PURPOSE: There are currently no consistently effective treatments for the excessive collagen produced by keloid fibroblasts. Previously, we reported that heat shock protein 70 (Hsp70) is up-regulated in keloid fibroblasts and keloid tissue. We, therefore, investigated whether Hsp70 is related to excessive collagen production in keloid fibroblasts. MATERIALS AND METHODS: We inhibited Hsp70 in keloid fibroblasts by RNA interference and examined the resulting collagen expression. Thus, we selected small interfering RNAs (siRNAs) specific for human Hsp70, transfected them into keloid fibroblasts, and evaluated the resulting phenotypes and protein production using real-time polymerase chain reaction (PCR), Western blot, and a collagen assay. RESULTS: The siRNAs dramatically suppressed Hsp70 mRNA expression, resulting in a decrease in collagen production in the keloid fibroblasts compared with controls. The siRNAs did not influence the viability of the keloid fibroblasts. CONCLUSION: Hsp70 overexpression likely plays an important role in the excessive collagen production by keloid fibroblasts. RNA interference has therapeutic potential for the treatment of keloids.
Adolescent ; Adult ; Blotting, Western ; Collagen/*drug effects/metabolism ; Female ; Fibroblasts/metabolism ; Gene Expression Regulation ; HSP70 Heat-Shock Proteins/genetics/metabolism/*pharmacology ; Humans ; Keloid/*drug therapy/genetics/metabolism ; Male ; RNA, Messenger/*genetics ; RNA, Small Interfering/*genetics ; Real-Time Polymerase Chain Reaction ; Transfection ; Up-Regulation