A ligand-based and enediyne-energized bispecific fusion protein targeting epidermal growth factor receptor and insulin-like growth factor-1 receptor shows potent antitumor efficacy against esophageal cancer

Abstract

Abstract. Recent studies have revealed that the epidermal growth factor receptor (EGFR) and insulin-like growth factor-1 receptor (IGF-1R) are overexpressed in various types of human tumors and are attractive targets for anticancer drugs. In the present study, the expression of EGFR and IGF-1R in esophageal squamous cell carcinoma (ESCC) and adjacent normal tissues in a tissue microarray was firstly detected by immunohistochemical staining. In addition, their co-overexpression was observed in 48 out of 75 (64%) patients. Based on the findings, the antitumor activity of an EGFR/IGF-1R bispecific and enediyne-energized fusion protein EGF-LDP-IGF-AE, which we constructed recently by fusing two ligands (EGF and IGF-1) with an enediyne antibiotic lidamycin (LDM), on ESCC were evaluated. Binding assay indicated that the EGF-LDP-IGF protein bound to esophageal cancer cells, and then internalized into the cytoplasm. In vitro, the enediyne-energized fusion protein EGF-LDP-IGF-AE exhibited extremely potent cytotoxicity to ESCC cells with IC 50 values between 10 -10 and 10 -15 mol/l. In vivo, EGF-LDP-IGF-AE also markedly suppressed the growth of human KYSE450 xenografts by 75.1% when administered at 0.3 mg/kg in a nude mouse model, and its efficacy was significantly higher than that of LDM (at maximum tolerated dosage) and mono-specific counterparts. In addition, EGF-LDP-IGF-AE arrested cell cycle progression and it concentration-dependently induced cell apoptosis as well as inhibited the activation of EGFR/IGF-1R and two major downstream signaling pathways (PI3K/AKT and RAS/MAPK). These data imply the potential clinical application of EGF-LDP-IGF-AE for ESCC patients with EGFR and/or IGF-1R overexpression. IntroductionThe morbidity and mortality of esophageal cancer rank the eighth and sixth among all malignant tumors worldwide (1). Esophageal cancer is classified into esophageal squamous cell carcinoma (ESCC) and adenocarcinoma (EAC) based on the histopathologic type. In Western countries, EAC represents the dominant subtype and the incidence has increased markedly over the past decades, whereas the northern regions of Henan Province, China, have the highest incidence of ESCC (2). Despite the great advances in early diagnosis and traditional treatment options (surgery, chemotherapy and radiotherapy), the prognosis of patients with advanced esophageal cancer remains poor with the 5-year survival rate ranging from 15 to 25% (3). During the past decade, the field of drug development has been transformed with the identification of and ability to direct treatment at specific molecular targets. The overexpression and aberrant function of epidermal growth factor receptor (EGFR) and insulin-like growth factor-1 receptor (IGF-1R) in a number of solid tumors including esophageal cancer, and the important roles in the development of tumors have provided a rationale for targeting the two receptors.EGFR/HER1 is a member of the ErbB receptor tyrosine kinase family, and there are three other members, HER2, HER3 and HER4, in this family...

Downregulation of miR‐100‐5p in cancer‐associated fibroblast‐derived exosomes facilitates lymphangiogenesis in esophageal squamous cell carcinoma

“…As a classical intracellular signaling pathway, the PI3K/AKT pathway is activated by insulin signaling and regulates cell growth, apoptosis, and metabolism 49,50 . Many studies have proved that inhibiting IGF1R and PI3K/AKT can effectively prevent the malignant biological behavior of ESCC, and improve the treatment sensitivity 51–53 . Furthermore, this pathway has also been implicated in the generation of blood vessels and lymphatic vessels in a variety of tumors 54,55 .…”

“… 49 , 50 Many studies have proved that inhibiting IGF1R and PI3K/AKT can effectively prevent the malignant biological behavior of ESCC, and improve the treatment sensitivity. 51 , 52 , 53 Furthermore, this pathway has also been implicated in the generation of blood vessels and lymphatic vessels in a variety of tumors. 54 , 55 To verify whether the IGF1R/PI3K/AKT pathway mediates the regulation of ESCC lymphangiogenesis by miR‐100‐5p in CAF‐derived exosomes, we detected IGF1R, PI3K, AKT, and p‐AKT expression in TLECs and tumors.…”

Effect of inhibiting ACAT‑1 expression on the growth and metastasis of Lewis lung carcinoma

“…ACAT-1 may increase cholesterol ester levels and elevate blood sugar in the body, resulting in insulin secretion which may in turn increase the activity of insulin-like growth factor (IGF). Increased IGF function may promote cell mitosis, thereby accelerating cell proliferation and promoting tumor growth (30–32). Studies have demonstrated that IGF is closely associated with lung cancer progression (33,34).…”

GH and IGF1 in cancer therapy resistance

“…Similarly, based on their highly consistent co-expression profile, the approach of dual inhibition of IGF1R and EGFR/HER2 was adopted and have shown significant success in multiple pre-clinical models of different cancer -viz. (i) a bi-specific (anti-IGF1R and -EGFR) antibody XGFR in pancreatic cancer (Schanzer et al 2016), (ii) IGF1R inhibitor linsitinib with EGFR inhibitors lapatinib or gefitinib in esophageal squamous cell carcinoma (Kang et al 2022), (iii) a ligand-based enediyne-energized bi-specific fusion protein (anti-IGF1R and -EGFR) in esophageal (Cao et al 2017) and non-smallcell lung cancer (Guo et al 2017), (iv) AVE1642 (anti-IGF1R mAb) and gefitinib in HCC (Desbois-Mouthon et al 2009), (v) ganitumab and panitumumab (anti-EGFR mAb) in advanced cancers (non-small-cell lung cancer and sarcoma) (Vlahovic et al 2018) Endocrine-Related Cancer e220414 and panitumumab in metastatic colorectal cancer (Van Cutsem et al 2014), to name a few. Interestingly, the antidiabetic 'wonder drug' metformin is reported to affect a downregulation of IGF1R and thereby enhance the efficacy of figitumumab (mAb against IGF1R) in smallcell lung cancer (Cao et al 2015) and non-small-cell lung cancer (Cao et al 2016).…”