PURA and esophageal squamous cell carcinoma: In addition, an immunofluorescence assay indicated that PURα and PABPC1 or EIF3B were both colocalized in the cytoplasm in ESCC cells and tissues, respectively, both in vitro and in vivo (Fig. 4E, F), implying that cytoplasmic PURα likely recruits translation initiation factors to modulate protein expression, consistent with the characteristics of cytoplasmic stress granules, which represent assemblies of mRNPs stalled in translation initiation [32, 33].