Activity In Tumor Microenvironment Research Articles

Hyaluronan-decorated copper-doxorubicin-anlotinib nanoconjugate for targeted synergistic chemo/chemodynamic/antiangiogenic tritherapy against hepatocellular carcinoma

Copper-based nanomaterials show considerable potential in the chemodynamic therapy of cancers. However, their clinical application is restricted by low catalytic activity in tumor microenvironment and copper-induced tumor angiogenesis. Herein, a novel copper-doxorubicin-anlotinib (CDA) nanoconjugate was constructed by the combination of copper-hydrazide coordination, hydrazone linkage and Schiff base bond. The CDA nanoconjugate consists of a copper-3,3′-dithiobis(propionohydrazide)-doxorubicin core and an anlotinib-hyaluronan shell. Benefiting from hyaluronan camouflage and abundant disulfide bonds and Cu2+, the CDA nanoconjugate possessed excellent tumor-targeting and glutathione-depleting abilities and enhanced chemodynamic efficacy. Released doxorubicin significantly improved copper-mediated chemodynamic therapy by upregulating nicotinamide adenine dinucleotide phosphate oxidase 4 expression to increase intracellular H2O2 level. Furthermore, the nanoconjugate produced excessive •OH to induce lipid peroxidation and mitochondrial dysfunction, thus greatly elevating doxorubicin-mediated chemotherapy. Importantly, anlotinib effectively inhibited the angiogenic potential of copper ions. In a word, the CDA nanoconjugate is successfully constructed by combined coordination and pH-responsive linkages, and displays the great potential of copper-drug conjugate for targeted synergistic chemo/chemodynamic/antiangiogenic triple therapy against cancers.

PLOD3 facilitated T cell activation in the colorectal tumor microenvironment and liver metastasis by the TNF-α/ NF-κB pathway

BackgroundColorectal cancer (CRC) has been the third most prevalent cancer worldwide. Liver metastasis is the critical factor for the poor prognosis of CRC. Here, we investigated the expression and role of PLOD3 in CRC.MethodsDifferent liver metastasis models were established by injecting PLOD3 stable knockdown or overexpression CT26 or MC38 mouse CRC cells into the spleen of mice to verify the tumorigenicity and metastasis ability in vivo.ResultsWe identified PLOD3 is significantly overexpressed in liver metastasis samples of CRC. High expression of PLOD3 was significantly associated with poor survival of CRC patients. The knockdown of PLOD3 exhibited remarkable inhibition of proliferation, migration, and invasion in CRC cells, while the opposite results could be found in different PLOD3-overexpressed CRC cells. Stable knockdown of PLOD3 also significantly inhibited liver metastasis of CRC cells in different xenografts models, while stable overexpression of PLOD3 promotes liver metastasis and tumor progression. Further studies showed that PLOD3 facilitated the T cell activation in the tumor microenvironment and affected the TNF-α/ NF-κB pathway.ConclusionsThis study revealed the essential biological functions of PLOD3 in colon cancer progression and metastasis, suggesting that PLOD3 is a promising translational medicine target and bioengineering targeting PLOD3 overcomes CRC liver metastasis.Graphical

RNA-based modulation of macrophage-mediated efferocytosis potentiates antitumor immunity in colorectal cancer

Tumor-associated macrophages play pivotal roles in tumor progression and metastasis. Macrophage-mediated clearance of apoptotic cells (efferocytosis) supports inflammation resolution, contributing to immune evasion in colorectal cancers. To reverse this immunosuppressive process, we propose a readily translatable RNA therapy to selectively inhibit macrophage-mediated efferocytosis in tumor microenvironment. A clinically approved lipid nanoparticle platform (LNP) is employed to encapsulate siRNA for the phagocytic receptor MerTK (siMerTK), enabling selective MerTK inhibition in the diseased organ. Decreased MerTK expression in tumor-associated macrophages results in apoptotic cell accumulation and immune activation in tumor microenvironment, leading to suppressed tumor growth and better survival in both liver and peritoneal metastasis models of colorectal cancers. siMerTK delivery combined with PD-1 blockade further produces enhanced antimetastatic efficacy with reactivated intratumoral immune milieu. Collectively, LNP-based siMerTK delivery combined with immune checkpoint therapy may present a feasible modality for metastatic colorectal cancer therapy.

Inorganic Nanoparticles as Radiosensitizers for Cancer Treatment.

