Expression and Implication of Hypoxia Inducible Factor-1α in Prostate Neoplasm

Summary: To study the expression of hypoxia inducible factor-1α (HIF-1α) protein in prostate cancer (Pca) and its biological significance, the expression of HIF-1α was assayed by means of immunohistochemical technique in 42 prostate cancer, 12 prostatic intraepithelial neoplasm (PIN) and 9 normal prostate tissue (NP) specimens. Western blot was used to examine the expression of HIF-1α in prostate cancer cell line (PC-3M) induced by different oxygen tension. HIF-1α expression was positive in 33 Pca and 9 PIN specimens, and the positive rate of HIF-1α was higher in distant metastasis patients than in patients without metastasis of prostate cancer (P<0.05), while there was no expression of HIF-1α in NP. The level of HIF-1α in PC-3M significantly increased with the decrease of oxygen tension (P<0.01). Overexpression of HIF-1α is the preliminary event of the formation of Pca, which may induce carcinoma into malignant phenotype. Thus it may serve as an early diagnosis marker and the novel target for Pca treatment.

Commentary on: Mobley AJ, Lam YW, Lau KM, Pais VM, Lesperance JO, Steadman B, et al. Monitoring the serological Proteome Colon, the latest modality in prostate cancer detection. J Urol 2004; 172: 331-7.

This manuscript examines the utility, utilizing the Ciphergen Protein Biosystem II, to develop a fingerprint for the diagnosis of prostate cancer. The investigators compared samples from control individuals as well as those with prostate cancer. In doing so, they utilize several chip platforms on which to examine the resulting

KAI1/CD82 gene expression in benign prostatic hyperplasia and late-stage prostate cancer in Chinese

Aim: To evaluate KAII/CD82 expression in Chinese patients with benign prostatic hyperplasia (BPH) and late-stage carcinoma of prostate (CaP). Methods: Thirty Chinese patients with benign prostatic hyperplasia and 34 withCaP (adenocarcinoma clinical stage C and D) were analyzed by means of immunohistochemical methods. Results:The KAII/CD82 expression in BPH tissue was all positive, which was uniformly located on the glandular cell mem-brane at the cell-to-cell borders, but KAII/CD82 expression in metastasis CaP tissues was either significantly lower thanthat of BPH or negative, and the immunostaining pattern was not continuous. In late-stage CAP KAII/CD82 expressionwas correlated inversely to the pathological grade ( P < 0.05), but not to clinical stage ( P > 0.05). Conclusion:The authors believe that decreased and negative KAII/CD82 expression in late-stage CaP may be related to tumor pro-gression and metastasis, and appears to be a prognostic marker.

Targeted-cryosurgical ablation of the prostate with androgen deprivation therapy:quality of life in high-risk prostate cancer patients

Aim： To present preliminary results on health-related quality of life （QoL）, prostate-associated symptoms and therapeutic effects of targeted-cryosurgical ablation of the prostate （TCSAP） with androgen deprivation therapy （ADT） in high-risk prostate cancer （PCa） patients. Methods： Thirty-four men with high-risk PCa features underwent TCSAP, and ADT was added to improve the treatment outcomes. High-risk parameters were defined as either prostate-specific antigen （PSA） ≥ 10ng/mL, or Gleason score 〉 8, or both. The Genito-Urinary Group of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 （EORTC QLQ-C30） with prostate-cancer-specific module （QLQ-PR25） was used for evaluating morbidities and PSA levels were recorded every 3 months. PSA failure was defined as the inability to reach a nadir of 0.4 ng/mL or less. Results： Although it was not statistically significant, the global health status scores increased after TCSAP with ADT. The scores for five functional scales also became higher after treatment. The most prominent symptom after treatment was sexual dysfunction, followed by treatment-related and irritative voiding symptoms. Conclusion： TCSAP with ADT appears to be minimally invasive with high QoL except for sexual dysfunction. Long-term follow-up of PSA data and survival is necessary before any conclusions can be made on the efficacy of this promising new therapeutic modality in the treatment of PCa.

