Abstract: AIM: To investigate the expression of signal transducers and activators of transcription 3(STAT3),vascular endothelial growth factor(VEGF), CyclinD1 and their correlation in the lesions of lichen planus.METHODS: The expression levels of STAT3,VEGF and CyclinD1 in the 23 cases of lesions of lichen planus were detected by the immunohistochemistry,and 12 cases of normal human tissues were also detected as control group.The expression and their relationship with pathological factors were analyzed.RESULTS: The expression rates of STAT3,VEGF and CyclinD1 in lichen planus were 60.87%(14/23),69.57%(16/23)and 56.52%(13/23),the expression rates of STAT3,VEGF and CyclinD1 in the normal group were 8.33%(1/12),16.67%(2/12)and 8.33%(1/12).Compared with the control, the difference were significant (P<0.05). Positive correlation between expression of STAT3 and VEGF, STAT3 and CyclinD1, VEGF and CyclinD1(r=0.631, 0.734, 0.564; P=0.001,0.000,0.005) were found.CONCLUSION: STAT3,VEGF and CyclinD1 may play a role in the development in the incidence of lichen planus,coordination between them may play a role.

Key words: Lichen planus, STAT3, VEGF, CyclinD1, Expression, Relationship