ZNF503 is a transcriptional regulator of the zinc finger protein family, common in PAH and colon cancer, involved in G1 to G0 transition during cell differentiation, development, and tumor initiation, enhancing the proliferation of cancer cells, and inhibiting the expression of other TFs like GATA3, which is related to poor prognostics, an advanced TNM stage, venous invasion, migration, and epithelial–mesenchymal transition progress [157]. Here, ZNF503 is linked to pulmonary arterial hypertension.