Breaking the Tumor Chronic Inflammation Balance with a Programmable Release and Multi-Stimulation Engineering Scaffold for Potent Immunotherapy.

Tumor-associated chronic inflammation severely restricts the efficacy of immunotherapy in cold tumors. Here, a programmable release hydrogel-based engineering scaffold with multi-stimulation and reactive oxygen species (ROS)-response (PHOENIX) is demonstrated to break the chronic inflammatory balance in cold tumors to induce potent immunity. PHOENIX can undergo programmable release of resiquimod and anti-OX40 under ROS. Resiquimod is first released, leading to antigen-presenting cell maturation and the transformation of myeloid-derived suppressor cells and M2 macrophages into an antitumor immune phenotype. Subsequently, anti-OX40 is transported into the tumor microenvironment, leading to effector T-cell activation and inhibition of Treg function. PHOENIX consequently breaks the chronic inflammation in the tumor microenvironment and leads to a potent immune response. In mice bearing subcutaneous triple-negative breast cancer and metastasis models, PHOENIX effectively inhibited 80% and 60% of tumor growth, respectively. Moreover, PHOENIX protected 100% of the mice against TNBC tumor rechallenge by electing a robust long-term antigen-specific immune response. An excellent inhibition and prolonged survival in PHOENIX-treated mice with colorectal cancer and melanoma is also observed. This work presents a potent therapeutic scaffold to improve immunotherapy efficiency, representing a generalizable and facile regimen for cold tumors.

Reversing cancer immunoediting phases with a tumor-activated and optically reinforced immunoscaffold.

In situ vaccine (ISV) is a promising immunotherapeutic tactic due to its complete tumoral antigenic repertoire. However, its efficiency is limited by extrinsic inevitable immunosuppression and intrinsic immunogenicity scarcity. To break this plight, a tumor-activated and optically reinforced immunoscaffold (TURN) is exploited to trigger cancer immunoediting phases regression, thus levering potent systemic antitumor immune responses. Upon response to tumoral reactive oxygen species, TURN will first release RGX-104 to attenuate excessive immunosuppressive cells and cytokines, and thus immunosuppression falls and immunogenicity rises. Subsequently, intermittent laser irradiation-activated photothermal agents (PL) trigger abundant tumor antigens exposure, which causes immunogenicity springs and preliminary infiltration of T cells. Finally, CD137 agonists from TURN further promotes the proliferation, function, and survival of T cells for durable antitumor effects. Therefore, cancer immunoediting phases reverse and systemic antitumor immune responses occur. TURN achieves over 90 % tumor growth inhibition in both primary and secondary tumor lesions, induces potent systemic immune responses, and triggers superior long-term immune memory in vivo. Taken together, TURN provides a prospective sight for ISV from the perspective of immunoediting phases.

A programmable releasing versatile hydrogel platform boosts systemic immune responses via sculpting tumor immunogenicity and reversing tolerogenic dendritic cells.

Immunogenicity improvement is a valuable strategy for tumor immunotherapy. However, immunosuppressive factors bestow tolerogenic phenotype on tumor-infiltrating DCs, which exhibit weak antigen presentation and strong anti-inflammatory cytokines secretion abilities, limiting the effectiveness of tumor immunotherapy even if the tumor has adequate immunogenicity. Herein, we designed a programmable releasing versatile hydrogel platform (PIVOT) to sculpt tumor immunogenicity, increase intratumoral DCs and cDC1s abundance, and reverse the tolerogenic phenotype of DCs, thus promoting their maturation for boosting innate and adaptive immune responses. Responsive to tumoral reactive oxygen species (ROS), the hydrogel splits and promotes the activation of DCs and macrophages. Then, oxaliplatin is first released from PIVOT to sculpt tumor immunogenicity by inducing immunogenic cell death (ICD) and causing tumoral DNA fragments exposure simultaneously. Subsequently, the impaired DNA fragments bind to high mobility group protein 1 (HMGB1) forming the DNA-HMGB1 complex. Moreover, exogenous FMS-like tyrosine kinase 3 ligand (Flt-3L) recruits masses of DCs, especially cDC1s, which will endocytose the complex benefiting from TIM-3 blockade (αTIM3) that can reverse tolerogenic DCs. Finally, the endocytosis activates the cGAS-STING pathway of cDC1s, which promotes the secretion of type I IFN that triggers innate immune responses, and CXCL9 which recruits CD8+ effector T cells to initiate the following adaptive immune response against tumor progress. PIVOT achieves nearly 90 % tumor growth inhibition and induces systemic antitumor immune responses. In conclusion, this study focuses on ICD-mediated tumor immunogenicity sculpture and nucleic acid endocytosis-involved tolerogenic DCs reversal, providing a novel paradigm for enhancing DCs-based antitumor immune responses.

