Efficacy of the hypoxia-activated prodrug evofosfamide (TH-302) in nasopharyngeal carcinoma in vitro and in vivo

Background:Tumor hypoxia is considered an important factor in metastasis and disease relapse.Evofosfamide is a hypoxia-activated prodrug that selectively targets the hypoxic regions of solid tumors.As hypoxia-inducible factor-1α(HIF-1α)is overexpressed in nasopharyngeal carcinoma(NPC)tissues,we performed the present study to evaluate the efficacy profile of evofosfamide in NPC.Methods:We evaluated the efficacy of evofosfamide as a single agent or combined with cisplatin(DDP)in the NPC cell lines CNE-2,HONE-1 and HNE-1,and in nude mouse xenograft tumor models.Results:Evofosfamide exhibited hypoxia-selective cytotoxicity in NPC cell lines,with 50%inhibition concentration(IC50)values of 8.33±0.75,7.62±0.67,and 0.31±0.07μmol/L under hypoxia in CNE-2,HONE-1 and HNE-1 cells,respectively.The sensitization ranged from ninefold to greater than 300-fold under hypoxia compared with normoxia controls.The combination of evofosfamide with DDP had a synergistic effect on cytotoxicity in the NPC cell lines by combination index values assessment.Cell cycle G2 phase was arrested after treated with 0.05μmol/L evofosfamide under hypoxia.Histone H2AX phosphorylation(γH2AX)(a marker of DNA damage)expression increased while HIF-1αexpression suppressed after evofosfamide treatment under hypoxic conditions.In the HNE-1 NPC xenograft models,evofosfamide exhibited antitumor activity both as a single agent and combined with DDP.Hypoxic regions in xeno-graft tissue were reduced after both evofosfamide monotherapy and combined therapy with DDP.Conclusions:Our results present preclinical evidence for targeting the selective hypoxic portion of NPC by evofosfa-mide as a single agent and combined with DDP and provide rationale for the potential clinical application of evofosfa-mide for the treatment of nasopharyngeal carcinoma.

Exploring Ester Prodrugs: A Comprehensive Review of Approaches, Applications, and Methods

The review provides an overview of the approaches, applications, and methods for ester prodrugs. Ester prodrugs are pharmacologically inactive compounds in their original form but become active drugs on biotransformation within the body, which offers advantages concerning the solubility, stability, and targeted delivery of the active drug. Several approaches of ester prodrugs have been reviewed in this review, including simple ester prodrugs, amino acid ester prodrugs, sugar ester prodrugs, lipid ester prodrugs, and polymeric ester prodrugs. This review incorporates in vitro and in vivo methods as well as the characterization of physical and chemical properties for ester prodrugs, cell culture systems, enzymatic assays, and animal models—all of these having a very important bearing on the evaluation of stability, bioavailability, and efficacy for ester prodrugs. While the benefits of using ester prodrugs are significant, there are also disadvantages like instability, poor or variable enzymatic hydrolysis, and toxicity from released promoieties or by-products. This review discusses solutions to the various limitations that include enhancing stability with ionizable promoieties and using physiologically-based pharmacokinetic modeling. The review also highlights the application of ester prodrugs in neurological disorders, such as Parkinson’s disease, and the ongoing efforts to address the critical limitations in treatment efficacy. Future prodrug strategies are poised to advance significantly by harnessing diverse transport mechanisms across the blood-brain barrier and integrating nanotechnology.

