Introduction Flashcards
Why have deaths due to disease decreased ?
better treatments, improved lifestyles, and identification of cause
What disease have we not decreased death in?
cancer
complex trait
- is caused by the interaction of multiple genes and environmental factors
- ex. cancer and heart disease
What causes the most deaths in Canada?
cancer
What diseases have we decreased the most deaths in?
heart diseases
highest incidence of cancer types in male
prostate, colorectal, lung
highest incidence of cancer types in female
breast, lung, colorectal
cancer with highest death rate in male
lung, colorectal, prostate
cancer with highest death rate in female
lung, breast, colorectal
why does lung have the highest death rate
- often not seen in scans until too late
- is a internal organ and easily accessible
- have similar symptoms to less serious issues
- lung cancers are often misdiagnosed
What cancers death rates have decreased?
breast, stomach, colorectal
What cancers death rates have increased?
lung
neoplasia
abnormal cell growth
benign growth
- slow growth
- tumour cells grow only locally and cannot spread by invasion or metastasis
- do not spread to other parts of body
malignant growth
- rapid growth
- invasive
- potential for metastasis
malignant cells
-malignant cells invade neighbouring tissues, enter blood vessels and metastasize to different sites
cancer
is a group of diseases involving abnormal cell growth with the potential to invade or spread to other parts of the body
3 parts of the cell cycle
birth, growth (differentiation), and death (apoptosis)
the cell cycle
- the timing mechanism that determines entry into cell division and ensures orderly passage through the events of cell division is critical
- is highly controlled and regulated by the body
defective cell cycle
- defective regulatory mechanism that limit cell division cause cells to undergo unregulated division
- causes cancer
tumour
uncontrolled cell division
cyclin accumulation
-regulator of the cell cycle
cyclin in the cell cycle
- when cyclin level are high, and it binds to Cyclin-Dependent Protein (Cdk) kinases, it is a signal for the cell cycle to go
- if the cell is able to go through the whole cell cycle, then the cyclin-cdk complex will be separated
What do normal cells need to grow?
- presence of essential nutrients
- growth factors
- density dependent inhibition
- anchorage dependence
cyclin
- controls the progression of a cell through the cell cycle
- is a growth factor
growth factors
proteins secreted by certain body cells that stimulate other cells to divide
density dependent inhibition
crowded cells stop dividing
anchorage dependence
cells must be in contact with solid surface to divide (e.g. extracellular tissue matrix)
malignant tumor
- divide without restraint
- invades tissues where it originated and spreads into other tissues
- eventually disrupts body function
2 genes that control the cell cycle
oncogenes and tumour suppressor
oncogenes normal function
cell growth and gene transcription
tumour suppressor normal function
DNA repair, cell cycle control
oncogenes and tumour suppressor in cancer
- activated oncogenes
- inactivated tumour suppressor
tumour suppressors
- “guardian(s) of the genome”
- often involved in maintaining genomic integrity
What do mutations in tumour suppressor genes lead to?
“the mutator phenotype”
-often the first 1st mutation in a developing cancer
p53
- “the guardian of the genome”
- sense genomic damage
- halts the cell cycle and initiates DNA repair
- if the DNA is irreparable, p53 will initiate the cell death process
six hallmarks of cancer
- self-sufficient growth signals (constitutively activated growth factor signalling)
- resistance to anti-growth signals (inactivated cell cycle checkpoint)
- immortality (inactivated cell death pathway)
- resistance to cell death (activated anti-cell death signalling)
- sustained angiogenesis
- invasion and metastasis
