death. Importantly, the Pd nanoclusters of HBPdC were sufficiently cleared through basic metabolic pathways, confirming their biocompatibility and biosafety. Therefore, by promoting macrophage phagocytosis, the HBPdC system developed herein represents a highly promising antitumor toolset for cancer therapy applications.

CD47: The Next Frontier in Immune Checkpoint Blockade for Non-Small Cell Lung Cancer

The success of PD-1/PD-L1-targeted therapy in lung cancer has resulted in great enthusiasm for additional immunotherapies in development to elicit similar survival benefits, particularly in patients who do not respond to or are ineligible for PD-1 blockade. CD47 is an immunosuppressive molecule that binds SIRPα on antigen-presenting cells to regulate an innate immune checkpoint that blocks phagocytosis and subsequent activation of adaptive tumor immunity. In lung cancer, CD47 expression is associated with poor survival and tumors with EGFR mutations, which do not typically respond to PD-1 blockade. Given its prognostic relevance, its role in facilitating immune escape, and the number of agents currently in clinical development, CD47 blockade represents a promising next-generation immunotherapy for lung cancer. In this review, we briefly summarize how tumors disrupt the cancer immunity cycle to facilitate immune evasion and their exploitation of immune checkpoints like the CD47-SIRPα axis. We also discuss approved immune checkpoint inhibitors and strategies for targeting CD47 that are currently being investigated. Finally, we review the literature supporting CD47 as a promising immunotherapeutic target in lung cancer and offer our perspective on key obstacles that must be overcome to establish CD47 blockade as the next standard of care for lung cancer therapy.

Enhanced tumor immunotherapy by polyfunctional CD19-CAR T cells engineered to secrete anti-CD47 single-chain variable fragment

A high recurrence rate of non-Hodgkin's lymphoma (NHL) following chimeric antigen receptor T (CAR T) cell treatment remains a bottleneck, and immunosuppressive tumor microenvironment (TME) compromising CAR T cell efficacy in NHL is the primary cause of relapse. Accordingly, modifying the structure of CAR T cells to attenuate the inhibitory effect of TME thus reducing recurrence rate is a valuable research topic. CD47 has been proved to be a promising therapeutic target and is crucial in regulating macrophage function. Herein, we engineered CD19-CAR T cells to secrete an anti-CD47 single-chain variable fragment (scFv) and validated their function in enhancing antitumor efficacy, regulating T cells differentiation, modifying phagocytosis and polarization of macrophages by in vitro and in vivo researches. The efficacy was analogous or preferable to the combination of CAR T cells and CD47 antibody. Of note, anti-CD47 scFv secreting CAR T cells exert a more potent immune response following specific antigen stimulation compared with parental CAR T cells, characterized by more efficient degranulation and cytokine production with polyfunctionality. Furthermore, locally delivering anti-CD47 by CAR T cells potentially limits toxicities relevant to systemic antibody treatment. Collectively, our research provides a more effective and safer CAR T cell transformation method for enhancing tumor immunotherapy.

Tumor-associated macrophages in nanomaterial-based anti-tumor therapy: as target spots or delivery platforms

Targeting tumor-associated macrophages (TAMs) has emerged as a promising approach in cancer therapy. This article provides a comprehensive review of recent advancements in the field of nanomedicines targeting TAMs. According to the crucial role of TAMs in tumor progression, strategies to inhibit macrophage recruitment, suppress TAM survival, and transform TAM phenotypes are discussed as potential therapeutic avenues. To enhance the targeting capacity of nanomedicines, various approaches such as the use of ligands, immunoglobulins, and short peptides are explored. The utilization of live programmed macrophages, macrophage cell membrane-coated nanoparticles and macrophage-derived extracellular vesicles as drug delivery platforms is also highlighted, offering improved biocompatibility and prolonged circulation time. However, challenges remain in achieving precise targeting and controlled drug release. The heterogeneity of TAMs and the variability of surface markers pose hurdles in achieving specific recognition. Furthermore, the safety and clinical applicability of these nanomedicines requires further investigation. In conclusion, nanomedicines targeting TAMs hold great promise in cancer therapy, offering enhanced specificity and reduced side effects. Addressing the existing limitations and expanding our understanding of TAM biology will pave the way for the successful translation of these nano-therapies into clinical practice.

Comparison of immunotherapy mediated by apoptotic bodies, microvesicles and exosomes: apoptotic bodies' unique anti-inflammatory potential

Immunotherapy, including immunostimulation and immunosuppression, has seen significant development in the last 10 years. Immunostimulation has been verified as effective in anti-cancer treatment, while immunosuppression is used in the treatment of autoimmune disease and inflammation. Currently, with the update of newly-invented simplified isolation methods and the findings of potent triggered immune responses, extracellular vesicle-based immunotherapy is very eye-catching. However, the research on three main types of extracellular vesicles, exosomes, microvesicles and apoptotic bodies, needs to be more balanced. These three subtypes share a certain level of similarity, and at the same time, they have their own properties caused by the different methods of biogensis. Herein, we summarized respectively the status of immunotherapy based on each kind of vesicle and discuss the possible involved mechanisms. In conclusion, we highlighted that the effect of the apoptotic body is clear and strong. Apoptotic bodies have an excellent potential in immunosuppressive and anti-inflammatory therapies .

Targeting CD47 as a therapeutic strategy: A common bridge in the therapy of COVID-19-related cancers

Macrophages are essential mediators of innate immunity. Non-self-cells resist phagocytosis through the expression of the checkpoint molecule CD47. CD47, as the integrin-associated protein, is overexpressed on tumor and SARS-CoV-2-infected cells as a potential surface biomarker for immune surveillance evasion. CD47-signal-regulating protein alpha (SIRPα) interaction is a promising innate immunotarget. Previous findings based on monoclonal antibodies (mAbs) or fusion proteins that block CD47 or SIRPα have been developed in cancer research. While CD47 efficacy in infectious diseases, especially severe COVID-19 studies, is lacking, focus on macrophage-mediated immunotherapy that increases "eat me" signals in combination therapy with mAbs is optimistic. This integrin-related protein can be as a potential target to therapy for COVID-19. Here, we concentrate on the role of the CD47 signaling pathway as a novel therapeutic strategy for COVID-19-associated cancer treatment.

Emergence of Small Interfering RNA-Based Gene Drugs for Various Diseases

Small molecule, peptide, and protein-based drugs have been developed over decades to treat various diseases. The importance of gene therapy as an alternative to traditional drugs has increased after the discovery of gene-based drugs such as Gendicine for cancer and Neovasculgen for peripheral artery disease. Since then, the pharma sector is focusing on developing gene-based drugs for various diseases. After the discovery of the RNA interference (RNAi) mechanism, the development of siRNA-based gene therapy has been accelerated immensely. siRNA-based treatment for hereditary transthyretin-mediated amyloidosis (hATTR) using Onpattro and acute hepatic porphyria (AHP) by Givlaari and three more FDA-approved siRNA drugs has set up a milestone and further improved the confidence for the development of gene therapeutics for a spectrum of diseases. siRNA-based gene drugs have more advantages over other gene therapies and are under study to treat different types of diseases such as viral infections, cardiovascular diseases, cancer, and many more. However, there are a few bottlenecks to realizing the full potential of siRNA-based gene therapy. They include chemical instability, nontargeted biodistribution, undesirable innate immune responses, and off-target effects. This review provides a comprehensive view of siRNA-based gene drugs: challenges associated with siRNA delivery, their potential, and future prospects.

