Polyethylenimine modified with 2,3-dimethylmaleic anhydride potentiates the antitumor efficacy of conventional chemotherapy

Cholesterol Targeted Catalytic Hydrogel Fueled by Tumor Debris can Enhance Microwave Ablation Therapy and Anti-Tumor Immune Response

The immunosuppressive residual tumor microenvironment (IRTM) is a key factor in the high recurrence and metastasis rates of hepatocellular carcinoma (HCC) after microwave ablation (MWA). Cholesterol-rich tumor fragments significantly contribute to IRTM deterioration. This study developed a cholesterol-targeted catalytic hydrogel, DA-COD-OD-HCS, to enhance the synergy between MWA and immune checkpoint inhibitors (ICIs) for HCC treatment. Cholesterol oxidase (COD), modified with dimethyl maleic anhydride (DA) for release in acidic IRTM, is used to degrade cholesterol. Oxydextran (OD) and hemin-chitosan (HCS) formed a dual network gel, ensuring long-term fixation of COD and hemin in the IRTM post-MWA. In both in vitro and in vivo HCC models, DA-COD-OD-HCS effectively released COD, degraded cholesterol, and induced tumor cell ferroptosis, enhancing the antitumor immune response. Combined with anti-PD-L1 immunotherapy, this strategy inhibited primary tumor growth and distant metastases, without side effects on adjacent tissues. This work highlights that cholesterol-targeting catalytic hydrogels fueled by tumor debris can significantly improve the efficacy of MWA and ICIs, offering a novel therapeutic approach for HCC.

Research progress in tumor therapy of carrier-free nanodrug

Carrier-free nanodrugs are a novel type of drug constructed by the self-assembly of drug molecules without carrier involvement. They have the characteristics of small particle size, easy penetration of various barriers, targeting tumors, and efficient release. In recent years, carrier-free nanodrugs have become a hot topic in tumor therapy as they solve the problems of low drug loading, poor biocompatibility, and low uptake efficiency of carrier nanodrugs. A series of recent studies have shown that carrier-free nanodrugs play a vital role in the treatment of various tumors, with similar or better effects than carrier nanodrugs. Based on the literature published in the past decades, this paper first summarizes the recent progress in the assembly modes of carrier-free nanodrugs, then describes common therapeutic modalities of carrier-free nanodrugs in tumor therapy, and finally depicts the existing challenges along with future trends of carrier-free nanodrugs. We hope that this review can guide the design and application of carrier-free nanodrugs in the future.

Metabolomics combined with network pharmacology reveals the potential development value of Campanumoea javanica Bl. and its metabolite differences with Codonopsis Radix

Campanumoea javanica Bl. (CJ) traditionally used in Southwestern China, is now widely consumed as a health food across the nation. Due to its similar efficacy to Codonopsis Radix (CR) and their shared botanical family, CJ is often used as a substitute for CR. According to the Chinese Pharmacopoeia, Codonopsis pilosula var. modesta (Nannf.) L.T. Shen (CPM), Codonopsis pilosula (Franch.) Nannf. (CP), and Codonopsis tangshen Oliv. (CT) are the primary sources of CR. However, details on the differences in composition, effectiveness, and compositional between CJ and CR are still limited. Besides, there is little evidence to support the application of CJ as a drug. In this study, we employed widely targeted metabolomics, network pharmacology analysis, and molecular docking to explore the disparities in metabolite profiles between CJ and CR and to predict the pharmacological mechanisms of the dominant differential metabolites of CJ and their potential medicinal applications. The widely targeted metabolomics results indicated that 1,076, 1,102, 1,102, and 1,093 compounds, most phenolic acids, lipids, amino acids, and flavonoids, were characterized in CJ, CPM, CP, and CT, respectively. There were an average of 1061 shared compounds in CJ and CRs, with 95.07% similarity in metabolic profiles. Most of the metabolites in CJ were previously unreported. Twelve of the seventeen dominant metabolites found in CJ were directly associated with treating cancer and lactation, similar to the traditional medicinal efficacy. The molecular docking results showed that the dominant metabolites of CJ had good docking activity with the core targets PIK3R1, PIK3CA, ESR1, HSP90AA1, EGFR, and AKT1. This study provides a scientific basis for understanding the similarities and differences between CJ and CR at the metabolome level, offering a theoretical foundation for developing innovative medications from CJ. Additionally, it significantly enhances the metabolite databases for both CJ and CR.

Nano-Engineering Strategies for Tumor-Specific Therapy

Nanodelivery systems (NDSs) provide promising prospects for decreasing drug doses, reducing side effects, and improving therapeutic effects. However, the bioapplications of NDSs are still compromised by their fast clearance, indiscriminate biodistribution, and limited tumor accumulation. Hence, engineering modification of NDSs aiming at promoting tumor-specific therapy and avoiding systemic toxicity is usually needed. An NDS integrating various functionalities, including flexible camouflage, specific biorecognition, and sensitive stimuli-responsiveness, into one sequence would be "smart" and highly effective. Herein, we systematically summarize the related principles, methods, and progress. At the end of the review, we predict the obstacles to precise nanoengineering and prospects for the future application of NDSs.

pH-Responsive Polymer Nanomaterials for Tumor Therapy

The complexity of the tumor microenvironment presents significant challenges to cancer therapy, while providing opportunities for targeted drug delivery. Using characteristic signals of the tumor microenvironment, various stimuli-responsive drug delivery systems can be constructed for targeted drug delivery to tumor sites. Among these, the pH is frequently utilized, owing to the pH of the tumor microenvironment being lower than that of blood and healthy tissues. pH-responsive polymer carriers can improve the efficiency of drug delivery in vivo, allow targeted drug delivery, and reduce adverse drug reactions, enabling multifunctional and personalized treatment. pH-responsive polymers have gained increasing interest due to their advantageous properties and potential for applicability in tumor therapy. In this review, recent advances in, and common applications of, pH-responsive polymer nanomaterials for drug delivery in cancer therapy are summarized, with a focus on the different types of pH-responsive polymers. Moreover, the challenges and future applications in this field are prospected.

