Hallmarks of Cancer -- Quiz 1

Question 1

Hallmarks of Cancer

Answer 1

Originally Comprised of six biological capabilities acquired during the multistep development of human tumors.

Question 2

What are the six original Hallmarks of Cancer?

Answer 2

• Sustaining proliferative signaling
• Evading growth suppressors
• Activating invasion and metastasis
• Enabling replicative immortality
• Inducing angiogenesis
  and
• Resisting cell death

Question 3

What does normal cell growth depend on?

Answer 3

• The timing and the rate of cell division and a controlled Cell cycle
• multiple systems are put into place to ensure that cells proliferate only when the body needs them and that damaged cells (genomes are eliminated)

Question 4

What are two types of genes that are mutated in tumor cells?

Answer 4

• Oncogenes (the “normal” version proto-oncogene)
• Tumor suppressors

Question 5

Proto-oncogenes

Answer 5

Activity: Simulate cell cycle progression
Mutation in cancer: gain of function
Specific Hallmark: sustaining proliferative signaling
GASS PEDAL

Question 6

Tumor suppressors

Answer 6

Activity: Inhibit cell cycle progression
Mutation in cancer: Loss of Function
Specific Hallmark: Evading growth suppressors
BREAK PEDAL

Question 7

When does programmed cell death (Apoptosis) occur?

Answer 7

It occurs in response to cellular stresses such as DNA damage when the damage cannot be repaired. An apo

Question 8

Hallmark: Resisting cell death

Answer 8

Apoptosis

Question 9

Hallmark: Enabling replicative immortality

Answer 9

• Normal human cells have a finite ability to proliferate due, in part, due to the ends of chromosomes (telomeres) shortening after each replication
• Once a normal cell reaches this limit, it enters cellular senescence (or apoptosis)
• Cancer cells must subvert this cell division counting mechanism and become immortal

Question 10

Hallmark: Enabling replicative immortality - Telomere length functions

Answer 10

Telomere length functions as a molecular clock that computes the number of cell divisions. When telomeres become critically short, cell division ceases. the cells are “mortal”

Question 11

What are hallmark characteristics gained by?

Answer 11

They are gained by a stepwise accumulation of mutation. Most estimates are for a minimum of 6-7 mutations.

Question 12

Tumor Microenvironment

Answer 12

• Certain hallmarks of cancer are accomplished by the establishment of a tumor microenvironment
• Cancer cells can change the microenvironment

Question 13

How is Cancer a Microevolutionary Process?

Answer 13

• Multicellularity requires cellular cooperation
• • The genome has rules for how to prevent cells from cheating
• Cancer is a cheating phenotype

Question 14

What are the five foundations of Multicellularity? What hallmarks are they connected to?

Answer 14

• Proliferation inhibition –> uncontrolled proliferation
• controlled cell death –> inappropriate cell survival
• extracellular environment –> environmental degradation
• division of labor –> dysregulated differentiation
• resource allocation –> resource monopolization

Question 15

Subclonal mutations

Answer 15

a clone that is descended from another clone but has acquired additional mutation(s).

Question 16

Stem Cells

Answer 16

• the ability to self-renew
• the ability to differentiate into specialized cells

Question 17

Dedifferentiation

Answer 17

• Reversion of a more differentiated cell to the phenotype of a less differentiated cell, such as its stem cell precursor

Question 18

Differentiation

Answer 18

• Process whereby a cell acquires a specialized phenotype, such as a phenotype of a less differentiates cell, such as a stem cell precursor