The Difference of Expression of 18 Genes in Axillary Invasion and Vascular Invasion Compared to Control Samples in Breast Cancer.

BACKGROUND & OBJECTIVE: Recent studies from gene profiling have revealed some genes that are overexpressed in the epithelial-mesenchymal transition (EMT) process and are responsible for its initiation and activation resulting in tumor progression and metastasis. The present study aimed to assess the role of genes involved in the EMT process and the association of these genes with axillary lymph node and vascular invasion in breast cancer (BC) patients.

METHODS

In this case-control study, the tumor samples were initially extracted from 33 BC patients. The samples of 15 BC tissues without vascular and axillary invasion were also prepared from the biobank as a control group. RNAs from both tumor and control samples were extracted and stabilized. For assessing overexpression in tumor tissues of selected 18 genes, the real time technique was employed.

RESULTS

There was a significant increase in MMP-2 gene fold expression in tumor cells with vascular invasion regardless of axillary involvement compared to the control group (=0.0008) and also in the comparison of the control group with those with vascular invasion and not axillary lymph node involvement (=0.003). In addition, gene fold expression of tissue inhibitors of metalloproteinase-1(TIMP-1) was decreased in axillary involving tumor cells compared to control group (=0.045), and also in comparison with all samples that did not present any axillary lymph node involvements including the control group and the group with isolated vascular invasion (=0.012).

CONCLUSION

Overexpression of MMP-2 and under-expression of TIMP-1 were associated with more invasive behavior in breast tumor cells.