Tumor-killing Effect Research Articles

Platycodin D reduces PD-L1 levels by inhibiting LXR-β activity and combines with nintedanib to enhance the tumor-killing effect of Tcells.

Most tumors are resistant to programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) checkpoint inhibitors, which may be due to impaired antigen presentation resulting from the downregulation of major histocompatibility complex class I (MHC-I) expression on tumor cells. We observed that platycodin D (PD), polygalacin D, and platycodin D2, which are plant-derived triterpenoid saponins, significantly reduced PD-L1 levels. RNA sequencing and the PharmMapper database analysis identified liver X receptor β (LXR-β) as a potential PD target. Further studies showed that PD reduces PD-L1 levels by binding to LXR-β and inhibiting LXR-β activity. Coadministration of PD and nintedanib, known to upregulate MHC-I expression, enhanced tumor recognition and killing by Tcells. This study provides new insights into PD applications and mechanisms.

The Chemo-Immunotherapeutic Roles of Tumor-Derived Extracellular Vesicle-Based Paclitaxel Delivery System in Hepatocarcinoma.

As a first-line chemotherapeutic agent, albumin-bound paclitaxel (PA) has a considerable effect on the treatment of various cancers. However, in chemotherapy for hepatocarcinoma, the sensitivity to PA is low owing to the innate resistance of hepatocarcinoma cells; the toxicity and side effects are severe, and the clinical treatment impact is poor. In this study, we present a unique nanodrug delivery system. The ultraviolet (UV)-induced tumor-cell-derived extracellular vesicles (EVs) were isolated and purified by differential centrifugation. Then, PA was loaded by coextrusion to create a vesicle drug delivery system (EVPA). By employing the EV-dependent enhanced retention effect and specific homing effect, EVPA would passively and actively target tumor tissues, activate the immune response to release PA, and achieve the combination therapeutic effect of chemo-immunotherapy on hepatocarcinoma. We demonstrated that the tumor-killing effect of EVPA is superior to that of PA, both in vivo and in vitro and that EVPA can be effectively taken up by hepatocarcinoma and dendritic cells, activate the body's specific immune response, promote the infiltration of CD4+ and CD8+ T cells in tumor tissues, and exert a precise killing effect on hepatocarcinoma cells via chemo-immunotherapy.

Synergizing Immunotherapy and Antibody-Drug Conjugates: New Horizons in Breast Cancer Therapy.

The advent of immunotherapy and antibody-drug conjugates (ADCs) have revolutionized breast cancer treatment, offering new hope to patients. However, challenges, such as resistance and limited efficacy in certain cases, remain. Recently, the combination of these therapies has emerged as a promising approach to address these challenges. ADCs play a crucial role by delivering cytotoxic agents directly to breast cancer cells, minimizing damage to healthy tissue and enhancing the tumor-killing effect. Concurrently, immunotherapies harness the body's immune system to recognize and eliminate cancer cells. This integration offers potential to overcome resistance mechanisms and significantly improve therapeutic outcomes. This review explores the rationale behind combining immunotherapies with ADCs, recent advances in this field, and the potential implications for breast cancer treatment.

NIR-triggered NO production combined with photodynamic therapy for tumor treatment

Photodynamic therapy (PDT), as one of the most promising cancer therapy methods, is still limited by several drawbacks, such as tissue hypoxia and shallow light penetration of blue-violet light (200–450 nm), and red light (750 nm) is more penetrating to tissues than blue-violet light, but still lower than near-red light (750–1350 nm). Therefore, we proposed a synergistic therapy system by combining the near-infrared light-triggered PDT with nitric oxide (NO)-based gas therapy to enhance the anti-tumor effects. Upconversion nanoparticles (UCNPs) were loaded with the photosensitizers of ZnPc and the NO donors of l-arginine (L-Arg) to obtain the nanocomposites of UCN@mSiO2@ZnPc@L-Arg. Under 980 nm laser irradiation, reactive oxygen species (ROS) could be produced for PDT and react with l-Arg to produce NO, which is previously reported to have a greater killing effect on tumor cells than ROS and also plays an important role in promoting PDT in our study. Both the in vitro and in vivo tests demonstrated that the combined therapy of PDT with NO therapy could enhance the tumor killing effect significantly compared with the unique application of PDT. The UCNPs-based nanocomposites are expected to be widely used in biomedicine for tumor inhibition.