Glucocorticoids-based prodrug design:Current strategies and research progress

Attributing to their broad pharmacological effects encompassing anti-inflammation,antitoxin,and immunosuppression,glucocorticoids(GCs)are extensively utilized in the clinic for the treatment of diverse diseases such as lupus erythematosus,nephritis,arthritis,ulcerative colitis,asthma,keratitis,macular edema,and leukemia.However,longterm use often causes undesirable side effects,including metabolic disorders-induced Cushing's syndrome(buffalo back,full moon face,hyperglycemia,etc.),osteoporosis,aggravated infection,psychosis,glaucoma,and cataract.These notorious side effects seriously compromise patients'quality of life,especially in patients with chronic diseases.Therefore,glucocorticoid-based advanced drug delivery systems for reducing adverse effects have received extensive attention.Among them,prodrugs have the advantages of low investment,low risk,and high success rate,making them a promising strategy.In this review,we propose the strategies for the design and summarize current research progress of glucocorticoid-based prodrugs in recent decades,including polymer-based prodrugs,dendrimer-based prodrugs,antibody-drug conjugates,peptide-drug conjugates,carbohydrate-based prodrugs,aliphatic acid-based prodrugs and so on.Besides,we also raise issues that need to be focused on during the development of glucocorticoid-based prodrugs.This review is expected to be helpful for the research and development of novel GCs and prodrugs.

Synergistic enhancement of ultrasound therapy for tumors using hypoxia-activated 6-diazo-5-oxo-L-norleucine(DON)prodrug nanoparticles

Ultrasound(US)has been applied in clinical practice for its non-invasive and high selectivity.However,it is difficult to achieve a satisfactory anti-tumor effect with US alone.Meanwhile,the use of US therapy alone can exacerbate tumor hypoxia.In this study,we prepared hypoxia-activated 6-diazo-5-oxo-L-norleucine(DON)prodrug nanoparticles(HDON-NPs)to improve US therapeutic effects.In an H22 murine liver cancer model,US therapy selectively disrupted tumor blood vessels,leading to increased tumor hypoxia and a 1.67-fold increase in the expression of nitroreductase(NTR).The combination therapy of US and HDON-NPs demonstrated a synergistic effect,resulting in a tumor suppression rate(TSR)of 90.2%±6.4%,which was 5.93-fold higher than that of US therapy alone.The combined treatment selectively blocked the glutamine metabolism of the tumor cells while simultaneously activating the T cells in the tumor microenvironment,thereby exerting a robust anti-tumor effect.

A MXene-Based Bionic Cascaded-Enzyme Nanoreactor for Tumor Phototherapy/Enzyme Dynamic Therapy and Hypoxia-Activated Chemotherapy

The enzyme-mediated elevation of reactive oxygen species(ROS)at the tumor sites has become an emerging strategy for regulating intracellular redox status for anticancer treatment.Herein,we proposed a camouflaged bionic cascaded-enzyme nanoreactor based on Ti_(3)C_(2)nanosheets for combined tumor enzyme dynamic therapy(EDT),phototherapy and deoxygenation-activated chemotherapy.Briefly,glucose oxidase(GOX)and chloroperoxidase(CPO)were chemically conjugated onto Ti_(3)C_(2)nanosheets,where the deoxygenation-activated drug tirapazamine(TPZ)was also loaded,and the Ti_(3)C_(2)-GOX-CPO/TPZ(TGCT)was embedded into nanosized cancer cell-derived membrane vesicles with high-expressed CD47(m_eTGCT).Due to biomimetic membrane camouflage and CD47 overexpression,m_eTGCT exhibited superior immune escape and homologous targeting capacities,which could effectively enhance the tumor preferential targeting and internalization.Once internalized into tumor cells,the cascade reaction of GOX and CPO could generate HClO for efficient EDT.Simultaneously,additional laser irradiation could accelerate the enzymic-catalytic reaction rate and increase the generation of singlet oxygen(~1O_(2)).Furthermore,local hypoxia environment with the oxygen depletion by EDT would activate deoxygenation-sensitive prodrug for additional chemotherapy.Consequently,m_eTGCT exhibits amplified synergistic therapeutic effects of tumor phototherapy,EDT and chemotherapy for efficient tumor inhibition.This intelligent cascaded-enzyme nanoreactor provides a promising approach to achieve concurrent and significant antitumor therapy.