Formalized prediction of clinically significant prostate ：ancer： is it possible？

Greater understanding of the biology and epidemiology of prostate cancer in the last several decades have led to significant advances in its management. Prostate cancer is now detected in greater numbers at lower stages of disease and is amenable to multiple forms of efficacious treatment. However, there is a lack of conclusive data demonstrating a definitive mortality benefit from this earlier diagnosis and treatment of prostate cancer. It is likely due to the treatment of a large proportion of indolent cancers that would have had little adverse impact on health or lifespan if left alone. Due to this overtreatment phenomenon, active surveillance with delayed intervention is gaining traction as a viable management approach in contemporary practice. The ability to distinguish clinically insignificant cancers from those with a high risk of progression and/or lethality is critical to the appropriate selection of patients for surveillance protocols versus immediate intervention. This chapter will review the ability of various prediction models, including risk groupings and nomograms, to predict indolent disease and determine their role in the contemporary management of clinically localized prostate cancer.

Outcomes of T3a Prostate Cancer with Unfavorable Prognostic Factors Treated with Brachytherapy Combined with External Radiotherapy and Hormone Therapy

Objective To evaluate the outcomes of T3 a prostate cancer with unfavorable prognostic factors treated with permanent interstitial brachytherapy combined with external radiotherapy and hormone therapy.Methods From January 2003 to December 2008,38 patients classified as T3 a prostate cancer with unfavorable prognostic factors were treated with trimodality therapy(brachytherapy + external radiotherapy + hormone therapy).The prescription dose of brachytherapy and external radiotherapy were 110 Gy and 45 Gy,respectively.The duration of hormone therapy was 2-3 years.The endpoints of this study included biochemical failure-free survival(BFFS),distant metastasis-free survival(DMFS),cancer-specific survival(CSS),and overall survival(OS).Survival curves were calculated using the Kaplan-Meier method.The Log-rank test was used to identify the prognostic predictors for univariate analysis.Results The median follow-up was 71 months.The serum pre-treatment prostate-specific antigen(PSA) level ranged from 10.0 to 99.8 ng/ml(mean 56.3 ng/ml),the Gleason score ranged from 5 to 9(median 8),and the percentage of positive biopsy cores ranged from 10% to 100%(mean 65%).The 5-year BFFS,DMFS,CSS,and OS rates were 44%,69%,82%,and 76%,respectively.All biochemical failures occurred within 40 months.The percentage of positive biopsy cores was significantly correlated with BFFS,DMFS,and OS(all P=0.000),and the Gleason score with DMFS(P=0.000) and OS(P=0.001).Conclusions T3 a prostate cancer with unfavorable prognostic factors presents not so optimistic outcome.Hormone therapy should be applied to prolong the biochemical progression-free or metastasis-free survival.The percentage of positive biopsy cores and the Gleason score are significant prognostic factors.

Prostatic sarcoma of the Ewing family in a 33-year-old male e A case report and review of the literature

Ewing sarcoma is the second most common primary bone tumor seen in children and adolescents,typically presenting between 10 and 20 years of age.Extraosseous sarcomas of the Ewing family in adults are rare.We report a manifestation of this tumor entity in the periprostatic tissue of a 33-year-old male and discuss our treatment approach.Transrectal biopsy is a feasible and simple diagnostic tool for unclear pelvic masses.Multi-modal therapy and central registries are needed to gain knowledge of rare pelvic tumors like Ewing sarcoma.

Using CT imaging to delineate the prostatic apex for radiation treatment planning

Background and Objective: In computed tomography (CT)-based radiotherapy planning for prostate cancer, it is difficult to precisely delineate the prostatic apex because of its relationship with the urogenital diaphragm and bulbospongiosus musculature. In this retrospective study, we analyzed the magnetic resonance imaging (MRI) and CT scans of the patients with prostate cancer to investigate the relationship between the prostatic apex and the anatomic structure visible on CT, and to provide evidence for localizing the prostatic apex in radiotherapy planning. Methods: MRI and CT scans of 108 patients with prostate cancer were analyzed to measure the distances between the prostatic apex and the bottom of ischial tuberosities, the bottom of obturator foramen, the bottom of pubic symphysis, and the bulb of the penis. The volume of the prostate was measured to analyze its relationship with the localization of the prostatic apex. Results: The prostatic apex was located (13.1 ± 3.3) mm above the bulb of the penis, (11.0 ± 5.4) mm above the bottom of the obturator foramen, (31.3 ± 5.5) mm above the ischial tuberosities, and (7.1 ± 4.7) mm above the bottom of the symphysis pubis. There was no correlation between the size of the prostate and the localization of the prostatic apex. Conclusions: The variance of the distance between the prostatic apex and the bulb of the penis is smaller than that of the distance between the apex and bony anatomy. Delineating the target to 6 mm above the bulb of the penis can cover the prostatic apex in 95% of the patients with prostate cancer, delineating to the bottom of obturator foramen can cover the prostatic apex in 100% of the patients.