Lipid-based nanoparticles for cancer immunotherapy

As the fourth most important cancer management strategy except surgery, chemotherapy and radiotherapy, cancer immunotherapy has been confirmed to elicit durable antitumor effects in the clinic by leveraging the patient's own immune system to eradicate the cancer cells. However, the limited population of patients who benefit from the current immunotherapies and the immune related adverse events hinder its development. The immunosuppressive microenvironment is the main cause of the failure, which leads to cancer immune evasion and immunity cycle blockade. Encouragingly, nanotechnology has been engineered to enhance the efficacy and reduce off-target toxicity of their therapeutic cargos by spatiotemporally controlling the biodistribution and release kinetics. Among them, lipid-based nanoparticles are the first nanomedicines to make clinical translation, which are now established platforms for diverse areas. In this perspective, we discuss the available lipid-based nanoparticles in research and market here, then describe their application in cancer immunotherapy, with special emphasis on the T cells-activated and macrophages-targeted delivery system. Through perpetuating each step of cancer immunity cycle, lipid-based nanoparticles can reduce immunosuppression and promote drug delivery to trigger robust antitumor response.

Bionic lipoprotein loaded with chloroquine-mediated blocking immune escape improves antitumor immunotherapy

Tumor immunotherapy hold great promise for eradicating tumors. However, immune escape and the immunosuppressive microenvironment of tumor usually limit the efficiency of tumor immunotherapy. Therefore, simultaneously blocking immune escape and improving immunosuppressive microenvironment are the current problems to be solved urgently. Among them, CD47 on cancer cells membrane could bind to signal regulatory protein α (SIRPα) on macrophages membrane and sent out "don't eat me" signal, which was an important pathway of immune escape. The large number of M2-type macrophages in tumor microenvironment was a significant factor contributing to the immunosuppressive microenvironment. Here, we present a drug loading system for enhancing cancer immunotherapy, comprising CD47 antibody (aCD47) and chloroquine (CQ) with Bionic lipoprotein (BLP) carrier (BLP-CQ-aCD47). On the one hand, as drug delivery carrier, BLP could allow CQ to be preferentially taken up by M2-type macrophages, thereby efficiently polarized M2-type tumor-promoting cells into M1-type anti-tumor cells. On the other hand, blocking CD47 from binding to SIRPα could block the "don't eat me" signal, and improve the phagocytosis of macrophages to tumor cells. Taken together, BLP-CQ-aCD47 could block immune escape, improve immunosuppressive microenvironment of tumor, and induce a strong immune response without substantial systemic toxicity. Therefore, it provides a new idea for tumor immunotherapy.

Emerging phagocytosis checkpoints in cancer immunotherapy

Cancer immunotherapy, mainly including immune checkpoints-targeted therapy and the adoptive transfer of engineered immune cells, has revolutionized the oncology landscape as it utilizes patients' own immune systems in combating the cancer cells. Cancer cells escape immune surveillance by hijacking the corresponding inhibitory pathways via overexpressing checkpoint genes. Phagocytosis checkpoints, such as CD47, CD24, MHC-I, PD-L1, STC-1 and GD2, have emerged as essential checkpoints for cancer immunotherapy by functioning as "don't eat me" signals or interacting with "eat me" signals to suppress immune responses. Phagocytosis checkpoints link innate immunity and adaptive immunity in cancer immunotherapy. Genetic ablation of these phagocytosis checkpoints, as well as blockade of their signaling pathways, robustly augments phagocytosis and reduces tumor size. Among all phagocytosis checkpoints, CD47 is the most thoroughly studied and has emerged as a rising star among targets for cancer treatment. CD47-targeting antibodies and inhibitors have been investigated in various preclinical and clinical trials. However, anemia and thrombocytopenia appear to be formidable challenges since CD47 is ubiquitously expressed on erythrocytes. Here, we review the reported phagocytosis checkpoints by discussing their mechanisms and functions in cancer immunotherapy, highlight clinical progress in targeting these checkpoints and discuss challenges and potential solutions to smooth the way for combination immunotherapeutic strategies that involve both innate and adaptive immune responses.

MiR-133a/CD47 axis is a novel prognostic biomarker to promote triple negative breast cancer progression

Cluster of differentiation 47 (CD47) acts as an anti-engulfment signal on tumor cells, and its overexpression is correlated with poor prognosis of various malignant tumors. However, the role and mechanism of CD47 in tumor cell proliferation, migration and apoptosis remain unclarified. Emerging evidence indicates that microRNAs (miRNAs) are potential regulators to mediate CD47 generation. In this study, we found that CD47 was up-regulated while miR-133a was down-regulated in triple-negative breast cancer (TNBC) in vitro and in vivo. Moreover, we demonstrated for the first time that CD47 was a direct target of miR-133a in TNBC cells, and provided direct evidence of the inverse correlation between miR-133a and CD47 expression in TNBC. Besides, miR-133a functioned as a tumor suppressor to inhibit proliferation and migration, and promote apoptosis of TNBC cells by targeting CD47. Furthermore, overexpression of miR-133a inhibited the tumor growth of TNBC in an in vivo xenograft animal model by targeting CD47. Thus, miR-133a/CD47 axis provides new insight into the mechanism of TNBC progression and could be a promising candidate in the diagnosis and treatment of TNBC.

Self-Assembled Oleic Acid-Modified Polyallylamines for Improved siRNA Transfection Efficiency and Lower Cytotoxicity

Small interference RNA (siRNA) is a tool for gene modulation, which can silence any gene involved in genetic disorders. The potential of this therapeutic tool is hampered by RNA instability in the blood stream and difficulties to reach the cytosol. Polyamine-based nanoparticles play an important role in gene delivery. Polyallylamine hydrochloride (PAH) is a polycation displaying primary amines that can be easily chemically modified to match the balance between cell viability and siRNA transfection. In this work, PAH has been covalently functionalized with oleic acid at different molar ratios by carbodiimide chemistry. The substituted polymers form polyplexes that keep positive surface charge and fully encapsulate siRNA. Oleic acid substitution improves cell viability in the pulmonary cell line A549. Moreover, 6 and 14% of oleic acid substitution show an improvement in siRNA transfection efficiency. CD47 is a ubiquitous protein which acts as "don't eat me signal." SIRPα protein of macrophages recognizes CD47, leading to tumor cell phagocytosis by macrophages. By knocking down CD47 with siRNA, cancer cells become vulnerable to be eliminated by the immune system. PAH-oleic acid substitutes show high efficacy in silencing the CD47 protein, making them a potential candidate for immunotherapy.

Blood Clot Scaffold Loaded with Liposome Vaccine and siRNAs Targeting PD-L1 and TIM-3 for Effective DC Activation and Cancer Immunotherapy

Tumor vaccines have been showing a relatively weak response rate in cancer patients, while deficiencies in delivery efficiency to dendritic cells (DCs), as well as DC-intrinsic immunosuppressive signals, contribute to a great extent. In this work, we report an implantable blood clot loaded with liposomes-protamine-hyaluronic acid nanoparticles (LPH NPs) containing vaccine (LPH-vaccine) and LPH NPs containing siRNA (LPH-siRNA) for synergistic DC recruitment and activation. The subcutaneously implanted blood clot scaffold can recruit abundant immune cells, particularly DCs, to form a DC-rich environment in vivo. Within the scaffold, LPH-vaccine effectively delivers antigens and adjuvants to the recruited DCs and induces the maturation of DCs. More importantly, LPH-siRNA that targets programmed death-ligand 1 (PD-L1) and T cell immunoglobulin and mucin-containing molecule 3 (TIM-3) can reduce immunosuppressive signals in mature DCs and prevent the DCs from expressing a regulatory program in the scaffold. The activated DCs correlate with an improved magnitude and efficacy of T cell priming, resulting in the production of tumor antigen-specific T cells in multiple mouse models. Our strategy can also be used for patient-tailored therapy by change of tumor neoantigens, suggesting a promising strategy for cancer therapy in the clinic.

Prognostic Utility of CD47 in Cancer of the Uterine Cervix and the Sensitivity of Immunohistochemical Scores

INTRODUCTION

Cancer of the uterine cervix (CUC) is still one of the most frequent oncological diagnoses in women. The specific interactions between the tumor cells of CUC and the cells and tissues in the tumor microenvironment can affect cancer cells' invasive and metastatic potential and can modulate tumor's progression and death. CD47 is a trans-membranous immunoglobulin, expressed in many cells. It protects the cells from being destroyed by the circulating macrophages.

