Table 1.
Selected proteins detected with abundant biotinylated peptides and their known association with prostate cancer
| Protein | Number of biotinylated extracellular lysine residues/number of all extracellular lysines (percent) | Association with plasma membrane | Relevance in prostate cancer | |
|---|---|---|---|---|
| 1 | CD59 | 4/7 (57%) | GPI-anchored | Associated with disease progression and adverse prognosis [27] |
| 2 | Neuropilin-1 (NRP1) | 38/53 (72%) | Single-pass type I membrane protein | Promotes progression through EGFR/AKT signaling axis [30] |
| 3 | Integrin beta-1 (ITGB1) | 34/49 (69%) | Single-pass type I membrane protein | Involved in oncogenic TGF-b signaling [38] |
| 4 | CD166 (ALCAM) | 28/37 (76%) | Single-pass type I membrane protein | Marker of prostate cancer progression; regulates bone metastasis [28] |
| 5 | Ephrin type-A receptor 2 (EPHA2) | 14/18 (78%) | Single-pass type I membrane protein | Involved in metastasis [50] |
| 6 | Complement decay-accelerating factor (CD55) | 11/19 (58%) | GPI-anchored | Promotes cancer cell survival and tumor growth [51] |
| 7 | Transferrin receptor protein 1 (TFRC) | 35/46 (76%) | Single-pass type II membrane protein | Induces proliferation, migration and invasion in cell lines; ferroptosis-related biomarker [36, 37] |
| 8 | CUB domain-containing protein 1 (CDCP1) | 20/32 (63%) | Single-pass type I membrane protein | Highly expressed in castration-resistant prostate cancer; therapeutic target [52, 53] |
| 9 | Cadherin-11 (CDH11) | 19/31 (61%) | Single-pass type I membrane protein | Increases migration and invasion [54] |
| 10 | 5′-Nucleotidase (NT5E, CD73) | 27/35 (77%) | GPI-anchored | Suppresses immune surveillance, prognostic factor [55] |
| 11 | Integrin alpha-6 (ITGA6, CD49F) | 33/64 (52%) | Single-pass type I membrane protein | Marker of prostate cancer; necessary for self-renewal activity of prostate stem cells [39, 40] |
| 12 | Basigin (BSG, CD147) | 8/12 (67%) | Single-pass type I membrane protein | Associated with progression; stimulates production of matrix metalloproteases [56, 57] |
| 13 | Integrin alpha-2 (ITGA2, CD49b) | 27/54 (50%) | Single-pass type I membrane protein | Promotes prostate cancer cell growth within bone [41] |
| 14 | Inactive tyrosine-protein kinase 7 (PTK7) | 16/24 (67%) | Single-pass type I membrane protein | Prognostic biomarker; predictor of lymph node metastasis [58] |
| 15 | 4F2 cell-surface antigen heavy chain (SLC3A2) | 14/20 (70%) | Single-pass type II membrane protein | Promotes progression via S-phase kinase-associated protein 2 (SKP2) [33] |
| 16 | Hepatocyte growth factor receptor (MET) | 29/52 (56%) | Single-pass type I membrane protein | Highly expressed in bone metastasis [59, 60] |
| 17 | Glypican-4 (GPC4) | 25/37 (68%) | GPI-anchored | Interacts with stromal cells; extracellular matrix remodeling, endocrine/paracrine signaling [61] |
| 18 | Melanoma cell adhesion molecule (MCAM) | 15/23 (65%) | Single-pass type I membrane protein | Involved in metastasis by mediating E-selectin-dependent interaction with bone marrow endothelium [62, 63] |
| 19 | Adhesion G protein-coupled receptor E5 (ADGRE5, CD97) | 12/24 (50%) | Multi-pass membrane protein | Mediates invasion of prostate cancer cells in association with lysophosphatidic acid receptor 1 (LPAR1) [64] |
| 20 | Epidermal growth factor receptor (EGFR) | 19/36 (53%) | Single-pass type I membrane protein | Marker of dissemination to bones [29] |