Acidity-targeting transition-aided universal chimeric antigen receptor T-cell (ATT-CAR-T) therapy for the treatment of solid tumors.

The use of CAR-T cells in treating solid tumors frequently faces significant challenges, mainly due to the heterogeneity of tumor antigens. This study assessed the efficacy of an acidity-targeting transition-aided universal chimeric antigen receptor T (ATT-CAR-T) cell strategy, which is facilitated by an acidity-targeted transition. Specifically, the EGFRvIII peptide was attached to the N-terminus of a pH-low insertion peptide. Triggered by the acidic conditions of the tumor microenvironment, this peptide alters its structure and selectively integrates into the membrane of solid tumor cells. The acidity-targeted transition component effectively relocated the EGFRvIII peptide across various tumor cell membranes; thus, allowing the direct destruction of these cells by EGFRvIII-specific CAR-T cells. This method was efficient even when endogenous antigens were absent. In vivo tests showed marked antigen modification within the acidic tumor microenvironment using this component. Integrating this component with CAR-T cell therapy showed high effectiveness in combating solid tumors. These results highlight the capability of ATT-CAR-T cell therapy to address the challenges presented by tumor heterogeneity and expand the utility of CAR-T cell therapy in the treatment of solid tumors.

Potent antitumor activity of a bispecific T-cell engager antibody targeting the intracellular antigen KRAS G12V.

Kirsten Rat Sarcoma viral oncogene homolog (KRAS) is one of the most frequent oncogenes. However, there are limited treatment options due to its intracellular expression. To address this, we developed a novel bispecific T-cell engager (BiTE) antibody targeting HLA-A2/KRAS G12V complex and CD3 (HLA-G12V/CD3 BiTE). We examined its specific binding to tumor cells and T cells, as well as its anti-tumor effects in vivo. HLA-G12V/CD3 BiTE was expressed in Escherichia coli and its binding affinities to CD3 and HLA-A2/KRAS G12V were measured by flow cytometry, along with T-cell activation. In a xenograft pancreatic tumor model, the HLA-G12V/CD3 BiTE's anti-tumor effects were assessed through tumor growth, survival time, and safety. Our results demonstrated specific binding of HLA-G12V/CD3 BiTE to tumor cells with an HLA-A2/KRAS G12V mutation and T cells. The HLA-G12V/CD3 BiTE also activated T-cells in the presence of tumor cells in vitro. HLA-G12V/CD3 BiTE in vivo testing showed delayed tumor growth without severe toxicity to major organs and prolonged mouse survival. This study highlights the potential of constructing BiTEs recognizing an HLA-peptide complex and providing a novel therapy for cancer treatment targeting the intracellular tumor antigen.

Efficacy and safety of second-line therapy by S-1 combined with sintilimab and anlotinib in pancreatic cancer patients with liver metastasis: a single-arm, phase II clinical trial.

Background: Pancreatic adenocarcinoma carries a grim prognosis, and there are few recognized effective second-line treatment strategies. We attempted to evaluate the efficacy and safety of a combination of S-1, sintilimab, and anlotinib as a second-line treatment in pancreatic cancer patients with liver metastasis. Methods: Pancreatic cancer patients with liver metastases were recruited. S-1 was administered orally at 25 mg/m2 bid, anlotinib was administered orally at 12 mg qd from day 1 to day 14, and sintilimab was administered intravenously at 200 mg on day 1. This method was repeated every 21 days, and the therapeutic effect was evaluated every 3 cycles. The primary outcome was the objective response rate (ORR). Results: Overall, 23 patients were enrolled in this study of whom 19 patients had objective efficacy evaluation. The ORR was 10.5% (95% CI 0.4%-25.7%) in the evaluable population. The progression-free survival (PFS) was 3.53 (95% CI 2.50-7.50) months, and the overall survival (mOS) was 8.53 (95% CI 4.97-14.20) months. Grade 3 adverse events were 26.1%, and no grade 4 or above adverse events occurred. High-throughput sequencing was performed on the tumor tissues of 16 patients; patients with HRD-H (n = 10) had shorter PFS than those with HRD-L (n = 6) (2.43 vs. 5.45 months; P = 0.043), but there was no significant difference in OS between the two groups (4.43 vs. 9.35 months; P = 0.11). Conclusions: This study suggests the advantage of S-1 combined with sintilimab and anlotinib in extending OS as a second-line therapy in pancreatic cancer patients with liver metastasis. Clinical Trial Registration: ChiCTR2000030659.

