前列腺特异性抗原人类激肽释放酶2和前列腺特异的膜抗原在前列腺癌患者外周血表达的临床意义

目的　探讨检测前列腺癌微转移的灵敏和特异性指标。方法　从 5 1例前列腺癌、33例前列腺增生 (BPH)患者及 32名正常人的外周血中分离单个核细胞 ,用巢式RT PCR方法检测其中前列腺上皮细胞前列腺特异性抗原 (PSA)、人类激肽释放酶 2 (hK2 )和前列腺特异的膜抗原 (PSMA)的表达。结果　PSA、hK2和PSMA在前列腺癌患者外周血中检出的阳性率分别为 5 2 .9%、4 3.1%和6 4 .7% ;正常人和BPH患者假阳性率分别为 6 .2 %、7.7%和 4 .6 % ,3项指标差异均有显著性 (P <0 .0 1)。各临床分期 (局限癌、侵袭性癌和转移癌 )间 ,PSA和hK2的阳性检出率差异无显著性 ;PSMA在各期前列腺癌中阳性检出率均较PSA和hK2高 ,且随临床分期进展 ,其阳性检出率亦增加 (P <0 .0 5 )。结论PSMA对前列腺癌诊断、治疗方案的选择及预后评估较PSA和hK2有更大的价值     

Effect of exogenous testosterone replacement on prostate-specific antigen and prostate-specific membrane antigen levels in hypogonadal men

Previous studies have suggested that serum prostate-specific antigen (PSA) levels are under androgenic influence, especially in patients with adenocarcinoma of the prostate. PSMA (prostate-specific membrane antigen) is thought to reflect hormonal or clonal resistance or an independence with respect to testosterone regulation. The influence of testosterone on serum PSA expression in normal men is not clear. We studied the effect of exogenous testosterone administration on the serum levels of PSA and PSMA in hypogonadal men. Serial serum PSA, serum PSMA by Western blot, and serum total testosterone levels were obtained at intervals of every 2–4 weeks in 10 hypogonadal men undergoing treatment with exogenous testosterone, delivered as testosterone enanthate injection or by testosterone patch. Linear and quadratic orthogonal polynomial scores were calculated for PSMA, PSA, and testosterone. A 2-tailed, paired t-test failed to demonstrate a significant correlation between serum PSA (linear P = 0.432, quadratic P = 0.290) or PSMA (linear P = 0.162, quadratic P = 0.973) and serum testosterone levels. This study suggests that in hypogonadal men, neither PSMA nor PSA expression is testosterone-dependent.     

前列腺特异性膜抗原和前列腺特异性抗原表达强度与前列腺癌Gleason评分之间的相关性研究

目的研究前列腺特异性膜抗原(PSMA)和前列腺特异性抗原(PSA)的表达强度与前列腺癌Gleason评分之间的相关性。方法制备抗PSMA膜外段表位的单克隆抗体,应用免疫组织化学方法检测前列腺癌中PSMA的表达,统计分析其与Gleason评分之间的相关性,并和PSA与Gleason评分之间的相关性进行对比。结果制备出8株分泌抗PSMA膜外段表位的单抗的杂交瘤细胞株。免疫组化结果表明,PSMA的表达强度与前列腺癌的Gleason评分之间存在相关性。在分化差的前列腺癌中,PSMA水平高于分化中等和分化良好的前列腺癌(P<0.01),而PSA在前列腺癌中的表达无明显差异(P>0.05)。结论PSMA表达水平在分化差的前列腺癌中明显升高,与Gleason评分存在相关性,可以作为前列腺癌的Gleason分级的标记物,提示PSMA可以作为对激素疗法效果不敏感的低分化前列腺癌抗体介导的免疫治疗靶点。     

