Synergistic Therapeutic Strategy Research Articles

Anti-EGFR bioengineered bacterial outer membrane vesicles as targeted immunotherapy candidate in triple-negative breast tumor murine model

Cancer immunotherapy employing checkpoint inhibitors holds great promise across diverse cancers; nonetheless, a substantial proportion of patients (ranging from 55 to 87%) remain unresponsive to this treatment. To amplify therapeutic efficiency, we propose a synergistic therapeutic strategy that entails the deployment of targeted nano-sized particles carrying Toll-like receptor (TLR) agonists to the tumor site. This innovative approach seeks to activate intratumoral antigen-presenting cells using bioengineered outer membrane vesicles (OMVs) derived from gram-negative bacteria. These OMVs possess inherent attributes of surface-exposed immune stimulators and TLR-activating components, rendering them intriguing candidates for investigation. These OMVs were meticulously designed to selectively target cancer cells exhibiting an overexpression of epidermal growth factor receptor (EGFR). To gauge the precision of this targeting, the conducted affinity-based assays aimed at determining the equilibrium dissociation constant of the single-chain variable fragment employed for this purpose. In vitro experiments confirmed the OMVs' proficiency in adhering to EGFR-overexpressed cancer cells. Moreover, the evaluation extended to an in vivo context, where the therapeutic effect of nanovesicles was appraised within the tumor microenvironment of the triple-negative breast cancer mouse model. Notably, both intraperitoneal and intratumoral administrations of nanovesicles exhibited the ability to activate natural killer cells and skew M2 macrophage towards an M1 phenotype. The combined scrutiny of in vitro and in vivo findings underscores the potential efficiency of OMVs as a promising strategy for future anti-tumor endeavors.

Quorum Sensing Interference Assisted Therapy-Based Magnetic Hyperthermia Amplifier for Synergistic Biofilm Treatment.

Biofilms offer bacteria a physical and metabolic barrier, enhancing their tolerance to external stress. Consequently, these biofilms limit the effectiveness of conventional antimicrobial treatment. Recently, quorum sensing (QS) has been linked to biofilm's stress response to thermal, oxidative, and osmotic stress. Herein, a multiple synergistic therapeutic strategy that couples quorum sensing interference assisted therapy (QSIAT)-mediated enhanced thermal therapy with bacteria-triggered immunomodulation in a single nanoplatform, is presented. First, as magnetic hyperthermia amplifier, hyaluronic acid-coated ferrite (HA@MnFe2 O4 ) attenuates the stress response of biofilm by down-regulating QS-related genes, including agrA, agrC, and hld. Next, the sensitized bacteria are eliminated with magnetic heat. QS interference and heat also destruct the biofilm, and provide channels for further penetration of nanoparticles. Moreover, triggered by bacterial hyaluronidase, the wrapped hyaluronic acid (HA) decomposes into disaccharides at the site of infection and exerts healing effect. Thus, by reversing the bacterial tissue invasion mechanism for antimicrobial purpose, tissue regeneration following pathogen invasion and thermal therapy is successfully attained. RNA-sequencing demonstrates the QS-mediated stress response impairment. In vitro and in vivo experiments reveal the excellent antibiofilm and anti-inflammatory effects of HA@MnFe2 O4 . Overall, QSIAT provides a universal enhancement strategy for amplifying the bactericidaleffects of conventional therapy via stress response interference.

A NIR-Activated and Mild-Temperature-Sensitive Nanoplatform with an HSP90 Inhibitor for Combinatory Chemotherapy and Mild Photothermal Therapy in Cancel Cells.

