Amplified antitumor efficacy by a targeted drug retention and chemosensitization strategy-based "combo" nanoagent together with PD-L1 blockade in reversing multidrug resistance

Innovative Nanomedicine Delivery: Targeting Tumor Microenvironment to Defeat Drug Resistance

Nanodrug delivery systems have revolutionized tumor therapy like never before. By overcoming the complexity of the tumor microenvironment (TME) and bypassing drug resistance mechanisms, nanotechnology has shown great potential to improve drug efficacy and reduce toxic side effects. This review examines the impact of the TME on drug resistance and recent advances in nanomedicine delivery systems to overcome this challenge. Characteristics of the TME such as hypoxia, acidity, and high interstitial pressure significantly reduce the effectiveness of chemotherapy and radiotherapy, leading to increased drug resistance in tumor cells. Then, this review summarizes innovative nanocarrier designs for these microenvironmental features, including hypoxia-sensitive nanoparticles, pH-responsive carriers, and multifunctional nanosystems that enable targeted drug release and improved drug penetration and accumulation in tumors. By combining nanotechnology with therapeutic strategies, this review offers a novel perspective by focusing on the innovative design of nanocarriers that interact with the TME, a dimension often overlooked in similar reviews. We highlight the dual role of these nanocarriers in therapeutic delivery and TME modulation, emphasize their potential to overcome drug resistance, and look at future research directions.

NIR-responsive copper nanoliposome composites for cascaded ferrotherapy via ferroptosis actived ICD and IFN-γ released

Metallic biomaterials activate tumor ferroptosis by increasing oxidative stress, but their efficacy is severely limited in tumor microenvironment. Although interferon gamma (IFN-γ) can promote tumor ferroptosis sensitivity by inhibiting the antioxidant system and promoting lipid accumulation, this effect limited by the lack of IFN-γ accumulation in tumors. Herein, we report a near-infrared (NIR)-responsive HCuS nanocomposite (HCuS-PE@TSL-tlyp-1) that can stimulate immunogenic cell death (ICD)-mediated IFN-γ secretion through exogenous oxidative stress, thereby achieving cascaded ferrotherapy by mutually reinforcing ferroptosis and systemic immunity. Upon laser irradiation, the dissolution of the thermal coating, and the introduction of Cu ions and piperazine-erastin (PE) simultaneously induce oxidative stress by reactive oxygen species (ROS)/lipid peroxide (LPO) accumulation and deplete cystine-glutamate transporter (xCT)/GSH. The onset of oxidative stress-mediated ferroptosis is thus achieved, and ICD is triggered, significantly promoting cytotoxic T-cell (CTL) infiltration for IFN-γ secretion. Furthermore, IFN-γ induces immunogenic tumor ferroptosis by inhibiting xCT-antioxidant pathways and enhancing the ACSL4-fatty acid recruitment pathway, which further promotes sensitivity to ferroptosis in cells. These HCuS nanocomposites combined with aPD-L1 effectively in inhibiting tumor metastasis and recurrence. Importantly, these cascade ferrotherapy results broadens the application of HCuS biomaterials.

Cuproptosis: A novel therapeutic target for overcoming cancer drug resistance

Cuproptosis is a newly identified form of cell death driven by copper. Recently, the role of copper and copper triggered cell death in the pathogenesis of cancers have attracted attentions. Cuproptosis has garnered enormous interest in cancer research communities because of its great potential for cancer therapy. Copper-based treatment exerts an inhibiting role in tumor growth and may open the door for the treatment of chemotherapy-insensitive tumors. In this review, we provide a critical analysis on copper homeostasis and the role of copper dysregulation in the development and progression of cancers. Then the core molecular mechanisms of cuproptosis and its role in cancer is discussed, followed by summarizing the current understanding of copper-based agents (copper chelators, copper ionophores, and copper complexes-based dynamic therapy) for cancer treatment. Additionally, we summarize the emerging data on copper complexes-based agents and copper ionophores to subdue tumor chemotherapy resistance in different types of cancers. We also review the small-molecule compounds and nanoparticles (NPs) that may kill cancer cells by inducing cuproptosis, which will shed new light on the development of anticancer drugs through inducing cuproptosis in the future. Finally, the important concepts and pressing questions of cuproptosis in future research that should be focused on were discussed. This review article suggests that targeting cuproptosis could be a novel antitumor therapy and treatment strategy to overcome cancer drug resistance.

