Breast cancer research : BCR
July 18, 2026 · via Europe PMC
Diagnostic plasma protein signatures in sporadic and BRCA1/2 breast cancer patients via targeted proteomics.
Holm KY, Mohammed Y, Gunnarsdottir Thormar V, +5 more, Bodvarsdottir SK.
AI summary — for doctors, generated from the abstract only
Targeted plasma proteomics identified protein changes that differ by breast cancer subtype, including lower IGHM and CD5L in BRCA1/2 carriers, some detectable up to 5 years before diagnosis.
What was studied
Absolute quantification of 98 plasma proteins by UPLC-MRM-MS in 135 breast cancer patients (one-third BRCA1/2 carriers) and paired controls, including women diagnosed within 5 years after blood collection.
Key findings
- Four proteins elevated and four reduced across subgroups
- Haptoglobin elevated in sporadic and grade 3 cases; LBP in node-positive and HER2 cases
- IGHM and CD5L lower in BRCA1/2 and triple-negative patients, and lower in BRCA2 carriers before diagnosis
- LBP, haptoglobin and IGHM associated with breast cancer-specific survival
Clinical relevance
This is exploratory biomarker discovery with no current clinical application, though it is potentially relevant to future screening of high-risk carriers.
Who should care
Limitations
Small subgroups (e.g., n=7 BRCA2 pre-diagnosis); multiple comparisons; no validation cohort.
Blood proteins may one day help screen BRCA carriers, but these findings are preliminary.
This is an AI-generated summary of the published abstract, not a clinical recommendation. It may not reflect the full text or subsequent updates — verify against the original source before acting on it.
Abstract
Background
Early breast cancer diagnosis is critical, particularly for individuals at hereditary risk. The aim of this study was to identify blood-derived protein biomarkers for breast cancer diagnosis to improve current screening strategies.
Methods
Absolute quantification of 98 plasma proteins was performed via a UPLC-MRM-MS assay on plasma samples from 135 breast cancer patients and paired controls, one-third of which were of hereditary BRCA1/2 origin, and from women diagnosed within 5 years from blood collection. Plasma protein concentration profiles were compared between patients and paired controls across breast cancer subgroups.
Results
Proteomic analysis revealed four plasma proteins with elevated abundance and four other proteins with reduced abundance across different breast cancer subgroups. Haptoglobin (HP) was elevated in sporadic cases (n = 88) and cases with grade 3 tumors (n = 44), adipocyte plasma membrane-associated protein was elevated in cases with large tumors (n = 60) and grade 3 tumors (n = 44), lipopolysaccharide-binding protein (LBP) was elevated in node-positive (n = 58) and HER2 (n = 9) cases, and secreted protein acidic and cysteine rich was elevated in luminal B (n = 45) cases. Transthyretin was reduced in luminal B patients, and apolipoprotein A4 was reduced in HER2 patients. Immunoglobulin heavy constant mu (IGHM) and CD5 antigen-like (CD5L) were lower in BRCA1/2 (n = 47) and triple-negative (n = 17) patients than in paired controls. IGHM and CD5L were also lower in BRCA1/2 patients than in paired sporadic patients. Additionally, IGHM in plasma was lower among BRCA2 mutation carriers (n = 7) diagnosed with breast cancer within 5 years of blood collection than among paired controls and CD5L was also lower than among paired controls and sporadic patients diagnosed within 5 years of blood collection. The plasma proteins associated with breast cancer specific survival were LBP, HP, and IGHM.
Conclusions
These findings indicate that plasma protein concentrations may have diagnostic and prognostic value for breast cancer screening and could provide valuable insights for biomarker discovery.
DOI
10.1186/s13058-026-02348-y
PMID
42471715
Research metadata (titles, abstracts, authors, publication dates) is sourced from Europe PMC, which aggregates content from PubMed/MEDLINE, PubMed Central, and other providers under the U.S. National Library of Medicine (NLM/NCBI). NLM does not claim copyright on abstracts; the original journal publishers or authors may hold rights to the full articles. AI-generated summaries are derived only from the abstract, never the full text, and are always labeled as AI-generated.
Want more like this?
Browse more from the feed. A free account unlocks the full feed, saving and communities.
Back to the research feed