Mild photothermal therapy (PTT) shows great potential to treat cancers while avoiding unwanted damage to surrounding normal cells. However, the efficacy of mild PTT is normally moderate because of the low hyperthermia temperature and limited light penetration depth. Chemotherapy has unlimited penetration but often suffers from unsatisfactory efficacy in view of the occurrence of drug resistance, suboptimal drug delivery and release profile. As a result, the combinatory of chemotherapy and mild PTT would integrate their advantages and overcome the shortcomings. Herein, we synthesized an NIR-activatable and mild-temperature-sensitive nanoplatform (BDPII-gel@TSL) composed of temperature-sensitive liposomes (TSL), heat shock protein 90 (HSP90) inhibitor (geldanamycin) and photothermal agent (BDPII), for dual chemotherapy and mild PTT in cancer cells. BDPII, constructed with donor-acceptor moieties, acts as an excellent near-infrared (NIR) photothermal agent (PTA) with a high photothermal conversion efficiency (80.75%). BDPII-containing TSLs efficiently produce a mild hyperthermia effect (42 °C) under laser irradiation (808 nm, 0.5 W cm-2). Importantly, the phase transformation of TSL leads to burst release of geldanamycin from BDPII-gel@TSL, and this contributes to down-regulation of the overexpression of HSP90, ensuring efficient inhibition of cancer cell growth. This research provides a dual-sensitive synergistic therapeutic strategy for cancer cell treatment.

The selective activator protein-1 inhibitor T-5224 regulates the IRF4/MYC axis and exerts cooperative antimyeloma activity with bortezomib

The activating protein-1 (AP-1) transcription factors (TFs) have been associated with many different cancer types and are promising therapeutic targets in logical malignancies. However, the mechanisms of their role in multiple myeloma (MM) remain elusive. The present study determined and compared the mRNA and protein expression levels of the AP-1 family member JunB in CD138+ mononuclear cells from MM patients and healthy donors. Herein, we investigated the effect of T-5224, an inhibitor of JUN/AP-1, on MM. We found that the cytotoxicity of T-5224 toward myeloma is due to its ability to induce cell apoptosis, inhibit proliferation, and induce cell cycle arrest by increasing the levels of cleaved caspase3/7 and concomitantly inhibiting the IRF4/MYC axis. We also noticed that siJunB-mediated deletion of JunB/AP-1 enhanced MM cell apoptosis and affected cell proliferation. The software PROMO was used in the present study to predict the AP-1 TF that may bind the promoter region of IRF4. We confirmed the correlation between JunB/AP-1 and IRF4. Given that bortezomib (BTZ) facilitates IRF4 degradation in MM cells, we applied combination treatment of BTZ with T-5224. T-5224 and BTZ exerted synergistic effects, and T-5224 reversed the effect of BTZ on CD138+ primary resistance in MM cells, in part due to suppression of the IRF4/MYC axis. Our results suggest that targeting AP-1 TFs is a promising therapeutic strategy for MM. Additionally, targeting both AP-1 and IRF4 with T-5224 may be a synergistic therapeutic strategy for this clinically challenging subset of MM.

Codelivery of ERCC2 small interfering RNA and cisplatin with macrophage-derived mimetic nanovesicles for enhanced bladder cancer treatment.

Cisplatin-based chemotherapy plays a vital role in the management of muscle-invasive bladder cancer (MIBC); however, off-tumor toxicity and resistance often lead to cancer recurrence and eventual treatment failure. The loss of function of the nucleotide excision repair gene excision repair cross-complementing rodent repair deficiency gene 2 ( ERCC2 ) in cancer cells correlates with sensitivity to cisplatin, while its overexpression causes cisplatin resistance. Small interfering RNA (siRNA) knockdown of ERCC2 combined with cisplatin treatment may improve therapeutic outcomes in patients with bladder cancer. Here, we aimed to develop macrophage-derived mimetic nanovesicles (MNVs) as a nanoplatform for the simultaneous delivery of cisplatin and ERCC2 siRNA for enhancing the efficacy of bladder cancer chemotherapy. The cellular uptake, gene down-regulation, tumor inhibition effects, and biosafety of the synthesized nanodrugs (MNV-Co) as a synergistic therapeutic strategy for MIBC were evaluated in vitro and in vivo . The results indicated high efficacy of MNV-Co against MIBC and low off-tumor toxicity. Furthermore, by down-regulating ERCC2 mRNA and protein levels, MNV-Co improved chemosensitivity, promoted cancer cell apoptosis, and effectively suppressed tumor growth. This study presents a potential approach for delivering cisplatin and ERCC2 siRNA concurrently to treat bladder cancer using a biomimetic nanosystem.