Nanotechnology has expanded what can be achieved in our approach to cancer treatment. The ability to produce and engineer functional nanoparticle formulations to elicit higher incidences of tumor cell radiolysis has resulted in substantial improvements in cancer cell eradication while also permitting multi-modal biomedical functionalities. These radiosensitive nanomaterials utilize material characteristics, such as radio-blocking/absorbing high-Z atomic number elements, to mediate localized effects from therapeutic irradiation. These materials thereby allow subsequent scattered or emitted radiation to produce direct (e.g., damage to genetic materials) or indirect (e.g., protein oxidation, reactive oxygen species formation) damage to tumor cells. Using nanomaterials that activate under certain physiologic conditions, such as the tumor microenvironment, can selectively target tumor cells. These characteristics, combined with biological interactions that can target the tumor environment, allow for localized radio-sensitization while mitigating damage to healthy cells. This review explores the various nanomaterial formulations utilized in cancer radiosensitivity research. Emphasis on inorganic nanomaterials showcases the specific material characteristics that enable higher incidences of radiation while ensuring localized cancer targeting based on tumor microenvironment activation. The aim of this review is to guide future research in cancer radiosensitization using nanomaterial formulations and to detail common approaches to its treatment, as well as their relations to commonly implemented radiotherapy techniques.

Catalase-gold nanoaggregates manipulate the tumor microenvironment and enhance the effect of low-dose radiation therapy by reducing hypoxia

Radiotherapy as a standard method for cancer treatment faces tumor recurrence and antitumoral unresponsiveness. Suppressive tumor microenvironment (TME) and hypoxia are significant challenges affecting efficacy of radiotherapy. Herein, a versatile method is introduced for the preparation of pH-sensitive catalase-gold cross-linked nanoaggregate (Au@CAT) having acceptable stability and selective activity in tumor microenvironment. Combining Au@CAT with low-dose radiotherapy enhanced radiotherapy effects via polarizing protumoral immune cells to the antitumoral landscape. This therapeutic approach also attenuated hypoxia, confirmed by downregulating hypoxia hallmarks, such as hypoxia-inducible factor α-subunits (HIF-α), vascular endothelial growth factor (VEGF), and EGF. Catalase stability against protease digestion was improved significantly in Au@CAT compared to the free catalase. Moreover, minimal toxicity of Au@CAT on normal cells and increased reactive oxygen species (ROS) were confirmed in vitro compared with radiotherapy. Using the nanoaggregates combined with radiotherapy led to a significant reduction of immunosuppressive infiltrating cells such as myeloid-derived suppressor cells (MDSCs) and regulatory T cells (T-regs) compared to the other groups. While, this combined therapy could significantly increase the frequency of CD8+ cells as well as M1 to M2 macrophages (MQs) ratio. The combination therapy also reduced the tumor size and increased survival rate in mice models of colorectal cancer (CRC). Our results indicate that this innovative nanocomposite could be an excellent system for catalase delivery, manipulating the TME and providing a potential therapeutic strategy for treating CRC.

RNF31 promotes tumorigenesis via inhibiting RIPK1 kinase-dependent apoptosis.

It is well established that interferon (IFN) and tumor necrosis factor (TNF) could synergistically promote antitumor toxicity and avoid resistance of antigen-negative tumors during cancer immunotherapy. The linear ubiquitin chain assembly complex (LUBAC) has been widely known to regulate receptor-interacting protein kinase-1(RIPK1) kinase activity and TNF-mediated cell death during inflammation and embryogenesis. However, whether LUBAC and RIPK1 kinase activity in tumor microenvironment could regulate antitumor immunity are still not very clear. Here, we demonstrated a cancer cell-intrinsic role of LUBAC complex in tumor microenvironment to promote tumorigenesis. Lacking LUBAC component RNF31 in B16 melanoma cells but not immune cells including macrophages or dendritic cells greatly impaired tumor growth by increasing intratumoral CD8+ T cells infiltration. Mechanistically, we found that tumor cells without RNF31 shown severe apoptosis-mediated cell death caused by TNFα/IFNγ in the tumor microenvironment. Most importantly, we found that RNF31 could limit RIPK1 kinase activity and further prevent tumor cell death in a transcription-independent manner, suggesting a crucial role of RIPK1 kinase activity in tumorigenesis. Together, our results demonstrate an essential role of RNF31 and RIPK1 kinase activity in tumorigenesis and imply that RNF31 inhibition could be harnessed to enhance antitumor toxicity during tumor immunotherapy.

