苯肾上腺素对体外培养人前列腺平滑肌细胞增殖及凋亡的作用

目的探讨苯肾上腺素（PE）对体外培养人前列腺平滑肌细胞增殖及凋亡的作用。方法将原代培养得到的3—5代人前列腺平滑肌细胞随机分组，各组加入浓度为0．1μmol／L～100μmol／L的PE和／或10μmol／L a1受体阻滞剂酚妥拉明（Ph），以噻唑蓝（MTT）检测细胞增殖情况．原位凋亡法（TUNEL）检测细胞凋亡情况。结果PE浓度大于1μmol／L时对前列腺平滑肌细胞有诱导增殖和抗凋亡作用（P均〈0.05），并且存在浓度依赖性。r分别为0．90和-0．893（P均〈0．05）；10μmol／L Ph能够拮抗PE的诱导增殖和抗凋亡作用（P〈0．01）。结论PE可以通过a1受体信号传导途径诱导体外前列腺平滑肌细胞增殖增加和凋亡减少。     

4-羟基他莫昔芬对前列腺基质细胞增殖与凋亡的作用

目的:研究4-羟基他莫昔芬(OHT)对原代培养的前列腺基质细胞增殖与凋亡的影响。方法:以10-8~10-5mol/L的雌二醇(E2)、己烯雌酚(DES)、OHT以及10-8~10-6mol/L的E2与10-7mol/L的OHT混合物分别作用于原代培养的前列腺基质细胞,采用MTT法和TUNEL法分别检测细胞增殖和凋亡。结果:OHT对前列腺基质细胞增殖和凋亡的作用与E2和DES比较均有显著差异(P均<0.05),在10-7~10-5mol/L浓度下表现出与浓度相关(r=-0.383,P=0.005)的抑制增殖作用(P<0.05),10-7mol/L的OHT可以抑制相同甚至更高浓度(10-6mol/L)E2的促增殖作用(P<0.05);OHT在10-8~10-5mol/L浓度下显示与浓度相关(r=0.349,P=0.012)的促凋亡作用(P<0.05),且10-7mol/L OHT的促凋亡作用不能被相同甚至更高浓度(10-6mol/L)E2所逆转(P>0.05)。结论:OHT在一定浓度范围内对原代培养的前列腺基质细胞具有明显的抑制增殖和促凋亡作用,该作用可能不完全是通过竞争性抑制雌激素受体而实现的。     

羟基喜树碱对前列腺癌PC-3细胞凋亡作用的研究

目的:观察羟基喜树碱(HCPT)对前列腺癌PC-3细胞凋亡的影响,初步探讨其作用机制。方法:四甲基偶氮唑盐(MTT)检测不同浓度(1×10-1、1×10-2、1×10-3、1×10-4mg/ml)、不同作用时间(12、24、48h)下HCPT对PC-3细胞增殖的影响;吖啶橙/溴化乙锭(AO/EB)染色观察细胞凋亡情况;琼脂糖凝胶电泳观察凋亡细胞特征性DNA条带;流式细胞术测定HCPT诱导PC-3细胞凋亡率。结果:HCPT明显抑制PC-3细胞生长,呈时间、剂量依赖性,12、24、48h的IC50值分别为:6.50×10-2、2.35×10-2、5.31×10-3mg/ml;荧光显微镜下观察到经AO/EB染色的典型凋亡细胞;琼脂糖凝胶电泳可见凋亡细胞DNA呈规律的梯状条带;流式细胞术显示PC-3细胞凋亡率随HCPT浓度的增加而升高,浓度为1×10-3mg/ml时凋亡率达到最高峰(35.76%)。结论:HCPT可通过诱导凋亡较为明显地抑制PC-3细胞生长,但其作用机制目前尚需进一步研究。     