NIR-Triggered On-Demand Nitric Oxide Release for Enhanced Synergistic Phototherapy of Hypoxic Tumor.

Hypoxia of tumor microenvironments is a major factor restricting tumor treatment, which causes progression and metastasis of tumor. The hypoxic tumor microenvironment not only makes the traditional treatment method, such as chemotherapy, ineffective but also hinders the O2-dependent treatments, such as photodynamic therapy (PDT). Recently, stimuli-responsive nitric oxide (NO) donors have attracted extensive research interest in hypoxic tumor treatment because the NO release process is O2-independent. Besides, NO can distribute more uniformly than drug molecules and more widely than the PDT-generated active species due to its strong diffusion ability (200 μm in cells) and long lifetime (2 s in cells). Encouraged by these advantages, a near infrared light-triggered NO release polymeric nanoplatform (P1-CapNO NPs) was constructed by a thermally sensitive NO release unit, a photothermal unit, and a hydrophilic polyethylene glycol unit. P1-CapNO NPs possess strong absorption in the NIR region (the wavelength of maximal absorption peak was 790 nm with a molar absorption coefficient of 2.4 × 105 M-1 cm-1), great photothermal conversion efficiency (23.8%), and NO release ability (the released NO concentration can reach 1.3 μM) under 808 nm laser irradiation. Owing to these advantages, the great synergistic antitumor effect can be achieved in vitro and in vivo even under the hypoxic environment. The synergistic therapeutic strategy in this work could bypass the obstacles caused by hypoxia in tumor treatment and provide a reference for building a NO-involved therapeutic platform.

Aggregation-induced emission photosensitizer/bacteria biohybrids enhance Cerenkov radiation-induced photodynamic therapy by activating anti-tumor immunity for synergistic tumor treatment

Cerenkov radiation-induced photodynamic therapy (CR-PDT) gets rid of the limited tissue penetration depth of the external light source and provides a feasible scheme for the PDT excited by the internal light. However, due to the low luminescence intensity of Cerenkov radiation, CR-PDT alone cannot effectively inhibit tumor growth, curbing the potential clinical translation of CR-PDT. Herein, we reported an AIE-PS/bacteria biohybrid (EcN@TTVP) composed of Escherichia coli Nissle 1917 (EcN) loaded with aggregation-induced emission photosensitizer (AIE-PS) termed TTVP, which enhanced CR-PDT by activating anti-tumor immunity for synergistic tumor treatment. The preferential tumor-colonized EcN@TTVP and radiopharmaceutical 18F-fluorodeoxyglucose (18F-FDG) were administered sequentially to enable them to co-enrich in the tumor site, thereby triggering CR-PDT and promoting immunogenic tumor cell death. Most importantly, EcN acting as immunoadjuvants enhanced the maturation of dendritic cells (DCs) and priming of cytotoxic T cells (CTLs). Therefore, under the synergistic treatment of CR-PDT and immunotherapy, AIE-PS/bacteria biohybrids resulted in either efficient tumor remission or a survival prolongation in tumor-bearing mice, which presented significant advantages over single CR-PDT. Remarkably, no obvious toxic effects were observed during the treatment. In this study, we proposed a synergistic therapeutic strategy based on EcN@TTVP for combined CR-PDT and immunotherapy against tumors. Moreover, this strategy may have great potential in clinical translation and provide references for deep-seated tumor treatment. Statement of significancePDT is restricted due to the shallow penetration depth of light into tumor tissues. Using CR as the excitation light source for PDT can overcome the aforementioned issue and greatly expand the application of PDT. However, the low efficacy of single CR-PDT limits further its applications. Therefore, the design and development of feasible strategies to improve the efficacy of CR-PDT are of immediate importance. Introducing probiotics to our study can be used not only as tumor-targeting carriers of photosensitizers but also as immunoadjuvants. Under co-stimulation by immunogenic tumor cell death triggered by CR-PDT and probiotics acting as immunoadjuvants, anti-tumor immune responses were effectively activated, thus remarkably enhancing the efficacy of CR-PDT.

