Our findings, which to our knowledge are the first to suggest a pharmacological-like response of fibroblasts to exogenously applied CO2, are consistent with the results of a study by Tadokoro et al. that has focused on the impact of CO2 on the expression of TGF-β and α-SMA of cancer-associated fibroblasts in a mouse model in vitro. The gene discussed is ACTA1; the disease is cancer.