Progressing nanotechnology to improve targeted cancer treatment: overcoming hurdles in its clinical implementation

The use of nanotechnology has the potential to revolutionize the detection and treatment of cancer. Developments in protein engineering and materials science have led to the emergence of new nanoscale targeting techniques, which offer renewed hope for cancer patients. While several nanocarriers for medicinal purposes have been approved for human trials, only a few have been authorized for clinical use in targeting cancer cells. In this review, we analyze some of the authorized formulations and discuss the challenges of translating findings from the lab to the clinic. This study highlights the various nanocarriers and compounds that can be used for selective tumor targeting and the inherent difficulties in cancer therapy. Nanotechnology provides a promising platform for improving cancer detection and treatment in the future, but further research is needed to overcome the current limitations in clinical translation.

Copper in cancer: From pathogenesis to therapy

One of the basic trace elements for the structure and metabolism of human tissue is copper. However, as a heavy metal, excessive intake or abnormal accumulation of copper in the body can cause inevitable damage to the organism because copper can result in direct injury to various cell components or disruption of the redox balance, eventually leading to cell death. Interestingly, a growing body of research reports that diverse cancers have raised serum and tumor copper levels. Tumor cells depend on more copper for their metabolism than normal cells, and a decrease in copper or copper overload can have a detrimental effect on tumor cells. New modalities for identifying and characterizing copper-dependent signals offer translational opportunities for tumor therapy, but their mechanisms remain unclear. Therefore, this article summarizes what we currently know about the correlation between copper and cancer and describes the characteristics of copper metabolism in tumor cells and the prospective application of copper-derived therapeutics.

Peptide Supramolecular Assembly-Instructed In Situ Self-Aggregation for Stratified Targeting Sonodynamic Therapy Enhancement of AIE Luminogens

The emergence of aggregation-induced emission luminogens (AIEgens) has attracted substantial scientific attention. However, their antitumor efficacy in photodynamic therapy (PDT) is significantly restricted by the poor water solubility and limited treatment depth. Therefore, a novel AIEgens-involved therapeutic platform with good permeability and bioavailability is urgently required. Herein, supramolecular chemistry is combined with the AIEgen bis-pyrene (BP) to construct a peptide-AIEgen hybrid nanosystem (PAHN). After intravenous injection, the versatile nanoplatform not only improved the hydrophilicity of BP but also achieved stratified targeting from tumor to mitochondrial and induced mitochondrial dysfunction, thus activating caspase-3 upregulation. Then, sonodynamic therapy (SDT), an alternative modality with high tissue penetrability, is performed to evoke reactive oxygen species (ROS) generation for BP. More importantly, since the hydrophilic shell is separated from the nanosystem by the specific cleavage of caspase-3, the resulting decrease in hydrophilicity induced tight self-aggregation of PAHN residues in situ, further allowing more absorbed energy to be used for ROS generation under ultrasound irradiation and enhancing SDT efficacy. Moreover, severe oxidative stress resulting from ROS imbalance in the mitochondria initiates the immunogenic cell death process, thus evoking antitumor immunogenicity. This PAHN provides prospective ideas into AIE-involved antitumor therapy and design of peptide-AIEgens hybrids.

