Table II

Identified epithelial cellular proteins with described involvement in OSCC progression

GPI, glycosylphosphatidylinositol; TCR, T-cell receptor.

UniProt no.Gene nameProtein name (Nup/Nsma)Subcellular localizationDescriptionRef.
OSCC signaling pathways
    P40763 STAT3 Signal transducer and activator of transcription 3 (1/8)Cytoplasm/nucleusTranscription factor that binds to the interleukin-6-responsive elements.41–43
    O43353 RIPK2 Receptor-interacting serine/threonine-protein kinase 2 (2/2)CytoplasmActivates NF-κB.43, 57
    O14920 IKBKB Inhibitor of nuclear factor κB kinase subunit β (1/3)CytoplasmActivates NF-κB by phosphorylating its inhibitors, leading to their degradation.58, 59
    P30048 PRDX3 Thioredoxin-dependent peroxide reductase, mitochondrial (3/14)MitochondrionInvolved in redox regulation of the cell. Acts synergistically with MAP3K13 to regulate the activation of NF-κB in the cytosol.60, 61
OSCC tumor markers
    P29508 SCCA1 Serpin B3 (3/5)CytoplasmMay act as a protease inhibitor to modulate the host immune response against tumor cells. 45
    P48594 SCCA2 Serpin B4 (8/23)CytoplasmMay act as a protease inhibitor to modulate the host immune response against tumor cells. 45
OSCC cell adhesion and growth
    P27701 CD82 CD82 antigen (3/9)Multipass membrane proteinAssociates with CD4 or CD8 and delivers costimulatory signals for the TCR/CD3 pathway. 62
    P08195 SLC3A2 4F2 cell surface antigen heavy chain (4/9)Single pass type II membrane proteinInvolved in sodium-independent, high affinity transport of large neutral amino acids. Required for normal and neoplastic cell growth. 63
    Q14210 LY6D Lymphocyte antigen Ly-6D (1/19)Cell membrane; lipid anchor; GPI anchorMay be involved in cell-cell adhesion and signal transduction. 64
    P21926 CD9 CD9 antigen (4/56)Multipass membrane proteinInvolved in platelet activation and aggregation. Involved in cell adhesion, cell motility, and tumor metastasis. 65
    P09758 TACSTD2 Tumor-associated calcium signal transducer 2 (6/47)Single pass type I membrane proteinGA733 tumor-associated antigen gene family may function as growth factor receptors. 66
  • a Nup, number of unique peptides identified from the protein. Supporting MS/MS spectra for the proteins STAT3, IKBKB, and LY6D, identified from single peptide sequences, are shown in Supplemental Table 1. Nsm, total number of MS/MS spectrum matches for the protein.