Peptide dendrimers as potentiators of conventional chemotherapy in the treatment of pancreatic cancer in a mouse model

Chemotherapy is the recommended treatment for patients with advanced pancreatic ductal adenocarcinoma (PDAC). However, efficacy of traditional chemotherapy is not satisfactory due to the presence of a dense dysplastic tumor stroma which prevents drug accumulation in and deep penetration into tumors. To overcome these obstacles, we designed and synthesized peptide dendrimers as potentiators of conventional chemotherapy. The dendrimers markedly promoted free doxorubicin accumulation and penetration deeply into 3D multicellular PDAC tumor cultures upon co-incubation. Co-administration of the dendrimer and doxorubicin into PDAC tumor xenograft-bearing mice greatly increased the doxorubicin concentration in the tumor. In addition, the dendrimer also promoted free doxorubicin internalization into PDAC cells upon co-incubation in media mimicking tumor microenvironment. Finally, a significant enhancement in the anticancer efficacy of doxorubicin and gemcitabine when either of the drugs was individually co-administered with the dendrimer into PDAC tumor xenograft-bearing mice was observed. This was especially pronounced for the combination treatment with the dendrimer and gemcitabine, resulting in a tumor weight decrease to 12.9% compared to the treatment with gemcitabine alone. This can be attributed to the combination of the multi-functionalities of the dendrimer, i.e., promoting free drug accumulation and penetration deeply into tumors and internalization into cancer cells.

The effect of spacers in dual drug-polymer conjugates toward combination therapeutic efficacy

Recently, a great effort has been made to perfect the therapeutic effect of solid tumor, from single-agent therapy to combined therapy and many other polymer-drug conjugations with dual or more anticancer agents due to their promising synergistic effect and higher drug level accumulation towards tumor tissues. Different polymer-drug spacers present diverse therapeutic efficacy, therefore, finding an appropriate spacer is desirable. In this study, dual drugs that are doxorubicin (DOX) and mitomycin C (MMC) were conjugated onto a polymer carrier (xyloglucan) via various peptide or amide bonds, and a series of polymers drug conjugates were synthesized with different spacers and their effect on tumor treatment efficacy was studied both in vitro and in vivo. The result shows that the synergistic effect is better when using different linker to conjugate different drugs rather than using the same spacer to conjugate different drugs on the carrier. Particularly, the finding of this works suggested that, using peptide bond for MMC and amide bond for DOX to conjugate dual drugs onto single XG carrier could improve therapeutic effect and synergy effect. Therefore, in polymer-pharmaceutical formulations, the use of different spacers to optimize the design of existing drugs to enhance therapeutic effects is a promising strategy.

Co-administration of a branched arginine-rich polymer enhances the anti-cancer efficacy of doxorubicin

The severe side-effects and drug resistance development of conventional chemotherapy are mainly caused by poor tumor penetration as well as nonspecific biodistribution and insufficient cellular uptake of drugs. Herein a branched arginine-rich polymer was synthesized and co-administration of this polymer with doxorubicin, a model drug of chemotherapeutic agents, overcame simultaneously the three obstacles shown above. Co-incubation of the polymer promoted doxorubicin penetration deeply into multicellular tumor spheroids and internalization into cancer cells. Upon co-injection of the polymer with doxorubicin into tumor-bearing mice, the enhanced drug accumulation in and deep penetration into tumor tissue were observed compared to injection of doxorubicin alone. A combined therapy of doxorubicin and the polymer in the treatment of tumor-bearing mice showed a marked enhancement in anticancer efficacy compared to doxorubicin alone. Notably, the treatment with the combination regime reduced the doxorubicin dose to one fifth without reducing the antitumor efficacy compared to the treatment with doxorubicin alone. The possible mechanism of action of the polymer was postulated, in which the guanidinium groups of arginine residues in the polymer may play a pivotal role in the action.

Cyclic Anhydrides as Powerful Tools for Bioconjugation and Smart Delivery

Cyclic anhydrides are potent tools for bioconjugation; therefore, they are broadly used in the functionalization of biomolecules and carriers. The pH-dependent stability and reactivity, as well as the physical properties, can be tuned by the structure of the cyclic anhydride used; thus, their application in smart delivery systems has become very important. This review intends to cover the last updates in the use of cyclic anhydrides as pH-sensitive linkers, their differences in reactivity, and the latest applications found in bioconjugation chemistry or chemical biology, and when possible, in drug delivery.

A review on the synthesis of graft copolymers of chitosan and their potential applications

Chitosan is an antimicrobial, biodegradable and biocompatible natural polymer, commercially derived from the partial deacetylation of chitin. Currently modified chitosan has occupied a major part of scientific research. Modified chitosan has excellent biotic characteristics like biodegradation, antibacterial, immunological, metal-binding and metal adsorption capacity and wound-healing ability. Chitosan is an excellent candidate for drug delivery, food packaging and wastewater treatment and is also used as a supporting object for cell culture, gene delivery and tissue engineering. Modification of pure chitosan via grafting improves the native properties of chitosan. Chitosan grafted copolymers exhibit high significance and are extensively used in numerous fields. In this review, modifications of chitosan through several graft copolymerization techniques such as free radical, radiation, and enzymatic were reported and the properties of grafted chitosan were discussed. This review also discussed the applications of grafted chitosan in the fields of drug delivery, food packaging, antimicrobial, and metal adsorption as well as dye removal.