Combinational strategy for high-performance cancer chemotherapy

Exploring the role of m7G modification in Cancer: Mechanisms, regulatory proteins, and biomarker potential

The dysregulation of N(7)-methylguanosine (m7G) modification is increasingly recognized as a key factor in the pathogenesis of cancers. Aberrant expression of these regulatory proteins in various cancers, including lung, liver, and bladder cancers, suggests a universal role in tumorigenesis. Studies have established a strong correlation between the expression levels of m7G regulatory proteins, such as Methyltransferase like 1 (METTL1) and WD repeat domain 4 (WDR4), and clinical parameters including tumor stage, grade, and patient prognosis. For example, in hepatocellular carcinoma, high METTL1 expression is associated with advanced tumor stage and poor prognosis. Similarly, WDR4 overexpression in colorectal cancer correlates with increased tumor invasiveness and reduced patient survival. This correlation underscores the potential of these proteins as valuable biomarkers for cancer diagnosis and prognosis. Additionally, m7G modification regulatory proteins influence cancer progression by modulating the expression of target genes involved in critical biological processes, including cell proliferation, apoptosis, migration, and invasion. Their ability to regulate these processes highlights their significance in the intricate network of molecular interactions driving tumor development and metastasis. Given their pivotal role in cancer biology, m7G modification regulatory proteins are emerging as promising therapeutic targets. Targeting these proteins could offer a novel approach to disrupt the malignant behavior of cancer cells and enhance treatment outcomes. Furthermore, their diagnostic and prognostic value could aid in the early detection of cancer and the selection of appropriate therapeutic strategies, ultimately enhancing patient management and survival rates. This review aims to explore the mechanisms of action of RNA m7G modification regulatory proteins in tumors and their potential applications in cancer progression and treatment. By delving into the roles of these regulatory proteins, we intend to provide a theoretical foundation for the development of novel cancer treatment strategies.

Peptide-based supramolecular hydrogels and their biotherapeutic applications

In recent years, supramolecular hydrogels have made groundbreaking research progress in biomedical fields such as drug delivery, biosensing, imaging analysis, and tissue engineering. Peptides, with their unique characteristics of facile preparation, low immunogenicity and easy biodegradability, are commonly used as building blocks of supramolecular hydrogels. Peptide-based supramolecular hydrogels loaded with drugs, prepared via physical means or covalent crosslinking, exhibit unique three-dimensional network structures and strong water retention capacities. These properties enhance drug bioavailability and reduce side effects, enabling drug accumulation and responsive release at disease sites, significantly improving the therapeutic efficacy. Here, we review recent advancements in peptide-based supramolecular hydrogels and their biotherapeutic applications, including chemotherapy, photothermal therapy, photodynamic therapy, immunotherapy, gene therapy, antibacterial and anti-inflammatory treatments, and other biological applications. This review aims to provide new inspiration for the development of biomaterials in the therapeutic field and provide more personalized options for disease treatment. Additionally, challenges and limitations in this field are briefly discussed.

NIR-triggered arsenic-loaded layered double hydroxide-based films for localized thermal synergistic chemotherapy

Portal vein tumor thrombus (PVTT) formed by cancer cell invasion is a major cause of high mortality in hepatocellular carcinoma (HCC), and the formation of thrombus will be accelerated by bacterial colonization on the surface of the implant after surgery. In this work, Polypyrrole-coated arsenic-loaded layered double hydroxide films were in situ constructed on the nickel-titanium alloy for the efficient killing of tumour cells by thermo-therapeutic synergistic chemotherapy. The good near-infrared photothermal conversion ability of polypyrrole enables the sample surface temperature to be raised to about 51 °C at a low photothermal power (0.5 w/cm2), while the elevated temperature could further accelerate the release of drug arsenic. In addition, when NIR light is not applied, the polypyrrole coating also cleverly acts as a "barrier layer" to reduce the natural release of arsenic in normal tissues to avoid toxicity issues. In vivo and in vitro experiments have demonstrated that the platform exhibits excellent antitumor and antibacterial abilities. In contrast to the systemic toxicity issues associated with systemic circulation of nanotherapeutic drugs, this in situ functional film is expected to be used in localised interventions for precise drug delivery, and is also more suitable for surgical treatment scenarios in PVTT surgeries.

Deformable Smart DNA Nanomachine for Synergistic Intracellular Cancer-Related miRNAs Imaging and Chemo-Gene Therapy of Drug-Resistant Tumors

Diagnosis and treatment of tumor especially drug-resistant tumor remains a huge challenge, which requires intelligent nanomedicines with low toxic side effects and high efficacy. Herein, deformable smart DNA nanomachines are developed for synergistic intracellular cancer-related miRNAs imaging and chemo-gene therapy of drug-resistant tumors. The tetrahedral DNA framework (MA-TDNA) with fluorescence quenched component and five antennas is self-assembled first, and then DOX molecules are loaded on the MA-TDNAs followed by linking MUC1-aptamer and Mcl-1 siRNA to the antennas of MA-TDNA, so that the apt-MA-TDNA@DOX-siRNA (DNA nanomachines) is constructed. The DNA nanomachine can respond to two tumor-related miRNAs in vitro and in vivo, which can undergo intelligent miRNA-triggered opening of the framework, resulting in the "turn on" of the fluorescence for sensitively and specifically sensing intracellular miRNAs. Meanwhile, both miRNA-responded rapid release and pH-responded release of DOX are achieved for chemotherapy of tumor. In addition, the gene therapy of the DNA nanomachines is achieved due to the miRNA-specific capture and the RNase H triggered release of Mcl-1 siRNA. The DNA nanomachines intergrading both tumor imaging and chemo-gene therapy in single nanostructures realized efficient tumor-targeted, image-guided, and microenvironment-responsive tumor diagnosis and treatment, which provides a synergetic antitumor effect on drug-resistant tumor.

The recent advancements in protein nanoparticles for immunotherapy

In recent years, the advancement of nanoparticle-based immunotherapy has introduced an innovative strategy for combatting diseases. Compared with other types of nanoparticles, protein nanoparticles have obtained substantial attention owing to their remarkable biocompatibility, biodegradability, ease of modification, and finely designed spatial structures. Nature provides several protein nanoparticle platforms, including viral capsids, ferritin, and albumin, which hold significant potential for disease treatment. These naturally occurring protein nanoparticles not only serve as effective drug delivery platforms but also augment antigen delivery and targeting capabilities through techniques like genetic modification and covalent conjugation. Motivated by nature's originality and driven by progress in computational methodologies, scientists have crafted numerous protein nanoparticles with intricate assembly structures, showing significant potential in the development of multivalent vaccines. Consequently, both naturally occurring and de novo designed protein nanoparticles are anticipated to enhance the effectiveness of immunotherapy. This review consolidates the advancements in protein nanoparticles for immunotherapy across diseases including cancer and other diseases like influenza, pneumonia, and hepatitis.

Construction of 5-Fluorouracil and Gallium Corrole Conjugates for Enhanced Photodynamic Therapy

Molecular hybridization is a well-established strategy for developing new drugs. In the pursuit of promising photosensitizers (PSs) with enhanced photodynamic therapy (PDT) efficiency, a series of novel 5-fluorouracil (5FU) gallium corrole conjugates (1-Ga-4-Ga) were designed and synthesized by hybridizing a chemotherapeutic drug and PSs. Their photodynamic antitumor activity was also evaluated. The most active complex (2-Ga) possesses a low IC50 value of 0.185 μM and a phototoxic index of 541 against HepG2 cells. Additionally, the 5FU-gallium corrole conjugate (2-Ga) exhibited a synergistic increase in cytotoxicity under irradiation. Excitedly, treatment of HepG2 tumor-bearing mice with 2-Ga under irradiation could completely ablate tumors without harming normal tissues. 2-Ga-mediated PDT could disrupt mitochondrial function, cause cell cycle arrest in the sub-G1 phase, and activate the cell apoptosis pathway by upregulating the cleaved PARP expression and the Bax/Bcl-2 ratios. This work provides a useful strategy for the design of new corrole-based chemo-photodynamic therapy drugs.

