Intense picosecond THz pulses alter gene expression in human skin tissuein vivo

Abstract

Pulsed terahertz (THz) imaging has been suggested as a novel high resolution, noninvasive medical diagnostic tool. However, little is known about the influence of pulsed THz radiation on human tissue, i.e., its genotoxicity and effects on cell activity and cell integrity. We have carried out a comprehensive investigation of the biological effects of THz radiation on human skin tissue using a high power THz pulse source and an <i>in vivo</i> full-thickness human skin tissue model. We have observed that exposure to intense THz pulses causes DNA damage and changes in the global gene expression profile in the exposed skin tissue. Several of the affected genes are known to play major roles in human cancer. While the changes in the expression levels of some of them suggest possible oncogenic effects of pulsed THz radiation, changes in the expression of the other cancer-related genes might have a protective influence. This study may serve as a roadmap for future investigations aimed at elucidating the exact roles that all the affected genes play in skin carcinogenesis and in response to pulsed THz radiation.