UTP23基因在上皮性卵巢癌紫杉醇耐药细胞中的表达及对紫杉醇化疗耐药的影响

目的: 探讨UTP23基因在上皮性卵巢癌紫杉醇耐药细胞中的表达及对紫杉醇化疗耐药的影响。方法: 采用逆转录聚合酶链式反应（RT-PCR）和蛋白免疫印迹（Western blot）法检测上皮性卵巢癌紫杉醇耐药细胞中UTP23、P-糖蛋白（P-gp）、多药耐药基因（MDR1）的mRNA表达水平,使用特异性UTP23-siRNA转染上皮性卵巢癌紫杉醇耐药细胞,使用RT-PCR和 Western blot法检测转染后UTP23、P-gp、MDR1基因的表达,使用MTT法检测UTP23-siRNA对上皮性卵巢癌紫杉醇耐药细胞生长的影响及耐药性。结果: 耐药组UTP23基因mRNA表达水平明显低于敏感组（P<0.05）,耐药组P-gp、MDR1基因mRNA表达水平明显高于敏感组（P<0.05）;转染组与未转染组、阴性对照组相比较,UTP23 mRNA水平明显升高（P<0.05）, 未转染组与阴性对照组相比较,UTP23 mRNA水平和蛋白水平差异无统计学意义（P>0.05）;转染组与未转染组、阴性对照组相比较,P-gp、MDR1 mRNA表达水平明显下降,差异有统计学意义（P<0.05）,未转染组与阴性对照组相比较,P-gp、MDR1 mRNA表达水平无明显变化,差异无统计学意义（P>0.05）; 紫杉醇对UTP23-siRNA转染后上皮性卵巢癌耐药细胞的IC50浓度明显高于未转染组和阴性对照组（P<0.05）。结论: UTP23基因在上皮性卵巢癌紫杉醇耐药细胞中低表达,其可能通过间接调控MDR1及P-gp的表达而参与上皮性卵巢癌紫杉醇细胞对紫杉醇的耐药。     

每周脂质体紫杉醇联合替吉奥对老年晚期胃癌患者血清肿瘤标志物与可溶性E-钙黏连蛋白的影响

目的:分析每周脂质体紫杉醇联合替吉奥对老年晚期胃癌患者血清肿瘤标志物与可溶性E-钙黏连蛋白（sEC）影响。方法:87例老年晚期胃癌患者按随机数字表法分为41例对照组和46例试验组。对照组奥利沙铂每次130 mg/m2,静脉滴注,每周期第1天,1个疗程为21 d,持续治疗3个疗程;替吉奥每次50 mg（体表面积>1.25 m-2～1.5 m-2）或者60 mg（体表面积≥1.5 m-2）,口服,每周期第1～28天,6周1个疗程,持续治疗2个疗程。试验组替吉奥用法同对照组,脂质体紫杉醇每次60 mg/m2,静脉滴注,每周期第1、8、15、22天,1个疗程为6周。比较两组临床疗效,治疗前后血清肿瘤标志物、sEC水平,不良反应及生存情况分析。结果:治疗后,试验组和对照组疾病控制率分别为65.22%（30例次/46例次）和56.10%（23例次/41例次）,1年生存率分别为58.69%（27例次/46例次）和48.78%（20例次/41例次）,比较无统计学差异（P>0.05）。试验组和对照组血清癌胚抗原（CEA）水平分别为（9.37±2.03）和（8.99±1.48）ng/mL,糖类抗原125（CA125）分别为（24.08±3.98）和（23.22±3.86）U/mL、糖链抗原19-9（CA19-9）分别为（14.57±2.81）和（15.30±2.22）U/mL,sEC分别为（1 903.87±250.17）和（1 934.37±199.46）ng/mL,比较无统计学差异（P>0.05）。两组不良反应以恶心呕吐、贫血、血小板减少、粒细胞减少、腹泻及肝肾功能异常为主,组间各不良反应发生率比较有统计学差异（P<0.05）。结论:每周脂质体紫杉醇联合替吉奥对老年晚期胃癌患者的效果确切,可降低血清肿瘤标志物和sEC水平,且患者耐受性较好。     

Three-Dimensional Collagen Type I Matrix Up-Regulates Nuclear Isoforms of the Microtubule Associated Protein Tau Implicated in Resistance to Paclitaxel Therapy in Ovarian Carcinoma