Membrane fusogenic nanoparticle-based HLA-peptide-addressing universal T cell receptor-engineered T (HAUL TCR-T) cell therapy in solid tumor.

T cell receptor-engineered T (TCR-T) cell therapy has demonstrated therapeutic effects in basic research and clinical trials for treating solid tumors. Due to the peptide-dependent recognition and the human leukocyte antigen (HLA)-restriction, TCR-T cell therapy is generally custom designed to target individual antigens. The lack of suitable universal targets for tumor cells significantly limits its clinical applications. Establishing a universal TCR-T treatment strategy is of great significance. This study designed and evaluated the HLA-peptide-addressing universal (HAUL) TCR-T cell therapy based on HLA-peptide (pHLA) loaded membrance fusogenic deliver system. The pHLA-NP-based tumor cell membrane modification technology can transfer the pHLA onto the surface of tumor cells through membrane fusogenic nanoparticles. Then tumor cells are recognized and killed by TCR-T cells specifically. The HAUL TCR-T cell therapy technology is a universal technology that enables tumor cells to be identified and killed by specific TCR-T cells, regardless of the HLA typing of tumor cells.

Coix seed oil alleviates synovial angiogenesis through suppressing HIF-1α/VEGF-A signaling pathways via SIRT1 in collagen-induced arthritis rats.

BACKGROUND: Rheumatoid arthritis (RA) is a chronic autoimmune disorder characterized by symmetric arthritis. Coix Seed Oil (CSO) has been shown to reduce inflammation in collagen induced arthritis (CIA) rats. However, the effect of CSO on synovial angiogenesis in RA is unknown. In this study, we aimed to explore whether CSO could inhibit RA synovial angiogenesis and elucidate the underlying mechanisms. METHODS: CIA rat models were established and subjected to different doses of CSO treatments for four weeks in vivo. Arthritis index, paw swelling, and weight were recorded to assess clinical symptoms. Hematoxylin and Eosin staining, Safarnin O fast green staining, Micro-CT, Immunohistochemical, and Immunofluorescence (IF) staining were performed to examined changes in synovial and joint tissues. The serum HIF-1α and VEGF-A levels were evaluated through enzyme-linked immunosorbent assay. Fibroblast-like synoviocytes (FLS) of rats was stimulated with tumor necrosis factor-α (TNF-α) for developing inflammatory model in vitro. Optimal concentrations of CSO and TNF-α for stimulation were measured through Cell Counting Kit-8 test. Wound healing and Transwell migration experiments were employed to determine FLS migratory ability. IF staining was performed to assess HIF-1α nuclear translocation in FLS. Protein levels of SIRT1, HIF-1α, VEGF-A, and CD31 were assessed through Western blot. The isolated aortic rings were induced with recombinant rat VEGF-A 165 (VEGF-A165) to observe the CSO inhibitory impact on angiogenesis ex vivo. RESULTS: CSO attenuated the progression of arthritis in CIA rats, mitigated histopathological deterioration in synovial and joint tissues, significantly inhibited immature vessels labeled with CD31+/αSMA-, and reduced the micro-vessels in VEGF-A165 induced aortic rings. Moreover, it upregulated SIRT1 protein levels in CIA rats and TNF-α induced FLS, but decreased HIF-1α and VEGF-A protein levels. Furthermore, CSO inhibited the migration ability and HIF-1α nuclear translocation of TNF-α induced FLS. Finally, suppressing SIRT1 levels in TNF-α induced FLS enhanced their migration ability, HIF-1α nuclear translocation, and the protein levels of HIF-1α, VEGF-A, and CD31, whereas the inhibitory effect of CSO on TNF-α induced FLS was severely constrained. CONCLUSIONS: This study indicates that CSO can alleviate synovial angiogenesis through suppressing HIF-1α/VEGF-A signaling pathways via SIRT1 in CIA rats.

Enhanced systemic tumor suppression by in situ vaccine combining radiation and OX40 agonist with CpG therapy.

