Confirming the tumor origin is often a diagnostic challenge in pathology and carries significant therapeutic impacts. Cytokeratin 7, estrogen receptor, and GATA binding protein 3 (GATA3) are well-established diagnostic markers frequently used to support a tumor's breast origin. However, their specificities still have room to improve. Many nonbreast tumors express cytokeratin 7 and estrogen receptor, and urothelial tumors frequently express GATA3. There is a practical need for a new breast lineage marker that is sensitive and specific. Wnt family member proteins play critical roles in embryo development, tissue homeostasis and tumor development through β-catenin dependent and independent pathways. The current study evaluated Wnt9b and GATA3 expression in 163 primary breast cancers, 63 metastatic breast cancers, and 525 nonbreast epithelial tumors. The positive rates of Wnt9b and GATA3 in primary breast cancer were both 98.7%. The positive rates in metastatic breast cancer were 87.3% for Wnt9b and 96.8% for GATA3. For nonbreast tumors, including 64 cases of urothelial carcinoma, Wnt9b was negative in all except salivary gland carcinomas. The study demonstrated that Wnt9b is a breast cancer marker with similar sensitivity as GATA3 but with greater specificity than GATA3 and may ultimately become a useful diagnostic tool in routine surgical pathology practice.

中文翻译：

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Wnt 家族成员 9b (Wnt9b) 是一种新的乳腺癌敏感特异性标记物。


确认肿瘤起源通常是病理学中的诊断挑战，并且具有重大的治疗影响。细胞角蛋白 7、雌激素受体和 GATA 结合蛋白 3 (GATA3) 是公认的诊断标记物，经常用于支持肿瘤的乳腺起源。然而，它们的特殊性仍有改进的空间。许多非乳腺肿瘤表达细胞角蛋白 7 和雌激素受体，尿路上皮肿瘤经常表达 GATA3。实际需要一种灵敏且特异的新乳腺谱系标记物。 Wnt 家族成员蛋白通过 β-连环蛋白依赖性和独立途径在胚胎发育、组织稳态和肿瘤发育中发挥关键作用。目前的研究评估了 163 例原发性乳腺癌、63 例转移性乳腺癌和 525 例非乳腺上皮肿瘤中 Wnt9b 和 GATA3 的表达。原发性乳腺癌中Wnt9b和GATA3的阳性率均为98.7%。 Wnt9b在转移性乳腺癌中的阳性率为87.3%，GATA3的阳性率为96.8%。对于非乳腺肿瘤，包括 64 例尿路上皮癌，除唾液腺癌外，Wnt9b 均为阴性。研究表明，Wnt9b 是一种乳腺癌标志物，其敏感性与 GATA3 相似，但特异性高于 GATA3，最终可能成为常规外科病理学实践中有用的诊断工具。