前列腺特异性膜抗原在前列腺癌患者外周血和组织中的表达及意义

目的探讨前列腺特异性膜抗原（PSMA）在前列腺癌患者（PCa）外周血和组织中的表达及其与肿瘤病理分级和临床分期之间的关系。方法采用RT-PCR方法检测前列腺特异性膜抗原（PSMA）在前列腺癌和良性增生患者外周血清中的表达;采用免疫组化法观察PSMA在前列腺不同病变组织中的表达。前列腺癌28例,前列腺上皮内瘤（PIN）7例,良性前列腺增生（BPH）30例。结果血清学检测显示PSMA mRNA在前列腺癌和良性病变组（包括PIN和BPH）患者外周血中阳性率分别为67.9%和8.1%,两者差异具有显著性（P〈0.01）。在局限性癌、局部进展性癌和远处转移癌患者外周血肿瘤细胞中,PSMA mRNA的阳性率分别为58.3%、66.7%和85.7%,随前列腺癌临床分期的进展而逐渐递增（P〈0.05）。在高分化、中分化和低分化前列腺癌中,PSMA mRNA的阳性率分别为87.5%、62.5%和50%,肿瘤分化越差,其阳性率越低（P〈0.05）。组织学检测显示PSMA在PCa、PIN、BPH三种不同前列腺病变组织中的阳性率分别为60.7%、28.6%和20.0%（P〈0.05）,在高、中、低分化前列腺癌组织中PSMA的阳性率分别为100.0%、50.0%和25.0%,与肿瘤Gleason评分之间呈负相关（P〈0.05）。在局限性癌、局部进展性癌和远处转移癌患者肿瘤组织中,PSMA的阳性率分别为58.3%（7/12）、77.8%（7/9）和42.9%（3/7）（P〉0.05）。结论PSMA在前列腺癌组织中明显高表达,并且表达量与前列腺癌临床分期和分化程度（组织学分级）密切相关;检测PSMA可能对前列腺癌诊断、治疗方案的选择及预后评估具有重要价值。     

Prognostic value of surgical margin status for biochemical recurrence following radical prostatectomy

OBJECTIVE: We evaluated the preoperative parameters to predict a positive surgical margin (SM) at radical prostatectomy for patients with prostate cancer. In addition, the prognostic factors for biochemical recurrence were determined in patients with positive SMs. METHODS: We retrospectively analysed 238 patients with prostate cancer who underwent retropubic radical prostatectomy and bilateral pelvic lymph node dissection from May 1985 to July 2005 in our hospital. Biochemical recurrence was defined as an increase of undetectable prostate-specific antigen (PSA) to 0.2 ng/ml or greater. RESULTS: Of the 238, 82 patients (34.4%) had positive SMs. On multivariate analysis, preoperative PSA (>/=10 ng/ml), clinical T stage (>/=T2a) and the positive core rate (>/=35%) were parameters that could predict a positive SM. During the median follow-up of 31.2 months, 48 patients (20.2%) developed biochemical recurrence. The 5-year biochemical progression-free survival rates were 81.7% and 62.6% in patients with negative and positive SMs, respectively (P < 0.001). In the Cox proportional hazards model, preoperative PSA of >/=20 ng/ml and a pathological T stage of pT3a/pT3b were significant risk factors for biochemical recurrence in patients with positive SMs. CONCLUSIONS: SM status at radical prostatectomy depends on preoperative PSA, clinical stage and the positive core rate. Patients with a positive SM had a higher risk for biochemical recurrence than those with a negative one. Patients with a positive margin had a higher risk for biochemical recurrence if they exhibited preoperative PSA of >/=20 ng/ml and/or pathological T stage of pT3a/pT3b.     

Molecular staging of pelvic surgical margins after radical prostatectomy: comparison of RT-PCR for prostate-specific antigen and telomerase activity

The further course of prostate cancer (PC) after radical prostatectomy (RPX) is decisively influenced by the local tumor stage. Although it is now possible to assess the risk of local recurrence from the histopathology, precise predictions cannot be made. A more accurate evaluation would be desirable, mainly for early planning of adjuvant therapy. We assessed the detection of telomerase activity using the Telomeric Repeat Amplification Protocol in surgical margins compared to RT-PCR-supported prostate-specific antigen (PSA) mRNA detection and conventional histopathological examination. We examined 95 patients with local PC during RPX and 16 patients with muscle-invasive transitional bladder cancer who underwent radical cystectomy. After RPX or RCX biopsies were obtained from 4 or 3 defined areas of the prostatic fossa and processed by TRAP assay for telomerase activity and by RT-PCR for PSA using a standard protocol. Five of 48 patients (10.4%) with organ-confined prostate cancer (pT2) and 7 of 47 patients (14.9%) with locally advanced PC (>pT2) had positive detection of telomerase activity in at least one positive specimen. In contrast to RT-PCR for PSA mRNA and histological findings for organ-confined and locally advanced disease, detection of telomerase activity yielded no statistically significant correlation to clinical parameters. Only PC-patients with positive histopathological margins had a positive correlation between detection of telomerase activity and high Gleason scores (r=0.65, p=0.022). Based on the results obtained and the current state of knowledge, measurement of telomerase activity must be considered less sensitive than RT-PCR for PSA mRNA in surgical margins, although tumor specificity should theoretically be higher. It is not even sure at the present time whether a combination of both methods offers any recognizable advantage over PSA mRNA detection alone. The value of the results obtained in this study will have to be assessed in a further follow-up to determine whether patients with positive molecular detection have an increased risk of local recurrence.     