Triphenylmethanol Conjugates of Triptorelin as Cell-Penetrating Anti-Cancer Prodrugs

Some Triptorelin® (TRP) conjugates of triphenylmethanol derivatives (TPMs) with optimized hydrophobicity were synthesized by reacting 2-substituted methoxy benzenes with 1,3,5-trioxane, followed by the conjugation with TRP and sebacic acid to produce TRP-TPMs derivatives. Comparative antiproliferative assays between TRP-TPMs conjugates and the corresponding non-covalent physical mixtures of the TPMs derivatives and TRP were used to treat human acute lymphoblastic leukemia (CCRF-CEM), human ovarian adenocarcinoma (SK-OV-3) and mouse preadipocytes (3T3-L1) cells. TRP-TPMs conjugates at the 50 μM inhibited cell proliferation in CCRF-CEM, SK-OV-3 and 3T3-L1 cells by 21% - 37%, 24% - 73%, 37% - 56%, respectively following incubation for 72 h. These findings indicate that TRP-TPMs derivatives have the potential to enhance the biological activity of TRP.

基于点击化学的酸敏感性聚合物前药的设计与合成

基于点击化学反应,将姜黄素和己烷-1,6-二丙炔酸二酯直接共聚,制备了酸敏感性主链型聚合物前药,并采用紫外可见吸收光谱法、荧光光谱法、红外光谱法、扫描电子显微镜、粒径分布及Zeta电位对其结构进行了表征。结果表明,聚合物前药为粒径100~200 nm的球形纳米粒子,形状均匀,分散性良好;聚合物前药在肿瘤微环境下通过酸触发聚合物主链降解,实现对药物的可控性释放。为提升常规化疗药物疗效并降低其毒副作用研究提供了参考。

载磺胺嘧啶聚乙二醇前药的制备及抗菌性能研究

以不同分子量的聚乙二醇(PEG)与一氯乙酸为原料,通过酯化反应合成氯乙酰聚乙二醇酯,将它与抗菌剂磺胺嘧啶(SD)结合制备了不同分子量的PEG-SD前药,并进行了红外、核磁和紫外的表征。结果表明,磺胺嘧啶成功接载到聚乙二醇链末端。随着聚乙烯醇的分子量降低,其酯化程度增加,接负SD的比例增加。水解实验表明,PEG-SD前药具有长效缓释抗菌的功能。随着分子量的降低,抑菌效果越好。PEG600-SD对大肠杆菌和金黄色葡萄球菌的最小抑菌浓度分别为31.25μg·mL^(-1)和15.62μg·mL^(-1),具有最好的抑菌效果。

熊果酸及其氨基酸酯前体药物在大鼠体内的药动学研究

目的 建立测定大鼠血浆中熊果酸浓度的超高效液相色谱串联质谱(UPLC-MS/MS)分析方法,探讨熊果酸及其氨基酸酯前体药物在大鼠体内的药动学变化。方法 取雄性大鼠,经口给药70 mg·kg^(-1)(以熊果酸含量计)的熊果酸原料药,熊果酸-维生素E琥珀酸聚乙二醇酯混合液,熊果酸苯丙氨酸肌氨酸酯盐酸盐-维生素E琥珀酸聚乙二醇酯溶液。采用沉淀蛋白法处理血浆样品,以塞来昔布作为内标,色谱柱为Acquity UPLC~? BEH C18(50 mm×2.1 mm, 1.7μm)柱,流动相为体积分数0.025%氨水乙腈-10 mmol·L^(-1)乙酸铵-体积分数0.1%氨水溶液(体积比70∶30),流速0.4 mL·min^(-1),采用大气压化学电离源,负离子多反应监测模式扫描。结果 血浆中熊果酸在质量浓度100~10 000μg·L^(-1)内线性良好。与原料药比较,熊果酸-维生素E琥珀酸聚乙二醇酯混合液组和熊果酸苯丙氨酸肌氨酸酯盐酸盐-维生素E琥珀酸聚乙二醇酯溶液组的熊果酸生物利用度分别提高了8.43倍和19.52倍(P<0.05)。结论 经口给药后熊果酸在大鼠体内的生物利用度较低,前体药物熊果酸苯丙氨酸肌氨酸酯可提高熊果酸的经口给药生物利用度。分析方法符合生物样品的测定要求,适用于大鼠血浆中熊果酸质量浓度的测定。

