Reconsideration of the clinical and histopathological significance of angiogenesis in prostate cancer: Usefulness and limitations of microvessel density measurement

Angiogenesis plays important roles in tumor growth and cancer cell dissemination in almost all cancers. In prostate cancer, there is general agreement that increased angiogenesis is an important factor in determining tumor development and prognosis in these patients. Microvessel density is recognized as a useful marker for evaluating the angiogenic status of cancer tissues. Many investigators have reported that microvessel density is significantly associated with pathological features and outcomes in prostate cancer patients; however, some researchers have expressed opposing opinions. As the reason for such discrepancy, previous reports have suggested differences in the methodologies of measuring microvessel density in cancer tissues. In the present review, we focus on the variation in such methods, including the selected area and the method used for (semi)quantification. In particular, we discuss the relationship between malignancy potential, tumor progression, and survival and differences in the antibodies used for detection of endothelial cells in detail. We briefly compare the pathological significance and prognostic roles of microvessel density measured using von Willebrand factor, CD31, CD34, and CD105. Based on these analyses, the advantages and limitations of microvessel density measurements in prostate cancer tissues are clarified. Improved “real” and “specific” markers of cancer‐related angiogenesis are necessary for better predictions of prognoses and for discussion of treatment strategies for patients with prostate cancer. However, establishment of a satisfactory cancer‐related endothelial marker could take a long time. Therefore, knowledge regarding the pathological significance of microvessel density – based on understanding of the advantages and limitations of microvessel density determination methods – is important.     

前列腺癌PTEN蛋白表达和微血管密度的相关性研究

目的　研究前列腺癌组织中PTEN蛋白的表达和微血管密度(MVD)的相关性及其意义。方法　应用免疫组化SP法检测3 2例前列腺癌及5例良性前列腺增生组织中PTEN蛋白表达及微血管计数,分析其意义和相关性。结果　3 2例前列腺癌中8例PTEN蛋白表达阳性(2 5 % ,8/3 2 ) ,并随病理分级升高阳性表达率下降,高分化组同中分化组间差异无显著性(P >0 .0 5 ) ,但高分化、中分化组同低分化组之间差异有显著性(P <0 .0 5 ) ,且在浸润型肿瘤(C D)期与局限性肿瘤(A B)期的差异有显著性(P <0 .0 1)。前列腺癌组织中MVD(5 2 .86±17.87) ,MVD随病理分级和临床分期的升高而升高,并同PTEN蛋白的表达成负相关(r =-0 .65 3 ,P <0 .0 1)。结论　PTEN蛋白低表达和微血管的形成在前列腺癌的发生、发展中起重要作用。检测PTEN蛋白的表达和MVD有助于判断病情及预后。PTEN蛋白的低表达与肿瘤微血管的形成相关。     

晚期前列腺癌内分泌治疗后血清PSA、f-PSA含量的变化

目的探讨前列腺癌(PCa)患内分泌治疗后前列腺特异抗原(PSA)、游离前列腺特异抗原与总前列腺特异抗原比值(f／tPSA)变化的临床意义。方珐测定PCa患内分泌治疗前及治疗后1、3、6个月血清PSA、游离前列腺特异抗原(f-PSA)变化。砖杲治疗后1个月与治疗前相比血清PSA下降明显，治疗后6个月较治疗后1个月血清PSA下降亦有显意义；治疗后患血清f-PSA水平明显下降。f／tPSA值的变化无显意义。结论血清PSA、f-PSA可作为判断PCa内分泌治疗效果的标准．如血清PSA、f-PSA复又升高提示肿瘤复发。     

ADAMTS1, a putative anti‐angiogenic factor,is decreased in human prostate cancer

OBJECTIVE

To investigate the expression of ‘ADAM metallopeptidase with thrombospondin type I motif, 1’ (ADAMTS1) in human prostate cancer, and to study its relationship to microvessel density (MVD) and metastasis. ADAMTS1 has been described as an anti‐angiogenic and antitumour factor, but its function in prostate cancer is unknown.