Progress and application of lung-on-a-chip for lung cancer

Lung cancer is a malignant tumour with the highest incidence and mortality worldwide. Clinically effective therapy strategies are underutilized owing to the lack of efficient models for evaluating drug response. One of the main reasons for failure of anticancer drug therapy is development of drug resistance. Anticancer drugs face severe challenges such as poor biodistribution, restricted solubility, inadequate absorption, and drug accumulation. In recent years, "organ-on-a-chip" platforms, which can directly regulate the microenvironment of biomechanics, biochemistry and pathophysiology, have been developed rapidly and have shown great potential in clinical drug research. Lung-on-a-chip (LOC) is a new 3D model of bionic lungs with physiological functions created by micromachining technology on microfluidic chips. This approach may be able to partially replace animal and 2D cell culture models. To overcome drug resistance, LOC realizes personalized prediction of drug response by simulating the lung-related microenvironment in vitro, significantly enhancing therapeutic effectiveness, bioavailability, and pharmacokinetics while minimizing side effects. In this review, we present an overview of recent advances in the preparation of LOC and contrast it with earlier in vitro models. Finally, we describe recent advances in LOC. The combination of this technology with nanomedicine will provide an accurate and reliable treatment for preclinical evaluation.

Better together: nanoscale co-delivery systems of therapeutic agents for high-performance cancer therapy

Combination therapies can enhance the sensitivity of cancer to drugs, lower drug doses, and reduce side effects in cancer treatment. However, differences in the physicochemical properties and pharmacokinetics of different therapeutic agents limit their application. To avoid the above dilemma and achieve accurate control of the synergetic ratio, a nanoscale co-delivery system (NCDS) has emerged as a prospective tool for combined therapy in cancer treatment, which is increasingly being used to co-load different therapeutic agents. In this study, we have summarized the mechanisms of therapeutic agents in combination for cancer therapy, nanoscale carriers for co-delivery, drug-loading strategies, and controlled/targeted co-delivery systems, aiming to give a general picture of these powerful approaches for future NCDS research studies.

Supramolecular prodrug of SN38 based on endogenous albumin and SN38 prodrug modified with semaglutide side chain to improve the tumor distribution

To improve the biodistribution of the drug in the tumor, a supramolecular prodrug of SN38 was fabricated in situ between endogenous albumin and SN38 prodrug modified with semaglutide side chain. Firstly, SN38 was conjugated with semaglutide side chain and octadecanedioic acid via glycine linkers to obtain SI-Gly-SN38 and OA-Gly-SN38 prodrugs, respectively. Both SI-Gly-SN38 and OA-Gly-SN38 exhibited excellent stability in PBS for over 24 h. Due to the strong binding affinity of the semaglutide side chain with albumin, the plasma half-life of SI-Gly-SN38 was 2.7 times higher than that of OA-Gly-SN38. Furthermore, with addition of HSA, the fluorescence intensity of SI-Gly-SN38 was 4 times higher than that of OA-Gly-SN38, confirming its strong binding capability with HSA. MTT assay showed that the cytotoxicity of SI-Gly-SN38 and OA-Gly-SN38 was higher than that of Irinotecan. Even incubated with HSA, the SI-Gly-SN38 and OA-Gly-SN38 still maintained high cytotoxicity, indicating minimal influence of HSA on their cytotoxicity. In vivo pharmacokinetic studies demonstrated that the circulation half-life of SI-Gly-SN38 was twice that of OA-Gly-SN38. SI-Gly-SN38 exhibited significantly reduced accumulation in the lungs, being only 0.23 times that of OA-Gly-SN38. The release of free SN38 in the lungs from SI-Gly-SN38 was only 0.4 times that from OA-Gly-SN38 and Irinotecan. The SI-Gly-SN38 showed the highest accumulation in tumors. The tumor inhibition rate of SI-Gly-SN38 was 6.42% higher than that of OA-Gly-SN38, and 8.67% higher than that of Irinotecan, respectively. These results indicate that the supramolecular prodrug delivery system can be constructed between SI-Gly-SN38 and endogenous albumin, which improves drug biodistribution in vivo, enhances tumor accumulation, and plays a crucial role in tumor growth inhibition.

Nanocarrier-Integrated Microneedles: Divulging the Potential of Novel Frontiers for Fostering the Management of Skin Ailments

The various kinds of nanocarriers (NCs) have been explored for the delivery of therapeutics designed for the management of skin manifestations. The NCs are considered as one of the promising approaches for the skin delivery of therapeutics attributable to sustained release and enhanced skin penetration. Despite the extensive applications of the NCs, the challenges in their delivery via skin barrier (majorly stratum corneum) have persisted. To overcome all the challenges associated with the delivery of NCs, the microneedle (MN) technology has emerged as a beacon of hope. Programmable drug release, being painless, and its minimally invasive nature make it an intriguing strategy to circumvent the multiple challenges associated with the various drug delivery systems. The integration of positive traits of NCs and MNs boosts therapeutic effectiveness by evading stratum corneum, facilitating the delivery of NCs through the skin and enhancing their targeted delivery. This review discusses the barrier function of skin, the importance of MNs, the types of MNs, and the superiority of NC-loaded MNs. We highlighted the applications of NC-integrated MNs for the management of various skin ailments, combinational drug delivery, active targeting, in vivo imaging, and as theranostics. The clinical trials, patent portfolio, and marketed products of drug/NC-integrated MNs are covered. Finally, regulatory hurdles toward benchtop-to-bedside translation, along with promising prospects needed to scale up NC-integrated MN technology, have been deliberated. The current review is anticipated to deliver thoughtful visions to researchers, clinicians, and formulation scientists for the successful development of the MN-technology-based product by carefully optimizing all the formulation variables.

A Polymeric Nanoparticle to Co-Deliver Mitochondria-Targeting Peptides and Pt(IV) Prodrug: Toward High Loading Efficiency and Combination Efficacy

Developing combination chemotherapy systems with high drug loading efficiency at predetermined drug ratios to achieve a synergistic effect is important for cancer therapy. Herein, a polymeric dual-drug nanoparticle composed of a Pt(IV) prodrug derived from oxaliplatin and a mitochondria-targeting cytotoxic peptide is constructed through emulsion interfacial polymerization, which processes high drug loading efficiency and high biocompatibility. The depolymerization of polymeric dual-drug nanoparticle and the activation of Pt prodrug can be effectively triggered by the acidic tumor environment extracellularly and the high levels of glutathione intracellularly in cancer cells, respectively. The utilization of mitochondria-targeting peptide can inhibit ATP-dependent processes including drug efflux and DNA damage repair. This leads to increased accumulation of Pt-drugs within cancer cells. Eventually, the polymeric dual-drug nanoparticle demonstrates appreciable antitumor effects on both cell line derived and patient derived xenograft lung cancer model. It is highly anticipated that the polymeric dual-or multi-drug systems can be applied for combination chemotherapy to achieve enhanced anticancer activity and reduced side effects.

Developing a Copper(II) Isopropyl 2-Pyridyl Ketone Thiosemicarbazone Compound Based on the IB Subdomain of Human Serum Albumin-Indomethacin Complex: Inhibiting Tumor Growth by Remodeling the Tumor Microenvironment

To develop a next-generation metal agent and dual-agent multitargeted combination therapy, we developed a copper (Cu) compound based on the properties of the human serum albumin (HSA)-indomethacin (IND) complex to remodel the tumor microenvironment (TME). We optimized a series of Cu(II) isopropyl 2-pyridyl ketone thiosemicarbazone compounds to obtain a Cu(II) compound (C4) with significant cytotoxicity and then constructed an HSA-IND-C4 complex (HSA-IND-C4) delivery system. IND and C4 bind to the hydrophobic cavities of the IB and IIA domains of HSA, respectively. In vivo, the HSA-IND-C4 not only showed enhanced antitumor efficacy relative to C4 and C4 + IND but also improved their targeting ability and decreased their side effects. The antitumor mechanism of C4 + IND involved acting on the different components of the TME. IND inhibited tumor-related inflammation, while C4 not only induced apoptosis and autophagy of cancer cells but also inhibited tumor angiogenesis.