Development and Validation of a Prognostic Risk Model Based on Nature Killer Cells for Serous Ovarian Cancer.

Nature killer (NK) cells are increasingly considered important in tumor microenvironment, but their role in predicting the prognosis of ovarian cancer has not been revealed. This study aimed to develop a prognostic risk model for ovarian cancer based on NK cells. Firstly, differentially expressed genes (DEGs) of NK cells were found by single-cell RNA-sequencing dataset analysis. Based on six NK-cell DEGs identified by univariable, Lasso and multivariable Cox regression analyses, a prognostic risk model for serous ovarian cancer was developed in the TCGA cohort. This model was then validated in three external cohorts, and evaluated as an independent prognostic factor by multivariable Cox regression analysis together with clinical characteristics. With the investigation of the underlying mechanism, a relation between a higher risk score of this model and more immune activities in tumor microenvironment was revealed. Furthermore, a detailed inspection of infiltrated immunocytes indicated that not only quantity, but also the functional state of these immunocytes might affect prognostic risk. Additionally, the potential of this model to predict immunotherapeutic response was exhibited by evaluating the functional state of cytotoxic T lymphocytes. To conclude, this study introduced a novel prognostic risk model based on NK-cell DEGs, which might provide assistance for the personalized management of serous ovarian cancer patients.

Tumor targeted delivery of mycobacterial adjuvant encapsulated chitosan nanoparticles showed potential anti-cancer activity and immune cell activation in tumor microenvironment.

Targeting immunotherapeutics inside the tumor microenvironment (TME) with intact biological activity remains a pressing issue. Mycobacterium indicus pranii (MIP), an approved adjuvant therapy for leprosy has exhibited promising results in clinical trials of lung (NSCLC) and bladder cancer. Whole MIP as well as its cell wall fraction have shown tumor growth suppression and enhanced survival in mice model of melanoma, when administered peritumorally. Clinically, peritumoral delivery remains a procedural limitation. In this study, a tumor targeted delivery system was designed, where chitosan nanoparticles loaded with MIP adjuvants, when administered intravenously showed preferential accumulation within the TME, exploiting the principle of enhanced permeability and retention effect. Bio-distribution studies revealed their highest concentration inside the tumor after 6h of administration. Interestingly, MIP adjuvant nano-formulations significantly reduced the tumor volume in the treated groups and increased the frequency of activated immune cells inside the TME. For chemoimmunotherapeutics studies, MIP nano-formulation was combined with standard dosage regimen of Paclitaxel. Combined therapy exhibited a further reduction in tumor volume relative to either of the MIP nano formulations. From this study a three-pronged strategy emerged as the underlying mechanism; chitosan and Paclitaxel have shown direct role in tumor cell death and the MIP nano-formulation activates the tumor residing immune cells which ultimately leads to the reduced tumor growth.

Platinum‐Based TREM2 Inhibitor Suppresses Tumors by Remodeling the Immunosuppressive Microenvironment

AbstractTriggering receptor expressed on myeloid cells‐2 (TREM2) is a key pro‐tumorigenic marker of tumor‐infiltrating macrophages, showing potent immunosuppressive activity in tumor microenvironment. A platinum(IV) complex OPA derived from oxaliplatin (OP) and artesunate (ART) exhibited direct cytotoxicity against human colon cancer cells and immunomodulatory activity to inhibit TREM2 on macrophages in vitro and vivo. Furthermore, OPA deterred the tumor growth in mouse models bearing MC38 colorectal tumor by reducing the number of CD206+ and CX3CR1+ immunosuppressive macrophages; it also promoted the expansion and infiltration of immunostimulatory dendritic, cytotoxic T, and natural killer cells. OPA is the first small‐molecular TREM2 inhibitor capable of relieving immunosuppressive tumor microenvironment and enhancing chemical anticancer efficiency of a platinum drug, thus showing typical characteristics of a chemoimmunotherapeutic agent.

Platinum-Based TREM2 Inhibitor Suppresses Tumors by Remodeling the Immunosuppressive Microenvironment.