Undescended epididymo-testicular metastasis from prostatic carcinoma

Dear Sir, Metastasis of prostatic carcinoma to testis is un- common in the clinical situation, and the involvement of the epididymis is even rarer. Heidrich et al. [1] found only 80 cases of testicular involvement in prostate cancer in published reports. In 1993, Wiebe et al. [2] found only 14 previous cases of epididymal metastasis from prostatic carcinoma in published work. The simulta- neous involvement of testis and epididymis was reported by Suhler and Blanchard in 1980 [3]. To our knowledge, this was the first documented case of a prostatic carcinoma metastasizing to undescended testis and epididymis.

Analysis on chromosome 8 heterozygosity loss in humanprostate carcinoma and high grade prostaticintraepithelial neoplasia

Objective: To analysis the chromosome 8 heterozygosity loss in human prostate carcinoma and high grade prostatic intraepithelial neoplasia. Methods: Pure DNA was obtained from prostate neoplasms and normal tissues by tissue microdissection. The chromosome 8 heterozygosity loss was detected by PCR based micro-satellite polymorphism analysis technique using 14 pairs of microsatellite primers in 10 samples of prostate carcinoma and 10 samples of high grade prostatic intraepithelial neoplasia. Results: There were different frequencies of chromosome 8 heterozygosity loss in 10 samples of prostate carcinoma. 8p23.1-p23.2 and p21-p22 were two high frequency heterozygosity loss regions. Chromosome 8 heterozygosity loss was detected in 3 samples of high grade prostatic intraepithelial neoplasia. Conclusion: There were high frequency heterozygosity loss regions on chromosome 8 of prostate carcinoma, located at 8p23.1-p23.2 and p21-p22. The high grade prostatic intraepithelial neoplasia and prostate carcinoma share the same allelic loss on 8p. Tumor suppressor genes located at these two regions may be potentially involved in the initiation and progression of prostate carcinoma.

Prognostic role of platelet-to-lymphocyte ratio and neutrophil-to-lymphocyte ratio in patients with non-metastatic and metastatic prostate cancer:A meta-analysis and systematic review

Objective: To analyze data available in the literature regarding a possible prognostic value of the platelet-to-lymphocyte ratio (PLR) and neutrophil-to-lymphocyte ratio (NLR) in prostate cancer (PCa) patients stratified in non-metastatic and metastatic diseases.Methods: A literature search process was performed following the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines. In our meta-analysis, the pooled event rate estimated and the pooled hazard ratio were calculated using a random effect model.Results: Forty-two articles were selected for our analysis. The pooled risk difference for non-organ confined PCa between high and low NLR cases was 0.06 (95% confidence interval [CI]: −0.03-0.15) and between high and low PLR cases increased to 0.30 (95% CI: 0.16-0.43). In non-metastatic PCa cases, the pooled hazard ratio for overall mortality between high and low NLR was 1.33 (95% CI: 0.78-1.88) and between high and low PLR was 1.47 (95% CI: 0.91-2.03), whereas in metastatic PCa cases, between high and low NLR was 1.79 (95% CI: 1.44-2.13) and between high and low PLR was 1.05 (95% CI: 0.87-1.24).Conclusion: The prognostic values of NLR and PLR in terms of PCa characteristics and responses after treatment show a high level of heterogeneity of results among studies. These two ratios can represent the inflammatory and immunity status of the patient related to several conditions. A higher predictive value is related to a high NLR in terms of risk for overall mortality in metastatic PCa cases under systemic treatments.