Oncolytic Activity of Sindbis Virus with the Help of GM-CSF in Hepatocellular Carcinoma.

Hepatocellular carcinoma is a refractory tumor with poor prognosis and high mortality. Many oncolytic viruses are currently being investigated for the treatment of hepatocellular carcinoma. Based on previous studies, we constructed a recombinant GM-CSF-carrying Sindbis virus, named SINV-GM-CSF, which contains a mutation (G to S) at amino acid 285 in the nsp1 protein of the viral vector. The potential of this mutated vector for liver cancer therapy was verified at the cellular level and in vivo, respectively, and the changes in the tumor microenvironment after treatment were also described. The results showed that the Sindbis virus could effectively infect hepatocellular carcinoma cell lines and induce cell death. Furthermore, the addition of GM-CSF enhanced the tumor-killing effect of the Sindbis virus and increased the number of immune cells in the intra-tumor microenvironment during the treatment. In particular, SINV-GM-CSF was able to efficiently kill tumors in a mouse tumor model of hepatocellular carcinoma by regulating the elevation of M1-type macrophages (which have a tumor-resistant ability) and the decrease in M2-type macrophages (which have a tumor-promoting capacity). Overall, SINV-GM-CSF is an attractive vector platform with clinical potential for use as a safe and effective oncolytic virus.

Feature-Enhanced Artificial Neutrophils for Dual-Modal MR/NIR Imaging-Guided Cancer Therapy

Neutrophils release neutrophil elastase (ELANE) to kill a wide range of cancer cells through proteolytically liberating the CD95 death domain (DD) and initiating apoptotic pathway in cancer cells. However, current neutrophil-inspired strategies are restricted to single reactive oxygen species (ROS)-based killing and rarely involve coordinated multi-path tumor killing. Herein, we develop feature-enhanced artificial neutrophils (aNeu) to improve tumor therapy via dual-modal MR/NIR imaging-guided combined actions of cytotoxic porcine pancreatic elastase (PPE), ROS and the triggered protective immunity. We construct aNeu by loading PPE and NIR-responsive IR780 into glutathione-unlocked hollow MnO2 nanoparticles and then coating with neutrophil membrane. After stimulation-responsive activation inside tumor cells, the as-prepared aNeu can exhibit robust tumor killing effect and elicit adaptive immune response to promote tumor elimination. Moreover, MR/NIR imaging enable aNeu to monitor payload release and to anticipate therapeutic outcome. This feature-enhanced aNeu offers a new paradigm for neutrophil-inspired tumor therapy.

3D tumor spheroids promote activation, expansion, and anti-tumor effects of tumor-infiltrating lymphocytes in vitro

The adoptive immunotherapy mediated by tumor-infiltrating lymphocytes (TILs) has shown definite efficacy against various solid tumors. However, the inefficiency of the conventional method based on in vitro expansion of TILs fails to achieve the cell count and high tumor-killing activity required for therapeutic purposes. This study investigated the effect of 3D tumor spheroids on the activation and expansion of TILs in vitro, aiming to provide a novel approach for the expansion of TILs. We procured TILs and primary tumor cells from surgical samples of lung cancer patients and then compared the impacts of lung cancer cell line NCI-H1975 and primary lung cancer cells cultured under 2D and 3D conditions on the activation, expansion, and anti-tumor activity of TILs. Furthermore, we added the programmed cell death protein 1 (PD-1) antibody into the co-culture of primary tumor cells and TILs within a 3D environment to assess the effects of the antibody on TILs. The results showed that compared with 2D cultured tumor cells, the 3D cultured H1975 cells significantly enhanced the expansion of TILs, increasing the proportion of CD3+/CD8+ cells in TILs to 61.6%. The 3D primary tumor model also enhanced the proportion of CD3+/CD8+ cells in TILs (45.5%, 54.4%), induced apoptosis of tumor epithelial cells and decreased the overall tumor cells survival rate (16.7%) after co-culture. PD-1 antibodies further improved the in vitro expansion capacity of TILs mediated by 3D tumor spheroids, resulting in the proportions of 50.9% and 57.0% for CD3+/CD8+ cells and enhancing the antitumor activity significantly (reducing the overall tumor survival rate to 9.36%). In summary, the use of 3D tumor spheroids significantly promoted the expansion and improved the anti-tumor effect of TILs, and the use of the PD-1 antibody further promoted the expansion and tumor-killing effect of TILs.

