Breast cancer drugs perturb fundamental vascular functions of endothelial cells by attenuating protein S-nitrosylation

Cardiovascular side effects of broadly used chemotherapeutic drugs such as Tamoxifen citrate (TC), Capecitabine (CP) and Epirubicin (EP) among cancer survivors are well established. Nitric oxide (NO) is known to protect cardiovascular tissues under conditions of stress. NO can act through cyclic guanosine monophosphate (cGMP)-dependent and -independent pathways. Particularly, the S-nitrosylation of SH-groups in a protein by NO falls under cGMP-independent effects of NO. TC, CP, and EP are hypothesized as interfering with cellular protein S-nitrosylation, which, in turn, may lead to endothelial dysfunctions. The results show that all three drugs attenuate nitrosylated proteins in endothelial cells. A significant reduction in endogenous S-nitrosylated proteins was revealed by Saville–Griess assay, immunofluorescence and western blot. Incubation with the drugs causes a reduction in endothelial migration, vasodilation and tube formation, while the addition of S-nitrosoglutathione (GSNO) has a reversal of this effect. In conclusion, results indicate the possibility of decreased cellular nitrosothiols as being one of the reasons for endothelial dysfunctions under TC, CP and EP treatment. Identification of the down-regulated S-nitrosylated proteins so as to correlate their implications on fundamental vascular functions could be an interesting phenomenon.     

Docetaxel and epirubicin compared with docetaxel and prednisone in advanced castrate-resistant prostate cancer: a randomised phase II study

Background:

This randomised phase II study compared the activity and safety of the combination docetaxel (D)/epirubicin (EPI) with the conventional treatment D/prednisone (P) in advanced castrate-resistant prostate cancer (CRPC) patients.

Materials and methods:

Patients were randomly assigned to D 30 mg m⁻² as intravenous infusion (i.v.) and EPI 30 mg m⁻² i.v. every week (D/EPI arm), or D 70 mg m⁻² i.v. every 3 weeks and oral P 5 mg twice daily (D/P arm). Chemotherapy was administered until disease progression or unacceptable toxicity.

Results:

A total of 72 patients were enrolled in the study and randomly assigned to treatment: 37 to D/EPI and 35 to D/P. The median progression-free survival (PFS) was 11.1 months (95% CI 9.2–12.6 months) in the D/EPI arm and 7.7 months (95% CI 5.7–9.4 months) in the D/P arm (P=0.0002). The median survival was 27.3 months (95% CI 22.1–30.8 months) in the D/EPI arm and 19.8 months (95% CI 14.4–24.8 months) in the D/P arm (P=0.003). Both regimens were generally well tolerated.

Conclusion:

The treatment of advanced CRPC with weekly D combined with weekly EPI was feasible and tolerable, and led to superior PFS than the treatment with 3-weekly D and oral P.     

Chemotherapy with Cisplatin,Epirubicin, Methotrexate in the Treatment of Locally Advanced or Metastatic Transitional Cell Cancer of the Bladder (TCC)

Summary

Forty patients with advanced transitional cell cancer (TCC) of the bladder were treated with cisplatin, epirubicin, methotrexate (PEM, every 3–4 weeks). If creatinine clearance was reduced to 40 ml/min, the usual full doses of cisplatin and methotrexate, 50 mg/m², were proportionally reduced. 23 patients had full-dose (FD) therapy, 17 had reduced dose (RD) (40–20 mg/m²). Two patients achieved complete response and 17 partial response. The overall response rate was 19/40 (47.5%), 11/23 (48%) for FD and 8/17 (47%) for RD (p = 1.000). 17/40 pts (42.5%) had no-change and 4/40 (1096) had disease progression. The median duration of CR and PR was 32 weeks, range 4–82 (22 weeks, range 12–52 for FD; 32 weeks, range 4–82 for RD, cisplatin p = .7362). The main side effect was vomiting (35/40 pts, 87.5%, 20/23 = 87% for FD, 15/17 = 90% for RD, p = 1.000). Leukopenia was observed in 12 patients (30%, nadir 3,240, range 900–3,800, 6/23 = 26% for FD, 6/17 = 35% for RD, p=.7285), alopecia in 18 patients (45%, 15/23 = 65% for FD, 3/17 = 18% for RD, p = .004). The results of this study show that a dose escalation to 50 mg/m² for cisplatin, epirubicin and methotrexate in the PEM regimen results in an increase in overall response (OR) (19/40 = 47.5%) with respect to a historical control using the same drugs at doses of 40 mg/m² (12/35 = 34%). In patients with normal renal function the escalated dose was tolerated without a corresponding increase in toxicity. A proportional dose reduction for cisplatin and methotrexate in the PEM regimen in case of reduced renal function did not influence significantly the rate and duration of response.     

