The simultaneous upregulation of H2S biosynthesis and H2S degradation in DS shows parallels with the situation in colon cancer cells: in epithelial cell organoids the sequential introduction of various cancer-associated mutations not only induces the upregulation of CBS and 3-MST, but also triggers the upregulation various H2S-decomposing enzymes, which partially compensate for the increased H2S production rate [86]. The gene discussed is CBS; the disease is malignant colon neoplasm.