Mesoporous Organosilica-Platinum Janus nanomotor coordinated by charge reversal for deep tumor penetration and promoted chemotherapy

Enhancing the diffusion capability of nanoparticles through rational engineering is an effective strategy for promoting the penetration of nanotherapeutic systems into tumors. However, the efficiency of diffusion remains inadequate due to the unchanged passive diffusion mode. Nanomotors hold promise for achieving deep tumor permeability due to their self-propelled motility. Developing smart-responsive nanomotor therapeutic systems for long circulation, deep tumor penetration, and well-timed drug release presents significant challenges. Herein, we design and synthesize a kind of nanomotor with charge reversal capability that shifts from negative to positive charge in response to weakly acidic tumor microenvironment on the base of the Janus nanostructure, which consists of the mesoporous organosilica degraded in response to glutathione and asymmetric Pt provided driving force by catalyzing endogenous H2O2 to decompose into O2. The cap-like Janus structure is prepared by a facile adsorption − reduction method. Such a nanomotor can achieve deep tumor penetration by the synergism of charge reversal and self-propelled motion. The drug-loaded nanomotor displays a superior tumor killing effect, which provides a promising strategy for the nano-chemotherapy system with deep penetration ability to break through the limitation of current tumor treatment.

Huaier enhances the tumor-killing effect and reverses gemcitabine-induced stemness by suppressing FoxM1

BackgroundGemcitabine is the first-line chemotherapy drug that can easily cause chemotherapy resistance. Huaier is a traditional Chinese medicine and shows an antitumor effect in pancreatic cancer, but whether it can enhance the gemcitabine chemotherapeutic response and the potential mechanism remain unknown. PurposeThis study was performed to explore the effect of Huaier in promoting the tumor-killing effect of gemcitabine and elucidate the possible mechanism in pancreatic cancer. MethodsCell Counting Kit-8 assays and colony formation assays were used to detect proliferation after different treatments. Protein coimmunoprecipitation was applied to demonstrate protein interactions. Nuclear protein extraction and immunofluorescence were used to confirm the intracellular localization of the proteins. Western blotting was performed to detect cell proliferation-related protein expression or cancer stem cell-associated protein expression. Sphere formation assays and flow cytometry were used to assess the stemness of pancreatic cancer cells. The in vivo xenograft model was used to confirm the inhibitory effect under physiological conditions, and immunohistochemistry was used to detect protein expression. ResultsHuaier suppressed the proliferation and stem cell-like properties of pancreatic cancer cells. We found that Huaier suppressed the expression of forkhead box protein M1 (FoxM1). In addition, Huaier inhibited FoxM1 function by blocking its nuclear translocation. Treatment with Huaier reversed the stemness induced by gemcitabine in a FoxM1-dependent manner. Furthermore, we verified the above results by an in vivo study, which reached the same conclusion as those in vitro. ConclusionOverall, this study illustrates that Huaier augments the tumor-killing effect of gemcitabine through suppressing the stemness induced by gemcitabine in a FoxM1-dependent way. These results indicate that Huaier can be applied to overcome gemcitabine resistance.

Abstract LB118: HM16390, a novel long-acting IL-2 analog with fine-tuned binding affinities to IL-2 receptor subunits for favorable safety profile, exhibits potent tumor killing effect in the various tumor syngeneic models

