Evaluation of Hair Follicles as a Surrogate Tissue for Pharmacodynamic Response in Xenograft Tumors

The study evaluated hair follicles as a surrogate tissue for pharmacodynamic response in xenograft tumors, aiming to facilitate rapid drug development in oncology. Using a Notch-driven mouse xenograft model responsive to a gamma-secretase inhibitor, researchers compared plucked hair, skin biopsies, and whiskers as surrogate tissues. They induced hair growth synchronization in mice and collected various samples during each hair cycle phase. A qPCR assay was developed for hair phase identification, and gene expression patterns were analyzed. The findings suggested that hair follicles could serve as a reliable surrogate tissue, potentially enabling quicker clinical decisions regarding target modulation and treatment.