Satelur Krishnanand Prakash, Bopaiah Shiny, Bavle Radhika Manoj, Ramachandra Prashant
Professor, Department of Oral Pathology, Krishnadevaraya College of Dental Sciences, Bengaluru, Karnataka, India.
Postgraduate Student, Department of Oral Pathology, Krishnadevaraya College of Dental Sciences, Bengaluru, Karnataka, India.
J Clin Diagn Res. 2017 Aug;11(8):ZC29-ZC32. doi: 10.7860/JCDR/2017/30740.10274. Epub 2017 Aug 1.
Malignant transformation of Oral Lichen Planus (OLP) remains a much discussed but very less understood realm. Various hypotheses and theories have been put forward to explain the same. Malignant transformation is a complex interplay of epithelial mesenchymal factors acting in tandem. This study tries to identify and asses the stromal changes that pave the way for epithelial migration using Cathepsin B (CB) a cysteine protease belonging to the Cathepsin family. Various studies have been done to study its role in human cancers which have proven that CB helps mark and identify tissue digestion.
The purpose of this study was to evaluate the expression of CB, in OLP and examine its possible role in malignant transformation.
Immunohistochemical analysis of CB expression was done in 50 OLP tissues along with 10 normal mucosa tissue and 10 Oral Squamous Cell Carcinoma (OSCC) cases (control groups). Evaluation was done on the basis of intensity of staining. The intensity was graded in all the cases by assigning values of 0 to 4 in ascending order. Two other observers evaluated the staining and intensity independently and the average of the observations was taken.
A variable staining pattern in both the stroma and the cytoplasm of the epithelial cells was noticed. The staining intensity was clearly increased in OLP tissues when compared to normal control tissue and OSCC which served as our positive control. The staining patterns in tissues of OLP and OSCC to Cathepsin B were similar. The staining intensity of Cathepsin B was observed to be increased in both these groups of tissues.
This study demonstrated a significantly increased expression of CB in OLP. This may be correlated to a possible indicator for its eventual malignant transformation. This overexpression of CB amounts to an array of stromal changes that take place and different mechanisms that get activated underneath the epithelium leading to the formation of what is known as a tumour microenvironment, a well proven entity. We hypothesize that it is this which felicitates the invasion of the overlying epithelial cells.
口腔扁平苔藓（OLP）的恶性转化仍是一个备受讨论但了解甚少的领域。人们提出了各种假设和理论来解释这一现象。恶性转化是上皮-间充质因子协同作用的复杂过程。本研究试图利用组织蛋白酶B（CB，一种属于组织蛋白酶家族的半胱氨酸蛋白酶）来识别和评估为上皮迁移铺平道路的基质变化。已经开展了多项研究来探讨其在人类癌症中的作用，这些研究证明CB有助于标记和识别组织消化。
本研究的目的是评估CB在OLP中的表达，并研究其在恶性转化中可能发挥的作用。
对50例OLP组织、10例正常黏膜组织和10例口腔鳞状细胞癌（OSCC）病例（对照组）进行CB表达的免疫组织化学分析。根据染色强度进行评估。通过按升序赋予0至4的值对所有病例的强度进行分级。另外两名观察者独立评估染色和强度，并取观察结果的平均值。
在上皮细胞的基质和细胞质中均观察到可变的染色模式。与作为阳性对照的正常对照组织和OSCC相比，OLP组织中的染色强度明显增加。OLP和OSCC组织中组织蛋白酶B的染色模式相似。观察到这两组组织中组织蛋白酶B的染色强度均增加。
本研究表明OLP中CB的表达显著增加。这可能与其最终恶性转化的潜在指标相关。CB的这种过表达相当于一系列发生的基质变化以及上皮下方被激活的不同机制，从而导致形成所谓的肿瘤微环境，这是一个已得到充分证实的实体。我们假设正是这一点促进了上层上皮细胞的侵袭。
