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A photosensitive platinum(IV) prodrug (UVA-Pt2) was attached to a biodegradable polymer (PE, methoxyl-poly(ethylene glycol)-block-poly(lactide-co-2-methyl-2-carboxyl-propylene carbonate-ethanol amine)) and then the conjugate was self-assembled to micelles (NP-UVA-Pt2). In vitro MTT assay of NP-UVA-Pt2 demonstrated an improved cytotoxicity against SKOV-3 cells than that of cisplatin. Confocal laser scanning microscopy (CLSM) indicated that NP-UVA-Pt2 were endocytosed rather than internalized by passive diffusion, and thus, this process has nothing to do with copper transporter protein (Ctr1) as reported for cisplatin, which is closely related to drug resistance of Pt based drugs. Intracellular platinum content measured by ICP-MS result suggested that NP-UVA-Pt2 expressed higher platinum intracellular uptake than cisplatin. NP-UVA-Pt2 demonstrated fast and robust response to photo irradiation while the nanoparticles were stable in PBS at PH7.4 in the dark. The great drug efficacy of NP-UVA-Pt2 under UVA irradiation and the ineffectiveness in the dark makes NP-UVA-Pt2 an ideal light responsive on-demand drug delivery system. Hence, NP-UVA-Pt2 will be a promising platinum based drug in the near future. [ABSTRACT FROM AUTHOR]

Abstract: Cisplatin has long been the first line of treatment for a variety of solid tumors. However, poor pharmacokinetics and high incidences of resistance in the clinic have motivated the production of numerous alternative Pt-based anticancer species. Recently, photosensitive Pt(IV) complexes have garnered much interest because they offer a method of selective induction of active Pt(II) at the tumor site by UVA irradiation. Here, we report the first synthesis, in vitro and in vivo characterization of a novel series of photosensitive Pt(IV)–azide prodrugs and micellar nanoparticle formulations thereof. Upon mild UVA irradiation, both free Pt(IV) complexes and micellar nanoparticles rapidly released biologically active Pt(II), capable of binding to 5′-GMP, while remaining extremely stable in the dark. In vitro, uptake of photosensitive Pt(IV) prodrugs by ovarian cancer SKOV-3 cells was greatly enhanced with the micellar nanoparticles compared to their free prodrug analogs, as well as cisplatin and oxaliplatin. Increased cytotoxicity was observed upon UVA treatment, with up to a 13-fold enhancement over oxaliplatin for the micellar nanoparticles. In vivo bioavailability of micellar nanoparticles was enhanced ~10 fold over free Pt(IV) prodrugs. Importantly, micellar nanoparticles demonstrated significantly improved efficacy against H22 murine hepatocarcinoma, showing decreased systemic toxicity and increased tumor growth inhibition relative to small molecule drugs. These findings establish that photosensitive Pt(IV) complexes, specifically when formulated into micellar nanoparticles, have the potential to offer a robust platform for the controlled delivery and selective activation of Pt-based anticancer therapeutics. [Copyright &y& Elsevier]

Poor immunogenicity seriously hampers the broader implementation of antitumor immunotherapy. Enhanced immunogenicity capable of achieving greater antitumor immunity is urgently required. Here, a novel polymer that contains hydrophobic ferrocene (Fc) units and thioketal bonds in the main chain, which further delivered a prodrug of oxaliplatin and artesunate, i.e., Artoxplatin, to cancer cells is described. This polymer with Fc units in the nanoparticle can work as a polyigniter to spark the peroxide bonds in Artoxplatin and generate abundant reactive oxygen species (ROS) to kill cancers as nanobombig for cancer therapy. Moreover, ROS can trigger the breakdown of thioketal bonds in the polymer, resulting in the biodegradation of the polymer. Importantly, nanobombig can facilitate the maturation of dendritic cells and promote the activation of antitumor immunity, through the enhanced immunogenic cell death effect by ROS generated in situ. Furthermore, metabolomics analysis reveals a decrease in glutamine in nanobombig‐treated cancer cells, resulting in the upregulation of programmed death ligand 1 (PD‐L1). Consequently, it is further demonstrated enhanced tumor inhibitory effects when using nanobombig combined with anti‐PD‐L1 therapy. Overall, the nanosystem offers a rational design of an efficient chemo‐immunotherapy regimen to promote antitumor immunity by improving tumor immunogenicity, addressing the key challenges cancer immunotherapy faced. [ABSTRACT FROM AUTHOR]

