CD44s and CD44v6 Are Predominantly Expressed in the Non-germinal Center B-Cell-like Type of Diffuse Large B-Cell Lymphomas

Abstract

Background: CD44 protein is known as a homing cellular adhesion molecule that is linked to diverse cellular functions such as adhesion, migration and invasion, which are all important in cancer progression and metastasis. The expression of CD44 standard and variant isoforms (CD44 standard isoform [CD44s] and CD44 splice variants containing exon v6 [CD44v6], respectively) is associated with an unfavorable clinical outcome in various neoplasms. Methods: Forty patients who were diagnosed with diffuse large B-cell lymphoma (DLBCL) through biopsy at Hanyang University Hospital between 1996 and 2003 were included in this study. CD44 proteins expression was analyzed by immunohistochemical staining on a tissue microarray and the correlation of CD44 with the types of DLBCL and clinical parameters, including the factors defined by the International Prognostic Index, was evaluated. Results: A high CD44s and intermediate to strong CD44v6 expression, including cytoplasmic membranous staining patterns, was present in 35% (14/40) and 25% (10/40) of DLBCL patients, respectively. High CD44s expression was correlated significantly with non-germinal center B-cell-like types (non-GCB, p = 0.004) and patients with old age (p = 0.041). Conclusions: High CD44s expression may be significantly associated with the non-GCB type compared to the GCB type and may be essential to the prediction of disease outcome in tumor stage III in DLBCL patients.