Table 2.
List of selecteda secreted proteins observed across the MCF10 cell lines, documented by their position in the Mascot search list and the combined number of peptide matched in the combined search data b.
| Protein Name | NCBInr gi # | MCF10A e | MCF10AT | MCF10 DCIS.com c | MCF10CA cl. D | ||||
|---|---|---|---|---|---|---|---|---|---|
| Mascot position | Sequences matched | Mascot position | Sequences matched | Mascot position | Sequences matched | Mascot position | Sequences matched | ||
| Annexin 1 c | 4502101 | 10 | 42 | 6 | 46 | 14 | 32 | 3 | 83 |
| Annexin A2, isoform 2 c | 4757756 | 3 | 63 | 3 | 80 | 3 | 114 | 2 | 134 |
| Cathepsin D preprotein | 4503143 | 88 | 13 | 21 | 47 | 9 | 66 | 19 | 93 |
| Clusterin isoform 1 c | 42716297 | 197 | 3 | 5 | 65 | ||||
| Cystatin B | 4503117 | 70 | 9 | 169 | 4 | 151 | 4 | 79 | 24 |
| Cystatin C precursor | 4503107 | 25 | 22 | 25 | 21 | 87 | 17 | ||
| Dystroglycan 1 precursor | 4758116 | 189 | 1 | 96 | 5 | 39 | 16 | 90 | 11 |
| Enolase 1 c | 4503571 | 1 | 94 | 2 | 100 | 4 | 85 | 1 | 188 |
| Galectin-3-binding protein (LGAL3BP) | 5031863 | 76 | 18 | 2 | 133 | 7 | 75 | ||
| Glutathione transferase c | 4504183 | 4 | 34 | 4 | 42 | 19 | 22 | 23 | 40 |
| H2A histone family, member E c | 10800144 | 6 | 51 | 16 | 57 | 8 | 48 | 5 | 111 |
| Lipocalin 2 | 38455402 | 6 | 76 | ||||||
| Lysyl oxidase preproprotein (LOX) | 20149540 | 118 | 4 | 116 | 7 | 332 | 2 | ||
| Mesothelin isoform 1 preproprotein (MSLN) | 53988378 | 46 | 24 | 77 | 16 | ||||
| Nucleophosmin 1 isoform 1 c | 10835063 | 22 | 37 | 10 | 62 | 24 | 21 | 8 | 105 |
| Peptidylprolyl isomerase isoform 1 (Cyclophilin A) | 10863927 | 5 | 61 | 14 | 58 | 22 | 34 | 9 | 119 |
| Peroxiredoxin 1 c | 32455266 | 37 | 21 | 34 | 19 | 44 | 16 | 47 | 35 |
| Plasminogen activator inhibitor type 1, member 2 | 24307907 | 167 | 9 | 161 | 10 | ||||
| Profilin 1 | 4826898 | 26 | 29 | 11 | 36 | 30 | 23 | 4 | 97 |
| Quiescin Q6 isoform a | 13325075 | 175 | 2 | 7 | 56 | 42 | 19 | ||
| S100 calcium-binding protein A13 | 5174659 | 231 | 4 | 202 | 3 | ||||
| S100 calcium-binding protein A14 | 10190712 | 210 | 2 | 45 | 18 | 66 | 13 | ||
| S100 calcium-binding protein A16 | 17933772 | 156 | 2 | 140 | 1 | 20 | 22 | 68 | 13 |
| S100 calcium-binding protein A2 | 5174661 | 110 | 12 | 75 | 28 | 46 | 32 | ||
| S100 calcium-binding protein A6 | 7657532 | 84 | 25 | 91 | 11 | 119 | 11 | 112 | 17 |
| S100 calcium-binding protein P | 5174663 | 16 | 21 | 170 | 6 | 113 | 12 | ||
| Secreted frizzled-related protein 1 | 56117838 | 113 | 15 | 286 | 9 | ||||
| Secreted modular calcium-binding protein 1 isoform 2 | 11545873 | 13 | 29 | 45 | 27 | ||||
| Secreted protein, acidic, cysteine-rich (Osteonectin, SPARC) d | 4507171 | 31 | 40 | 2 | |||||
| Serine (or cysteine) proteinase inhibitor, clade A (AAT) | 50363217 | 12 | 55 | 81 | 14 | ||||
| Serine (or cysteine) proteinase inhibitor, clade B (ovalbumin) | 4505789 | 238 | 5 | 213 | 3 | 231 | 13 | ||
| Serpin peptidase inhibitor (AACT) | 50659080 | 65 | 8 | 1 | 323 | 6 | 87 | ||
| Syndecan 1 precursor | 55749480 | 89 | 3 | 68 | 7 | 162 | 6 | ||
| Thrombospondin 1 precursor | 40317626 | 118 | 5 | 93 | 8 | 34 | 23 | 136 | 15 |
| Tissue inhibitor of metalloproteinase 1 precursor | 4507509 | 201 | 2 | 46 | 10 | 46 | 11 | 53 | 23 |
| Transforming growth factor | 4507467 | 176 | 10 | 1 | 176 | 126 | 1 | 41 | 34 |
| Zinc alpha-2-glycoprotein 1 (ZAG) | 4502337 | 24 | 28 | 94 | 5 | 61 | 8 | ||
Proteins listed were selected from over 200 from each proteome. The selection was based on their appearance high on the Mascot list and/or their significant change across cell lines.
Data from all search files from each secreted proteome (5 fractions each preparation, 3 preparations with 2 analyzed in duplicate) were combined and searched with Mascot against the RefSeq database from NCBI. The “most abundant” protein with the highest score is listed as Mascot position #1. The number of peptides include those that matched across all LC-MS/MS analyses. If a protein was not detected above the threshold score, a blank entry is used.
These proteins, while considered cytosolic, are predicted to be secreted by non-classical mechanisms using SecretomeP.
The SPARC in MCF10CA gave a Mascot score one point below the threshold and thus did not receive a position. It did have two peptides, one of which was manually sequenced and uniquely identified the protein.
The second most abundant protein in MCF10A and fifth in MCF10 DCIS.com was a keratin. This was consistently present in the three preparations of these cell lines.