Drosos Yiannis, Kouloukoussa Mirsini, Østvold Anne Carine, Grundt Kirsten, Goutas Nikos, Vlachodimitropoulos Dimitrios, Havaki Sophia, Kollia Panagoula, Kittas Christos, Marinos Evangelos, Aleporou-Marinou Vassiliki
Department of Genetics and Biotechnology, Faculty of Biology, University of Athens, Panepistimioupoli, 15701 Ilissia, Greece.
Cancer Cell Int. 2009 Aug 10;9:19. doi: 10.1186/1475-2867-9-19.
NUCKS (Nuclear, Casein Kinase and Cyclin-dependent Kinase Substrate) is a nuclear, DNA-binding and highly phosphorylated protein. A number of reports show that NUCKS is highly expressed on the level of mRNA in several human cancers, including breast cancer. In this work, NUCKS expression on both RNA and protein levels was studied in breast tissue biopsies consisted of invasive carcinomas, intraductal proliferative lesions, benign epithelial proliferations and fibroadenomas, as well as in primary cultures derived from the above biopsies. Specifically, in order to evaluate the level of NUCKS protein in correlation with the histopathological features of breast disease, immunohistochemistry was employed on paraffin sections of breast biopsies of the above types. In addition, NUCKS expression was studied by means of Reverse Transcription PCR (RT-PCR), real-time PCR (qRT-PCR) and Western immunoblot analyses in the primary cell cultures developed from the same biopsies.
The immunohistochemical Results showed intense NUCKS staining mostly in grade I and II breast carcinomas compared to normal tissues. Furthermore, NUCKS was moderate expressed in benign epithelial proliferations, such as adenosis and sclerosing adenosis, and highly expressed in intraductal lesions, specifically in ductal carcinomas in situ (DCIS). It is worth noting that all the fibroadenoma tissues examined were negative for NUCKS staining. RT-PCR and qRT-PCR showed an increase of NUCKS expression in cells derived from primary cultures of proliferative lesions and cancerous tissues compared to the ones derived from normal breast tissues and fibroadenomas. This increase was also confirmed by Western immunoblot analysis. Although NUCKS is a cell cycle related protein, its expression does not correlate with Ki67 expression, neither in tissue sections nor in primary cell cultures.
The results show overexpression of the NUCKS protein in a number of non malignant breast lesions and cancerous tissues. In particular, the NUCKS overexpression in ADH and DCIS indicates a significant role of this protein in neoplastic progression.
NUCKS（核、酪蛋白激酶和细胞周期蛋白依赖性激酶底物）是一种核内、DNA结合且高度磷酸化的蛋白质。多项报告显示，NUCKS在包括乳腺癌在内的多种人类癌症中，在mRNA水平上高度表达。在本研究中，对由浸润性癌、导管内增殖性病变、良性上皮增殖和纤维腺瘤组成的乳腺组织活检样本，以及从上述活检样本中获得的原代培养物，研究了NUCKS在RNA和蛋白质水平上的表达。具体而言，为了评估NUCKS蛋白水平与乳腺疾病组织病理学特征的相关性，对上述类型乳腺活检样本的石蜡切片进行了免疫组织化学检测。此外，通过逆转录PCR（RT-PCR）、实时PCR（qRT-PCR）和蛋白质免疫印迹分析，研究了从相同活检样本中培养的原代细胞中NUCKS的表达情况。
免疫组织化学结果显示，与正常组织相比，NUCKS染色主要在I级和II级乳腺癌中呈强阳性。此外，NUCKS在良性上皮增殖（如腺病和硬化性腺病）中呈中度表达，在导管内病变中，特别是在原位导管癌（DCIS）中呈高度表达。值得注意的是，所有检测的纤维腺瘤组织NUCKS染色均为阴性。RT-PCR和qRT-PCR显示，与来自正常乳腺组织和纤维腺瘤的细胞相比，增殖性病变和癌组织原代培养细胞中NUCKS表达增加。蛋白质免疫印迹分析也证实了这种增加。尽管NUCKS是一种与细胞周期相关的蛋白质，但其表达在组织切片和原代细胞培养中均与Ki67表达无关。
结果显示NUCKS蛋白在一些非恶性乳腺病变和癌组织中过表达。特别是，NUCKS在非典型导管增生（ADH）和原位导管癌（DCIS）中的过表达表明该蛋白在肿瘤进展中起重要作用。