Antigenicity and adjuvanticity co-reinforced personalized cell vaccines based on self-adjuvanted hydrogel for post-surgical cancer vaccination.

Cancer vaccine-based postsurgical immunotherapy is emerging as a promising approach in patients following surgical resection for inhibition of tumor recurrence. However, low immunogenicity and insufficient cancer antigens limit the widespread application of postoperative cancer vaccines. Here, we propose a "trash to treasure" cancer vaccine strategy to enhance postsurgical personalized immunotherapy, in which antigenicity and adjuvanticity of purified surgically exfoliated autologous tumors (with whole antigen repertoire) were co-reinforced. In the antigenicity and adjuvanticity co-reinforced personalized vaccine (Angel-Vax), polyriboinosinic: polyribocytidylic acid (pIC) and tumor cells that have undergone immunogenic death are encapsulated in a self-adjuvanted hydrogel formed by cross-linking of mannan and polyethyleneimine. Angel-Vax exhibits an enhanced capacity on antigen-presenting cells stimulation and maturation compared to its individual components in vitro. Immunization with Angel-Vax provokes an efficient systemic cytotoxic T-cell immune response, contributing to the satisfied prophylactic and therapeutic efficacy in mice. Furthermore, when combined with immune checkpoint inhibitors (ICI), Angel-Vax effectively prevented postsurgical tumor recurrence, as evidenced by an increase in median survival of approximately 35% compared with ICI alone. Unlike the cumbersome preparation process of postoperative cancer vaccines, the simple and feasible approach herein may represent a general strategy for various kinds of tumor cell-based antigens in the inhibition of postsurgical tumor relapse by reinforced immunogenicity.

A tactical nanomissile mobilizing antitumor immunity enables neoadjuvant chemo-immunotherapy to minimize postsurgical tumor metastasis and recurrence.

Neoadjuvant chemotherapy has become an indispensable weapon against high-risk resectable cancers, which benefits from tumor downstaging. However, the utility of chemotherapeutics alone as a neoadjuvant agent is incapable of generating durable therapeutic benefits to prevent postsurgical tumor metastasis and recurrence. Herein, a tactical nanomissile (TALE), equipped with a guidance system (PD-L1 monoclonal antibody), ammunition (mitoxantrone, Mit), and projectile bodies (tertiary amines modified azobenzene derivatives), is designed as a neoadjuvant chemo-immunotherapy setting, which aims at targeting tumor cells, and fast-releasing Mit owing to the intracellular azoreductase, thereby inducing immunogenic tumor cells death, and forming an in situ tumor vaccine containing damage-associated molecular patterns and multiple tumor antigen epitopes to mobilize the immune system. The formed in situ tumor vaccine can recruit and activate antigen-presenting cells, and ultimately increase the infiltration of CD8+ T cells while reversing the immunosuppression microenvironment. Moreover, this approach provokes a robust systemic immune response and immunological memory, as evidenced by preventing 83.3% of mice from postsurgical metastasis or recurrence in the B16-F10 tumor mouse model. Collectively, our results highlight the potential of TALE as a neoadjuvant chemo-immunotherapy paradigm that can not only debulk tumors but generate a long-term immunosurveillance to maximize the durable benefits of neoadjuvant chemotherapy.