Reversing Anticancer Drug Resistance by Synergistic Combination of Chemotherapeutics and Membranolytic Antitumor β-Peptide Polymer

Multidrug resistance is the main obstacle to cancer chemotherapy. Overexpression of drug efflux pumps causes excessive drug efflux from cancer cells, ultimately leading to drug resistance. Hereby, we raise an effective strategy to overcome multidrug resistance using a synergistic combination of membranolytic antitumor β-peptide polymer and chemotherapy drugs. This membrane-active β-peptide polymer promotes the transmembrane transport of chemotherapeutic drugs by increasing membrane permeability and enhances the activity of chemotherapy drugs against multidrug-resistant cancer cells. As a proof-of-concept demonstration, the synergistic combination of β-peptide polymer and doxorubicin (DOX) is substantially more effective than DOX alone against drug-resistant cancer both in vitro and in vivo. Notably, the synergistic combination maintains a potent anticancer activity after continuous use. Collectively, this combination therapy using membrane lytic β-peptide polymer appears to be an effective strategy to reverse anticancer drug resistance.

Aggregation-Induced Emission Photosensitizer-Engineered Anticancer Nanomedicine for Synergistic Chemo/Chemodynamic/Photodynamic Therapy

Photodynamic therapy (PDT) with aggregation-induced emission (AIE) photosensitizers (PSs) is a promising therapeutic strategy to achieve better anticancer results. However, eradicating solid tumors completely by PDT alone can be difficult owing to the inherent drawbacks of this treatment, and the combination of PDT with other therapeutic modalities provides opportunities to achieve cooperative enhancement interactions among various treatments. Herein, this work presents the construction of a biocompatible nanocomposite, namely CaO2@DOX@ZIF@ASQ, featuring light-responsive reactive oxygen species (ROS) generation and tumor-targeting oxygen and hydrogen peroxide discharge, as well as controlled doxorubicin (DOX) and copper ion release, thus allowing the combined PDT/CT/CDT effect by AIE PS-enhanced PDT, DOX-based chemotherapy (CT), and copper-involved Fenton-like reaction-driven chemodynamic therapy (CDT). In vitro and in vivo studies verify that the generation of both ROS and O2 by this nanomedicine, stimulated by light, exhibits superior anticancer efficacy, alleviating tumor hypoxia and achieving synergistic PDT/CT/CDT therapeutic effect. This multifunctional nanomedicine remarkably suppresses the tumor growth with minimized systemic toxicity, providing a new strategy for constructing multimodal PDT/CT/CDT therapeutic systems to overcome hypoxia limitations, and potentially increase the antitumor efficacy at lower doses of PSs and chemotherapeutic drugs, thus minimizing potential toxicity to non-malignant tissues.

Enhanced Postsurgical Cancer Treatment Using Methacrylated Glycol Chitosan Hydrogel for Sustained DNA/Doxorubicin Delivery and Immunotherapy

Background: Cancer recurrence and metastasis are major contributors to treatment failure following tumor resection surgery. We developed a novel implantable drug delivery system utilizing glycol chitosan to address these issues. Glycol chitosan is a natural adjuvant, inducing dendritic cell activation to promote T helper 1 cell immune responses, macrophage activation, and cytokine production. Effective antigen production by dendritic cells initiates T-cell-mediated immune responses, aiding tumor growth control. Methods: In this study, we fabricated multifunctional methacrylated glycol chitosan (MGC) hydrogels with extended release of DNA/doxorubicin (DOX) complex for cancer immunotherapy. We constructed the resection model of breast cancer to verify the anticancer effects of MGC hydrogel with DNA/DOX complex. Results: This study demonstrated the potential of MGC hydrogel with extended release of DNA/DOX complex for local and efficient cancer therapy. The MGC hydrogel was implanted directly into the surgical site after tumor resection, activating tumor-related immune cells both locally and over a prolonged period of time through immune-reactive molecules. Conclusions: The MGC hydrogel effectively suppressed tumor recurrence and metastasis while enhancing immunotherapeutic efficacy and minimizing side effects. This biomaterial-based drug delivery system, combined with cancer immunotherapy, can substantial improve treatment outcomes and patient prognosis.

Association between genetic variants of transmembrane transporters and susceptibility to anthracycline-induced cardiotoxicity: Current understanding and existing evidence

Anthracyclines remain the cornerstone of numerous chemotherapeutic protocols, with beneficial effects against haematological malignancies and solid tumours. Unfortunately, the clinical usefulness of anthracyclines is compromised by the development of cardiotoxic side effects, leading to dose limitations or treatment discontinuation. There is no absolute linear correlation between the incidence of cardiotoxicity and the threshold dose, suggesting that genetic factors may modify the association between anthracyclines and cardiotoxicity risk. And the majority of single nucleotide polymorphisms (SNPs) associated with anthracycline pharmacogenomics were identified in the ATP-binding cassette (ABC) and solute carrier (SLC) transporters, generating increasing interest in the pharmacogenetic implications of their genetic variations for anthracycline-induced cardiotoxicity (AIC). This review focuses on the influence of SLC and ABC polymorphisms on AIC and highlights the prospects and clinical significance of pharmacogenetics for individualised preventive approaches.

Mitophagy-Mediated Tumor Dormancy Protects Cancer Cells from Chemotherapy

Despite obvious tumor shrinkage, relapse after chemotherapy remains a main cause of cancer-related mortality, indicating that a subpopulation of cancer cells acquires chemoresistance and lingers after treatment. However, the mechanism involved in the emergence of chemoresistant cells remains largely unknown. Here, we demonstrate that the degradation of mitochondria via autophagy leads to a dormant state in a subpopulation of cancer cells and confers on them resistance to lethal cisplatin (DDP) exposure. The surviving DDP-resistant cells (hereafter, DRCs) have a lower metabolic rate but a stronger potential malignant potential. In the absence of DDP, these DRCs exhibit an ever-increasing self-renewal ability and heightened tumorigenicity. The combination of chloroquine and DDP exerts potent tumor-suppressive effects. In summary, our findings illuminate the mechanism between mitophagy and tumor dormancy and prove that targeting mitophagy might be a promising approach for overcoming chemoresistance in head and neck squamous cell carcinoma (HNSCC).

Synthesis of Fe3O4core/MIL-100(Fe) shell nanocomposites for tumor chemo-ferroptosis combination therapy and MR imaging

The application of both chemotherapy and ferrotherapy together has shown great potential in increasing the effectiveness of cancer treatment. To achieve such a combination, we herein have synthesized Fe3O4core/MIL-100(Fe) shell nanocomposites (FM) that can be used for tumor chemo-ferroptosis combination therapy. In these nanocomposites, the anticancer drug 10-hydroxycamptothecin (HCPT) and iron ions could be co-delivered into tumors. On one hand, the released HCPT molecules can enter the cell nucleus and bind with DNA, resulting in induction of tumor cell apoptosis. On the other hand, the iron ions could react with H2O2leading to the production of ROS through the Fenton reaction, thereby triggering tumor cell ferroptosis. Consequently, a superior antitumor effect was achieved through the combination of the apoptosis and ferroptosis. Additionally, the Fe3O4core endowed FM with high performance for magnetic resonance imaging, which further provided novel avenues for imaging guidance therapy. Therefore, we anticipate that application of these nanocomposites could have great potential in the field of tumor therapy.

Molecular Design and Controlled Self-Assembly of Copolymers as Core-Shell-Corona Nanoparticles for Smarter Tumor Treatment

Copolymer-based core-shell-corona nanoparticles have attracted more interest for tumor chemotherapy, owing to their unique multifunctionality benefiting from their unique multilevel topological structure in comparison with the conventional core-shell ones. Here, the recent progress in such core-shell-corona nanoparticle-based drug delivery systems (DDSs) in tumor chemotherapy was reviewed, focusing on additive functionality of the shell layer for controlled drug release performance from the viewpoints of the molecular design and controlled self-assembly, such as stimuli-responsive gatekeepers, independent loading of active substances, and so on. Moreover, future perspectives have been prospected for smarter tumor treatment.

