The IGF2/IR/IGF1R Pathway in Tumor Cells and Myofibroblasts Mediates Resistance to EGFR Inhibition in Cholangiocarcinoma

Abstract

Cholangiocarcinoma (CCA) is a desmoplastic tumor of the biliary tree in which epidermal growth factor receptor (EGFR) is overexpressed and contributes to cancer progression. Although EGFR has been envisaged as a target for therapy, treatment with tyrosine kinase inhibitors (TKI) such as erlotinib did not provide therapeutic benefit in patients with CCA, emphasizing the need to investigate resistance mechanisms against EGFR inhibition. Resistant CCA cells to EGFR inhibition were obtained upon long-time exposure of cells with erlotinib. Cell signaling, viability, migration, and spheroid growth were determined , and tumor growth was evaluated in CCA xenograft models. Erlotinib-resistant CCA cells displayed metastasis-associated signatures that correlated with a marked change in cell plasticity associated with an epithelial-mesenchymal transition (EMT) and a cancer stem cell (CSC)-like phenotype. Resistant cells exhibited an upregulation of insulin receptor (IR) and insulin-like growth factor (IGF) 1 receptor (IGF1R), along with an increase in IGF2 expression. IR/IGF1R inhibition reduced EMT and CSC-like traits in resistant cells. , tumors developed from resistant CCA cells were larger and exhibited a more prominent stromal compartment, enriched in cancer-associated fibroblasts (CAF). Pharmacological coinhibition of EGFR and IR/IGF1R reduced tumor growth and stromal compartment in resistant tumors. Modeling of CCA-CAF crosstalk showed that IGF2 expressed by fibroblasts boosted IR/IGF1R signaling in resistant cells. Furthermore, IR/IGF1R signaling positively regulated fibroblast proliferation and activation. To escape EGFR-TKI treatment, CCA tumor cells develop an adaptive mechanism by undergoing an IR/IGF1R-dependent phenotypic switch, involving a contribution of stromal cells. .

CD44 is overexpressed and correlated with tumor progression in gallbladder cancer

“…CSCs, a small part of cells, are present in heterogeneous tumors, and play a critical role in the initiation and progression of cancer and exhibition of strong chemoresistance to conventional chemotherapeutic drug treatment. 31 – 35 For these reasons, understanding the mechanism by which cancer cells enhance stemness may further facilitate cancer therapies. Yadav et al investigated germ line variants in CSC gene variants, and confirmed the essential role of CSCs in GBC susceptibility, prognosis and survival outcomes.…”

Cold-Atmospheric Plasma Induces Tumor Cell Death in Preclinical In Vivo and In Vitro Models of Human Cholangiocarcinoma

“…Results were analyzed using Kaluza analysis software (Beckman-Coulter). Immunofluorescence assays were performed as previously described [44]. Primary antibodies are provided in Table 1.…”

Neuroendocrine Changes in Cholangiocarcinoma Growth

“…Tyrosine kinase inhibitors, such as erlotinib, inhibit EGFR activation and have anti-cancer effects, although CCA tumors often have resistance to EGFR inhibitors [62]. Vaquero et al generated erlotinib-resistant CCA cells by escalating exposure to erlotinib from 1 to 20 µM and found that resistant CCA lines, including Mz-ChA-1, HuCCT1, and SK-ChA-1 cells, expressed higher levels of IGF-2 and IGF-1R as well as insulin receptor (IR) [63]. IR/IGF-1R inhibitor, linsitinib, decreased tumor volumes in xenograft mice with erlotinib-resistant CCA tumors [63].…”

“…Vaquero et al generated erlotinib-resistant CCA cells by escalating exposure to erlotinib from 1 to 20 µM and found that resistant CCA lines, including Mz-ChA-1, HuCCT1, and SK-ChA-1 cells, expressed higher levels of IGF-2 and IGF-1R as well as insulin receptor (IR) [63]. IR/IGF-1R inhibitor, linsitinib, decreased tumor volumes in xenograft mice with erlotinib-resistant CCA tumors [63]. A study analyzing serum and bile samples of 29 patients with extrahepatic CCA, 19 patients with pancreatic cancer, and 25 patients with benign biliary abnormalities found that CCA patients have significantly elevated levels of IGF-1 in bile compared to other patient groups but not in serum [64].…”