β-catenin can act as a transcriptional co-factor for Smad3, activating the transcription of downstream target genes and promoting EMT.358 Additionally, TGF-β1 can activate the Wnt/β-catenin signaling pathway by inhibiting DKK1 expression, a negative regulator of Wnt signaling.359 In pathological conditions such as CKD, increased levels of Wnt9a lead to renal tubular cell senescence and the initiation of TGF-β1 production. The gene discussed is WNT9A; the disease is chronic kidney disease.