Cancer and Stem Cells

​Lesson 3: Cell Cycle Control and Cancer
Essential Question: How does cell specialization
change over the life cycle of organisms?
Summary:
Students will relate the regulation of the cell cycle and apoptosis to the health of organisms. Students will explain
the role of signals in cell differentiation and consider ethical and research questions related to stem cells. Hands-on investigations will support learning about features, causes, prevention, and treatment of cancer.

TEKS 6.B Explain the process of cell specialization through cell differentiation, including the role of environmental factors.

TEKS 6.C Relate disruptions of the cell cycle to how they lead to the development of diseases such as cancer.

​Lesson 3 Vocabulary
•cyclin

•cyclin-dependent kinase (CDK)

•apoptosis

•stem cell

•growth factor

•cancer

•carcinogen

Cyclins- proteins that bind to enzymes in the cell cycle

The role of cyclins

•In the G1 stage of interphase, a combination of cyclin with CDK signals the start of the cell cycle.

•Different cyclin/CDK combinations signal other activities, including DNA replication, protein synthesis, and mitosis.

•Then, the breakdown of one type of cyclin causes a drop in CDK activity, which triggers telophase and cytokinesis.

Quality control checkpoints

•The cell cycle has built-in checkpoints that monitor the cycle and can stop it if something goes wrong.

•A checkpoint near the end of the G1 stage monitors for DNA damage and can stop the cycle before it enters the S stage of interphase.

•Spindle checkpoints also have been identified in mitosis, so if a failure of the spindle fibers is detected, the cycle can be stopped before cytokinesis.

Quality control checkpoints

Cell Regulation

•Some cells go through a process called APOPTOSIS, or controlled cell death.

•Apoptosis is different from uncontrolled death of injured cells.

Multiple Choice

Apoptosis is.....

• Controlled cell death

• Uncontrolled cell death

• Unregulated cell division

• Cell growth

Stem Cells
Stem cell- a cell that can be directed to give rise to specialized cells.
•Growth factors-help regulate mitosis and cell differentiation.
Differentiation- what gives us different cells like skin, muscle, stomach.
Two types of stem cells; embryonic (during pregnancy) and adult stem cells (after birth)

Multiple Choice

Stem cells that develop during pregnancy are....

• Embryonic

• Adult

Multiple Select

Which of the following help regulate cell division? Select all that apply.

• Apoptosis

• Growth factors

• Stem Cells

Cancer
•Cancer is the uncontrolled growth and division of cells.
•If apoptosis does not occur when it should (due to a mutation), a tumor of cancerous cells can result.
•Carcinogens- Substances and agents that are known to cause cancer.
Yes, environmental factors can cause cancer!
Examples:
UV light-skin cancer
Tobacco use-lung/gum cancer

Multiple Select

Which of the following can cause cancer?

• Problems with checkpoints in the cell cycle

• Carcinogens

• UV/Sunlight

Cancer Treatment
•Chemotherapy, radiation, immunotherapy and stem cell therapy are all ways in which cancer can be treated.

•Not all cancers have a cure.