BACKGROUND: In situ tumor vaccine has been gradually becoming a hot research field for its advantage of achieving personalized tumor therapy without prior antigen identification. Various in situ tumor vaccine regimens have been reported to exert considerable antitumor efficacy in preclinical and clinical studies. However, the design of in situ tumor vaccines still needs further optimization and the underlying immune mechanism also waits for deeper investigation. METHODS: A novel triple in situ vaccine strategy that combining local radiation with intratumoral injection of TLR9 agonist CpG and OX40 agonist was established in this sturdy. Local and abscopal antitumor efficacy as well as survival benefit were evaluated in the bilateral tumors and pulmonary metastasis model of B16F10 melanoma. In situ vaccine-induced immune responses and immune-associated variation in tumor environment were further investigated using multiparameter flow cytometry and RNA sequencing. Base on the analysis, the RT + CpG + αOX40 triple in situ vaccine was combined with checkpoint blockade therapy to explore the potential synergistic antitumor efficacy. RESULTS: Enhanced tumor suppression was observed with minimal toxicity in both treated and untreated abscopal tumors after receiving RT + CpG + αOX40 triple vaccine. The introduction of local radiation and OX40 agonist benefit more to the inhibition of local and abscopal lesions respectively, which might be partially attributed to the increase of effector memory T cells in the tumor microenvironment. Further analysis implied that the triple in situ vaccine did not only activate the microenvironment of treated tumors, with the upregulation of multiple immune-associated pathways, but also enhanced systemic antitumor responses, thus achieved superior systemic tumor control and survival benefit. Moreover, the triple in situ vaccine synergized with checkpoint blockade therapy, and significantly improved the therapeutic effect of anti-programmed cell death protein (PD)-1 antibody. CONCLUSION: This triple combining in situ vaccine induced intensive antitumor responses, mediated effective systemic tumor control and survival benefit, and displayed impressive synergistic antitumor effect with checkpoint blockade therapy. These data preliminary confirmed the efficacy, feasibility and safety of the triple combining in situ vaccine, suggesting its great application potential as both monotherapy and a part of combined immunotherapeutic regimens in clinical scenario.

Self-assembled nanoparticles: A new platform for revolutionizing therapeutic cancer vaccines.

Cancer vaccines have had some success in the past decade. Based on in-depth analysis of tumor antigen genomics, many therapeutic vaccines have already entered clinical trials for multiple cancers, including melanoma, lung cancer, and head and neck squamous cell carcinoma, which have demonstrated impressive tumor immunogenicity and antitumor activity. Recently, vaccines based on self-assembled nanoparticles are being actively developed as cancer treatment, and their feasibility has been confirmed in both mice and humans. In this review, we summarize recent therapeutic cancer vaccines based on self-assembled nanoparticles. We describe the basic ingredients for self-assembled nanoparticles, and how they enhance vaccine immunogenicity. We also discuss the novel design method for self-assembled nanoparticles that pose as a promising delivery platform for cancer vaccines, and the potential in combination with multiple therapeutic approaches.

Nanomodified Switch Induced Precise and Moderate Activation of CAR-T Cells for Solid Tumors.

Chimeric antigen receptor (CAR)-T cell therapy is a transformative treatment against advanced malignancies. Unfortunately, once administrated in vivo, CAR-T cells become out of artificial control, and fierce response to CAR-T therapy may cause severe adverse events, represented by cytokine-release syndrome and on-target/off-tumor effects. Here, a nanomodified switch strategy is developed, leading to sustained and precise "on-tumor only" activation of CAR-T cells. Here, original gelatinase-responsive nanoparticles (NPs) are used to selectively deliver the heterodimerizing switch, which is the key component of switchable CAR with separated activation modules. The "NanoSwitch" is tumor-specific, thus inactivated switchable CAR-T cells do little harm to normal cells, even if the normal cells express the target of CAR-T. Owing to the sustained-release effect of NPs, the CAR-T cells are activated smoothly, avoiding sudden release of cytokine. These data introduce NanoSwitch as a universal and applicable solution to safety problems of CAR-T therapy regardless of the target.

Biomarkers for predicting tumor response to PD-1 inhibitors in patients with advanced pancreatic cancer.

