Supplementary Material for: Expression of Insulin-like Growth Factor Type 1 Receptor is Linked to Inflammation in Adamantinomatous Craniopharyngioma

Introduction Insulin-like growth factor type 1 receptor (IGF1R) is overexpressed in various malignant tumors, which relates to their transformation and recurrence. Craniopharyngioma is a benign tumor with malignant results, often accompanied by a severe inflammatory reaction. However, the relationship between IGF1R expression and the inflammatory response of craniopharyngioma is unclear. Methods We enrolled 85 patients with adamantinomatous craniopharyngioma (ACP) in a study to explore the relationship between IGF1R expression and clinical features of this disease. Results Patients in the IGF1R high expression group had a significantly higher incidence of hypopituitarism, higher recurrence rate and lower progression-free survival. Beta-catenin can further regulate expression of the stem cell marker, CD44, by regulating IGF1R. Using immunofluorescence, we found that tumor stem cell–like cells did not express phosphorylated (p)-ERK, although p-ERK activation was evident in the surrounding cells. Picropodophyllin, a specific inhibitor of IGF1R, increased the expression of p-ERK protein, and decreased the transcription level of interleukin-6. Conclusions High expression of IGF1R might promote inflammation of ACP, which might be an unfavorable factor for pituitary function and prognosis. The high expression of IGF1R in tumor cell stem-like cells might inhibit the expression of p-ERK and promote the generation of inflammatory factors. Insulin-like growth factor type 1 receptor plays a stemness maintenance role in ACP and regulates the production of inflammatory factors through a p-ERK pathway, which suggests that targeting IGF1R and p-ERK might provide a new direction for alleviating tumor inflammation.