Tumor-penetrating nanoplatform with ultrasound "unlocking" for cascade synergistic therapy and visual feedback under hypoxia

BACKGROUND

Combined therapy based on the effects of cascade reactions of nanoplatforms to combat specific solid tumor microenvironments is considered a cancer treatment strategy with transformative clinical value. Unfortunately, an insufficient O₂ supply and the lack of a visual indication hinder further applications of most nanoplatforms for solid tumor therapy.

RESULTS

A visualizable nanoplatform of liposome nanoparticles loaded with GOD, H(Gd), and PFP and grafted with the peptide tLyP-1, named _tLyP-1H(Gd)-GOD@PFP, was constructed. The double-domain peptide tLyP-1 was used to specifically target and penetrate the tumor cells; then, US imaging, starvation therapy and sonodynamic therapy (SDT) were then achieved by the ultrasound (US)-activated cavitation effect under the guidance of MR/PA imaging. GOD not only deprived the glucose for starvation therapy but also produced H₂O₂, which in coordination with ¹O₂ produced by H(Gd), enable the effects of SDT to achieve a synergistic therapeutic effect. Moreover, the synergistic therapy was enhanced by O₂ from PFP and low-intensity focused ultrasound (LIFU)-accelerated redox effects of the GOD. The present study demonstrated that the nanoplatform could generate a 3.3-fold increase in ROS, produce a 1.5-fold increase in the maximum rate of redox reactions and a 2.3-fold increase in the O₂ supply in vitro, and achieve significant tumor inhibition in vivo.

CONCLUSION

We present a visualizable nanoplatform with tumor-penetrating ability that can be unlocked by US to overcome the current treatment problems by improving the controllability of the O₂ supply, which ultimately synergistically enhanced cascade therapy.

Stimuli-responsive nanoassemblies for targeted delivery against tumor and its microenvironment

Despite the emergence of various cancer treatments, such as surgery, chemotherapy, radiotherapy, and immunotherapy, their use remains restricted owing to their limited tumor elimination efficacy and side effects. The use of nanoassemblies as delivery systems in nanomedicine for tumor diagnosis and therapy is flourishing. These nanoassemblies can be designed to have various shapes, sizes, and surface charges to meet the requirements of different applications. It is crucial for nanoassemblies to have enhanced delivery of payloads while inducing minimal to no toxicity to healthy tissues. In this review, stimuli-responsive nanoassemblies capable of combating the tumor microenvironment (TME) are discussed. First, various TME characteristics, such as hypoxia, oxidoreduction, adenosine triphosphate (ATP) elevation, and acidic TME, are described. Subsequently, the unique characteristics of the vascular and stromal TME are differentiated, and multiple barriers that have to be overcome are discussed. Furthermore, strategies to overcome these barriers for successful drug delivery to the targeted site are reviewed and summarized. In conclusion, the possible challenges and prospects of using these nanoassemblies for tumor-targeted delivery are discussed. This review aims at inspiring researchers to develop stimuli-responsive nanoassemblies for tumor-targeted delivery for clinical applications.

Nanodrug regulates lactic acid metabolism to reprogram the immunosuppressive tumor microenvironment for enhanced cancer immunotherapy

A majority of cancers fail to respond to immunotherapy due to the immunosuppressive tumor microenvironment (TME), and metabolic regulation of the TME has been a promising strategy to improve immunotherapy. Lactate is a key metabolic player in tumor immune response since its excess secretion aggravates tumor immune escape by favoring the polarization of tumor-associated macrophages (TAMs) to an immunosuppressive phenotype meanwhile impeding the tumor infiltration of the cytotoxic T lymphocyte. Here, we proposed a metabolic reprogramming mechanism to ameliorate tumor immunosuppression by using lonidamine and syrosingopine incorporated liposomes (L@S/L) to regulate lactate production and efflux. Concretely, lonidamine reduced lactate production by affecting the glycolytic metabolic pathway while syrosingopine decreased lactate efflux by inhibiting the key protein expression of the lactate transporter MCT-4. Consequently, both the drugs synergistically normalize the pH of the TME to overcome the tumor immunosuppressive microenvironment. In vivo studies demonstrated that the decreased extracellular lactate preferentially polarized TAMs to the M1 phenotype, simultaneously increased the proportion of NK cells and reduced the number of Treg cells. These results validated an efficient tumor immunotherapy in the breast cancer model. This new strategy of lactic acid metabolism regulation is proposed to operate in concert with immune modulation in the TME, which shows great potential for immunotherapy of immunologically "cold" tumors.

