Immunoassays for Enzyme and Inhibitors Predict Breast Cancer

Immunoenzymatic assays have been used to detect serum concentrations of matrix metalloproteinases (MMPs) and their tissue inhibitors in patients with breast cancer.

Serum levels of MMP-2, family of zinc-dependent endopeptidases and the endogenous inhibitors of MMPs, the tissue inhibitors of metalloproteinases (TIMPs) can be measured either by profiling kits and enzyme linked immunosorbent assays (ELISA).

A study carried out at the University of Athens, (Athens, Greece), examined the serum concentration of the enzymes and inhibitors from a cohort of women with nonpalpable breast lesions who were followed for 24 months. Serum MMP-2 concentrations were measured using Fluorokine MultiAnalyte Profiling kits in a Luminex Bioanalyzer (Luminex Corp, TX, USA). Levels of the inhibitors TIMP-1 and TIMP-2 and other tumor markers were assessed using ELISA methods.

The scientists assessed serum concentrations of MMP1, MMP-2, TIMP-1, and TIMP-2 in atypical ductal hyperplasia (ADH), lobular neoplasia (LN), ductal carcinoma in situ (DCIS) and invasive ductal carcinoma (IDC) specifically in nonpalpable breast lesions found after mammography. The serum TIMPs and other tumor markers were assessed by ELISA methods from R&D Systems, (Minneapolis, MN, USA), and IDL Biotech AB, (Bromma, Sweden).

Serum TIMP-2 concentrations were positively associated with the severity of the lesion. Conversely, MMP-2 levels were marginally negatively associated with severity; as evident, the MMP-2/TIMP-2 ratio significantly decreased along with severity. No significant associations were demonstrated between the other biomarkers tested and breast cancer carcinogenesis. The MMP-2 serum levels and the MMP-2/TIMP-2 ratio were significantly higher in the LN subgroup compared with the ADH subgroup.

The authors concluded that TIMP-2 was associated with more severe diagnosis in nonpalpable lesions and that the MMP-2/TIMP-2 ratio may exhibit meaningful changes along with progression of lesions. Extracellular cell matrix remodeling in ductal and lobular lesions appears to follow distinct patterns. The study has been available online since December 3, 2010, in the journal Clinica Chimica Acta.

Related Links:
University of Athens
Luminex Corp.
R&D Systems
IDL Biotech AB