红三叶总异黄酮对人增生前列腺组织基质细胞增殖和凋亡的影响

目的:评价红三叶总异黄酮对人增生前列腺组织基质细胞增殖和凋亡的影响。方法:采用浓度为12.5、25、50、100μg/ml的红三叶总异黄酮溶液处理前列腺基质细胞,并设立PBS空白对照组,DMSO阴性对照组和浓度为12.5、25.0、50.0、100.0μg/ml的非那雄胺溶液为阳性对照组。MTT法测定红三叶总异黄酮对细胞增殖的影响;AnnexinVFITC/PI双染色法流式细胞术分析红三叶总异黄酮对细胞凋亡的作用。结果:当红三叶总异黄酮浓度达到25.0μg/ml时,其对人前列腺增生组织基质细胞的增殖抑制率为18.86%,与空白对照组(5.17%)相比差异有显著性(P<0.05);且随着药物浓度的增加,抑制作用也愈趋明显。与非那雄胺阳性对照组相比,当浓度达到50.0μg/ml时,红三叶总异黄酮实验组对人前列腺增生组织基质细胞的抑制增殖作用弱于非那雄胺阳性对照组(28.00%vs69.88%),差异有显著性(P<0.05)。流式细胞术分析结果表明,与阴性对照组、空白对照组相比,红三叶总异黄酮浓度达到25.0μg/ml时能够诱导前列腺基质细胞的凋亡,凋亡率为(18.54±2.50)%(P<0.01)。结论:红三叶总异黄酮对前列腺基质细胞有较明显的抑制生长,促进凋亡作用。     

转化生长因子—β1对前列腺基质细胞基因表达的调节作用

目的探讨转化生长因子-β1(TGF-β1)对前列腺基质细胞基因表达的调节作用.方法原代培养人前列腺基质细胞,并传代至4～6代.分别将浓度为0.01、0.10、1.00、10.00μg/L的TGF-β1加入细胞培养液中.孵育48h后收集细胞.用内参照半定量RT-PCR方法检测前列腺基质细胞雄激素受体(AR)、TGF-β1、bFGF和平滑肌特异性标记蛋白smoothelin基因的转录水平.结果与对照组相比,低浓度(0.01μg/L)的TGF-β1可增强体外培养的前列腺基质细胞内AR表达(P<0.01),差别有显著性意义.随TGF-β1浓度增加,促AR表达作用减弱.随TGF-β1浓度增加基质细胞TGF-β1、bFGF和smoothelin基因的转录增加(P<0.01),并且随着应用浓度增加促各基因转录的作用增强.结论TGF-β1对前列腺基质细胞基因表达具有广泛的调节作用,在前列腺增生发病中具有重要作用.     

TGFβ1，bFGF对前列腺基质细胞增殖和分化的影响

目的　探讨前列腺基质增生的机制。　方法　系用ＭＴＴ和ＴＵＮＥＬ法检测体外原代无血清培养的前列腺基质细胞的增殖,用免疫组化、ＲＴＰＣＲ 方法检测平滑肌细胞特异性标记蛋白的表达。　结果　ＴＧＦβ有多重效应：浓度为０－０１ ～１０．００ｎｇ／ｍｌ 的ＴＧＦβ可抑制指数增生期前列腺基质细胞增殖;浓度低于０－１ｎｇ／ｍｌ 的ＴＧＦβ刺激平顶期前列腺基质细胞增殖;浓度高于１ｎｇ／ｍｌ 的ＴＧＦβ促增殖平顶期的成纤维细胞向平滑肌细胞分化。ｂＦＧＦ对于指数增生期和平顶期细胞均有刺激增殖的作用,并抑制增殖平顶期的成纤维细胞向平滑肌细胞分化。　结论　ＴＧＦβ１／ｂＦＧＦ比例的改变有调节前列腺基质细胞的稳态平衡的作用。     

丝裂霉素诱导人肝癌细胞凋亡的研究

本研究旨在观察在体外丝裂霉素(ＭＭＣ)对人肝癌细胞凋亡的诱导作用 ,从凋亡的角度探讨其抗癌机理 ,现将结果报道如下。一、材料与方法1.细胞培养及实验分组 :人肝癌ＢＥＬ 740 2细胞株来自中国科学院上海细胞所 ,用含高糖的ＤＭＥＭ培养液 ,补充体积分数为 12 %的胎牛血清、青霉素 (10 4 Ｕ/Ｌ)、键霉素 (10 0 μｇ/Ｌ) ,于37℃ ,体积分数为 5 %的ＣＯ2 孵箱中培养。实验分药物处理组与对照组 ,处理组又分 2× 10 -2 、2× 10 -3 、2× 10 -4 ｇ/ＬＭＭＣ 3种浓度 ,作用时间为 2 4ｈ。2 .透射电镜 :将浓度为 2× 10 -2ｇ/Ｌ的ＭＭＣ处理Ｂ…     