Triggering receptor expressed on myeloid cells-2 (TREM2) is a key pro-tumorigenic marker of tumor-infiltrating macrophages, showing potent immunosuppressive activity in tumor microenvironment. A platinum(IV) complex OPA derived from oxaliplatin (OP) and artesunate (ART) exhibited direct cytotoxicity against human colon cancer cells and immunomodulatory activity to inhibit TREM2 on macrophages in vitro and vivo. Furthermore, OPA deterred the tumor growth in mouse models bearing MC38 colorectal tumor by reducing the number of CD206+ and CX3 CR1+ immunosuppressive macrophages; it also promoted the expansion and infiltration of immunostimulatory dendritic, cytotoxic T, and natural killer cells. OPA is the first small-molecular TREM2 inhibitor capable of relieving immunosuppressive tumor microenvironment and enhancing chemical anticancer efficiency of a platinum drug, thus showing typical characteristics of a chemoimmunotherapeutic agent.

Immunotherapeutic Implications of Toll-like Receptors Activation in Tumor Microenvironment

Toll-like receptors (TLRs) play an important role between innate and adaptive immunity as one of the pattern recognition receptors (PRRs). Both immune cells and tumor cells express TLRs, and the same TLR molecule is expressed in different cells with different roles. TLR activation in the tumor microenvironment mostly has a dual role in tumor progression during chronic inflammation. Clinically, the therapeutic efficacy of most cancer immunotherapy strategies is restricted by the suppressive immune infiltrative environment within the tumor. Therefore, activation of TLRs in innate immune cells has the potential to eradicate tumors lacking T-cell infiltration. TLR agonists have served as important immunomodulators of cancer immunotherapy through immune responses and reprogramming the tumor suppressive microenvironment. Meanwhile, considering the complex interaction of TLRs with the tumor microenvironment, a combined approach of cancer immunotherapy and nanotechnology has been adopted to improve cancer immunotherapy not only by combining multiple drug combinations, but also by targeting the tumor microenvironment using nanoparticles. Many clinical trials are underway to improve antitumor activity through combination with other immunotherapies. In this review, we provide a comprehensive and detailed overview of the immunotherapeutic implications of TLRs activation in tumor microenvironment, highlighting its great potential to be an important tool for cancer immunotherapy.

Versatile BP/Pd-FPEI-CpG nanocomposite for "three-in-one" multimodal tumor therapy

Multimodal nanocatalytic therapy has shown promising potential in cancer treatments. However, to design an effective multimodal nanocatalytic modality, with a deep understanding of synergistic therapy, remains a grand challenge. Herein, we propose an innovative “three-in-one” multimodal strategy with integrated photothermal/photodynamic/chemodynamic modalities for tumor-specific treatment, by rationally constructing a multifunctional two-dimensional (2D) nanoplatform based on the black phosphorous (BP)/Pd nanosheets (NSs) via in-situ growth. Interestingly, such a hybridization of different types of 2D NSs mediates formation of the Pd-P coordination bonds. With strong interfacial Pd-P interaction, the heterostructured NSs display enhanced cascade enzymatic activities in tumor microenvironment, leading to sufficient generation of reactive oxygen species (ROS) as therapeutic species including cytotoxic superoxide (O2•−) radicals by successive catalase-/oxidase-catalysis, and deleterious singlet oxygen (1O2) radicals under light irradiation. The incorporation of Pd also improved the photothermal activity of the material. Furthermore, by facile functionalization with fluoro-polyethyleneimine (FPEI) and loading of cytosine-phosphate-guanine (CpG) as an immune adjuvant, the versatilities of this unique 2D hetero-nanoplatform are further extended, strikingly improving therapeutic efficacy for tumor cells, and simultaneously avoiding significant damage to normal tissues. The work provides useful insights into the design of new 2D nanoplatforms for multimodal tumor treatment.

