BACKGROUND AND OBJECTIVE: Breast cancer is a major cause of death in women, worldwide. Cytotoxic drugs may lead to various adverse side-effects in patients. Helicobacter pylori neutrophil-activating protein (HP-NAP) is one of the most important proteins, produced by helicobacter pylori. The purpose of this study was to investigate the expression of VEGF and MMP-9 genes, caused by HP-NAP treatment in a breast cancer model.

METHODS: In this experimental study, 18 female BALB/c mice, aged 6-8 weeks (19-23 g), were used. The mice were allocated to three groups: test group (treated with recombinant HP-NAP), positive control group (treated with an anti-cancer drug called trastuzumab), and negative control group (receiving phosphate-buffered saline). Expression and purification of HP-NAP were performed using nickel-resin affinity chromatography (Qiagen). The mice with breast tumors were treated with HP-NAP. MMP-9 and VEGF gene expression was measured using real-time polymerase chain reaction (PCR).

FINDINGS: Protein expression was confirmed, using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The analysis showed the expression of a 20,000 dalton protein. Moreover, MMP-9 and VEGF gene expression decreased more significantly in the test group (due to treatment with HP-NAP), compared to the negative control group. The reduced expression in the test group was almost a quarter of the expression in the control group (p<0.01).

CONCLUSION: The results showed that HP-NAP can reduce the expression of genes involved in metastasis in a mouse model of breast cancer. Therefore, this protein can be exploited for future therapeutic strategies in cancer treatment.