Joung Jae Young, Yang Seung Ok, Jeong In Gab, Han Kyung Suk, Seo Ho Kyung, Chung Jinsoo, Park Weon Seo, Lee Kang Hyun
Urologic Oncology Clinic, Institute and Hospital, National Cancer Center, 809 Madu-Dong, Ilnsan-Gu, Goyang, Gyonggi 410-769 Korea.
Int J Urol. 2007 Jul;14(7):635-43. doi: 10.1111/j.1442-2042.2007.01787.x.
To determine whether detection of prostate stem cell antigen (PSCA) expression has potential for molecular staging in prostate cancer (PCa), we examined the relationship between established prognostic factors, biochemical recurrence (BCR) and PSCA expression.
This study was comprised of 66 patients who underwent radical prostatectomy for the treatment of PCa. We employed reverse transcriptase-polymerase chain reaction (RT-PCR) to detect PSCA mRNA-bearing cells in peripheral blood, and used immunohistochemical (IHC) techniques to identify PSCA protein expression in microarrayed tissue.
PSCA-mRNA was detected in the peripheral blood of nine (13.6%) patients by RT-PCR. Whereas 3.2% of patients with low-grade disease were PSCA positive, 22.9% of patients with high-grade disease were PSCA positive (P = 0.030). There was also a significant relationship of RT-PCR PSCA positivity to whether or not the tumor was confined to the prostate. Whereas only 6.8% of patients with prostate-confined disease were RT-PCR PSCA positive, 27.3% of extraprostatic diseases were RT-PCR PSCA positive (P = 0.022). IHC studies of tumor tissue microarrays demonstrated that PSCA expression intensity was related to both extraprostatic extension (P = 0.014) and positive surgical margin (P = 0.053). Whereas 23.8% of prostate-confined diseases were high intensity, 54.5% of extraprostatic diseases were high intensity. BCR developed in seven patients (10.6%) during the follow-up period (median, 16.2 months; range, 9-25 months). Prognostic factors increasing the risk of BCR included: seminal vesicle invasion (P = 0.004), extraprostatic disease (P = 0.019), lymphovascular emboli (P = 0.036) and RT-PCR PSCA positivity (P = 0.004) in univariate analysis.
We were able to detect PSCA mRNA-bearing cells in peripheral blood by RT-PCR, and also identify PSCA protein expression in tumors by IHC analysis of tissue microarrays. RT-PCR PSCA positivity in peripheral blood may be a potential modality for molecular staging of PCa.
为了确定检测前列腺干细胞抗原（PSCA）表达对前列腺癌（PCa）分子分期是否具有潜在价值，我们研究了既定预后因素、生化复发（BCR）与PSCA表达之间的关系。
本研究纳入了66例行根治性前列腺切除术治疗PCa的患者。我们采用逆转录聚合酶链反应（RT-PCR）检测外周血中携带PSCA mRNA的细胞，并使用免疫组织化学（IHC）技术鉴定微阵列组织中的PSCA蛋白表达。
通过RT-PCR在9例（13.6%）患者的外周血中检测到PSCA-mRNA。低级别疾病患者中3.2%为PSCA阳性，而高级别疾病患者中22.9%为PSCA阳性（P = 0.030）。RT-PCR检测PSCA阳性与肿瘤是否局限于前列腺也存在显著关系。局限于前列腺的疾病患者中只有6.8%为RT-PCR PSCA阳性，而前列腺外疾病患者中27.3%为RT-PCR PSCA阳性（P = 0.022）。肿瘤组织微阵列的IHC研究表明，PSCA表达强度与前列腺外扩展（P = 0.014）和手术切缘阳性（P = 0.053）均相关。局限于前列腺的疾病中23.8%为高强度，而前列腺外疾病中54.5%为高强度。随访期间7例患者（10.6%）出现BCR（中位时间16.2个月；范围9 - 25个月）。单因素分析中，增加BCR风险的预后因素包括：精囊侵犯（P = 0.004）、前列腺外疾病（P = 0.019）、淋巴管栓子（P = 0.036）和RT-PCR PSCA阳性（P = 0.004）。
我们能够通过RT-PCR在外周血中检测到携带PSCA mRNA的细胞，并通过组织微阵列的IHC分析鉴定肿瘤中的PSCA蛋白表达。外周血中RT-PCR检测PSCA阳性可能是PCa分子分期的一种潜在方式。