肺癌患者血浆RASSF1A和BLU基因甲基化检测及临床意义

【目的】探讨肺癌患者外周血血浆中抑癌基因Ras相关结构域家族1A（RASSF1A）和BLU基因启动子的甲基化状态及其临床意义。【方法】利用巢式甲基化特畀性PCR（nMSP）法检测肺癌患者外周血血浆与正常人血浆中抑癌基因RASSF1A和BLU基因启动子的甲基化状态。【结果】58例肺癌患者血浆样品中分别发现22例（37．93％）RASSF1A基因启动子的异常甲基化和17例（29．31％）BLU基因启动予的异常甲基化，20例正常对照血浆中都未检测到RASSF1A和BLU基因启动子的异常甲基化，差异有显著性（P〈0．01）；但血浆中两基因甲基化检出率与患者性别、肺癌组织学分型及临床分期无明显相关性（P〉0．05）。【结论】利用nMSP法检测外周血血浆中RASSF1A和BLU基因启动子的甲基化，可为肺癌的筛查、早期诊断提供有用的信息。

1997版与2007版Partin tables预测国人前列腺癌病理分期准确性的比较

目的:验证2007版Partin tables对国人前列腺癌患者病理特征预测的准确性,并与1997版进行比较。方法:选本院2003年1月至2007年9月间,116例前列腺癌患者经根治术后病理确诊为前列腺腺癌,术前资料具备前列摘要目的:验证2007版Partin tables对国人前列腺癌患者病理特征预测的准确性,并与1997版进行比较。方腺特异抗原(prostate specific antigen,PSA),临床分期,穿刺活检Gleason评分。根据术后病理分为四型:器官局限(OC),包膜外侵犯(EPE),精囊侵犯(SVI)与淋巴结转移(LNI)。患者中93例符合2007版Partin tables预测入选标准,113例符合1997版预测入选标准,每例患者中分别应用两版Partintables预测术后病理特征的可能性,并通过工作特征曲线(ROC曲线)分析法研究两版Partintables的预测准确性并行比较。结果:根据2007版或1997版Partin tables预测入选标准,本组患者OC、EPE、SVI、LNI发生率分别为51%、15%、13%、22%或50%、16%、12%、23%。应用2007版Partin tables预测OC、EPE、SVI、LNI的ROC曲线下面积(AUC)分别为0.786、0.613、0.666和0.811,而应用1997版预测时分别为0.834、0.605、0.716、0.808。结论:两版Partin tables皆对OC及LNI有合理的预测价值(AUC>0.7),1997版Partin table比2007版显示出更佳的预侧准确性。

C57BL6小鼠前列腺癌原位移植瘤模型的建立及其MRI表现

目的采用瘤组织块原位移植法建立C57BL6小鼠前列腺癌原位移植瘤模型,观察其MRI表现,为研究前列腺癌的生长转移机制及其药物实验提供适宜的动物模型。材料与方法采用随机数字表法在35只6~8周龄C57BL6雄鼠中选出4只,将RM-1前列腺癌肿瘤细胞注射到小鼠背部皮下,每只注射0.1ml。待瘤组织块生长至1cm3时剥离出肿瘤组织,并裁剪为合适大小后,借助注射器种植到30只同周龄小鼠的前列腺内,建立小鼠前列腺癌原位移植瘤模型。第8天,从30只荷瘤鼠中采用随机数字表法选出6只,采用3.0TMR进行扫描。扫描结束后处死小鼠并取出瘤组织,将游标卡尺与MRI测量结果进行对比,最后进行病理学检查。结果建模1周后,29只实验小鼠可触及下腹部肿块;前列腺癌原位移植瘤T2WI呈中等信号,肿瘤向前膨出,将包膜挤出一定角度和高度提示包膜受累;病理切片可见大量瘤细胞呈条索状或散在成团杂乱分布于前列腺体间质中,肿瘤细胞形态不规则,呈多形性,核质比增大,可见异常病理性核分裂象。此模型成功率为96.7%(29/30),周围淋巴结转移率为96.7%(29/30),腹水形成率为96.7%(29/30),肝转移发生率为93.3%(28/30),肾转移发生率为0.33%(1/30),肉眼未见明显肺部转移,小鼠平均生存时间(12.7±1.8)d。MRI与游标卡尺测量肿瘤最大直径差异无统计学意义(P>0.05)。结论此种方法建立的前列腺癌原位模型操作简单、建模周期短、移植瘤成功率高,且其影像学表现与人类前列腺癌相似,可作为观察人类前列腺癌的动物模型。

