Research article

Circulating levels of matrix metalloproteinase-9 (MMP-9), neutrophil gelatinase-associated lipocalin (NGAL) and their complex MMP-9/NGAL in breast cancer disease

Xeni Provatopoulou¹ , Antonia Gounaris¹ , Eleni Kalogera , Flora Zagouri² , Ioannis Flessas² , Evgenios Goussetis³ , Afroditi Nonni⁴ , Ioannis Papassotiriou⁵ and George Zografos²

¹Research Center, Hellenic Anticancer Institute, Athens, Greece

²Breast Unit, First Department of Propaedeutic Surgery, Hippokratio Hospital, University of Athens, Athens, Greece

³Stem Cell Transplant Unit, "Aghia Sophia" Children's Hospital, Athens, Greece

⁴First Department of Pathology, School of Medicine, University of Athens, Athens, Greece

⁵Department of Clinical Biochemistry, "Aghia Sophia" Children's Hospital, Athens, Greece

author email corresponding author email

BMC Cancer 2009, 9:390doi:10.1186/1471-2407-9-390

Published:	4 November 2009

Abstract

Background

Recent evidence suggests that neutrophil gelatinase-associated lipocalin (NGAL) expression is induced in many types of human cancer, while detection of its complex with matrix metalloproteinase-9 (MMP-9) is correlated with cancer disease status. We aim to evaluate the serum expression of MMP-9, NGAL and their complex (MMP-9/NGAL) during the diagnostic work-up of women with breast abnormalities and investigate their correlation with disease severity.

Methods

The study included 113 women with non-palpable breast lesions undergoing vacuum-assisted breast biopsy for histological diagnosis, and 30 healthy women, which served as controls. Expression levels of MMP-9, NGAL and their complex MMP-9/NGAL were determined in peripheral blood samples with immunoenzymatic assays.

Results

Women with invasive ductal carcinoma exhibited significantly increased levels of MMP-9, NGAL and MMP-9/NGAL compared to healthy controls (MMP-9: p < 0.003, NGAL: p < 0.008 MMP-9/NGAL: p < 0.01). Significant correlations were observed between MMP-9 and NGAL serum levels and breast disease severity score (r = 0.229, p < 0.006 and r = 0.206, p < 0.01, respectively), whereas a non-significant correlation was found for their complex. MMP-9, NGAL and their complex MMP-9/NGAL levels were not correlated with either Body Mass Index (BMI) or age of patients.

Conclusion

These findings suggest that the serum measurement of MMP-9 and NGAL may be useful in non-invasively monitoring breast cancer progression, while supporting their potential role as early biomarkers of breast disease status.