Radical prostatectomy for prostate cancer patients with prostate-specific antigen >20 ng/ml

OBJECTIVE: Prostate cancer patients with prostate-specific antigen (PSA) >20 ng/ml are at high risk of progression after radical prostatectomy. Comparison has seldom been made between the outcomes of patients with PSA 20.1-50 ng/ml and those with PSA >50 ng/ml after radical prostatectomy. We retrospectively analyzed the outcomes of these two groups. METHODS: From 1993 to 2002, 60 prostate cancer patients receiving radical prostatectomy were enrolled in this study. Thirty-seven patients with PSA 20.1-50 ng/ml were assigned to Group I. Twenty-three patients with PSA >50 ng/ml were assigned to Group II. Preoperatively, Group II had greater PSA and PSA density than Group I (P < 0.0001). Group II had higher biopsy Gleason score and clinical stage than Group I (P < 0.05). Pathological categories and outcomes of both groups were compared. RESULTS: Group II had higher Gleason score and tumor volume than Group I (P < 0.05). The incidence of organ-confined diseases was 29.7% in Group I and 0% in Group II (P < 0.05). Group II had higher incidence of extracapsular tumor extension, positive surgical margin and lymph node involvement than Group I (P < 0.05). The incidence of postoperative PSA >0.01 ng/ml and PSA failure were higher in Group II than Group I (P < 0.05). Need for adjuvant treatment and death from prostate cancer was similar in both groups. CONCLUSION: Patients with PSA >50 ng/ml had a poorer prognosis than patients with PSA 20.1-50 ng/ml. Those with PSA >50 ng/ml had shorter freedom from PSA failure survivals than those with PSA 20.1-50 ng/ml (P = 0.004). Classification of high-risk prostate patients into two sub-groups with PSA 20.1-50 ng/ml and PSA >50 ng/ml should be considered.     

Risk assessment for biochemical recurrence prior to radical prostatectomy: significant enhancement contributed by human glandular kallikrein 2 (hK2) and free prostate specific antigen (PSA) in men with moderate PSA-elevation in serum

Most models to predict biochemical recurrence (BCR) of prostate cancer use pretreatment serum prostate-specific antigen (PSA), clinical stage and prostate biopsy Gleason grade. We investigated whether human glandular kallikrein 2 (hK2) and free prostate-specific antigen (fPSA) measured in pretreatment serum enhance prediction. We retrospectively measured total PSA (tPSA), fPSA and hK2 in preoperative serum samples from 461 men with localized prostate cancer treated with radical prostatectomy between 1999 and 2001. We developed a regression model to predict BCR using preoperative tPSA, clinical stage and biopsy Gleason grade. We then compared the predictive accuracy of this "base" model with a model with fPSA and hK2 as additional predictors. BCR was observed in 90 patients (20%), including 48 patients with a pretreatment tPSA < or = 14 ng/ml (13%), and 28 patients (10%) with a pretreatment tPSA < or = 10 ng/ml. Overall, the predictive accuracy of the base model (bootstrap-corrected concordance index of 0.813) was not improved after the addition of fPSA or hK2 (0.818). However, for men with moderate tPSA-elevation (tPSA < or = 10 ng/ml), addition of fPSA and hK2 data increased predictive accuracy (from a base model concordance index of 0.756-0.815, p = 0.005). The improvement in accuracy was not sensitive to the threshold for "moderately elevated" PSA. For patients with a moderate tPSA-elevation (tPSA < or = 10 ng/ml), which closely corresponds to concurrent disease demographics, BCR-prediction was enhanced when fPSA and hK2 were added to the conventional model. Measurements of fPSA and hK2 improve on our ability to counsel patients prior to treatment as to their risk of BCR.