Targeting the connection between deregulated insulin/igf axis and rage signalling in breast cancer patients

Background: Breast cancer mortality, associated with metastatic evolution, is increased in conditions of de-regulation of the Insulin/Insulin-like growth factor (IGF) pathway like prediabetes, Type-2 diabetes (T2DM) and obesity. The Receptor for Advanced Glycation End Products (RAGE) and its ligands mediate inflammatory responses involved in the pathogenesis and complications of hyperglycaemia, T2DM and obesity. In addition, the RAGE system has recently emerged as an orchestrator of autocrine and paracrine interactions occurring between cancer cells and the microenvironment toward malignant breast phenotypes.

Hypothesis: We have hypothesized that the RAGE system could be engaged in Insulin/IGF rich environment and coordinate a dysfunctional interaction between breast cancer cells and the inflammatory microenvironment, leading to disease progression. Our preliminary data show that RAGE expression correlates with genes identifying the Insulin/IGF pathway in breast cancer patients. In addition, we have found that RAGE levels are increased in breast cancer cells stimulated with high glucose, as well as with Insulin and IGF-I.

Aims: We aim to identify the role of the RAGE system in breast cancer progression, in conditions characterized by hyperglycaemia, T2DM and obesity. We wish to dissect the contribution of RAGE and its ligands in promoting a dysfunctional microenvironment
conducive to inflammation-driven metastatic progression. Thereafter, we plan to set a pharmacological combination strategy aimed at targeting the signalling connections between de-regulated Insulin/IGF signalling and the RAGE system, in order to halt disease progression in breast cancer patients affected by hyperglycaemia, obesity and T2DM.

Experimental Design: Genome editing strategies like CRISPR/CAS9 technology will be used to engineer breast cancer cells KO for IGF-IR, as well as to overexpress either the isoform A or B of the Insulin Receptor (IR). These cells will be investigated for their ability to induce RAGE-mediated proliferative and migratory effects in response to high glucose, Insulin, IGF-I and IGF-II. Genome-wide RNAsequencing and unbiased proteomic studies in breast cancer cells overexpressing RAGE will be used as an "omic" strategy to identify the main effectors orchestrating the biological responses to RAGE. Integrated bioinformatic analysis of gene expression datasets from large cohorts of breast cancer patients, and blood and breast tissue samples from pre-diabetic, T2DM and obese breast cancer patients will be used to validate the role of the RAGE system in metastatic progression. Cancer-Associated Fibroblasts (CAFs), adipocytes and macrophages will be used to shape the tumor microenvironment and dissect the paracrine interactions involving the Insulin/IGF system and the RAGE signaling in inflammation, immune evasion and metastasis. In vivo models, including zebrafish xenografts and Patient-derived xenografts (PDX), will be used to evaluate the impact of the RAGE system through the Insulin/IGF pathway in triggering breast tumor progression in pre-diabetes, T2DM and obesity.

Expected Results: We expect to identify and pharmacologically target unexplored signalling aberrations between the Insulin/IGF pathway and the RAGE system in order to halt metastatic progression in specific sub-populations of breast cancer patients.

Impact On Cancer: The study will set a pharmacological platform for a better clinical management of breast cancer patients affected by metabolic dysfunctions like pre-diabetes, T2DM and obesity.