Photodynamic therapy (PDT) has been widely employed in tumor treatment due to its effectiveness. However, the tumor hypoxic microenvironment which is caused by abnormal vasculature severely limits the efficacy of PDT. Furthermore, the abnormal vasculature has been implicated in the failure of immunotherapy. In this study, a novel nanoparticle denoted as Combo‐NP is introduced, composed of a biodegradable NIR II fluorescent pseudo‐conjugate polymer featuring disulfide bonds within its main chain, designated as TPA‐BD, and the vascular inhibitor Lenvatinib. Combo‐NP exhibits dual functionality by not only inducing cytotoxic reactive oxygen species (ROS) to directly eliminate tumor cells but also eliciting immunogenic cell death (ICD). This ICD response, in turn, initiates a robust cascade of immune reactions, thereby augmenting the generation of cytotoxic T lymphocytes (CTLs). In addition, Combo‐NP addresses the issue of tumor hypoxia by normalizing the tumor vasculature. This normalization process enhances the efficacy of PDT while concurrently fostering increased CTLs infiltration within the tumor microenvironment. These synergistic effects synergize to potentiate the photodynamic‐immunotherapeutic properties of the nanoparticles. Furthermore, when combined with anti‐programmed death‐ligand 1 (PD‐L1), they showcase notable inhibitory effects on tumor metastasis. The findings in this study introduce an innovative nanomedicine strategy aimed at triggering systemic anti‐tumor immune responses for the treatment of Uveal melanoma. [ABSTRACT FROM AUTHOR]

Tumor immunotherapy has emerged as one of the most promising clinical techniques to treat cancer tumors. Despite its clinical application, the cancerous immunosuppressive microenvironment limits the therapeutic efficiency of the treatment. To generate a stronger immunogenic therapeutic effect, herein, a platinum complex for chemotherapy and a BODIPY photosensitizer for photodynamic therapy are encapsulated into multimodal type II immunogenic cell death (ICD) induce nanoparticles. As the platinum complex and the photosensitizer are able to induce type II ICD, an exceptionally strong immune response is observed in triple‐negative breast cancer cells. While remaining stable and therefore poorly cytotoxic in the dark, the nanomaterial is found to quickly dissociate upon exposure to near‐infrared light, causing a multimodal mechanism of action in cancer cells as well as multicellular tumor spheroids through combined chemotherapy, photodynamic therapy, and immunotherapy. The nanoparticles are found to nearly fully eradicate a triple‐negative breast cancer tumor and therefore to strongly enhance the survival of tumor‐bearing mice models using low drug and light doses. [ABSTRACT FROM AUTHOR]

Despite the success of small interfering RNA (siRNA) in clinical settings and its potential value in human immunodeficiency virus (HIV) therapy, the rapid clearance and absence of precise delivery to target cells still hinder the therapeutic effect of siRNA. Herein, a new system, which can escape immune recognition, has HIV‐1 neutralizing capacity, and the ability to deliver siRNA specifically into HIV‐1‐infected cells, is constructed by functionalizing siRNA delivery lipid nanoparticles with the lymphocyte membrane and 12p1. The constructed system is shown to escape uptake by the mononuclear phagocyte system. The constructed system exhibits strong binding ability with gp120, thus displaying distinguished neutralizing breadth and potency. The constructed system neutralizes all tested HIV‐1 pseudotyped viruses with a geometric mean 80% inhibitory concentration (IC80) of 29.75 µg mL−1 and inhibits X4‐tropic HIV‐1 with an IC80 of 64.20 µg mL−1, and R5‐tropic HIV‐1 with an IC80 of 16.39 µg mL−1. The new system also specifically delivers siRNA into the cytoplasm of HIV‐1‐infected cells and exhibits evident gene silencing of tat and rev. Therefore, this new system can neutralize HIV‐1 and deliver siRNA selectively into HIV‐1‐infected cells and may be a promising therapeutic candidate for the precise therapy of HIV. [ABSTRACT FROM AUTHOR]

