Cell Cycle Regulation in Cancer

The video explains cell cycle regulation at G1/S and G2/M checkpoints, focusing on the roles of retinoblastoma protein and p53. It highlights how these proteins control cell division and respond to DNA damage, preventing cancerous transformations. The video also previews the next topic on apoptosis.

What is the primary focus of cell cycle regulation in the context of cancer development?

• To understand mechanisms involved in cancer

• To increase genetic mutations

• To enhance cell division

• To promote apoptosis

Which protein is crucial for the G1/S checkpoint regulation?

• p53

• Retinoblastoma protein

• CDK1

• Cyclin B

What happens when the retinoblastoma protein is phosphorylated?

• It becomes active and arrests the cell cycle

• It releases E2F and allows transcription

• It binds to DNA and blocks transcription

• It degrades cyclin D

Which of the following is NOT a cause of G1/S checkpoint dysregulation in cancer cells?

• Loss of function of CDK inhibitor p16

• Overproduction of cyclin D

• Mutation in RB gene

• Increased activity of p53

What complex regulates the G2/M checkpoint?

• p53-MDM2

• Cyclin D-CDK4

• Cyclin B-CDK1

• Retinoblastoma protein

How does DNA damage affect the G2/M checkpoint?

• It activates cyclin B-CDK1 complex

• It leads to inactivation of phosphatase

• It promotes cell cycle progression

• It enhances cyclin D synthesis

What role does p53 play in response to DNA damage?

• It promotes cell division

• It repairs DNA damage and induces apoptosis

• It degrades cyclin B

• It activates CDK1

What happens to p53 in normal cells under non-stress conditions?

• It induces apoptosis

• It repairs DNA

• It is phosphorylated and active

• It is bound to MDM2 and degraded

Which process is NOT directly regulated by p53?

• Protein synthesis

• Cell cycle arrest

• DNA damage repair

• Apoptosis

What is the consequence of p53 inactivation due to mutations?

• Stable genome

• Uncontrolled cell cycle progression

• Enhanced DNA repair

• Increased apoptosis