COPS5 and gastric cancer: Jab1, also called the fifth subunit of constitutive photomorphogenic‐9 (COP9) signalosome complex (CSN) which implicated in the regulation of protein stability, transcription, protein phosphorylation, and intracellular distribution.[19] Although the role of HIC1 in various malignancies has been well‐documented, its precise mechanisms in gastric cancer remain inadequately elucidated.