RESUMO
BACKGROUND: The purpose of this study was to investigate the potential role of variable microRNA (miRNA) expression in the development of multidrug resistance (MDR) in head and neck cancer. METHODS: Head and neck squamous cell carcinoma cell lines UMSCC-1 and SQ20B were treated with docetaxel at increasing concentrations to develop resistant cell lines. Parental and resistant cells were treated with cisplatin, 5-fluorouracil, paclitaxel, methotrexate, and doxorubicin to confirm cross-resistance. The miRNA pattern of resistant cells was then compared with their parental cells. RESULTS: Docetaxel treatment successfully induced resistance primarily and induced multidrug cross-resistance. Resistant cells showed significant downregulation of miR-100, miR-130a, and miR-197 and upregulation in miR-101, miR-181b, miR-181d, and miR-195 expression when compared with their parent cells (p < .01). Real-time polymerase chain reaction (PCR) analysis confirmed statistically significant downregulation in miR-100 and miR-130a and upregulation in miR-181d expression (p < .001). CONCLUSION: Alterations in miRNA expression has direct relationship to MDR in head and neck cancer and may serve as biomolecular targets for reversal of MDR.