Thermal immuno-nanomedicine: A new strategy for cancer treatment.

Thermal immuno-nanomedicine: A new strategy for cancer treatment.

Functional plasticity of neutrophils after low- or high-dose irradiation in cancer treatment - A mini review.

Over the last several decades, radiotherapy has been considered the primary treatment option for a broad range of cancer types, aimed at prolonging patients' survival and slowing down tumor regression. However, therapeutic outcomes of radiotherapy remain limited, and patients suffer from relapse shortly after radiation. Neutrophils can initiate an immune response to infection by releasing cytokines and chemokines to actively combat pathogens. In tumor immune microenvironment, tumor-derived signals reprogram neutrophils and induce their heterogeneity and functional versatility to promote or inhibit tumor growth. In this review, we present an overview of the typical phenotypes of neutrophils that emerge after exposure to low- and high-dose radiation. These phenotypes hold potential for developing synergistic therapeutic strategies to inhibit immunosuppressive activity and improve the antitumor effects of neutrophils to render radiation therapy as a more effective strategy for cancer patients, through tumor microenvironment modulation.

Anti-BCMA surface engineered biomimetic photothermal nanomissile enhances multiple myeloma cell apoptosis and overcomes the disturbance of NF-κB signaling in vivo

Conventional chemotherapy for multiple myeloma (MM) faces the challenges of a low complete remission rate and transformation to recurrence/refractory. The current MM first-line clinical drug Bortezomib (BTZ) faces the problem of enhanced tolerance and nonnegligible side effects. B cell maturation antigen (BCMA), for its important engagement in tumor signaling pathways and novel therapy technologies such as Chimeric antigen receptor T-Cell immunotherapy (CAR-T) and Antibody Drug Conjugate (ADC), has been identified as an ideal target and attracted attention in anti-MM therapy. Emerging nanotechnology provided feasible methods for drug delivery and new therapeutic strategies such as photothermal therapy (PTT). Herein, we developed a BCMA-Targeting biomimetic photothermal nanomissile BTZ@BPQDs@EM @anti-BCMA (BBE@anti-BCMA) by integration of BTZ, black phosphorus quantum dots (BPQDs), Erythrocyte membrane (EM) and BCMA antibody (anti-BCMA). We hypothesized that this engineered nanomissile could attack tumor cells in triple ways and achieve effective treatment of MM. Consequently, the intrinsic biomimetic nature of EM and the active targeting property of anti-BCMA enhanced the accumulation of therapeutic agents in the tumor site. Besides, owing to the decrease in BCMA abundance, the potential apoptosis-inducing ability was revealed. With the support of BPQDs' photothermal effect, Cleaved-Caspase-3 and Bax signal increased significantly, and the expression of Bcl-2 was inhibited. Furthermore, the synergistic photothermal/chemo therapy can effectively inhibit tumor growth and reverse the disorder of NF-κB in vivo. Importantly, this biomimetic nanodrug delivery system and antibody induced synergistic therapeutic strategy efficiently killed MM cells with ignorable systemic toxicity, which is a promising method for the future anticancer treatment of hematological malignancies in clinics.

Multifunctional AIE Nanosphere-Based "Nanobomb" for Trimodal Imaging-Guided Photothermal/Photodynamic/Pharmacological Therapy of Drug-Resistant Bacterial Infections.

