The Tooth Dental Clinic, Kalinga Institute of Dental Sciences KIIT Deemed to be University, Bhubaneswar, Odisha, India.
Department of Dentistry, Nalanda Medical College Hospital, Patna, Bihar, India.
J Cancer Res Ther. 2022 Jul-Sep;18(4):997-1002. doi: 10.4103/jcrt.JCRT_10_20.
The aim and objective of the study were to evaluate the immunohistochemical expression of proliferative markers, Ki67, and MCM2 in oral epithelial dysplasia (OED) and oral squamous cell carcinoma (OSCC), to compare the relationship of their staining patterns, and to look for correlation between them, if any.
Thirty archival paraffin-embedded tissue blocks of previously diagnosed cases of OED, OSCC each, and 10 normal oral mucosa were used in the study. Immunohistochemical staining for MCM2 and Ki67 markers was done and the slides were individually evaluated for MCM2 and Ki67 expression, with immunopositivity determined on the basis of dark brown staining of the nucleus. The number of positively stained nuclei was counted in 10 representative areas and the data were charted and statistically analyzed.
The overall mean expression of both the proteins increased progressively from normal mucosa to OED to OSCC. In normal mucosa, all positively stained nuclei were seen in the basal compartment of the epithelium, while in dysplastic cases, expression was seen toward the surface of squamous epithelium. In OSCC, the frequency of expression of MCM2 and Ki-67 proteins showed an inverse correlation with the degree of tumor differentiation. In well-differentiated cases, the positivity of either marker was restricted to the outermost layer of the tumor cells. In moderately differentiated cases, an expression of Ki-67 was more diffuse in inner layers, whereas the MCM2 antigen was found to be more intense and diffuse in both the inner and outer layers. Whereas in poorly differentiated SCC, positive expression was seen in most of the tumor cells, the mean expression of MCM2 was found to be higher than that of Ki67 in all cases.
MCM2, as a proliferation marker, is superior to Ki67 as it indicates the capacity of proliferation and the ability of DNA replication of a cell.
本研究旨在评估增殖标志物 Ki67 和 MCM2 在口腔上皮异型增生（OED）和口腔鳞状细胞癌（OSCC）中的免疫组织化学表达，比较它们染色模式的关系，并寻找它们之间的相关性（如果有的话）。
本研究使用了 30 个先前诊断为 OED、OSCC 以及 10 个正常口腔黏膜的存档石蜡包埋组织块。进行了 MCM2 和 Ki67 标志物的免疫组织化学染色，根据细胞核的深棕色染色来确定免疫阳性，并对 MCM2 和 Ki67 表达进行单独评估。在 10 个有代表性的区域中计数阳性染色核的数量，并绘制数据图表进行统计分析。
两种蛋白的总体平均表达均从正常黏膜到 OED 再到 OSCC 呈递增趋势。在正常黏膜中，所有阳性染色核均位于上皮的基底细胞层，而在异型增生病例中，表达可见于鳞状上皮的表面。在 OSCC 中，MCM2 和 Ki-67 蛋白的表达频率与肿瘤分化程度呈反比。在分化良好的病例中，任一标志物的阳性表达仅限于肿瘤细胞的最外层。在中度分化的病例中，Ki-67 的表达更为弥漫，而 MCM2 抗原在内层和外层均更为强烈和弥漫。而在低分化 SCC 中，大多数肿瘤细胞均可见阳性表达，所有病例中 MCM2 的平均表达均高于 Ki67。
作为增殖标志物，MCM2 优于 Ki67，因为它可以指示细胞的增殖能力和 DNA 复制能力。
