Name: tumor suppressor gene loss in cancer
Uploaded: 2023-04-30T18:28:51.000Z
Duration: 1 min 12 s
Channel: JoVE

K12 Standards

Florida Department of Education

High School

Life Science

SC.912.L.16

SC.912.L.16.8

Loss of Tumor Suppressor Gene Functions

In a healthy cell, tumor suppressor genes act as the gatekeepers that control cell growth and proliferation and promote cell apoptosis.
Hence, when a tumor suppressor gene is inactivated, cells may start growing out of control leading to cancer.
Fortunately, in most cases, the inactivation of a single allele of a tumor suppressor gene does not lead to tumor progression. Both of the alleles must lose their function for the cells to become cancerous.
Such loss of function mutations in tumor suppressor genes can be caused by genetic alterations such as point mutations,&#160; chromosomal deletion,&#160; or errors in chromosome segregation.
However, a few epigenetic changes can also permanently inactivate the tumor suppressor genes. For example, if a gene undergoes modifications in its promoter region or gets packaged into the heterochromatin region of a chromosome, it can make irreversible and heritable changes to the gene expression pattern.

loss of tumor suppressor gene functions

Tumor suppressor genes are normal genes that can slow down cell division, repair DNA mistakes, or program the cells for apoptosis in case of irreparable damage. Hence, they play an essential role in preventing the proliferation of damaged cells.
When the tumor suppressor genes develop mutations or are lost, cells start growing out of control, leading to cancer. However, a single functional copy of the tumor suppressor gene is enough for the cells to maintain their normal functions and cell cycle. It&#39;s only when both the copies of the gene are inactivated or lost that the cells lose control and become cancerous.
Some common tumor suppressor genes that have implications in human cancer include TP53, Rb, INK4, PTEN, APC, BRCA1/BRCA2, and MADR2. Loss of function mutations in these tumor suppressor genes has implications in many types of cancers, including ovarian, lung, colorectal, head and neck, pancreatic, uterine, breast, and bladder cancer.

Tumor suppressor genes are normal genes that can slow down cell division, repair DNA mistakes, or program the cells for apoptosis in case of irreparable ...

Education

JoVE Core

Cell Biology

Unit 1

Cancer

KEY TERMS AND CONCEPTS

tumor suppressor gene loss in cancer

Tumor suppressor gene loss can help cancer cells grow and survive. Tumor suppressor genes normally help control cell growth and keep cells from dividing too quickly. When these gene functions are lost, that protection is reduced.

This topic also includes how tumor suppressor genes can be turned off without changing the DNA code itself. Epigenetic changes are chemical changes that affect gene activity. They can silence a tumor suppressor gene and lower its function in the cell.

Understanding tumor suppressor gene loss helps explain one way cancer develops. It shows how a cell can lose important growth control and move toward uncontrolled division.

Tumor Suppressor Gene Loss in Cancer

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cancers originate from somatic mutations in a single cell

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cancer-critical genes ii: tumor suppressor genes

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Tumor Suppressor Genes in Cancer

Tumor suppressor genes help keep cell growth under control and can limit cancer development. These genes act as safeguards by slowing the cell cycle, repairing damage, or triggering cell death when cells are too abnormal to continue dividing. When tumor suppressor genes are changed or lost, cells may divide when they should not. That loss of control can contribute to tumor growth. Understanding how these genes work helps explain why some cells become cancerous while others stay normal. The...

Tumor suppressor gene loss can help cancer cells grow and survive. Tumor suppressor genes normally help control cell growth and keep cells from dividing too quickly. When these gene functions are lost, that protection is reduced. This topic also includes how tumor suppressor genes can be turned off without changing the DNA code itself. Epigenetic changes are chemical changes that affect gene activity. They can silence a tumor suppressor gene and lower its function in the cell. Understanding...

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How Retroviruses Lead to Cancer

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key terms and concepts

Learn how tumor suppressor gene loss reduces cell growth control and how epigenetic changes can silence these protective genes in cancer.

Tumor Suppressor Gene Loss in Cancer | JoVE K12

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SC.912.L.16.7

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Tumor Suppressor Gene Loss in Cancer

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