Injudicious or inappropriate use of antibiotics has led to the prevalence of drug-resistant bacteria, posing a huge menace to global health. Here, a self-assembled aggregation-induced emission (AIE) nanosphere (AIE-PEG1000 NPs) that simultaneously possesses near-infrared region II (NIR-II) fluorescence emissive, photothermal, and photodynamic properties is prepared using a multifunctional AIE luminogen (AIE-4COOH). The AIE-PEG1000 NPs were encapsulated with teicoplanin (Tei) and ammonium bicarbonate (AB) into lipid nanovesicles to form a laser-activated "nanobomb" (AIE-Tei@AB NVs) for the multimodal theranostics of drug-resistant bacterial infections. In vivo experiments validate that the "nanobomb" enables high-performance NIR-II fluorescence, infrared thermal, and ultrasound (AB decomposition during the photothermal process to produce numerous CO2/NH3 bubbles, which is an efficient ultrasound contrast agent) imaging of multidrug-resistant bacteria-infected foci after intravenous administration of AIE-Tei@AB NVs followed by 660 nm laser stimulation. The highly efficient photothermal and photodynamic features of AIE-Tei@AB NVs, combined with the excellent pharmacological property of rapidly released Tei during bubble generation and NV disintegration, collectively promote broad-spectrum eradication of three clinically isolated multidrug-resistant bacteria strains and rapid healing of infected wounds. This multimodal imaging-guided synergistic therapeutic strategy can be extended for the theranostics of superbugs.

Inhibition of the mitochondrial pyruvate carrier simultaneously mitigates hyperinflammation and hyperglycemia in COVID-19.

The relationship between diabetes and coronavirus disease 2019 (COVID-19) is bidirectional: Although individuals with diabetes and high blood glucose (hyperglycemia) are predisposed to severe COVID-19, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection can also cause hyperglycemia and exacerbate underlying metabolic syndrome. Therefore, interventions capable of breaking the network of SARS-CoV-2 infection, hyperglycemia, and hyperinflammation, all factors that drive COVID-19 pathophysiology, are urgently needed. Here, we show that genetic ablation or pharmacological inhibition of mitochondrial pyruvate carrier (MPC) attenuates severe disease after influenza or SARS-CoV-2 pneumonia. MPC inhibition using a second-generation insulin sensitizer, MSDC-0602K (MSDC), dampened pulmonary inflammation and promoted lung recovery while concurrently reducing blood glucose levels and hyperlipidemia after viral pneumonia in obese mice. Mechanistically, MPC inhibition enhanced mitochondrial fitness and destabilized hypoxia-inducible factor-1α, leading to dampened virus-induced inflammatory responses in both murine and human lung macrophages. We further showed that MSDC enhanced responses to nirmatrelvir (the antiviral component of Paxlovid) to provide high levels of protection against severe host disease development after SARS-CoV-2 infection and suppressed cellular inflammation in human COVID-19 lung autopsies, demonstrating its translational potential for treating severe COVID-19. Collectively, we uncover a metabolic pathway that simultaneously modulates pulmonary inflammation, tissue recovery, and host metabolic health, presenting a synergistic therapeutic strategy to treat severe COVID-19, particularly in patients with underlying metabolic disease.

A Synergistic Antibacterial Platform Combining Low–Temperature Photothermal Therapy and Antibiotic Therapy

Antimicrobial resistance has brought great burden to global public health. Alternative strategies are needed to reduce the development of drug resistance. Herein, we have developed an effective synergistic antibacterial strategy combining low–temperature photothermal therapy (LT–PTT) with antibiotic therapy, improving the bactericidal efficiency to avoid antimicrobial resistance. Copper sulfide templated with bovine serum albumin (CuS–BSA) nanoparticles were selected as the photothermal agent, and co–loaded into the hydrogel (Gel) with mupirocin. The Gel could slow down the release rate of CuS–BSA and mupirocin, thereby prolonging the effective drug reaction time. More importantly, when applying near–infrared laser irradiation, the antibacterial activity of the platform could be enhanced greatly by LT–PTT effect of CuS–BSA nanoparticles. In vitro and in vivo results both confirmed that the antibacterial efficacy of the synergistic therapeutic strategy was improved greatly with complete bacterial removal. Overall, this platform has posed a potential strategy to reduce the development of drug resistance and improve patient compliance.