Preparation and application of pH-responsive drug delivery systems

Microenvironment-responsive drug delivery systems (DDSs) can achieve targeted drug delivery, reduce drug side effects and improve drug efficacies. Among them, pH-responsive DDSs have gained popularity since the pH in the diseased tissues such as cancer, bacterial infection and inflammation differs from a physiological pH of 7.4 and this difference could be harnessed for DDSs to release encapsulated drugs specifically to these diseased tissues. A variety of synthetic approaches have been developed to prepare pH-sensitive DDSs, including introduction of a variety of pH-sensitive chemical bonds or protonated/deprotonated chemical groups. A myriad of nano DDSs have been explored to be pH-responsive, including liposomes, micelles, hydrogels, dendritic macromolecules and organic-inorganic hybrid nanoparticles, and micron level microspheres. The prodrugs from drug-loaded pH-sensitive nano DDSs have been applied in research on anticancer therapy and diagnosis of cancer, inflammation, antibacterial infection, and neurological diseases. We have systematically summarized synthesis strategies of pH-stimulating DDSs, illustrated commonly used and recently developed nanocarriers for these DDSs and covered their potential in different biomedical applications, which may spark new ideas for the development and application of pH-sensitive nano DDSs.

Nano-Codelivery of Temozolomide and siPD-L1 to Reprogram the Drug-Resistant and Immunosuppressive Microenvironment in Orthotopic Glioblastoma

Glioblastoma (GBM) is an invasive cancer with high mortality in central nervous system. Resistance to temozolomide (TMZ) and immunosuppressive microenvironment lead to low outcome of the standardized treatment for GBM. In this study, a 2-deoxy-d-glucose modified lipid polymer nanoparticle loaded with TMZ and siPD-L1 (TMZ/siPD-L1@GLPN/dsb) was prepared to reprogram the TMZ-resistant and immunosuppressive microenvironment in orthotopic GBM. TMZ/siPD-L1@GLPN/dsb simultaneously delivered a large amount of TMZ and siPD-L1 to the deep area of the orthotopic TMZ-resistant GBM tissue. By inhibiting PD-L1 protein expression, TMZ/siPD-L1@GLPN/dsb markedly augmented the percentage of CD3⁺CD8⁺IFN-γ⁺ cells (T_eff cells) and reduced the percentage of CD4⁺CD25⁺FoxP3⁺ cells (T_reg cells) in orthotopic TMZ-resistant GBM tissue, which enhanced T-cell mediated cytotoxicity on orthotopic TMZ-resistant GBM. Moreover, TMZ/siPD-L1@GLPN/dsb obviously augmented the sensitivity of orthotopic TMZ-resistant GBM to TMZ through decreasing the protein expression of O⁶-methyl-guanine-DNA methyltransferase (MGMT) in TMZ-resistant GBM cells. Thus, TMZ/siPD-L1@GLPN/dsb markedly restrained the growth of orthotopic TMZ-resistant GBM and extended the survival time of orthotopic GBM rats through reversing a TMZ-resistant and immunosuppressive microenvironment. TMZ/siPD-L1@GLPN/dsb shows potential application to treat orthotopic TMZ-resistant GBM.

