Human neutrophil peptides 1–3 as gastric cancer tissue markers measured by MALDI-imaging mass spectrometry: Implications for infiltrated neutrophils as a tumor target

Article type: Research Article

Authors: Cheng, Chun-Chia^; | Chang, Jungshan^{; ; ;} | Chen, Ling-Yun | Ho, Ai-Sheng | Huang, Ker-Jer | Lee, Shui-Cheng | Mai, Fu-Der^{; ;} | Chang, Chun-Chao

Affiliations: Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Taipei, Taiwan | Institute of Nuclear Energy Research, Atomic Energy Council, Taoyuan, Taiwan | Department of Biochemistry, School of Medicine, Taipei Medical University, Taipei, Taiwan | Biomedical Mass Imaging Research Center, Taipei Medical University, Taipei, Taiwan | Neuroscience Research Center, Taipei Medical University Hospital, Taipei, Taiwan | Research Center for Biomedical Implants and Microsurgery Devices, Taipei Medical University, Taipei, Taiwan | Institute of Biochemistry and Biotechnology, Chung Shan Medical University, Taichung, Taiwan | Division of Gastroenterology, Cheng Hsin General Hospital, Taipei, Taiwan | Chung-Shan Institute of Science & Technology Armaments Bureau, Taoyuan, Taiwan | Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University Hospital, Taipei, Taiwan

Note: [] Corresponding author: Chun-Chao Chang, Division of Gastroenterology, Taipei Medical University Hospital, 250, Wu Hsing Street, Taipei 110, Taiwan. Tel.: +886 2 27372181 ext. 3903; Fax: +886 2 27363051; E-mail: chunchao@tmu.edu.tw

Abstract: Objective: Human neutrophil peptides (HNPs) -1, -2 and -3 are significantly upregulated and were reported as biomarkers in gastric cancer (GC). However, the tissue location and function of HNPs 1-3 are still unclear in GC, and the spatial distribution of the triad needs to be disclosed. The aims of this study were to investigate the distribution and relationships among HNPs-1, -2 and -3, and assess whether infiltrated neutrophils accumulate in gastric tumor. Methods: In this study, paired samples (n=33) of the GC tissues and adjacent normal tissues from the same patients were obtained from surgery. Expression of HNPs 1-3 were detected by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). The distributions of the HNPs 1-3 in GC tissues were investigated. After verification of HNPs-1 by immunohistochemistry, infiltrated neutrophils were also detected. Then, an in vitro assay was used to observe the binding capacity and measure the cytotoxic effect of HNPs-1 against AGS cells. Results: Comparing to neighboring normal tissue, expressional level of HNPs 1-3 were significantly higher and their distributions overlapped in cancerous tissues of GC patients with high abundance in the lamina propria, whereas HNPs-1 was identified as the highest major peak. Moreover, HNPs-1, -2 and -3 correlated with each other. Besides, we also observed that increased infiltrated neutrophils accumulating in GC tissues, indicating that a strong positive correlation between HNPs 1-3 and infiltrated neutrophils. In addition, the further investigated demonstrated that the major peptide, HNPs-1, was statistically increased with the advance of tumor development from the early to advanced stage of GC (p< 0.05). Moreover, we also noticed that HNPs-1 with a great binding capacity to GC AGS cells in vitro can inhibit tumor cell growth. Conclusions: Our results suggest that neutrophil secreted peptides, HNPs 1-3, increased in the GC tissues and could be used as potential biomarkers detected using MALDI-TOF MS, implying that elevated neutrophils may be used as a tumor target for tumor treatment. The binding capacity of HNPs-1 with GC cells implies that tracking molecules conjugated with HNPs-1 could be applied as a specific probe for GC diagnoses.

Keywords: Gastric cancer, human neutrophil peptides 1–3, MALDI-TOF MS, biomarker

DOI: 10.3233/DMA-2012-0857

Journal: Disease Markers, vol. 32, no. 1, pp. 21-31, 2012