In situ injectable NIR-responsive supramolecular hydrogels encapsulating ROS-triggered chain-breakage prodrug micelles and hydrophilic Fe3O4 nanoparticles for enhanced synergistic chemo-photothermal therapy.

Efficient synergistic therapeutic strategies for tumors with high specificity and sensitivity remain a major challenge. An injectable near-infrared (NIR)-responsive supramolecular hydrogel was prepared via host-guest interactions between conjugated poly(N-phenylglycine)-poly(ethylene glycol) (PNPG-PEG) and α-cyclodextrin. A reactive oxygen species (ROS)-triggered chain-breakage prodrug was composed of a thioketal (TK) linkage of methoxy poly(ethylene glycol) (mPEG) and doxorubicin (DOX). The resulting amphiphilic conjugate mPEG-TK-DOX can self-assemble into prodrug micelles. PEG/poly(etherimide) (PEI)@Fe3O4 nanoparticles (PEG/PEI@Fe3O4 NPs) were prepared using a thermal decomposition method. The prodrug micelles and PEG/PEI@Fe3O4 NPs can be well dispersed into the hydrogel system. In a tumor micro-acid environment, PEG/PEI@Fe3O4 NPs catalyze the decomposition of H2O2 to highly toxic ˙OH via a Fenton reaction to induce the breakage of ROS-responsive TK bonds for the dissociation of micelles and the continuous release of DOX. PEG/PEI@Fe3O4 NPs can also generate an NIR-thermal effect and enhance the photothermal therapy. Notably, by combining with controllable photothermal therapy, the in situ composite hydrogel system shows enhanced synergistic chemo-photothermal therapy for tumors and almost complete in vitro and in vivo tumor suppression, providing a promising synergistic tumor treatment strategy.

Engineering magnetotactic bacteria MVs to synergize chemotherapy, ferroptosis and immunotherapy for augmented antitumor therapy.

One main obstacle to targeted cancer therapies is the immunosuppressive tumor microenvironment, which can facilitate tumor growth and induce resistance to antitumor treatments. Recent studies have indicated that treatment combined with immunotherapy often yields a better prognosis than monotherapy. Bacterial membrane vesicles (MVs), nanostructures released from the membrane of bacteria, can be used as natural nanocarriers for drug delivery and stimulate an immune response because of their immunogenicity. Inspired by the development of synergistic therapeutic strategies, we herein propose a novel nanovaccine-based platform to achieve chemotherapy, ferroptosis therapy, and immunotherapy simultaneously. By simply culturing magnetotactic bacteria in the medium with doxorubicin (DOX) and then extracting specialized MVs (BMVs), BMV@DOX, which are membrane vesicles containing iron ions and DOX, were obtained. We confirmed that in BMV@DOX, the BMV component can stimulate the innate immune system, DOX acts as the chemotherapeutic agent and iron ions will induce ferroptosis. Furthermore, BMV@DOX vesicles modified with DSPE-PEG-cRGD peptides (T-BMV@DOX) have minimized systemic toxicity and increased tumor-specificity. We demonstrated that the smart MVs-based nanovaccine system not only showed superior performance in the treatment of 4T1 breast cancer but also effectively restrained the growth of drug-resistant MCF-7/ADR tumors in mice. Moreover, the nanovaccine could abrogate in vivo lung metastasis of tumor cells in a 4T1-Luc cell induced-lung breast cancer metastasis model. Collectively, the MVs-based nanoplatform offers an alternative promise for surmounting the limitations of monotherapy and may deserve further study for application in synergistic cancer therapy.

Combined inhibition of topoisomerase I and poly(ADP-ribose) polymerase: A synergistic therapeutic strategy for glioblastoma with phosphatase and tensin homolog deficiency.

