NOTCH1 and melanoma: We previously tested the effects of knocking-down WISP-1 by shRNA in the presence of Notch1 signaling pathway activation on melanoma cell proliferation in vitro and melanoma skin growth in vivo. We showed that attenuation of Notch-upregulated WISP-1 expression in fibroblasts could significantly liberate the inhibitory effect of stromal fibroblasts, which is induced by high Notch1 activity, on melanoma growth [16].