PDCD1 and cancer: Furthermore, the United States Food and Drug Administration (FDA) approved sorafenib (Nexavar) and nivolumab (OPDIVO, Bristol-Myers Squibb Co.)as the first anti-PDL-1/PD-1 antibodies for the treatment of HCC in 2007 and 2017, respectively, confirming that ICIs may play a key role in HCC treatment and offer hope for patients with cancer [17,18].