HC1 - The nature of cancer

Question 1

tumors

Answer 1

• arise from normal tissue
• cannot maintain tissues of normal form and function

Question 2

histological features tumors

Answer 2

resemble tissue of origin

Question 3

begign

Answer 3

grow locally without invading adjecent tissue

Question 4

thyroid adenomas

Answer 4

• pre-malignant epithelial growth
• excessive release of thyroid hormone = hyperthryriodism

Question 5

pituitary adenoma

Answer 5

growth hormone > excessive growth = acromegaly

Question 6

malignant

Answer 6

invade nearby tissues and spawn metastases = 90% of deaths

Question 7

majority of tumors

Answer 7

epithelial cells

Question 8

epithelia

Answer 8

sheets of cells that line the walls of cavities and channels or cover the body

Question 9

lamina basalis

Answer 9

extracellular matrix, separates epithelial cells from stroma

Question 10

caricinomas (epithelia)

Answer 10

malignant

Question 11

squamous cell carcinomas

Answer 11

cells forming the protective layer

Question 12

adenomacarcinomas

Answer 12

specialized cells that secrete

Question 13

sarcomas (connective tissue)

Answer 13

-1% of cancers
- fibroblasts, collegen-secreting cells, adipocytes, osteoblasts, chondroblasts, myocytes

Question 14

hematopoietic tissue

Answer 14

precursors of erythrocytes, antibody-secreting plasma cells, T and B lymphocytes

Question 15

leukemia

Answer 15

spawned by malignant non-pigmented hematopoietic cells, freely moving through circulation

Question 16

lymphomas

Answer 16

malignant T or B lymphocytes that aggregate and form solid tumors, usually found in lymph nodes

Question 17

nervous system

Answer 17

gliomas, glioblastomas, neuroblastomas, schwannomas, medulloblastomas

Question 18

difficulty with classification

Answer 18

• transdifferentiation > from one lineage to another
• epithelial mesenchymal transformation (EMT)

Question 19

teratomas

Answer 19

• arise from germ cell precursors that persist at inappropriate sites in the developing fetus
• retain ability to generate most tissues
• genetic wildtype = no mutations

Question 20

dedifferentiation

Answer 20

shed virtually all tissue-specificity

Question 20

anaplastic tumors

Answer 20

no longer possible to identify the tissue from which they have arisen

Question 21

progressive cancer development

Answer 21

cancer cell populations evolve progressively to greater degrees of aggressive behavior = multi-step process

Question 22

cancer progression

Answer 22

normal-hyperplasmic- metaplasmic- dysplasia- neoplasmic - metastasis

Question 23

hyperplasmic growth

Answer 23

• excessive number of cells
• retain ability to assemble into a tissue that appear reasonably normal

Question 24

metaplasmic growth

Answer 24

normally present tissue is replaced with cells from a nearby tissue

Question 25

dysplasia

Answer 25

- transitional state between benign and malignant growth - variablity in nuclear shape and size,increased nuclear staining, increased size nucleus vs cytoplasma, increased mitotic activity, lack of normal cytoplasmic features - aberrant relative numbers of various cell types - major effects on tissue architecture

Question 26

adenomas, polyps, adenomatous polyps, papillomas, warts

Answer 26

- all contain cell types of normal epithelial tissue > greatly expended - respect boundry lamina basalis

Question 27

neoplasm

Answer 27

invasion into underlying tissues (stroma)

Question 28

monoclonal tumors

Answer 28

- descent from a single ancestor - myelomas = B cell precursors - particular chromosome rearrangement or mutation

Question 29

monoclonality

Answer 29

competition between multiple populations with different proliferation rates

Question 30

genetic heterogeneity

Answer 30

may mask monoclonal origin, genetic markers present in descendents

Question 31

normal cells in aerobic conditions

Answer 31

glycolysis and citric acid cycle > 36 ATP

Question 32

Warburg effect

Answer 32

many types of cancer cells use glycolysis even when exposed to oxygen

Question 33

anaerobic/hypoxic conditions

Answer 33

glycolysis> reduction of pyruvate to lactate > secretion lactate> 2 ATP

Question 34

hypoxia cancer

Answer 34

glycolysis for intermediates that can be used in biosynthesis

Question 35

overexpression of glucose transporters (GLUT1)

Answer 35

PET-scan > accumulation of radiolabeled glucose

Question 36

imported glucose

Answer 36

- normal cells = 30% - cancer = 1%

Question 37

cancer frequencies

Answer 37

- vary between populations - caused by random unavoidable accidents

Question 38

environment and genetics

Answer 38

determine cancer risk

Question 39

Barrett's esophagus

Answer 39

squamous cells are replaced by secretory cells of the stomach, esophageal adenocarcinomas