A Guanosine-Derived Antitumor Supramolecular Prodrug

The prodrug strategy for its potential to enhance the pharmacokinetic and/or pharmacodynamic properties of drugs, especially chemotherapeutic agents, has been widely recognized as an important means to improve therapeutic efficiency. Irinotecan's active metabolite, 7-ethyl-10-hydroxycamptothecin (SN38), a borate derivative, was incorporated into a G-quadruplex hydrogel (GB-SN38) by the ingenious and simple approach. Drug release does not depend on carboxylesterase, thus bypassing the side effects caused by ineffective activation, but specifically responds to the ROS-overexpressed tumor microenvironment by oxidative hydrolysis of borate ester that reduces serious systemic toxicity from nonspecific biodistribution of SN38. Comprehensive spectroscopy was used to define the structural and physicochemical characteristics of the drug-loaded hydrogel. The GB-SN38 hydrogel's high level of biosafety and notable tumor-suppressive properties were proven in in vitro and in vivo tests.

Cancer cell membrane-coated bacterial ghosts for highly efficient paclitaxel delivery against metastatic lung cancer

Chemotherapy is one of the major approaches for the treatment of metastatic lung cancer, although it is limited by the low tumor delivery efficacy of anticancer drugs. Bacterial therapy is emerging for cancer treatment due to its high immune stimulation effect; however, excessively generated immunogenicity will cause serious inflammatory response syndrome. Here, we prepared cancer cell membrane-coated liposomal paclitaxel-loaded bacterial ghosts (LP@BG@CCM) by layer-by-layer encapsulation for the treatment of metastatic lung cancer. The preparation processes were simple, only involving film formation, electroporation, and pore extrusion. LP@BG@CCM owned much higher 4T1 cancer cell toxicity than LP@BG due to its faster fusion with cancer cells. In the 4T1 breast cancer metastatic lung cancer mouse models, the remarkably higher lung targeting of intravenously injected LP@BG@CCM was observed with the almost normalized lung appearance, the reduced lung weight, the clear lung tissue structure, and the enhanced cancer cell apoptosis compared to its precursors. Moreover, several major immune factors were improved after administration of LP@BG@CCM, including the CD4+/CD8a+ T cells in the spleen and the TNF-α, IFN-γ, and IL-4 in the lung. LP@BG@CCM exhibits the optimal synergistic chemo-immunotherapy, which is a promising medication for the treatment of metastatic lung cancer.

Supramolecular self-assembled peptide-engineered nanofibers: A propitious proposition for cancer therapy

Cancer is a devastating disease that causes a substantial number of deaths worldwide. Current therapeutic interventions for cancer include chemotherapy, radiation therapy, or surgery. These conventional therapeutic approaches are associated with disadvantages such as multidrug resistance, destruction of healthy tissues, and tissue toxicity. Therefore, there is a paradigm shift in cancer management wherein nanomedicine-based novel therapeutic interventions are being explored to overcome the aforementioned disadvantages. Supramolecular self-assembled peptide nanofibers are emerging drug delivery vehicles that have gained much attention in cancer management owing to their biocompatibility, biodegradability, biomimetic property, stimuli-responsiveness, transformability, and inherent therapeutic property. Supramolecules form well-organized structures via non-covalent linkages, the intricate molecular arrangement helps to improve tissue permeation, pharmacokinetic profile and chemical stability of therapeutic agents while enabling targeted delivery and allowing efficient tumor imaging. In this review, we present fundamental aspects of peptide-based self-assembled nanofiber fabrication their applications in monotherapy/combinatorial chemo- and/or immuno-therapy to overcome multi-drug resistance. The role of self-assembled structures in targeted/stimuli-responsive (pH, enzyme and photo-responsive) drug delivery has been discussed along with the case studies. Further, recent advancements in peptide nanofibers in cancer diagnosis, imaging, gene therapy, and immune therapy along with regulatory obstacles towards clinical translation have been deliberated.

Polyprodrugs for tumor chemotherapy: from molecular structure to drug release performance

Polyprodrugs have been recognized as promising carrier-free drug delivery systems (DDSs) for tumor chemotherapy in recent years, showing distinct superiority in comparison with the conventional polymer prodrugs. In the present work, the structure-property relationship of polyprodrugs was explored from the perspective of molecular structure, by discussing the effects of the conjugations and linkers on their drug content and drug releasing performance, including drug releasing rate and drug releasing selectivity, as well as the anti-tumor performance of the released drugs. Moreover, the future challenges in the design of polyprodrug-based DDSs with high anti-tumor efficacy were also highlighted.

Aspect ratio-dependent dual-regulation of the tumor immune microenvironment against osteosarcoma by hydroxyapatite nanoparticles

Accumulating studies demonstrated that hydroxyapatite nanoparticles (HANPs) showed a selective anti-tumor effect, making them a good candidate for osteosarcoma (OS) treatment. However, the capacity of HANPs with different aspect ratios to regulate tumor immune microenvironment (TIM) was scarcely reported before. To explore it, the three HANPs with aspect ratios from 1.86 to 6.25 were prepared by wet chemical method. After a 24 or 72 h-exposure of OS UMR106 cells or macrophages to the nanoparticles, the tumor cells exhibited immunogenic cell death (ICD) indicated by the increased production of calreticulin (CRT), adenosine triphosphate (ATP) and high mobility group box 1 (HMGB1), and macrophages were activated with the release of pro-inflammatory cytokines. Next, the beneficial crosstalk between tumor cells and macrophages generated in the presence of HANPs for improved anti-tumor immunity activation. In the OS-bearing cognate rat model, HANPs inhibited OS growth, which was positively correlated with CRT and HMGB1 expression, and macrophage polarization in the tumor tissues. Additionally, HANPs promoted CD8+ T cell infiltration into the tumor and systemic dendritic cell maturation. Particularly, HANPs bearing the highest aspect ratio exhibited the strongest immunomodulatory and anti-tumor function. This study suggested the potential of HANPs to be a safe and effective drug-free nanomaterial to control the TIM for OS therapy. STATEMENT OF SIGNIFICANCE: Emerging studies demonstrated that hydroxyapatite nanoparticles (HANPs) inhibited tumor cell proliferation and tumor growth. However, the underlying anti-tumor mechanism still remains unclear, and the capacity of HANPs without any other additive to regulate tumor immune microenvironment (TIM) was scarcely reported before. Herein, we demonstrated that HANPs, in an aspect ratio-dependent manner, showed the potential to delay the growth of osteosarcoma (OS) and to regulate TIM by promoting the invasion of CD8+ T cells and F4/80+ macrophages, and inducing immunogenic cell death (ICD) in tumors. This work revealed the new molecular mechanism for HANPs against OS, and suggested HANPs might be a novel ICD inducer for OS treatment.

The Dawn of a New Era: Tumor-Targeting Boron Agents for Neutron Capture Therapy

Cancer is widely recognized as one of the most devastating diseases, necessitating the development of intelligent diagnostic techniques, targeted treatments, and early prognosis evaluation to ensure effective and personalized therapy. Conventional treatments, unfortunately, suffer from limitations and an increased risk of severe complications. In light of these challenges, boron neutron capture therapy (BNCT) has emerged as a promising approach for cancer treatment with unprecedented precision to selectively eliminate tumor cells. The distinctive and promising characteristics of BNCT hold the potential to revolutionize the field of oncology. However, the clinical application and advancement of BNCT technology face significant hindrance due to the inherent flaws and limited availability of current clinical drugs, which pose substantial obstacles to the practical implementation and continued progress of BNCT. Consequently, there is an urgent need to develop efficient boron agents with higher boron content and specific tumor-targeting properties. Researchers aim to address this need by integrating tumor-targeting strategies with BNCT, with the ultimate goal of establishing BNCT as an effective, readily available, and cutting-edge treatment modality for cancer. This review delves into the recent advancements in integrating tumor-targeting strategies with BNCT, focusing on the progress made in developing boron agents specifically designed for BNCT. By exploring the current state of BNCT and emphasizing the prospects of tumor-targeting boron agents, this review provides a comprehensive overview of the advancements in BNCT and highlights its potential as a transformative treatment option for cancer.