AIM

We aimed to evaluate the prognostic role of CD47 expressed in the tumor tissues of patients with CUC for tumor progression and to find the most sensitive immunohistochemical score for defining the cut-off significantly associated with tumor biology and progression.

MATERIALS AND METHODS

Paraffin-embedded tumor tissues from 86 patients with CUC were included in the study. Clinico-morphological data for patients, such as age and stage at diagnosis according to FIGO and TNM classification, were obtained from the hospital electronic medical records. Immunohistochemical staining was performed with rabbit recombinant monoclonal CD47 antibody (Clone SP279). The final result was interpreted based on three reporting models in immunohistochemistry: H-score, Allred score and combined score.

RESULTS

The expression of CD47 was higher in tumors limited in the cervix compared with those invading other structures, and it did not depend on the nodal status. The results of immunohistochemical staining were similar regardless of which immunohistochemical method was used. The most significant correlation with TNM stage was observed with the H-score (p = 0.00018). The association with the Allred and combined score was less significant, with p values of 0.0013 and 0.0002, respectively.

CONCLUSION

The expression of CD47 in the cancer cells is prognostic for tumor invasion in the surrounding structures, independent of lymph node engagement. The H-score is the most sensitive immunohistochemical score to describe tumor stage. To the best of our knowledge, this is the first study evaluating the significance of CD47 expression in CUC.

Targeting Menin and CD47 to Address Unmet Needs in Acute Myeloid Leukemia

After forty years of essentially unchanged treatment in acute myeloid leukemia (AML), innovation over the past five years has been rapid, with nine drug approvals from 2016 to 2021. Increased understanding of the molecular changes and genetic ontology of disease have led to targeting mutations in isocitrate dehydrogenase, FMS-like tyrosine kinase 3 (FLT3), B-cell lymphoma 2 and hedgehog pathways. Yet outcomes remain variable; especially in defined molecular and genetic subgroups such as NPM1 (Nucleophosmin 1) mutations, 11q23/KMT2A rearranged and TP53 mutations. Emerging therapies seek to address these unmet needs, and all three of these subgroups have promising new therapeutic approaches. Here, we will discuss the normal biological roles of menin in acute leukemia, notably in KMT2A translocations and NPM1 mutation, as well as current drug development. We will also explore how CD47 inhibition may move immunotherapy into front-line settings and unlock new treatment strategies in TP53 mutated disease. We will then consider how these new therapeutic advances may change the management of AML overall.

Role of exosomal non-coding RNAs from tumor cells and tumor-associated macrophages in the tumor microenvironment

Exosomes have a crucial role in intercellular communication and mediate interactions between tumor cells and tumor-associated macrophages (TAMs). Exosome-encapsulated non-coding RNAs (ncRNAs) are involved in various physiological processes. Tumor-derived exosomal ncRNAs induce M2 macrophage polarization through signaling pathway activation, signal transduction, and transcriptional and post-transcriptional regulation. Conversely, TAM-derived exosomal ncRNAs promote tumor proliferation, metastasis, angiogenesis, chemoresistance, and immunosuppression. MicroRNAs induce gene silencing by directly targeting mRNAs, whereas lncRNAs and circRNAs act as miRNA sponges to indirectly regulate protein expressions. The role of ncRNAs in tumor-host interactions is ubiquitous. Current research is increasingly focused on the tumor microenvironment. On the basis of the "cancer-immunity cycle" hypothesis, we discuss the effects of exosomal ncRNAs on immune cells to induce T cell exhaustion, overexpression of programmed cell death ligands, and create a tumor immunosuppressive microenvironment. Furthermore, we discuss potential applications and prospects of exosomal ncRNAs as clinical biomarkers and drug delivery systems.

CD47 Expression in Non-Melanoma Skin Cancers and Its Clinicopathological Implications

CD47 is a cell surface molecule and regulates diverse cellular responses. CD47 is highly expressed in cancer cells and has potential as a therapeutic target and prognostic factor in cancer patients. The expression patterns of CD47 in basal cell carcinoma (BCC), squamous cell carcinoma (SCC) and its precursor lesions, and its clinicopathological significance were investigated. CD47 expression was evaluated by immunohistochemistry in 152 cases of BCC and 71 cases of SCC. For comparison of CD47 expression, actinic keratosis (AK), squamous cell carcinoma in situ (SCCIS), keratoacanthoma (KA), and normal skin (NS) tissue were used. CD47 expression in BCC was significantly lower than that of SCC (p < 0.001). CD47 expression levels in SCC and KA were significantly higher than those of NS and AK (p < 0.05). High CD47 expression was significantly associated with the presence of ulceration (p = 0.005) and a deeper level of invasion (p = 0.011) in BCC. In addition, high CD47 expression was significantly associated with the presence of ulceration (p = 0.019) and larger tumor size (p = 0.004) in SCC. CD47 expression was associated with tumorigenesis and tumor progression in non-melanoma skin cancers.

Knockdown of LMNB1 Inhibits the Proliferation of Lung Adenocarcinoma Cells by Inducing DNA Damage and Cell Senescence

Background

Lung cancer has considerably high mortality and morbidity rate. Lung adenocarcinoma (LUAD) tissues highly express lamin B1 (LMNB1), compared with normal tissues. In this study, we knocked down LMNB1 in LUAD cells A549 and NCI-1299 to explore the effect of its inhibition on the proliferation of cells and the potential mechanism.

Methods

Using bioinformatics methods, we analyzed the specificity of LMNB1 mRNA expression level in LUAD and its effect on prognosis from TCGA data. SiRNAs were used to knock down LMNB1 in the A549 cell line, and the knockdown effect was identified by western blotting and qRT-PCR. Through CCK8 cell proliferation assay, wound healing assay, TRAP, cloning formation Assay, DNase I-TUNEL assay, ATAC-seq, immunofluorescence, FISH, in vivo mouse xenograft studies, etc, we evaluated the influence and mechanism of LMNB1 on LUAD cell line proliferation in vitro and in vivo.

Results

According to bioinformatics analysis, LMNB1 is substantially abundant in LUAD tissues and is associated with tumor stage and patient survival (P < 0.05). After silencing LMNB1, the rate of cell growth, wound healing, the number of transwells, and the number of cell colonies all decreased significantly (P < 0.01). With the decreased LMNB1 expression, H3K9me3 protein expression decreases, chromosome accessibility increases, P53, P21, P16 and γ-H2AX protein expression increases, and the number of senescence staining positive cells increases. At the same time, in vivo mouse xenograft experiments showed that the tumor volume of the LMNB1-silenced group was significantly reduced, compared to that of the control group (P < 0.01), and the proliferation biomarker Ki-67 level (P < 0.01) was considerably reduced.

Conclusions

Overexpression of LMNB1 in LUAD cells is significant, which has excellent potential to be an indicator for evaluating the clinical prognosis of LUAD patients and a target for precise treatment.

Human lung adenocarcinoma CD47 is upregulated by interferon-γ and promotes tumor metastasis

Tumor cells can evade attack by phagocytes by upregulating the self-marker CD47. The mechanisms underlying tumor CD47 upregulation, however, remain unclear. Here, we report that human lung adenocarcinoma CD47 is upregulated by interferon-γ (IFN-γ), the level in the tumor microenvironment of which is markedly increased after tumor metastasis and chemotherapy. The IFN-γ receptor is expressed in various human lung adenocarcinoma tissues regardless of the CD47 protein expression, and lung adenocarcinoma CD47 expression is significantly enhanced following tumor metastasis or chemotherapy treatment. In line with this, CD47 expression in various lung cancer cells is markedly increased by IFN-γ treatment. Mechanistically, IFN-γ promotes CD47 expression by activating interferon regulatory factor-1 (IRF-1), which binds to an IRF-1-binding domain within the CD47 promoter region and increases CD47 transcription. Functionally, IFN-γ-enhanced CD47 expression facilitates human lung cancer cell invasion both in vitro and in vivo, whereas IFN-γ-induced CD47 upregulation and cancer metastasis are blocked by mutating the IRF-1-binding site within the CD47 promoter. Our results reveal IFN-γ-enhanced CD47 expression as a novel mechanism promoting human lung adenocarcinoma progression.