Propofol enhances the sensitivity of glioblastoma cells to temozolomide by inhibiting macrophage activation in tumor microenvironment to down-regulate HIF-1α expression

Temozolomide (TMZ) is the first-line drug for the clinical treatment of glioblastoma (GBM), but drug resistance limits its treatment benefits. This study was intended to investigate whether propofol could restrict the resistance of GBM cells to TMZ and uncover the underlying mechanisms. Human GBM cell line U251 and TMZ-resistant U251/TMZ cell line were transplanted into mice to construct GBM and TMZ-resistant GBM xenograft tumors. Tumor growth in mice was monitored, and the tumor tissues were collected for biochemical analysis. THP-1 cell differentiated into M0 subtype macrophage using phorbol 12-myristate 13-acetate (PMA). The culture medium of M0 macrophage was collected for treating U251 cells with the presence or absence of propofol or propofol + DMOG (HIF-1α activator). Results showed that propofol significantly enhanced the inhibitory effect of TMZ on tumor growth, macrophage infiltration and inflammation in TMZ-resistant GBM xenograft tumors in vivo. Compared with GBM xenograft tumors, higher expression of HIF-1α, O6-methylguanine-DNA methyltransferase (MGMT), p-p65 and cyclooxygenase 2 (Cox2) was observed in TMZ-resistant GBM xenograft tumors, but propofol co-treatment markedly reduced the expression of these proteins. In in vitro experiments, culture medium from M0 macrophage promoted U251 cell survival, inflammation and expression of HIF-1α, MGMT, p65 and Cox2, whereas inhibited cell apoptosis. However, propofol suppressed the PMA-induced THP-1 M0 macrophage activation, and propofol-treated culture medium from M0 macrophage blocked all the effects of M0 medium on U251 cells. Additionally, DMOG reversed the effect of propofol-treated M0 medium on U251 cells. In conclusion, Propofol restricted TMZ resistance via inhibiting macrophage activation and down-regulating HIF-1α expression in GBM.

Abstract 4246: ABL103, A novel T-cell engaging bispecific antibody, exhibits potent in vitro and vivo antitumor activity and low toxicity via B7-H4 dependent 4-1BB activation in tumor microenvironment

Abstract B7-H4 (B7x, VTCN1), a member of the B7-family, is overexpressed in majority of cancer patients with ovarian, endometrial and breast cancers. B7-H4 expression was also observed in tumor associated macrophages and implicated as an immune checkpoint regulating T cell responses. Although B7-H4 expression in normal tissues is quite limited, tumor-specific immune response by ABL103 would minimize potential adverse effects. ABL103, B7-H4 Grabody-T, is a First-in Class bispecific antibody targeting B7-H4 and 4-1BB and augments T cell function by a dual mechanism, i.e., 1) blocks the B7-H4 mediated T cell inhibition, and 2) elicits superior T cell activation through B7-H4-dependent 4-1BB clustering. Our data showed that simultaneous binding of B7-H4 and 4-1BB by ABL103 led to potent in vitro T cell activation only in the presence of B7-H4 expressing tumor cells. In the established tumor model, ABL103 potently inhibited tumor progression in a dose-dependent manner and showed higher rate of complete remission (CR) at 2 and 10 mg/kg dose groups. Moreover, mice were protected from the tumor re-challenge 3 months after cessation of ABL103 treatment, suggesting long-term memory has been established. In 4-week pilot tox study using cynomolgus monkeys, ABL103 was tolerable up to 100 mg/kg dosed weekly with no ABL103-related toxicity observations. To understand the relationship of target expression, expression of B7-H4, CD4, CD8, PD-L1, and 4-1BB was examined in 142 ovarian cancer patient biopsies. About 83% of ovarian cancer patient tissues showed B7-H4 positive staining and 62% of them showed strong positive. In addition, the staining of 4-1BB as well as CD4 and CD8 T cells were observed in both tumor nest and stroma, suggesting that cross-linking of B7-H4 and 4-1BB is feasible in tumor microenvironment. Overall, ABL103 has a strong in vitro and vivo anti-tumor activity and good safety profile via B7-H4-dependent 4-1BB activation. This strongly suggests ABL103 is a promising therapeutic agent potentially benefitting patients with B7-H4 overexpression. Citation Format: Kyungjin Park, Yangsoon Lee, Saeyi Lim, Kyeongsu Park, Eunjung Kim, Hanbyul Lee, Jiseon Yoo, Youngdon Pak, Yeunju Kim, Minji Ko, Jonghwa Won. ABL103, A novel T-cell engaging bispecific antibody, exhibits potent in vitro and vivo antitumor activity and low toxicity via B7-H4 dependent 4-1BB activation in tumor microenvironment [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 4246.

