Podcast Beta
Questions and Answers
What is a characteristic of cancer cells that allows them to grow and divide without external growth signals?
What is an example of autocrine signaling in cancer cells?
What is the consequence of constitutive activation of growth factor receptors in cancer cells?
What is the result of cancer cells bypassing normal cell cycle checkpoints?
Signup and view all the answers
Which of the following is an example of a growth factor produced by cancer cells?
Signup and view all the answers
What is a consequence of cancer cells becoming resistant to anti-growth signals?
Signup and view all the answers
What is the primary characteristic of self-sufficiency in growth signals in cancer biology?
Signup and view all the answers
Study Notes
Self-sufficiency in Growth Signals
Definition
- Normal cells require growth signals to proliferate and survive
- Cancer cells acquire the ability to grow and divide without these external signals, becoming self-sufficient
Key Features
- Autocrine signaling: Cancer cells produce their own growth factors, stimulating their own growth and proliferation
- Constitutive activation: Cancer cells have constitutively active growth factor receptors, allowing them to respond to growth signals even when they are not present
- Bypass of normal checkpoints: Cancer cells can bypass normal cell cycle checkpoints, allowing them to continue growing and dividing despite DNA damage or other abnormalities
Examples
- Autocrine growth factor production: Cancer cells producing platelet-derived growth factor (PDGF), epidermal growth factor (EGF), or transforming growth factor-alpha (TGF-α) to stimulate their own growth
- Mutations in growth factor receptors: Activating mutations in receptors such as HER2 or EGFR, leading to constitutive activation and uncontrolled growth
Consequences
- Uncontrolled growth and proliferation: Cancer cells can grow and divide rapidly, leading to tumor formation and progression
- Resistance to anti-growth signals: Cancer cells can become resistant to anti-growth signals, such as TGF-β, which normally inhibit cell growth and division
Self-sufficiency in Growth Signals
Definition
- Normal cells rely on external growth signals to proliferate and survive
- Cancer cells acquire ability to grow and divide without external signals, becoming self-sufficient
Key Features
- Cancer cells produce their own growth factors, stimulating their own growth and proliferation through autocrine signaling
- Constitutively active growth factor receptors in cancer cells allow them to respond to growth signals even when not present
- Cancer cells can bypass normal cell cycle checkpoints, continuing to grow and divide despite DNA damage or other abnormalities
Mechanisms
Autocrine Signaling
- Cancer cells produce platelet-derived growth factor (PDGF), epidermal growth factor (EGF), or transforming growth factor-alpha (TGF-α) to stimulate their own growth
- Examples of autocrine growth factor production include PDGF, EGF, and TGF-α
Constitutive Activation
- Activating mutations in receptors such as HER2 or EGFR lead to constitutive activation and uncontrolled growth
- Mutations in growth factor receptors result in continuous signaling, driving cancer cell growth and proliferation
Consequences
- Uncontrolled growth and proliferation of cancer cells lead to tumor formation and progression
- Cancer cells become resistant to anti-growth signals, such as TGF-β, which normally inhibit cell growth and division
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Learn about the characteristics of cancer cells, including autocrine signaling and constitutive activation, which enable them to grow and divide without external growth signals.