Spontaneous basal activation that might be related to survival mechanism of tumor cells by allowing them to escape from apoptosis has been proven in some tumor cells, but it has not been evaluated in malignant melanoma tissue.

The purpose of this study was to evaluate basal activation of NF-κB using immunohistochemical analysis and demonstrate its clinical significance in cutaneous malignant melanoma tissue.

Twenty-five cases of acral lentiginous melanoma(ALM) from 20 patients were selected. Immunohistochemical analysis was performed to detect nuclear localization of classic NF-κB heterodimer, p50 and p65 in the formalin-fixed, paraffin-embedded tissues.

In about 50% of cases, nuclear expression of NF-κB heterdimer, p50 and p65 was detected, 12(48%) and 13(52%) of 25 cases of ALM, respectively. However, the nuclear ex-pressing of p50 and p65 was not significant for tumor thickness or level of invasion in ALM.

We demonstrated basal NF-κB activation in malignant melanoma, but we need to research further to demonstrate its clinical significance.