Abstract Although recombinant human IL-2 (rhIL-2, aldesleukin) produced approximately a 15% objective response rate in patients with renal cell carcinoma (RCC) and metastatic melanoma, its IL-2Rα (CD25)-biased binding and short half-life (t1/2 in human: 13-85 min) require a high dose and frequent dosing interval, leading to systemic toxicity such as vascular leak syndrome (VLS) and cytokine release syndrome (CRS). To overcome this limitation, various research groups are developing engineered IL-2 muteins with abolished CD25 binding affinity. While such IL-2 muteins may reduce CD25-mediated toxicity, there is a risk of a lopsided immune response. Furthermore, concomitantly reduced affinity to IL-2Rβ (CD122) may cause insufficient anti-tumor activity. We are developing HM16390, a long-acting IL-2 analog with a significantly increased binding affinity to CD122 for potent tumor killing effect. Simultaneously, optimal binding property to CD25 was introduced for a suppression of uncontrolled systemic immune response via peripheral Treg expansion. From these novel sequence modifications, HM16390 exhibited approximately 14-fold potent activity in human NK and CD8+ T cells compared to rhIL-2 and comparable activity with rhIL-2 in human Tregs (EC50 of STAT5 phosphorylation) without undesired release of cytokines associated with CRS. In B16F10 mouse model, HM16390 has a longer-lasting PK property (t1/2: 14.2~26.0 hr) after single subcutaneous (SC) administration. CD8+ T cells were significantly increased in peripheral blood along with a transient increase of peripheral Tregs, suggesting that HM16390 not only has a significant effect on expansion of CD8+ T cells but can simultaneously modulate exaggerated peripheral immune response. It is also noteworthy that, unlike in the peripheral, Tregs were drastically reduced in the tumor immune microenvironment, and CD8+ T cells were significantly increased. Next, in orthotopic model of mouse RCC (RENCA-luc cell implantation), across treatment groups, 40%(n=4/10) to 80%(n=8/10) of animals achieved complete tumor regression in dose-dependent manner after once weekly SC injection of HM16390 for 4 weeks. Furthermore, tumor nodules were not observed in lung and kidney after intravenous (IV) rechallenge of RENCA cells in the mice cured by HM16390 for at least 4 months after drug discontinuation. This indicates a long-term immunological memory response of generated memory cells by treatment of HM16390. In conclusion, HM16390 demonstrates potent and durable anti-tumor activity in various murine tumor models via its enhanced CD122 binding affinity, and incorporated optimal CD25 binding affinity may alleviate systemic toxicity by immunomodulatory role of peripheral Tregs. Citation Format: Sol-Bi Shin, Jinyoung Kim, Jaehyuk Choi, Seongju Jeong, Yunjae Kim, Jooyun Byun, Sungmin Bae, Daejin Kim, In Young Choi. HM16390, a novel long-acting IL-2 analog with fine-tuned binding affinities to IL-2 receptor subunits for favorable safety profile, exhibits potent tumor killing effect in the various tumor syngeneic models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB118.

CD133 ligand-enhanced etoposide-liposome complex for targeted killing of lung cancer cells.

Lung cancer has a high incidence rate and a low cure rate, hence the urgent need for effective treatment methods. Current lung cancer drugs have several drawbacks, including low specificity, poor targeting, drug resistance, and irreversible damage to normal tissues. Therefore, there is a need to develop a safe and effective new drug that can target and kill tumor cells. In this study, we combined nanotechnology and biotechnology to develop a CD133 ligand-modified etoposide-liposome complex (Lipo@ETP-CD133) for targeted therapy of lung cancer. The CD133 ligand targeted lung cancer stem cells, causing the composite material to aggregate at the tumor site, where high levels of ETP liposomes could exert a strong tumor-killing effect. Our research results demonstrated that this nano-drug had efficient targeting and tumor-killing effects, indicating its potential for clinical application.

Abstract 2358: YH41723 (IMC-202), a Novel TIGITxPD-L1 bispecific antibody, leads to potent anti-tumor immunity through T cell engaging and T/NK cell activation