Pancreatic cancer is among the most lethal malignant neoplasms, and few patients with pancreatic cancer benefit from immunotherapy. We retrospectively analyzed advanced pancreatic cancer patients who received PD-1 inhibitor-based combination therapies during 2019-2021 in our institution. The clinical characteristics and peripheral blood inflammatory markers (neutrophil-to-lymphocyte ratio [NLR], platelet-to-lymphocyte ratio [PLR], lymphocyte-to-monocyte ratio [LMR], and lactate dehydrogenase [LDH]) were collected at baseline. Chi-squared and Fisher's exact tests were used to evaluate relationships between the above parameters and tumor response. Cox regression analyses were employed to assess the effects of baseline factors on patients' survival and immune-related adverse events (irAEs). Overall, 67 patients who received at least two cycles of PD-1 inhibitor were considered evaluable. A lower NLR was independent predictor for objective response rate (38.1% vs. 15.2%, P = .037) and disease control rate (81.0% vs. 52.2%, P = .032). In our study population, patients with lower LDH had superior progression-free survival (PFS) and overall survival(OS) (mPFS, 5.4 vs. 2.8 months, P < .001; mOS, 13.3 vs. 3.6 months, P < .001). Liver metastasis was verified to be a negative prognostic factor for PFS (2.4 vs. 7.8 months, P < .001) and OS (5.7 vs. 18.0 months, P < .001). The most common irAEs were hypothyroidism (13.4%) and rash (10.5%). Our study demonstrated that the pretreatment inflammatory markers were independent predictors for tumor response, and the baseline LDH level and liver metastasis were potential prognostic markers of survival in patients with pancreatic cancer treated with PD-1 inhibitors.

Engineered Lactococcus lactis secreting Flt3L and OX40 ligand for in situ vaccination-based cancer immunotherapy.

In situ vaccination is a promising strategy to convert the immunosuppressive tumor microenvironment into an immunostimulatory one with limited systemic exposure and side effect. However, sustained clinical benefits require long-term and multidimensional immune activation including innate and adaptive immunity. Here, we develop a probiotic food-grade Lactococcus lactis-based in situ vaccination (FOLactis) expressing a fusion protein of Fms-like tyrosine kinase 3 ligand and co-stimulator OX40 ligand. Intratumoural delivery of FOLactis contributes to local retention and sustained release of therapeutics to thoroughly modulate key components of the antitumour immune response, such as activation of natural killer cells, cytotoxic T lymphocytes, and conventional-type-1-dendritic cells in the tumors and tumor-draining lymph nodes. In addition, intratumoural administration of FOLactis induces a more robust tumor antigen-specific immune response and superior systemic antitumour efficacy in multiple poorly immune cell-infiltrated and anti-PD1-resistant tumors. Specific depletion of different immune cells reveals that CD8+ T and natural killer cells are crucial to the in situ vaccine-elicited tumor regression. Our results confirm that FOLactis displays an enhanced antitumour immunity and successfully converts the 'cold' tumors to 'hot' tumors.

Engineering a HemoMap Nanovaccine for Inducing Immune Responses against Melanoma.

Neoantigen vaccines have opened a new paradigm for cancer immunotherapy. Here, we constructed a neoantigen nanovaccine-HemoMap, with the ability to target lymph nodes and activate immune cells. We propose a HemoMap nanovaccine consisting of the mouse melanoma highly expressed antigenic peptide Tyrp1 and a magnesium nanoadjuvant-HemoM. By immunofluorescence labeling of the nanovaccine, the lymph node targeting of the vaccine was observed and verified by a mouse near-infrared imaging system. About two-fold higher effective retention of HemoMap induces the internalization of Tyrp1 in DCs than that of free Tyrp1 in draining lymph nodes (DLNs) for 48 h. A mouse melanoma subcutaneous model was established to evaluate neoantigen-specific antitumor immune responses. In comparison to the control group, the tumor growth rate was dramatically slowed down by HemoMap treatment, and the median survival time was extended by 7 days. We discovered that effective co-delivery of Tyrp1 antigen and magnesium (Mg2+) to lymph nodes (LNs) boosted cellular internalization and activated immune cells, such as CD11c+ DCs and CD8+ T lymphocytes. Spleen lymphocytes from the HemoMap group displayed much more antitumor activity than those from the other groups. Our findings highlight that HemoMap is promising to trigger T cell responses and to provide novel nanoadjuvants strategies for cancer immunotherapy.

