Department of Oral Maxillofacial Surgery and Diagnostic Sciences, University of Florida, College of Dentistry, FL, USA.
Cancer Biol Ther. 2010 Oct 1;10(7):694-9. doi: 10.4161/cbt.10.7.12895.
Oral squamous cell carcinoma (OSCC) is the most prevalent malignancy of the oral cavity resulting in severe morbidity and mortality. To date only few proteins have been suggested as potential biomarkers or targets for this type of cancer. Cancerous inhibitor of PP2A (CIP2A) is a protein expressed in epithelial tissues that stabilizes the oncogene c-Myc and causes cell transformation. This study was designed to investigate the expression of CIP2A in OSCC cell lines and tissues representing human normal, dysplasia and OSCC.
Using quantitative real time PCR, mRNA quantification for CIP2A was performed in a primary gingival cell line and OSCCs CAL 27 and SCC-25. Paraffin embedded human specimen classified as normal, dysplastic or OSCC were immunohistochemically stained for CIP2A expression. EGFR and CIP2A were also stained by immunofluorescence for co-localization. Samples of human normal oral tissue and OSCC were studied by PCR for mRNA expression of CIP2A.
CIP2A was significantly increased in the human carcinoma cell lines compared to the primary gingival cell line. CIP2A was overexpressed in the human oral dysplasia and OSCC tissues compared to normal oral tissues. CIP2A was also preferentially localized in the dysplastic and OSCC epithelial areas compared to EGFR that was expressed mainly in areas of relatively normal epithelium and in dysplastic tissues above the basal layers.
CIP2A may play a significant role in oral malignant transformation and therefore, it may be a potential target for chemotherapy of OSCC.
口腔鳞状细胞癌（OSCC）是口腔最常见的恶性肿瘤，导致严重的发病率和死亡率。迄今为止，只有少数几种蛋白质被认为是这种癌症的潜在生物标志物或靶点。蛋白磷酸酶 2A 的致癌抑制剂（CIP2A）是一种在上皮组织中表达的蛋白质，它稳定致癌基因 c-Myc 并导致细胞转化。本研究旨在研究 CIP2A 在代表人类正常、发育不良和 OSCC 的 OSCC 细胞系和组织中的表达。
使用定量实时 PCR，在原代牙龈细胞系和 OSCC 细胞 CAL 27 和 SCC-25 中进行 CIP2A 的 mRNA 定量。对石蜡包埋的人类标本进行 CIP2A 表达的免疫组织化学染色，这些标本分为正常、发育不良或 OSCC。还通过免疫荧光对 EGFR 和 CIP2A 进行共定位染色。通过 PCR 研究人正常口腔组织和 OSCC 样本中 CIP2A 的 mRNA 表达。
与原代牙龈细胞系相比，CIP2A 在人类癌细胞系中显著增加。与正常口腔组织相比，CIP2A 在人类口腔发育不良和 OSCC 组织中过度表达。与主要在相对正常上皮区域和发育不良组织的基底层以上表达的 EGFR 相比，CIP2A 也优先定位于发育不良和 OSCC 上皮区域。
CIP2A 可能在口腔恶性转化中发挥重要作用，因此，它可能是 OSCC 化疗的潜在靶点。
