Fig. 5: FUT4-fucosylated L1CAM is required for AR-FUT4-induced melanoma invasiveness.
From: Androgen drives melanoma invasiveness and metastatic spread by inducing tumorigenic fucosylation
a (upper and middle) Fucoproteomic profiling of shNT/shFUT4 (FUT4-knockdown, FUT4-KD) and EV/FUT4-OE WM793 cells identified 8 proteins that are specifically fucosylated by FUT4 and (lower) GeneMANIA interactome mapping of the 8 protein hits highlighting L1CAM as the most centralized signaling protein (adapted from schematic generated in GeneMANIA). b Lectin pulldown (LPD) followed by IB analysis of L1CAM protein in shNT/shFUT4 (left) and EV/FUT4-OE (center) WM793 cells. Column chart (right) shows densitometric quantification for the blots (n = 3 independent experiments). Uncropped blots in Source Data. c Lectin-mediated proximity ligation assay (LPLA) staining for fucosylated-L1CAM (fuco-L1CAM) in shNT/shFUT4 WM793 cells (left; shNT, n = 10 fields; shFUT4, n = 13 fields examined over 3 independent experiments) and EV/FUT4-OE WM793 cells (right; EV, n = 20 fields; FUT4-OE, n = 18 fields examined over 4 independent experiments). Scale bar = 50 μm. d PLA staining for CD15 and L1CAM proteins in EV/FUT4-OE WM793 cells (n = 27 fields examined over 3 independent experiments). Scale bars = 50 μm. e Scratch migration assays of FUT4/L1CAM double-modified WM793 cells (upper; EV-shNT, n = 31 scratches; EV-shL1CAM, n = 32 scratches; FUT4-OE-shNT, n = 33 scratches; FUT4-OE-shL1CAM, n = 30 scratches examined over 3 independent experiments) and shNT/shL1CAM WM793 cells treated ± 100 nM DHT for 48 h (lower; EV-shNT/shL1CAM, n = 36 scratches; FUT4-OE-shNT, n = 34 scratches; FUT4-OE-shL1CAM, n = 31 scratches examined over 3 independent experiments). Scale bar, 400 μm. f Matrigel invasion assay on FUT4/L1CAM double-modified WM793 cells (EV-shNT, n = 17 fields; EV-shL1CAM, n = 16 fields; FUT4-OE-shNT/shL1CAM, n = 17 fields examined over 2 independent experiments). Scale bar = 200 μm. g Working model: During melanoma invasion through the dermis, DHT-activated AR transcriptionally upregulates FUT4, which then triggers melanoma migration and invasion through increased fuco-L1CAM and impaired junction structures (the schematic was created using BioRender). For b–f, data are presented as mean values ± SEM and p-values are calculated by two-sided Student’s t-test. Source data are provided as a Source Data file.
