Cancer ppt

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Cancer

– unregulated cell growth

https://www.youtube.com/watch?v=46Xh7OFkkCE

Detecting & Treating _{https://www.youtube.com/watch?v=}

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Cancer – uncontrolled cell division

Normal Cell

• Anchorage dependence

• Contact inhibition

• Checkpoints observed

• Tumor suppressor &

proto-oncogenes functioning properly

• Set life span (# of

divisions) - apoptosis

Cancer Cell

• Can metastasize

• Invades surrounding

tissue

• Angiogenesis

• Ignores checkpoints

• Mutations in tumor

suppressor & proto-oncogenes (become oncogenes)

• “immortal” – no set life

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Cancer results from mutations in genes that

control cell division

• Cancer is a set of diseases in which the control mechanisms that normally limit cellular growth have malfunctioned.

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11.15 Cancer results from mutations in genes

that control cell division

• The genes that a cancer-causing virus inserts into a host cell can make the cell cancerous.

• Such a gene is called an oncogene (from the Greek onco, tumor).

https://www.youtube.com/watch?v=2wIVwZksIt4

• Over the last century, researchers have identified a number of viruses that harbor cancer-causing

genes.

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11.15 Cancer results from mutations in genes that control cell division

• Mutations in two types of genes can cause cancer.

1. Oncogenes

• Proto-oncogenes are normal genes that promote cell division.

• Mutations to proto-oncogenes create cancer-causing

oncogenes that often stimulate cell division. 2. Tumor-suppressor genes

• Tumor-suppressor genes normally inhibit cell division or function in the repair of DNA damage.

• Mutations inactivate the genes and allow

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Growing out of control, cancer cells produce

malignant tumors

• Cancer currently claims the lives of 20% of the people in the United States.

• Cancer cells escape controls on the cell cycle.

• _{Cancer cells divide excessively and invade other} tissues of the body.

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• _A_tumor_{is a mass of abnormally growing cells} within otherwise normal tissue.

• Benign tumors remain at the original site but may disrupt certain organs if they grow in size.

• Malignant tumors can spread to other locations in a process called metastasis.

• An individual with a malignant tumor is said to have

cancer.

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Tumor

Glandular tissue

Tumor growth Invasion Metastasis

Lymph vessels Blood vessel

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• Localized tumors can be

• removed surgically and/or

• treated with concentrated beams of high-energy radiation.

• Metastatic tumors are treated with chemotherapy.

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Introduction to Immunotherapy

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Tailoring treatment to each patient may

improve cancer therapy

• It is increasingly possible to personalize cancer treatment by

• sequencing the genome of tumor cells and

• _{tailoring treatment based upon the tumor’s specific}

genetic profile.

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11.16 Multiple genetic changes underlie the

development of cancer

• More than 100,000 Americans will be stricken by cancer of the colon this year.

• Colon cancer is one of the best-understood types of human cancer and illustrates an important

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• Colon cancer illustrates the gradual progression from somatic mutation to cancer.

1. An oncogene arises or is activated, resulting in increased cell division in apparently normal cells in the colon lining.

2. Additional DNA mutations cause the growth of a small benign tumor (polyp) in the colon wall.

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© 2015 Pearson Education, Inc. Figure 11.16a-3 Colon wall 2 1 3 DNA changes: An oncogene is activated Cellular changes: Increased cell division A tumor-suppressor gene is inactivated

Growth of a polyp (benign tumor)

A second tumor-suppressor gene

is inactivated

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Figure 11.16b

Normal cell

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CONNECTION: Lifestyle choices can reduce

the risk of cancer

• After heart disease, cancer is the second-leading cause of death in most industrialized nations.

• Cancer can run in families if an individual inherits an oncogene or a mutant allele of a

tumor-suppressor gene that makes cancer one step closer.

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• Carcinogens are cancer-causing agents that alter DNA.

• Most mutagens (substances that promote mutations) are carcinogens.

• Two of the most potent carcinogens (mutagens) are

• X-rays and

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• The one substance known to cause more cases and types of cancer than any other single agent is tobacco.

• More people die of lung cancer than any other form of cancer.

• Although most tobacco-related cancers come from smoking, passive inhalation of second-hand smoke is also a risk.

• _{Tobacco use, sometimes in combination with}

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• Healthy lifestyles that reduce the risks of cancer include

• avoiding carcinogens, including the sun and tobacco products,

• exercising adequately,

• regular medical checks for common types of cancer, and

• _{a healthy high-fiber, low-fat diet including plenty of}