Cancer (1) A- Hallmarks of Cancer
Hallmarks of Cancer
1. Be able to explain that cancers are complex tissues 2.To be able to describe the essential alterations in cell physiology that collectively dictate malignant growth. 3. Be able to discuss how cancer development is a multi-step process.
What do these stand for in relation to cancer? CAF EC PC CSC CC IC ICC
CAF: Cancer- Associated Fibroblast EC: Endothelial Cell PC: Pericyte CSC: Cancer Stem Cell CC: Cancer Cell IC: Immune Inflammatory Cell ICC: Invasive Cancer Cell
Compare and contrast the characteristics of Cancer cells and Normal cells
Cancer cells - Loss of contact inhibition - Increase in GF secretion - Increase in oncogene expression - Loss of TSG's - Neovascularisation Normal cells - Oncogene expression is rare - Intermittent or coordinated SF secretion - Presence of TSGs
The ability of tumor cell pop's to expand in number is determined not only by the rate of proliferation but also by the rate of....
Cell attrition The process of reducing something's strength or effectiveness - Apoptosis is a major part of cell attrition
Explain how normal cells work w/ regards to GS's and how this is different in cancer cells
Normal cells: require GS's before they can move from a quiescent state into an active proliferative state Many oncogenes in the cancer act by mimicking normal growth signalling and tumor cells can generate their own growth signals, which leads to their dependence on stim. from their normal tissue environment
Explain how normal cells work w/ regards to Anti-GS's and how this is different in cancer cells
Normal tissue: multiple antiproliferative signals operate to maintain cellular quiescence & tissue homeostasis; These growth-inhibitory signals. like their GS counterparts are received by transmembrane cell surface receptors coupled to intracellular signalling circuits.
Anti-GSs can block proliferation by 2 distinct mechanisms which are...
(1) Cells forced out of activeproliferative cycle into the quiescent (G0) (2) May be induced to permanently give up their proliferative potential by being induced to enter postmitotic state associated w/ differentiation
The main 6 Hallmarks of Cancer (TARAGG)
1. TISSUE invasion & metastasis 2. Sustained ANGIOGENESIS 3. Limitless REPRODUCTIVE Potential 4. Evading APOPTOSIS 5. Self-sufficiency in GROWTH SIGNALS 6. Insensitivity to Anti-GROWTH SIGNALS
Define an Oncogene
A cancer inducing gene A gene that can transform cells
Define a Tumor Supressor
A gene whose partial or complete inactivation, occurring in either the germ line or the genome of a somatic cells, leads to an increased likelihood of cancer developing Such a gene is responsible for constraining cell proliferation
List the 4 EMERGING HALLMARKS of cancer (There are 2 Emerging & 2 Enabling)
EMERGING - Deregulating cellular energetics - Avoiding immune destruction ENABLING - Genome instability & Mutation - Tumor-promoting inflammation
The mechanisms listed below will lead to which of the 6 hallmarks of cancer (TARAGG) Loss of p53 Activate H-RAS oncogene Lose retinoblastom
Evading APOPTOSIS - Loss of p53 Self-sufficiency in GROWTH SIGNALS - Activate H-RAS oncogene Insensitivity to Anti-GROWTH SIGNALS - Lose retinoblastom
Define 'contact inhibition'
It is a regulatory mechanism that functions to keep cells growing into a layer one cell thick. This process continues until the cells occupy the entire substratum, at this point normal cells will stop replicating.
The mechanism listed below will lead to which of the 6 hallmarks of cancer (TARAGG) Turn on telomerase
Limitless REPRODUCTIVE Potential - Turn on telomerase
The mechanism listed below will lead to which of the 6 hallmarks of cancer (TARAGG) Produce VEGF inducer
Sustained ANGIOGENESIS - Produce VEGF inducer
The mechanism listed below will lead to which of the 6 hallmarks of cancer (TARAGG) Inactivate E-cadherin
TISSUE invasion & metastasis - Inactivate E-cadherin
Oncogene. Tumor suppressor. Which constrains cell proliferation?
TS