Tracing New Landscapes in the Arena of Nanoparticle-Based Cancer Immunotherapy

Over the past two decades, unique and comprehensive cancer treatment has ushered new hope in the holistic management of the disease. Cancer immunotherapy, which harnesses the immune system of the patient to attack the cancer cells in a targeted manner, scores over others by being less debilitating compared to the existing treatment strategies. Significant advancements in the knowledge of immune surveillance in the last few decades have led to the development of several types of immune therapy like monoclonal antibodies, cancer vaccines, immune checkpoint inhibitors, T-cell transfer therapy or adoptive cell therapy (ACT) and immune system modulators. Intensive research has established cancer immunotherapy to be a safe and effective method for improving survival and the quality of a patient’s life. However, numerous issues with respect to site-specific delivery, resistance to immunotherapy, and escape of cancer cells from immune responses, need to be addressed for expanding and utilizing this therapy as a regular mode in the clinical treatment. Development in the field of nanotechnology has augmented the therapeutic efficiency of treatment modalities of immunotherapy. Nanocarriers could be used as vehicles because of their advantages such as increased surface areas, targeted delivery, controlled surface and release chemistry, enhanced permeation and retention effect, etc. They could enhance the function of immune cells by incorporating immunomodulatory agents that influence the tumor microenvironment, thus enabling antitumor immunity. Robust validation of the combined effect of nanotechnology and immunotherapy techniques in the clinics has paved the way for a better treatment option for cancer than the already existing procedures such as chemotherapy and radiotherapy. In this review, we discuss the current applications of nanoparticles in the development of ‘smart’ cancer immunotherapeutic agents like ACT, cancer vaccines, monoclonal antibodies, their site-specific delivery, and modulation of other endogenous immune cells. We also highlight the immense possibilities of using nanotechnology to accomplish leveraging the coordinated and adaptive immune system of a patient to tackle the complexity of treating unique disease conditions and provide future prospects in the field of cancer immunotherapy.

Development of Novel CD47-Specific ADCs Possessing High Potency Against Non-Small Cell Lung Cancer in vitro and in vivo

Targeted therapies hold promise for efficiently and accurately delivering cytotoxic drugs directly to tumor tissue to exert anticancer effects. CD47 is a membrane protein expressed in a variety of malignant tumors and hematopoietic cells, which plays a key role in immune escape and tumor progression. Although CD47 immunocheckpoint therapy has been developed in recent years, many patients cannot benefit from it because of its low efficiency. To strengthen and extend the therapeutic efficacy of anti-CD47 monoclonal antibody (mAb), we used the newly developed 7DC2 and 7DC4 mAbs as the targeting payload adaptor and VCMMAE as the toxin payload to construct novel CD47-specific immunotoxin (7DC-VCMMAE) by engineering cysteine residues. These CD47-specific ADCs have the better cell penetration, excellent DAR, similar payload distribution and good antigen-binding affinity. In vitro, 7DC-VCMMAE treatment induced death of non-small cell lung cancer (NSCLC) cell lines 95D and SPC-A1, but not A549 that express low levels of CD47 on the cell membrane. This finding suggests that 7DC-VCMMAE may possess greater therapeutic effect on NSCLC tumors expressing a high level of CD47 antigen; however, 7DC-VCMMAE treatment also promoted phagocytosis of A549 cells by macrophages. In vivo, 7DC-VCMMAE treatment had remarkable antitumor effects in a NSCLC cell line-derived xenograft (CDX) mouse model based on nonobese diabetic/severe combined immunodeficient (NOD/SCID). In summary, this study combined VCMMAE with anti-CD47 mAbs, emphasizing a novel and promising immunotherapy method for direct killing of NSCLC, which provides a valuable new way to meet the needs of the cancer therapy field.

Overcoming Immunotherapeutic Resistance in PDAC: SIRPα-CD47 blockade

A daily increase in the number of new cases of pancreatic ductal adenocarcinoma remains an issue of contention in cancer research. The data revealed that a global cumulated case of about 500, 000 have been reported. This has made PDAC the fourteenth most occurring tumor case in cancer research. Furthermore, PDAC is responsible for about 466,003 deaths annually, representing the seventh prevalent type of cancer mortality. PDAC has no salient symptoms in its early stages. This has exasperated several attempts to produce a perfect therapeutic agent against PDAC. Recently, immunotherapeutic research has shifted focus to the blockade of checkpoint proteins in the management and of some cancers. Investigations have centrally focused on developing therapeutic agents that could at least to a significant extent block the SIRPα-CD47 signaling cascade (a cascade which prevent phagocytosis of tumors by dendritic cells, via the deactivation of innate immunity and subsequently resulting in tumor regression) with minimal side effects. The concept on the blockade of this interaction as a possible mechanism for inhibiting the progression of PDAC is currently being debated. This review examined the structure--function activity of SIRPα-CD47 interaction while discussing in detail the mechanism of tumor resistance in PDAC. Further, this review details how the blockade of SIRPα-CD47 interaction serve as a therapeutic option in the management of PDAC.

Recent Advances of Tumor Therapy Based on the CD47-SIRPα Axis

Cancer is still a major disease that is currently difficult for humans to overcome. When the expression of the cluster of differentiation 47 (CD47) is upregulated, tumor cells interact with the macrophage inhibitory receptor signal regulatory protein α (SIRPα) to transmit the "Don't eat me" signal, thereby avoiding phagocytosis by the macrophages. Therefore, when the CD47-SIRPα axis is inhibited, the macrophages' phagocytic function can be restored and can also exert antitumor effects. This Review mainly introduces recent advances in tumor therapy targeted on the CD47-SIRPα axis, including the antibody and fusion protein, small molecule, gene therapy, cell therapy, and drug delivery system, to inhibit the function of CD47 expressed on tumor cells and promote tumor phagocytosis by macrophages. In addition, this Review also summarizes the current approaches to avoid anemia, a common side effect of CD47-SIRPα inhibitions, and provides ideas for clinical transformation.

RNA-mediated immunotherapy regulating tumor immune microenvironment: next wave of cancer therapeutics

Accumulating research suggests that the tumor immune microenvironment (TIME) plays an essential role in regulation of tumor growth and metastasis. The cellular and molecular nature of the TIME influences cancer progression and metastasis by altering the ratio of immune- suppressive versus cytotoxic responses in the vicinity of the tumor. Targeting or activating the TIME components show a promising therapeutic avenue to combat cancer. The success of immunotherapy is both astounding and unsatisfactory in the clinic. Advancements in RNA-based technology have improved understanding of the complexity and diversity of the TIME and its effects on therapy. TIME-related RNA or RNA regulators could be promising targets for anticancer immunotherapy. In this review, we discuss the available RNA-based cancer immunotherapies targeting the TIME. More importantly, we summarize the potential of various RNA-based therapeutics clinically available for cancer treatment. RNA-dependent targeting of the TIME, as monotherapy or combined with other evolving therapeutics, might be beneficial for cancer patients’ treatment in the near future.

