CCAAT/enhancer binding proteins (C/EBP) are a group of bZIP transcription factors, consisting of C/EBPalpha, beta, delta, epsilon, gamma and zeta, which can bind as homodimers to certain promoters and enhancers. C/EBP is important in the regulation of genes involved in the immune and inflammatory responses, processes of development, cell proliferation, anti-apoptosis, and many others [1].

C/EBPalpha can form heterodimers with the related proteins, e.g. CEBPbeta [2]. Common targets of C/EBPalpha and beta are: Apolipoprotein B (APOB), which is important for lipid signaling; Synuclein, alpha (Alpha-synuclein), which participates in different neurophysiological process and regulates anti-apoptosis; inflammatory protein Orosomucoid 2 (AGP2 (ORM2)); transporters Serpin peptidase inhibitor, clade A (alpha-1 antiproteinase, antitrypsin), member 6 (SERPINA6) and Alpha-fetoprotein (AFP); and also Haptoglobin (HP), which regulates processes of development and regeneration [3], [4], [5], [6], [7], [8], [9], [10], [11], [12], [13], [14], [15], [16], [17].

C/EBP transcription factors modulate the immune response and inflammation by regulating the transcription of Selectin P ligand (PSGL-1), Orosomucoid 1 (AGP1 (ORM1)), AGP2 (ORM2), Interleukin 5 (IL-5) and HP [5], [18], [19], [20], [21], [22], [23], [24], [25].

In addition, C/EBPalpha may promote cell adhesion and migration by regulation of transcription of PSGL-1 [26].

C/EBPbeta may modulate neurogenesis and other developmental processes by regulating Paired box 2 (PAX2) [27], [28], [29], [30]. Activation of transcription of Hydroxysteroid (17-beta) dehydrogenase 10 (HCD2) by C/EBPbeta influences the cell metabolism [31], [32]. Also, C/EBPbeta regulates the expression of Major vault protein (MVP), which mediates nuclear- cytoplasmic molecular transport [33], [34].

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