Test I: Stem, Cancer and Cancer Stem Cells

Question 1

Characteristics of Pluripotent Stem Cell

Answer 1

1. Large nucleus and small cytoplasm volume
2. Loosely packed chromatin, enriched histone markers
3. Underdeveloped, bioenergetically inactive mitochondria

Question 2

What is a stem cell?

Answer 2

A single cell that can replicate itself, or differentiate into many cell types.

Question 3

Properties of stem cells

Answer 3

1. Self-renewal : Maintaining the undifferentiated state
2. High Potency: Capable of differentiate to different cell types
3. Un-symmetric Division: give arise to daughter cells of different potency

Question 4

Tumor (neoplasm)

Answer 4

Occurs when an abnormal cell grows and divides out of control

Question 5

Cancer

Answer 5

If the neoplastic cells (tumor) can invade surrounding tissues

Question 6

Metastases/Secondary tumors

Answer 6

Forms when invasiveness allows the cancer cells to break loose, enter blood or lymphatic vessels

Question 7

Tumor progression

Answer 7

the concept that the development of a cancer requires a gradual accumulation of mutations in a number of different genes

Question 8

Evolution of cancer

Answer 8

an initial mild disorder of cell behavior evolving gradually into full blown cancer

Question 9

Angiogenesis

Answer 9

tumor induces the formation of new blood vessels

Question 10

Barriers to metastasis

Answer 10

-Difficult: Escape from parent tissue (invasiveness causes entry into vessel);
Colonization on remote site (Survival of cells in foreign tissue, initial growth, persistence of growth)
-Easy: travel through circulation (survival in the circulation, arrest in capillary or other small vessel, exit into remote tissue or organ)

Question 11

Properties that contribute to cancerous growth

Answer 11

• More self sufficient and relatively insensitive to anti-proliferative extracellular signals
• Less prone to undergo apoptosis
• defective in intracellular control mechanisms
• DNA damage; genetically unstable
• induce help from the normal stromal cells in their local environment
• induce angiogenesis
• invasive and metastasize
• produces telemorase, or acquire another way of stabilizing their telomeres

Question 12

Oncogene (overactivity mutation)

Answer 12

activates mutation, enables oncogene to promote cell transformation (dominant)

Question 13

Tumor suppressor gene (underactivity mutation)

Answer 13

two inactivating mutations functionally eliminate the tumor suppressor gene, promoting cell transformation (recessive)

Question 14

Cancer stem cells

Answer 14

Rare cells within tumors with the ability to selfrenew and give rise to the phenotypically diverse
tumor cell population to drive tumorigenesis

Question 15

How do cancer stem cells arise?

Answer 15

• Originates in a normal tissue stem cell

- Through a change in proliferating cell that is more differentiated, such as a transit amplifying cell

Question 16

totipotent

Answer 16

the ability of all living cells potentially to regenerate whole new individuals/fertilized egg that can differentiate

Question 17

pluripotent

Answer 17

potential of a cell to develop into more than one type of mature cell, depending on environment, and can differentiate into 3 germ layers

Question 18

multipotent

Answer 18

ability a cell to develop into closely related family of cells but cannot develop into any other kind of cell

Question 19

unipotent

Answer 19

progenitor cells, ex. hematopoeic cells

Question 20

List the tissue types that arise from the ectoderm.

Answer 20

Entire nervous system
Pituitary Gland
Adrenal Medulla
Cornea and lens
Epidermis and derivatives (hair, skin, nails, receptors)
Nasal, oral, and anal epithelia

Question 21

List the tissue types that arise from the mesoderm.

Answer 21

All muscle, bone, connective tissue
Entire CV systems, including BVs
Urogenital organs
Reproductive Ducts, gonads
Dermis of skin

Question 22

List the tissue types that arise from the endoderm.

Answer 22

GI tract epithelium (except mouth and anus)
GI glands (liver, pancreas, etc.)
Respiratory epithelium
Epithelial lining of urogenital organs
Urinary bladder