Kitkhajornkiat Athip, Rungsiyanont Sorasun, Talungchit Sineepat, Jirawechwongsakul Pimporn, Taebunpakul Patrayu
Department of Oral Surgery and Oral Medicine, Faculty of Dentistry, Srinakharinwirot University, Bangkok, Thailand.
J Oral Biol Craniofac Res. 2020 Jul-Sep;10(3):281-286. doi: 10.1016/j.jobcr.2020.06.003. Epub 2020 Jun 16.
Malignant transformation of oral lichen planus (OLP) was reported particularly in erosive type, however, it remains inconclusive. Cathepsin L was shown to promote tumor growth and invasion in many cancers. Therefore, cathepsin L expression in erosive and non-erosive OLP compared with oral epithelial dysplasia and oral squamous cell carcinoma (OSCC) were investigated.
Thirty specimens of OLP (15 cases each of erosive and non-erosive OLP), 10 cases of oral epithelial dysplasia and 10 cases of OSCC were included. Ten healthy gingiva specimens were served as controls. All specimens were stained with cathepsin L antibody using immunohistochemistry technique.
Cathepsin L was expressed in all OLP and OSCC cases. In oral epithelial dysplasia and healthy gingiva, the expression was found at 90% and 50% respectively. The percentage of positive cells was the highest in erosive OLP (27.26 ± 12.09%), followed by non-erosive OLP (20.85 ± 7.43%), OSCC (20.15 ± 15.70%), oral epithelial dysplasia (9.24 ± 7.00%) and healthy gingiva (2.27 ± 5.65%). Most of non-erosive OLP cases showed mild staining intensity while erosive OLP and OSCC showed moderate staining intensity. Cathepsin L was mainly expressed at basement membrane zone and inflammatory cells of OLP. In OSCC, the expression was found in tumor islands and keratin pearls. In oral epithelial dysplasia and normal gingiva, cathepsin L expressions were low and presented in scattered pattern in both epithelium and connective tissue.
According to the patterns of expression in this study, cathepsin L could be implicated in pathogenesis and severity of OLP.
口腔扁平苔藓（OLP）的恶性转化尤其在糜烂型中被报道，然而，其仍无定论。组织蛋白酶L在许多癌症中显示出促进肿瘤生长和侵袭的作用。因此，研究了糜烂型和非糜烂型OLP中组织蛋白酶L的表达，并与口腔上皮发育异常和口腔鳞状细胞癌（OSCC）进行比较。
纳入30例OLP标本（糜烂型和非糜烂型OLP各15例）、10例口腔上皮发育异常和10例OSCC。10例健康牙龈标本作为对照。所有标本采用免疫组织化学技术用组织蛋白酶L抗体染色。
组织蛋白酶L在所有OLP和OSCC病例中均有表达。在口腔上皮发育异常和健康牙龈中，表达率分别为90%和50%。阳性细胞百分比在糜烂型OLP中最高（27.26±12.09%），其次是非糜烂型OLP（20.85±7.43%）、OSCC（20.15±15.70%）、口腔上皮发育异常（9.24±7.00%）和健康牙龈（2.27±5.65%）。大多数非糜烂型OLP病例染色强度较轻，而糜烂型OLP和OSCC染色强度中等。组织蛋白酶L主要表达于OLP的基底膜区和炎症细胞。在OSCC中，表达见于肿瘤岛和角化珠。在口腔上皮发育异常和正常牙龈中，组织蛋白酶L表达较低，在上皮和结缔组织中呈散在分布。
根据本研究中的表达模式，组织蛋白酶L可能与OLP的发病机制和严重程度有关。
