3.1 Detecting cancer

Question 1

5 risk factors for Cancer

Answer 1

Smoking
Radiation/UV ray exposure
Viral Infections
Genetic Mutations
Unhealthy Lifestyle

Question 2

Cancers associated w/risk factor

Answer 2

1. Smoking - Lung, oral, colon, bladder, & breast cancers
2. Radiation/UV ray exposure - Skin cancer
3. Viral Infections - HPV=cervical cancer, Epstein-Barr virus= lymphoma, Hep B= liver cancer
4. Genetic Mutations (inherited) - BRCA1 & BRCA2 mutations  breast & ovarian cancer
5. Unhealthy Lifestyle (overweight, no exercise) - Colon & prostate cancer

Question 3

most ______ perform ______ _____ to help identify & start to treat medical conditions

Answer 3

radiologists
diagnostic imaging

Question 4

imaging can clue in on cancers like_______  _____ _____can identify tumor in bone, MRI can identify strange masses in bone (especially when cancer has metastasized), bone scan shows entire skeleton & where cancer has spread (tracks active bone changes “hot spots”)

Answer 4

osteosarcoma
x-ray

Question 5

Images of bones, teeth, lungs,
breasts, heart, blood vessels,
digestive tract

Answer 5

X-ray

Question 6

• Computerized (Axial) Tomography
• VERY DETAILED images -> especially of
  bones, chest, abdomen, pelvis, spine,
  brain

Answer 6

CT scan

Question 7

 Magnetic Resonance Imaging
 Brain, spine, joints, abdomen,
blood vessels, pelvis

Answer 7

MRI

Question 8

• Type of nuclear imaging test
   Helps diagnose & track several
  bones diseases & cancers like
  osteosarcoma

Answer 8

Bone scan

Question 9

VERY DETAILED images

Answer 9

CT scan

Question 10

 NO RADIATION= SUPER SAFE

Answer 10

MRI

Question 11

 EXTREMELY SENSITIVE

Answer 11

Bone scan

Question 12

 Quick & painless, but exposed to
radiation
 MAY have to inject a contrast dye
to help w/ imaging
 Hard to be done on ppl w/
implanted devices

Answer 12

X-ray

Question 13

 Painless & non-invasive
 More detail than X-ray  more accurate
diagnoses of cancers like lung, bowel,
liver, & kidney cancers
 Can be done on ppl w/ implanted metal
devices
 Exposed to radiation

Answer 13

CT scan

Question 14

 NO RADIATION= SUPER SAFE
 Great detail of soft tissue 
identification & diagnoses of
diseases

Answer 14

MRI

Question 15

 EXTREMELY SENSITIVE to
variations in bone metabolism &
abnorms.
 Small amt. radiation

Answer 15

Bone scan

Question 16

Procedure:
 Machine send photons (X-ray
particles) into body to come in
contact w/ tissues & produce
image on metal film
 Shows 2D image
 Dense structures like bone appear
white b/c absorb radiation
 Structures including air appear
black
 Muscle, fat, fluid appear gray

Answer 16

X-ray

Question 17

Procedure:
 Performed in large X-ray tube  patient
lays down & is inserted into tube
 Tube rotates around patients to get
multiple images of different slivers of
body
 Multiple X-ray images from different
angle produced  cross-sectional
images of bones & soft tissue

Answer 17

CT scan

Question 18

Procedure:
 Performed inside large,
magnetic tube
 Person lies down while
machine scans body by turning
small magnets on & off within
tube
 Magnets send radio waves thru
body  waves bounce back &
are interpreted by MRI
machine to produce image
 Produces cross-sectional
images, especially for SOFT
TISSUES

Answer 18

MRI

Question 19

Procedure:
 Injected w/ tracers (tiny
radioactive particles called
radionuclides) that will circulate
thru body & get absorbed into
bones
 Patient lies on table while
machine passes a gamma
camera over them to record
patterns of tracer absorption
 2D images that examine
skeleton for abnorms.

Answer 19

Bone scan

Question 20

a malignant tumor of cells growing uncontrollably

Answer 20

cancer

Question 21

50 divisions, but cancer cells grow indefinitely

Answer 21

Cell cycle limit

Question 22

______ _____ gets damaged when dividing & breaks free from normal cell division limits

Answer 22

ONE CELL

Question 23

_____ ___ ____ in nucleus often  cancer

Answer 23

changes in DNA

Question 24

cells typically die after 50 divisions. Why?