The Landscape of Nanovectors for Modulation in Cancer Immunotherapy

Immunotherapy represents a promising strategy for the treatment of cancer, which functions via the reprogramming and activation of antitumor immunity. However, adverse events resulting from immunotherapy that are related to the low specificity of tumor cell-targeting represent a limitation of immunotherapy's efficacy. The potential of nanotechnologies is represented by the possibilities of immunotherapeutical agents being carried by nanoparticles with various material types, shapes, sizes, coated ligands, associated loading methods, hydrophilicities, elasticities, and biocompatibilities. In this review, the principal types of nanovectors (nanopharmaceutics and bioinspired nanoparticles) are summarized along with the shortcomings in nanoparticle delivery and the main factors that modulate efficacy (the EPR effect, protein coronas, and microbiota). The mechanisms by which nanovectors can target cancer cells, the tumor immune microenvironment (TIME), and the peripheral immune system are also presented. A possible mathematical model for the cellular communication mechanisms related to exosomes as nanocarriers is proposed.

Strategies to deliver RNA by nanoparticles for therapeutic potential

The use of a variety of RNA molecules, including messenger RNA, small interfering RNA, and microRNA, has shown great potential for prevention and therapy of many pathologies. However, this therapeutic promise has historically been limited by short in vivo half-life, lack of targeted delivery, and safety issues. Nanoparticle (NP)-mediated delivery has been a successful platform to overcome these limitations, with multiple formulations already in clinical trials and approved by the FDA. Although there is a diversity of NPs in terms of material formulation, size, shape, and charge that have been proposed for biomedical applications, specific modifications are required to facilitate sufficient RNA delivery and adequate therapeutic effect. This includes optimization of (i) RNA incorporation into NPs, (ii) specific cell targeting, (iii) cellular uptake and (iv) endosomal escape ability. In this review, we summarize the methods by which NPs can be modified for RNA delivery to achieve optimal therapeutic effects.

Targeting macrophage-mediated tumor cell phagocytosis: An overview of phagocytosis checkpoints blockade, nanomedicine intervention, and engineered CAR-macrophage therapy

Immunotherapy has been developing at an unprecedented speed with promising therapeutic outcomes in the wide spectrum of cancers. Up until now, most immunotherapies have focused on adaptive immunity; however, investigating the potential of macrophage phagocytosis and consequent adaptive immune cross-priming has led to a growing interest in exploiting macrophages in cancer therapy. In light of the positive evidence from preclinical studies and early clinical data, targeting macrophage phagocytosis has become a promising therapeutic strategy. Here, we review therapies based on harnessing and amplifying macrophage phagocytosis, such as blocking phagocytosis checkpoints and exploiting nanoparticles as efficient approaches in elevating macrophages-mediated phagocytosis. The present study introduces CAR-macrophage as the state-of-the-art modality serving as the bridge between the innate and adaptive immune system to mount a superior anti-tumor response in the treatment of cancer. We also take a look at the recent reports of therapies based on CAR-engineered macrophages with the hope of providing a future research direction for expanding the application of CAR-macrophage therapy.

Imaging of Glioblastoma Tumor-Associated Myeloid Cells Using Nanobodies Targeting Signal Regulatory Protein Alpha

Glioblastoma (GBM) is the most common malignant primary brain tumor. Glioblastomas contain a large non-cancerous stromal compartment including various populations of tumor-associated macrophages and other myeloid cells, of which the presence was documented to correlate with malignancy and reduced survival. Via single-cell RNA sequencing of human GBM samples, only very low expression of PD-1, PD-L1 or PD-L2 could be detected, whereas the tumor micro-environment featured a marked expression of signal regulatory protein alpha (SIRPα), an inhibitory receptor present on myeloid cells, as well as its widely distributed counter-receptor CD47. CITE-Seq revealed that both SIRPα RNA and protein are prominently expressed on various populations of myeloid cells in GBM tumors, including both microglia- and monocyte-derived tumor-associated macrophages (TAMs). Similar findings were obtained in the mouse orthotopic GL261 GBM model, indicating that SIRPα is a potential target on GBM TAMs in mouse and human. A set of nanobodies, single-domain antibody fragments derived from camelid heavy chain-only antibodies, was generated against recombinant SIRPα and characterized in terms of affinity for the recombinant antigen and binding specificity on cells. Three selected nanobodies binding to mouse SIRPα were radiolabeled with ^99mTc, injected in GL261 tumor-bearing mice and their biodistribution was evaluated using SPECT/CT imaging and radioactivity detection in dissected organs. Among these, Nb15 showed clear accumulation in peripheral organs such as spleen and liver, as well as a clear tumor uptake in comparison to a control non-targeting nanobody. A bivalent construct of Nb15 exhibited an increased accumulation in highly vascularized organs that express the target, such as spleen and liver, as compared to the monovalent format. However, penetration into the GL261 brain tumor fell back to levels detected with a non-targeting control nanobody. These results highlight the tumor penetration advantages of the small monovalent nanobody format and provide a qualitative proof-of-concept for using SIRPα-targeting nanobodies to noninvasively image myeloid cells in intracranial GBM tumors with high signal-to-noise ratios, even without blood-brain barrier permeabilization.

Nanotechnology-based products for cancer immunotherapy

Abstract

Currently, nanoscale materials and scaffolds carrying antitumor agents to the tumor target site are practical approaches for cancer treatment. Immunotherapy is a modern approach to cancer treatment in which the body’s immune system adjusts to deal with cancer cells. Immuno-engineering is a new branch of regenerative medicine-based therapies that uses engineering principles by using biological tools to stimulate the immune system. Therefore, this branch’s final aim is to regulate distribution, release, and simultaneous placement of several immune factors at the tumor site, so then upgrade the current treatment methods and subsequently improve the immune system’s handling. In this paper, recent research and prospects of nanotechnology-based cancer immunotherapy have been presented and discussed. Furthermore, different encouraging nanotechnology-based plans for targeting various innate and adaptive immune systems will also be discussed. Due to novel views in nanotechnology strategies, this field can address some biological obstacles, although studies are ongoing.

Graphic abstract

Modulating expression of inhibitory and stimulatory immune 'checkpoints' using nanoparticulate-assisted nucleic acid delivery

Immune checkpoints are regulatory molecules responsible for determining the magnitude and nature of the immune response. The aim of immune checkpoint targeting immunotherapy is to manipulate these interactions, engaging the immune system in treatment of cancer. Clinically, the use of monoclonal antibodies to block immunosuppressive interactions has proven itself to be a highly effective immunotherapeutic intervention. Within the literature there are numerous candidates for next generation of immune checkpoint targeting strategies. One such example is the use of nucleic acid to alter expression levels of immune checkpoint molecules, either as antisense oligo nucleotides/siRNA, to downregulate inhibitory molecules, or mRNA/DNA, to express co-stimulatory molecules. A significant component of nucleic acid delivery is its formulation within a nanoparticulate system. In this review we discuss the progress of the preclinical application of nucleic acid-based immunotherapies to target a selection of co-inhibitory/co-stimulatory molecules. Furthermore, we identify the potential and current gaps within the literature which may form the basis of future work.

Phagocytic function of tumor-associated macrophages as a key determinant of tumor progression control: a review

Tumor-associated macrophage (TAM) phagocytic activity is emerging as a new mechanism to harness for cancer treatment. Currently, many approaches are investigated at the preclinical level and some modalities have now reached clinical trials, including the targeting of the phagocytosis inhibitor CD47. The rationale for increasing TAM phagocytic activity is to improve innate anticancer immunity, and to promote T-cell mediated adaptive immune responses. In this context, a clear understanding of the impact of TAM phagocytosis on both innate and adaptive immunity is critical. Indeed, uncertainties persist regarding the capacity of TAM to present tumor antigens to CD8 T cells by cross-presentation. This process is critical for an optimal cytotoxic T-cell immune response and can be mediated by dendritic cells but also potentially by macrophages. In addition, the engulfment of cancer cells affects TAM functionality, as apoptotic cell uptake (a process termed efferocytosis) promotes macrophage anti-inflammatory functions. Because of the abundance of TAM in most solid tumors and the common use of apoptosis inducers such as radiotherapy to treat patients with cancer, efferocytosis potentially affects the overall immune balance within the tumor microenvironment (TME). In this review, we will discuss how cancer cell phagocytosis by TAM impacts antitumor immunity. First, we will focus on the potential of the phagocytic activity of TAM per se to control tumor progression. Second, we will examine the potential of TAM to act as antigen presenting cells for tumor specific CD8 T cells, considering the different characteristics of this process in the tumor tissue and at the molecular level. Finally, we will see how phagocytosis and efferocytosis affect TAM functionality and how these mechanisms impact on antitumor immunity. A better understanding of these aspects will enable us to better predict and interpret the consequences of cancer therapies on the immune status of the TME. Future cancer treatment regimens can thereby be designed to not only impact directly on cancer cells, but also to favorably modulate TAM phagocytic activity to benefit from the potential of this central immune player to achieve more potent therapeutic efficacy.

