Expressions of OCT-4 and CD44 in laryngeal squamous cell carcinoma and the clinicopathological significance of OCT-4 and CD44 double positive

Abstract

Objective To detect the expression of nuclear transcription factor OCT-4 in laryngeal squamous cell carcinoma (LSCC) and its relationship with CD44, and to explore the relationship between OCT-4 and the cancer stem cells and its significance in tumors. Methods Sixty-nine specimens of laryngeal surgical resection were selected from LSCC patients from January 2008 to December 2012 in Lanzhou General Hospital of Lanzhou Military Region. Another 18 cases of normal laryngeal mucosa tissues were selected as control. OCT-4, CD44 and OCT-4+ CD44+ cells were observed by using tissue microarray, immunohistochemistry staining and immunohistochemical double staining techniques, and the relationship between their pathological features, such as expression intensity, distribution, cell morphology and clinical parameters were analyzed to explore the clinicopathological significance of CD44+ OCT-4+ cells. Results The percentage of CD44-positive cells in LSCC was significantly higher than that in normal laryngeal mucosa tissues [(63.62±8.76)% vs. (13.61±5.81)%, P < 0.001]. The percentage of OCT-4-positive cells in LSCC was (50.44±10.84)%, while it was not expressed in normal laryngeal mucosa tissues (P < 0.001). In LSCC, the expression of OCT-4 was significantly lower than that of CD44 (P < 0.001); the coexpression rate of these two molecules was (5.07±2.90)%. The percentage of CD44-positive cells in poorly differentiated LSCC was significantly higher than that in the well-differentiated group [62.78% (8.22%) vs. 28.62% (30.45%), P < 0.05]. The percentage of OCT-4-positive cells in poorly differentiated LSCC was significantly higher than that in the well-differentiated group [49.89% (13.12%) vs. 33.00% (20.00%), P < 0.05]. In the cancer stem cells, the percentage of OCT-4+ CD44+ cells in poorly differentiated carcinoma group was also significantly higher than that in the well-differentiated carcinoma group (P < 0.01), the lower the degree of differentiation, the higher the expression level of OCT-4. In LSCC poorly differentiated group, the expressions of OCT-4 and CD44 showed no significant difference between different T stages, but the percentage of OCT-4+ CD44+ cells elevated with T stage increasing (P < 0.05). The expression of OCT-4 in patients with lymph node metastasis was significantly higher than that in patients without lymph node metastasis (P < 0.01). Conclusions The expressions of OCT-4 and CD44 are associated with the malignant biological behaviors of LSCC closely. OCT-4 may be a valuable marker of tumor stem cells of LSCC. Key words: Laryngeal neoplasms; Carcinoma, squamous cell; OCT-4; CD44; Neoplastic stem cells