Abstract Immune checkpoint inhibitors (ICIs) have been making innovative advances in current cancer therapy. In particular, the PD-L1/PD-1 blockades changed the paradigm of anti-cancer treatment, showing high efficiency compared to conventional therapy. However, drug resistance has been observed in many patients receiving PD-1/PD-L1 monoclonal antibodies (mAbs), and there are still many limitations in restoring T cell. To overcome this, various ICI targets including T cell immunoreceptor with Ig and ITIM domain (TIGIT) are being studied. TIGIT is a T cell co-inhibitory receptor, highly expressed on regulatory T (Treg) cells and memory T cells and natural killer (NK) cells. In combination with PD-1/PD-L1 inhibition, the activation of CD226 through the blocking of TIGIT/PVR ligation is important for T cell activation. In this study, we demonstrated the synergistic effect that can be obtained by simultaneously blocking of PD-L1 and TIGIT and effect of T cell engager function using TIGITxPD-L1 bispecific antibody (BsAb). We generated an anti-TIGITxPD-L1 BsAb, YH41723 (IMC-202), with Fc-engineering to enhance the effector function. In order to confirm superior efficacy of YH41723 compared to combination of two monoclonal antibodies, PD-L1 mAb+TIGIT mAb, we verified the CD8+ T cell-mediated tumor killing effect by T cell engager function of YH41723. We also observed strong antibody-dependent cell-mediated cytotoxicity (ADCC) effect of YH41723 against various cancer cell lines. In addition, YH41723 showed superior anti-tumor efficacy than combination treatment in NK cell-mediated tumor killing assay. We further confirmed the significant Treg cell depletion efficacy of YH41723 in vitro compared to combination. We tested in vivo anti-cancer efficacy of YH41723 in hPD-L1 KI CT26 with BALB/c-H/K-dKO mouse models (B cell-deficient mice). As a result, YH41723 showed superior tumor growth inhibition effect compared with anti-PD-L1 mAb and anti-TIGIT mAb combination. Even, 7 of 8 mice showed complete regression in 30 mg/kg dosing group. 60 days after the last administration, we further performed tumor re-challenge test. The tumor-free state of tumor re-challenged mice was sustained, indicating that the immune memory was generated by YH41723. Taken together, YH41723 showed strong efficacy in NK/T cell activation and Treg depletion in vitro and excellent anti-tumor efficacy in vivo, supporting that YH41723 as an effective anti-cancer immunotherapy and combination candidate with other ICIs. Citation Format: Min Hyeok Jee, Young Bong Park, Byeong-Yun An, Hee Ra Jung, Eunjung Lee, Jun Hwan Kim, Ji Eun Park, Ji Young Yoon, Seung Mi Jeong, Yang Kyun Ryu, Sung Ho Kim, Heung Tae Kim, Se-Woong Oh, Yeol Hong Kim. YH41723 (IMC-202), a Novel TIGITxPD-L1 bispecific antibody, leads to potent anti-tumor immunity through T cell engaging and T/NK cell activation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2358.

Abstract 6829: Identification of immune suppressive features in tumor-associated endothelial cells (TECs) in EGFR-mutant non-small cell lung cancer via single-cell RNA sequencing

Abstract Introduction: Within the tumor microenvironment (TME), tumor-associated endothelial cells (TECs) exhibit distinct features from normal cells, and diverse phenotypes of TECs result in intratumoral heterogeneity. Here, we aimed to characterize the phenotypes of the TECs of non-small cell lung cancer (NSCLC), identify distinct features that are pivotal in tumor progression, and discover potential therapeutic applications. Methods: We performed single-cell RNA sequencing (scRNA-seq) from 128 NSCLC patients to include I (N=52), II (N=18), III (N=21), and IV (N=14), and compared them with normal cells (N=24). Epidermal growth factor receptor (EGFR)-mutant accounted for 69 samples. EGFR-wild (N=35) was further classified as programmed death-ligand 1 (PD-L1) high (N=14) and low (N=21) with PD-L1 high defined as tumor proportion score > 50%. Results: Twelve distinct EC types were characterized based on clinical information, including EGFR mutations and PD-L1 expression. We classified our subset as normal cells and tumor-enriched ECs, which were further classified as EGFR-wild or mutant ECs. Compared to normal cells, phenotypes such as activated post-capillary veins (APCVs), tip ECs, and endothelial mesenchymal transition (endoMT) ECs were predominantly observed in all tumor-enriched ECs. In EGFR-mutant ECs, ribosomal ECs, and vascular mimicry (VM) ECs were primarily enriched. Trajectory analysis showed that endoMT and VM ECs had lineage tracing of fibroblasts and epithelial cells, respectively. By clinical stage, APCVs, tip ECs, endoMT, and VM ECs were more enriched at advanced stages. PD-L1-high subset had higher expression of adhesion molecules, APCVs, and median transmigration score than other phenotypes. Also, high endothelial venules (HEVs) mediating lymphocyte trafficking to lymphoid organs were enriched in high PD-L1 subset. In the APCVs of EGFR-mutant group, there were interactions related to immune cell suppression and interactions of chemokines/chemokine receptors involved in recruitment. Conclusion: Our findings reveal distinct phenotypes of ECs, including the enrichment of APCVs, tip ECs, and endoMT ECs in all tumor-enriched EC populations, as well as VM ECs in EGFR-mutant ECs. APCVs, which is abundant high PD-L1 subset, play a crucial role in the transmigration progress of immune cells across vascular endothelium. In EGFR-mutant NSCLC, dysfunctional immune cells are recruited into the tumor, along with relatively low transmigration, resulting in poor tumor-killing effect. Citation Format: Su-Jin Choi, Jii Bum Lee, Kyoung-Ho Pyo, Gang-Taik Lee, YoungJoon Park, You Won Lee, Mi Ran Yun, Kyumin Lim, JuHyeon Lee, Min Hee Hong, Sun Min Lim, Byoung Chul Cho. Identification of immune suppressive features in tumor-associated endothelial cells (TECs) in EGFR-mutant non-small cell lung cancer via single-cell RNA sequencing [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6829.

