Small molecules to regulate the GH/IGF1 axis by inhibiting the growth hormone receptor synthesis

Abstract

Growth hormone (GH) and insulin‐like growth factor‐1 (IGF1) play an important role in mammalian development, cell proliferation and lifespan. Especially in cases of tumor growth there is an urgent need to control the GH/IGF1 axis. In this study we screened a 38,480-compound library, and in two consecutive rounds of analogues selection, we identified active lead compounds based on the following criteria: inhibition the GH receptor (GHR) activity and its downstream effectors Jak2 and STAT5, and inhibition of growth of breast and colon cancer cells. The most active small molecule (BM001) inhibited both the GH/IGF1 axis and cell proliferation with an IC50 of 10‐30 nM of human cancer cells. BM001 depleted GHR in human lymphoblasts. In preclinical xenografted experiments, BM001 showed a strong decrease in tumor volume in mice transplanted with MDA‐MB‐231 breast cancer cells. Mechanistically, the drug acts on the synthesis of the GHR. Our findings open the possibility to inhibit the GH/IGF1 axis with a small molecule.

A novel antifolate suppresses growth of FPGS-deficient cells and overcomes methotrexate resistance

“…In a screen of compounds with potential antineoplastic activity (Van der Velden et al, 2022), we identified a 2,4-diaminopyrimidine-derivative (C1, also referred to as BM001 (Van der Velden et al, 2022)) that selectively inhibited growth of a subset of cancer cell lines (Supplementary Table 1). We noted that C1 shares structural features with non-classical antifolates like pyrimethamine (Figure 1A).…”

“…Here, we report on the characterization of C1, a novel polyglutamylation-independent antifolate. C1 has been studied as a pesticide (patent WO9820878A1), but recently regained interest for use in human subjects after showing potent inhibition of tumor growth and limited toxicity in a mouse model, where it was studied for potential effects on growth hormone signaling (Van der Velden et al, 2022). To our knowledge, our study is the first in-depth characterization of C1 as antifolate in human tissue-derived model systems, although a group of compounds with similarities to C1 has been studied in vitro using purified hDHFR (Algul et al, 2011).…”

WIP1 is a novel specific target for growth hormone action

“…Blocking GH signaling with BM001, a small molecule that inhibits GHR synthesis 52 ( Figure 6 A; Figure S6 A), also inhibited Src/AMPK phosphorylation ( Figures 6 B and 6C; Figures S6 B and S6C), subsequently inhibiting WIP1 and activating ATM phosphorylation ( Figure 6 D; Figure S6 D).

Figure 6 Blocking GH signaling inhibited GH-related WIP1 induction (A–D) Western blots of hNCC line #1 treated with (A) increasing doses of BM001 (GHR synthesis inhibitor) for 24 h; (B) 25 nM BM001 for 24 h followed by GH (500 ng/mL) for 30 min; (C) 25 nM BM001 for 24 h followed by GH (500 ng/mL) for 3 h; and (D) 25 nM BM001 for 1 h followed by GH (500 ng/mL) for an additional 24 h. (E) Colon tissue derived from 3-month-old female mice treated i.p.

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“…Etoposide, WIP1 inhibitor (GSK2830371), AMPK inhibitor (Compound C, CAS 866405-64-3) and Src inhibitor (dasatinib, BMS-354825) were reconstituted in DMSO at a stock concentration of 50 mM. The GHR synthesis inhibitor antibody BM001 52 was provided by Specs (Zoetermeer, The Netherlands) and reconstituted in DMSO at a stock concentration of 10 mM.…”

Ghrelin regulating liver activity and its potential effects on liver fibrosis and Echinococcosis

“…A deficiency of GH or STAT5 could cause major changes in fat distribution and mobilization, leading to the occurrence of acquired metabolic liver diseases ( Barclay et al., 2011 ). At the liver level, the Ghrelin/GH signaling pathway can regulate the expression and activity of IGF-I in the liver ( van der Velden et al., 2022 ), and IGF-I could reversely inhibit GH secretion and play an important role in balancing GH and insulin secretion ( Fang et al., 2022 ), but the mechanism of this negative feedback is unclear. IGF-I secreted by the liver is mainly combined into the IGF/insulin-like growth factor binding protein-3 (IGFBP-3) complex in circulating blood to be transported, and relying on the IGF-I receptor (IGF-IR), it plays an important role in metabolic regulation ( Adamek and Kasprzak, 2018 ).…”