12 cancer metabolism

Question 1

What is the definition of metabolism?

Answer 1

The chemical processes that occur within a living organism to maintain life.

Question 2

How does metabolism reflect cell phenotype?

Answer 2

: It provides insight into cellular function, energy use, and biosynthetic activity.

Question 3

Why do cancer cells have increased metabolic demands?

Answer 3

: They require more energy (ATP), biosynthetics (macromolecules), and redox buffering to support uncontrolled growth.

Question 4

What are the stages of tumour development and progression?

Answer 4

Hyperplasia → Adenoma → Adenocarcinoma.

Question 5

What did Freund discover in 1887 about cancer metabolism?

Answer 5

Blood cancers can be killed by glucose deprivation.

Question 6

What was Müller’s contribution to cancer metabolism in 1890?

Answer 6

He observed changes in the metabolic composition of cancer patient urine.

Question 7

What did Warburg propose about cancer metabolism in 1926?

Answer 7

Cancer cells exhibit increased glycolysis even in the presence of oxygen.

Question 8

Who is considered the “Godfather of Cancer Glycolysis”?

Answer 8

Otto Warburg.

Question 9

What is the Warburg Hypothesis?

Answer 9

Cancer cells have damaged respiration and ferment glucose excessively.

Question 10

What is the Warburg Effect?

Answer 10

Cancer cells rely on glycolysis even in the presence of oxygen, leading to increased lactate production.

Question 11

How does ATP production differ between normal and cancer cells?

Answer 11

Normal cells: 34 ATP via OxPhos + 2 ATP via glycolysis.
Cancer cells: 2 ATP via glycolysis with increased glucose flux.

Question 12

What imaging technique is used based on Warburg’s principles?

Answer 12

18F-fluorodeoxyglucose PET/CT.

Question 13

Why does FDG-PET work for cancer detection?

Answer 13

Cancer cells take up more glucose, and FDG accumulates without being metabolised.

Question 14

How does Ras activation affect cancer metabolism?

Answer 14

It upregulates glucose uptake and glycolysis via PI3K/Akt signalling.

Question 15

What happens when the VHL gene is lost in kidney cancer?

Answer 15

HIF signalling is activated, leading to widespread metabolic remodelling.

Question 16

What is the function of the Pentose Phosphate Pathway in cancer?

Answer 16

Produces NADPH and ribose-5-phosphate for nucleotide biosynthesis.

Question 17

How does glutamine metabolism support cancer cell growth?

Answer 17

Provides glutamate and α-ketoglutarate to fuel the TCA cycle.

Question 18

What is the Hexosamine Pathway used for?

Answer 18

Produces UDP-GlcNAc for protein modification.

Question 19

What is the structure of mitochondrial DNA?

Answer 19

A covalently-closed circular molecule located in the mitochondrial matrix.

Question 20

How many protein-coding genes are in mtDNA?

Answer 20

13, all involved in oxidative phosphorylation (OXPHOS).

Question 21

How do mtDNA mutations affect colorectal cancer?

Answer 21

They are enriched during adenoma-to-carcinoma progression and impact OXPHOS function.

Question 22

How can mtDNA mutations alter cancer metabolism?

Answer 22

They upregulate serine synthesis, one-carbon metabolism, and amino acid transporter expression.

Question 23

What is a key method to study cancer metabolomics?

Answer 23

Nuclear Magnetic Resonance (NMR) Spectroscopy.

Question 24

What is Mass Spectrometry (MS) used for in cancer metabolism?

Answer 24

Detects metabolites based on their mass-to-charge ratio.

Question 25

Q: How is metabolic pathway mapping performed in vivo?

Answer 25

Using radiolabelled isotopes like 13C-labelled glucose or glutamine.

Question 26

Q: Are tumours composed only of cancer cells?

Answer 26

A: No, they also contain fibroblasts, immune cells, and extracellular matrix.

Question 27

What is a key metabolic influence in the tumour microenvironment?

Answer 27

Nutrient availability and oxygen gradients.

Question 28

How does nutrient deprivation affect tumour metabolism?

Answer 28

It induces catabolic "starvation responses" to maintain survival.

Question 29

What happens to cells near blood vessels in a tumour?

Answer 29

They engage in anabolic metabolism to synthesise macromolecules.

Question 30

How does hypoxia affect tumour metabolism?

Answer 30

It triggers metabolic changes via hypoxia-responsive transcription factors.

Question 31

Name three transcription factors involved in hypoxia response.

Answer 31

HIF1, p53, and Myc.

Question 32

How do cancer-associated fibroblasts contribute to tumour metabolism?

Answer 32

They use lactate from cancer cells for energy, supporting tumour growth.

Question 33

How does metabolic reprogramming contribute to drug resistance?

Answer 33

It enables cancer cells to survive chemotherapy, radiotherapy, and targeted therapies.

Question 34

Why is targeting cancer metabolism a promising strategy?

Answer 34

It bypasses redundancy in genetic mutations and impacts all cancer hallmarks.

Question 35

Are anti-metabolic cancer therapies already in use?

Answer 35

Yes, some are already used for other diseases and could improve cancer treatment.

Question 36

What major metabolic pathways are altered in cancer cells?

Answer 36

Glycolysis, pentose phosphate pathway, serine synthesis, and glutamine metabolism.

Question 37

How can metabolism be studied at a snapshot level?

Answer 37

Using NMR Spectroscopy and Mass Spectrometry.

Question 38

How does metabolic tracing differ from metabolomics?

Answer 38

It tracks real-time metabolic flux using radiolabelled isotopes.

Question 39

What are the main cell-extrinsic factors influencing cancer metabolism?

Answer 39

Nutrient gradients, oxygen levels, and tumour microenvironment interactions.

Question 40

Why is cancer metabolism a crucial area of research?

Answer 40

It provides insights into tumour growth, drug resistance, and potential therapies.

Question 41

What experimental method allows live imaging of cancer metabolism?

Answer 41

FDG-PET imaging.

Question 42

What role does the tumour microenvironment play in metabolic adaptation?

Answer 42

It influences metabolic phenotypes through factors like oxygen and nutrient levels.

Question 43

What is the role of serine synthesis in cancer?

Answer 43

Supports nucleotide biosynthesis and antioxidant production.

Question 44

What metabolic pathway produces ribose-5-phosphate?

Answer 44

he Pentose Phosphate Pathway.

Question 45

How do cancer cells maintain ATP production when OxPhos is damaged?

Answer 45

They rely on increased glycolysis.

Question 46

What are two common metabolic alterations in colorectal cancer?

Answer 46

Increased glucose uptake and OXPHOS defects.

Question 47

Why is lactate production high in cancer cells?

Answer 47

Due to the Warburg Effect, where glycolysis is used even in oxygen-rich conditions.