ABSTRACT
The unique characteristics of the tumor microenvironment (TME) could be exploited to develop antitumor nanomedicine strategies. However, in many cases, the actual therapeutic effect is far from reaching our expectations due to the notable tumor heterogeneity. Given the amplified characteristics of TME regulated by vascular disrupting agents (VDAs), nanomedicines may achieve unexpected improved efficacy. Herein, we fabricate platelet membrane-fusogenic liposomes (PML/DP&PPa), namely "platesomes", which actively load the hypoxia-activated pro-prodrug DMG-PR104A (DP) and physically encapsulate the photosensitizer pyropheophorbide a (PPa). Considering the different stages of tumor vascular collapse and shutdown induced by a VDA combretastatin-A4 phosphate (CA4P), PML/DP&PPa is injected 3 h after intraperitoneal administration of CA4P. First, CA4P-mediated tumor hemorrhage amplifies the enhanced permeation and retention (EPR) effect, and the platesome-biological targeting further promotes the tumor accumulation of PML/DP&PPa. Besides, CA4P-induced vascular occlusion inhibits oxygen supply, followed by photodynamic therapy-caused acute tumor hypoxia. This prolonged extreme hypoxia contributes to the complete activation of DP and then high inhibitory effect on tumor growth and metastasis. Thus, such a combining strategy of artificially-regulated TME and bio-inspired platesomes pronouncedly improves tumor drug delivery and boosts tumor hypoxia-selective activation, and provides a preferable solution to high-efficiency cancer therapy.
ABSTRACT
Breast cancer has become the most commonly diagnosed cancer type in the world. A combination of chemotherapy and photothermal therapy (PTT) has emerged as a promising strategy for breast cancer therapy. However, the intricacy of precise delivery and the ability to initiate drug release in specific tumor sites remains a challenging puzzle. Therefore, to ensure that the therapeutic agents are synchronously delivered to the tumor site for their synergistic effect, a multifunctional nanoparticle system (PCRHNs) is developed, which is grafted onto the prussian blue nanoparticles (PB NPs) by reduction-responsive camptothecin (CPT) prodrug copolymer, and then modified with tumor-targeting peptide cyclo(Asp-d-Phe-Lys-Arg-Gly) (cRGD) and hyaluronic acid (HA). PCRHNs exhibited nano-sized structure with good monodispersity, high load efficiency of CPT, triggered CPT release in response to reduction environment, and excellent photothermal conversion under laser irradiation. Furthermore, PCRHNs can act as a photoacoustic imaging contrast agent-guided PTT. In vivo studies indicate that PCRHNs exhibited excellent biocompatibility, prolonged blood circulation, enhanced tumor accumulation, allow tumor-specific chemo-photothermal therapy to achieve synergistic antitumor effects with reduced systemic toxicity. Moreover, hyperthermia-induced upregulation of heat shock protein 70 in the tumor cells could be inhibited by CPT. Collectively, PCRHNs may be a promising therapeutic way for breast cancer therapy.
ABSTRACT
@#Currently the available therapies cannot satisfy all the clinical requirements, therefore advanced technologies are urgently demanded. Delivery system the polymeric prodrug based has both advantages of prodrug strategy and nanoparticle drug delivery strategy. The system can improve the drug bioavailability, enhance the drug stability, and make the drug targeting system more effective. The system can reduce the side effects and improve the therapeutic effect of drug. According to the mechanism of this drug system, passive targeting, active targeting, triggered release and co-administration were reviewed. Finally, the research prospects and issues in this field were pointed out.
ABSTRACT
Tumor-associated fibroblasts(TAFs),the most important stromal cells of the tumor microenvironment (TME),have been found to support tumorigenesis and tumor metastasis in a variety of ways,including paracrine, direct contact with cells,immune regulation and extracellular matrix remolding.Therefore,TAFs in the TME have been an optimal target for cancer therapy.In this review,the TAFs targeted therapies are summarized to provide the new strategy for tumor treatments based on the analysis of the location and specific biological phenotypes of TAFs in tumors.
ABSTRACT
From drug repurposing studies, this work aimed to evaluate the activity of different pyrazinoic acid (POA) derivatives against Sporothrix brasiliensis. The POA esters were prepared and characterized as previously reported by classical esterification reactions, with good to excellent yields. Sporothrix brasiliensis isolates from cats (n=6) and standard strains of S. brasiliensis and S. schenckii were used to assess the antifungal activity of the POA derivatives through broth microdilution assay (CLSI M38-A2). Among the tested compounds, molecules 3 and 4 showed fungistatic and fungicidal activities against all Sporothrix spp. strains, and the obtained MIC and MFC values ranged from 2.12 to 4.24 mg/mL and from 1.29 to 5.15 mg/mL, respectively. Compound 2 and 5 were active as in vitro inhibitors of fungal growth, but showed weak fungicidal activity, while molecules 1 and POA itself were inactive. The results suggest the activity of POA derivatives against Sporothrix spp. may be dependent on the lipophilicity. In addition, the antifungal susceptibility of the isolates to itraconazole was performed, showing that two Sporothrix isolates from cats were itraconazole-resistant. Compounds 3 and 4 were also active against these itraconazole-resistant isolates, indicating a possible alternative route to the standard mode of action of itraconazole.