Abstract 2888: Tumor-targeted CD28 bispecific POWERbody࣪ for safe and synergistic T cell-mediated immunotherapy

Abstract Targeting CD28 for systemic T cell activation caused severe cytokine storm and multiorgan failure in an anti-CD28 antibody TGN1412 phase 1 trial. However, tumor specific CD28 targeting in a tumor associated antigen (TAA)×CD28 bispecific format, similar to the clinically validated tumor specific CD3 bispecific T-cell engagers (TCEs), offers an attractive solution to mitigate the serious safety concerns associated with systemic CD28 activation while delivering potent T-cell costimulatory signal. Our goal is to combine tumor specific bispecific TCEs targeting both CD3 and CD28, the two essential pathways in T cell activation for safe and long-lasting T cell-mediated synergistic immunotherapies. Following our success in utilizing the CD3 POWERbody™ TCE platform for tumor targeting with tight safety control, we further applied our suite of antibody technologies to develop tumor specific bispecific CD28 POWERbody TCE programs. Our NEObody™ and SAFEbody® technologies enabled us to discover and engineer species cross-reactive anti-CD28 antibodies targeting a unique and conserved epitope of CD28 as well as precision masking of the antigen binding sites for conditional activation in tumor microenvironment. The engineered tailor-made anti-CD28 arm and the tumor specific antigen targeting arm were then integrated into our proprietary bispecific platform that has robust CMC properties. Toward this end we developed multiple TAA×CD28 bispecific TCEs, including B7-H3×CD28, HER2×CD28, and TROP-2×CD28, etc., which possess fine-tuned specificity and safety profiles to minimize their on-target off-tumor toxicities and to prevent the systemic cytokine release syndrome (CRS). These TAA×CD28 bispecific POWERbodies have no superagonist activities on their own and can be activated for tumor antigen binding by the TAA arm and T cell engagement by the CD28 arm. When combined with TAA×CD3 TCEs and/or checkpoint inhibitors, they show strong synergistic T cell-mediated antitumor responses with robust safety profiles. Taken together, our tumor specific CD28 bispecific POWERbody TCEs exhibit enormous potential to fulfill the promises of safe and durable T cell-mediated immunotherapies when combined with CD3 bispecific POWERbody TCEs and/or checkpoint inhibitors. Citation Format: Guizhong Liu, Zhengxi Dai, Jiagui Qu, Jianfeng Shi, Qi Zhao, Bin Cai, Aaron N. Nguyen, Songmao Zheng, Jiangchun Xu, Yan Li, Felix Du, Peter Luo. Tumor-targeted CD28 bispecific POWERbody࣪ for safe and synergistic T cell-mediated immunotherapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2888.

Phase 1 study of ADG126, a novel masked anti-CTLA-4 SAFEbody, that combines tumor-localized activation with strong Treg depletion and soft ligand blocking in patients with advanced solid tumors.

e17601 Background: SAFEbody ADG126, a masked version of NEObody ADG116 (ESMO IO Conference Abstract #394, NCT04501276), targets a unique species-conserved CTLA-4 epitope with preclinical safety and efficacy profiles superior to ipilimumab, an approved anti-CTLA-4 immune checkpoint inhibitor known to cause treatment-related irAEs in ̃70% of patients. ADG126 is designed to unlock the great potential of anti-CTLA-4 immunotherapy in 4 key ways: 1) improving safety through masking to limit on-target off-tumor irAEs in normal tissues, 2) widening the therapeutic window through selective activation in tumor microenvironment (TME), 3) maximizing anti-tumorigenic effects through prolonged exposure and steady accumulation of activated ADG126 in TME, 4) enhancing antitumor potency relative to ipilimumab via a higher Teff/Treg ratio achieved by combining T cell activation and strong ADCC-mediated Treg depletion in TME. We present interim results from our ongoing Phase 1 study of ADG126 (NCT04645069). Methods: ADG126 monotherapy [0.1, 0.3, 1, 3, 10 mg/kg (mpk)] was given to patients with advanced solid tumors Q3W IV. Primary endpoints are safety and tolerability. Secondary endpoints are PK, ORR per RECIST v1.1, and PFS. Results: For 16 patients treated in dose escalation cohorts (≤10 mpk), the median age was 65 years with 31% receiving >3 prior lines of therapies, and 31% progressed from immuno-oncology (IO) therapy. ADG126 was well-tolerated with no DLTs observed, nor was the MTD reached. Only Grade 1 TRAEs were reported, with fatigue (19%) and pruritis (13%) being most common. Plasma PK was approximately linear with a 1.7-fold increase in the mean t1/2z for the total drug over the intact ADG126, suggesting the activated ADG126 accumulated steadily with > 2 fold accumulation at Ctrough during repeat dosing, resulting in saturating target engagement at 10 mpk. Stable disease was seen in 5/16 patients with 1/5 surpassing > 24 weeks. One ovarian cancer, and 1 uveal melanoma patient who progressed on nivolumab/ipilimumab, showed > 20% durable reductions in target lesions by CT, and increased CD8+ T cells post-dosing. In the same ovarian cancer patient, a 77% reduction in CA-125 occurred after 7 treatment cycles at 1 mpk. Conclusions: ADG126 demonstrated excellent tolerability and safety for continuous dosing beyond 4 cycles at 10 mpk and for more than 8 cycles at 1 mpk. Compared to ADG116, its non-masked parental Ab, ADG126 exhibited superior PK and early efficacy signals correlated with increased peripheral CD8+ T cells, in general. ADG126 may offer better safety and efficacy profile than ipilimumab, which could help realize the full potential of blocking the CTLA-4 pathway. Combination studies of ADG126 with anti-PD-1Ab(s) have been initiated to determine their safety and efficacy in IO-sensitive and resistant cancer types. Clinical trial information: NCT04645069.

