Figure 2

Murine melanomas induce paracrine β-catenin signaling activation in tumor and TDLN DCs in vivo . A.Tumor-infiltrating DCs (TIDCs) isolated from Tyr::CreER;Braf^CA;Pten^lox/lox primary melanomas exhibit increased expression levels of β-catenin target genes, including axin2, ccnd1, c-myc, and tcf-7, based on qrt-PCR relative to BMDCs derived from non-tumor bearing mice. Representative of 2 independent experiments. P value based on a two-way ANOVA. B. DCs isolated from tumor-draining lymph node (TDLN) tissues harvested from melanoma-bearing Tyr::CreER;Braf^CA;Pten^lox/lox mice exhibit elevated expression levels of β-catenin target genes relative to distant LN tissues harvested from the same mice as well as LN tissues harvested from non-tumor-bearing cre^- control mice. Representative of 2 independent experiments. P value based on a two-way ANOVA. C. β-catenin signaling activation in CD11c⁺ DCs derived from primary BRAF^V600EPTEN^-/- melanomas and TDLNs harvested from TCF/Lef1-EGFP reporter mice. Left, flow cytometry analysis and quantitation of GFP⁺CD11c⁺ DCs. Representative of 2 independent experiments. Right, immunofluorescence confocal microscopy of a GFP⁺CD11c⁺ DC isolated from a BRAF^V600EPTEN^-/- primary melanoma. D. Confocal microscopy of a resected BRAF^V600EPTEN^-/- melanoma resected from a TCF/Lef1-EGFP reporter mouse demonstrates a GFP-positive stromal infiltrate. Representative of 3 analyzed tumors. 60x. E. Left, Confocal immunofluorescence microscopy of TDLN tissue resected from TCF/Lef1-EGFP reporter mice demonstrates evidence of GFP⁺ lymph node cells. Center, TDLN tissue resected from wild type (WT) BRAF^V600EPTEN^-/- melanoma-bearing mice. Right, TDLN tissue from TCF/Lef1-EGFP reporter mice counterstained for CD11c expression shows evidence of GFP⁺CD11c⁺ DCs (arrows). Representative of 3 analyzed lymph nodes. 60x.