###
What are immune checkpoints? Immune checkpoints are a normal part
of the immune system. Their role is to prevent an immune response from
being so strong that it destroys healthy cells in the body.
###
How do immune checkpoint inhibitors work? By blocking checkpoint
proteins from binding with their partner proteins. This prevents the "off"
signal from being sent, allowing the T-cells to kill cancer cells.
###
Explain hallmark "Sustaining proliferative signalling" of cancer. This
hallmark describes the ability of cancer cells to continuously signal
themselves or nearby cells to proliferate, leading to uncontrolled growth
and tumor formation.
- Abnormal receptors (always activated).
- Produce their own activation signals.
- Activation of downstream signalling pathways.
###
Explain hallmark "Resisting cell death" of cancer. The ability of cancer
cells to evade the normal mechanisms of apoptosis that eliminates
damaged or unneeded cells. This resistance allows cancer cells to survive
longer than they should
- Tumor cells escape programmed cell death.
- Tumor cells are set to survive even when damaged.
- Cell death programs are altered.
###
Explain hallmark "Evading growth suppressors" of cancer. Ability of cancer
cells to bypass the regulatory mechanisms that normally inhibit cell
proliferation. This evasion allows cancer cells to grow uncontrollably,
contributing to tumor development and progression.
- Tumor suppressors block cell proliferation when cells are damaged (p53,
Rb).
- Tumor suppressors are often mutated in cancers.
###
What is p53? A tumor suppressor gene.
,###
In a healthy cell p53 is always present in a high/low concentration. Low.
###
The activity of p53 is regulated primarily at the level of:
a. transcription.
b. translation.
c. degradation. c. degradation.
###
Explain how cancer cells evade anti-growth signals. Tumor suppressors
(such as p53 and Rb) normally halt cell proliferation when DNA is
damaged. In cancer, these genes are often mutated or inactivated,
allowing uncontrolled cell growth.
###
Explain hallmark "Enabling replicative immortality" of cancer. Ability of
cancer cells to bypass the normal limits on cell division, allowing them to
proliferate indefinitely.
- Altered telomeres; cancer cells can restore telomeres (that's why they
have high proliferation rate).
- Continued replication.
- Immortal cells in culture.
###
Explain hallmark "Inducing angiogenesis" of cancer. The process by which
tumors stimulate the formation of new blood vessels from existing ones.
This is crucial for tumor growth and metastasis, as it provides the
necessary nutrients and oxygen to support the rapidly proliferating cancer
cells.
- Lack of nutrients drives angiogenesis.
- Activating blood vessel formation (VEGF).
- Immune cell infiltration promote angiogenesis.
###
What is angiogenesis? Formation of new blood vessels.
###
,What does Vascular Endothelial Growth Factor (VEGF) do? A chemical our
cells make that causes blood vessels to grow toward the cell to feed it.
This chemical is made in excess by cancer cells which need excess
nutrients.
###
What role does angiogenesis play in cancer, and which factor is central to
this process? Angiogenesis provides tumors with nutrients and oxygen
by forming new blood vessels. It is driven by VEGF (vascular endothelial
growth factor) and is promoted by immune cell infiltration.
###
Explain hallmark "Activating invasion and metastasis" of cancer?
Ability of cancer cells to spread from their original site (primary
tumor) to distant organs and tissues, forming secondary tumors.
- Cell undergo epithelial to mesenchymal transition.
- Spread of cancer to distant sites.
###
Which hallmark of cancer is the most likely cause of death for a cancer
patient? Activating invasion and metastasis.
###
In very simple terms, what does glycolysis do? Converts glucose into
pyruvate, producing energy in the form of ATP and NADH in the process.
###
Where in the cell does glycolysis occur? In the cytoplasm of the cell,
where glucose is converted into pyruvate.
###
What is the main advantage of glycolysis? It produces energy very
fast, without requiring oxygen.
###
Why is ATP required for glycolysis? ATP is required to split the glucose
molecule into two pyruvate molecules.
###
, What is the total ATP yield of glycolysis? Per glucose molecule: 4 ATP
molecules are produced in the process, 2 are consumed in the process
itself. So, the net number of ATPs produced in glycolysis is 2.
###
The process where glucose is converted to pyruvate is called: glycolysis.
###
Pyruvate can do two things: 1. Conversion to Acetyl-CoA: Pyruvate can be
transported into the mitochondria, where it is converted into acetyl-CoA by
the enzyme pyruvate dehydrogenase.
2. Lactic Acid Fermentation: In anaerobic conditions (absence of oxygen),
pyruvate can be converted into lactic acid through lactic acid
fermentation. This process occurs in muscle cells during intense exercise
when oxygen levels are low.
###
Fatty acid oxidation (FAO) pathway happens in: the mitochondria.
###
Glutamine is important for cancer cells. However, for it to be transported
into the TCA cycle, it first needs to be converted to: glutamate.
###
Which amino acid is mainly essential for cancer cell growth?
Glutamine.
###
What are the two main functions of the pentose phosphate pathway (PPP)?
1. Generating NADPH.
2. Producing ribose-5-phosphate.
###
The pentose phosphate pathway (PPP) generates ribose-5-phosphate.
What is ribose-5-phosphate used for? It is a precursor for the synthesis
of nucleotides.
###
NAPDH and ribose-5-phosphate is produced by which pathway? The
pentose phosphate pathway (PPP).