Cisplatin-VP16 Alternating with Cyclophosphamide-Epirubicin versus Cyclophosphamide-Epirubicin-Vincristine in Small Cell Lung Cancer

Summary

In the hope of increasing the incidence of objective remissions and the survival time of patients with small cell lung cancer, we conducted a randomized study designed to compare a treatment scheme of alternating chemotherapy featuring cisplatin + etoposide followed by cyclophosphamide t epirubicin versus conventional chemotherapy with cyclophosphamide + epirubicin + vincristine, in a total of 113 patients (56 treated with the alternating regime and 57 treated conventionally). Patients receiving the alternating drug regimen showed some increase in objective remission rates, and above all increased mean survival time (297 days versus 232). The higher incidence of side effects encountered was effectively controlled by the usual medical therapy.     

PUMA基因转染乳腺癌MCF-7细胞增强表柔比星致凋亡敏感性的研究

  目的  探讨PUMA基因转染是否增强乳腺癌MCF-7细胞对表柔比星致凋亡的敏感性。   方法  应用脂质体介导重组真核表达载体PUMA-pCDNA3和空载体pCDNA3质粒瞬时转染至乳腺癌MCF-7细胞中, G418筛选阳性细胞。将系列浓度(0.01~100μmol/L)的表柔比星分别作用于MCF-7、MCF-7/PUMA和MCF-7/pCDNA3细胞72 h, MTT法测定各组细胞的存活率并计算IC50, FCM、TUNEL法检测细胞凋亡情况, Western blotting检测各组细胞PUMA蛋白表达的变化。   结果  MCF-7、MCF-7/PUMA和MCF-7/pCDNA3细胞的表柔比星IC50分别为(13±1.4)、(1.8±0.2)和(10.7±1.3)μmol/L, MCF-7/PUMA细胞对表柔比星作用的敏感性增加了7.2倍。表柔比星以剂量依赖方式诱导MCF-7细胞凋亡, 但对MCF-7/PUMA细胞所诱导的凋亡比MCF-7和MCF-7pCDNA3更明显。低浓度表柔比星(0.1μmol/L)轻微引起MCF-7/pCDNA3[(1.15±0.26)%]和MCF-7细胞凋亡[(0.9±0.24)%], 但能诱导MCF-7/PUMA细胞明显凋亡[(6.44±1.46)%]; 高浓度表柔比星(1μmol/L)诱导各组细胞凋亡, 但表柔比星MCF-7/PU MA细胞凋亡率[(35.47±9.36)%]明显高于MCF-7[(12.6±3.73)%]和MCF-7/pCDNA3细胞[(15.2±5.17)%], 差异均有统计学意义(P < 0.01);FCM和TUNEL方法检测显示相同的结果。PUMA蛋白在MCF-7/PUMA细胞中的表达明显高于MCF-7和MCF-7/pCD NA3细胞。   结论  PUMA基因稳定转染明显地增强了乳腺癌MCF-7细胞增强表柔比星致凋亡作用的敏感性。      

The preliminary evaluation on cholesterol-modified pullulan as a drug nanocarrier

Abstract

To further develop cholesterol-modified pullulan self-aggregated nanoparticles (CHSPNs) as a drug nanocarrier, CHSP was synthesized and characterized. Its cholesterol degree determined by ¹H NMR was 5.2 cholesterol groups per hundred glucose units. CHSPNs were prepared in aqueous media and characterized by dynamic laser light-scattering (DLS), zeta potential and transmission electron microscopy (TEM). These nanoparticles were almost spherical in shape, and the zeta potentials of CHSPNs were near zero in aqueous media. CHSPNs can be stable at least 2 months with no significant size and zeta potential changes. Single dose toxicity test in mice was investigated for the safety evaluation of CHSPNs as a drug nanocarrier, and the result showed CHSPNs were well tolerated at the dose of 200?mg/kg in mice. Epirubicin (EPI)-loaded CHSPNs (EPI-CHSPNs) were prepared and the in vivo pharmacokinetics and biodistribution were studied. Compared with the EPI solution, EPI-CHSPNs have exhibited higher plasma drug concentration, longer half-life time (t_1/2) and the larger area under-the-curve (AUC). Moreover, the drug level of EPI-CHSPNs increased in liver and decreased in heart. The results indicated that CHSPNs were stable, safe and may be a promising drug delivery carrier.     

