Context: The insulin-like growth factor (IGF) and insulin receptors' (IR) axes play important roles in both breast cancer and diabetes mellitus.
Aim: We tend to explore the expression characteristics of proteins in IGF/IR axis in breast cancer with type 2 diabetes mellitus (T2DM).
Settings and design: We conducted a case-control investigation of T2DM and non-diabetes (n = 40, 1:1) in breast cancer patients.
Materials and methods: Some important molecules of IGF/IR axis were detected in breast cancer tissues by immunohistochemical staining. The multivariable analyses of the relationship of clinicopathological characters with the significant molecules were also detected.
Statistical analysis used: The results were statistically evaluated by Statistical Package for the Social Sciences (SPSS version 17.0) software. Chi-square test and logistic regression are used.
Results: Higher expression of IGF 1 receptor (IGF1R) was found in breast cancers of patients with T2DM, compared those without diabetes (P = 0.044). Negative expression of human epidermal growth factor receptor 2 (Her2) was found to be associated with higher expression of IGF1R in the breast cancers of patients with T2DM. There were no differences found in the expression of proteins of IGF-1, IGF-2, IGF-binding protein 3 (IGFBP3), IR, insulin receptor substrate (IRS)-1, IRS-2 and mammalian target of rapamycin (mTOR) between T2DM group and non-diabetes group.
Conclusion: Our study found that breast cancer with T2DM had a higher expression of IGF1R, and the higher IGF1R was associated with negative Her2 expression.