Synergistic photothermal-photodynamic-chemotherapy toward breast cancer based on a liposome-coated core-shell AuNS@NMOFs nanocomposite encapsulated with gambogic acid

A multifunctional nanoplatform with core–shell structure was constructed in one-pot for the synergistic photothermal, photodynamic, and chemotherapy against breast cancer. In the presence of gambogic acid (GA) as the heat-shock protein 90 (HSP90) inhibitor and the gold nanostars (AuNS) as the photothermal reagent, the assembly of Zr⁴⁺ with tetrakis (4-carboxyphenyl) porphyrin (TCPP) gave rise to the nanocomposite AuNS@ZrTCPP-GA (AZG), which in turn, further coated with PEGylated liposome (LP) to enhance the stability and biocompatibility, and consequently the antitumor effect of the particle. Upon cellular uptake, the nanoscale metal − organic framework (NMOF) of ZrTCPP in the resulted AuNS@ZrTCPP-GA@LP (AZGL) could be slowly degraded in the weak acidic tumor microenvironment to release AuNS, Zr⁴⁺, TCPP, and GA to exert the synergistic treatment of tumors via the combination of AuNS-mediated mild photothermal therapy (PTT) and TCPP-mediated photodynamic therapy (PDT). The introduction of GA serves to reduce the thermal resistance of the cell to re-sensitize PTT and the constructed nanoplatform demonstrated remarkable anti-tumor activity in vitro and in vivo. Our work highlights a facile strategy to prepare a pH-dissociable nanoplatform for the effective synergistic treatment of breast cancer.

Activatable “Matryoshka” nanosystem delivery NgBR siRNA and control drug release for stepwise therapy and evaluate drug resistance cancer

Drug resistance is always a challenge in conquering breast cancer clinically. Recognition of drug resistance and enhancing the sensitivity of the tumor to chemotherapy is urgent. Herein, a dual-responsive multi-function “Matryoshka" nanosystem is designed, it activates in the tumor microenvironment, decomposes layer by layer, and release gene and drug in sequence. The cell is re-educated by NgBR siRNA first to regain the chemosensitivity through regulating the Akt pathway and inhibit ERα activation, then the drugs loaded in the core are controlled released to killing cells. Carbonized polymer dots are loaded into the nanosystem as an efficient bioimaging probe, due to the GE11 modification, the nanosystem can be a seeker to recognize and evaluate drug-resistance tumors by photoacoustic imaging. In the tumor-bearing mouse, the novel nanosystem firstly enhances the sensitivity to chemotherapy by knockdown NgBR, inducing a much higher reduction in NgBR up to 52.09%, then effectively inhibiting tumor growth by chemotherapy, tumor growth in nude mouse was inhibited by 70.22%. The nanosystem also can inhibit metastasis, prolong survival time, and evaluate tumor drug resistance by real-time imaging. Overall, based on regulating the key molecules of drug resistance, we created visualization nanotechnology and formatted new comprehensive plans with high bio-safety for tumor diagnosis and treatment, providing a personalized strategy to overcome drug resistance clinically.

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Knockdown NgBR regulate the Akt pathway and inhibit ERα activate, enhance the sensitivity of chemotherapy.

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Knockdown of NgBR inhibits metastasis and prolongs survival.

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Nanosystem can evaluate drug resistance and kill tumors at the same time.

Immunomodulatory potential of natural products from herbal medicines as immune checkpoints inhibitors: Helping to fight against cancer via multiple targets

Immunotherapy sheds new light to cancer treatment and is satisfied by cancer patients. However, immunotoxicity, single‐source antibodies, and single‐targeting stratege are potential challenges to the success of cancer immunotherapy. A huge number of promising lead compounds for cancer treatment are of natural origin from herbal medicines. The application of natural products from herbal medicines that have immunomodulatory properties could alter the landscape of immunotherapy drastically. The present study summarizes current medication for cancer immunotherapy and discusses the potential chemicals from herbal medicines as immune checkpoint inhibitors that have a broad range of immunomodulatory effects. Therefore, this review provides valuable insights into the efficacy and mechanism of actions of cancer immunotherapies, including natural products and combined treatment with immune checkpoint inhibitors, which could confer an improved clinical outcome for cancer treatment.