Hair Follicular Expression of Integrin Alpha-6 Subunit and p63 in Hair Loss

Kang, Hoon; Lee, Ye Jin; Park, Young Min; Kim, Si Yong; Kim, Hyung Ok; Lee, Seung Dong

Abstract

BACKGROUND: Integrins have a crucial function in the attachment of cells to the extracellular matrix and as important transducers of signals from the extracellular matrix to the matrix cells of the hair follicle. Recent evidence has suggested that p63 is essential for the development of epidermis and skin appendages.
OBJECTIVE
To investigate the possibility that integrin alpha-6 and p63 may be involved in the pathogenesis of various conditions of hair loss.
METHODS
The expressions of integrin alpha-6 subunit and p63 were examined by immunohistochemical staining of 76 scalp biopsy samples, including 21 male pattern hair loss (MPHL), 19 female pattern hair loss (FPHL), 23 alopecia areata (AA) and 13 female telogen effluvium (TE). In each staining section, the percentage of positive cells and the localization of expression were evaluated.
RESULTS
Among the four hair loss groups, MPHL and AA showed nearly negative immunoreactivities of alpha-6 integrin in the basal sides of follicle epithelium. On the other hand, TE immunoreactivity represented very similar pattern of normal control and FPHL samples showed weak outer root sheath staining which was definitely different from that of MPHL. Immunohistochemical staining of p63 in AA and TE revealed relatively strong reactivity compared to MPHL and FPHL. Interestingly, TE p63 immunoreactivity was mainly confined to inner 2/3 outer root sheath.
CONCLUSION
These data may explain the somewhat causal and developmental role of integrin alpha-6 and p63 in the occurrence of hair loss. Since both integrin alpha-6 and p63 are necessary for hair follicle growth and maintenance, it is worthwhile taking more concern over these proteins.