FAZ-3532

The passive transport of glucose and related hexoses in human cells is facilitated by members of the glucose transporter family (GLUT, SLC2 gene family). GLUT3 is a high-affinity glucose transporter primarily responsible for glucose entry in neurons. Changes in its expression have been implicated in neurodegenerative diseases and cancer. GLUT3 inhibitors can provide new ways to probe the pathophysiological role of GLUT3 and tackle GLUT3-dependent cancers. Through in silico screening of an ~ 8 million compounds library against the inward- and outward-facing models of GLUT3, we selected ~ 200 ligand candidates. These were tested for in vivo inhibition of GLUT3 expressed in hexose transporter-deficient yeast cells, resulting in six new GLUT3 inhibitors. Examining their specificity for GLUT1-5 revealed that the most potent GLUT3 inhibitor (G3iA, IC50 ~ 7 µM) was most selective for GLUT3, inhibiting less strongly only GLUT2 (IC50 ~ 29 µM). None of the GLUT3 inhibitors affected GLUT5, three inhibited GLUT1 with equal or twofold lower potency, and four showed comparable or two- to fivefold better inhibition of GLUT4. G3iD was a pan-Class 1 GLUT inhibitor with the highest preference for GLUT4 (IC50 ~ 3.9 µM). Given the prevalence of GLUT1 and GLUT3 overexpression in many cancers and multiple myeloma’s reliance on GLUT4, these GLUT3 inhibitors may discriminately hinder glucose entry into various cancer cells, promising novel therapeutic avenues in oncology.

Cytoplasmic stress granules (SG) assemble in response to stress-induced translational arrest and are key signaling hubs orchestrating cell fate and regulating various physiological and pathological processes. However, the role of SG formation in the progression of allergic diseases is incompletely understood. Here, by analyzing the nasal tissues of allergic rhinitis (AR) mouse models and AR patients, we find that SGs assemble specifically in the macrophages within the nasal mucosa and promote AR progression by restraining the efferocytotic ability of macrophages, ultimately resulting in reduced Mres generation and IL-10 production. Mechanistically, intracellular m7G-modified Lrp1 mRNA, encoding for a typical efferocytosis receptor, is transported by the m7G reader QKI7 into stress-induced SGs, where Lrp1 mRNA is sequestered away from the translation machinery, ultimately resulting in reduced macrophage efferocytosis. Therefore, SG assembly impairs macrophage efferocytosis and aggravates AR, and the inhibition of SGs bears considerable potential in the targeted therapy.