Over the last decades, a variety of metal complexes have been developed as chemotherapeutic agents. Despite the promising therapeutic prospects, the vast majority of these compounds suffer from low solubility, poor pharmacological properties, and most importantly poor tumor accumulation. To circumvent these limitations, herein, the incorporation of cytotoxic Ir(III) complexes and a variety of photosensitizers into polymeric gemini nanoparticles that selectively accumulate in the tumorous tissue and could be activated by near-infrared (NIR) light to exert an anticancer effect is reported. Upon exposure to light, the photosensitizer is able to generate singlet oxygen, triggering the rapid dissociation of the nanostructure and the activation of the Ir prodrug, thereby initiating a cascade of mitochondrial targeting and damage that ultimately leads to cell apoptosis. While selectively accumulating into tumorous tissue, the nanoparticles achieve almost complete eradication of the cisplatin-resistant cervical carcinoma tumor in vivo upon exposure to NIR irradiation. [ABSTRACT FROM AUTHOR]

Recent progress in studying copper‐dependent targets and pathways in the context of tumor treatment has provided new insights into therapeutic strategies of leveraging copper‐dependent disease vulnerabilities and pharmacological manipulation of intratumor copper transportation to improve chemotherapy. Here, we developed reactive oxygen species (ROS)‐sensitive nanoparticles loaded with copper chaperone inhibitor DC_AC50 and cisplatin(IV) prodrug. The released DC_AC50 can promote a remarkable accumulation of intracellular cisplatin and copper through inhibition of the Atox1‐ATPase pathways, thereby enhancing the chemotherapeutic effect of cisplatin and inducing significant ROS generation. Excessive ROS then elicits intense endoplasmic reticulin (ER) stress which facilitates the immunogenic cell death (ICD) spurring a sustained immune response. Our study suggests that nanoparticle‐mediated copper chaperone inhibition via DC_AC50 can restore the immunogenicity of tumor cells for enhanced chemotherapy and cancer immunotherapy. [ABSTRACT FROM AUTHOR]

Recent progress in studying copper‐dependent targets and pathways in the context of tumor treatment has provided new insights into therapeutic strategies of leveraging copper‐dependent disease vulnerabilities and pharmacological manipulation of intratumor copper transportation to improve chemotherapy. Here, we developed reactive oxygen species (ROS)‐sensitive nanoparticles loaded with copper chaperone inhibitor DC_AC50 and cisplatin(IV) prodrug. The released DC_AC50 can promote a remarkable accumulation of intracellular cisplatin and copper through inhibition of the Atox1‐ATPase pathways, thereby enhancing the chemotherapeutic effect of cisplatin and inducing significant ROS generation. Excessive ROS then elicits intense endoplasmic reticulin (ER) stress which facilitates the immunogenic cell death (ICD) spurring a sustained immune response. Our study suggests that nanoparticle‐mediated copper chaperone inhibition via DC_AC50 can restore the immunogenicity of tumor cells for enhanced chemotherapy and cancer immunotherapy. [ABSTRACT FROM AUTHOR]

Photodynamic therapy (PDT) has emerged as an attractive therapeutic approach which can elicit immunogenic cell death (ICD). However, current ICD inducers are still very limited as the representative ICD induces of photosensitizers can only evoke insufficient ICD to achieve unsatisfactory cancer immunotherapy. Herein, we demonstrated the use of a triple action cationic porphyrin-cisplatin conjugate (Pt-1) for drug delivery by a reactive oxygen species (ROS) sensitive polymer as nanoparticles (NP@Pt-1) for combined chemotherapy, PDT and immunotherapy. This unique triple action Pt-1 contains both chemotherapeutic Pt drugs and Porphyrin as a photosensitizer to generate ROS for PDT. Moreover, the ROS generated by Pt-1 can on the one hand degrade polymer carriers to release Pt-1 for chemotherapy and PDT. On the other hand, the ROS generated by Pt-1 subsequently triggered the ICD cascade for immunotherapy. Taken together, we demonstrated that NP@Pt-1 were the most effective and worked in a triple way. This study could provide us with new insight into the development of nanomedicine for chemotherapy, PDT as well as cancer immunotherapy. [ABSTRACT FROM AUTHOR]

These nanoparticles also display the ability of trapping free HIV-1 and inhibiting the gp120-induced bystander T cell death. B Precise siRNA Delivery b Precise delivery of siRNA into HIV-1-infected cells is realized by the lymphocyte membraneand 12p1-dual-functionalized nanoparticles. Lymphocyte Membrane- and 12p1-Dual-Functionalized Nanoparticles for Free HIV-1 Trapping and Precise siRNA Delivery into HIV-1-Infected Cells (Adv. Sci. 10/2023). [Extracted from the article]

