Causes and Development of Cancer

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Causes and Development of Cancer
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Causes and Developments of Cancer

• Many different agents can cause cancer

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Causes and Development of Cancer

• Cancer represents a breakdown of the processes
  that regulate the growth of normal cells and
  tissues.

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Causes and Development of Cancer

• 1. Cancer involves the uncontrolled division of
  body cells.
• 2. Cell division is normally precisely regulated

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Causes and Development of Cancer

• 3. Cell cycle regulation is accomplished by two
  major types of genes
• 4. Proto-oncogenes are genes that encourage cell
  division

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Causes and Development of Cancer

• 5. Tumor suppressor genes inhibit cell division

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Causes and Development of Cancer

• 6. Cancer-causing agents often damage genes.
• .

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Causes and Development of Cancer

• 7. When damage occurs to genes that regulate the
  cell cycle, signals that inhibit cell division
  can change leading the cell to divide more often
  than it normally would

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Causes and Development of Cancer

• 8.Cancer develops from genetic damage to cells
  across time

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Causes and Development of Cancer

• 9. Cancer research leads to understanding normal
  cell cycle and new strategies for treating cancer.

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Vocabulary Help

• Plasia means formation

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Stages of Tumor Development1. Mutation

• Makes a cell more likely to divide then it
  normally would

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Stages of Tumor Development2. Hyperplasia

• Hyperplasia refers to tissue growth based on an
  excessive rate of cell division,
• Cell structure and the arrangement of cells
  within the tissue remain normal
• At some point one of these cells will have
  another mutation (2) that makes it divide more

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Stages of Tumor Development2. Hyperplasia

• Hyperplasia can be a normal tissue response to
  an irritating stimulus
• Example Callus
• Condition is still reversable

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Stages of Tumor Development3. Dysplasia

• Noncancerous
• Divide excessively and look abnormal
• One of these cells will experience another
  mutation (3)

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Stages of Tumor Development3. Dysplasia

• Often such cells revert back to normal behavior,
  but occasionally they gradually become malignant
• Potential for becoming malignant so these areas
  should be closely monitored by a health
  professional
• Sometimes they need treatment

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Stages of Tumor Development4. In situ cancer
(tumor)

• Cell and its descendants are very abnormal in
  both growth and appearance
• In Latin, the term "in situ" means "in place," so
  carcinoma in situ refers to an uncontrolled
  growth of cells that remains in the original
  location.

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Stages of Tumor Development4. In situ cancer
(tumor)

• May remained contained indefinetely
• May develop into an invasive, metastatic
  malignancy
• Is usually removed surgically, if possible

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Stages of Tumor Development5. Invasive Cancer
(Malignant)

• Happens if some cells experience more mutations
  and invade neighboring tissues.
• Sheds cells into blood and lymph
• Tumor is said to be malignant
• New tumors may metastasize to other locations in
  the body

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The End