Tumor Microenvironment-Activated Hydrogel Platform with Programmed Release Property Evokes a Cascade-Amplified Immune Response against Tumor Growth, Metastasis and Recurrence.

In situ tumor vaccines (ITV) have been recognized as a promising antitumor strategy since they contain the entire tumor-specific antigens, avoiding tumor cells from evading immune surveillance due to antigen loss. However, the therapeutic benefits of ITV are limited by obstacles such as insufficient antigen loading, inadequate immune system activation, and immunosuppressive tumor microenvironments (TME). Herein, a tumor microenvironment-activated hydrogel platform (TED-Gel) with programmed drug release property is constructed for cascaded amplification of the anti-tumor immune response elicited by ITV. Both doxorubicin (Dox) and cytosine-phosphate-guanosine oligodeoxynucleotides (CpG) are released first, in which Dox induces immunogenic tumor cell death causing additional tumor antigen release and leading the dying primary tumor cells into autologous tumor vaccine, and the released CpG promotes antigen presenting cell activation. Subsequently, the decomposed scaffold materials in conjunction with CpG, turn the anti-inflammatory M2-like macrophages into the M1 type, reversing the immunosuppressive TME. With decomposition of the TED-Gel, large amounts of macromolecule anti-PD-L1 antibodies are liberated, reinvigorating the exhausted effector T cells. In vivo studies demonstrate that TED-Gel significantly inhibits the primary, distant and rechallenged tumor growth. Overall, the simple and powerful TED-Gel provides an alternative strategy for the future development of tumor vaccines with broad application.

Multifunctional light-activatable nanocomplex conducting temperate-heat photothermal therapy to avert excessive inflammation and trigger augmented immunotherapy.

Photothermal therapy (PTT) has been known as an effective weapon against cancer. However, the necrosis induced by hyperthermia post PTT can trigger excessive inflammation response and arouse tumor self-protection resulting in tumor immunosuppression, metastasis and recurrence. To settle this issue, we here reported a multifunctional light-activatable nanocomplex (MILAN) to avoid hyperthermia and achieve temperate-heat PTT for extensive apoptosis, but not necrosis, and further antitumor immune response augmentation to inhibit metastasis and recurrence. Upon NIR irradiation, MILAN would controllably maintain around 43 °C, thus evoking the temperature-triggered phase transformation for the controllable drug release. Then, the released gambogic acid broke the thermoresistance of tumor cells, realizing enhanced apoptosis. Thereafter, the generated tumor-associated antigen accompanied with MILAN could facilitate dendritic cells (DCs) maturation for improved antigen presentation. Furthermore, MILAN promoted the tumor perfusion of DCs and T lymphocytes in triple-negative breast cancer (TNBC) models. Simultaneously, the immunosuppressive microenvironment was relieved and a strong systemic immune response was elicited against tumor progress through MILAN. Consequently, systemic immunity and persistent immune memory effect were fortified for pronounced cancer metastasis and recurrence inhibition. This work tactfully avoids the side effects of hyperthermia and brought a novel insight into cancer immunotherapy against TNBC.

Lanthanide-Nucleotide Coordination Nanoparticles for STING Activation.

Activation of the stimulator of interferon genes (STING) is essential for blocking viral infections and eliciting antitumor immune responses. Local injection of synthetic STING agonists, such as 2'3'-cGAMP [cGAMP = cyclic 5'-guanosine monophosphate (cGMP)-adenosine monophosphate (AMP)], is a promising approach to enhance antiviral functions and cancer immunotherapy. However, the application of such agonists has been hindered by complicated synthetic procedures, high doses, and unsatisfactory systemic immune responses. Herein, we report the design and synthesis of a series of 2'3'-cGAMP surrogates in nanoparticle formulations formed by reactions of AMP, GMP, and coordinating lanthanides. These nanoparticles can stimulate the type-I interferon (IFN) response in both mouse macrophages and human monocytes. We further demonstrate that the use of europium-based nanoparticles as STING-targeted adjuvants significantly promotes the maturation of mouse bone-marrow-derived dendritic cells and major histocompatibility complex class I antigen presentation. Dynamic molecular docking analysis revealed that these nanoparticles bind with high affinity to mouse STING and human STING. Compared with soluble ovalbumin (OVA), subcutaneously immunized europium-based nanovaccines exhibit significantly increased production of primary and secondary anti-OVA antibodies (∼180-fold) in serum, as well as IL-5 (∼28-fold), IFN-γ (∼27-fold), and IFN-α/ß (∼4-fold) in splenocytes ex vivo. Compared with the 2'3'-cGAMP/OVA formulation, subcutaneous administration of nanovaccines significantly inhibits B16F10-OVA tumor growth and prolongs the survival of tumor-bearing mice in both therapeutic and protective models. Given the rich supramolecular chemistry with lanthanides, this work will enable a readily accessible platform for potent humoral and cellular immunity while opening new avenues for cost-effective, highly efficient therapeutic delivery of STING agonists.