An Advanced Intrahepatic Cholangiocarcinoma Patient Benefits from Personalized Immunotherapy.

Advanced intrahepatic cholangiocarcinoma (ICC) is a highly aggressive malignancy characterized by limited response to standard therapeutic modalities, such as radiotherapy, chemotherapy, and targeted therapy. The prognosis for patients with advanced ICC is exceedingly bleak, with an overall survival of less than 1 year. In recent years, personalized neoantigen vaccines have emerged as a promising approach to augment the immune response against tumors. Clinical investigations are currently underway to evaluate the efficacy of neoantigen-based peptide, DNA, and dendritic cell vaccines. Herein, we present a noteworthy case of advanced ICC patients who experienced disease progression following relapse and subsequently received immunotherapy with a personalized neoantigen nanovaccine. This innovative treatment strategy involved the administration of a custom-designed neoantigen-based peptide nanovaccine tailored to the patient's specific gene mutation profile subsequent to failure of first-line therapy. The clinical efficacy and anti-tumor immune responses were evaluated using various methods, including imaging, interferon-γ ELISPOT assay, and intracellular cytokine staining. Notably, the neoantigen nanovaccine elicited a robust and specific tumor-killing effect mediated by T cells, resulting in a durable response lasting up to 25 months. These findings highlight the potential of neoantigen-based immunotherapy as a novel therapeutic avenue for the management of advanced ICC.

Bifunctional molecular probe targeting tumor PD-L1 enhances anti-tumor efficacy by promoting ferroptosis in lung cancer mouse model

PurposeImmune checkpoint inhibitors (ICIs) targeting tumor-specific PD-1/PD-L1 significantly improve the overall survival rate of patients with advanced cancer by reactivating the immune system to attack cancer cells. To explore their tumor killing effect, we used the radionuclide iodine-131 (131I) to label the anti-PD-L1 antibody Atezolizumab (131I-PD-L1 mAb). MethodWe prepared the radioimmunoassay molecular probe 131I-PD-L1 mAb by the chloramine-T method and evaluated its affinity using Lewis lung cancer (LLC) cells. The uptake of 131I-PD-L1 mAb by transplanted tumors was examined through SPECT and its in vivo distribution. We then compared the in vitro and in vivo anti-tumor efficacy of groups treated with control, PD-L1 mAb, 131I-PD-L1 mAb, and 131I-PD-L1 mAb + PD-L1 mAb combined treatment. We performed H&E staining to examine the changes in tumor, as well as the damage in major tissues and organs caused by potential side effects. The anti-tumor mechanism of 131I-PD-L1 mAb was analyzed by Western blot, RT-qPCR and immunohistochemistry (IHC). Result131I-PD-L1 mAb was highly stable and specific, and easily penetrated into tumor. 131I-PD-L1 mAb suppressed cancer cell proliferation in vitro, and inhibited tumor growth in vivo by inducing ferroptosis, thus prolonging the survival of experimental animals while demonstrating biological safety. ConclusionTherefore, our study suggested that 131I-PD-L1 mAb affected the expression of tumor-related factors through β-rays and thus promoted ferroptosis in tumor. Combined treatment showed better anti-tumor effect compared to single ICI treatment.

