Author(s): Nagwa M Elwan, Amal A El-Ashmawy, Shereen F Gheida and Omnia K Rizk
Stem Cell Factor (SCF) is generally thought to be an important regulator of melanocyte and mast cell survival, migration and proliferation. The c-kit receptor (CD117) may play a role in many skin disorders with dyspigmentation. The aim of this study was to assess the immunohistochemical expression of CD117 in some pigmentary disorders such as melasma and vitiligo. The study included a total of 40 patients were divided into two groups; melasma group: included (20) patients and vitiligo group: included (20) patients, in addition to a control group which included (20) healthy skin specimens were obtained during plastic operations. The severity of melasma and vitiligo skin lesions were measured by modified melasma and area severity index (MASI) and vitiligo area severity index (VASI) scores respectively. Tissue biopsies were taken from all the participant and stained by haematoxylin and eosin (H and E) and immunohistochemical staining for c-kit antibody. Normal skin: The intensity of c-kit expression was mild to moderate positivity. Melasma: The intensity of c-kit expression showed significant increase when its expression was compared with control group. There was statistically significant positive correlation between the intensity of c-kit expression in both melasma groups when compared with modified MASI score. Vitiligo: c-kit expression was negative in the epidermis. There was significant decrease in the intensity of c-kit expression in vitiligo when compared with control group. There was statistically significant negative correlation between the intensity of c-kit expression in both vitiligo groups when compared with VASI score. We concluded that c-kit may play a role in the pathogenesis of some dyspigmentary disorders as melasma and vitiligo. It could be used as a marker for melasma severity. So, c-kit may be considered the main target in the treatment of these diseases.