DKK3 and lung cancer: Our finding that Dkk-3 suppressed tubular Wnt/β-catenin signaling in proteinuric nephropathy was in line with other experiment, which showed that Dkk-3 is an inducer of apoptosis31, 38 and inhibition of this protein leads to the activation of Wnt/β-catenin signaling in lung cancer.39 Our findings should ideally be confirmed using cell-specific Dkk-3 knockout animal models, or using a Dkk-3 neutralizing antibody.