Bloom解旋酶基因RNA干扰载体对前列腺癌PC3细胞的抑制作用

目的采用RNA干扰(RNAi)技术抑制前列腺癌PC3细胞系中Bloom解旋酶基因的表达,探讨Bloom解旋酶基因表达下调后对PC3细胞的抑制作用。方法使用实验室前期成功构建的两条针对于Bloom解旋酶基因的RNAi载体shRNA-1和shRNA-2转染前列腺癌PC3细胞,以未转染RNAi载体为对照组,分别在转染24、48、72h后通过MTT法检测细胞增殖情况,转染48h后通过Transwell小室法检验细胞侵袭、迁移能力,细胞划痕实验检测细胞迁移情况,Hoechst/PI双染法检测细胞凋亡情况。结果转染RNAi载体后,与未转染对照组相比,各实验时间点的转染组细胞增殖率降低(P<0.05),Transwell细胞侵袭和迁移实验中穿过室膜的细胞数与对照组比均减少(侵袭:119±24、118±30vs 227±38;迁移:122±13、121±47vs 277±32,P<0.05),划痕愈合率与划痕迁移距离均降低,48h时差异有统计学意义(P<0.05),而且细胞凋亡明显增加。结论以RNAi载体干扰Bloom解旋酶基因的表达可抑制前列腺癌PC3细胞的增殖、迁移和侵袭能力并促进其凋亡,为前列腺癌的靶向基因治疗提供了依据。

Individualized prostate biopsy strategy for Chinese patients with different prostate-specific antigen levels

Aim： To evaluate the best individualized prostate biopsy strategies for Chinese patients with suspected prostate cancer. Methods： The present study included 221 Chinese patients who underwent transrectal ultrasound guided prostate biopsies for the first time. All patients underwent the same 10-core biopsy protocol. In addition to the Hodge sextant technique, four more biopsies were obtained from the base and middle regions of bilateral peripheral zones. The differences between 10-core and sextant strategies in cancer detection among patients with different prostate specific anitgen （PSA） levels were evaluated. The relationship between PSA level, number of positive biopsy cores and organ-confined cancer rate in prostate cancer patients was also analyzed. Results： The overall prostate cancer detection rate was 40.7% in the 221 patients. The 10-core strategy increased cancer detection by 6.67% （6/90） in our patients （P 〈 0.05）. The increased cancer detection rates decreased significantly when the patient PSA level increased from 0-20 ng/mL to 20.1-50 ng/mL and 〉 50 ng/mL （P 〈 0.01）. The number of positive biopsy cores in prostate cancer patients increased significantly with increasing patient PSA level （P 〈 0.01）. The rate of organ-confined prostate cancer decreased significantly with increasing patient PSA level （P 〈 0.01）. Conclusion： The extended 10- core strategy is recommended for Chinese patients with PSA 〈 20 ng/mL and the sextant strategy is recommended for those with PSA〉 50 ng/mL. For patients with PSA ranging from 20.1 ng/mL to 50 ng/mL, the 10-core strategy should be applied in patients with life expectancy 〉 10 years and the sextant strategy should be applied in those with life expectancy 〈 10 years. （Asian J Androl 2008 Mar; 10： 325-331）

Stroma-epithelium crosstalk in prostate cancer

The critical role played by stroma-epithelium crosstalk in carcinogenesis and progression of prostate cancer has been increasingly recognized. These interactions are mediated by a variety of paracrine factors secreted by cancer cells and/or stromal cells. In human prostate cancer, reactive stroma is characterized by an increase in myofibroblasts and a corresponding amplification of extracellular matrix production and angiogenesis. Permanent genetic mutations have been reported in stromal cells as well as in tumour cells. Transforming growth factor-J3, vascular endothelial growth factor, platelet-derived growth factor and fibroblast growth factor signalling pathways are involved in the process of angiogenesis, whereas hepatocyte growth factor, insulin-like growth factor-l, epidermal growth factor, CXC12 and Interleukin-6 play active roles in the progression, androgen-independent conversion and distal metastasis of prostate cancer. Some soluble factors have reciprocal interactions with androgens and the androgen receptor （AR）, and can even activate AR in the absence of the androgen ligand. In this article, we review the complex interactions between cancer cells and the surrounding microenvironment, and discuss the potential therapeutic targets in the stromal compartment of prostate cancer.

