Abstract: Objective: To detect the expression of TOX and Notch1 protein in for mycosis fungoides (MF) and to determine the role as a potential molecular markers for MF．Methods: TOX and Notch1 protein were detected by immunohistochemical staining in the lesions of 35 patients with MF (15 patients at patch stage, 10 at plaque stage and 10 at tumour stage) and in 45 controls (15 patients with lymphomatoid papulosis, 15 with lichen planus and 15 with psoriasis). Result: The positivity rate of TOX in the patients with MF was 94.3％ and 76％ in controls. The level of TOX protein expression was higher in MF patients than in controls (P<0.05). Notch1 protein was negative in tumor cells of all MF patients and controls. Conclusion: Although TOX expression level was higher in MF patients, TOX protein can not be used as a potential molecular marker for MF and further experimental studies should be performed. Notch1 protein is not a molecular marker for MF.

Key words: cutaneous T-cell lymphomas, MF, TOX, Notch signaling pathways, Notch1