Curcumin modulates motility of oral cells: a new chemopreventive strategy

There is no current cure for oral/head and neck cancers and even surgical removal of early lesions does not prevent disease progression. Chemoprevention is aimed at inhibiting and/or reversing the carcinogenic process through drug or dietary intervention. Curcumin, a spice extracted from turmeric, has chemopreventive activity. This study examines curcumin's effect on motility within the context of developing new chemopreventive strategies. Objectives: We hypothesize that curcumin inhibits motility and proliferation in oral epithelial cells. We focus on motility within the context of it being a new chemopreventive target, and our aim is to generate novel data to support this direction. Methods: Motility will be monitored using a scratch motility assay, which measures migration distance over time. Proliferation will be monitored by determining a bromodeoxyuridine (BUDR) labeling index. Human premalignant oral epithelial cells (MSK Leuk1 and MSK Leuk1-PEYFP) were seeded on dishes to produce confluent droplets. A streak was made through the center of the cell droplet. Cells were incubated overnight at 37°C in 0 (control), 1μM, 5μM, 10μM, and 20μM curcumin-containing media. Streaks were photographed pre- and post treatment, and the width of the streak was measured (scratch motility assay). Proliferation was determined using immunofluorescent techniques following BUDR labeling. Results: Curcumin was shown to inhibit motility with a dose-response relationship (0, 1μM, 5μM, 10μM, and 20μM). Proliferation, as measured by BUDR incorporation (labeling index), was unaffected by curcumin. Conclusion: Curcumin inhibited motility in a dose-dependent manner with no effect on proliferation. Results from the scratch assay are dependent solely on motility parameters. Progression of a premalignant lesion involves expansion of the lesion over time and lesion expansion may involve both proliferation and motility. Chemopreventive targeting of motility may be a novel strategy to control progression (lesion expansion) over time. Supported by Dean's Student Research Award and NIH-NIDCR Grant R01-14395.