Ferroptosis-related local immune cytolytic activity in tumor microenvironment of basal cell and squamous cell carcinoma.

Background: Ferroptosis, a recently discovered form of cell death, whose role in basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) has not been well disclosed. To improve our understanding of the differences in tumor progression and therapeutic effects between BCC and SCC, and to find potential therapeutic targets, this study systematically analyzed ferroptosis-related genes (FRGs) and their associated local immune cytolytic activity (LICA) and tumor microenvironment (TME) metabolic function differences.Methods: Two bulk RNA-seq datasets, GSE7553 and GSE125285, from the Gene Expression Omnibus database were compared within and between groups to screen for common differentially expressed genes (DEGs) for enrichment analysis. The currently recognized FRGs in DEGs gene set were selected as the targets to analyze their correlation and difference in LICA and TME metabolic functions. And validated using immune cell populations from another single-cell RNA-seq (scRNA-seq) dataset (GSE123813) to accurately understand the difference in LICA. All of the gene sets for functional enrichment analysis comes from published results and MSigDB database.Results: Ten FRGs were used to further analyze the differences in LICA and TME metabolic functions between BCC and SCC. In the SCC samples, LICA (e.g. Treg, CCR, Cytolytic activity, etc.) and TME metabolic functions (e.g. lipid and energy, etc.) were significantly related to ferroptosis genes (e.g. SLC1A5, CD44, NQO1, HMOX1 and STEAP3), and the ferroptosis potential index were also significantly higher than that in the BCC samples. Finally, based on these ten FRGs and related enrichment results, we postulated a model of NQO1 homeostasis regulated by FRGs during induction of ferroptosis in SCC.Conclusions: The results showed that three FRGs, SLC1A5, CD44 and NQO1, have significant potential in targeted therapies for SCC chemotherapy resistance. And two FRGs, STEAP3 and HMOX1, formed a synergistic effect on the occurrence of ferroptosis in tumor cells. Our findings can be used as the main research materials for metastasis and chemotherapy resistance in SCC patients.

Abstract LBA009: Orally available ENPP1 inhibitor, TXN10128, restores STING activation in tumor microenvironment and confers anti-tumor responses in combination with immune checkpoint blockade

