Expression of mRNA MMP-7 and mRNA TIMP-1 in non-small cell lung cancer

Destruction of the extracellular matrix is a necessary precondition for metastasis and invasion of tumour cells. Metalloproteinases (MMPs) are involved in this process, matrilysin being one of them (MMP-7). The results of our pilot study with patients operated on for non-small cell lung carcinoma (NSCLC), with the assessment of MMP-7 and the tissue inhibitor of matrix metalloproteinase (TIMP-1), are presented here.

The group consisted of 34 patients who had been operated on in the course of 2005. Messenger RNA MMP- 7 and TIMP-1 were assessed in 20 cases (58%). Tissue samples were frozen to -70 degrees C, total RNA was subsequently isolated and a reverse transcription was performed from it. The quantitative assessment itself was performed using a real-time PCR method. The resulting expression level was determined as the expression ratio of the assessed gene and the housekeeping gene, glyceraldehyde-3-phosphate dehydrogenase (GAPDH).

A higher expression of mRNA MMP-7 was found in the NSCLC tissue than in non-tumourous lung tissue. On the other hand, a higher expression of mRNA TIMP-1 in the non-tumourous surrounding lung tissue was demonstrated. The expression of mRNA MMP-7 and TIMP-1 was higher in adenocarcinoma than in the epidermoid form of NSCLC.

The value of our results should not be overestimated since we had only a small group of patients and assessed only one of the whole range of metalloproteinases (MMP-7). We consider the assessment and ratio quantification of metallorpoteinases in normal lung and NSCLC to be the first step in a further application of these parameters.