OBJECTIVETo investigate whether there are abnormal fibroblasts in the surrounding skin of keloids for better understanding of the etiological feature of keloids.

METHODSFresh samples were used for cell culture. Flow cytometry was used for analyzing cell cycles of fibroblasts derived from keloids and the surrounding skin. Proliferative cell proportions were compared between every two groups. P53 exon 4, 5 and 6 were amplified by PCR. DNA was sequenced to examine the structure of the destination gene.

RESULTSThe proliferative cell proportion of the fibroblasts derived from the surrounding skin is not so high as that from the verge of keloids, but is higher than the normal skin fibroblasts derived from other part of the keloid patients or persons without keloids (P < 0.05). Mutations (point and frameshift mutations) of P53 exon 4 (6/6) and exon 5(2/6) in fibroblasts derived from the surrounding skin of keloids were identified. Fibroblasts derived from keloids have the same mutations as its surrounding skin.

CONCLUSIONThere are abnormal fibroblasts in the surrounding skin of keloids. It may be the consequence of keloid infiltrative growth and a reason of easy recurrence of keloid after therapy.