胸腺素β10在人类乳腺癌中的表达

Expression of Thymosin β10 (Tβ10) Protein in Human Breast Cancer

目的:探讨胸腺素β10(Thymosinβ10,Tβ10)在人类乳腺癌中的表达及其临床病理意义。方法:采用兔抗人Tβ10多克隆抗体,ABC免疫组织化学方法检测经福尔马林固定、石蜡包埋的10例乳腺增生症、76例原发性乳腺癌及27例淋巴结转移性乳腺癌中Tβ10的表达状况,同时检测两种恶性度、转移潜能以及雌激素受体表达状况均不相同的乳腺癌细胞系中Tβ10蛋白的表达水平;此外,我们还检测了76例原发性乳腺癌临床病例中ER和c-erbB-2的蛋白水平。结果:Tβ10表达定位于胞浆中,10例乳腺增生症组织表达为阴性或仅在肌上皮内有非常微弱的表达。临床乳腺癌病例的阳性率为100%(76/76),但表达强弱有差别:伴早期浸润的原位癌弱于普通浸润癌,二者具有显著性差异(P<0.01);高分化组染色弱于中低分化组(P<0.05);虽然淋巴结转移灶内的染色强于原发癌,但此差异不具有统计学意义。伴/不伴淋巴结转移的组间差异无统计学意义(P>0.05)。在乳腺癌细胞系中,雌激素依赖性、恶性度和转移潜能较低的MCF-7细胞的Tβ10表达弱于雌激素不依赖性、恶性度和转移潜能较高的MDA-MB-231细胞。未发现Tβ10与ER和c-erbB-2的表达具有相关性。结论:虽然乳腺正常的肌上皮细胞中可存在少量Tβ10蛋白,但此蛋白在乳腺组织发生癌变和浸润的过程中会逐渐增高。

Objective: To investigate the clinico-pathological significance of thymosin β10(Tβ10)in human breast cancer. Methods: 113 formalin fixed, paraffin-embedded breast tissue samples, including 10 fibrocystic lesions, 76 primary carcinomas and 27 metastatic carcinomas in axillary lymph nodes, as well as two human breast cancer cell lines (differing in their estrogen receptor expression, histological grade and metastatic potential), were analyzed by immunohistochemical analysis with a specific antibody for Tβ10. ER and c-erbB2 proteins were also examined in all 76 primary breast cancers. Results: Tβ10 was found in all the carcinoma cases and the staining pattern was cytoplasmic, whereas the benign fibrocystic lesions showed very weak staining or did not stain at all. Also, the intensity of staining in the in situ carcinomas with microinvasion was markedly weaker than the infiltrating and metastatic lesions. In both clinical cases and tumor cell lines, the expression of Tβ10 was found to be increased with the rising differentiation grade of carcinomas. Although the staining intensity is stronger in the metastatic lesions compared with the primary carcinomas, there is no statistically significant difference(P>0.05). No correlation was found in Tβ10 expression level with estrogen receptor status or c-erbB2 status. Conclusions: Although minute amounts of Tβ10 are present in fibrocystic lesions, the expression of Tβ10 was found to be markedly increased during malignant transformation and invasion of the human breast cancers. Thus Tβ10 might be one of the new markers for diagnosing and predicting prognosis of the human breast cancers.