Table 2.
Identified Species Selected by Lasso as Significant Contributors to the Molecular Model for IDC- and Normal-Breast-Tissue Classification with Attributed Statistical Weightsa
| measured m/z | lipid assignment | exact m/z | mass error (ppm) | proposed formula | Lasso weight |
|---|---|---|---|---|---|
| Characteristic of Normal Breast Tissue | |||||
| 742.539 | PE(36:2) | 742.539 | −0.4 | C41H77NO8P | −213.0 |
| 769.502 | PG(36:4) | 769.503 | −0.9 | C42H74O10P | −189.6 |
| 792.530 | PC(34:2) | −174.7 | |||
| 750.545 | PE(O-38:5) | 750.544 | 0.7 | C43H77NO7P | −169.4 |
| 786.529 | PS(36:2) | 786.529 | −0.4 | C42H77NO10P | −166.3 |
| 778.539 | PE(39:5) | 778.539 | −0.6 | C44H77NO8P | −149.5 |
| 748.528 | PE(O-38:6) | 748.529 | −0.8 | C43H75NO7P | −148.1 |
| 727.527 | PA(38:2) | 727.528 | −1.9 | C41H76O8P | −133.6 |
| 734.534 | PS(O-33:0) | 734.534 | −0.3 | C39H77NO9P | −105.0 |
| 891.722 | TG(52:3) | 891.721 | 0.3 | C55H100O6Cl | −104.6 |
| 770.534 | PS(P-36:2) or PS(O-36:3) | 770.534 | 0.1 | C42H77NO9P | −39.8 |
| 700.602 | Cer(t42:1) | 700.602 | 0.4 | C42H83NO4Cl | −38.8 |
| 816.576 | PS(38:1) | 816.576 | −0.6 | C44H83NO10P | −32.9 |
| 788.545 | PS(36:1) | 788.544 | 0.6 | C42H79NO10P | −25.3 |
| 752.553 | PE(O-38:4) | 752.560 | −9.0 | C43H79NO7P | −24.8 |
| 885.550 | PI(38:4) | 885.550 | −0.3 | C47H82O13P | −19.9 |
| 837.547 | PI(34:0) | 837.550 | −3.9 | C43H82O13P | −14.3 |
| 794.55 | PC(34:1) | −14.1 | |||
| 723.478 | CL(72:8) | 723.479 | −0.8 | C81H140O17P2 | −4.7 |
| 724.485 | CL(72:7) | 724.487 | −2.6 | C81H142O17P2 | −2.5 |
| Characteristic of IDC Tissue | |||||
| 846.657 | PS(O-41:0) | 846.659 | −3.3 | C47H93NO9P | +12.3 |
| 835.534 | PI(34:1) | 835.534 | −0.7 | C43H80O13P | +17.2 |
| 887.564 | PI(38:3) | 887.566 | −2.3 | C47H84O13P | +18.1 |
| 838.559 | PS(40:4) | 838.560 | −1.6 | C46H81NO10P | +34.3 |
| 773.533 | PG(36:2) | 773.534 | −0.8 | C42H78O10P | +56.2 |
| 760.513 | PS(34:1) | 760.513 | −0.3 | C40H75NO10P | +90.8 |
| 766.539 | PE(38:4) | 766.539 | 0.0 | C43H77NO8P | +116.4 |
| 810.525 | PS(38:4) | 810.529 | −4.9 | C44H77NO10P | +120.4 |
| 819.517 | PG(40:7) | 819.518 | −0.9 | C46H76O10P | +169.3 |
| 747.517 | PG(34:1) | 747.518 | −0.9 | C40H76O10P | +187.9 |
| 861.549 | PI(36:2) | 861.550 | −0.7 | C45H82O13P | +237.7 |
a
Chemical species were tentatively identified by high-mass-accuracy–high-mass-resolution and tandem MS analyses. Positive weights are given to m/z that are indicative of IDC, whereas negative weights are given to m/z that are indicative of normal breast tissues.