基于羟乙基淀粉-姜黄素前药的SN38协同给药胶束构建与评价

化疗药物协同给药可以作用于不同代谢通路,有效抑制癌细胞增殖,从而改善药物的治疗效果,在避免引发多药耐药性等方面具有显著优势。本研究基于季铵盐羟乙基淀粉-姜黄素(QHES-S-CUR)前药,构建了负载7-乙基-10-羟基喜树碱(SN38)的协同给药胶束SN38@QHES-S-CUR。首先,借助分子动力学模拟的手段预测姜黄素与SN38共混体系的稳定性;在此基础上,通过纳米沉淀法制备了负载SN38的协同给药胶束。详细考察了QHES-S-CUR与SN38的质量比对胶束形貌及粒径分布的影响,在QHES-S-CUR与SN38的质量比为20:1时,可得到平均粒径为(258.76±28.76)nm的球形纳米粒。体外药物释放实验表明,SN38@QHES-S-CUR胶束能够在模拟的肿瘤微环境中响应性地释放出姜黄素及SN38,比SN38单独给药对小鼠结肠癌细胞CT-26的细胞毒性显著增强。本研究将两亲性前药应用于疏水性化疗药物的递送中,为化疗药物的协同给药提供了新思路。

20-羟基黄体酮甘油三酯前药20-DHP-C5-TG的制备及其淋巴转运途径初探

目的制备20-羟基黄体酮甘油三酯前药(20-DHP-C5-TG),考察该前药经胃肠道吸收通过淋巴转运进入体循环的过程。方法以黄体酮为原料经还原、选择性氧化得到20-羟基黄体酮(20-DHP),对20-DHP进行亲脂性结构修饰,通过酯键将母药20-DHP与修饰基团连接,得到目标前药20-DHP-C5-TG,经IR、1 H-NMR、13 C-NMR对其进行结构表征。取大鼠腹腔注射环己酰亚胺建立乳糜微粒阻断模型,随机分为正常给药组(灌胃给予前药油溶液400 mg/kg体重)、淋巴阻断组(腹腔注射环己酰亚胺3 mg/kg体重,1 h后灌胃给予前药油溶液400 mg/kg体重),分别于给药后5 min、15 min、0.5 h、1 h、2 h、4 h、8 h、12 h取血,采用HPLC法测定正常给药组和淋巴阻断组的药时曲线下面积,计算淋巴转运比例。结果20-DHP和20-DHP-C5-TG均制备成功,产率分别为42%和44%。20α-DHP-C5-TG前药的淋巴转运比例为90.065%,20β-DHP-C5-TG前药的淋巴转运比例为84.950%。结论20-DHP-C5-TG前药在体内具有明显的淋巴转运趋势,入血后能够释放出母药。

纳米聚合物前药的设计合成及其抗乳腺癌的应用

癌症是全球重大的公共卫生问题。根据世界卫生组织国际癌症研究机构发布的全球癌症数据最新统计,女性乳腺癌位列全球第二,占新增病例总数的11.6%。乳腺癌常规治疗手段存在生物利用度低、毒副作用大和易产生耐药性等问题。纳米聚合物前药因其高载药率、低毒副作用、高效靶向性和实时可控性等独特的优势应运而生。总结了纳米聚合物前药的优势及分类,并从设计合成路线、刺激响应途径、主动靶向特性及其抗乳腺癌应用等方面进行了系统介绍,以便研究人员深入了解作用机制,从而进一步优化其设计和应用策略。此外还讨论了纳米聚合物前药在乳腺癌治疗中的前景与挑战,以期为纳米聚合物前药的临床应用提供有益借鉴。

MPEG-5-FU前药的合成与性能研究

以不同分子量的聚乙二醇单甲醚(MPEG)钠盐与1-(氯代乙酰)-5-氟尿嘧啶反应,通过威廉森反应合成了聚乙二醇单甲醚-5-氟尿嘧啶(MPEG-5-FU)前药,采用红外光谱,核磁氢谱,紫外光谱进行了表征,证明5-氟尿嘧啶单元已经成功接载到聚乙二醇链的末端;随着MPEG分子量的提高,前药的水溶性增强。水解实验结果表明MPEG-5-FU前药具有长效缓释的功能,可以在不同pH值的缓冲液中释放出5-FU,当MPEG的分子量达到2 000时,前药的水溶性和释药速率最大。