Epithelial ovarian carcinoma is the deadliest gynecologic malignancy. One reason underlying treatment failure is resistance to paclitaxel. Expression of the microtubule associated protein tau has recently been proposed as a predictor of response to paclitaxel in ovarian carcinoma patients. Expression of tau was probed using immunohistochemistry in 312 specimens of primary, and 40 specimens of metastatic, ovarian carcinoma. Serous epithelial ovarian carcinoma cell line models were used to determine the expression of tau by Western blot and immunofluorescence staining. Subcellular fractionation and Western blot were employed to examine nuclear and cytoplasmic localization of tau. Gene silencing and clonogenic assays were used to evaluate paclitaxel response. Tau was expressed in 44% of all tested cases. Among the primary serous epithelial ovarian carcinoma cases, 46% were tau-positive. Among the metastatic serous epithelial ovarian carcinomas, 63% were tau-positive. Cell culture experiments demonstrated that tau was expressed in multiple isoforms. Three-dimensional collagen I matrix culture conditions resulted in up-regulation of tau protein. Silencing of tau with specific siRNAs in a combination with three-dimensional culture conditions led to a significant decrease of the clonogenic ability of cells treated with paclitaxel. The data suggest that reduction of tau expression may sensitize ovarian carcinoma to the paclitaxel treatment.     

聚乳酸类载紫杉醇纳米粒表面修饰的研究进展

聚乳酸/聚乳酸-羟基乙酸载紫杉醇纳米粒具有良好的缓释和靶向性能。本文总结目前最常用的制备方法,重点阐述载紫杉醇聚乳酸/聚乳酸-羟基乙酸纳米粒的表面修饰和特点。简要探讨了载紫杉醇聚乳酸/聚乳酸-羟基乙酸纳米粒未来的发展方向。     

Self-Assembly of pH-Labile Polymer Nanoparticles for Paclitaxel Prodrug Delivery: Formulation,Characterization, and Evaluation

The efficacy of paclitaxel (PTX) is limited due to its poor solubility, poor bioavailability, and acquired drug resistance mechanisms. Designing paclitaxel prodrugs can improve its anticancer activity and enable formulation of nanoparticles. Overall, the aim of this work is to improve the potency of paclitaxel with prodrug synthesis, nanoparticle formation, and synergistic formulation with lapatinib. Specifically, we improve potency of paclitaxel by conjugating it to α-tocopherol (vitamin E) to produce a hydrophobic prodrug (Pro); this increase in potency is indicated by the 8-fold decrease in half maximal inhibitory concentration (IC₅₀) concentration in ovarian cancer cell line, OVCA-432, used as a model system. The efficacy of the paclitaxel prodrug was further enhanced by encapsulation into pH-labile nanoparticles using Flash NanoPrecipitation (FNP), a rapid, polymer directed self-assembly method. There was an 1100-fold decrease in IC₅₀ concentration upon formulating the prodrug into nanoparticles. Notably, the prodrug formulations were 5-fold more potent than paclitaxel nanoparticles. Finally, the cytotoxic effects were further enhanced by co-encapsulating the prodrug with lapatinib (LAP). Formulating the drug combination resulted in synergistic interactions as indicated by the combination index (CI) of 0.51. Overall, these results demonstrate this prodrug combined with nanoparticle formulation and combination therapy is a promising approach for enhancing paclitaxel potency.     

Effects of Anti-Cancer Drug Sensitivity-Related Genetic Differences on Therapeutic Approaches in Refractory Papillary Thyroid Cancer

Thyroid cancer (TC) includes tumors of follicular cells; it ranges from well differentiated TC (WDTC) with generally favorable prognosis to clinically aggressive poorly differentiated TC (PDTC) and undifferentiated TC (UTC). Papillary thyroid cancer (PTC) is a WDTC and the most common type of thyroid cancer that comprises almost 70–80% of all TC. PTC can present as a solid, cystic, or uneven mass that originates from normal thyroid tissue. Prognosis of PTC is excellent, with an overall 10-year survival rate >90%. However, more than 30% of patients with PTC advance to recurrence or metastasis despite anti-cancer therapy; consequently, systemic therapy is limited, which necessitates expansion of improved clinical approaches. We strived to elucidate genetic distinctions due to patient-derived anti-cancer drug-sensitive or -resistant PTC, which can support in progress novel therapies. Patients with histologically proven PTC were evaluated. PTC cells were gained from drug-sensitive and -resistant patients and were compared using mRNA-Seq. We aimed to assess the in vitro and in vivo synergistic anti-cancer effects of a novel combination therapy in patient-derived refractory PTC. This combination therapy acts synergistically to promote tumor suppression compared with either agent alone. Therefore, genetically altered combination therapy might be a novel therapeutic approach for refractory PTC.     

