Suprabasal expression of Ki-67 as a marker for the severity of oral epithelial dysplasia and oral squamous cell carcinoma

Abstract

Background:Transition of the normal oral epithelium to dysplasia and to malignancy is featured by increased cell proliferation. To evaluate the hypothesis of distributional disturbances in proliferating and stem cells in oral epithelial dysplasia and oral squamous cell carcinoma (OSCC).Aim:To evaluate layer wise expression of Ki-67 in oral epithelial dysplasia and in OSCC.Materials and Methods:Thirty histologically confirmed cases of oral epithelial dysplasia, fifteen cases of OSCC and five cases of normal buccal mucosa were immunohistochemically examined and nuclear expression of Ki-67 was counted according to basal, parabasal, and suprabasal layers in epithelial dysplasia and number of positive cells per 100 cells in OSCC as labeling index (LI).Results:Suprabasal expression of Ki-67 increased according to the severity of epithelial dysplasia and the difference was statistically significant (P < 0.001). The mean Ki-67LI was 12.78 for low risk lesions, 28.68 for high risk lesions, 39.45 for OSCC and 13.6 for normal buccal mucosa.Conclusion:The results of the present study demonstrate the use of proliferative marker Ki-67 in assessing the severity of epithelial dysplasia. Suprabasal expression of Ki-67 provides an objective criteria for determining the severity of epithelial dysplasia and histological grading of OSCC.

Inhibition of G9a induces DUSP4-dependent autophagic cell death in head and neck squamous cell carcinoma

“…Interestingly, we also noticed that G9a and Ki-67 present similar distribution patterns, centralized at the basal layer, in the proliferative compartment for normal epithelium [33], but not in other squamous cells in the normal epidermis (Figure 1A and Additional file 5: Figure S4). These findings point to the hypothesis that maintenance of high G9a expression levels may be necessary for both normal basal layer cells and tumor cells to sustain their highly proliferative properties.…”

A study of Ki-67 expression and its clinicopathological determinants in nondysplastic oral leukoplakia

“…On the contrary, Dwivedi et al . [8] noticed very little disagreement between the mean LIs of normal oral epithelium (13.65%) and nondysplastic OL (12.78%). Same was the experience of Kumar et al .…”

“…[8] Its expression proportionately increases with the severity of dysplasia in OL. Therefore, it acts as a useful tool for detection of initial conversion into dysplasia.…”

“…[9] However, the earlier studies emphasizing on the diagnostic/prognostic competency as well as on scoring/labeling indices (LIs) of Ki-67 were mostly attributed to the comparative evaluation through various grades of dysplasia up to squamous cell carcinoma (SCC). [67891011] In this context, the present study aimed at evaluating the Ki-67 expression in the OL cases, which specifically did not feature any evidence of dysplasia on routine histopathology. Furthermore, an attempt was made to correlate various clinicopathological factors with the LI of Ki-67 in these cases.…”

Expression of Bcl-2 and MIB-1 Markers in Oral Squamous Cell Carcinoma (OSCC)- A Comparative Study

“…Abnormal Bcl-2 protein favours cell accumulation in tumour cells by allowing them to escape apoptosis, whereas increased Ki-67 protein promotes abnormal proliferation [17,18]. Detection of proliferative index and apoptotic abnormalities with the use of such markers, even before the consequences become clinically or histologically evident, will greatly enhance the potential for making an early diagnosis [19].…”