CUL4B and liver cancer: CRL4B is a component of CRL4B that can target different substrates for protein modification or proteasomal degradation.13 Recently, high expression levels of CUL4B have been found in a variety of human malignancies, such as cervical cancer, esophageal cancer, liver cancer, and osteosarcoma, and these enhanced expression levels are positively correlated with tumor progression.11, 14, 15, 16 Our study showed that CUL4B upregulation in HNSCC tissues was associated with worse tumor grade and shorter survival.