CRISP3 glycoprotein: a good biomarker for prostate cancer?

ABSTRACT Introduction: Cysteine-rich secretory protein 3 (CRISP3) is expressed at low levels in normal human prostate but often overexpressed in prostate cancer (PCa). The relevance of this overexpression for the malignancy of PCa is still unclear. The prognostic value of the currently used prostate specific antigen (PSA) test can be misleading under certain circumstances, resulting in overtreatment of indolent tumors. New biomarkers are needed to reduce overtreatment and improve quality of life of men. Objective: Evaluate if CRISP3 expression could be a good biomarker for PCa. Methods: CRISP3 expression was determined by immunohistochemistry in tissue sections of prostate cancer from twenty-five patients subjected to radical prostatectomy. Gleason grading system was used as prognostic indicator and the staging of PCa was defined using the TNM system. Clinical parameters and PSA levels before and after surgery were determined. Results: CRISP3 expression was strong in 14 (56%), moderate in four (16%) and weak in seven (28%) specimens. There was no correlation between the intensity of CRISP3 expression and pre- and post-treatment PSA levels. Fifteen (60%) of PCa biopsies showed extension of the primary tumor pT2. Seven patients (28%) showed Gleason score higher than 7; thirteen (52%) equal to 7, and five (20%) lower than 7. There were no significant statistical differences between Gleason score and CRISP3 expression. Conclusion: CRISP3 is expressed in prostate cancer at different levels. Additional studies are required to better evaluate if CRISP3 could be used as a biomarker.

摘要
引言：富含半胱氨酸分泌蛋白3（Cysteine-rich secretory protein 3，CRISP3）在正常人体前列腺中呈低表达，但在前列腺癌（prostate cancer，PCa）中常出现过表达。目前，该过表达与前列腺癌恶性程度的相关性尚不明确。当前临床广泛使用的前列腺特异性抗原（prostate specific antigen，PSA）检测在特定情境下其预后价值可能存在误导，会导致惰性肿瘤患者接受过度治疗，因此亟需新型生物标志物以减少过度治疗、改善男性患者的生活质量。
目的：评估CRISP3表达能否作为前列腺癌的有效生物标志物。
方法：通过免疫组织化学法检测25例行根治性前列腺切除术患者的前列腺癌组织切片中CRISP3的表达水平。以格里森分级系统（Gleason grading system）作为预后判定指标，采用TNM分期系统（TNM staging system）明确前列腺癌的临床分期，并检测患者手术前后的临床参数与PSA水平。
结果：14例（56%）标本的CRISP3表达呈强阳性，4例（16%）呈中等阳性，7例（28%）呈弱阳性。CRISP3表达强度与患者术前、术后的PSA水平均无相关性。15例（60%）前列腺癌活检标本的原发肿瘤分期为pT2。7例（28%）患者的格里森评分高于7分，13例（52%）为7分，5例（20%）低于7分。格里森评分与CRISP3表达水平之间未发现显著统计学差异。
结论：CRISP3在前列腺癌中呈现不同水平的表达。后续需开展更多研究，以进一步评估CRISP3是否可作为前列腺癌的生物标志物。