Deletions or loss-of-function mutations in phosphatase and tensin homolog (PTEN) are common in glioblastoma (GBM) and have been associated with defective DNA damage repair. Here we investigated whether PTEN deficiency presents a vulnerability to a simultaneous induction of DNA damage and suppression of repair mechanisms by combining topoisomerase I (TOP1) and PARP inhibitors. Patient-derived GBM cells and isogenic PTEN-null and PTEN-WT glioma cells were treated with LMP400 (Indotecan), a novel non-camptothecin TOP1 inhibitor alone and in combination with a PARP inhibitor, Olaparib or Niraparib. RNAseq analysis was performed to identify treatment-induced dysregulated pathways. We found that GBM cells lacking PTEN expression are highly sensitive to LMP400; however, rescue of the PTEN expression reduces sensitivity to the treatment. Combining LMP400 with Niraparib leads to synergistic cytotoxicity by inducing G2/M arrest, DNA damage, suppression of homologous recombination-related proteins, and activation of caspase 3/7 activity significantly more in PTEN-null cells compared to PTEN-WT cells. LMP400 and Niraparib are not affected by ABCB1 and ABCG2, the major ATP-Binding Cassette (ABC) drug efflux transporters expressed at the blood-brain barrier (BBB), thus suggesting BBB penetration which is a prerequisite for potential brain tumor treatment. Animal studies confirmed both an anti-glioma effect and sufficient BBB penetration to prolong survival of mice treated with the drug combination. Our findings provide a proof of concept for the combined treatment with LMP400 and Niraparib in a subset of GBM patients with PTEN deficiency.

Cryo-Shocked Cancer Cells as an Oncolytic Adenovirus Reservoir for Glioblastoma Immunotherapy

Glioblastoma is the most common type of primary brain tumor, which has a high recurrence rate and a high mortality rate. Immunotherapy shows promise in cancer therapy due to its capacity to manipulate the immune system to attack tumor cells with less toxic and durable immune responses. However, the low immunogenicity and limited immune cell infiltration in a glioblastoma lead to a weakened antitumor immune response, resulting in suboptimal therapeutic efficacy. A compelling solution is provided by oncolytic adenovirus (OAs), which can selectively replicate within tumor cells while simultaneously promoting antitumor immunity. Herein, we constructed an oncolytic adenovirus reservoir (OAR) by shocking OA-loaded tumor cells in liquid nitrogen to eliminate proliferation and pathogenicity. OARs showed sustained OAs release and effectively lysed tumor cells in vitro and in vivo. In a mouse intracranial glioblastoma model, OARs could efficiently induce dendritic cells' maturation, facilitate the tumor recruitment, and promote the infiltration of cytotoxic effector T lymphocytes via a single treatment, resulting in specific antitumor immune responses and long-term animal survival. Taken together, these results demonstrated that OAR is a promising synergistic therapeutic strategy for treating glioblastoma.

Synergistic Therapeutic Effects of Low Dose Decitabine and NY-ESO-1 Specific TCR-T Cells for the Colorectal Cancer With Microsatellite Stability.

Patients of colorectal cancer (CRC) with microsatellite stability (MSS) show poor clinical response and little beneficial result from the immune-checkpoint inhibitors, due to the ‘cold’ tumor microenvironment. Meanwhile, decitabine can drive the ‘cold’ microenvironment towards ‘hot’ in multiple ways, such as upregulating the tumor associated antigen (TAA) and human leukocyte antigen (HLA) molecular. NY-ESO-1, one of the most important TAAs, can be observably induced in tumors by low dose decitabine, and present itself as ideal targets for antigen specific T cell receptor engineered T (TCR-T) cells. We innovatively used a synergistic tactic, combining decitabine and NY-ESO-1 specific TCR-T cells, for fighting the MSS CRC. Firstly, we confirmed the lysing effect of the NY-ESO-1 TCR-T cells on the NY-ESO-1+ and HLA-A2+ cells in vitro and in vivo. In A375 tumor-bearing mice, the results showed that NY-ESO-1 TCR-T cell therapy could inhibit A375 tumor growth and prolonged the survival time. Furthermore, the synergistic effect of decitabine and NY-ESO-1 TCR-T cells was shown to induce an even higher percentage of tumor cells being lysed in vitro than other control groups, and more potent tumor inhibition and longer survival time were observed in vivo. The innovative synergistic therapeutic strategy of decitabine and TCR-T cells for the CRC with MSS may be also effective in the treatment of other epithelial malignancies. Decitabine may likewise be adopted in combination with other cellular immunotherapies.