前列腺素E1抗大鼠骨髓间充质干细胞凋亡的最佳浓度探讨

目的探讨在体外条件下前列腺素E1抗大鼠骨髓间充质干细胞(BMSCs)凋亡的最佳浓度。方法提取SD大鼠骨髓间充质干细胞,取P3-P5代的大鼠骨髓间充质干细胞在体外缺血清缺氧条件下进行培养,将前列腺素E1分别以0μg/L(对照组)、1μg/L、10μg/L、20μg/L、30μg/L、40μg/L、50μg/L、100μg/L的浓度作用于大鼠骨髓间充质干细胞,并设置48 h,72 h二个时间点,用流式细胞检测的方法测定每个时间点及每个浓度组的大鼠骨髓间充质干细胞凋亡率,最后对数据进行统计分析。结果在各个时间点中,质量浓度为1μg/L、10μg/L、20μg/L、30μg/L、40μg/L、50μg/L、100μg/L的前列腺素E1均可减少大鼠骨髓间充质干细胞的凋亡,其中20μg/L浓度组的大鼠骨髓间充质干细胞凋亡率最低;前列腺素E1在作用48 h后,大鼠骨髓间充质干细胞凋亡率最低。结论体外缺血清缺氧条件下,前列腺素E1抗大鼠骨髓间充质干细胞凋亡的最佳浓度是20μg/L,且其抗凋亡作用在48 h时达到高峰。     

槐耳清膏诱导人直肠癌HR8348细胞凋亡的实验研究

目的　探讨槐耳清膏在体外对人直肠癌HR83 48细胞的生长抑制作用和凋亡诱导作用及其作用机理。方法　将处于对数生长期的HR83 48细胞用含槐耳清膏的培养基培养 3 6h ,用四氮唑蓝 (MTT )比色法检测吸光度 (OD)值 ,计算抑制率 ;用甲基绿 派若宁染色法及TUNEL法检测细胞凋亡指数 ;用免疫组织化学方法检测bcl 2、bcl xl、bax、bak及 p5 3基因表达的情况。 结果　槐耳清膏对HR83 48细胞的抑制率随浓度增加而上升 ,浓度为 4.0mg/ml时抑制率最大 (71.1% ) ,与 5 FU组 (浓度为 10 μg/ml)相比差异无显著性意义 (P>0 .0 5 )。甲基绿 派若宁染色法和TUNEL法均可见到典型的细胞凋亡、凋亡小体或出泡现象 ,凋亡指数随槐耳清膏浓度的增加而增加 ,当浓度达 4.0mg/ml时 ,凋亡指数迅速上升 ,甲基绿 派若宁法为 0 .162 0± 0 .0 12 8,TUNEL法为 0 .2 612± 0 .0 15 8,均大于 5 FU组的凋亡指数(0 .0 780± 0 .0 0 95和 0 .10 2 8± 0 .0 13 1) ,P<0 .0 5。槐耳清膏组bcl 2、bcl xl、bak、p5 3蛋白表达较空白对照组明显增强(P<0 .0 5 ) ,而bax变化不明显 (P>0 .0 5 )。槐耳清膏组bak/bcl 2和bak/bcl xl比值显著大于空白对照组。结论　槐耳清膏在体外对人直肠癌HR83 48细胞具有显著的抑制作用和凋亡诱导作用。槐耳清膏     