Exploration of in vitro cytotoxic and in ovo antiangiogenic activity of ethyl acetate extract of Penicillium oxalicum

Fungal endophytes have established new paradigms in the area of biomedicine due to their ability to produce metabolites of pharmacological importance. The present study reports the in vitro cytotoxic and in ovo antiangiogenic activity of the ethyl acetate (EA) extract of Penicillium oxalicum and their chemical profiling through Gas Chromatography-Mass Spectrometry analysis. Treatment of the EA extract of P. oxalicum to the selected human breast cancer cell lines (MDA-MB-231 and MCF-7) leads to the reduced glucose uptake and increased nitric oxide production suggesting the cytotoxic activity of EA extract of P. oxalicum. Our results further show that treatment of EA extract of P. oxalicum attenuates the colony number, cell migration ability and alters nuclear morphology in both the human breast cancer cell lines. Furthermore, the treatment of EA extract of P. oxalicum mediates apoptosis by increasing the expression of BAX, P21, FADD, and CASPASE-8 genes, with increased Caspase-3 activity. Additionally, in ovo chorioallantoic membrane (CAM) assay showed that the treatment of EA extract of P. oxalicum leads to antiangiogenic activity with perturbed formation of blood vessels. Overall, our findings suggest that the EA extract of P. oxalicum show in vitro cytotoxic and antiproliferative activity against human breast cancer cell lines, and in ovo antiangiogenic activity in CAM model.

A multifunctional integrated biomimetic spore nanoplatform for successively overcoming oral biological barriers

The biological barriers have seriously restricted the efficacious responses of oral delivery system in diseases treatment. Utilizing a carrier based on the single construction means is hard to overcome these obstacles simultaneously because the complex gastrointestinal tract environment requires carrier to have different or even contradictory properties. Interestingly, spore capsid (SC) integrates many unique biological characteristics, such as high resistance, good stability etc. This fact offers a boundless source of inspiration for the construction of multi-functional oral nanoplatform based on SC without further modification. Herein, we develop a type of biomimetic spore nanoplatform (SC@DS NPs) to successively overcome oral biological barriers. Firstly, doxorubicin (DOX) and sorafenib (SOR) are self-assembled to form carrier-free nanoparticles (DS NPs). Subsequently, SC is effectively separated from probiotic spores and served as a functional vehicle for delivering DS NPs. As expect, SC@DS NPs can efficaciously pass through the rugged stomach environment after oral administration and further be transported to the intestine. Surprisingly, we find that SC@DS NPs exhibit a significant improvement in the aspects of mucus penetration and transepithelial transport, which is related to the protein species of SC. This study demonstrates that SC@DS NPs can efficiently overcome multiple biological barriers and improve the therapeutic effect.

Reversibly "double locked" hydroxycamptothecin prodrug nanoparticles for targeted chemotherapy of lung cancer

Prodrug assembled nanoparticles integrate the merits of both prodrug and nanoparticle, which significantly improve pharmacokinetic parameters, enhance tumorous accumulation and decrease adverse effects, while they are challenged by disassembly upon dilution in blood, masking the superiority of nanoparticles (NPs). Herein, a reversibly "double locked" hydroxycamptothecin (HCPT) prodrug nanoparticle decorated with cyclic RGD peptide (cRGD) is developed for safe and efficient chemotherapy of orthotopic lung cancer in mice. HCPT prodrug is constructed from acetal (ace)-linked cRGD-PEG-ace-HCPT-ace-acrylate polymer, which is self-assembled into the nanoparticles with "the first lock" of HCPT. Then the nanoparticles undergo the in situ UV-crosslinking of the acrylate residues for constructing "the second lock" of HCPT. The obtained "double locked" nanoparticles (T-DLHN) with simple and well-defined construction are demonstrated to possess extremely high stability against 100-fold dilution and acid-triggered "unlock" including de-crosslinking and liberation of the pristine HCPT. In an orthotopic lung tumor of mouse model, T-DLHN reveals a prolonged circulation time of about 5.0 h, superb lung tumor-homing capacity with tumorous drug uptake of about 7.15%ID/g, resulting in significantly boosted anti-tumor activity and reduced adverse effects. Hence, these nanoparticles utilizing "double lock" and acid-triggered "unlock" strategies represent a unique and promising nanoplatform for safe and efficient drug delivery. STATEMENT OF SIGNIFICANCE: Prodrug assembled nanoparticles have the unique properties of the well-defined structure, systemic stability, improved pharmacokinetics, passive targeting and decreased adverse effects. However, prodrug assembled NPs would disassemble against extensive dilution in the blood circulation when intravenously injected into the body. Herein, we have designed a cRGD-directed reversibly "double-locked" HCPT prodrug nanoparticle (T-DLHN) for safe and efficient chemotherapy of orthotopic A549 human lung tumor xenografts. Upon intravenous injection, T-DLHN can overcome the shortcoming of disassembly against extensive dilution, prolong the circulation time due to the "double locked" configuration and then mediate targeted drug delivery into the tumors. After uptaken into the cells, T-DLHN undergoes concurrent de-crosslinking and liberation of HCPT under acidic condition for enhanced chemotherapeutic efficacy with negligible adverse effects.

Platelet-mimicking supramolecular nanomedicine with precisely integrated prodrugs for cascade amplification of synergistic chemotherapy

Camptothecin (CPT) and cisplatin (Pt) have shown synergistic effects on a variety of cancers during preclinical and clinical studies. However, the ratio of the two drugs often could not be precisely regulated in different delivery systems, which hinders the desired synergistic effect. In addition, the low delivery efficiency of the two drugs to the tumor further impedes the ideal therapeutic outcomes. Herein, we report that a platelet-mimicking supramolecular nanomedicine (SN) could precisely control of the ratio of CPT and Pt with a high tumor accumulation rate for cascade amplification of synergistic chemotherapy. The SN was fabricated via the host-guest interaction between cucurbit[7]uril conjugated hyaluronic acid (HA-CB[7]) and adamantane (ADA) respectively functionalized CPT- and Pt-based prodrugs. The ratio of CPT and Pt in the SN could be facilely regulated by simply controlling the loading ratio, based on the strong binding affinity between CB[7] and ADA, and SN60 with 60% CPT and 40% Pt showed the highest synergistic effects on 4T1 cells. To improve the tumor accumulation efficiency of SN, 5,6-dimethylxanthenone-4-acetic acid (DMXAA, a tumor vasculature-disruptive agent) was loaded into the optimized SN and then coated with platelet membrane to yield platelet-mimicking supramolecular nanomedicine (D@SN-P). D@SN-P could first passively accumulate in tumors owing to the enhanced permeability and retention (EPR) effect after intravenous administration. The initially release of DMXAA from D@SN-P could induce tumor vascular disruption, and the resultant epithelial collagen exposure around the disrupted tumor vasculature provided a target for further recruitment of platelet-mimicking SN, leading to cascade amplification of tumor accumulation with synergistic chemotherapy. Hence, this platelet-mimicking supramolecular nanomedicine presents a universal supramolecular strategy to finely regulate the ratio of loaded pro-drugs, and improve the accumulation efficiency to amplify chemotherapy via platelet-mimics.

Design and Synthesis of New 4-(3,4,5-Trimethoxyphenyl)Thiazole-Pyrimidine Derivatives as Potential Antiproliferative Agents

A new series of 3,4,5-trimethoxyphenyl thiazole pyrimidines has been synthesized and biologically evaluated for its in vitro anticancer activity. Compounds 4a, 4b, and 4h with substituted piperazine showed the best antiproliferative activity. In the NCI-60 cell line screening, compound 4b showed promising cytostatic activity against multiple cell lines. Notably, it elicited a GI value of 86.28% against the NSCL cancer cell line HOP-92 at a 10 μM dose. Compounds 4a and 4h at 10 μM showed promising GI values of 40.87% and 46.14% against HCT-116 colorectal carcinoma and SK-BR-3 breast cancer cell lines, respectively. ADME-Tox prediction of compounds 4a, 4b, and 4h revealed their acceptable drug-likeness properties. In addition, compounds 4a, 4b, and 4h showed a high probability of targeting kinase receptors via Molinspiration and Swiss TargetPrediction.