A Smart DNA Hydrogel Enables Synergistic Immunotherapy and Photodynamic Therapy of Melanoma.

Immunotherapy faces insufficient immune activation and limited immune effectiveness. Herein, we report a smart DNA hydrogel that enables the release of multivalent functional units at the tumor site to enhance the efficacy of immunotherapy. The smart DNA hydrogel was assembled from two types of ultra-long DNA chains synthesized via rolling circle amplification. One DNA chain contained immune adjuvant CpG oligonucleotides and polyaptamers for loading natural killer cell-derived exosomes; the other chain contained multivalent G-quadruplex for loading photodynamic agents. DNA chains formed DNA hydrogel through base-pairing. HhaI restriction endonuclease sites were designed between functional units. Upon stimuli in the tumor sites, the hydrogel was effectively cleaved by the released HhaI and disassembled into functional units. Natural killer cell-derived exosomes played an anti-tumor role, and the CpG oligonucleotide activated antigen-presenting cells to enhance the immunotherapy. Besides the tumor-killing effect of photodynamic therapy, the generated cellular debris acted as an immune antigen to further enhance the immunotherapeutic effect. In a mouse melanoma orthotopic model, the smart DNA hydrogel as a localized therapeutic agent, achieved a remarkable tumor suppression rate of 91.2 %. The smart DNA hydrogel exhibited enhanced efficacy of synergistic immunotherapy and photodynamic therapy, expanding the application of DNA materials in biomedicine.

Liposome encapsulated polydopamine nanoparticles: Enhancing ferroptosis and activating hypoxia prodrug activity

The short lifespan of active oxygen species and depressed O2 level during ferroptosis treatment in tumor cells weaken ferroptosis therapy. How to improve the utilization efficiency of active oxygen species generated in real time is pivotal for anticancer treatment. Herein, the tirapazamine (TPZ) loaded polydopamine-Fe nanoparticles (PDA-Fe-TPZ) was modified with unsaturated liposome (Lip), which was constructed to overcome the drawbacks of traditional ferroptosis therapy. The Lip@PDA-Fe-TPZ nanoliposomes can react with H2O2 to produce •OH by Fenton reaction, which then attacks Lip and transforms into radical intermediate (L•) and phospholipid peroxide radical (LOO•) to avoid the annihilation of •OH. The introduced Lip enhances lipid peroxidation and promotes oxygen consumption, resulting in increased hypoxia at tumor site. The introduced TPZ can be triggered by reductase in tumor cells under hypoxia, which can reduce to transient oxidative free radicals by reductase enzymes and destroy the structure of the surrounding biomacromolecules, thus achieving the synergistic treatment of ferroptosis and chemotherapy. In this work, we organically combined enhanced ferrroptosis with hypoxic activated chemotherapy to achieve efficient and specific tumor killing effect, which can sever as a promising treatment of cancer in the future.

Effect of signal peptide optimized by site-directed mutagenesis on the function of chimeric antigen receptor T cells

