Decreased Levels of Soluble CD44 in a High-Risk Population following a Smoking Cessation Program

Tobacco is a risk factor of head and neck cancer (HNC) and smoking cessation alone may reduce HNC risk by 70%. Soluble CD44 (solCD44), a cell surface receptor linked to cell proliferation and migration, and total protein (TP) levels can detect early HNC. This study aims to determine whether salivary solCD44 and TP levels in oral rinses change following a smoking cessation program. 150 smokers provided oral rinse samples at baseline and at a 12-month follow-up after participation in a smoking cessation program. Assays to measure levels of solCD44, TP, and cotinine, a metabolite used as a biomarker of tobacco exposure, were completed. A paired-samples t-test was used to determine whether there was a statistically significant (p < 0.05) mean difference in biomarker levels before and after the program. Baseline and at 12-month follow-up data were available for 88 subjects, 21 of whom quit smoking entirely. Mean levels of solCD44 significantly decreased by 0.412 ng/mL from baseline to the 12-month follow-up, p = 0.010. There was no significant difference in mean TP levels, p = 0.975. Mean cotinine levels decreased significantly by 74.7 ng/mL, p = 0.035. This is the first work demonstrating an association between smoking cessation and decreased solCD44 levels in oral rinses. Decreased expression of the tumorigenic CD44 may be one mechanism by which smoking cessation lowers cancer risk.

Green Salad Intake Is Associated with Improved Oral Cancer Survival and Lower Soluble CD44 Levels

Deficiencies in fruit and vegetable intake have been associated with oral cancer (oral cavity and oropharyngeal). Salivary rinses contain measurable biomarkers including soluble CD44 (solCD44) and total protein, which are known markers of oral cancer risk. This study investigates the effect of nutritional factors on solCD44 and protein levels to evaluate oral cancer risk and survival. We evaluated solCD44 and protein levels from 150 patients with oral and oropharyngeal squamous cell carcinoma and 150 frequency-matched controls. We subsequently characterized the effect of food group consumption and these biomarkers on progression-free survival (PFS) and overall survival (OS). Patients reported eating fewer servings of salad (p = 0.015), while controls reported eating fewer servings of potatoes (p < 0.001). Oral cancer patients who consumed at least one serving per week of green salad were found to have significantly lower CD44 levels than those who ate salad less frequently (mean of log2[solCD44]1.73 versus 2.25, p = 0.014). Patients who consumed at least one serving per week of “salad or other vegetables” had significantly longer PFS (median 43.5 versus 9.1 months, p = 0.003, adjusted hazard ratio (HR) = 0.39 p = 0.014) and OS (median 83.6 versus 10 months, p = 0.008, adjusted HR = 0.04 p = 0.029). These findings suggest that dietary factors, namely greater green salad and vegetable intake, may be associated with lower CD44 levels and better prognosis in oral cancer patients.

Determination of soluble CD44 in serum by using a label-free aptamer based electrochemical impedance biosensor

A label-free aptamer-based electrochemical impedance biosensor was developed for convenient and rapid detection of serum tumor biomarker CD44.

Diagnostic and prognostic value of cancer stem cell marker CD44 and soluble CD44 in the peripheral Blood of patients with oral Squamous cell carcinoma

BackgroundHead and neck cancer is a major health problem. Recent studies on the pathobiology of oral squamous cell carcinoma (OSCC) have led to the discovery of a small population of cancer cells with a consistent behavior with the features of cancer stem cells (CSCs). CSCs are required and responsible for initiation, maintenance and recurrence of disease. Molecular markers are commonly used for the identification of CSCs. CD44 is the most reported CSC marker in OSCC.The aim of the study was to evaluate and correlate the expression of CD44 in different histopathological grades of OSCC, as well as to assess the diagnostic and prognostic value of soluble CD44 (CD44sol) in peripheral blood of patients.Materials and methodsFifteen patients with OSCC were included; biopsies were histologically evaluated using haematoxylin and eosin. Serial sections were immunohistochemically stained by monoclonal antibody to CD44. The intensity of immunostaining of CD44 was calculated. Enzyme-linked immunosorbent assay (ELISA) method was used to determine the concentration of CD44sol in the blood serum.ResultsAll grades of OSCC showed membranous immunosignaling of CD44. The well, moderately and poorly differentiated OSCC cases showed weak, moderate and intense positive membranous immunosignaling of CD44 respectively.CD44sol levels were significantly higher in OSCC patients than they were in control groups. Soluble CD44 serum levels were significantly higher in poorly differentiated than they were in moderately and well differentiated.ConclusionCSCs detection in fixed human tissue and CD44sol detection in peripheral blood using ELISA seemed to be a promising method and may have a diagnostic and prognostic value in management of OSCC.