REL and neoplasm: Similarly, SP cells from both HPV16+ve and HPV-ve tumor biopsies showed strong expression of all NF-κB family proteins, i.e. p50 (0.001), p52 (0.001), p65 (0.001), c-Rel (0.001), and RelB (0.001) with respect to their NSP and parental cells (Fig 6A and 6B).