C4.4A as a biomarker in pulmonary adenocarcinoma and squamous cell carcinoma

Figure 1 Structure and expression of the protein C4. 4A. A: Schematic outline of the gene cluster encompassing multidomain members of the LU protein family, highlighting the gene encoding C4.4A (LYPD3) and its exon composition. Modified from Kriegbaum et al^[20,24], 2011 and Jacobsen et al^[20,24]; B: Cartoon of the structure of C4.4A. The insert represents the three-finger fold characteristic of LU domains (made in PyMOL, DeLano Scientific, using PDB coordinates 1NEA). Modified from Hansen et al^[19]; C and D: C4.4A expression in suprabasal layers of squamous epithelium, exemplified by tissue-engineered human epidermis (C) and the transition between the glandular and non-glandular portions of the rodent stomach (D). C4.4A is detected by a polyclonal C4.4A antibody and visualized by NovaRED chromogen. D is reproduced with permission from BestPractice Onkologi, Denmark^[89].