Investigation of proteomic profiles in canine lymphoma using tandem mass tag-based quantitative proteomics approach

Specific tumor biomarkers are useful for the early diagnosis of cancer or can predict the recurrence of neoplastic disease in humans and animals. Lymphoma in dogs could be classified into B-, T-, and NK-cell origins. T-cell lymphoma has the worst prognosis with a shorter survival time and disease-free interval. This study aimed to identify the differential serum protein expressions of canine B- and T-cell lymphomas compared with healthy dogs using a tandem mass tag (TMT)-based quantitative proteomics.

Serum samples were collected from 20 untreated canine lymphomas (14 B-cells and 6 T-cells) and four healthy control dogs. Sera peptides from each sample were processed for TMT 10-plex tagging and analyzed using liquid chromatography-mass spectrometry (MS). Differential proteome profiling was then compared between lymphoma and control.

We discovered 20 elevated and 14 decreased serum proteins in the lymphoma group relative to the healthy group. Six candidate increased proteins in canine lymphomas were beta-actin cytoplasmic 1 (ACTB, p=0.04), haptoglobin (p=0.002), beta-2 microglobulin (aaaaaaaa2M, p=0.007), beta-2 glycoprotein 1 (APOH, p=0.03), metalloproteinase inhibitor 1 (TIMP-1, p=0.03), and CD44 antigen (p=0.02). When compared between B- and T-cell lymphomas, B-cell phenotypes had upregulated immunoglobulin (Ig) heavy chain V region GOM (p=0.02), clusterin (p=0.01), apolipoprotein C1 (APOC1, p=0.05), and plasminogen (p=0.02).

These findings were investigated quantitative serum proteomes between B- and T-cell lymphomas using TMT-based MS. ACTB, aaaaaaaa2M, APOH, TIMP-1, CD44 antigen, Ig heavy chain V region GOM, and APOC1 are novel candidate proteins and might serve as a lymphoma biomarker in dogs. However, evaluation with an increased sample size is needed to confirm their diagnostic and prognostic ability.