7S,15R-Dihydroxy-16S,17S-Epoxy-Docosapentaenoic Acid, a Novel DHA Epoxy Derivative, Inhibits Colorectal Cancer Stemness through Repolarization of Tumor-Associated Macrophage Functions and the ROS/STAT3 Signaling Pathway

Colorectal cancer is a highly malignant cancer that is inherently resistant to many chemotherapeutic drugs owing to the complicated tumor-supportive microenvironment (TME). Tumor-associated macrophages (TAM) are known to mediate colorectal cancer metastasis and relapse and are therefore a promising therapeutic target. In the current study, we first confirmed the anti-inflammatory effect of 7S,15R-dihydroxy-16S,17S-epoxy-docosapentaenoic acid (diHEP-DPA), a novel DHA dihydroxy derivative synthesized in our previous work. We found that diHEP-DPA significantly reduced lipopolysaccharide (LPS)-induced inflammatory cytokines secretion of THP1 macrophages, IL-6, and TNF-α. As expected, diHEP-DPA also modulated TAM polarization, as evidenced by decreased gene and protein expression of the TAM markers, CD206, CD163, VEGF, and TGF-β1. During the polarization process, diHEP-DPA treatment decreased the concentration of TGF-β1, IL-1β, IL-6, and TNF-α in culture supernatants via inhibiting the NF-κB pathway. Moreover, diHEP-DPA blocked immunosuppression by reducing the expression of SIRPα in TAMs and CD47 in colorectal cancer cells. Knowing that an inflammatory TME largely serves to support epithelial-mesenchymal transition (EMT) and cancer stemness, we tested whether diHEP-DPA acted through polarization of TAMs to regulate these processes. The intraperitoneally injected diHEP-DPA inhibited tumor growth when administered alone or in combination with 5-fluorouracil (5-FU) chemotherapy in vivo. We further found that diHEP-DPA effectively reversed TAM-conditioned medium (TCCM)-induced EMT and enhanced colorectal cancer stemness, as evidenced by its inhibition of colorectal cancer cell migration, invasion and expression of EMT markers, as well as cancer cell tumorspheres formation, without damaging colorectal cancer cells. DiHEP-DPA reduced the population of aldehyde dehydrogenase (ALDH)-positive cells and expression of colorectal stemness marker proteins (CD133, CD44, and Sox2) by modulating TAM polarization. Additionally, diHEP-DPA directly inhibited cancer stemness by inducing the production of reactive oxygen species (ROS), which, in turn, reduced the phosphorylation of nuclear signal transducer and activator of transcription 3 (STAT3). These data collectively suggest that diHEP-DPA has the potential for development as an anticancer agent against colorectal cancer.

Preparation and evaluation of dabrafenib-loaded, CD47-conjugated human serum albumin-based nanoconstructs for chemoimmunomodulation

The transmembrane proteins, CD47 and signal-regulatory protein α are overexpressed in cancer cells and macrophages, respectively, and facilitate the escape of cancer cells from macrophage-mediated phagocytosis. The immunomodulatory and targeting properties of CD47, the chemotherapeutic effects of dabrafenib (D), and the anti-programmed death-1 antibodies (PD-1) pave the way for effective chemoimmunomodulation-mediated anticancer combination therapy. In this study, CD47-conjugated, D-loaded human serum albumin (HSA) nanosystems were fabricated by modified nanoparticle albumin-bound technology. Cis-aconityl-PEG-maleimide (CA), an acid-labile linker, was used to conjugate D@HSA and CD47; the resultant CD47-CA@D@HSA exhibited tumor-specificity through receptor targeting, as well as preferential cleavage and drug release in the acidic tumor microenvironment (pH 5) compared to normal physiological pH conditions (pH 6.5, 7.4). The successful preparation of nanosized (∼220 nm), narrowly dispersed (∼0.13) CD47-CA@D@HSA was proven by physicochemical characterization. In vitro and in vivo internalization, accumulation, cytotoxicity, and apoptosis were observed to be higher with CD47-conjugated nanoconstructs, than with free D or non-targeted nanoconstructs. CD47-CA@D@HSA was found to promote the infiltration of cytotoxic T cells and tumor-associated macrophages into tumors and improve in vivo tumor inhibition. Administration in combination with PD-1 further improved antitumor efficacy by promoting immune responses that blocked the immune checkpoint. No signs of toxicity were seen in mice treated with the nanoconstructs; the formulation was, therefore, thought to be biocompatible and as having potential for clinical use. The targeted chemoimmunomodulation achieved by this combination therapy was found to combat major immunosuppressive facets, making it a viable candidate for use in the treatment of cancer.

Nanomedicine-based cancer immunotherapy: recent trends and future perspectives

The combination of cancer immunotherapy with efficient functionalized nanosystems has emerged as a beneficial treatment strategy and its use has increased rapidly. The roles of stimuli-responsive nanosystems and nanomedicine-based cancer immunotherapy, a subsidiary discipline in the field of immunology, are pivotal. The present era is witnessing rapid advancements in the use of nanomedicine as a platform for investigating novel therapeutic applications and modern intelligent healthcare management strategies. The development of cancer nanomedicine has posthaste ratified the outcomes of immunotherapy to the subsequent stage in the current era of medical research. This review focuses on key findings with respect to the effectiveness of nanomedicine-based cancer immunotherapies and their applications, which include i) immune checkpoint inhibitors and nanomedicine, ii) CRISPR-Cas nanoparticles (NPs) in cancer immunotherapy, iii) combination cancer immunotherapy with core-shell nanoparticles, iv) biomimetic NPs for cancer immunotherapy, and v) CAR-T cells and cancer nanoimmunotherapy. By evaluating the state-of-the-art tools and taking the challenges involved into consideration, various aspects of the proposed nano-enabled therapeutic approaches have been discussed in this review.

Computational Approaches for Cancer-Fighting: From Gene Expression to Functional Foods

It is today widely accepted that a healthy diet is very useful to prevent the risk for cancer or its deleterious effects. Nutrigenomics studies are therefore taking place with the aim to test the effects of nutrients at molecular level and contribute to the search for anti-cancer treatments. These efforts are expanding the precious source of information necessary for the selection of natural compounds useful for the design of novel drugs or functional foods. Here we present a computational study to select new candidate compounds that could play a role in cancer prevention and care. Starting from a dataset of genes that are co-expressed in programmed cell death experiments, we investigated on nutrigenomics treatments inducing apoptosis, and searched for compounds that determine the same expression pattern. Subsequently, we selected cancer types where the genes showed an opposite expression pattern and we confirmed that the apoptotic/nutrigenomics expression trend had a significant positive survival in cancer-affected patients. Furthermore, we considered the functional interactors of the genes as defined by public protein-protein interaction data, and inferred on their involvement in cancers and/or in programmed cell death. We identified 7 genes and, from available nutrigenomics experiments, 6 compounds effective on their expression. These 6 compounds were exploited to identify, by ligand-based virtual screening, additional molecules with similar structure. We checked for ADME criteria and selected 23 natural compounds representing suitable candidates for further testing their efficacy in apoptosis induction. Due to their presence in natural resources, novel drugs and/or the design of functional foods are conceivable from the presented results.

