ATF4 and neoplasm: NK_c3 and NK_c5 were mainly derived from non-tumor liver tissues (23.57% and 5.97%, respectively) and characterized by high expression of transcription factors such as FOS, FOSB, FOXP1, and ATF4, and two genes involved in the NF-κB pathway, NFKBIA and NFKBIZ (Fig. 4c; Supplementary Fig. S4e).