Department of Periodontology and Oral Medicine, School of Dental Medicine, University of Belgrade, Belgrade, Serbia.
J BUON. 2020 Mar-Apr;25(2):1193-1198.
Oral lichen planus (OLP), is considered premalignant condition. This study tried to investigate the possibility of malignant transformation in OLP patients, by measuring the level of tumor suppressor protein p16INK4A, which is a product of the cyclin-dependent kinase inhibitor 2 (CDK2). CDK inhibitors may be responsible for maintenance of cell cycle. An imbalance in the cell cycle regulatory pathway involving p16/pRb may lead to unrestricted proliferation and tumorigenesis.
40 patients with OLP underwent biopsy. Two control groups were included in this research, 13 healthy persons and 12 patients with oral squamous cell carcinoma (OSCC). All tissue samples were treated immunohistochemically using avidin-biotin peroxidase complex method.
The number of patients with p16 positive cells was significantly higher in OLP (72.5%) in comparison to OSCC (33.33%). Although the prevalence of patients with p16 positive cells in OSCC was low, they expressed the highest percentage of p16 positive keratinocytes. Staining intensity of cytoplasm was also higher in p16 positive keratinocytes of OSCC in comparison to OLP.
These results suggest that inactivation of p16 is an early detectable event in oral tumorigenesis. P16 expression could also be connected with tumor grading and may be useful marker in oral tumor progression.
口腔扁平苔藓（OLP）被认为是癌前病变。本研究试图通过测量肿瘤抑制蛋白 p16INK4A 的水平来探讨 OLP 患者发生恶性转化的可能性，p16INK4A 是细胞周期蛋白依赖性激酶抑制剂 2（CDK2）的产物。CDK 抑制剂可能负责维持细胞周期。涉及 p16/pRb 的细胞周期调控途径失衡可能导致不受限制的增殖和肿瘤发生。
40 例 OLP 患者接受活检。本研究纳入了两个对照组，包括 13 名健康人和 12 名口腔鳞状细胞癌（OSCC）患者。所有组织样本均采用亲和素-生物素过氧化物酶复合物法进行免疫组织化学处理。
与 OSCC（33.33%）相比，OLP 患者中 p16 阳性细胞数明显更高（72.5%）。尽管 OSCC 中 p16 阳性细胞的患病率较低，但它们表达的 p16 阳性角质形成细胞百分比最高。与 OLP 相比，OSCC 中 p16 阳性角质形成细胞的细胞质染色强度也更高。
这些结果表明，p16 的失活是口腔肿瘤发生中早期可检测到的事件。p16 的表达也可能与肿瘤分级有关，并且可能是口腔肿瘤进展的有用标志物。