Answer 24

 prevents them from becoming too damaged

Question 25

____ occur spontaneously or b/c of radiation & chemicals

Answer 25

mutations

Question 25

____ occur spontaneously or b/c of radiation & chemicals

Answer 25

mutations

Question 26

CANCEROUS cells ____ ____ (tumors) & in ___ ___ ___ ___

Answer 26

different shapes & sizes

Question 27

ALL CANCEROUS CELLS ARE UNIQUE FROM EACHOTHER  treatments only kill SOME of the cancer cells, while others are resistant

Answer 27

-

Question 28

 To identify cancer, will first do screenings then a ____ will confirm malignant cells

Answer 28

biopsy

Question 29

_____  “cell suicide” that SHOULD occur when DNA is damaged; cancer cells won’t undergo apoptosis

Answer 29

Apoptosis

Question 30

______  vessels created that connect to tumors – FEED tumors & let them spread

Answer 30

Angiogenesis

Question 31

-______ “everywhere staying” – when tumor spreads from original tumor post angiogenesis

Answer 31

Metastasis

Question 32

_____- a transcription factor that codes for the transcription of a gene that will release protein to end cell cycle – triggers the release of a protein that induces apoptosis

Answer 32

p53

Question 33

 “accelerator/GAS PEDAL”  Responsible for telling cells when to divide -> only when need new cells

Answer 33

HEALTHY = PROTO-ONCOGENE

Question 34

 Are induced/turned up in cancer cells  Like the “gas pedal being stuck down”  will allow cells to divide without necessary signals  When cells allowed to grow infinitely, more likely to mutate  CAUSE cancer

Answer 34

CANCEROUS = ONCOGENE

Question 35

 “brakes” of cell division  Responsible for telling cells to stop dividing once enough cells have been created  Have two copies of genes  even if one damaged, can still stop division – p53 gene

Answer 35

HEALTHY= TUMOR SUPPRESSOR GENE

Question 36

 Suppressed/turned down in cancer  No longer stop cell division  cancerous cells continue to grow w/ mutated DNA

Answer 36

CANCEROUS = MUTATED TUMOR SUPPRESSOR GENE

Question 37

 “editors of the newspaper” –ACTIVE WITHIN THE CELL CYCLE  code for proteins that fix errors in DNA  TYPE of tumor suppressor gene  Needed to prevent cancer CANCEROUS = MUTATED DNA RE

Answer 37

HEALTHY= DNA REPAIR GENE

Question 38

 Suppressed/turned down by cancer  “drunk editors” not doing their job to fix the DNA  BRCA1 & BRCA2

Answer 38

CANCEROUS = MUTATED DNA REPAIR GENE

Question 39

 ___ ____ = gene “chip” that allows us to look @ thousands of genes at once  study GENE EXPRESSION

Answer 39

DNA microarray

Question 40

PROCESS: 1. Collect Tissue Samples 2. Isolate RNA - (dissolve sample into solution so RNA stays in supernatant & all else trashed) 3. Isolate mRNA – only mRNA contain “Poly-A” tails, so wash the RNA over columns w/ small beads that will bind w/ tails then rinse into other tube 4. Make Labeled DNA Copy – add green labeling mix to healthy sample & red to cancerous (labeling mix= make complementary DNA strands to the RNA (cDNA) that correspond to genes) 5. Apply DNA- (little piles of single-stranded DNA already on microarray; each spot has identical copies of one gene that’s tracked in computer database); add cDNA from mix & the stands will bind onto spots 6. Scan Microarray – scan green & red separately, then combine image 7. Analyze Data

Answer 40

DNA microarray

Question 41

___= expressed in healthy cells, but TURNED DOWN in cancer (b/c no red cDNA attached)  mutated like mutated tumor suppressor genes

Answer 41

Green

Question 42

____= not expressed in healthy cells, but TURNED UP in cancer (b/c no green cDNA attached)  mutated like oncogene

Answer 42

Red

Question 43

____= expressed EQUALLY in healthy & cancerous cells, expression not affected by cancer  no mutation

Answer 43

Yellow

Question 44

____= gene expressed in NEITHER healthy or cancerous cells

Answer 44

BLACK

Question 45

 Convert colors to numbers based on intensity of red & green  the____ the color, the_____ the number

Answer 45

BRIGHTER HIGHER

Question 46

 Ratio GREATER than 1 =

Answer 46

gene induced by tumor formation (red>green)

Question 47

 Ratio LESS than 1 =

Answer 47

gene suppressed by tumor formation (green> red)

Question 48

 Ratio EQUAL TO 1 =

Answer 48

gene not affected by tumor growth (green copies=red copies)

Question 49

 Ratio of ZERO =

Answer 49

gene not expressed in either cell (black)

Question 50

positive =

Answer 50

gene expressions behave similarly

Question 51

positive =

Answer 51

gene expressions behave similarly

Question 52

negative =

Answer 52

gene expressions behave oppositely

Question 53

one=

Answer 53

gene expressions identical

Question 54

zero =

Answer 54

gene expressions behave in unrelated manner