Cancer Cell Metabolism and the Warburg Effect

Flashcards summarizing key concepts from notes on cancer cell metabolism and the Warburg Effect.

What is the Warburg Effect in cancer cell metabolism?

Cancer cells prefer aerobic glycolysis even in the presence of oxygen, producing only 2 ATP per glucose, compared to 32 ATP from normal oxidative phosphorylation.

Why do cancer cells rely on aerobic glycolysis?

• Cancer cells rely on aerobic glycolysis due to the Warburg effect.

• This promotes rapid glucose import essential for quick growth, even in oxygen-rich environments.

• Aberrant mitochondria results in altered pyruvate processing and increased lactate production.

• This prevents ATP overproduction which facilitates survival and proliferation under stress.

• Aerobic glycolysis also produces metabolic intermediates for synthesis of macromolecules needed for cell growth.

How is the Warburg Effect used in cancer diagnostics?

The Warburg Effect is used in diagnostics by utilizing FDG (fluorodeoxyglucose) in PET scans, which accumulates in tumors due to high glucose uptake.

What is the role of Pyruvate Kinase M2 (PKM2) in cancer metabolism?

• PKM2 slows glycolysis by adopting a low-activity form that limits the final step (PEP → pyruvate)

• allowing upstream metabolites to be diverted into anabolic pathways.

• supporting the synthesis of nucleotides, lipids, and amino acids.

How do MYC and p53 influence cancer metabolism?

MYC increases glucose metabolism and enhances PKM2 expression, while p53 promotes oxidative phosphorylation and inhibits glycolysis.

Why is the metabolic shift beneficial for cancer cells?

• provides building blocks for rapid division

• regenerates NAD+

• adapts to hypoxic tumor environments.

What are some therapeutic strategies targeting cancer metabolism?

• GLUT1 inhibitors

• glycolysis inhibitors

• PKM2 inhibitors

• LDHA inhibitors

• methotrexate to block nucleotide biosynthesis.