Nikseresht S, Shewell L K, Day C J, Jennings M P, Chittoory H, McCart Reed A E, Simpson P T, Lakhani S R, Nabiee R, Moore M, Khanabdali R, Hinch L M, Rice G E
INOVIQ Ltd, Notting Hill, 23 Normanby Road, VIC, Australia.
Institute for Glycomics, Griffith University, Gold Coast, QLD, Australia.
Breast Cancer Res Treat. 2025 Jun;211(3):605-615. doi: 10.1007/s10549-025-07672-z. Epub 2025 Mar 27.
This study aims to test the hypothesis that an enzyme-linked antibody-lectin sandwich assay for a glycovariant of CA15-3 can deliver better diagnostic performance, defined by classification accuracy, sensitivity and specificity, for breast cancer compared to an existing FDA-approved CA15-3 test.
A genetically engineered lectin (SubB2M) that specifically binds N-glycolylneuraminic acid (Neu5Gc) was used as a detection reagent in a CA15-3 capture antibody-lectin sandwich (neuCA15-3) assay. In a case: control cohort equivalence study the classification accuracy for the neuCA15-3 assay was determined and compared to an FDA-approved CA15-3 IVD test (Elecsys CA15-3 II, Roche Diagnostics).
Classification accuracy and AUC for neuCA15-3 were 81% and 0.886 ± 0.015 (standard error, n = 567) and for Elecsys CA15-3 II, 55% and 0.642 ± 0.023 (n = 558), respectively. At a threshold cut-off serum concentration of 23.6 units/ml, overall breast cancer classification accuracy of the neuCA15-3 was 81% (compared to 55% for the comparator assay, p < 0.001). At 95% specificity, the sensitivity of the neuCA15-3 assay was 69.5%, significantly greater than the comparator assay (11.9%, p < 0.001). neuCA15-3 concentrations did not vary significantly with breast cancer receptor subtype or comorbidities tested.
The diagnostic performance of neuCA15-3 was substantially improved by specifically targeting both a CA15-3 protein epitope and a pan-cancer glycan (Neu5Gc) epitope (the specific binding target of SubB2M). The reporter signal generated depends on the colocalization of the cancer antigen protein epitope and the aberrant sialylation of the protein, thus increasing the assay specificity. The presence of multiple Neu5Gc lectin-binding sites per glycoprotein molecule increases signal generation and assay sensitivity. The inclusion of additional cancer biomarkers in a multivariate index assay format may further increase diagnostic performance for breast cancer.
本研究旨在验证以下假设：与现有的美国食品药品监督管理局（FDA）批准的CA15-3检测方法相比，用于检测CA15-3糖变体的酶联抗体-凝集素夹心检测法在乳腺癌诊断中能提供更好的诊断性能，以分类准确率、敏感性和特异性来定义。
一种特异性结合N-羟乙酰神经氨酸（Neu5Gc）的基因工程凝集素（SubB2M）被用作CA15-3捕获抗体-凝集素夹心（neuCA15-3）检测法中的检测试剂。在一项病例对照队列等效性研究中，确定了neuCA15-3检测法的分类准确率，并与FDA批准的CA15-3体外诊断检测法（Elecsys CA15-3 II，罗氏诊断公司）进行比较。
neuCA15-3的分类准确率和曲线下面积（AUC）分别为81%和0.886±0.015（标准误，n = 567），而Elecsys CA15-3 II的分类准确率和AUC分别为55%和0.642±0.023（n = 558）。在血清浓度阈值为23.6单位/毫升时，neuCA15-3对乳腺癌的总体分类准确率为81%（相比之下，对照检测法为55%，p < 0.001）。在95%的特异性下，neuCA15-3检测法的敏感性为69.5%，显著高于对照检测法（11.9%，p < 0.001）。neuCA15-3浓度在检测的乳腺癌受体亚型或合并症方面没有显著差异。
通过特异性靶向CA15-3蛋白表位和泛癌聚糖（Neu5Gc）表位（SubB2M的特异性结合靶点），neuCA15-3的诊断性能得到了显著改善。产生的报告信号取决于癌症抗原蛋白表位的共定位和蛋白质的异常唾液酸化，从而提高了检测的特异性。每个糖蛋白分子中多个Neu5Gc凝集素结合位点的存在增加了信号产生和检测的敏感性。在多变量指标检测形式中纳入其他癌症生物标志物可能会进一步提高乳腺癌的诊断性能。
