Breast cancer continues to be one of the main causes of morbidity and mortality globally
and was the leading cause of cancer death in women in Spain in 2020. Early diagnosis is one of
the most effective methods to lower the incidence and mortality rates of breast cancer. The human
metalloproteinases (MMP) mainly function as proteolytic enzymes degrading the extracellular matrix
and plays important roles in most steps of breast tumorigenesis. This retrospective cohort study
shows the immunohistochemical expression levels of MMP-1, MMP-2, MMP-3, and MMP-9 in
154 women with breast cancer and 42 women without tumor disease. The samples of breast tissue are
assessed using several tissue matrices (TMA). The percentages of staining (≤50%–>50%) and intensity
levels of staining (weak, moderate, or intense) are considered. The immunohistochemical expression
of the MMP-1-intensity (p = 0.043) and MMP-3 percentage (p = 0.018) and intensity, (p = 0.025) present
statistically significant associations with the variable group (control–case); therefore, expression in
the tumor tissue samples of these MMPs may be related to the development of breast cancer. The
relationships between these MMPs and some clinicopathological factors in breast cancer are also
evaluated but no correlation is found. These results suggest the use of MMP-1 and MMP-3 as
potential biomarkers of breast cancer diagnosis.Fundación Progreso Salud, grant number PI-0730-2013, and
by ISCIII, grant number PIE16/00045