氯胺酮对体外培养大鼠神经干细胞增殖与凋亡的影响

目的探讨氯胺酮对体外培养夫鼠神经干细胞(NSC)增殖与凋亡的影响。方法采用无血清培养和单细胞克隆技术,在大鼠海马分离培养具有单细胞克隆能力的细胞群,采用免疫荧光细胞化学技术证实为NSC。将NSC以5×10~4/孔接种于96孔培养板中,分别加入浓度为0(未加氯胺酮)、5、10、20、50、100、200、500、1000 mmol·L~(-1)氯胺酮,每个浓度5孔。采用四甲基偶氮唑蓝比色法检测NSC光密度(OD),并计算生长抑制率(RI)。采用流式细胞仪测定氯胺酮浓度为0、10、100、500、1000 mmol·L~(-1)时NSC凋亡率。结果与氯胺酮浓度0时比较,200、500、1000 mmol/L氯胺酮可降低NSC OD,升高RI,10、100、500、1000 mmol·L~(-1)氯胺酮可升高NSC凋亡率(P＜0．05或0．01)。结论氯胺酮对体外培养大鼠NSC增殖有抑制作用,并能诱导NSC凋亡,且该作用与氯胺酮浓度有关     

Alpha 1-adrenoceptor antagonists terazosin and doxazosin induce prostate apoptosis without affecting cell proliferation in patients with benign prostatic hyperplasia.

PURPOSE: Recent evidence indicated that an alpha 1 blocker, doxazosin, induces prostate apoptosis in patients with benign prostatic hyperplasia (BPH). In this study, to determine whether this apoptotic response was mediated by alpha 1 adrenoceptor-dependent mechanism or was specific to doxazosin, we examined the effect of another alpha 1 blocker, terazosin, in addition to doxazosin, on the dynamics of prostate cell growth. MATERIALS AND METHODS: Cell proliferation and apoptosis were evaluated in BPH patients, an untreated (control) group (n = 31), and men treated with terazosin (n = 42) and doxazosin (n = 61) for the relief of the obstructive symptoms. Terazosin (1 to 10 mg./day) and doxazosin (2 to 8 mg./day) treatment varied from 1 week to 3 years. Ki-67 immunostaining and the TUNEL assay were used to evaluate the proliferative and apoptotic indices, respectively, in both the epithelial and stromal components of prostate (biopsy and prostatectomy) specimens. The smooth muscle cell content of the prostatic stroma was identified on the basis of smooth muscle alpha-actin immunoreactivity. RESULTS: A significant induction of apoptosis was observed in both the prostatic epithelial and stromal cells within the first month of terazosin and doxazosin therapy, as compared with untreated controls (p < 0.05). Furthermore, the marked induction of prostatic stroma apoptosis in response to both alpha 1 adrenoceptor antagonists was paralleled by a significant decrease in the smooth muscle alpha-actin expression. This loss of prostatic smooth muscle cells correlated with morphological stromal regression (as detected by trichrome staining) and BPH symptom improvement. Neither terazosin nor doxazosin therapy resulted in significant changes in prostate cell proliferation. CONCLUSIONS: These findings demonstrate that alpha-blockers as a class may regulate prostate growth by inducing apoptosis in both the epithelial and stromal cells, with little effect on cell proliferation. Apoptosis-mediated prostate stromal regression appears as a molecular mechanism underlying the therapeutic response to alpha 1 blockade in the treatment of BPH.     

Dual effects of ouabain on the regulation of proliferation and apoptosis in human prostatic smooth muscle cells.

