iNOS基因转染对雄激素非依赖性前列腺癌细胞DU145生长的影响

目的:观察诱导型一氧化氮合酶(iNOS)基因转染对雄激素非依赖性前列腺癌细胞DU145生物学行为的影响。方法:将iNOS基因转染到DU145细胞并筛选出阳性细胞进行扩增,并设空载体组和对照组。观察细胞的形态变化,MTT法绘制生长曲线;流式细胞术检测细胞凋亡率;了解NOS抑制剂对转染细胞的影响。结果:转染iNOS后,DU145细胞分泌的NO[(272.50±15.82)μmol/L]显著高于空载体组[(122.00±18.93)μmol/L]和对照组[(121.00±6.98)μmol/L](P<0.05)。流式细胞术检测结果提示转染iNOS组细胞凋亡率[(42.78±2.01)%]明显高于空载体组[(30.65±1.46)%]和对照组[(28.96±1.50)%](P<0.05)。MTT测定结果提示转染组细胞生长较空载体组和对照组减慢(P<0.05),NOS抑制剂可以加快其生长,但无显著性差异(P>0.05)。结论:iNOS基因转染可以使DU145细胞分泌较高浓度的NO,诱导细胞凋亡,抑制细胞生长,为晚期雄激素非依赖性前列腺癌的基因治疗提供一个有效的靶点。     

Chemotherapy in advanced androgen-independent prostate cancer 1990-1999: a decade of progress?

Background and purpose:A great number of clinical researchstudies have been reported in the field of chemotherapy for advancedandrogen-independent prostate cancer during the last ten years. The aims ofthe present review were to assess their impact on management of the diseaseand on survival of patients. Methods:The review of full published reports was facilited by theuse of a MEDLINE computer search. Results:Clinical research studies have focused on definingguidelines for eligibility criteria and accurate endpoints for patients to beenrolled onto clinical trials and developing new agents or combinationof drugs including estramustine phosphate. Any combination of currentchemotherapy has no impact on overall survival of patients. Among drugs indevelopment, only the promising activity observed with docetaxel deservesrandomized trials to assess its impact on survival. The major innovativeadvance of the 90s is the demonstration of the impact of chemotherapy(mitoxantrone + prednisone) on quality of life as compared to prednisonealone. A greater and longer-lasting improvement in quality of life along witha concomitant decrease in costs was observed. Conclusions:At the present time, chemotherapy should beconsidered as a palliative treatment in patients with symptomaticandrogen-independent disease. The enrollment of patients into clinical trialsdealing with quality of life as primary endpoint is strongly solicited. Astandard methodology should be used in phase II trials with a primary goal ofselection of agents which should progress to randomized trials using survivalas an endpoint. Hopefully new specific strategies targeted to reverse themolecular changes that underlie prostate tumorigenesis should rapidly impactthe multimodality management of AIPC in the third millenium.     

NES1/KLK10 and hNIS gene therapy enhanced iodine-131 internal radiation in PC3 proliferation inhibition

NES1 gene is thought to be a tumor-suppressor gene. Our previous study found that overexpression of NES1 gene in PC3 cell line could slow down the tumor proliferation rate, associated with a mild decrease in BCL-2 expression. The BCL-2 decrease could increase the sensitivity of radiotherapy to tumors. Thus, we supposed to have an “enhanced firepower” effect by combining overexpressed NES1 gene therapy and ¹³¹I radiation therapy uptake by overexpressed hNIS protein. We found a weak endogenous expression of hNIS protein in PC3 cells and demonstrated that the low expression of hNIS protein in PC3 cells might be the reason for the low iodine uptake. By overexpressing hNIS in PC3, the radioactive iodine uptake ability was significantly increased. Results of in vitro and in vivo tumor proliferation experiments and ¹⁸F-fluorothymidine (¹⁸F-FLT) micro-positron emission tomography/computed tomography (micro-PET/CT) imaging showed that the combined NES1 gene therapy and ¹³¹I radiation therapy mediated by overexpressed hNIS protein had the best tumor proliferative inhibition effect. Immunohistochemistry showed an obvious decrease of Ki-67 expression and the lowest BCL-2 expression. These data suggest that via inhibition of BCL-2 expression, overexpressed NES1 might enhance the effect of radiation therapy of ¹³¹I uptake in hNIS overexpressed PC3 cells.     

EGF与miRNA-21联合构建雄激素非依赖性前列腺癌LNCaP亚细胞模型

目的构建雄激素非依赖性的人前列腺癌细胞株LNCaP亚型。方法前期常规RPMI 1640培养基培养LNCaP细胞,然后给予无酚红的RPMI 1640培养基,其中加入10%活性碳/葡聚糖处理的胎牛血清,细胞传代后将10μg/L表皮生长因子（EGF）加入培养基,50 nmol/L miRNA-21类似物转染细胞,长期培养。镜下观察细胞形态变化,MTT检测细胞增殖活性,RT-PCR检测雄激素受体基因扩增情况。结果细胞培养约2.5个月后,LNCaP细胞成功转变为非雄激素依赖的前列腺癌细胞LNCaP亚细胞,细胞增殖能力升高,雄激素受体表达上调。结论体内雄激素依赖性前列腺癌可向雄激素非依赖性前列腺癌转变,而且miRNA-21和EGF对该转变起促进作用。     

