LEF1 and melanoma: This local paracrine β-catenin signaling effect was then confirmed in situ within the melanoma stroma and within TDLN tissues by confocal microscopy using the Tg(TCF/Lef1-HIST1H2BB/EGFP)61Hadj/J transgenic reporter strain, which encodes an EGFP reporter downstream of a β-catenin-responsive promoter containing tandem TCF/LEF1 transcription factor binding elements (65).