Modification of erythrocytes by internalizing Arg-Gly-Asp (iRGD) in boosting the curative effect of radiotherapy for gastric carcinoma.

Background: Radiation resistance remains the leading cause of radiotherapy (RT) failure. The development of tumor-specific targeted sensitizers is key to overcoming radiation resistance. Our early data showed that cancer cell penetration was simulated by internalizing arginine-glycine-aspartic acid (iRGD), and the irradiation efficacy was improved. The present study aims to design and fabricate iRGD-modified red blood cell (RBCs) for tumor targeting and RT enhancement, and to evaluate its safety and efficacy in vivo. Methods: 1,2-Distearoyl-sn-glycero-3-phosphoethanolamine-poly ethylene glycol-iRGD (DSPE-PEG-iRGD) was used to modify RBCs by a lipid-insertion method without direct chemical bioconjugation. Fluorescent dyes were used to trace the functional RBCs through confocal microscopy examination. In vitro stability evaluation was performed using cell culture medium incubation for 48 h followed by fluorescence decay assay. Furthermore, a subcutaneous cancer cell mouse model was constructed with MKN-45 cells for target efficacy and RT enhancement evaluation with DSPE-PEG-iRGD-modified RBCs (RBC-iRGD). Results: Successful construction of RBC-iRGD was verified by the presence of the yellow fluorescence, and an approximately 108 iRGD molecules were labeled on a single RBC. The final RBC-iRGD showed good stability without any hemolytic effects in the cell culture medium. Moreover, higher fluorescence intensity and decreased liver and spleen accumulation could be observed in RBC-iRGD compared to RBC + iRGD in vivo. The RBC-iRGD exerted enhanced radiosensitivity in subcutaneous gastric tumor mice. Conclusions: The RBC-iRGD exerted good tumor-targeting efficacy and favorable effects for RT enhancement in vivo.

Isolation, Identification, and Genetic Phylogenetic Analysis of Two Different Genotypes of Bovine Parainfluenza 3 Virus in China.

Bovine parainfluenza virus 3 (BPIV3) is one of several viruses that contribute to bovine respiratory disease complex (BRDC). During this study, isolation of BPIV3 was attempted from 20 PCR-positive swabs by Madin-Darby Bovine Kidney (MDBK) cells. Nine samples showed obvious cytopathic lesions identified as BPIV3 by reverse-transcription polymerase chain reaction amplification and sequencing. The genomes of isolates XJ21032-1 and XJ20055-3 were sequenced using Illumina sequencing technology and determined to have lengths of 15,512 bp and 15,479 bp, respectively. Phylogenetic analysis revealed that isolate XJ21032-1 was genotype B, and isolate XJ20055-3 was genotype C. In addition, the two isolates had multiple amino acid changes in nucleocapsid protein, fusion protein, and hemagglutinin/neuraminidase, major antigenic proteins. This allows the further recognition of the presence of BPIV3 type B in Chinese cattle herds. We hope this will help trace the origin of BPIV3, improve the understanding of differences between genotypes, and provide data support for vaccine development.

Study protocol for a prospective, open-label, single-arm, phase II study on the combination of tislelizumab, nab-paclitaxel, gemcitabine, and concurrent radiotherapy as the induction therapy for patients with locally advanced and borderline resectable pancreatic cancer.

