Immunohistochemical Expression of Differentiated Embryonic Chondrocyte 1 and Cluster of Differentiation 44 in Oral Potentially Malignant Disorders

Abstract

Background and Objectives: Oral cancer remains a critical global health concern, with oral squamous cell carcinoma (OSCC) being the most prevalent form. Oral potentially malignant disorders (OPMDs), such as oral leukoplakia (OLK), oral lichen planus (OLP), and actinic cheilitis (AC), often precede OSCC. Identifying reliable biomarkers is vital for assessing malignant transformation risk. The present study aimed to evaluate the immunohistochemical expression of differentiated embryonic chondrocyte 1 (DEC1), a marker of dysplasia severity, and cluster of differentiation 44 (CD44), which is associated with cancer progression, in OPMD and OSCC tissues. Materials and Methods: A retrospective analysis was conducted on 145 biopsy specimens from January 2015 to January 2023, comprising normal mucosa (NM), OLK, OLP, AC, and OSCC. DEC1 and CD44 expression levels were assessed using immunohistochemical staining. Positivity scores were determined based on staining intensity and extent, with statistical analyses performed using SPSS software (SPSS Inc., Chicago, IL, USA, version 29.0 for Windows). Results: It was found that CD44 expression significantly increased across OPMD and OSCC compared to NM (p < 0.001). Conversely, DEC1 expression was consistent across lesion types and dysplasia levels. CD44 expression was the highest in AC and OSCC, underscoring its potential role as a progression marker. Conclusions: The results indicate that CD44 is a more sensitive marker for assessing dysplastic severity and malignant transformation, while DEC1 may serve as a complementary marker for early-stage evaluation. Further research involving larger cohorts is needed to confirm these findings.

Keywords: CD44; DEC1; actinic cheilitis; oral leukoplakia; oral lichen planus; oral squamous cell carcinoma.

Figure 1

The positive control of reaction for DEC1 and CD44. (a) Control tissue, HE, ×40; (b) control tissue, uniform membrane expression (Ab. anti-CD44), ×40; (c) control tissue, HE, ×40; (d) control tissue, chondrocyte nuclear expression (Ab. anti-DEC1), ×100; (e) control tissue, HE, ×40; (f) control tissue, nuclear expression of acini and ducts (Ab. anti-DEC1), ×100.

Figure 2

The characteristics of the study specimens.

Figure 3

Immunohistochemical analysis of OPMD. (a) Leukoplakia with low dysplasia, affecting one-thirds of thickness of epithelium (lower part of epithelium, center, and down), associated with lympho-plasmacytic inflammatory infiltrate in band, HE, ×40. (b) Leukoplakia—nuclear expression, in significant number of cells, high intensity (Ab. anti-DEC1), ×100. (c) Leukoplakia—membrane expression with strong staining intensity in one-thirds of lower part of mucosa in 20% of cells (Ab. anti-CD44), ×100. (d) Oral lichen planus without dysplasia, HE, ×40. (e) Oral lichen planus–nuclear expression with moderate staining intensity in 90% of cells (Ab. anti-DEC1), ×40. (f) Oral lichen planus—membrane expression with high intensity in 40% of cells in lower part of mucosa (Ab. anti-CD44), ×40. (g) Actinic cheilitis with moderate dysplasia, HE, ×40. (h) Actinic cheilitis—increased cell count, high nuclear staining intensity and diffuse in all mucosa (Ab. anti-DEC1), ×100. (i) Actinic cheilitis—high, diffuse membranous staining in all layers of mucosa (Ab. anti-CD44), ×40.

Figure 4

Immunohistochemical analysis of NM, OLK, and OSCC. (a) Normal mucosa, HE, ×40; (b) normal mucosa—absent expression (Ab. anti-DEC1), ×40; (c) normal mucosa—low cell count, weak staining intensity, in lower part of mucosa, in basal layer (Ab. anti-CD44), ×40; (d) leukoplakia without dysplasia, HE, ×40; (e) leukoplakia—nuclear expression, in 40% of cells, moderate intensity, upper right (Ab. anti-DEC1), ×40; (f) leukoplakia—membrane expression with strong staining intensity in 60% of cells (Ab. anti-CD44), ×40; (g) moderate differentiated, ulcerated, infiltrative OSCC with keratin pearls, HE, ×40; (h) well-differentiated OSCC—nuclear expression, diffuse, most cells, weak intensity (Ab. anti-DEC1), ×40; (i) well-differentiated OSCC—membrane expression, increased cell number, strong intensity (Ab. anti-CD44), ×40.