Ishikura Kiyohide
Rinsho Byori. 2015 Jan;63(1):84-93.
Over the decades, prostate-specific antigen (PSA) has contributed to the early detection of and screening for prostate cancer (PCa). However, PSA is now in the spotlight due to issues of overdetection and subsequent overtreatment of PCa, causing a serious drawback in PSA-based screening. The challenge of a PSA assay for PCa detection is that the sensitivity is high, whereas the specificity is relatively low. With advancements in molecular biology and genomics, numbers of novel PCa markers has been discovered. One of the promising serum biomarkers is proPSA. proPSA is a pre-mature form of PSA. The molecules are fractions of free PSA, and [-2]proPSA contains 2 amino acids as N-terminus pro-peptides of PSA. Studies have shown the possibilities of using [-2] proPSA-related indices like the Prostate Health Index and %2PSA as tumor markers for diagnosis. [-2]proPSA-related indices have improved specificity compared to commonly used PSA and free PSA to detect PCa, while maintaining high-level sensitivity. Reports on clinical utilities of [-2]proPSA are rapidly increasing, and recent studies suggested the utility of [-2] proPSA-related indices for the enhancement of optimized treatment strategies and patient management. At present, several investigations which may reveal clinical utilities of [-2]proPSA are on-going in Japan. Attention: At the time of the submission of this article, [-2] proPSA had yet to be approved as an in vitro diagnostic test in Japan.
几十年来，前列腺特异性抗原（PSA）有助于前列腺癌（PCa）的早期检测和筛查。然而，由于PCa的过度检测及随后的过度治疗问题，PSA如今备受关注，这给基于PSA的筛查带来了严重缺陷。用于PCa检测的PSA检测面临的挑战在于其灵敏度高，而特异性相对较低。随着分子生物学和基因组学的发展，已发现了许多新型PCa标志物。有前景的血清生物标志物之一是前体PSA。前体PSA是PSA的一种前体形式。这些分子是游离PSA的组分，[-2]proPSA包含2个氨基酸作为PSA的N端前肽。研究表明，使用前列腺健康指数和%2PSA等与[-2]proPSA相关的指标作为诊断肿瘤标志物具有可能性。与常用的PSA和游离PSA相比，与[-2]proPSA相关的指标在检测PCa时提高了特异性，同时保持了高水平的灵敏度。关于[-2]proPSA临床应用的报道迅速增加，最近的研究表明，与[-2]proPSA相关的指标可用于优化治疗策略和患者管理。目前，日本正在进行多项可能揭示[-2]proPSA临床应用的研究。注意：在本文提交时，[-2]proPSA尚未在日本被批准作为体外诊断测试。