Supramolecular metallopolymer for hypoxia-activated ruthenium complexes delivery and smart chemo-photodynamic therapy

The Ru complexes have garnered a great deal of attention for antitumor phototherapy;however, achieving efficient cellular uptake and tumor-specific activation represents a major challenge. Herein, we synthesize a hypoxia-activated Ru complex(Ru ANM) and construct it into supramolecular polymers(Poly Ru ANM) through high binding affinity interaction. The amphiphilic supramolecular polymers possess self-assembly, resulting in the formation of diverse nanostructures exhibiting a range of morphologies by simply adjusting the host-guest ratio. As the polymer nanostructure size and morphology have been optimized, Poly Ru ANM prevents premature drug leakage and accumulates rapidly in the tumor cells. In the tumor hypoxia microenvironment, the polymer undergoes selective activation and disintegration, leading to the unlock of Ru complexes.Notably, the subsequent application of red light irradiation exacerbates the hypoxia and potentiates the liberation of the Ru complexes. This polymer design concept provides some novel insights into on-demand drug delivery and smart chemophotodynamic therapy.

Charge adaptive phytochemical-based nanoparticles for eradication of methicillin-resistant staphylococcus aureus biofilms

The intrinsic resistance of MRSA coupled with biofilm antibiotic tolerance challenges the antibiotic treatment of MRSA biofilm infections.Phytochemical-based nanoplatform is a promising emerging approach for treatment of biofilm infection.However,their therapeutic efficacy was restricted by the low drug loading capacity and lack of selectivity.Herein,we constructed a surface charge adaptive phytochemical-based nanoparticle with high isoliquiritigenin(ISL)loading content for effective treatment of MRSA biofilm.A dimeric ISL prodrug(ISL-G2)bearing a lipase responsive ester bond was synthesized,and then encapsulated into the amphiphilic quaternized oligochitosan.The obtained ISL-G2loaded NPs possessed positively charged surface,which allowed cis-aconityl-D-tyrosine(CA-Tyr)binding via electrostatic interaction to obtain ISL-G2@TMDCOS-Tyr NPs.The NPs maintained their negatively charged surface,thus prolonging the blood circulation time.In response to low pH in the biofilms,the fast removal of CA-Tyr led to a shift in their surface charge from negative to positive,which enhanced the accumulation and penetration of NPs in the biofilms.Sequentially,the pH-triggered release of D-tyrosine dispersed the biofilm and lipase-triggered released of ISL effectively kill biofilm MRSA.An in vivo study was performed on a MRSA biofilm infected wound model.This phytochemical-based system led to~2log CFU(>99%)reduction of biofilm MRSA as compared to untreated wound(P<0.001)with negligible biotoxicity in mice.This phytochemical dimer nanoplatform shows great potential for long-term treatment of resistant bacterial infections.

Targeting AMPKa1 Gene in PC3 Cells by Triphenylmethanol Derivatives

Epidemiological studies indicate that treatment with metformin, an AMP-activated protein kinase (AMPK) activator, reduces the incidence of cancers. Activation of AMPK has also been reported to oppose tumor progression in diverse types of cancers and offers promising cancer therapy. Furthermore, AMPK is a primary regulator of energy metabolism and has also been implicated in cell cycle progression, angiogenesis, cell transformation, migration, and cancer. We have recently synthesized novel flavonoids, namely, triphenylmethanol derivatives (TPMs), but the effectiveness of the TPMs on the activity of AMPK remains unclear. We hypothesized that the novel TPMs would inhibit cancer cell proliferation through the activation of AMPK isoforms in cells. The effects of TPMs on prostate cells (PC-3) were investigated. Cells were exposed to TPMs for either 12 or 24 hr. at the respective doses of 0, 25, 50 100, and 200 µM based on the cell viability studies by the (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, a tetrazole) (MTT) assay. The results indicate that cells exposed to the respective doses of TPMs increased both phospho- and total-AMPKα1 in a dose- and time-dependent manner. The effects of the increases for the phospho- and total-AMPKα in cells were greater for the 24-hr than the 12-hr. incubation. Further studies are currently going on to elucidate the specificities of the said insults in increasing the phospho- and total-AMPKα activities and for the other respective isoforms.