A spontaneous multifunctional hydrogel vaccine amplifies the innate immune response to launch a powerful antitumor adaptive immune response.

Substantial progress has been made with cancer immunotherapeutic strategies in recent years, most of which mainly rely on enhancing the T cell response. However, sufficient tumor antigen information often cannot be presented to T cells, resulting in a failed effector T cell response. The innate immune system can effectively recognize tumor antigens and then initiate an adaptive immune response. Here, we developed a spontaneous multifunctional hydrogel (NOCC-CpG/OX-M, Ncom Gel) vaccine to amplify the innate immune response and harness innate immunity to launch and maintain a powerful adaptive immune response. Methods: Ncom Gel was formed by a Schiff base reaction between CpG-modified carboxymethyl chitosan (NOCC-CpG) and partially oxidized mannan (OX-M). The effects of the Ncom Gel vaccine on DCs and macrophages in vitro and antigen-specific humoral immunity and cellular immunity in vivo were studied. Furthermore, the antitumor immune response of the Ncom Gel vaccine and its effect on the tumor microenvironment were evaluated. Results: The Ncom Gel vaccine enhanced antigen presentation to T cells by facilitating DC uptake and maturation and inducing macrophages to a proinflammatory subtype, further leading to a T cell-mediated adaptive immune response. Moreover, the innate immune response could be amplified via the promotion of antigen-specific antibody production. The Ncom Gel vaccine reversed the tumor immune microenvironment to an inflamed phenotype and showed a significant antitumor response in a melanoma model. Conclusions: Our research implies the potential application of injectable hydrogels as a platform for tumor immunotherapy. The strategy also opens up a new avenue for multilayered cancer immunotherapy.

Self-Adjuvanted Molecular Activator (SeaMac) Nanovaccines Promote Cancer Immunotherapy.

Neoantigen-based immunotherapy is a promising treatment option for many types of cancer. However, its efficacy and abscopal effect are limited by impotent neoantigens, high treatment costs, and complications due to action of adjuvants. Here, the design and synthesis of nanovaccines are reported, based on self-adjuvanted, polymer nanoparticles with in vivo neoantigen-harvesting and molecular activating capabilities. These nanovaccines inhibit tumor growth significantly and prolong the survival of tumor-bearing mice in both colon carcinoma 26 (CT26) and B16-F10 tumor models. Mechanistic studies suggest that as-synthesized nanovaccines can promote dendritic cell maturation and accumulation expeditiously in lymph nodes, leading to the expansion of cytotoxic CD8+ T cells. Moreover, these nanovaccines elicit abscopal effects in CT26 and B16-F10 tumors without the need for adjuvants or immune checkpoint inhibitors. Combined with an anti-PD-L1 antibody, nanovaccines can evoke robust, long-term memory immune response, as evidenced by tumor growth inhibition and high survival rates (∼ 67%) over 90 days. These results highlight the potential of using self-adjuvanted nanovaccines as a simple, safe, and affordable strategy to boost neoantigen-based cancer immunotherapy.

Hyaluronic Acid Oligosaccharides Improve Myocardial Function Reconstruction and Angiogenesis against Myocardial Infarction by Regulation of Macrophages.

