Finding Chinks in the Armor: Cancer’s Need for Metabolites

Illustration of energy metablism in cell.Cancer has been studied for decades by scientists trying to find a vulnerability to exploit and testing compounds to develop as potential drugs. As the “Emperor of All Maladies”, cancer has proven itself to be a wily beast with many varieties of genetic mutations for eluding cellular control, tireless in its ability to divide and spread. In the end, a cancer cell is still a cell and subject to its environment even though cancer does not play by the same rules as the normal cells that exist around it. To be able to grow, a cell needs access to metabolites, molecules needed for building the materials and machinery needed by the cell to function and divide. These requirements also offer potential pathways to target for halting cancer growth and spread.

All cells use glucose to generate ATP, but normal and cancer cells differ in how glucose is converted to ATP. Most cells use glucose in oxidative phosphorylation, but cancer cells use aerobic glycolysis, converting glucose to lactate without oxygen. This Warburg effect (glucose converted to lactate) is a hallmark of cancer cells as they take up glucose at a much higher rate than normal cells. Blocking glucose uptake is one way to target cancer cells. While 2-deoxyglucose (2DG) has been shown to slow glucose uptake in vitro, the compound proved toxic in clinical trials and lower dosages do not seem to be an effective treatment against cancer. While not an ideal drug target, glucose uptake has been helpful in monitoring cancer response to therapies via fluorodeoxyglucose positron emission tomography (FDG-PET). Continue reading

NAD: A Renaissance Molecule and its Role in Cell Health

Promega NAD/NADH-Glo system and how to prepare samples for  identification of NAD or NADH.

Promega NAD/NADH-Glo system and how to prepare samples for identification of NAD or NADH.

NAD is a pyridine nucleotide. It provides the oxidation and reduction power for generation of ATP by mitochondria. For many years it was believed that the primary function of NAD/NADH in cells was to harness and transfer energy  from glucose, fatty and amino acids through pathways like glycolysis, beta-oxidation and the citric acid cycle.

Today, however, NAD is recognized as an important cell signaling molecule and substrate. The many regulatory pathways now known to use NAD+ in signaling include multiple aspects of cellular homeostasis, energy metabolism, lifespan regulation, apoptosis, DNA repair and telomere maintenance.

This resurrection of NAD importance is due in no small part to the discovery of NAD-using enzymes, especially the sirtuins. Continue reading

Measuring Changing Metabolism in Cancer Cells

Because of the central role of energy metabolism in health and disease, and its effect on other cellular processes, assays to monitor changes in cellular metabolic state have wide application in both basic research and drug discovery. In the Webinar “Tools for Cell Metabolism: Bioluminescent NAD(P)/NAD(P)H-Glo™ Assays” Jolanta Vidurigiene, a Senior Research Scientist at Promega, introduces three new metabolism assays for measuring oxidized and reduced forms of NAD and NADP.

In this webinar, Jolanta provides background information on why it is important to be able to accurately measure metabolites such as NAD/NADH and NADP/NADPH. She outlines the roles of each, and highlights some of the challenges involved in developing assays that can accurately measure these metabolites. She discusses key considerations for successful NAD(P)/NAD(P)H assays and provides examples of how to use these assays to measure either total (both oxidized and reduced) forms of NAD and NADP, or to measure oxidized and reduced forms individually in a single assay plate.

NAD(P)H-Glo™ Assay Mechanism

NAD(P)H-Glo™ Assay Mechanism

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