Barrabés Sílvia, Llop Esther, Ferrer-Batallé Montserrat, Ramírez Manel, Aleixandre Rosa N, Perry Antoinette S, de Llorens Rafael, Peracaula Rosa
Biochemistry and Molecular Biology Unit, Department of Biology, University of Girona, Campus de Montilivi, 17003 Girona, Spain; Girona Biomedical Research Institute (IDIBGI), Dr. J. Trueta University Hospital, 17007 Girona, Spain.
Girona Biomedical Research Institute (IDIBGI), Dr. J. Trueta University Hospital, 17007 Girona, Spain; Clinic Laboratory, Dr. J. Trueta University Hospital, 17007 Girona, Spain.
Clin Chim Acta. 2017 Jul;470:97-102. doi: 10.1016/j.cca.2017.05.009. Epub 2017 May 8.
The levels of core fucosylation and α2,3-linked sialic acid in serum Prostate Specific Antigen (PSA), using the lectins Pholiota squarrosa lectin (PhoSL) and Sambucus nigra agglutinin (SNA), can discriminate between Benign Prostatic Hyperplasia (BPH) and indolent prostate cancer (PCa) from aggressive PCa. In the present work we evaluated whether these glycosylation determinants could also be altered in urinary PSA obtained after digital rectal examination (DRE) and could also be useful for diagnosis determinations. For this purpose, α2,6-sialic acid and α1,6-fucose levels of urinary PSA from 53 patients, 18 biopsy-negative and 35 PCa patients of different aggressiveness degree, were analyzed by sandwich ELLA (Enzyme Linked Lectin Assay) using PhoSL and SNA. Changes in the levels of specific glycosylation determinants, that in serum PSA samples were indicative of PCa aggressiveness, were not found in PSA from DRE urine samples. Although urine is a simpler matrix for analyzing PSA glycosylation compared to serum, an immunopurification step was necessary to specifically detect the glycans on the PSA molecule. Those specific glycosylation determinants on urinary PSA were however not useful to improve PCa diagnosis. This could be probably due to the low proportion of PSA from the tumor in urine samples, which precludes the identification of aberrantly glycosylated PSA.
使用鳞盖伞凝集素（PhoSL）和黑接骨木凝集素（SNA）检测血清前列腺特异性抗原（PSA）中的核心岩藻糖基化水平和α2,3连接的唾液酸水平，可以区分良性前列腺增生（BPH）、惰性前列腺癌（PCa）和侵袭性PCa。在本研究中，我们评估了这些糖基化决定簇在直肠指检（DRE）后获得的尿PSA中是否也会发生改变，以及是否对诊断有帮助。为此，我们使用PhoSL和SNA，通过夹心ELLA（酶联凝集素测定）分析了53例患者尿PSA中的α2,6-唾液酸和α1,6-岩藻糖水平，其中18例活检阴性，35例不同侵袭程度的PCa患者。在DRE尿液样本的PSA中未发现特定糖基化决定簇水平的变化，而在血清PSA样本中这些变化表明PCa的侵袭性。尽管与血清相比，尿液是分析PSA糖基化的更简单基质，但需要进行免疫纯化步骤以特异性检测PSA分子上的聚糖。然而，尿PSA上的那些特定糖基化决定簇对改善PCa诊断并无帮助。这可能是由于尿液样本中肿瘤来源的PSA比例较低，从而无法识别异常糖基化的PSA。