Background: Pancreatic ductal adenocarcinoma (PDAC) is a fatal malignancy with a low resection rate. Chemotherapy and radiotherapy (RT) are the main treatment approaches for patients with advanced pancreatic cancer, and neoadjuvant chemoradiotherapy is considered a promising strategy to increase the resection rate. Recently, immune checkpoint inhibitor (ICI) therapy has shown remarkable efficacy in several cancers. Therefore, the combination of ICI, chemotherapy, and concurrent radiotherapy is promising for patients with potentially resectable pancreatic cancer, mainly referring to locally advanced (LAPC) and borderline resectable pancreatic cancer (BRPC), to increase the chances of conversion to surgical resectability and prolong survival. This study aims to introduce the design of a clinical trial. Methods: This is an open-label, single-arm, and single-center phase II trial. Patients with pathologically and radiographically confirmed LAPC or BRPC without prior anti-cancer treatment or severe morbidities will be enrolled. All patients will receive induction therapy and will be further evaluated by the Multiple Disciplinary Team (MDT) for the possibility of surgery. The induction therapy consists of up to four cycles of gemcitabine 1,000 mg/m2 and nab-paclitaxel 125 mg/m2 via intravenous (IV) infusion on days 1 and 8, along with tislelizumab (a PD-1 monoclonal antibody) 200 mg administered through IV infusion on day 1 every 3 weeks, concurrently with stereotactic body radiation therapy (SBRT) during the third cycle of treatment. After surgery, patients without progression will receive another two to four cycles of adjuvant therapy with gemcitabine, nab-paclitaxel, and tislelizumab. The primary objectives are objective response rate (ORR) and the R0 resection rate. The secondary objectives are median overall survival (mOS), median progression free survival (mPFS), disease control rate (DCR), pathological grade of tumor tissue after therapy, and adverse reactions. Besides, we expect to explore the value of circulating tumor DNA (ctDNA) in predicting tumor response to induction therapy and survival outcome of patients. Discussion: This is a protocol for a clinical trial that attempts to evaluate the safety and efficacy of the combination of anti-PD-1 antibody plus chemotherapy and radiotherapy as the induction therapy for LAPC and BRPC. The results of this phase II study will provide evidence for the clinical practice of this modality. Clinical Trial Registration: http://www.chictr.org.cn/edit.aspx?pid=53720&htm=4, identifier ChiCTR2000032955.

Structure stabilization effect of vacancies and entropy in hexagonal WN.

The structural stability of hexagonal tungsten mononitride (WN) has been studied combining scanning transmission electron microscopy and first-principles calculations. The results show that the WC-type WN with vacancies of 6∼8 at% is more stable than the previously proposed MnP-type and NiAs-type structures. Due to the larger vibrational entropy of the WC-type WN, the vacancy concentration required to stabilize the WC-type structure is lower at high temperatures. The results demonstrate the importance of vacancies and configurational and vibrational entropies in the structural stability of compounds synthesized at high temperatures.

Neoantigen-targeted TCR-T cell therapy for solid tumors: How far from clinical application.

T cell receptor-engineered T (TCR-T) cells targeting neoantigens present potential immunotherapy for solid tumors. With the continuous optimization of the entire production procedures, the manufacturing process of TCR-T cells is becoming more efficient and productive. However, clinical-scale manufacturing of TCR-T cells still encounters tremendous challenges. Here, we summarize the latest progress of neoantigen-targeted TCR-T cell therapy and focus on the technical difficulties in preparing personalized neoantigen-targeted TCR-T cells and the challenges in clinical applications. Possible approaches for improving TCR-T cell therapy are discussed as well in this review.

In situ gelatinase-responsive and thermosensitive nanocomplex for local therapy of gastric cancer with peritoneal metastasis.

Intraperitoneal chemotherapy (IPC) has been considered as an effective therapy for advanced gastric cancer (GC) especially those with peritoneal metastasis, while limited effectiveness, complications caused by chemotherapeutics and repeated infusion procedures restrict the application of IPC. In this study, to enhance the efficacy and safety of IPC, we intended to establish a biocompatible and biodegradable nanocomplex composed of intelligent gelatinase-responsive nanoparticles (NPs) and thermosensitive gel, which were prepared from different compositions of poly (ethyleneglycol)-poly (3-caprolactone) (PEG-PCL). Cancer stem cells (CSCs) inhibitor Salinomycin (SAL) and non-CSC inhibitor Docetaxel (DOC) were co-loaded in the NPs and delivered by liquid PEG-PCL-PEG gel (PECE) at room temperature, which was able to target tumor and formed a gel in situ at body temperature. Compared with free SAL-DOC solution administered at the same dose, PECE NP group inhibited intraperitoneal disseminated gastric cancer growth more remarkably, some of which even achieved complete response (CR) and continued for more than 2 weeks. Cytometric analysis of cellular suspension from abdominal tumor tissues showed that the proportion of CSCs (CD44+CD133+) and the expression of PD-L1 on the tumor cells in the PECE NP group were the lowest. In the allograft mouse models of GC, PECE NP significantly improved the infiltration of M1 macrophages into the tumor bed in vivo. This design may provide biodegradable smart drug-delivery system for potential application in IPC.

