Department of Urology, Renmin Hospital of Wuhan University, Wuhan 430060, Hubei, China.
Sensors (Basel). 2012;12(5):5461-70. doi: 10.3390/s120505461. Epub 2012 Apr 27.
Quantum dots (QDs) are a new class of fluorescent labeling for biological and biomedical applications. In this study, we detected prostate stem cell antigen (PSCA) expression correlated with tumor grade and stage in human prostate cancer by QDs-based immunolabeling and conventional immunohistochemistry (IHC), and evaluated the sensitivity and stability of QDs-based immunolabeling in comparison with IHC. Our data revealed that increasing levels of PSCA expression accompanied advanced tumor grade (QDs labeling, r = 0.732, p < 0.001; IHC, r = 0.683, p < 0.001) and stage (QDs labeling, r = 0.514, p = 0.001; IHC, r = 0.432, p = 0.005), and the similar tendency was detected by the two methods. In addition, by comparison between the two methods, QDs labeling was consistent with IHC in detecting the expression of PSCA in human prostate tissue correlated with different pathological types (K = 0.845, p < 0.001). During the observation time, QDs exhibited superior stability. The intensity of QDs fluorescence remained stable for two weeks (p = 0.083) after conjugation to the PSCA protein, and nearly 93% of positive expression with their fluorescence still could be seen after four weeks.
量子点（QDs）是一类新的荧光标记物，可用于生物和生物医学应用。在这项研究中，我们通过基于 QD 的免疫标记和传统免疫组织化学（IHC）检测了人前列腺癌中与肿瘤分级和分期相关的前列腺干细胞抗原（PSCA）的表达，并评估了 QD 免疫标记与 IHC 相比的灵敏度和稳定性。我们的数据显示，PSCA 表达水平的升高伴随着肿瘤分级（QD 标记，r = 0.732，p < 0.001；IHC，r = 0.683，p < 0.001）和分期（QD 标记，r = 0.514，p = 0.001；IHC，r = 0.432，p = 0.005）的增加，两种方法均显示出相似的趋势。此外，通过两种方法的比较，QD 标记与 IHC 在检测人前列腺组织中与不同病理类型相关的 PSCA 表达方面具有一致性（K = 0.845，p < 0.001）。在观察期间，QD 表现出更好的稳定性。QD 与 PSCA 蛋白结合后，其荧光强度在两周内保持稳定（p = 0.083），四周后仍有近 93%的阳性表达可见。
