Li et al. used Anti-EpCAM antibody to modify reduced graphene oxide (rGO) films, which showed extreme sensitivity to CTC, and could efficiently capture CTC from fresh whole blood, with high specificity and low background.213 In addition to the above specific ligand modifications, a variety of tumor cell surface markers such as CD44, CD47, CD20, CD147, CD31 have been identified as effective targets for specific and selective anti-tumor therapy.214–216 These proteins are involved in tumor proliferation, invasion and metastasis, and play a pivotal role in tumor occurrence and development. The gene discussed is CD44; the disease is neoplasm.