Development of a prostate-specific promoter for gene therapy against androgen-independent prostate cancer

Androgen ablation has been the standard treatment for metastasized prostate cancer. In most cases, however, prostate cancer cells eventually lose androgen dependency and become refractory to the conventional endocrine therapy. Androgen-independent prostate cancer is characterized by a heterogeneous loss of androgen receptor (AR) expression among tumor cells. Prostate-specific promoters such as prostate-specific antigen and rat probasin (rPB) promoters have been examined in the development of gene therapy targeted to prostate cancer. However, those promoters require binding of the androgen–AR complex to the androgen-response element and are active only in the androgen-dependent prostate cancer cell lines and not in the androgen-independent cell lines. To target transgene expression in androgen-independent prostate cancer, we designed a prostate-specific promoter that is activated by the retinoids–retinoid receptor complex instead of the androgen–AR complex. The modified rPB promoters expressed transgenes in response to retinoid in both androgen-dependent and androgen-independent prostate cancer cells and not in other cancer cell lines or in human normal cells, in vitro and in vivo. Furthermore, the combination of retinoid treatment and adenovirus-mediated gene transfer of the modified rPB-driven HSV-tk gene resulted in a significant growth suppression of the androgen-independent prostate cancer cells in the presence of the prodrug ganciclovir. This study suggests that tailoring of the hormone-responsive elements may offer a new therapeutic opportunity against the hormone-refractory stage of prostate cancer.     

抗人转铁蛋白受体单克隆抗体增强姜黄素对雄激素非依赖性前列腺癌的抑制效应

目的检测抗人转铁蛋白受体单克隆抗体(TfR mAb)对雄激素非依赖性前列腺癌细胞生物学行为的影响,了解抗人TfR mAb对姜黄素抗瘤作用的协同效应。方法利用杂交瘤细胞株制备抗人TfR mAb,分别采用CFSE染色、AnnexinⅤ-PI染色和PI染色法流式细胞仪检测抗人TfR mAb对PC-3细胞增殖、凋亡和细胞周期的影响。采用FITC标记的鼠抗人TfR mAb检测姜黄素对雄激素非依赖性前列腺癌细胞表面TfR表达的影响。采用流式细胞仪进一步检测抗人TfR mAb联合姜黄素对PC-3细胞增殖、凋亡和细胞周期的影响。结果抗人TfR mAb对PC-3细胞增殖、凋亡和细胞周期无明显影响(均P>0.05)。姜黄素能够显著上调雄激素非依赖性前列腺癌细胞表面TfR表达(P<0.05)。抗人TfR mAb可显著增强姜黄素对PC-3细胞凋亡的诱导作用(P<0.05),而不影响姜黄素对PC-3细胞增殖和细胞周期的影响(均P>0.05)。结论姜黄素可导致雄激素非依赖性前列腺癌细胞表面TfR表达增高。抗人TfR mAb单独作用对雄激素非依赖性前列腺癌细胞的生物学行为无显著影响,但抗人TfR mAb可以增强姜黄素对雄激素非依赖性前列腺癌细胞的凋亡效应。     

靶向于雄激素受体的siRNA筛选及效能评价

目的 设计并合成新的靶向于雄激素受体(AR)的siRNA序列,转染前列腺癌细胞筛选最佳干扰序列.方法 设计并合成靶向于雄激素受体的siRNA,以不同浓度转染雄激素非依赖性前列腺癌细胞C4-2,确定最佳转染浓度.以最佳转染浓度转染细胞,分为siRNA Ⅰ组、siRNAⅡ组、siRNAⅢ组、阴性对照组、空白对照组和无关对照...     

An open-label phase II study of low-dose thalidomide in androgen-independent prostate cancer

The antiangiogenic effects of thalidomide have been assessed in clinical trials in patients with various solid and haematological malignancies. Thalidomide blocks the activity of angiogenic agents including bFGF, VEGF and IL-6. We undertook an open-label study using thalidomide 100 mg once daily for up to 6 months in 20 men with androgen-independent prostate cancer. The mean time of study was 109 days (median 107, range 4-184 days). Patients underwent regular measurement of prostate-specific antigen (PSA), urea and electrolytes, serum bFGF and VEGF. Three men (15%) showed a decline in serum PSA of at least 50%, sustained throughout treatment. Of 16 men treated for at least 2 months, six (37.5%) showed a fall in absolute PSA by a median of 48%. Increasing levels of serum bFGF and VEGF were associated with progressive disease; five of six men who demonstrated a fall in PSA also showed a decline in bFGF and VEGF levels, and three of four men with a rising PSA showed an increase in both growth factors. Adverse effects included constipation, morning drowsiness, dizziness and rash, and resulted in withdrawal from the study by three men. Evidence of peripheral sensory neuropathy was found in nine of 13 men before treatment. In the seven men who completed six months on thalidomide, subclinical evidence of peripheral neuropathy was found in four before treatment, but in all seven at repeat testing. The findings indicate that thalidomide may be an option for patients who have failed other forms of therapy, provided close follow-up is maintained for development of peripheral neuropathy.