Case Report: Pathologic Complete Response to Induction Therapy in a Patient With Potentially Resectable Pancreatic Cancer.

Immune monotherapy does not appear to work in patients with pancreatic cancer so far. We are conducting a clinical trial that combines programmed cell death protein-1 (PD-1) inhibitor with chemotherapy and concurrent radiotherapy as induction therapy for patients with locally advanced pancreatic cancer (LAPC) and borderline resectable pancreatic cancer (BRPC). Here, we report a case with a pathologic complete response (pCR) and no postoperative complications after the induction therapy. The patient received four cycles of induction therapy and achieved a partial response (PR) with a significant decline of tumor marker carbohydrate antigen 19-9 (CA19-9). Also, peripheral blood samples were collected during the treatment to investigate serial circulating tumor DNA (ctDNA) dynamic changes in predicting the tumor response and outcomes in patients. Our result suggested that PD-1 blockade plus chemotherapy and concurrent radiotherapy is a promising mode as induction therapy for patients with potentially resectable pancreatic cancer. In this case, serial ctDNA alterations accurately provide a comprehensive outlook of the tumor status and monitor the response to the therapy, as validated by standard imaging.

In situ antigen modification-based target-redirected universal chimeric antigen receptor T (TRUE CAR-T) cell therapy in solid tumors.

BACKGROUND: Chimeric antigen receptor (CAR)-T cell therapy has demonstrated remarkable success in the treatment of hematologic malignancies, while the success has not yet been replicated in solid tumors. To some extent, the disappointing results can be attributed to the paucity and heterogeneity of target antigens in solid tumors since adequate antigens are the cornerstone for CAR-T cells to recognize and attack tumor cells. METHODS: We established a target-redirected universal CAR-T (TRUE CAR-T) cell therapeutic modality, in which exogenous antigens are loaded onto fusogenic nanoparticles to achieve in situ modification of cell membrane in solid tumors, providing targets for subsequent CAR-T cell therapy. The modification effect was evaluated by flow cytometry and confocal microscopic imaging. The in vivo metabolism and biodistribution of fusogenic antigen loaded nanoparticles (F-AgNPs) was explored using near infrared living imaging. Then F-AgNPs mediated in situ antigen modification were cooperated with corresponding CAR-T cell therapy, and its antitumor efficacy was evaluated using immune function experiments and further investigated in different tumor models. RESULTS: Using F-AgNPs, exogenous antigens were selectively modified onto tumor cell membranes through membrane fusion, spread deeper into tumor tissues through intercellular lipid transfer, further activating corresponding CAR-T cells and mediating antitumor immune responses towards multiple types of tumor cells, despite of their inherent antigen profiles. The cooperative treatment of F-AgNPs and CAR-T cell therapy successfully suppressed tumor proliferation and prolonged survival in both subcutaneous and peritoneally disseminated tumor models. CONCLUSION: The fusogenic nanoparticle-based in situ antigen modification overcome the limitation of target antigens paucity and heterogeneity in solid tumors, improving the efficacy and broadening the applications of CAR-T cells, thus establishing a novel TRUE CAR-T cell therapeutic modality with universal application and translational potential in immunotherapies for solid tumors.

Tumor-penetrating peptide internalizing RGD enhances radiotherapy efficacy through reducing tumor hypoxia.

Resistance to irradiation (IR) remains a major therapeutic challenge in tumor radiotherapy. The development of novel tumor-specific radiosensitizers is crucial for effective radiotherapy against solid tumors. Here, we revealed that remodeling tumor tissue penetration via tumor-penetrating peptide internalizing arginine-glycine-aspartic acid RGD (iRGD) enhanced irradiation efficacy. The growth of 4T1 and CT26 multicellular tumor spheroids (MCTS) and tumors was delayed significantly by the treatment with IR and iRGD. Mechanistically, iRGD reduced hypoxia in MCTS and tumors, resulting in enhanced apoptosis after MCTS and tumors were treated with IR and iRGD. This is the first report that shows enhanced radiation efficacy by remodeling tumor-specific tissue penetration with iRGD, implying the potential clinical application of peptides in future tumor therapy.