Cancer Cell-Specific Fluorescent Prodrug Delivery Platforms

Targeting cancer cells with high specificity is one of the most essential yet challenging goals of tumor therapy. Because different surface receptors, transporters, and integrins are overexpressed specifically on tumor cells, using these tumor cell-specific properties to improve drug targeting efficacy holds particular promise. Targeted fluorescent prodrugs not only improve intracellular accumulation and bioavailability but also report their own localization and activation through real-time changes in fluorescence. In this review, efforts are highlighted to develop innovative targeted fluorescent prodrugs that efficiently accumulate in tumor cells in different organs, including lung cancer, liver cancer, cervical cancer, breast cancer, glioma, and colorectal cancer. The latest progress and advances in chemical design and synthetic considerations in fluorescence prodrug conjugates and how their therapeutic efficacy and fluorescence can be activated by tumor-specific stimuli are reviewed. Additionally, novel perspectives are provided on strategies behind engineered nanoparticle platforms self-assembled from targeted fluorescence prodrugs, and how fluorescence readouts can be used to monitor the position and action of the nanoparticle-mediated delivery of therapeutic agents in preclinical models. Finally, future opportunities for fluorescent prodrug-based strategies and solutions to the challenges of accelerating clinical translation for the treatment of organ-specific tumors are proposed.

Polysaccharide-Based Stimulus-Responsive Nanomedicines for Combination Cancer Immunotherapy

Cancer immunotherapy is a promising antitumor approach, whereas nontherapeutic side effects, tumor microenvironment (TME) intricacy, and low tumor immunogenicity limit its therapeutic efficacy. In recent years, combination immunotherapy with other therapies has been proven to considerably increase antitumor efficacy. However, achieving codelivery of the drugs to the tumor site remains a major challenge. Stimulus-responsive nanodelivery systems show controlled drug delivery and precise drug release. Polysaccharides, a family of potential biomaterials, are widely used in the development of stimulus-responsive nanomedicines due to their unique physicochemical properties, biocompatibility, and modifiability. Here, the antitumor activity of polysaccharides and several combined immunotherapy strategies (e.g., immunotherapy combined with chemotherapy, photodynamic therapy, or photothermal therapy) are summarized. More importantly, the recent progress of polysaccharide-based stimulus-responsive nanomedicines for combination cancer immunotherapy is discussed, with the focus on construction of nanomedicine, targeted delivery, drug release, and enhanced antitumor effects. Finally, the limitations and application prospects of this new field are discussed.

Natural killer cells strengthen antitumor activity of cisplatin by immunomodulation and ameliorate cisplatin-induced side effects

PURPOSE

Cisplatin-based chemotherapy is now an important treatment for improving bladder cancer prognosis. However, challenges in clinical treatment remain due to the numerous side effects of chemotherapy. Natural killer (NK) cells regulate certain immune responses and play a significant role in tumor surveillance and control. The efficacy of NK cells combined with cisplatin for chemoimmunotherapy in bladder cancer remains poorly understood.

METHODS

In this study, we established an MB49 tumor-bearing mouse model, tumor growth was measured in a control group and in groups treated with cisplatin, NK cells or both. Organ indices, biochemical indicators of blood serum, and expression of apoptotic proteins were used to assess the extent of organ damage. ELISA and immunohistochemistry were used to analyze the levels of immune cells and cytokine expression in serum, spleen, and tumor tissue.

RESULTS

NK cells combined with cisplatin exhibited better antitumor activity. NK cells also alleviated the organ damage caused by cisplatin and improved the survival rate. Treatment with NK cells increased the expression of IL-2 and IFN-γ as well as the number of CD4 + T cells. Additionally, cisplatin increased the expression of natural killer group 2, member D (NKG2D) ligands thus activating NK cells to kill tumor cells.

CONCLUSION

NK cells could alleviate the side effects of cisplatin treatment and enhance antitumor activity. The combination of NK cells and cisplatin thus provides a promising option for chemoimmunotherapy for bladder cancer.

pH-responsive bufadienolides nanocrystals decorated by chitosan quaternary ammonium salt for treating colon cancer

Due to its poor prognosis and propensity for metastasizing, colon cancer, a frequent cancer of the gastrointestinal system, has a high morbidity and mortality rate. However, the harsh physiological conditions of the gastrointestinal tract can cause the anti-cancer medicine bufadienolides (BU) to lose some of its structure, impairing its ability to fight cancer. In this study, pH-responsive bufadienolides nanocrystals decorated by chitosan quaternary ammonium salt (HE BU NCs) were successfully constructed by a solvent evaporation method to improve the bioavailability, release characteristics and intestinal transport ability of BU. In vitro, studies have shown that HE BU NCs could improve BU internalization, significantly induce apoptosis, decrease mitochondrial membrane potential, and increase ROS levels in tumour cells. In vivo, experiments showed that HE BU NCs effectively targeted intestinal sites, increased their retention time, and exerted antitumor activity through Caspase-3 and Bax/Bcl-2 ratio pathways. In conclusion, pH-responsive bufadienolides nanocrystals decorated by chitosan quaternary ammonium salt could protect bufadienolides from the destruction of an acidic environment, achieve synergistic release in the intestinal site, improve oral bioavailability, and ultimately exert anti-colon cancer effects, which is a promising strategy for the treatment of colon cancer.

Stimuli-responsive heparin-drug conjugates co-assembled into stable nanomedicines for cancer therapy

The combination of chemotherapy and photodynamic therapy (PDT) has the potential to complement single-drug therapies, but chemotherapeutic agents and photosensitizers often have compromised therapeutic efficacies and strong toxic effects. In this study, we exploited nanotechnology to address this challenge by utilizing heparin as a carrier for co-delivery of chemotherapeutic drugs and photosensitizers for synergistic cancer therapy. Specifically, heparin-paclitaxel (HP-PTX) and heparin-pyropheophorbide-a (HP-Ppa) were synthesized by attaching paclitaxel (PTX), a small molecular chemotherapeutic drug, through a reactive oxygen species (ROS)-responsive linker and Ppa, a photosensitizer, to heparin, respectively. Two conjugates co-assembled into a nanomedicine, HP-PP nanoparticles (NPs), for controllable co-delivery of Ppa and PTX into tumor cells. HP-PP NPs significantly enhanced the in vitro stability of HP-Ppa and the photostability of Ppa, and the synergistic actions of chemotherapy and PDT were confirmed from both in vitro and in vivo antitumor studies. Notably, HP-PP NPs enhanced tumor accumulation of Ppa up to 11-fold and the treatment of 4T1 tumor-bearing mice with HP-PP NPs resulted in a tumor growth inhibition of 98.1% without systemic toxicity. The strategy of co-assembly of heparin conjugates may offer great potential in enhancing the efficacy of combination therapy. STATEMENT OF SIGNIFICANCE: : We proposed a nano-delivery system, HP-PP NPs, which was constructed by co-assembly of heparin-paclitaxel (HP-PTX) and heparin-pyropheophorbide-a (HP-Ppa), to co-deliver PTX and Ppa for synergistic cancer therapy. HP-PP NPs enhanced the photostability and the in vitro stability of Ppa and HP-Ppa, and induced greater cytotoxicity than HP-PTX NPs or HP-Ppa NPs. This co-delivery system displays enhanced tumor accumulation and has a remarkable synergistic antitumor effect with a tumor growth inhibition of 98.1%.

Mechanisms of Radical Formation on Chemically Modified Graphene Oxide under Near Infrared Irradiation

In this work, the mechanisms of radical generation on different functionalized graphene oxide (GO) conjugates under near-infrared (NIR) light irradiation are investigated. The GO conjugates are designed to understand how chemical functionalization can influence the generation of radicals. Both pristine and functionalized GO are irradiated by a NIR laser, and the production of different reactive oxygen species (ROS) is investigated using fluorimetry and electron paramagnetic resonance to describe the type of radicals present on the surface of GO. The mechanism of ROS formation involves a charge transfer from the material to the oxygen present in the media, via the production of superoxide and singlet oxygen. Cytotoxicity and effects of ROS generation are then evaluated using breast cancer cells, evidencing a concentration dependent cell death associated to the heat and ROS. The study provides new hints to understand the photogeneration of radicals on the surface of GO upon near infrared irradiation, as well as, to assess the impact on these radicals in the context of a combined drug delivery system and phototherapeutic approach. These discoveries open the way for a better control of phototherapy-based treatments employing graphene-based materials.

