ecology of cancer Flashcards
what is an invasive species and what can lead to invasion
- an organism that is nit native to an environment
can occur in: - species poor habitats
- distrubed habitats
- isands (evolutionary isolation0
What is the stage- based approach to identifying an ‘invasive species.?’
Stage based approach: can you propagate an environment and survive there. Invasion stages: Transport, establishment, spread, and impact
Transport: can you get there. Leads to either death or capaivity or introduction to enviorment
Establishment: establish in the environment. Leads to fail or establish
Spread: does it have ability to outcompete other species. Leads to remains local or spreads
Impact: human perceived impact. Range of low to high, based on how humans view it
Why is a stage-based approach effective for identifying potential invasive species? How does this relate to our definition of ‘sustainability?’
Reasons to use stage based approach:
1. Some pops succeed and become invasive but others so not; focus on population phenomena
2. Life history or environmental characters may influence whetehr a species is ‘invasive’ or not; focus on stage specfic factors is easier and more informative
3. We can assess (human) interaction (pos or neg) at each stage of process
- allows us to assess potential invasive species at different stages and respond appropriately
- can do a similar thing while analyzing sustainability. Assess on stage based approach
- different stages allows us to assess the environment and assess sustainability of environemnt. We want to protect environments. By assessing invasive species, we can mitigate the affects invasive species have which helps protect biodiversity and ecosystem servies. This protects the integrity of an ecosystem. Rehabilitate not restore
What is an evolutionary ‘Stable State’ vs an evolutionary ‘Stable Strategy?’
Stable state strategy: a life strategy whereby, if every member of a population adopts it, no mutant strategy can invasive. Ex. if all doves in environment, happy. If a hawk comes in, east the dove an disrupts the environment
Stable state: an evolutionary state where the genetic composition of a population is maintained, even after disturbance, pending too large a disturbance. Ecosystem integrity. What is buffering capacity before yu get distubrance
Draw, and annotate, a diagram that communicates a system changing to an alternative stable state.
ess and again diagram??????
What is the ‘niche space’ associated with the human ecosystem? How does this relate to cancer as an invasive species?**
- human body requires things to survive/live. Ex. oxygen avalibilty, water, extracellular resorces, pH, etc
- if cancer disrupts these, it impats abiloty to survive
- cancer cells invade, can they estabilish?
Identify and explain the key physiological steps in cancerous cells acting in the mammalian/human body. How is this analogous to an invasive species (the establishment and invasive phases).
glycoltic metabolism
- a mutated cell survuves and starts profliferatinf in the tissue
- oxygen avilibility decreses w/in tumor (dec SA:V ratio)
- interior cells switch o glycoltic metabolism
- glyolysisand lactic acid fermentation create acidic microenvironemtn arounf tumor. this creates a short term pos feedback loop. alleopatic comp.
- normal somation cells are exculded from acidic environment
hypoxia: positive feedback and angiogenesis
- HIF1 mediates the effects of hypoxia promoting aniogenesis
- in normoxic conditions: HIF1 alpha unit is degraded in the presence of o2
- prodycts of glyoysis: lacate and pyruvate- maintain acidos and allow upreg of HIF1 and hypoxia
- as HIF1 producion increases, presence of HIF1 alpha stimulates vascular endotheial growth factor promoting angiogenesis to the tumor
immune response mediation
- increases HIF1 production down reuglates CD8+ T-cell (cells that protect against invaders) activation, supressing the immune response
- deactivation of tcells lead sto recruitment of tumore associatated macrophages (TAMs) providing more growth factors for tumor cells
- cells are distracted so tumore can grow
- also, promotion of VEGF further supresses tcells
What is hysteresis?
conservation/treatmet is a hysteric phenomenon
- the path back is not the same as the path there
Are there any psychological components to the ecology of cancer?
- stress can lead to increased risk for cancer
- psychological factors
- placebo effect
ess and aging
hypothesis: aging is the enviormental disurbance that faciltaes cancer invasin
- stable state
- then cells are pushed to a point where they age enough and could form cancer
- alternate state. not nescessarilty stable. the state of cancer
cancer suscetibility and trade offs
- eco-immunological: infections, sleep, growth
- reproduction: secondard sexual traits, sexual hormones
- supression: cell-intrinisic chelc, organs-specifc trade-offs, tissue repair, auto immunity
- prevention: behavioural adjustemnet
- alleviateion: life-histrory trait adjustments/cancer fitness costs
- at the right time, could get to a point where cancer will happen based on these factors
hallmarks of cancer
- self sufficiney in growth signals
- insensitivy to antigrowth signals
- evasion of apoptosis
- limitless replicative potential
- sustained angiogenesis
- tumor invasion and metastasis
ecology of the establishment phase
- pos feedbakc of hypoxia and acidosis analogous to alleopathic comp
-t cell mitigratiois analogous to predator avoidance
problem of invasive species/cancer ecology
- proactive approach- prevention
- detection of potenial invaders before establishment
- prevent cancer from forming - reactive approach (conservation/treatment)
- determine how established invaders impact ecological systems
- determine cancer effects and try and treat them - reactive approach (conservation/treatment)
- hystereretic phenomenon
- path back is not the same as the path there