Myocardial infarction (MI) is identified as one of the major causes of mortality and disability worldwide. For severe myocardial infarction, even advanced forms of clinical intervention often lead to unsatisfactory therapeutic results. Thus, alternative strategies for MI treatment are still desirable. Previously studies reported the capacity of degradative fragment of h-HA (high molecular weight hyaluronic acid), hyaluronan oligosaccharides (<10 disaccharides units, o-HA), for wound healing by influence on angiogenesis, inspiring us to study its potential for myocardial functional recovery against MI. However, there are few reports about o-HA in MI therapy. Methods: In our study, we synthesized o-HA with 6~10 disaccharides (4-5 kDa) by enzymatic degradation and investigated its therapeutic effects on MI. Results: We found that o-HA could reduce infarct size and apoptosis in MI region, also promote myocardial angiogenesis and myocardial function reconstruction in MI mouse model. Furthermore, our results also indicated that o-HA in cardiac improved polarization of M2 type macrophage, removed the inflammatory response caused by neutrophil for accelerating myocardial function reconstruction in vivo. The transcriptomic analyses revealed that o-HA could activate expression of chemokines Ccl2 and Cxcl5 for promoting macrophage polarization and stimulate MAPK and JAK/STAT signaling pathway for compensatory response of myocardial function. Conclusion: Collectively, our results suggested o-HA with 6~10 disaccharides might be a potential agent for reconstruction of cardiac function against MI.

Gambogic Acid-Loaded Polymeric Micelles for Improved Therapeutic Effect in Breast Cancer.

Gambogic acid (GA) possesses good anti-tumor efficacy in preclinical studies, however, its poor hydrophilicity, short blood circulation time and side effect limited its clinical application. In this work, monomethyl poly(ethylene glycol)-poly(ε-caprolactone) (MPEG-PCL) copolymer was synthesized and used to encapsulate GA by a facile one-step solid dispersion and form nano-sized micelles (GA micelles). The GA micelles exhibited small average particle size (29±2 nm), high encapsulation efficiency (92.1±0.3%), and long drug release time-in vitro. Compared to free GA, GA micelles showed superior aqueous dispersity, better tumor cellular uptake, enhanced cytotoxicity and apoptosis induction effect against MCF-7 cells. Furthermore, in vivo studies demonstrated that GA micelles have better antitumor effect in the MCF-7 subcutaneous xenograft tumor model. Histopathological analysis of Ki-67 and TUNEL staining further proved that GA micelles could significantly suppress proliferation as well as increase the apoptosis of tumor cells. These results suggested that GA micelles could potentially improve therapeutic outcomes for breast cancer therapy.

Novel polyethyleneimine-R8-heparin nanogel for high-efficiency gene delivery in vitro and in vivo.

Gene therapy is an efficient and promising approach to treat malignant tumors. However, protecting the nucleic acid from degradation in vivo and efficient delivering it into tumor cells remain challenges that require to be addressed before gene therapy could be applied in clinic. In this study, we prepared novel polyethyleneimine-RRRRRRRR(R8)-heparin (HPR) nanogel as an efficient gene delivery system, which consists of heparin and cell penetrating peptide R8 grafted low-molecule-weight polyethyleneimine (PEI). Due to the shielding effect of heparin, crosslinking PEI-R8 with heparin was designed to diminish the toxicity of the gene delivery system. Meanwhile, a partial of R8 peptide which located on the surface of HPR nanogel could significantly enhance the cellular uptake. The formed HPR/pDNA complex exhibited effective endolysosomal escape, resulting in a high-efficiency transfection. Furthermore, the HPR could deliver the plasmid which could transcribe human TNF-related apoptosis inducing ligand (phTRAIL), into HCT-116 cells and induce significant cell apoptosis. In addition, HPR/phTRAIL complex showed satisfactory antitumor activity in abdominal metastatic colon carcinoma model. Finally, the antitumor mechanism of HPR/phTRAIL was also explored by western blot and histological analysis. The above results suggested that the HPR nanogel could serve as a promising gene delivery system.