Abstract Background Recently, there are growing needs of immune modulators that can convert cold tumors into hot tumors, which can be utilized for combination treatment with existing immune related therapies. An orally available small molecule that is capable of activating innate immune response can be an ideal candidate to meet those needs. Upon binding to 2’3’-cGAMP, STING activates TBK1-IRF3 signaling cascade in cancer cells as well as host cells and promotes innate immune responses against cancer cells, leading to T cell mediated anti-tumor immunity by facilitating T cell priming and infiltration. Ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1), a transmembrane protein highly expressed in subset of cancer cells, has been known to hydrolyze 2’3’-cGAMP and negatively regulates the STING activation. Inhibition of ENPP1 can prevent 2’3’-cGAMP degradation in tumor microenvironment (TME) and restore STING activation, leading to innate immune responses. It has been shown that ENPP1 inhibitor can enhance anti-tumor immunity by restoring 2’3’-cGAMP level in TME and can prevent tumor growth when co-treated with immune checkpoint blockade (ICB) as well as with radiation therapy. Methods The activity of ENPP1 inhibitors were measured in enzymatic assay using 2’3’-cGAMP as substrate and in cellular STING activation assay using IRF3-responsive reporter. Also, the effects on innate immune response were estimated in LIN (Lymphocyte INfiltration) assay measuring lymphocyte infiltration and TMED (TME in Dish) assay measuring tumor spheroid growth and immune cell activation. In vivo efficacy of TXN10128 (PO dosing) was evaluated in MC38 syngeneic model in combination with and anti-PD-L1 (IV dosing). Tumor growth was monitored and immune cells in tumor were analyzed. Results TXN10128 inhibited ENPP1 activity with single digit nanomolar potency in enzyme assay and further induced STING activation in cellular assay. In 3D spheroid co-culture condition, TXN10128 enhances lymphocyte infiltration and inhibits the spheroid growth. TXN10128 has a drug-like properties desirable for oral administration in terms of physicochemical properties and pharmacokinetics parameters. Systemic exposure of TXN10128 by PO dosing resulted in synergistic tumor growth inhibition with anti-PD-L1 antibody and improved tumor-infiltrating lymphocytes (TIL) profile as expected in MC38 syngeneic model. Additional in vivo studies are on-going to expand applicable cancer types to TXN10128 treatment. Conclusions TXN10128 is a potent and selective ENPP1 inhibitor that can exert immune response in 3D co-culture condition, which is consistent with tumor growth inhibition and favorable TIL profile in animal model. Together with promising drug-likeness, these studies demonstrate that TXN10128 is a suitable candidate for clinical investigation as a combination partner with existing immunotherapies. Citation Format: Sungjoon Kim, Imran Ali, Ahran Yu, Sun woo Lee, Sung young Park, Jung hwan Choi, Yong-yea Park, Chan sun Park. Orally available ENPP1 inhibitor, TXN10128, restores STING activation in tumor microenvironment and confers anti-tumor responses in combination with immune checkpoint blockade [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2021 Oct 7-10. Philadelphia (PA): AACR; Mol Cancer Ther 2021;20(12 Suppl):Abstract nr LBA009.

Smart Nanozyme Platform with Activity‐Correlated Ratiometric Molecular Imaging for Predicting Therapeutic Effects

AbstractNanozymes with intrinsic enzyme‐like characteristics have attracted enormous research interest in biological application. However, there is a lack of facile approach for evaluating the catalytic activity of nanozymes in living system. Herein, we develop a novel manganese‐semiconducting polymer‐based nanozyme (MSPN) with oxidase‐like activity for reporting the catalytic activity of itself in acid‐induced cancer therapy via ratiometric near‐infrared fluorescence (NIRF)‐photoacoustic (PA) molecular imaging. Notably, MSPN possess oxidase‐like activity in tumor microenvironment, owing to the mixed‐valent MnOx nanoparticles, which can effectively kill cancer cells. Because the semiconducting polymer (PFODBT) is conjugated with oxidase‐responsive molecule (ORM), the catalytic activity of nanozyme can be correlated with the ratiometric signals of NIRF (FL695/FL825) and PA (PA680/PA780), which may provide new ideas for predicting anticancer efficacy of nanozymes in living system.

Smart Nanozyme Platform with Activity-Correlated Ratiometric Molecular Imaging for Predicting Therapeutic Effects.

Nanozymes with intrinsic enzyme-like characteristics have attracted enormous research interest in biological application. However, there is a lack of facile approach for evaluating the catalytic activity of nanozymes in living system. Herein, we develop a novel manganese-semiconducting polymer-based nanozyme (MSPN) with oxidase-like activity for reporting the catalytic activity of itself in acid-induced cancer therapy via ratiometric near-infrared fluorescence (NIRF)-photoacoustic (PA) molecular imaging. Notably, MSPN possess oxidase-like activity in tumor microenvironment, owing to the mixed-valent MnOx nanoparticles, which can effectively kill cancer cells. Because the semiconducting polymer (PFODBT) is conjugated with oxidase-responsive molecule (ORM), the catalytic activity of nanozyme can be correlated with the ratiometric signals of NIRF (FL695 /FL825 ) and PA (PA680 /PA780 ), which may provide new ideas for predicting anticancer efficacy of nanozymes in living system.