Low Dose Intermittent 5-Fluorouracil,Epirubicin and Cyclophosphamide (FEC) in Poor Risk Patients with Advanced Transitional Cell Bladder Cancer: a Pilot Study

Summary

Fifteen patients with locally advanced or metastatic bladder carcinoma and with cardiac and/or renal impairment were treated with a combination of 5-fluorouracil, 400 mg/m², epirubicin, 40 mg/m², and cyclophosphamide, 400 mg/m². No complete or partial remissions were observed among the 14 evaluable patients. The toxicity level was very low. We are now trying to «tailor» platinum-based combinations to renal function.     

应变率成像技术评价以表阿霉素为主的化疗方案对乳腺癌患者左心功能影响的研究

目的:探讨应变和应变率成像技术在评价表阿霉素致乳腺癌患者左心功能影响中的优势。方法:选择经病理确诊的女性乳腺癌患者78例。均采用FEC方案化疗。采用自身对照研究对乳腺癌患者6个化疗周期进行观察,分别于化疗前1天及每周期化疗后第5天行心电图、心肌酶学、常规超声心动图及应变率成像检测。SPSS13.0统计软件进行统计分析。结果:随表阿霉素累积量增加,于第4、5周期时心电图异常率增加,第6周期时,心电图异常率明显增加,与化疗前比较,差异有统计学意义(P<0.05);第6周期时出现心肌酶增高(P<0.05);第6周期时左室射血分数(LVEF)及E/A减低(P<0.05);应变率成像结果显示:随表阿霉素累积量的增加,于第4周期时舒张早期峰值应变率(SRe)、房缩期峰值应变率(SRa)减低(P<0.05),第5周期时SRe、SRa明显减低(P<0.01),第6周期时,出现下壁及前壁的SRs减低(P<0.05),后间隔、侧壁、前间隔及后壁的SRs明显减低(P<0.01)。结论:乳腺癌患者化疗过程中,随表阿霉素累计量的增加,心电图和应变率成像较早出现异常,而心肌酶和常规超声心动图指标则较晚出现异常。应变率成像能够早期较精确的反映表阿霉素致乳腺癌患者左心功能的影响。     

含表柔比星联合化疗患者左室收缩功能及同步性实时三维超声心动图的评价

目的:应用实时三维超声技术(RT3DE)评价表柔比星联合化疗患者左心室的收缩功能,观察左室心肌收缩同步性。方法:化疗前及化疗3个周期(63~84 d)后,对表柔比星联合化疗患者(EPI组)及正常人(对照组)进行实时三维超声心动图检查。结果:EPI组左室壁16节段、12节段收缩末期最小容积时间(Tmsv)的标准差和最大差值(即Tmsvl6-SD,Tmsvl6-dif,Tms-vl2-SD,Tmsvl2-Dif)及其心率校正值,均高于对照组,P<0.05;而化疗前与正常对照组相比上述各指标差异无统计学意义,P>0.05。结论:表柔比星联合化疗患者在常规LVEF检查未发现异常的情况下,应用三维成像技术可早期发现左室心肌收缩同步性的异常。     

表柔比星诱导的保护性自噬抑制了胃癌MGC803细胞的凋亡

目的:明确表柔比星作用胃癌MGC803细胞后自噬的存在,探讨自噬在表柔比星诱导胃癌细胞凋亡中的作用。方法:表柔比星处理胃癌MGC803细胞,MTT检测细胞增殖能力,流式细胞术检测细胞凋亡,Western blot检测蛋白表达。结果:1.2μg/ml的表柔比星作用MGC803细胞24h,细胞凋亡率为(23.56±3.49)%,并且多聚ADP-核糖聚合酶(PARP)蛋白发生了裂解。与此同时,1.2μg/ml的表柔比星导致了微管相关蛋白轻链3-Ⅱ(LC3-Ⅱ)蛋白的提高和细胞自噬体的增多。提示表柔比星同时诱导了凋亡和自噬的发生。与单药表柔比星相比,自噬抑制剂氯喹联合表柔比星明显提高了细胞增殖抑制率[(71.79±4.34)%vs(47.70±3.67%),P<0.05]。而且,氯喹联合表柔比星诱导了更明显的MGC803细胞凋亡[(43.98±4.67)%vs(25.09±3.29%),P<0.05]。结论:表柔比星诱导的保护性自噬抑制了胃癌MGC803细胞的凋亡。自噬抑制剂联合表柔比星为胃癌提供了新的治疗策略。