PURPOSE: To elucidate the role of ouabain in the pathophysiology of benign prostatic hyperplasia we examined the effects of ouabain on the proliferation and apoptosis of human prostatic smooth muscle cells. MATERIALS AND METHODS: Primary cultures of human prostatic smooth muscle cells were obtained from 7 patients with bladder outlet obstruction caused by benign prostatic enlargement. A cell proliferation study was performed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay method to examine the effects of different concentrations of ouabain and various inhibitors. Western blot analysis was done to determine mitogen activated protein kinase (MAPK) activation. The terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labeling reaction method and caspase-3 activity assay were also performed to examine the apoptotic mechanism. RESULTS: Ouabain exhibited a modest but significant proliferative effect in nanomolar concentrations; whereas it induced cell apoptosis at higher concentrations. Ouabain caused rapid activation of p42/44 MAPKs. The proliferative effect of ouabain was completely flattened by W-7 and MAPK kinase (MEK) inhibitor, suggesting the requirement of Ca(2+) mobilization and the involvement of the MEK-p42/44 MAPK cascade. The cytotoxic effect by ouabain was defined as apoptosis and necrosis using the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labeling reaction technique and lactate dehydrogenase release assay, respectively. In addition, ouabain induced profound caspase-3 activity in the cytotoxic concentrations and DEVD-CHO reversed the cytotoxic action to ouabain, demonstrating the involvement of caspase-3 activation in the cytotoxic action. CONCLUSIONS: Ouabain at different concentrations caused dual effects on proliferation and apoptosis in human prostatic smooth muscle cells. At low concentrations ouabain promoted cell proliferation via a Ca(2+) dependent mechanism and activation of the MEK-p42/44 MAPK pathway; whereas it induced cell apoptosis via the activation of caspase-3 activity at higher concentrations.     

INDUCTION OF PROSTATE APOPTOSIS BY DOXAZOSIN IN BENIGN PROSTATIC HYPERPLASIA

Purpose

The molecular mechanisms underlying the therapeutic effect of the alpha 1 blocker, doxazosin, on benign prostatic hyperplasia (BPH) are poorly understood. We evaluated the effect of doxazosin on cell proliferation and apoptosis in the prostatic glandular epithelium and stroma of patients with BPH.

Materials and Methods

We examined proliferative and apoptotic activities in prostate specimens of 22 men a mean of 65 years old with BPH before and after doxazosin treatment within the normal therapeutic range. Proliferative and apoptotic indexes were determined using Ki-67 nuclear antigen staining and the terminal transferase end labeling assay, respectively. The smooth muscle cell content in prostatic specimens was identified by smooth muscle alpha-actin, and desmin immunoreactivity and apoptotic indexes were correlated with prostatic stromal tissue regression and improvement in BPH symptoms.

Results

In response to doxazosin treatment there were no significant changes in the kinetics of cell proliferation in the prostatic epithelial or stromal cell population. Mean pretreatment baseline apoptosis was 1.9 and 1.0% for the epithelial and stromal prostate components, respectively. Mean apoptotic indexes significantly increased after 3 months of doxazosin treatment in the glandular epithelial (6%) and smooth muscle cells (15%). By 12 months after treatment epithelial apoptosis had decreased to constitutive levels, while the apoptotic index of prostatic stroma cells remained high. Doxazosin induced smooth muscle cell apoptosis correlated with prostatic stromal degeneration, decreased alpha-smooth muscle actin expression and improved BPH symptoms.

Conclusions

These findings implicate the induction of prostate apoptosis by doxazosin as a potential molecular mechanism underlying the acute and chronic therapeutic responses of BPH to alpha 1 blockade.     

Influence of the alpha1-adrenergic antagonist, doxazosin, on noradrenaline-induced modulation of cytoskeletal proteins in cultured hyperplastic prostatic stromal cells

BACKGROUND: Doxazosin, an alpha1-adrenergic antagonist, inhibits sympathetic contraction of prostatic stromal smooth muscle cells and is used in the relief of obstructive benign prostatic hyperplasia (BPH). In vitro application of noradrenaline stimulates expression of cytoskeletal filaments, particularly actin and myosin, by prostatic stromal cells, thus enhancing their differentiation towards smooth muscle cells. This study examined the possible role of doxazosin in reversing this phenotypic modulation as well as in inhibiting smooth muscle cell contraction. METHODS: Stromal cell tissue cultures derived from 10 human hyperplastic prostates were rendered quiescent by reduction of stripped fetal calf serum (FCS) to 1% (v/v) in the medium followed by treatment with 20 microM noradrenaline and/or 1 microM doxazosin for 10 days. Doxazosin, in 10-fold increments of concentration, was also added, separately, to two of these cell cultures, which were either quiescent or growing in 10% normal (unstripped) FCS. Harvested cells were labelled with fluorescein-labelled antisera to smooth muscle cytoskeletal filaments, and their individual fluorescence levels were analyzed flow-cytometrically. RESULTS: Noradrenaline increased expression of all cytoskeletal filaments studied. This effect was greatest for actin and myosin in proliferating cell cultures. Doxazosin largely reversed the increase in filament expression. This effect was most significant for actin and myosin and greatest in quiescent cultures. However, inhibition of the agonist effect of noradrenaline by doxazosin showed no clear dose-related response, in that expression of cytoskeletal filaments was differentially inhibited. CONCLUSIONS: The data suggest that doxazosin may inhibit not only stromal contraction of differentiated smooth muscle cells in BPH but also the phenotypic modulation of stromal smooth muscle cell differentiation induced by noradrenaline. These actions, together, may render prostatic stroma less contractile, and hence less able to respond to sympathetic stimulation, in patients with BPH. While effects on isolated stromal cells are of undoubted importance, failure to demonstrate a consistent dose-response relationship between expression of smooth muscle cell phenotype and inhibition by doxazosin suggests that additional influences, including humoral factors as well as the proximity of differentiated epithelium, are also likely to be involved in this interaction in the intact tissue.     

