Dual Targeting of the Warburg Effect with a Glucose-Conjugated Lactate Dehydrogenase Inhibitor

Effective glucose diet: We report the development and activity of glucose-conjugated LDH-A inhibitors designed for dual targeting of the Warburg effect (elevated glucose uptake and glycolysis) in cancer cells. Glycoconjugation could be applied to inhibitors of many enzymes involved in glycolysis or tumor metabolism

A Small Molecule that Induces Intrinsic Pathway Apoptosis with Unparalleled Speed

Apoptosis is generally believed to be a process thatrequires several hours, in contrast to non-programmed forms of cell death that can occur in minutes. Our findings challenge the time-consuming nature of apoptosis as we describe the discovery and characterization of a small molecule, named Raptinal, which initiates intrinsic pathway caspase-dependent apoptosis within minutes in multiple cell lines. Comparison to a mechanistically diverse panel of apoptotic stimuli reveals that Raptinal-induced apoptosis proceeds with unparalleled speed. The rapid phenotype enabled identification of the criticalroles of mitochondrial voltage-dependent anion channel function, mitochondrial membrane potential/coupled respiration, and mitochondrial complex I, III, and IV function for apoptosis induction. Use of Raptinal in whole organisms demonstrates its utility for studying apoptosis invivo for a variety of applications. Overall, rapid inducers of apoptosis are powerful tools that will be used in a variety of settings to generate further insight into the apoptotic machinery. Palchaudhuri etal. describe the discovery of a small molecule called "Raptinal" that induces unusually rapid apoptotic cell death via the intrinsic pathway. Their work describes the utility of Raptinal as a tool for apoptosis induction relative to other available small molecules

Development and Mechanistic Characterization of Novel Small Molecules as Cancer Therapeutics

The discovery and development of novel small molecules as anti-cancer agents plays an integral role in the fight against cancer. Such efforts will lead to the development of the therapies of tomorrow. Potentially useful molecules may be discovered through cell-based toxicity screens, enzyme-based in vitro screens or developed from computational design against proteins of interest. The elucidation of the mechanism of action of small molecules discovered in cell-based screens remains a challenging endeavor. Whole genome transcript profiling and genome-wide shRNA screens are tools that have recently become available to the researcher and their use in aiding mechanism elucidation is reviewed in Chapter 1. Also presented herein is the development and investigation of the mechanism of action of several novel small molecules that exhibit anti-cancer activity. Genome-wide technologies are employed to characterize the mechanism of several of these molecules. Chapter 2 focuses on the mechanism of a rapid inducer of caspase-dependent apoptosis. Chapters 3 and 4 investigate novel triphenylmethyl containing anticancer agents and compare their mechanisms of action to known agents. The development of lactate dehydrogenase-A (LDH-A) inhibitors as a novel anticancer strategy is discussed in Chapter 5. In Chapter 6, the mode of action of anti-cancer quinones is described. And finally, the discovery of triazole-containing small molecules as tubulin-targeting agents is narrated in Chapter 7

A Small Molecule that Induces Intrinsic Pathway Apoptosis with Unparalleled Speed

Apoptosis is generally believed to be a process that requires several hours, in contrast to non-programmed forms of cell death that can occur in minutes. Our findings challenge the time-consuming nature of apoptosis as we describe the discovery and characterization of a small molecule, named Raptinal, which initiates intrinsic pathway caspase-dependent apoptosis within minutes in multiple cell lines. Comparison to a mechanistically diverse panel of apoptotic stimuli reveals that Raptinal-induced apoptosis proceeds with unparalleled speed. The rapid phenotype enabled identification of the critical roles of mitochondrial voltage-dependent anion channel function, mitochondrial membrane potential/coupled respiration, and mitochondrial complex I, III, and IV function for apoptosis induction. Use of Raptinal in whole organisms demonstrates its utility for studying apoptosis in vivo for a variety of applications. Overall, rapid inducers of apoptosis are powerful tools that will be used in a variety of settings to generate further insight into the apoptotic machinery

Non-genotoxic conditioning for hematopoietic stem cell transplantation using a hematopoietic-cell-specific internalizing immunotoxin

Hematopoietic stem cell transplantation (HSCT) offers curative therapy for patients with hemoglobinopathies, congenital immunodeficiencies, and other conditions, possibly including AIDS. Autologous HSCT using genetically corrected cells would avoid the risk of graft-versus-host disease (GVHD), but the genotoxicity of conditioning remains a substantial barrier to the development of this approach. Here we report an internalizing immunotoxin targeting the hematopoietic-cell-restricted CD45 receptor that effectively conditions immunocompetent mice. A single dose of the immunotoxin, CD45–saporin (SAP), enabled efficient (>90%) engraftment of donor cells and full correction of a sickle-cell anemia model. In contrast to irradiation, CD45–SAP completely avoided neutropenia and anemia, spared bone marrow and thymic niches, enabling rapid recovery of T and B cells, preserved anti-fungal immunity, and had minimal overall toxicity. This non-genotoxic conditioning method may provide an attractive alternative to current conditioning regimens for HSCT in the treatment of non-malignant blood diseases