External stimuli-responsive nanomedicine with desirable repetitive on-demand drug release character is postulated to greatly accommodate patients' flexible medication regime. To this object, light-activatable liposomes (Pt/Ce6-LP) integrated with both a Ce6 photodynamic component and a tetravalent platinum prodrug (Pt(IV)) chemotherapeutic component are engineered. This multifunctional system was rationally designed using unsaturated phospholipid to achieve repetitive on-demand drug release under discontinuous light irradiation, thus performing chemo-photodynamic therapy effect and immunopotentiation in hypoxic tumor. Furthermore, glutathione (GSH) consumption during transformation from Pt(IV) prodrug to Pt(II) can avoid depletion of reactive oxygen species (ROS) in photodynamic therapy (PDT). Note this positive feedback loop appears to remodel the redox balance of H 2 O 2 and GSH in tumors, alleviating the hypoxic tumor microenvironment. The alleviated hypoxia is found to be critical to the enhancement of PDT efficacy, reversal of cisplatin resistance in tumors, and polarization of tumor-associated macrophages (TAMs) to the immunocompetent M1-phynotype. Pt/Ce6-LP with light radiation demonstrates significant antitumor effect and persistent post-medication inhibition in patient-derived tumor xenograft model of hepatocellular carcinoma. A light-activatable liposome (Pt/Ce6-LP) was constructed to realize repetitive on-demand drug release and intensified PDT/chemotherapy on patient-derived tumor xenograft model of hepatocellular carcinoma. Pt/Ce6-LP with light irradiation overcame hypoxia-relative therapeutic resistance via a positive feedback loop and increased M1-TAMs populations to potentiate immune activity for hypoxic tumor treatment. Image 1 [ABSTRACT FROM AUTHOR]

Cell membrane coating nanotechnology, which endows nanoparticles with unique properties, displays excellent translational potential in cancer diagnosis and therapy. However, the preparation and evaluation of these cell membrane‐coated nanoparticles are based on cell lines and cell‐line‐based xenograft mouse models. The feasibility of cell membrane‐camouflaged nanomaterials is tested in a preclinical setting. Head and neck squamous cell carcinoma (HNSCC) patient‐derived tumor cell (PDTC) membranes are coated onto gelatin nanoparticles (GNPs) and the resulting PDTC@GNPs show efficient targeting to homotypic tumor cells and tissues in patient‐derived xenograft (PDX) models. When the donor‐derived cell membrane of PDTC@GNPs matched those of the host cells, significant targeting capability is observed. In contrast, mismatch between the donor and host results in weak targeting. Furthermore, it is demonstrated that autologous separation and administration of cellular membranes and anticancer cisplatin (Pt)‐loaded PDTC@GNPs, respectively, lead to almost complete tumor ablation in a subcutaneous model and effectively inhibit tumor recurrence in a postsurgery model. The work presented here reinforces the translation of these biomimetic nanoparticles for clinical applications and offers a simple, safe, and effective strategy for personalized cancer treatment. [ABSTRACT FROM AUTHOR]

Advanced staged high‐grade serous ovarian cancer (HGSOC) is the leading cause of gynecological cancer death in the developed world, with 5‐year survival rates of only 25–30% due to late‐stage diagnosis and the shortcomings of platinum‐based therapies. A Phase I clinical trial of a combination of free cisplatin and poly(ADP‐ribose) polymerase inhibitors (PARPis) showed therapeutic benefit for HGSOC. In this study, we address the challenge of resistance to platinum‐based therapy by developing a targeted delivery approach. Novel electrostatic layer‐by‐layer (LbL) liposomal nanoparticles (NPs) with a terminal hyaluronic acid layer that facilitates CD44 receptor targeting are designed for selective targeting of HGSOC cells; the liposomes can be formulated to contain both cisplatin and the PARPi drug within the liposomal core and bilayer. The therapeutic effectiveness of LbL NP‐encapsulated cisplatin and PARPi alone and in combination was compared with the corresponding free drugs in luciferase and CD44‐expressing OVCAR8 orthotopic xenografts in female nude mice. The NPs exhibited prolonged blood circulation half‐life, mechanistic staged drug release and targeted codelivery of the therapeutic agents to HGSOC cells. Moreover, compared to the free drugs, the NPs resulted in significantly reduced tumor metastasis, extended survival, and moderated systemic toxicity. [ABSTRACT FROM AUTHOR]