An "eat me" combinatory nano-formulation for systemic immunotherapy of solid tumors

Rational: Tumor immunogenic cell death (ICD), induced by certain chemotherapeutic drugs such as doxorubicin (Dox), is a form of apoptosis potentiating a protective immune response. One of the hallmarks of ICD is the translocation of calreticulin to the cell surface acting as an 'eat me' signal. This manuscript describes the development of a stable nucleic acid-lipid particles (SNALPs) formulation for the simultaneous delivery of ICD inducing drug (Dox) with small interfering RNA (siRNA) knocking down CD47 (siCD47), the dominant 'don't eat me' marker, for synergistic enhancement of ICD. Methods: SNALPs loaded with Dox or siCD47 either mono or combinatory platforms were prepared by ethanol injection method. The proposed systems were characterized for particle size, surface charge, entrapment efficiency and in vitro drug release. The ability of the SNALPs to preserve the siRNA integrity in presence of serum and RNAse were assessed over 48 h. The in vitro cellular uptake and gene silencing of the prepared SNALPs was assessed in CT26 cells. The immunological responses of the SNALPs were defined in vitro in terms of surface calreticulin expression and macrophage-mediated phagocytosis induction. In vivo therapeutic studies were performed in CT26 bearing mice where the therapeutic outcomes were expressed as tumor volume, expression of CD4 and CD8 as well as in vivo silencing. Results: The optimized SNALPs had a particle size 122 ±6 nm and an entrapment efficiency > 65% for both siRNA and Dox with improved serum stability. SNALPs were able to improve siRNA and Dox uptake in CT26 cells with enhanced cytotoxicity. siCD47 SNALPs were able to knockdown CD47 by approximately 70% with no interference from the presence of Dox. The siCD47 and Dox combination SNALPs were able to induce surface calreticulin expression leading to a synergistic effect on macrophage-mediated phagocytosis of treated cells. In a tumor challenge model, 50% of mice receiving siCD47 and Dox containing SNALPs were able to clear the tumor, while the remaining animals showed significantly lower tumor burden as compared to either monotreatment. Conclusion: Therefore, the combination of siCD47 and Dox in a particulate system showed potent anti-tumor activity which merits further investigation in future clinical studies.

The regulation of CD47-SIRPα signaling axis by microRNAs in combination with conventional cytotoxic drugs together with the help of nano-delivery: a choice for therapy?

CD47, a member of the immunoglobulin superfamily, is an important "Don't Eat-Me" signal in phagocytosis process [clearance of apoptotic cells] as well as a regulator of the adaptive immune response. The lower level of CD47 on the cell surface leads to the clearance of apoptotic cells. Dysregulation of CD47 plays a critical role in the development of disorders, particularly cancers. In cancers, recognition of CD47 overexpression on the surface of cancer cells by its receptor, SIRPα on the phagocytic cells, inhibits phagocytosis of cancer cells. Thus, blocking of CD47-SIRPα signaling axis might be as a promising therapeutic target, which promotes phagocytosis of cancer cells, antigen-presenting cell function as well as adaptive T cell-mediated anti-cancer immunity. In this respect, it has been reported that CD47 expression can be regulated by microRNAs (miRNAs). MiRNAs can regulate phagocytosis of macrophages apoptotic process, drug resistance, relapse of disease, radio-sensitivity, and suppress cell proliferation, migration, and invasion through post-transcriptional regulation of CD47-SIRPα signaling axis. Moreover, the regulation of CD47 expression by miRNAs and combination with conventional cytotoxic drugs together with the help of nano-delivery represent a valuable opportunity for effective cancer treatment. In this review, we review studies that evaluate the role of miRNAs in the regulation of CD47-SIRPα in disorders to achieve a novel preventive, diagnostic, and therapeutic strategy.Please confirm if the author names are presented accurately and in the correct sequence (given name, middle name/initial, family name). Also, kindly confirm the details in the metadata are correct. Confirmed.Journal standard instruction requires a structured abstract; however, none was provided. Please supply an Abstract with subsections..Not confirmed. This is a review article. According to submission guidelines: "The abstract should be presented divided into subheadings (unless it is a mini or full review article)". Kindly check and confirm whether the corresponding authors and mail ID are correctly identified. Confirmed.

Co-delivery of Phagocytosis Checkpoint Silencer and Stimulator of Interferon Genes Agonist for Synergetic Cancer Immunotherapy

Efficient capture and presentation of tumor antigens by antigen-presenting cells (APCs), especially dendritic cells (DCs), are crucial for activating the anti-tumor immunity. However, APCs are immunosuppressed in the tumor microenvironment, which hinders the tumor elimination. To reprogram APCs for inducing strong anti-tumor immunity, we report here a co-delivery immunotherapeutic strategy targeting the phagocytosis checkpoint (signal regulatory protein α, SIRPα) and stimulator of interferon genes (STING) of APCs to jointly enhance their ability of capturing and presenting tumor antigens. In brief, a small interfering RNA targeting SIRPα (siSIRPα) and a STING agonist (cGAMP) were co-delivered into APCs by the encapsulation into poly(ethylene glycol)-b-poly(lactide-co-glycolide)-based polymeric nanoparticles (NP_{siSIRPα/cGAMP}). siSIRPα-mediated SIRPα silence promoted APCs to actively capture tumor antigens by engulfing tumor cells. The cGAMP-stimulated STING signaling pathway further enhanced the functions of APCs, thereby increased the activation and expansion of CD8⁺ T cells. Using ovalbumin (OVA)-expressing melanoma as a model, we demonstrated that NP_{siSIRPα/cGAMP} stimulated the activation of OVA-specific CD8⁺ T cells and induced holistic anti-tumor immune responses by reversing the immunosuppressive phenotype of APCs. Collectively, this co-delivery strategy synergistically enhanced the functions of APCs and can be extended to the treatment of tumors with poor immunogenicity.

Nanotechnology synergized immunoengineering for cancer

Novel strategies modulating the immune system yielded enhanced anticancer responses and improved cancer survival. Nevertheless, the success rate of immunotherapy in cancer treatment has been below expectation(s) due to unpredictable efficacy and off-target effects from systemic dosing of immunotherapeutic(s). As a result, there is an unmet clinical need for improving conventional immunotherapy. Nanotechnology offers several new strategies, multimodality, and multiplex biological targeting advantage to overcome many of these challenges. These efforts enable programming the pharmacodynamics, pharmacokinetics, and delivery of immunomodulatory agents/co-delivery of compounds to prime at the tumor sites for improved therapeutic benefits. This review provides an overview of the design and clinical principles of biomaterials driven nanotechnology and their potential use in personalized nanomedicines, vaccines, localized tumor modulation, and delivery strategies for cancer immunotherapy. In this review, we also summarize the latest highlights and recent advances in combinatorial therapies availed in the treatment of cold and complicated tumors. It also presents key steps and parameters implemented for clinical success. Finally, we analyse, discuss, and provide clinical perspectives on the integrated opportunities of nanotechnology and immunology to achieve synergistic and durable responses in cancer treatment.

Novel fully human anti-CD47 antibodies stimulate phagocytosis and promote elimination of AML cells

Although most patients with acute myeloid leukemia (AML) enter remission after induction chemotherapy, the risk of relapse remains considerable. Therefore, some novel therapeutic strategies are still required. This study found that the overexpression of CD47 on AML cells was at least twofold more than that on normal bone marrow (NBM) cells in 81% (17/21) of the investigated patients; no patients had lower expression level of CD47 compared with healthy donors. The study also demonstrated that blocking the CD47/SIRPα (signal regulatory protein α) signal with the established novel fully human anti-CD47 monoclonal antibodies increased the phagocytosis of AML cells by macrophages in vitro. Furthermore, in vivo experiments showed that the novel fully human anti-CD47 monoclonal antibodies could significantly prolong the survival time of mice. Overall, the novel fully human anti-CD47 antibodies could block CD47/SIRPα interaction, increase macrophage-mediated phagocytosis, and enhance the elimination of AML cells.