PATIENTS AND METHODS

ADAMTS1 expression was evaluated by immunohistochemistry in specimens obtained by transurethral resection of the prostate from patients with hormone‐naïve and hormone‐refractory prostate tumours, including adjacent benign tissue. A semiquantitative scoring system was used for evaluating the staining. MVD was quantified by counting the number of CD34‐positive blood vessels.

RESULTS

ADAMTS1 was strongly expressed in the luminal epithelial cells in benign prostate glands, whereas expression was significantly lower in prostate cancer cells. There was no obvious difference between hormone‐naïve and hormone‐refractory tumours, and ADAMTS1 expression did not correlate with Gleason score. However, in hormone‐refractory tumours from patients with metastatic disease, the expression of ADAMTS1 was significantly lower than in tumours from patients without metastases. Furthermore, the MVD was higher in hormone‐refractory than in hormone‐naïve tumours and benign tissue, and MVD correlated with Gleason score. There was no association between ADAMTS1 and MVD in the hormone‐naïve tumours, while hormone‐refractory tumours with low ADAMTS1 expression had a higher MVD than those with moderate/high expression.

CONCLUSION

ADAMTS1 expression is decreased in prostate cancer, and might be involved in the early steps of prostate cancer development. Further, ADAMTS1 might have an anti‐angiogenic and antimetastatic role in hormone‐refractory prostate cancer, where low ADAMTS1 expression is associated with a high MVD and metastasis.     

Efficacy of primary hormonal therapy for patients with localized and locally advanced prostate cancer: A retrospective multicenter study

AIM: A retrospective review of patients with localized and locally advanced prostate cancer was performed to evaluate the efficacy of primary hormonal therapy and predict long-term prognosis in these patients. METHODS: A total of 628 patients who were diagnosed with stage T1c to T3 prostate cancer were treated with primary hormonal therapy at participating institutions. The patients were classified based on pretreatment prostate-specific antigen (PSA) level, Gleason score, and time to nadir PSA level. Disease-specific and progression-free survival rates were investigated, and compared among the subgroups. RESULTS: The mean age of patients was 74.5 years, and median pretreatment PSA level was 14.0 ng/mL. A total of 399 patients (63.5%) were treated with combined androgen blockade (CAB), and 229 patients (36.5%) were treated with castration monotherapy. The disease-specific survival rate of all 628 patients was 89.1% at 8 years. The group that showed a good response to primary hormonal therapy (Group G, pretreatment PSA level < or =20 ng/mL, Gleason score < or =7, and time to nadir PSA < or =6 months) accounted for approximately one-third of the total number of T1c-T3 patients. Disease-specific and progression-free survival rates at 8 years in Group G were 98.9% and 82.0%, respectively. These rates increased to 100% and 87.3%, respectively, in patients receiving CAB treatment in Group G. CONCLUSIONS: The results indicate the usefulness of primary hormonal therapy, especially CAB treatment, for patients showing a good response to hormonal therapy in long-term control of localized and locally advanced prostate cancer.     

Differential expression of angiopoietin-2 and vascular endothelial growth factor in androgen-independent prostate cancer models

OBJECTIVE

To investigate the relationship between microvessel density (MVD), blood vessel morphology and the expression of angiopoietin (Ang)‐1, Ang‐2, tyrosine kinase with immunoglobulin and epidermal growth factor homology domains (Tie)‐2, and vascular endothelial growth factor (VEGF) in androgen‐dependent (AD) and androgen‐independent (AI) prostate cancer models, to gain insight into the regulation of angiogenesis at different stages of prostate cancer.

MATERIALS AND METHODS

MVD and blood vessel morphology were evaluated by CD34 immunohistochemical staining. The mRNA and protein secretion of the Angs, Tie‐2 and VEGF were measured by real‐time polymerase chain reaction and enzyme‐linked immunosorbent assays, respectively, in LNCaP (AD) and LNCaP‐19, C4‐2, C4–2B₄ and PC‐3 (AI) prostate cancer xenografts in mice.

RESULTS

LNCaP, C4‐2 and C4–2B₄ xenografts had high expression of Ang‐2 and VEGF, similar MVD and blood vessel morphology_. However, the most angiogenic cell line LNCaP‐19 expressed low levels of both factors and had different vessel morphology. PC‐3 xenografts had a similar MVD to LNCaP, C4‐2 and C4–2B₄, but the Ang‐2 and VEGF expression as well as the vessel morphology were similar to LNCaP‐19.