Signal peptides (SP) are involved in regulating the secretion level and transmembrane translocation of chimeric antigen receptors (CAR), which is crucial for CAR-T cells. This study aimed to optimize the SP sequence by site-directed mutagenesis and investigate its impact on the killing function of CD19-CAR-T. Firstly, CAR vectors targeting CD19 containing wild-type SP (SP-wtY) or two mutant SP (SP-muK or SP-muR) were constructed using gene synthesis and molecular cloning techniques. The successfully constructed vector was packaged with lentivirus, and T cells were infected. The transfection efficiency of T cells was detected by flow cytometry, while the killing effect on target cells was assessed using the calcein release method. The secretion levels of cytokines interferon-γ (IFN-γ) and interferon-α (TNF-α) were measured using enzyme linked immunosorbent assay (ELISA). The results showed that successful construction of recombinant lentivirus plasmids with wild type and signal peptide mutation. After the transferring the lentivirus into T cells, the transfection efficiency of CD19-CAR carrying three signal peptides (SP-wtY, SP-muK, or SP-muR) were 33.9%, 35.5%, and 36.8%, respectively. Further killing assay showed that the tumor-killing effect of SP-muR cells was significantly higher than that of SP-muK and SP-wtY cells. When the ratio of effector to target was 10:1, the secretion levels of cytokines IFN-γ and TNF-α of CAR-T cells of the SP-muR group were significantly higher than those in SP-muK and SP-wtY groups. In summary, this study revealed that increasing the N-terminal positive charge of the signal peptide can improve the expression efficiency of CAR and promote the killing of CD19+ target cells. These findings provide a scientific basis the optimization and clinical application of CAR structure.

Combination Immunotherapy of Oncolytic Flu-Vectored Virus and Programmed Cell Death 1 Blockade Enhances Antitumor Activity in Hepatocellular Carcinoma.

Oncolytic viruses (OVs) are appealing anti-tumor agents. But it is limited in its effectiveness. In this study, we used combination therapy with immune checkpoint inhibitor to enhance the antitumor efficacy of OVs. Using reverse genetics technology, we rescued an oncolytic influenza virus with the name delNS1-GM-CSF from the virus. After identifying the hemagglutination and 50% tissue culture infectivedose (TCID50) of delNS1-GM-CSF, it was purified, and the viral morphology was observed under electron microscopy. Reverse transcription quantitative-polymerase chain reaction (RT-qPCR) was used to identify the level of GM-CSF expression in delNS1-GM-CSF, and the GM-CSF expression level was determined after infection with delNS1-GM-CSF by enzyme linked immunosorbent assay (ELISA). To study the tumor-killing effect of delNS1-GM-CSF, we utilized the hepatocellular carcinoma (HCC) tumor-bearing mouse model. To examine signaling pathways, we performed transcriptome sequencing on mouse tumor tissue and applied western blotting to confirm the results. Changes in T-cell infiltration in HCC tumors following treatment were analyzed using flow cytometry and immunohistochemistry. DelNS1-GM-CSF can target and kill HCCs without damaging normal hepatocytes. DelNS1-GM-CSF combined with programmed cell death 1 blockade therapy enhanced anti-tumor effects and significantly improved mouse survival. Further, we found that combination therapy had an antitumor impact via the janus kinase-signal transducer and activator of transcription (JAK2-STAT3) pathway as well as activated CD4+ and CD8+T cells. Interestingly, combined therapy also showed promising efficacy in distant tumors. DelNS1-GM-CSF is well targeted. Mechanistic investigation revealed that it functions through the JAK2-STAT3 pathway. Combination immunotherapies expected to be a novel strategy for HCC immunotherapy.

Devastating the Supply Wagons: Multifaceted Liposomes Capable of Exhausting Tumor to Death via Triple Energy Depletion.

The anabolism of tumor cells can not only support their proliferation, but also endow them with a steady influx of exogenous nutrients. Therefore, consuming metabolic substrates or limiting access to energy supply can be an effective strategy to impede tumor growth. Herein, a novel treatment paradigm of starving-like therapy-triple energy-depleting therapy-is illustrated by glucose oxidase (GOx)/dc-IR825/sorafenib liposomes (termed GISLs), and such a triple energy-depleting therapy exhibits a more effective tumor-killing effect than conventional starvation therapy that only cuts off one of the energy supplies. Specifically, GOx can continuously consume glucose and generate toxic H2O2 in the tumor microenvironment (including tumor cells). After endocytosis, dc-IR825 (a near-infrared cyanine dye) can precisely target mitochondria and exert photodynamic and photothermal activities upon laser irradiation to destroy mitochondria. The anti-angiogenesis effect of sorafenib can further block energy and nutrition supply from blood. This work exemplifies a facile and safe method to exhaust the energy in a tumor from three aspects and starve the tumor to death and also highlights the importance of energy depletion in tumor treatment. It is hoped that this work will inspire the development of more advanced platforms that can combine multiple energy depletion therapies to realize more effective tumor treatment.