Androgen and prostatic stroma

Aim: To investigate the effect of androgen on the proliferation, differentiation and regression of canine prostatic stromal cells in vivo and human stromal cells in vitro. Methods: Twenty-two dogs, including 15 normal prostate dogs and 7 prostatic hyperplasia dogs, had their serum concentration of testosterone and estrodiol determined by radioimmunoassay before and after castration. The expression of androgen receptor (AR) and estrogen receptor (ER) in the prostate were analysed by immunohistochemistry and semi-quantitative RT-PCR before and after castration. Light microscopy, transmission electron microscopy and TUNEL assay were carried out successively before and after castration to evaluate the prostatic histomorphology. In vitro serum-free cell cultures from human prostatic stroma were established and exposed to dihydrotestosterone (DHT). The proliferation of the cell culture was detected by MTT assay. The expression of TGFβ, bFGF, AR, and smooth muscle cell (SMC) specific proteins (myosin and/or sm     

特异性阻断Shh信号通路对胰腺癌细胞系SUIT-2增殖和凋亡的影响

目的： 研究组抑胚胎发育相关信号通路Sonic hedgehog (Shh)对人胰腺癌细胞系SUIT-2增殖和凋亡的影响。方法：用四唑蓝（MTT）比色试验检测Shh信号通路特异性抑制剂cyclopamine对胰腺癌细胞系SUIT-2增殖的抑制作用；流式细胞术检测细胞增殖指数(PI)和凋亡指数(AI)；用裸鼠移植瘤模型检测cyclopamine对移植瘤生长的抑制作用。 结果：cyclopamine对SUIT-2细胞株增殖的抑制作用呈剂量和时间依赖性。cyclopamine作用后使胰腺癌细胞周期阻滞在G0／G1期，细胞凋亡增加；SUIT-2的AI为14.3±0.35， PI为36.1±0.44，对照组分别为1.3±0.24和52.3±0.28（均P<0.05）。在裸鼠移植瘤模型中，cyclopamine同时给药组肿瘤生长明显受到抑制，而延期给药组对肿瘤生长的抑制作用较弱。结论：shh信号分子对胰腺癌细胞的增殖起维持作用；通过特异性阻断该信号通路，可以抑制胰腺癌细胞增殖，并促进细胞凋亡。     

Morphological and Pharmacological Characterization of Guinea-Pig Prostatic Smooth Muscle Cells in Vitro