CONCLUSION

The differences in MVD, blood vessel morphology and the expression of Ang‐2 and VEGF show that prostate cancer cells display angiogenic heterogeneity, which indicates different roles of these factors in the regulation of angiogenesis in different stages of prostate cancer.     

Susceptibility of the prostate cancer cell to different physical, hormonal, and chemical agents: present status and theoretical prospects for improved prostate cancer therapy

The benefits and limitations of present modes of treatment of prostatic cancer with physical, hormonal, and chemical agents are briefly reviewed. The theoretical possibility that the heterogeneous clones that comprise prostatic cancer might be killed or controlled by selective targeting of cytotoxic agents (actual or potential) to malignant cells is discussed in terms of two types of delivery vehicles to provide for cell selectivity: (1) monoclonal antibodies against specific cell surface markers on cancer cells and (2) steroid ligands for receptors present in clones of malignant cells. The problems and prospects of these selective delivery systems as potential therapeutic modalities for prostatic cancer are considered.     

氩氦刀冷冻术联合间歇性内分泌治疗治疗局部晚期前列腺癌的初步研究

目的探讨氩氦刀冷冻术(argon-helium cryoablation,AHC)联合间歇性内分泌治疗(intermittent hormonal therapy,IHT)治疗局部晚期前列腺癌(locally advanced prostate cancer,LAPC)的疗效和安全性。方法回顾性分析经直肠超声引导下经会阴前列腺穿刺AHC联合IHT治疗的21例LAPC患者的临床资料,并与18例单纯行IHT治疗的LAPC患者进行对照。评估的指标包括血清总前列腺特异性抗原(total prostate specific antigen,tPSA)、最大尿流率(Qmax)、国际前列腺症状评分(IPSS)、前列腺体积、前列腺MRI和全身骨扫描,生活质量调查采用欧洲癌症研究与治疗组织的QLQ-C30总量表和QLQ-PR25子量表,并记录不良反应。结果 AHC治疗患者的tPSA提前达到最低值,Qmax和IPSS评分改善明显,前列腺体积明显缩小,第一轮停用内分泌药物的时间也明显延长;躯体功能和性功能的明显下降以及局部的疼痛,对患者的生活质量造成一定的影响。AHC术后主要并发症为阴囊水肿、盆腔疼痛、闭孔神经炎、尿道腐肉和后尿道狭窄,但未出现尿失禁、尿道直肠瘘等严重并发症。结论 AHC联合IHT治疗LAPC是一种可选择的安全、有效的方法。     

非那雄胺对大鼠前列腺eNOS表达和微血管的影响

目的　评价非那雄胺对大鼠前列腺微血管的影响并探讨其机制。方法　①将雄性SD大鼠随机分为三组 ,每组 10只 ,按4 0mg/(kg·d)喂饲非那雄胺 7d(B组 )、14d(C组 ) ,以喂饲生理盐水为对照组 (A组 )。②HE染色观察采用墨汁灌注染色的大鼠前列腺微血管的改变。③免疫组织化学SP法检测大鼠前列腺组织中内皮型一氧化氮合酶 (eNOS)的蛋白表达。结果　①B、C组的微血管密度较A组分别下降了 35 .2 %、5 6 %。②eNOS的蛋白表达较A组分别减少 15 .7%、5 2 .5 %。结论　非那雄胺可抑制大鼠前列腺组织中eNOS的蛋白表达进而抑制前列腺的微血管生成。     

