Clinical trials using BTK inhibitors are known to target different cancer including GBM (NCT03535350), prostate (NCT02643667), oesophagogastric (NCT02884453), refractory colorectal (NCT03332498), and immune cell populations in COVID-19 disease (NCT04382586, NCT04439006, and NCT04346199). Here, BTK is linked to cancer.