Berberine exerts anti-tumor activity in diffuse large B-cell lymphoma by modulating c-myc/CD47 axis

Diffuse large B-cell lymphoma (DLBCL) is the most common subtype of non-Hodgkin lymphoma (NHL) with high clinical heterogeneity and poor prognosis. Immune escape mediated by CD47 overexpression contributes to the limited efficacy of rituximab, an anti-CD20 antibody, which indicates a target to improve the efficacy of DLBCL treatment. Here, we validated berberine, a natural compound, as a suppressor of CD47 and revealed the involved mechanism and biological function in DLBCL. Berberine downregulated the expression of CD47 in DLBCL at the transcriptional level by suppressing c-myc expression. Berberine-induced CD47 inhibition enhanced the phagocytosis of macrophages, thereby eliminating DLBCL cells in vitro and in vivo. Interestingly, berberine enhanced the efficiency of anti-CD47 antibody and rituximab-mediated phagocytosis. Moreover, a novel prognostic model based on the combination of CD47 and CD68, a biomarker of macrophages, was established in DLBCL. Our results highlighted for the first time that berberine could restore macrophage function in the tumor microenvironment, enhance rituximab-mediated phagocytosis and promote anti-CD47 antibody function via suppressing CD47 expression, which revealed a new anti-tumor mechanism of berberine and provided novel insights into the rituximab-based immunochemotherapy and CD47-targeted immunotherapy in DLBCL.

Cancer Nanopharmaceuticals: Physicochemical Characterization and In Vitro/In Vivo Applications

Physicochemical, pharmacokinetic, and biopharmaceutical characterization tools play a key role in the assessment of nanopharmaceuticals' potential imaging analysis and for site-specific delivery of anti-cancers to neoplastic cells/tissues. If diagnostic tools and therapeutic approaches are combined in one single nanoparticle, a new platform called nanotheragnostics is generated. Several analytical technologies allow us to characterize nanopharmaceuticals and nanoparticles and their properties so that they can be properly used in cancer therapy. This paper describes the role of multifunctional nanoparticles in cancer diagnosis and treatment, describing how nanotheragnostics can be useful in modern chemotherapy, and finally, the challenges associated with the commercialization of nanoparticles for cancer therapy.

Combinatory Delivery of Etoposide and siCD47 in a Lipid Polymer Hybrid Delays Lung Tumor Growth in an Experimental Melanoma Lung Metastatic Model

This study investigated the feasibility of lipid polymer hybrid nanoparticles (LPH) as a platform for the combinatorial delivery of small interfering RNA (siRNA) and etoposide (Eto). Different Eto loaded LPH formulations (LPH _Eto ) are prepared. The optimized cationic LPH _Eto  with a particle size of 109.66 ± 5.17 nm and Eto entrapment efficiency (EE %) of 80.33 ± 2.55 is used to incorporate siRNA targeting CD47 (siCD47), a do not eat me marker on the surface of cancer cells. The siRNA-encapsulating LPH (LPH _siNEG-Eto ) has a particle size of 115.9 ± 4.11 nm and siRNA EE % of 63.54 ± 4.36 %. LPHs improved the cellular uptake of siRNA in a dose- and concentration-dependent manner. Enhanced cytotoxicity (3.8-fold higher than Eto solution) and high siRNA transfection efficiency (≈50 %) are obtained. An in vivo biodistribution study  showed a preferential uptake of the nanosystem into lung, liver, and spleen. In an experimental pseudo-metastatic B16F10 lung tumor model, a superior therapeutic outcome can be observed in mice treated with combinatory therapy. Immunological studies revealed elevated CD4+, CD8+ cells, and macrophages in the lung following combinatory treatment. The study suggests the potential of the current system for combinatory chemotherapy and immunotherapy for the treatment of lung cancer or lung metastasis.

Restoration of miR-340 controls pancreatic cancer cell CD47 expression to promote macrophage phagocytosis and enhance antitumor immunity

Background

Immune checkpoint blockade has emerged as a potential cancer immunotherapy. The “don’t eat me” signal CD47 in cancer cells binds signal regulatory protein-α on macrophages and prevents their phagocytosis. The role of miR-340 in pancreatic ductal adenocarcinoma (PDAC), especially in tumor immunity, has not been explored. Here, we examined the clinical and biological relevance of miR-340 and the molecular pathways regulated by miR-340 in PDAC.

Methods

CD47 and miR-340 expression and the relationship with cancer patient survival were analyzed by bioinformatics. The mechanism of miR-340 action was explored through bioinformatics, luciferase reporter, qRT-PCR and western blot analyses. The effects of miR-340 on cancer cells were analyzed in terms of apoptosis, proliferation, migration and phagocytosis by macrophages. In vivo tumorigenesis was studied in orthotopic and subcutaneous models, and immune cells from the peripheral and tumor immune microenvironments were analyzed by flow cytometry. Depletion of macrophages was used to verify the role of macrophages in impacting the function of miR-340 in tumor progression.

Results

miR-340 directly regulates and inversely correlates with CD47, and it predicts patient survival in PDAC. The restoration of miR-340 expression in pancreatic cancer cells was sufficient to downregulate CD47 and promote phagocytosis of macrophages, further inhibiting tumor growth. The overexpression of miR-340 promoted macrophages to become M1-like phenotype polarized in peripheral and tumor immune microenvironments and increased T cells, especially CD8⁺ T cells, contributing to the antitumor effect of miR-340.

Conclusions

miR-340 is a key regulator of phagocytosis and antitumor immunity, and it could offer a new opportunity for immunotherapy for PDAC.

Advances in siRNA delivery strategies for the treatment of MDR cancer

RNA interference (RNAi) represents a promising therapeutic method that uses siRNA for cancer treatment. Although the RNAi technique has been increasingly used for clinical trials, systemic siRNA delivery into targeted cells is still challenging. The barriers impeding siRNA therapeutics delivery and impacting the treatment outcome must overcome with negligible systemic toxicity for a desirable and successful delivery of siRNA to MDR cancer cells. Nano delivery strategies have been investigated for nanocarrier functionalization, cancer immunotherapy and cancer targeting. Lipid nanoparticles (LNPs), dynamic polyconjugates (DPC™), GalNAc-siRNA conjugates, exosome and RBC systems have shown potential for efficient delivery of siRNA to cancer cells. Delivery of siRNA to tumor cells, immune cells to regulate T cell functions for immunotherapy are promising approaches.

Targeting CD47 Inhibits Tumor Development and Increases Phagocytosis in Oral Squamous Cell Carcinoma

BACKGROUND

Our previous work demonstrated upregulated CD47 in Oral Squamous Cell Carcinoma (OSCC).

OBJECTIVE

In the present study, we aimed to investigate the effects of CD47 on tumor cell development and phagocytosis in OSCC and elucidate the underlying mechanisms.

METHODS

The proliferation, apoptosis, migration, and invasion of oral cancer cells were analyzed after knocking down the expression of CD47. The effects of CD47 on tumor development were also evaluated using a murine model of OSCC. The involvement of CD47 in the phagocytosis of oral cancer cells was identified.

RESULTS

Cell proliferation was suppressed by knocking down the expression of CD47 in human OSCC cell line Cal-27 cells but there was no change in the apoptosis rate. Moreover, impaired expression of CD47 inhibited the migration and invasion of Cal-27 cells. Furthermore, we found that nude mice injected with CD47 knockeddown Cal-27 cells displayed decreased tumor volumes at week 9 compared to xenograft transplantations of blank Cal-27 cells. In addition, in vitro phagocytosis of Cal-27 cells by macrophages was significantly enhanced after the knockdown of CD47, which positively correlated with compromised STAT3/JAK2 signaling.

CONCLUSION

In summary, the knockdown of CD47 downregulated the development of OSCC and increased the phagocytosis of Cal-27 cells, indicating that CD47 might be a promising therapeutic target.