PLK1在乳腺癌分子亚型中的表达及其与基底细胞样型乳腺癌的关系

Expression of PLK1 in molecular subtypes of breast carcinoma and its relationship with basal-like breast carcinoma

目的:探讨乳腺癌各分子亚型中PLK1的表达及其与基底细胞样型乳腺癌的关系。方法:回顾性分析803例乳腺浸润性导管癌的临床病理资料,按照Nielsen标准将乳腺浸润性导管癌分成腺腔A型、腺腔B型、HER-2过表达型、基底细胞样型和普通乳腺样型。检测PLK1在5种不同乳腺癌亚型中的表达水平并分析其与基底细胞样型乳腺癌的关系。结果:PLK1在基底细胞样型、普通乳腺样型、HER-2过表达型、腺腔A型及腺腔B型乳腺癌中的阳性表达率分别为58.94%(56/95),39.39%(65/165),33.33%(22/66),17.91%(79/441)及5.56%(2/36)。PLK1在ER阴性的乳腺癌分子亚型中的表达显著高于其在ER阳性的乳腺癌分子亚型中的表达,差异具有统计学意义(P<0.05);PLK1的表达与ER呈负相关,与Ki-67表达呈正相关(P<0.01),与HER-2无显著相关性。ER阴性乳腺癌中,PLK1在基底细胞样型乳腺癌中的阳性表达率最高,显著高于其在HER-2过表达型及普通乳腺样型乳腺癌中的表达,差异有统计学意义(P<0.05)。而HER-2过表达型与普通乳腺样型中相比,PLK1的表达差异无统计学意义(P=0.390)。PLK1的表达与基底细胞样型乳腺癌的淋巴结转移及临床分期相关,而与肿瘤大小及患者年龄无关。结论:PLK1过表达可能与ER阴性的基底细胞样型乳腺癌关系更密切,并在基底细胞样型乳腺的浸润、转移中起重要作用。

Objective： To explore the expression of PLK1 in the molecular subtypes of breast carcinoma and their relationship with basal-like breast carcinoma. Methods： A total of 803 cases of invasive ductal breast carcinoma were identified, the patients were subclassified in Luminal A, Luminal B, HER-2 over-expressing, basal-like and normal breast-like subtypes according to Nielsen criteria. The expression of PLK1 in five subtypes of invasive ductal breast carcinoma and the relationship between the expression of PLK1 and the clinicopathologic features of basal-like breast cancer were detected by immunohistochemistry. Results： Positive expression rate of PLK1 in basal-like, normal breast-like, HER-2 overexpressing, Luminal A, Luminal B subtypes was 58.94%（56/95）, 39.39%（65/165）, 33.33%（22/66）, 17.91%（79/441） and 5.56%（2/36）, respectively. The positive expression rate of PLK1 in ER-negative breast carcinomas（basal-like, normal breast-like and HER-2 over-expressing subtype） was significantly higher than that in ER-positive subtypes（luminal A and lumina B）（P〈0.05）. The expression of PLK1 was negatively correlated with ER and positively correlated with Ki-67（P〈0.01）, while there was no significant correlation with the expression of PLK1 and HER-2. In cases of ER negative breast cancer, the expression of PLK1 in basal-like breast subtype was much higher than that in normal breast-like and HER-2 overexpressing subtype. The expression of PLK1 was correlated with lymph node metastasis and p TNM stage（P〈0.05） of basal-like breast cancer. Conclusion： The overexpression of PLK1 may be closely correlated with ER-negative breast cancer, especially with basal-like breast cancer, and PLK1 may play an important role in the invasion and metastasis of basal-like breast carcinoma.