Tilli Tatiana M, Silva Eloísio A, Matos Lívia C, Faget Douglas V, Dias Bianca F P, Vasconcelos Juliana S P, Yokosaki Yasuyuki, Gimba Etel R P
Programa de Medicina Experimental and Biologia Celular and Post Graduation Program in Oncology, Coordenação de Pesquisa, Instituto Nacional de Câncer, Rio de Janeiro.
Oncol Lett. 2011 Jan;2(1):109-114. doi: 10.3892/ol.2010.211. Epub 2010 Nov 23.
Anti-tumor antibodies act as biomarkers for the early diagnosis of prostate cancer (PCa). Osteopontin (OPN) is overexpressed in PCa cells and contributes to the progression of the disease. This study aimed to evaluate whether OPN evokes a humoral immune response in PCa patients and whether the reactivity levels of anti-OPN antibodies may be used to better differentiate PCa from benign and healthy donor plasma samples. Plasma samples from biopsy-proven PCa patients (29), benign prostate hyperplasia (BPH) (18) and control healthy donors (HD) (30) were tested by immunoblots using the recombinant human OPN. The frequency of anti-OPN antibodies was significantly higher in PCa (66%) plasma samples as compared to BPH (33%) and HD controls (10%). Anti-OPN antibodies were detected in a high proportion of plasma samples from patients with a Gleason score of less than 6 (57%), prostate-specific antigen levels lower than 10 ng/ml (67%) and pT2 organ-confined disease (70%), suggesting that anti-OPN antibodies may be used as an early serum marker for PCa. To the best of our knowledge, this is the first description of OPN as a tumor autoantigen and one of the most reactive individual autoantigens described thus far. These data support the inclusion of OPN in a multiplex of tumor antigens in order to perform antibody profiling in PCa as well as in other malignancies overexpressing OPN.
抗肿瘤抗体可作为前列腺癌（PCa）早期诊断的生物标志物。骨桥蛋白（OPN）在PCa细胞中过表达，并促进疾病进展。本研究旨在评估OPN是否能在PCa患者中引发体液免疫反应，以及抗OPN抗体的反应水平是否可用于更好地区分PCa与良性及健康供体的血浆样本。使用重组人OPN通过免疫印迹法检测经活检证实的PCa患者（29例）、良性前列腺增生（BPH）患者（18例）和健康对照者（HD）（30例）的血浆样本。与BPH（33%）和HD对照组（10%）相比，PCa血浆样本中抗OPN抗体的频率显著更高。在Gleason评分小于6（57%）、前列腺特异性抗原水平低于10 ng/ml（67%）和pT2器官局限性疾病（70%）的患者的高比例血浆样本中检测到抗OPN抗体，这表明抗OPN抗体可作为PCa的早期血清标志物。据我们所知，这是首次将OPN描述为肿瘤自身抗原，也是迄今为止描述的反应性最强的单个自身抗原之一。这些数据支持将OPN纳入多种肿瘤抗原中，以便在PCa以及其他过表达OPN的恶性肿瘤中进行抗体谱分析。
