EGFR Expression as a Promising Druggable Target in Cancer: Comparison of Triple Negative Breast Tumors with Luminals

Introduction & Aim:EGFR gene (epidermal growth factor receptor) haskey roles in proliferation, angiogenesis and metastasis in malignant cells. Dysregulation of EGFR gene expression in breast malignancieswere reported in previous studies, although itʼs expressionhas shown differences among various subtypes of breast tumors and ethnic groups.Assessment of EGFR expression in malignancies is important due to the availability of anti-EGFR drugs that were approved by FDA such as Erlotinib and Gefitinib. The purpose of the present study is therefore a comparison of EGFR mRNA expression in luminal and triple negative tumors in Iranian breast cancer patients and the investigationof EGFRexpression association with main clinicopathologic characteristics.Methods:RT-PCRwere used to evaluate EGFR expression in the 27 luminal and 26 triple negative breast tumors, and 10 normal breast tissue samples.Results:The resultsof the current studyrevealed 12% of triple negative tumors have shown EGFR over expression, although none of the luminal tumors have shown EGFR overexpression.There was a high frequency of EGFR underexpression in luminal breast tumors (59.2%), unlike triple negative tumors (8%). Our results showed a significant positive correlation between EGFR expression and the size of luminal tumors(r=0.662) but not in triple negative tumors. The data revealed there are significant associations of high EGFR expression with estrogen and progesterone receptor negative and grade ІІІ in breast tumors.Conclusion:These findings suggest that aproportion of patients with triple negative tumors probably areeligible to receive the anti-EGFR therapies. It seems EGFR is a promising target in triple negative patients that have very poor prognosis with limited treatment options, although our findings require further investigation. Our results revealed EGFR expression likely has an interaction effect on tumor size and this effect depends on the tumor subtype.