EMT reversal in human cancer cells after IR knockdown in hyperinsulinemic mice

Abstract

Type 2 Diabetes (T2D) is associated with increased cancer risk and cancer-related mortality. Data herein show that we generated an immunodeficient hyperinsulinemic mouse by crossing the Rag1−/− mice, which have no mature B or T lymphocytes, with the MKR mouse model of T2D to generate the Rag1−/− (Rag/WT) and Rag1−/−/MKR+/+ (Rag/MKR) mice. The female Rag/MKR mice are insulin resistant and have significantly higher non-fasting plasma insulin levels compared to the Rag/WT controls. Therefore, we used these Rag/MKR mice to investigate the role of endogenous hyperinsulinemia on human cancer progression. In this study we show that hyperinsulinemia in the Rag/MKR mice increases the expression of mesenchymal transcription factors, TWIST1 and ZEB1, and increases the expression of the angiogenesis marker, vascular endothelial growth factor A (VEGFA). We also show that silencing the insulin receptor (IR) in the human LCC6 cancer cells leads to decreased tumor growth and metastases, suppression of mesenchymal markers Vimentin, SLUG, TWIST1, and ZEB1, suppression of angiogenesis markers, VEGFA and VEGFD, and re-expression of the epithelial marker, E-cadherin. The data in this paper demonstrate that IR knockdown in primary tumors partially reverses the growth promoting effects of hyperinsulinemia as well as highlighting the importance of the insulin receptor signaling pathway in cancer progression, and more specifically in epithelial-mesenchymal transition.

Discoidin domain receptor 1 modulates insulin receptor signaling and biological responses in breast cancer cells

“…IIGFs is especially relevant to Epithelial Mesenchymal Transition (EMT) [5] and other stem-like features [6], which play a key role in cancer development and recurrence. However, IGF-1R inhibitors have shown limited benefit in cancer when used as single therapy [7–10].…”

OP449 inhibits breast cancer growth without adverse metabolic effects

“…Here we present findings supporting an anti-neoplastic effect of OP449 on human MDA-MB-231 breast cancer xenografts and murine MVT-1 tumors in the Rag /MKR immunodeficient mouse model of hyperinsulinemia (Zelenko, et al 2016). Moreover, while breast tumor growth is inhibited, OP449 treatment was not associated with metabolic derangements.…”

“…The Rag1 −/− /MKR +/+ (Rag/MKR) mouse was generated by crossing the hyperinsulinemic MKR +/+ with the Rag1 knockout (Rag1 −/− ) mouse, which lacks mature T and B lymphocytes. Rag/MKR mice have a similar metabolic phenotype compared with MKR mice and have been previously described (Zelenko et al 2016). …”

“…The PI3K/Akt/mTOR pathway is the main signaling pathway that shows increased activation in tumors from MKR mice (Novosyadlyy et al 2010). We have previously generated an immunodeficient MKR mouse model, the Rag/MKR mouse, which has a similar metabolic phenotype compared with MKR mice (Zelenko et al 2016). In the current study we found that endogenous hyperinsulinemia enhanced the growth of human MDA-MB-231 breast cancer xenografts in an immunodeficient Rag/MKR mouse model, and that there was increased IR/IGF-1R phosphorylation in these tumors.…”

Hyperinsulinemia promotes aberrant histone acetylation in triple negative breast cancer

“…The immunodeficient hyperinsulinemic mice were 586 generated as previously described by crossing the recombination-activating gene 1 587 (Rag1) knockout mice with the muscle creatinine kinase promoter expressing dominant-588 negative Igf1r (MKR) mice (Zelenko et al, 2016). The metabolic phenotyping of the 589 Rag1 knockout (Rag1 -/-) / MKR mice and control Rag1 -/mice has been characterized 590 previously (Zelenko et al, 2016). Mice for this study were maintained on regular diet 591 (PicoLab Rodent Diet 20, 5053), with free access to water and a 12 hour light / dark 592 cycle.…”