Background Prostatic smooth muscle is thought to play a major role in the pathogenesis of bladder outlet obstruction in patients with benign prostatic hypertrophy. However, the physiology of prostatic smooth muscle cells remains largely unknown, in part due to the lack of a suitable model system. We therefore sought to establish an in vitro culture of guinea pig prostatic smooth muscle cells. Methods: Immature guinea pig prostate was treated by enzymatic digestion and the cells obtained were used to initiate the primary culture. After 3 to 4 passages, cultured smooth muscle cells were examined morphologically by immunocytochemistry and electron microscopy. The contractile properties of cultured smooth muscle cells were also examined.
Results The cultured prostatic cells demonstrated hill and valley morphology, which is a hallmark of smooth muscle cells in vitro, and stained positively for desmin. In addition, electron microscopic examination of ultrastructural morphology revealed myofilaments. Confluent cultures of prostatic smooth muscle cells showed a clear, dose-dependent contractile response to phenylephrine. Furthermore, contraction of the prostatic smooth muscle cells by 10_-6 mol/L phenylephrine was completely inhibited by pretreatment with 10_-6 mol/L terazosin.
Conclusions An in vitro culture of prostatic smooth muscle cells was established. This culture is likely to provide a powerful tool for elucidating the physiology and pathophysiology of prostatic smooth muscle.     

Combined effect of terazosin and finasteride on apoptosis, cell proliferation, and transforming growth factor-beta expression in benign prostatic hyperplasia

BACKGROUND: Medical treatment of benign prostatic hyperplasia (BPH) targets relief of symptoms by causing either relaxation of the prostatic smooth muscle with alpha1 adrenergic blockade, or shrinkage of the gland with 5alpha-reductase inhibitors. We recently demonstrated that alpha1-blockers, such as terazosin, induce apoptosis in prostatic cells. In this study, we examined the combined effect of finasteride and terazosin on the rate of apoptosis and cellular proliferation to investigate their potential synergy at the cellular level. METHODS: Prostate specimens were obtained from men who were treated with either finasteride (n = 24), terazosin (n = 42), or combination therapy (n = 10) for varying time periods (1 week to 36 months) for the relief of the symptoms of BPH. The proliferative and apoptotic indices of both stromal and epithelial prostatic cell populations were determined. Antibodies against TGF-beta1 and TbetaRII were used to examine the immunoreactivity of TGF-beta1 and TbetaRII, respectively, in all prostate tissue sections. RESULTS: The apoptotic index in both prostate cell populations was significantly higher following the combination treatment compared to terazosin or finasteride alone. There were no significant changes in the rate of cellular proliferation with any treatment. Furthermore, there was a significant increase in TGF-beta1 expression in the prostates of patients treated with terazosin or combination therapy, while there was no change in TbetaRII expression. CONCLUSIONS: These results support the concept that induction of prostate apoptosis is a potential molecular mechanism underlying the combination effect of alpha1 blockade with 5alpha-reductase inhibitors in the effective treatment of BPH. The upregulation of TGF-beta1 implies a role for this ligand as an effector of apoptosis induction in response to alpha1-blockade or finasteride therapy of BPH patients.     

Antiproliferative effect of heparin on human smooth muscle cells cultured from intimal hyperplastic lesions of vein grafts

The antiproliferative effect of heparin on cultured smooth muscle cells in proliferating human smooth muscle cells derived from clinical lesions of intimal hyperplasia was tested. Smooth muscle cells were obtained from stenotic segments excised from failing in situ saphenous vein bypass grafts in three patients. The nonadventitial portion of the excised tissue was explanted into cell culture using standard techniques without the addition of exogenous growth factors. Under these conditions, rapid cell outgrowth was observed from these explants, in contrast to minimal growth of smooth muscle cells from normal veins from the same patients. Immunohistochemical staining with antiactin antibody confirmed that the cells cultured from the stenotic lesions were smooth muscle cells. Incubation of these cells with porcine mucosal heparin revealed a significant (p<.01) dose-dependent inhibition of cell proliferation as measured by radioactive thymidine incorporation. Mean inhibition of six subcultures tested ranged from 3 to 46%, at heparin concentrations of 1 to 1,000µg/ml. The magnitude of heparin's antiproliferative effect varied among the cell lines from different patients, but 10–30% inhibition was consistently observed at heparin concentrations usually attained in vivo. The maximal inhibition achieved was 65% in one cell line at the highest heparin dose. We conclude that heparin exerts a significant antiproliferative effect on human smooth muscle cells cultured from intimal hyperplastic lesions from in situ saphenous vein bypass grafts.Presented at the 5th Annual Meeting of the Eastern Vascular Society, May 4, 1991, Pittsburgh, Pennsylvania.