Subject(s)
Animals , Male , Female , Cats , Sporotrichosis/drug therapy , Sporothrix/classification , Prodrugs , Itraconazole/analysis , Antifungal AgentsABSTRACT
Hydrogen sulfide (H2S) is recognized as one of three gasotransmitters together with nitric oxide (NO) and carbon monoxide (CO). As a signaling molecule, H2S plays an important role in physiology and shows great potential in pharmaceutical applications. Along this line, there is a need for the development of H2S prodrugs for various reasons. In this review, we summarize different H2S prodrugs, their chemical properties, and some of their potential therapeutic applications.
ABSTRACT
A natural prodrug is a chemical compound or substance obtained from plants, microorganism, animal and marine sources. Natural products are small molecule source for Food and Drug Administration approved drugs and major sources for drug discovery. Most of the drugs for different ailment diseases undergo first pass metabolism, resulting in drug inactivation and the generation of toxic metabolites in body. Enormous numbers of prodrugs naturally present in plants, microorganism, animal and marine sources and those prodrugs undergoes chemical reaction to form non-toxic compounds. This review summarizes the list of prodrugs naturally present in the natural product.
ABSTRACT
A natural prodrug is a chemical compound or substance obtained from plants, microorganism, animal and marine sources. Natural products are small molecule source for Food and Drug Administration approved drugs and major sources for drug discovery. Most of the drugs for different ailment diseases undergo first pass metabolism, resulting in drug inactivation and the generation of toxic metabolites in body. Enormous numbers of prodrugs naturally present in plants, microorganism, animal and marine sources and those prodrugs undergoes chemical reaction to form non-toxic compounds. This review summarizes the list of prodrugs naturally present in the natural product.
ABSTRACT
A latenciação é uma importante ferramenta no processo de desenvolvimento de fármacos, pois através dela, diversas barreiras biológicas que limitam o uso de um agente terapêutico podem ser superadas. Assim, esta estratégia permite a reintrodução de substâncias anteriormente descartadas por suas propriedades indesejáveis e o aprimoramento de novos fármacos, antes mesmo que sejam lançados na terapêutica. Embora a latenciação apresente vantagens clínicas, não existem estudos demonstrando a vantagem econômica do uso de pró-fármacos em relação às substâncias precursoras. Dessa forma, o objetivo do presente trabalho foi elaborar um perfil comparativo do custo do tratamento entre pró-fármacos e seus respectivos fármacos precursores, disponíveis no mercado farmacêutico brasileiro, visando demonstrar a real importância da latenciação como ferramenta norteadora para o desenvolvimento de fármacos e, principalmente, a viabilidade financeira do uso de pró-fármacos. Constatou-se que seis do total de pró-fármacos analisados apresentaram-se financeiramente mais vantajosos que os seus precursores e, mesmo para os pró-fármacos que tiveram custo mais elevado, a vantagem clínica alcançada justifica sua utilização.
Prodrug design is an important tool in the drug discovery process, since many biological barriers that limit the use of a drug may be overcome by a prodrug precursor. This strategy allows the improvement of new drugs before they are marketed and also enables the reintroduction of substances previously discarded for their undesirable properties. Although clinical advantages of prodrug design are well-established, there are no studies demonstrating the economic benefits of using prodrugs rather than the intended drugs. The aim of this study was to elaborate a technical report on the relative cost of treatments carried out with prodrugs or with the related drugs. This study was intended to demonstrate the real importance of prodrug design as a guiding tool for drug development and the financial viability of the use of prodrugs. It was found that six of the analyzed prodrugs were financially advantageous compared to the actual drugs and that, even for the prodrugs that had a higher cost, the clinical advantage justified their therapeutic use.
Subject(s)
Health Care Costs , Pharmaceutical Preparations/chemical synthesis , Reaction TimeABSTRACT
Histone deacetylase (HDAC) has been highlighted as one of key players in tumorigenesis and angiogenesis. Recently, several derivatives of psammaplin (Psams) from a marine sponge have been known to inhibit the HDAC activity, but the molecular mechanism for the inhibition has not fully understood. Here, we explored the mode of action of Psams for the inhibition of HDAC activity in the molecular and cellular level. Among the derivatives, psammaplin A (Psam A) showed the potent inhibitory activity in enzyme assay and anti-proliferation assay with IC50 value of 0.003 and 1 microM, respectively. Psam A selectively induced hyperacetylation of histones in the cells, resulting in the upregulation of gelsolin, a well-known HDAC target gene, in a transcriptional level. In addition, reduced Psam A showed a stronger inhibitory activity than that of non-reduced one. Notably, glutathione-depleted cells were not sensitive to Psam A, implying that cellular reduction of the compound is responsible for the HDAC inhibition of Psam A after uptake into the cells. Together, these data demonstrate that Psam A could exhibit its activity under the reduced condition in the cells and be a new natural prodrug targeting HDAC.