TMPRSS4 and thyroid cancer: For example, some proteases in thyroid cancer are elevated in tumors (67):transmembrane protease serine 4 promotes thyroid cancer proliferation through cAMP response element-binding protein (CREB) phosphorylation (68), and the HIV protease inhibitor nefinavir induces apoptosis of thyroid medulla cancer cells by downregulating RET signalling (69).