紫杉醇棕榈酸酯的合成及其脂质体的制备与处方研究

目的通过对紫杉醇(PTX)的结构改造联合相应脂质体的构建,改善肿瘤细胞摄取,增加药物疗效。方法通过酯化反应制备了紫杉醇前药PTX-PA,并建立含量方法学研究。采用单因素筛选,结合粒径、包封率等指标评价不同方法、条件下制备的PTX-PA/Lip,确定其最佳处方和制备工艺。结果通过酯化反应成功制备PTX-PA,且建立的HPLC定量分析方法符合方法学要求。利用单因素筛选,确定了PTX-PA/Lip的最佳处方和制备工艺,通过最优处方制备的PTX-PA/Lip纳米粒径为(2.75±1.81)nm,PDI为(0.076±0.020),药物包封率达到90%以上。结论基于纳米技术成功制备出棕榈酸修饰的紫杉醇脂质体,增强了紫杉醇在靶细胞的递送,为PTX-PA的药效学研究奠定基础。

雷公藤内酯醇乏氧激活前药的合成与结构表征

(目的)制备雷公藤内酯醇乏氧激活前药,并对其结构进行表征;合成了Gem1和Dox1。总计合成了三个乏氧激活前药,用于后续抗肿瘤实验研究。(方法)2-硝基咪唑通过亲核取代反应,水解反应得到3-(2-硝基-1H-咪唑-1-基)丙酸。3-(2-硝基-1H-咪唑-1-基)丙酸再与雷公藤内酯醇、多柔比星和吉西他滨通过缩合反应得到目标化合物——Gem1和Dox1,采用核磁共振氢谱和高分辨质谱确认其结构。(结果)成功得到目标化合物——Gem1和Dox1。(结论)研究采用核磁共振氢谱和高分辨质谱确认了目标化合物——Gem1和Dox1的结构,成功合成的三个乏氧激活前药,为后续抗肿瘤研究奠定基础。

Cytochrome P450 Directed Prodrug Activation Therapy in Research of Cancer Enzymology

Cancer enzymology is a promising filiation of bio-medical sciences. In thepast decades, enzymes, such as GST(glutathione S-transferase) , PKC(protein kinase C) , Topo(DNAtopoisomerases), TK(tyrosine kinase), CD (bacterial cytosine deaminase), CPG2(carboxypeptidase G2) ,and PNP (purine nucleoside phosphorylase), have been known to bear close relations to cancer. Theirspecific expression and influence on the process of tumor initiation, promotion and progressionattract scientists to apply them as a biochemical marker of certain malignant tumor, a predictor ofresponse in cancer chemotherapy; to apply them to drug design, tumor prevention and as adjuvant toradiotherapy or surgery.

以苯硼酸为载体的前药及其类似物的研究进展

ROS是机体重要的信号分子,对机体的代谢过程中起着重要的作用。研究发现,在癌症、炎症和神经退行性疾病等疾病组织出现了ROS异常升高的现象。这一现象为治疗以上相关疾病提供了靶点,ROS型敏感型前药应运而生,近年来将苯硼酸基团作为载体引入原药中设计ROS敏感型前药成为基于ROS开发新药的有效途径。本文作者对近年来开发出含苯硼酸结构的前药的设计思路及药效进行综述,所涉及的药物包括传统的化疗药物,生物小分子以及光动力疗法的光敏剂。以上药物均有良好的疗效,但此类前药也面临一些问题。本文作者探讨了这类前药连接臂的选择、合成方法以及释放效果等相关问题。希望为设计更好更合理含苯硼酸结构的前药和提出新的思路。