MCL-1 Inhibitor S63845 Distinctively Affects Intramedullary and Extramedullary Hematopoiesis

Conventional chemotherapy for killing cancer cells using cytotoxic drugs suffers from low selectivity, significant toxicity, and a narrow therapeutic index. Hyper-specific targeted drugs achieve precise destruction of tumors by inhibiting molecular pathways that are critical to tumor growth. Myeloid cell leukemia 1 (MCL-1), an important pro-survival protein in the BCL-2 family, is a promising antitumor target. In this study, we chose to investigate the effects of S63845, a small-molecule inhibitor that targets MCL-1, on the normal hematopoietic system. A mouse model of hematopoietic injury was constructed, and the effects of the inhibitor on the hematopoietic system of mice were evaluated via routine blood tests and flow cytometry. The results showed that S63845 affected the hematopoiesis of various lineages in the early stage of action, causing extramedullary compensatory hematopoiesis in the myeloid and megakaryocytic lineages. The maturation of the erythroid lineage in the intramedullary and extramedullary segments was blocked to varying degrees, and both the intramedullary and extramedullary lymphoid lineages were inhibited. This study provides a complete description of the effects of MCL-1 inhibitor on the intramedullary and extramedullary hematopoietic lineages, which is important for the selection of combinations of antitumor drugs and the prevention of adverse hematopoiesis-related effects.

Antibody-drug conjugates and bispecific antibodies targeting cancers: applications of click chemistry

Engineering approaches using antibody drug conjugates (ADCs) and bispecific antibodies (bsAbs) are designed to overcome the limitations of conventional chemotherapies and therapeutic antibodies such as drug resistance and non-specific toxicity. Cancer immunotherapies have been shown to be clinically successful with checkpoint blockade and chimeric antigen receptor T cell therapy; however, overactive immune systems still represent a major problem. Given the complexity of a tumor environment, it would be advantageous to have a strategy targeting two or more molecules. We highlight the necessity and importance of a multi-target platform strategy against cancer. Approximately 400 ADCs and over 200 bsAbs are currently being clinically developed for several indications, with promising signs of therapeutic activity. ADCs include antibodies that recognize tumor antigens, linkers that stably connect drugs, and powerful cytotoxic drugs, also known as payloads. ADCs have direct therapeutic effects by targeting cancers with a strong payload. Another type of drug that uses antibodies are bsAbs, targeting two antigens by linking to antigen recognition sites or bridging cytotoxic immune cells to tumor cells, resulting in cancer immunotherapy. Three bsAbs and one ADC have been approved for use by the FDA and the EMA in 2022. Among these, two of the bsAbs and the one ADC are used for cancers. We introduced that bsADC, a combination of ADC and bsAbs, has yet to be approved and several candidates are in the early stages of clinical development in this review. bsADCs technology helps increase the specificity of ADCs or the internalization and killing ability of bsAbs. We also briefly discuss the application of click chemistry in the efficient development of ADCs and bsAbs as a conjugation strategy. The present review summarizes the ADCs, bsAbs, and bsADCs that have been approved for anti-cancer or currently in development. These strategies selectively deliver drugs to malignant tumor cells and can be used as therapeutic approaches for various types of cancer.

Recent Progress in Carrier-Free Nanomedicine for Tumor Phototherapy

Safe and effective strategies are urgently needed to fight against the life-threatening diseases of various cancers. However, traditional therapeutic modalities, such as radiotherapy, chemotherapy and surgery, exhibit suboptimal efficacy for malignant tumors owing to the serious side effects, drug resistance and even relapse. Phototherapies, including photodynamic therapy (PDT) and photothermal therapy (PTT), are emerging therapeutic strategies for localized tumor inhibition, which can produce a large amount of reactive oxygen species (ROS) or elevate the temperature to initiate cell death by non-invasive irradiation. In consideration of the poor bioavailability of phototherapy agents (PTAs), lots of drug delivery systems have been developed to enhance the tumor targeted delivery. Nevertheless, the carriers of drug delivery systems inevitably bring biosafety concerns on account of their metabolism, degradation, and accumulation. Of note, carrier-free nanomedicine attracts great attention for clinical translation with synergistic antitumor effect, which is characterized by high drug loading, simplified synthetic method and good biocompatibility. In this review, the latest advances of phototherapy with various carrier-free nanomedicines are summarized, which may provide a new paradigm for the future development of nanomedicine and tumor precision therapy.

Lactone Stabilized by Crosslinked Cyclodextrin Metal-Organic Frameworks to Improve Local Bioavailability of Topotecan in Lung Cancer

The protection of unstable anticancer molecules and their delivery to lesions are challenging issues in cancer treatment. Topotecan (TPT), a classic cytotoxic drug, is widely used for treating refractory lung cancer. However, the therapeutic effects of TPT are jeopardized by its active lactone form that is intrinsically hydrolyzed in physiological fluids, resulting in low bioavailability. Herein, the TPT-loaded crosslinked cyclodextrin metal-organic framework (TPT@CL-MOF) was engineered to improve the local bioavailability of TPT for the treatment of lung cancer. CL-MOF exhibited the efficient loading (12.3 wt%) of TPT with sustained release characteristics. In particular the formulation offered excellent protection in vitro against hydrolysis and increased the half-life of TPT from approximately 0.93 h to 22.05 h, which can be attributed to the host-guest interaction between cyclodextrin and TPT, as confirmed by molecular docking. The TPT@CL-MOF could effectively kill the cancer cells and inhibit the migration and invasion of B16F10 cells in vitro. Moreover, TPT@CL-MOF was efficiently distributed in the lungs after intravenous administration. In an in vivo study using a B16F10 pulmonary metastatic tumor model, TPT@CL-MOF significantly reduced the number and size of metastatic lung nodules at a reduced low dose by five times, and no noticeable side effects were observed. Therefore, this study provides a possible alternative therapy for the treatment of lung cancer with the camptothecin family drugs or other unstable therapeutically significant molecules.

Multicomponent carrier-free nanodrugs for cancer treatment

Nanocarriers can be used to deliver insoluble anticancer drugs to optimize therapeutic efficacy. However, the potential toxicity of nanocarriers cannot be ignored. Carrier-free nanodrugs are emerging safe drug delivery systems, which are composed of multiple components, such as drugs, bioactive molecules and functional ingredients, avoiding the usage of inert carrier materials and offering advantages that include high drug loading, low toxicity, synergistic therapy, versatile design, and easy surface functionalization. Therefore, how to design multicomponent carrier-free nanodrugs is becoming a priority. In this review, the common strategies for rapid construction of multicomponent carrier-free nanodrugs are briefly explored from the perspective of methodology. The properties of organic-organic, organic-inorganic and inorganic-inorganic multiple carrier-free nanosystems are analyzed according to wettability and in-depth understanding is provided. Further advances in the applications of multiple carrier-free nanodrugs are outlined in anticipation of grasping the intrinsic nature for the design and development of carrier-free nanodrugs.

Nanoparticles-based phototherapy systems for cancer treatment: Current status and clinical potential

Remarkable progress in phototherapy has been made in recent decades, due to its non-invasiveness and instant therapeutic efficacy. In addition, with the rapid development of nanoscience and nanotechnology, phototherapy systems based on nanoparticles or nanocomposites also evolved as an emerging hotspot in nanomedicine research, especially in cancer. In this review, first we briefly introduce the history of phototherapy, and the mechanisms of phototherapy in cancer treatment. Then, we summarize the representative development over the past three to five years in nanoparticle-based phototherapy and highlight the design of the innovative nanoparticles thereof. Finally, we discuss the feasibility and the potential of the nanoparticle-based phototherapy systems in clinical anticancer therapeutic applications, aiming to predict future research directions in this field. Our review is a tutorial work, aiming at providing useful insights to researchers in the field of nanotechnology, nanoscience and cancer.