Synergistic activity of PARP inhibitors (PARPi) in combination with standard chemotherapy (CTx) in leiomyosarcoma.

11560 Background: Leiomyosarcomas (LMS) are genetically heterogeneous tumors that arise from smooth muscle. Currently, the mainstay of systemic treatment for patients with advanced/metastatic disease is doxorubicin (Dox) based CTx. Several genomic analyses of LMS reveal defects in homologous recombination (HR) DNA repair pathway in about half of patients, consistent with a druggable “BRCAness” phenotype. Thus, we sought to determine which combinations of standard CTx and PARPi might be synergistic promising therapeutic strategies for LMS. Methods: Dox, Docetaxel (Doc), Temozolomide (Tmz) were evaluated in combination with PARPi (Olaparib [Ola], Niraparib [Nira] and Talazoparib [Tala]) at 12 different drug concentrations. Four LMS cell lines of different origins (gynecological - GY, abdominal - A, extremity - E) were tested in a high throughput manner. All drug concentrations were chosen according to EC50. Cells were incubated with each combination for 7 days. Viability was assessed by ATPlite Luminescence Assay System.Evaluation of drug combination effect was performed using a Bliss synergy score. This system quantifies the degree of synergy as multiplicative effect of single drugs as if they acted independently. With a synergy score of -5 to 5, the interaction between two drugs is considered as additive; <-5 antagonistic and > 5 synergistic, and therefore a promising combination. Results: Anticancer activity, ranging from additive to synergistic was seen with all combinations. Results were consistent among all cell lines, independent of site of cell line origin (Table) Most synergistic combination in the majority of LMS cell lines were Dox or Tmz when combined with Tala, reaching up to 15 % and 27% above Bliss respectively. In contrast, Doc showed only additive effect with all analyzed PARPi. Conclusions: The data suggest that the combination of Dox or Tmz with PARPi may represent promising treatment options for LMS patients. Recent clinical studies support this notion in uterine LMS. Importantly these results suggest that such approach may be extended to all sites of LMS. Pre-clinical studies are underway to identify the most promising combinations for future clinical trial design. [Table: see text]

Targeting CDCP1 gene transcription coactivated by BRD4 and CBP/p300 in castration-resistant prostate cancer.

CUB domain-containing protein 1 (CDCP1), a transmembrane protein with tumor pro-metastatic activity, is highly expressed in late-stage and castrate-resistant prostate cancer (CRPC). However, the molecular mechanism driving CDCP1 overexpression in CRPC progress remains elusive. Here we report that transcription cofactors BRD4 and CBP/p300 co-regulate transcriptional expression of CDCP1 in CRPC tumorigenesis. In contrast to androgen receptor (AR) in CRPC, increased expression of BRD4 and CBP/p300 is strongly correlated with CDCP1 gene amplification. Combined knockdown or dual-inhibition of BRD4 and CBP/p300 down-regulated CDCP1 transcription and downstream PI3K/AKT and/or SRC/MAPK signaling pathways in CRPC cells much more so than single-protein perturbation. Our biochemical and structural analyses further showed that NEO2734, a dual-inhibitor targeting BRD4 and p300 bromodomains exhibits greater efficacy than single inhibitors for BRD4 or CBP/p300 in suppressing CDCP1 transcriptional expression and its downstream signaling pathways in CRPC cell proliferation and metastasis. Our study illustrates that targeting CDCP1 through dual-inhibition of BRD4 and CBP/p300 represents a synergistic therapeutic strategy for new treatment of CRPC.