Pirfenidone Sensitizes NCI-H460 Non-Small Cell Lung Cancer Cells to Paclitaxel and to a Combination of Paclitaxel with Carboplatin

Pirfenidone, an antifibrotic drug, has antitumor potential against different types of cancers. Our work explored whether pirfenidone sensitizes non-small cell lung cancer (NSCLC) cell lines to chemotherapeutic treatments. The cytotoxic effect of paclitaxel in combination with pirfenidone against three NSCLC cell lines (A549, NCI-H322 and NCI-H460) was evaluated using the sulforhodamine B assay. The effects of this combination on cell viability (trypan blue exclusion assay), proliferation (BrdU incorporation assay), cell cycle (flow cytometry following PI staining) and cell death (Annexin V-FITC detection assay and Western blot) were analyzed on the most sensitive cell line (NCI-H460). The cytotoxic effect of this drug combination was also evaluated against two non-tumorigenic cell lines (MCF-10A and MCF-12A). Finally, the ability of pirfenidone to sensitize NCI-H460 cells to a combination of paclitaxel plus carboplatin was assessed. The results demonstrated that pirfenidone sensitized NCI-H460 cells to paclitaxel treatment, reducing cell growth, viability and proliferation, inducing alterations in the cell cycle profile and causing an increase in the % of cell death. Remarkably, this combination did not increase cytotoxicity in non-tumorigenic cells. Importantly, pirfenidone also sensitized NCI-H460 cells to paclitaxel plus carboplatin. This work highlights the possibility of repurposing pirfenidone in combination with chemotherapy for the treatment of NSCLC.     

Salvage Chemotherapy with Cisplatin,Ifosfamide, and Paclitaxel in Aggressive Variant of Metastatic Castration-Resistant Prostate Cancer

Significant progress has been achieved in the treatment of metastatic castration-resistant prostate cancer (mCRPC). However, results in patients with aggressive variant prostate cancer (AVPC) have been disappointing. Here, we report retrospectively collected data from intensively pretreated AVPC patients (n = 17; 88.2% visceral metastases; 82% elevation of neuroendocrine markers) treated with salvage chemotherapy consisting of cisplatin, ifosfamide, and paclitaxel (TIP). At the interim analysis, 60% of patients showed radiographic response or stable disease (PFS = 2.5 months; OS = 6 months). In men who responded to chemotherapy, an OS > 15 months was observed. Preclinical analyses confirmed the high activity of the TIP regimen, especially in docetaxel-resistant prostate cancer cells. This effect was primarily mediated by increased cisplatin sensitivity in the emergence of taxane resistance. Proteomic and functional analyses identified a lower DNA repair capacity and cell cycle machinery deficiency to be causative. In contrast, paclitaxel showed inconsistent effects, partially antagonizing cisplatin and ifosfamide in some AVPC models. Consequently, paclitaxel has been excluded from the TIP combination for future patients. In summary, we report for the first time the promising efficacy of TIP as salvage therapy in AVPC. Our preclinical data indicate a pivotal role for cisplatin in overcoming docetaxel resistance.     

Branched Poly(ε-caprolactone)-Based Copolyesters of Different Architectures and Their Use in the Preparation of Anticancer Drug-Loaded Nanoparticles

Limitations associated with the use of linear biodegradable polyesters in the preparation of anticancer nano-based drug delivery systems (nanoDDS) have turned scientific attention to the utilization of branched-chain (co-)polymers. In this context, the present study evaluates the use of novel branched poly(ε-caprolactone) (PCL)-based copolymers of different architectures for the preparation of anticancer nanoparticle (NP)-based formulations, using paclitaxel (PTX) as a model drug. Specifically, three PCL-polyol branched polyesters, namely, a three-arm copolymer based on glycerol (PCL-GLY), a four-arm copolymer based on pentaerythritol (PCL-PE), and a five-arm copolymer based on xylitol (PCL-XYL), were synthesized via ring-opening polymerization and characterized by proton nuclear magnetic resonance (¹H-NMR), gel permeation chromatography (GPC), intrinsic viscosity, differential scanning calorimetry (DSC), X-ray diffraction (XRD), and Fourier-transform infrared (FT-IR) spectroscopy and cytotoxicity. Then, PTX-loaded NPs were prepared by an oil-in-water emulsion. The size of the obtained NPs varied from 200 to 300 nm, while the drug was dispersed in crystalline form in all formulations. High encapsulation efficiency and high yields were obtained in all cases, while FTIR analysis showed no molecular drug polymer. Finally, in vitro drug release studies showed that the studied nanocarriers significantly enhanced the dissolution rate and extent of the drug.