An elevated serum miR-141 level in patients with bone-metastatic prostate cancer is correlated with more bone lesions

The skeleton is the most common metastatic organ in patients with prostate cancer （PCa）. Non-invasive biomarkers that can facilitate the detection and monitoring of bone metastases are highly desirable. We designed this study to assess the expression patterns of serum miR-141 in patients with bone-metastatic PCa. Serum samples were collected to measure the miR-141 level in 56 patients, including six with benign prostatic hyperplasia （BPH）, 20 with localized PCa and 30 with bone-metastatic PCa （10 with hormone-naive PCa, 10 with hormone-sensitive PCa and 10 with hormone-refractory PCa）. A bone scan was performed for each patient with PCa to assess the number of bone lesions. The quantification of serum miR-141 levels was assayed by specific TaqMan qRT-PCR. The results showed that serum miR-141 levels were elevated in patients with bone metastasis （P〈O.O01）. There was no statistically significant difference in the serum miR-141 levels between patients with BPH and patients with localized PCa. Using Kendall＇s bivariate correlation test, both the Gleason score and the number of bone-metastatic lesions were found to correlate with serum miR-141 levels （P=0.012 and P〈O.O01, respectively）. The serum miR-141 level was found to be positively correlated with alkaline phosphatase （ALP） level in patients with skeletal metastasis, using Pearson＇s bivariate correlation test. No relationship was found between the serum miR-141 level and the serum prostate-specific antigen （PSA） level. We concluded that serum miR-141 levels are elevated in patients with bone-metastatic PCa and that patients with higher levels of serum miR-141 developed more bone lesions. Furthermore, serum miR-141 levels are correlated with serum ALP levels but not serum PSA levels.

Radioiodine therapy for castration-resistant prostate cancer following prostate-specific membrane antigen promoter-mediated transfer of the human sodium iodide symporter

Radioiodine therapy, the most effective form of systemic radiotherapy available, is currently useful only for thyroid cancer because of the thyroid-specific expression of the human sodium iodide symporter （hNIS）. Here, we explore the efficacy of a novel form of gene therapy using prostate-specific membrane antigen （PSMA） promoter-mediated hNIS gene transfer followed by radioiodine administration for the treatment of castration-resistant prostate cancer （CRPC）. The androgen-dependent C33 LNCaP cell line and the androgen-independent C81 LNCaP cell line were transfected by adenovirus. PSMA promoter-hNIS （Ad.PSMApro-hNIS） or adenovirus.cytomegalovirus-hNIS containing the cytomegalovirus promoter （Ad.CMM-hNIS） or a control virus. The iodide uptake was measured in vitro. The in vivo iodide uptake by C81 cell xenografts in nude mice injected with an adenovirus carrying the hNIS gene linked to PSMA and the corresponding tumor volume fluctuation were assessed. Iodide accumulation was shown in different LNCaP cell lines after Ad.PSMApro-hNIS and Ad.CMV-hNIS infection, but not in different LNCaP cell lines after adenovirus.cytomegalovirus （Ad.CMV） infection. At each time point, higher iodide uptake was shown in the C81 cells infected with Ad.PSMApro-hNIS than in the C33 cells （P 〈 0.05）. An in vivo animal model showed a significant difference in 1311 radioiodine uptake in the tumors infected with Ad.PSMApro-hNIS, Ad.CMV-hNIS and control virus （P 〈 0.05） and a maximum reduction of tumor volume in mice infected with Ad.PSMApro-hNIS. These results show prostate-specific expression of the hNIS gene delivered by the PSMA promoter and effective radioiodine therapy of CRPC by the PSMA promoter-driven hNIS transfection.

Clinical significance of the leptin and leptin receptor expressions in prostate tissues

Aim： To evaluate the expression of leptin and leptin receptor in benign prostatic hyperplasia （BPH） and prostate cancer （PCa）, and to investigate whether they are associated with the development and progression of PCa. Methods： hnmunohistochemical staining was performed to examine the expression of leptin and leptin receptor in BPH and PCa. PCa was divided into three groups： localized PCa, locally advanced PCa and metastatic PCa. The positive staining was identified and the percentage of the positive staining was graded. We also assessed the relationship between both the Gleason score and body mass index （BMI） and PCa. Results： The percentage of the leptin expression in PCa was significantly higher than that in BPH （P 〈 0.01）. For the PCa group, the expressed levels of leptin showed a considerable correlation with localized PCa and metastatic PCa （P 〈 0.05）. Leptin receptor, however, did not reveal a definite difference between BPH and PCa. The expression of leptin indicated a significant difference between well-differentiated PCa （Gleason score ≤6） and poorly differentiated PCa （Gleason score 8-10） （P 〈 0.05）. The relation between the leptin expression level in PCa and the BMI was not remarkable （P = 0.447）. Conclusion： Our results suggest that leptin might have a promoting effect on the carcinogenesis and progression of PCa.