P8.111 Microarray analysis of IGF-I and IGF-II regulated gene expression in human dermal papilla fibroblasts.

JJ Bull, Y Liu, J Monson*, O, Djahanbakhch ⁺. MP Philpott

Centre for Cutaneous Research, *Department of Endocrinology and Department of Obstetrics and Gynaecology, Barts and the London Queen Marys School of Medicine and Dentistry. University of London.

Objectives: IGF-I has been strongly implicated as an important regulator of hair growth and the hair growth cycle. IGF-I receptors are located on the dermal papilla and it has been suggested that IGF-I may act via these receptors to stimulate secretion of factors that are important regulators of the hair growth cycle. Little is known about the actions of IGF-I on dermal papilla fibroblasts. The objectives of this study have been to use microarray analysis to identify genes that are regulated by IGF-I and IGF-II in cultured human dermal papilla fibroblasts.

Methods: Human dermal papilla fibroblasts were isolated from redundant human facelift skin and cultured in vitro using previously described methods. Passage 2-3 cells were incubated with IGF-I (10 ngml), IGF-II (100ngml) or with an IGF-IR blocking antibody for 24hrs. Following RNA extraction and cDNA synthesis array analysis was carried out using Affymetrix gene chips.

Results: We have identified a number of genes that are upregulated  by IGF-I and IGF-II. The genes induced by IGF-I and IGF-II were generally those involved in cell proliferation and differentiation. Further analysis of these data are required to confirm their IGF-I and IGF-II regulation. These data are also being used in conjunction with gene array studies of hirsute and non hirsute derived dermal papilla fibroblasts in an attempt to identify underlying mechanisms of hirsutism.