胆囊癌组织EMMPRIN,TIMP-2,MMP-1的表达及其与微血管密度的关系

目的研究胆囊癌组织中EMMPRIN,TIMP-2和MMP-1的表达及其与微血管密度(microvessel den-sity,MVD)的关系,探讨它们之间及其与胆囊癌临床病理特征的相互关系。方法用ABC免疫组化法测定31例胆囊癌组织及10例慢性胆囊炎组织中EMMPRIN,TIMP-2,MMP-1的表达水平及MVD。结果31例胆囊癌组织中EMMPRIN,MMP-1的阳性表达率(61.3%,51.6%)及其评分均值(2.13±1.33,2.03±1.55)和MVD计数均值[(55.42±6.93)个/HP],明显高于10例慢性胆囊炎组织(20.0%,10.0%)及其评分均值(0.13±0.35,0.62±0.20)和MVD计数均值[(20.04±5.92)个/HP],(P<0.01);胆囊癌组织中TIMP-2阳性表达率(41.9%)及其评分均值(1.52±1.41)则低于慢性胆囊炎组织阳性表达(90%)及其评分均值(3.40±0.84),(P<0.01)。EMMPRIN,TIMP-2,MMP-1的表达情况及MVD与胆囊癌的分化程度、肿瘤有无转移关系密切(P<0.05)。胆囊癌组织中EMMPRIN,MMP-1表达的评分与MVD之间存在着正相关关系;TIMP-2表达的评分与MVD之间存在着负相关关系。结论EMMPRIN,MMP-1的表达水平共同调控血管生成及影响胆囊癌的生物学行为和预后;TIMP-2在胆囊癌中可能通过抑制MMP-1的活性而抑制胆囊癌的发展。     

A comparison of Zoladex and DES in the treatment of advanced prostate cancer: results of a randomized, multicenter trial.

This open, prospective study was conducted to compare ZOLADEX (goserelin acetate implant) and diethylstilbestrol (DES) in the treatment of stage D2 prostate cancer. Sixty-seven patients were allocated to receive 3.6 mg of ZOLADEX every 28 days by subcutaneous injection (n = 48) or 3 mg of DES daily by oral administration (n = 19). Median serum levels of testosterone were reduced to castrate levels (less than 50 ng/dl) within one month of therapy in each group and remained so for up to 120 weeks. According to modified criteria of the National Prostatic Cancer Project, 88% of patients in the ZOLADEX group and 84% in the DES group were objective responders. Time to treatment failure and survival were not significantly different between groups, yet the confidence limits for the hazard ratios were wide. ZOLADEX was better tolerated than DES. We conclude that ZOLADEX is an alternative to DES in patients with stage D2 prostate cancer.     

Angiogenesis in renal cell carcinoma: Evaluation of microvessel density, vascular endothelial growth factor and matrix metalloproteinases

BACKGROUND: Angiogenesis, the growth of new blood vessels, has a critical role in tumor growth and metastasis. The purpose of this study was to investigate the involvement of angiogenesis and angiogenic factors in the pathogenesis of renal cell carcinoma (RCC). METHODS: Formalin-fixed and paraffin-embedded tissue blocks from 70 patients with RCC were studied. The situations of tumor angiogenesis were evaluated by assessing microvessel density (MVD) through CD31 immunostaining. The expression of vascular endothelial growth factor (VEGF), matrix metalloproteinase-2 (MMP-2) and metalloproteinase-9 (MMP-9) was detected immunohistochemically. RESULTS: The value of MVD ranged from 12.0 to 93.0 with a median of 39.91 in RCC. Of the 70 RCCs, the expression of VEGF was detected in 52 (74.3%), MMP-2 in 29 (41.4%) and MMP-9 in 19 (27.1%) cases. Statistical analysis revealed significant associations of the tumor stage with MVD, and the expression of VEGF and MMP-2 in RCC. Additionally, MVD was closely related to the expression of VEGF but was not related to the expression of MMP-2 and MMP-9 in RCC. CONCLUSION: The degree of angiogenesis may be closely related to the tumor progression of RCC. The expression of VEGF may be responsible for angiogenesis in RCC, and both VEGF and MMP-2 expression may function as tumor associated angiogenic factors in RCC.     

