Squarize Cristiane Helena, Castilho Rogério Moraes, Santos Pinto Décio
Department of Oral Pathology, School of Dentistry, University of São Paulo, Sao Paulo, 05508-900, Brazil.
J Oral Pathol Med. 2002 Aug;31(7):379-84. doi: 10.1034/j.1600-0714.2002.00142.x.
PTEN is a tumor suppressor gene that encodes a dual phosphatase protein capable of modulating membrane receptors and interaction of the cell and extracellular stimuli. PTEN regulates cell physiology such as division, differentiation/apoptosis and also migration and adhesion. The expression of PTEN was evaluated by immunohistochemistry in OSCC and compared to a well-established histological malignancy grading system. The well-differentiated OSCC were 59.1% and poorly differentiated were 40.9%. According to PTEN expression, the cases were 45.5% positive (the entire tumor showed stained), 22.7% mixed (both negative and positive cells were present) and 31.8% negative (no staining was seen in the tumor cells). PTEN expression in OSCC was related to the malignancy grade (P < 0.0005). Aggressive tumors with a high score of malignancy did not express PTEN, and clearly, the PTEN expression was present in the epithelium adjacent to the tumor. Negative cells were in the invasion border of the tumor. This result suggests that PTEN is related to histologic pattern and biological behavior of OSCC and may be a used as a prognostic marker in the future. The role of PTEN during carcinogenesis and as a biomarker should be further investigated.
PTEN是一种肿瘤抑制基因，它编码一种双磷酸酶蛋白，能够调节膜受体以及细胞与细胞外刺激的相互作用。PTEN调节细胞生理过程，如分裂、分化/凋亡，以及迁移和黏附。通过免疫组织化学方法评估PTEN在口腔鳞状细胞癌（OSCC）中的表达，并与成熟的组织学恶性分级系统进行比较。高分化OSCC占59.1%，低分化占40.9%。根据PTEN表达情况，病例中45.5%为阳性（整个肿瘤均有染色），22.7%为混合性（同时存在阴性和阳性细胞），31.8%为阴性（肿瘤细胞未见染色）。OSCC中PTEN的表达与恶性程度相关（P < 0.0005）。恶性程度高的侵袭性肿瘤不表达PTEN，显然，PTEN表达存在于肿瘤相邻的上皮中。阴性细胞位于肿瘤的侵袭边界。这一结果表明，PTEN与OSCC的组织学模式和生物学行为相关，未来可能用作预后标志物。PTEN在致癌过程中的作用以及作为生物标志物的作用应进一步研究。
