Purpose: Matrix metalloproteinases (MMPs) are implicated in cancer cells invasion and metastasis processes and have been investigated as potential cancer biomarkers. In this study MMP-9 gene expression and MMP-9 -1562 C/T polymorphism in breast and non-small cell lung cancer patients' blood and tumor samples and its correlation with clinicopathological parameters were investigated.
Material/methods: MMP-9 gene expression was assessed by reverse transcription - polymerase chain reaction method in 108 cancer patients' blood and tumor samples. MMP-9 -1562 C/T polymorphism was determined by the polymerase chain reaction - based restriction fragment length polymorphism method.
Results: Significant relationship of MMP-9 gene expression and tumor differentiation grade was found only between groups with G1 and G3 breast tumors. Low survival rates were identified among positive MMP-9 expression in blood and ductal carcinoma of the breast (p=0.01) and negative progesterone receptor reaction (p=0.04). Significant differences in the distribution among genotypes were found between groups with stage I and stages III/IV (p=0.005) as well as between groups with lymph node status N0 and N1 (p<0.001). Breast cancer patients with tumor differentiation grade G3 and identified CC variant had a longer survival time (p=0.014). Shorter survival time was found among positive MMP-9 expression in tumor and stage I non-small cell lung cancer patients with negative lymph node (p=0.012) and squamous cell carcinoma (p=0.019).
Conclusions: Expression of MMP-9 in blood and tumor together indicates worse prognosis for breast cancer patients.