T helper type 1 cytokines and keratinocyte growth factor play a critical role in pseudoepitheliomatous hyperplasia initiation during cutaneous leishmaniasis
Immunolocalization studies using the strepavidin/biotin peroxidase system were used to identify epidermal growth factor receptors in 10 samples of normal skin, 13 seborrhoeic warts (SW), five lesions of Bowen's disease (BD), 11 solar keratoses (SK), 22 basal cell carcinomas (BCC) and five squamous cell carcinomas (SCC). The intensity of cell membrane staining was assessed using the 10-cm visual analogue scale technique and the results analysed using non-parametric statistics. The cell membranes in BCC showed significantly less intense staining when compared to normal epidermal cells (P less than 0.001) and the constituent cells of SW (P less than 0.001), SK (P less than 0.001), BD (P less than 0.01), and SCC (P less than 0.001). Classification of the specimens into normal, benign, premalignant and malignant indicated that cell membranes of malignant tumours showed significantly less staining than the other groups (P less than 0.001). The observed reduction in the epidermal growth factor receptors in malignant tumours may be due to occupation and down regulation in response to autocrine secretion of growth factors.