Preoperative administration of chlormadinone acetate reduces blood loss associated with transurethral resection of the prostate: a prospective randomized study

OBJECTIVES: To assess the effects of giving chlormadinone acetate (CMA) before surgery on blood loss associated with transurethral resection of the prostate (TURP), in a prospective randomized controlled study. PATIENTS AND METHODS: Candidates for TURP among patients with benign prostatic hyperplasia were randomized to either treatment with CMA (CMA+) or not (CMA-). In principle, CMA was started at least 28 days before TURP and continued until just before surgery. RESULTS: In all, 33 patients in the CMA+ (median duration of treatment 34.5 days) and 38 in the CMA- group were evaluable. The mean blood loss during TURP was less in the CMA+ (237.3 mL) than in the CMA- group (263.1 mL), but the difference was not significant. There was significantly less blood loss per gram of resected prostate tissue in the CMA+ (9.6 mL/g) than in the CMA- group (13.3 mL/g) (P < 0.05). Haematuria on the day of and the day after TURP was also significantly less severe in the CMA+ than in the CMA- group (P < 0.001 and P < 0.05, respectively). The mean microvessel density of resected prostate tissue was significantly less after CMA treatment (P < 0.001). CONCLUSIONS: CMA given for 1 month before TURP could reduce blood loss to some extent during and after TURP, and this may be related to a decrease in microvessel density.     

Survivin在原发性肝癌组织中的表达及与MVD的关系

目的 研究原发性肝癌组织中Survivin的表达及其与微血管密度(microvessel density,MVD)的关系,探讨它们之间及其与原发性肝癌临床病理特征的相互关系. 方法 用ABC免疫组化法测定56例原发性肝癌组织及癌旁组织中Survivin的表达水平及MVD. 结果 56例原发性肝癌组织中Survivin的阳性表达率(62.5%)和MVD计数均值[(55.43±6.72)个/HP],明显高于癌旁组织中Survivin的阳性表达率(14.3%)及MVD计数均值[(21.04±3.26)个/HP](P值均<0.05);Survivin的表达情况及MVD与原发性肝癌组织的分化程度、肿瘤有无转移、肿块直径、门静脉、肝静脉癌栓关系密切(P<0.05);原发性肝癌组织中Survivin表达评分与MVD之间存在正相关关系(P<0.01). 结论 Survivin和MVD的表达可能与原发性肝癌的发生、发展及血管生成密切相关.     

Comparison of the clinical outcome after hormonal therapy for prostate cancer between Japanese and Caucasian men

OBJECTIVE: To investigate the impact of race on the effectiveness of hormonal therapy in patients with prostate cancer, by comparing the outcomes of Caucasian men (CM) and Japanese-American men (JAM) treated with hormonal therapy at one institution. PATIENTS AND METHODS: Fifty-nine CM and 105 JAM with prostate cancer were treated with hormonal therapy at The Queen's Medical Center in Honolulu. Age, stage, Gleason score, race, and pretreatment PSA levels were abstracted. The Kaplan-Meier method was used to construct overall and cause-specific survival curves, which were compared using log-rank statistics. These factors were assessed as to their interdependence and correlation with the clinical course using a Cox proportional hazards regression model. RESULTS: Although there were no statistical differences in patient background, JAM who had received hormonal treatment had a better outcome than CM for overall and cause-specific survival rate (P = 0.001 and 0.036, respectively). Race was one of the significant prognostic factors in the multivariate analysis (P = 0.03). The findings suggest a difference in the effectiveness of hormonal therapy for prostate cancer in JAM living in Hawaii compared to CM. CONCLUSIONS: There were marked racial differences in clinical outcome after hormonal therapy between JAM and CM. A prospective study with more patients might be necessary to elucidate the differential effectiveness of hormonal therapy for prostate cancer in different races, especially between Japanese and Caucasians.     

