Background: Accumulating data indicate that human epidermal growth factor receptor-2 (HER2)-positive breast cancer is a heterogeneous disease. We undertook a study to correlate lipid profiles with heterogeneous clinicopathological features of HER2-positive breast cancer.
Materials and methods: Histology-directed matrix-assisted laser desorption/ionization (MALDI)-mass spectrometry (MS) analyses were performed on 22 retrospective frozen tissue samples collected from patients with HER2-positive metastatic breast cancer, in order to correlate lipid profiles with clinicopathological characteristics. Additionally, a pair of tumor and adjacent normal tissue was profiled to identify cancer-associated changes in lipid profiles.
Results: Sphingomyelin 34:1, phosphatidylcholine (PC) 32:0, and PC 34:1, and PC 36:2 were overexpressed in HER2-positive breast cancer compared to adjacent normal tissue (HER2 signature). Lipid MALDI-MS profiles were different between Ki-67-high and Ki-67-low tumors. The proliferation signature (Ki-67-high vs. Ki-67-low) and the HER2 signature (cancer vs. normal) did not significantly overlap with each other.
Conclusion: For the first time to our knowledge, this study describes lipid profiles correlated with various clinicopathological characteristics of HER2-positive breast cancer. Lipid profiling might be helpful for the molecular characterization of this disease.
Keywords: HER2; MALDI; breast cancer; lipid; profiles.