Urinary proteome alterations in HER2 enriched breast cancer revealed by multipronged quantitative proteomics

Abstract

Globally, breast cancer is the second most common cancer among women. Although biomarker discoveries through various proteomic approaches of tissue and serum samples have been studied in breast cancer, urinary proteome alterations in breast cancer are least studied. Urine being a noninvasive biofluid and a significant source of proteins, it has the potential in early diagnosis of breast cancer. This study used complementary quantitative gel-based and gel-free proteomic approaches to find a panel of urinary protein markers that could discriminate HER2 enriched (HE) subtype breast cancer from the healthy controls. A total of 183 differentially expressed proteins were identified using three complementary approaches, namely 2D-DIGE, iTRAQ, and sequential window acquisition of all theoretical mass spectra. The differentially expressed proteins were subjected to various bioinformatics analyses for deciphering the biological context of these proteins using protein analysis through evolutionary relationships, database for annotation, visualization and integrated discovery, and STRING. Multivariate statistical analysis was undertaken to identify the set of most significant proteins, which could discriminate HE breast cancer from healthy controls. Immunoblotting and MRM-based validation in a separate cohort testified a panel of 21 proteins such as zinc-alpha2-glycoprotein, A2GL, retinol-binding protein 4, annexin A1, SAP3, SRC8, gelsolin, kininogen 1, CO9, clusterin, ceruloplasmin, and α1-antitrypsin could be a panel of candidate markers that could discriminate HE breast cancer from healthy controls.

Proteomics biomarkers for solid tumors: Current status and future prospects

“…Gajbhiye et al investigated urinary protein markers that could discriminate HER2‐positive breast cancer patients ( n = 24) from healthy individuals ( n = 24) using 2D‐DIGE, iTRAQ‐LC‐MS/MS, and SWATH . Using those three complementary approaches, 183 proteins were identified to be differentially expressed between the case and control groups.…”

“…As revealed by WB, the urinary levels of AZGP1, LRG1, ANXA1, SAP3, SRC8, and A1AG1 were upregulated in patients with HER2‐ positive breast cancer compared to healthy individuals, whereas A1AT, KNG1, GSN, CLUS urinary levels were decreased. In case of ANXA1, AZGP1 and A1AG1, their increased abundance was also confirmed by MRM …”

“…Similarly, IGFBP‐2 stimulates proliferation and inhibits apoptosis in cancer cells in general and is also frequently identified in increased levels in the body fluids of tumor‐bearing patients. Serum LRG1 has been classified as an “acute‐phase protein” involved in inflammatory response and was reported highly expressed in ovarian, breast and gastric cancer . CLUS is a novel regulator of TGF‐β signaling by modulating Smad2/3 proteins and was reported to be involved in many pathological processes including tumorigenesis .…”

Early urinary candidate biomarker discovery in a rat thioacetamide-induced liver fibrosis model

“…However, urine accumulates changes 55 of the body, which makes it a better early biomarker source [22,23] . Urinary proteomics has 56 become increasingly important in studies of quantitative changes in proteins resulting 57 from changes in disease states [24][25][26][27][28] ; moreover, numerous urinary protein biomarkers 58 have been reported in different diseases [29][30][31][32] . These findings suggest that urinary proteins 59 may serve as non-invasive biomarkers for diseases.…”

Early biomarker discovery in urine of Walker 256 subcutaneous rat model

“…A variety of malignant tumors consistently overexpressed NGAL with increased concentrations in urine, and NGAL was a potential biomarker for malignancy [41]. KNT1 was validated to be a urine marker of breast cancer [42]. Additionally, several proteins were reported to be associated with cancer.…”