检测微淋巴管及其密度和血管内皮生长因子C对结直肠癌的临床意义

目的探讨检测微淋巴管、微淋巴管密度(LMVD)和血管内皮生长因子C(VEGF-C)的表达对结直肠癌的临床意义。方法应用5′-核苷酸酶(5′-Nase)组织化学、SABC免疫组织化学(免疫组化)和RT-PCR检测80例结直肠癌组织和癌旁组织及30例结直肠正常组织的微淋巴管、LMVD和VEGF-C的表达,并随访、记录患者的临床病理参数和生存资料,分析其相关性。结果(1)结直肠癌、癌旁、正常结直肠组织的微淋巴管均被染成棕黄褐色。结直肠癌组织微淋巴管管腔封闭或无腔,为无功能淋巴管；癌旁组织微淋巴管丰富,管腔大,为功能性淋巴管。(2)癌旁组织LMVD为9．76±2．85,明显高于结直肠正常组织的5．49±．43(t=8．220,P＜0．01)；也高于癌组织的2．13±0．96(t= 15．118,P＜0．001)。(3)结直肠癌VEGF-C蛋白表达阳性率(48．8%)和相对表达量(1．09±1．20)明显高于正常结直肠组织(0和0),与VEGF-C mRNA表达一致；且VEGF-C表达与LMVD相关。(4) LMVD、VEGF-C表达与结直肠癌患者的年龄、性别、肿瘤部位大小、大体组织学类型无关(均P＞0．05)；与Dukes分期(P＜0．0001、P=0．0234)、淋巴结转移(P＜0．0001、P=0．0059)和生存期(P＜0．0001、P＜0．0001)密切相关。LMVD还与分化程度(P=0．0168)和肝肺血行转移(P=0．0088)相关。结论结直肠癌癌旁微淋巴管为功能性淋巴管；癌旁的功能性微淋巴管和增高的LMVD及肿瘤VEGF-C表达,可作为结直肠癌淋巴管生成的形态学特征、分子表型和判断结直肠癌患者淋巴转移及预后的重要指标。     

A prospective and randomized study of primary hormonal therapy for patients with localized or locally advanced prostate cancer unsuitable for radical prostatectomy: results of the 5-year follow-up

OBJECTIVE: To evaluate the effect of primary hormonal therapy for patients with localized and locally advanced prostate cancer. PATIENTS AND METHODS: Patients with stage T1b-T3 prostate cancer who were not scheduled for radical prostatectomy were allocated into two groups: group 1 (73 men) received luteinizing hormone-releasing hormone (LHRH) agonist monotherapy and group 2 (78 men) received LHRH agonist and chlormadinone acetate. Patients were followed using serum prostate specific antigen levels, prostate size and the detection of distant metastasis for 5 years. RESULTS: The median (range) follow-up was 78 (63-87) months. The 5-year progression-free survival rate was significantly higher in group 2 (68%) than in group 1 (47%). However, the overall and cause-specific survival rate at 5 years were similar in both groups, at 72% and 93% in group 1, and 64% and 89% in group 2, respectively. CONCLUSION: The overall survival rates of the both groups were no different from that of the normal Japanese population of the same age group. Although this study did not include an untreated group, i.e. watchful waiting, these results might indicate the usefulness of primary hormonal therapy in controlling localized and locally advanced prostate cancer. The 5-year observation period is still short and the study is continuing to determine the 10-year survival.     

Access of tumor-derived macromolecules and cells to the blood: an electron microscopical study of structural barriers in microvessel clusters in highly malignant primary prostate carcinomas

BACKGROUND: The neo-angiogenetic microvessels forming a major reactive stromal element in highly malignant prostate neoplasms may exhibit fine-structural features relevant to our understanding of the passage of macromolecules from tumor to blood, on the one hand, and of events facilitating the metastatic cascade, on the other hand. METHODS: Ensuring rapid, optimal fixation in buffered glutaraldehyde was a foremost concern. Thin parings from radical prostatectomy specimens of Gleason scores (GS) 5-9 were taken from the tumor and from the contralateral side of the gland, glutaraldehyde-fixed, diced to smaller than 1 mm(3), postfixed in osmium tetroxide, embedded in Epon, ultrathin-sectioned, contrasted with lead and uranyl salts, and viewed in a transmission electron microscope. RESULTS: In dysplastic tissue areas, intraductal microvessels located in gland ducts were occasionally observed, and found to be aggressively invasive and highly active in producing neo-angiogenetic sprouts. Closely spaced microvessel clusters contained almost exclusively neo-angiogenetic microvessels, which were in cell-cell contact with numerous ameboid migratory cells, some of which were likely to be tumor cells. In these microvessel clusters, all structural barriers hindering passage of tumor-derived molecules or cells to the blood were eliminated. CONCLUSION: In microvessel clusters, the ultrastructural equivalent of microvascular hotspots, tumor invasion of microvessels is facilitated, but equally microvessels are observed invading the gland duct epithelial walls. This reciprocal invasivity of tumor cells and microvascular endothelial cells generates ideal conditions for tumor products and metastatic cells to enter the blood.