Before Sidney Farber published his seminal paper in 1948 in The New England Journal of Medicine describing anti-folate-induced remissions 1 , childhood acute lymphocytic leukaemia (ALL) was universally fatal. Thirty years before this article was published, Otto Warburg's determination to conquer cancer led him to discover that many tumours used aerobic glycolysis (also known as the Warburg effect) to convert almost all glucose to lactate even in the presence of oxygen 2 . Aerobic glycolysis, however, has never been successfully exploited clinically, particularly as the use of 2-deoxyglucose, which inhibits glycolysis, was proved to have undesirable side effects and limited efficacy in humans 3 . Farber noted the clinical 'accelerated phenomenon' among 11 children treated with an active form of folate, pteroyltriglutamic acid, which was thought to have broad anticancer activity, and thus sought folate antagonists as therapeutic agents. Working with chemist Yellapragada Subbarow, the anti-folate aminopterin was synthesized, and Farber was able to induce remissions in children with ALL, thus providing the foundation for cancer chemotherapy 4 . Today, another folate antagonist, methotrexate, is still used in the multi-chemotherapy treatment of childhood ALL and, used together with l-asparaginase, induces a remarkable 90% cure rate. Indeed, many anti-metabolite drugs, particularly those targeting nucleotide metabolism, have been approved and used in the clinic (Table 1). The recent approval of drugs that target mutant isocitrate dehydrogenases in acute myeloid leukaemias (AMLs) (Table 1) provides a milestone in targeting cancer metabolism with precision and establishes that metabolic therapy can be highly effective.Warburg's and Farber's ideas were conceptually displaced in the 1980s as oncogenes and tumour suppressors became recognized as targets in human cancer treatments. Molecular biology took centre stage, and the drive to target oncogenes began with vigour, resulting in many effective anticancer kinase drugs that displaced interest in targeting metabolism. However, the links between oncogenes, tumour suppressors and metabolism began to emerge in the 1990s, ushering in a resurgence of interest in cancer metabolism [5][6][7] . More recently, the success of immunotherapy underscores the importance of non-cancer-cell autonomous components of the tumour immune microenvironment (TIME) [8][9][10] , which is a neoplastic hub of metabolically active cells comprising tumour cells, immune cells, stromal cells and blood and lymph vessel cells, all of which are involved in tumour growth. In this regard, targeting cancer metabolism must be based on a thorough understanding of how inhibiting specific metabolic pathways affects the TIME cells, which can either dampen or promote tumour progression. In this Review, we cover the fundamentals of cancer metabolism and focus on recent small-molecule drug discovery efforts to target cancer.

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Non-peptide peptidomimetics of the peptide hormone somatostatin (SRIF) were designed and synthesized, utilizing fl-D-glUCOSe as a novel scaffolding. Such compounds resemble conventional peptide analogs in that they retain critical amino acid side chains but differ in that they are devoid of both the peptide backbone and amide surrogates. Structure-activity relationships resulting from systematic deletion or modification of the side chains of 4a were consistent with expectations, with the exception that analogs 8a and 8b, lacking an indole side chain, bound to the SRIF receptor. A possible explanation for this unexpected result and its potential implications are discussed. Unexpectedly we also found that the primary amino group of Lys9 is not required for SRIF receptor binding or activation. Taken together, the results reported herein, and those described elsewhere,lJ support the validity of the concept of non-peptide scaffolding and also demonstrate that non-peptidal peptidomimetics can provide unexpected biological information not previously available from natural ligands or their peptidal analogs.

Dysfunction of excitatory amino acid transporters (EAATs) has been implicated in the pathogenesis of various neurological disorders, such as stroke, brain trauma, epilepsy, and neurodegenerative diseases, among others. EAAT2 is the main subtype responsible for glutamate clearance in the brain, having a key role in regulating transmission and preventing excitotoxicity. Therefore, compounds that increase the expression or activity of EAAT2 have therapeutic potential for neuroprotection. Previous studies identified molecular determinants for EAAT2 transport stimulation in a structural domain that lies at the interface of the rigid trimerization domain and the central substrate binding transport domain. In this work, a hybrid structure based approach was applied, based on this molecular domain, to create a high-resolution pharmacophore. Subsequently, virtual screening of a library of small molecules was performed, identifying 10 hit molecules that interact at the proposed domain. Among these, three compounds were determined to be activators, four were inhibitors, and three had no effect on EAAT2-mediated transport in vitro. Further characterization of the two best ranking EAAT2 activators for efficacy, potency, and selectivity for glutamate over monoamine transporters subtypes and NMDA receptors and for efficacy in cultured astrocytes is demonstrated. Mutagenesis studies suggest that the EAAT2 activators interact with residues forming the interface between the trimerization and transport domains. These compounds enhance the glutamate translocation rate, with no effect on substrate interaction, suggesting an allosteric mechanism. The identification of these novel positive allosteric modulators of EAAT2 offers an innovative approach for the development of therapies based on glutamate transport enhancement.