PDCD1 and cancer: This novel immune checkpoint target has been described as a promising therapy for cancer treatment [124,125], and more than 50 clinical trials are currently recruiting patients or being conducted that involve the use of anti-TIGIT therapies alone or in combination with other immune checkpoint inhibitors, such as PD-1 or PD-L1 (https://clinicaltrials.gov/, accessed on 22 November 2023).