Tumor extracellular matrix modulating strategies for enhanced antitumor therapy of nanomedicines

Nanomedicines have shown a promising strategy for cancer therapy because of their higher safety and efficiency relative to small-molecule drugs, while the dense extracellular matrix (ECM) in tumors often acts as a physical barrier to hamper the accumulation and diffusion of nanoparticles, thus compromising the anticancer efficacy. To address this issue, two major strategies including degrading ECM components and inhibiting ECM formation have been adopted to enhance the therapeutic efficacies of nanomedicines. In this review, we summarize the recent progresses of tumor ECM modulating strategies for enhanced antitumor therapy of nanomedicines. Through degrading ECM components or inhibiting ECM formation, the accumulation and diffusion of nanoparticles in tumors can be facilitated, leading to enhanced efficacies of chemotherapy and phototherapy. Moreover, the ECM degradation can improve the infiltration of immune cells into tumor tissues, thus achieving strong immune response to reject tumors. The adoptions of these two ECM modulating strategies to improve the efficacies of chemotherapy, phototherapy, and immunotherapy are discussed in detail. A conclusion, current challenges and outlook are then given.

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Extracellular matrix modulating strategies have been adopted to enhance the therapeutic efficacies of nanomedicines.

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Degrading extracellular matrix components or inhibiting extracellular matrix formation can improve the accumulation and diffusion of nanoparticles in tumors and the infiltration of immune cells into tumor tissues.

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The adoptions of two extracellular matrix modulating strategies to improve the efficacies of chemotherapy, phototherapy, and immunotherapy are summarized.

Nanocarriers containing platinum compounds for combination chemotherapy

Platinum compounds-based drugs are used widely in the clinic for the treatment of many types of cancer. However, serious undesirable side effects and intrinsic or acquired resistance limit their successful clinic use. Nanocarrier-based combination chemotherapy is considered to be an effective strategy to resolve these challenges. This review introduces the recent advance in nanocarriers containing platinum compounds for combination cancer chemotherapy, including liposomes, polymer nanoparticles, polymer micelles, mesoporous silica nanoparticles, carbon nanohors, polymer-caged nanobins, carbon nanotube, nanostructured lipid carriers, solid lipid nanoparticles, and multilayered fiber mats in detail.

Tumor Microenvironment-Based Stimuli-Responsive Nanoparticles for Controlled Release of Drugs in Cancer Therapy

With the development of nanomedicine technology, stimuli-responsive nanocarriers play an increasingly important role in antitumor therapy. Compared with the normal physiological environment, the tumor microenvironment (TME) possesses several unique properties, including acidity, high glutathione (GSH) concentration, hypoxia, over-expressed enzymes and excessive reactive oxygen species (ROS), which are closely related to the occurrence and development of tumors. However, on the other hand, these properties could also be harnessed for smart drug delivery systems to release drugs specifically in tumor tissues. Stimuli-responsive nanoparticles (srNPs) can maintain stability at physiological conditions, while they could be triggered rapidly to release drugs by specific stimuli to prolong blood circulation and enhance cancer cellular uptake, thus achieving excellent therapeutic performance and improved biosafety. This review focuses on the design of srNPs based on several stimuli in the TME for the delivery of antitumor drugs. In addition, the challenges and prospects for the development of srNPs are discussed, which can possibly inspire researchers to develop srNPs for clinical applications in the future.

Rational Design, Synthesis, and Biological Evaluation of Novel S1PR2 Antagonists for Reversing 5-FU-Resistance in Colorectal Cancer

Resistance to 5-FU reduces its clinical efficacy for the treatment of colorectal cancer. Sphingosine-1-phosphate receptor 2 (S1PR2) has emerged as a potential target to reverse 5-FU-resistance by inhibiting the expression of dihydropyrimidine dehydrogenase (DPD). In this study, 38 novel S1PR2 antagonists based on aryl urea structure were designed and synthesized, and the structure-activity relationship was investigated based on the S1PR2 binding assay. Representative compound 43 potently interacts with S1PR2 with a K_D value of 0.73 nM. It displays potent 5-FU resensitizing activity in multiple 5-FU-resistant tumor cell lines, particularly in SW620/5-FU (EC₅₀ = 1.99 ± 0.03 μM) but shows no cytotoxicity in the normal colon cell line NCM460 up to 1000 μM. Moreover, 43 significantly enhances the antitumor efficacy of 5-FU in the SW620/5-FU animal model. These data suggest that 43 could be a novel lead compound for developing a 5-FU resensitizing agent.

Therapeutic Response of Multifunctional Lipid and Micelle Formulation in Hepatocellular Carcinoma

Hepatic stellate cells (HSCs), as an important part of the tumor microenvironment (TME), could be activated by tumor cells as cancer-associated fibroblasts (CAFs), thereby promoting the production of extracellular matrix (ECM) and favoring the development of tumors. Therefore, blocking the "CAFs-ECM" axis is a promising pathway to improve antitumor efficacy. Based on this, we developed a multifunctional nanosized delivery system composed of hyaluronic acid-modified pH-sensitive liposomes (CTHLs) and glycyrrheic acid-modified nanomicelles (DGNs), which combines the advantages of targeted delivery, pH-sensitivity, and deep drug penetration. To mimic actual TME, a novel HSCs+BEL-7402 cocultured cell model and a m-HSCs+H22 coimplanted mice model were established. As expected, CTHLs and DGNs could target CAFs and tumor cells, respectively, and promote the drug penetration and retention in tumor regions. Notably, CTHLs+DGNs not only exhibited a superior antitumor effect in three-level tumor-bearing mice but also presented excellent antimetastasis efficiency in lung-metastatic mice. The antitumor mechanism revealed that the lipid&micelle mixed formulations effectively inhibited the activation of CAFs, reduced the deposition of ECM, and reversed the epithelial-mesenchymal transition (EMT) of tumor cells. In brief, the nanosized delivery system composed of CTHLs and DGNs could effectively improve the therapeutic effect of liver cancer by blocking the "CAFs-ECM" axis, which has a good clinical application prospect.

Inorganic nanoparticle-based advanced cancer therapies: promising combination strategies

Inorganic nanoparticles for drug delivery in cancer treatment offer many potential advantages because they can maximize therapeutic effect through targeting ligands while minimizing off-target side-effects through drug adsorption and infiltration. Although inorganic nanoparticles were introduced as drug carriers, they have emerged as having the capacity for combined therapeutic capabilities, including anticancer effects through cytotoxicity, suppression of oncogenes and cancer cell signaling pathway inhibition. The most promising advanced strategies for cancer therapy are as synergistic platforms for RNA interference (siRNA, miRNA, shRNA) and as synergistic drug delivery agents for the inhibition of cancer cell signaling pathways. The present work summarizes relevant current work, the promise of which is suggested by a projected compound annual growth rate of ∼20% for drug delivery alone.

Multiple Strikes Achieve Remarkable Tumor-Inhibition Efficiency via Multi-mechanism Combination

Breast cancer treatment has been challenging all the time because cancer cells have multiple signaling pathways; so, breast cancer still remains a threat to the lives and health of many patients. While common single drug therapies inhibit only one pathway, the combination of multiple mechanisms offers the potential to simultaneously suppress multiple targets and pathways to kill cancer cells more effectively. It is reported that autophagy caused by autophagy inducers and apoptosis caused by some chemotherapeutic drugs can promote ferroptosis to some extent; herein, we combined these three pathways and constructed a multifunctional dual-responsive release nanosystem of Rap@mFe₃O₄-DOX-HA that achieved the ferroptosis-autophagy-apoptosis synergistic effect for cancer treatment. Mesoporous Fe₃O₄ (mFe₃O₄) was set as the carrier and can also release Fe ions for ferroptosis, the autophagy inducer rapamycin (Rap) was wrapped in the carrier to trigger autophagy, and the chemotherapeutic drug doxorubicin (DOX) was used as the apoptosis inducer. At the tumor site, the prepared Rap@mFe₃O₄-DOX-HA nanoparticles split and released DOX/Rap in response to H⁺/GSH. From in vivo and in vitro studies, it was found that Rap@mFe₃O₄-DOX-HA nanoparticles effectively inhibited the migration of 4T1 cells, furthermore, they struck cancer cells through multiple pathways and greatly improved the anti-tumor effect. Therefore, the strategy of multi-mechanism combination achieved a therapeutic effect of 1 + 1 > 2.