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

Abstract

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.

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

“…No statistically significant difference was found between participants with no/1–5 teeth removed at baseline versus at 12 months (48.9% vs. 45.5%, p = 0.180). There was no statistically significant difference between the proportions of participants with no/mild alcohol consumption at baseline versus at 12 months according to previously published criteria [ 23 ] for alcohol consumption (18.2% vs. 15.9%, p = 0.625). We recently found an inverse association between CD44 levels and green salad/vegetable intake [ 23 ].…”

“…There was no statistically significant difference between the proportions of participants with no/mild alcohol consumption at baseline versus at 12 months according to previously published criteria [ 23 ] for alcohol consumption (18.2% vs. 15.9%, p = 0.625). We recently found an inverse association between CD44 levels and green salad/vegetable intake [ 23 ]. Here, no statistically significant difference was found between baseline and 12-month values for the proportions of participants consuming less than one or zero salads per week (39.8% vs. 38.6%, p = 0.705), consumption of other vegetables less than once per week (5.7% vs. 6.8%, p = 1.000), consuming green salad or other vegetables less than once per week or never (2.3% vs. 4.5%, p = 0.500), and consuming green salad and other vegetables less once per week or never (66.7% vs. 33.3%, p = 0.508).…”

Relationship Between Dietary Fiber and Vitamin C Intake and Oral Cancer

“…Smoking, alcohol consumption, poor dental hygiene, the human papillomavirus, and betel nut consumption are most commonly reported risk factors of oral cancer ( 6 – 12 ). However, in addition to the conventional risk factors described above, other environmental factors including dietary and nutrients have also been reported in recent research ( 13 – 15 ). The significance of vegetables and fruits abundant in dietary fiber and vitamins in carcinogenesis is garnering more attention among dietary factors ( 16 , 17 ).…”

The Risk of Oral Cancer and the High Consumption of Thermally Processed Meat Containing Mutagenic and Carcinogenic Compounds

“…Some vegetables, e.g., lettuce, broccoli, cabbage, onion, and garlic, can effectively protect against cancer of the mouth, throat, esophagus, and stomach [55]. The studies by Bradford-Bella et al have shown that eating vegetables and green salad at least once a week reduces the concentration of an oral cancer marker (CD44) in saliva and improves the prognosis of oncological patients [56]. These reports are consistent with the results of this study, indicating the protective role of vegetable consumption in the development of oral cancer.…”