CANCER

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CANCER

• A. Characteristics of Cancer Cells
• 1. Structural Abnormalities
• a. Has an abnormal large nucleus and
  less cytoplasm then usual
• b. Poorly differentiated
• c. When the transformed cell divides, its
  daughter cells are cancerous cells too.

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• 2. Uncontrolled Growth
• a. Normal cells - contact inhibition
• Cancerous cells no contact inhibition. As a
  result, cancer cells pile up in a
  disorganized
• lump.
• b. Lack cell-to-cell adhesion with neighboring
  cells. They may form extensions
  (pseudopodia) that enable them to move
  about (metastasis) malignant.

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• c. Some cancer cells produce interleukin 2,
  which stimulates cell division and also
  display receptor for it
• d. Cancer cells secret a growth factor,
  angiogenin, encourage new blood vessels to
  grow around the tumor.

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• B. Carcinogenesis the onset of cancer
• Proto-oncogenes are normal genes that
• regulate cell growth and development .
• They may change their structure or
  expression, they may become oncogenes.
  
• Oncogenes a DNA segment that can cause
  caner.
• a mutated gene that can help make a cell
• cancerous
• genes normally turns ON cell growth or
  division

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• MUTATIONS
• DNA ( deoxyribonucleic acid) change and can
  transmitted from one generation to another.
• Caused by mutagens. Results from
• normal metabolism (free radicals),
• chemicals (mutagens/pollutants),
• radiation (sunlight, chemicals),
• genetic translocations, disorders.

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• Onset of malignant cancer requires mutations in
  several genes
• Tumor suppressor gene prevent cancer from
  occurring
• e.g. p53 a very important tumor suppressor gene
  can prevent change. Mutated p53 genes found in
  cancers of breast, bone, colon, skin, lung,
  bladder, cervix, and brain.
• Oncogen Activation
• When there is mutation, triggers expression of
  oncogen.

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• Other Routes to Carcinogenesis
• 1. Inherited Susceptibility to Cancer
• 2. Viruses
• DNA tumor viruses
• RNA tumor viruses
• 3. Chemical Carcinogens
• By-products of the industrialization of human
  societies
• e.g. asbestos, coal tar, benzene, hydrocarbons
  in cigarette smoke, and some pesticides.
• 4. Radiation
• X-ray, UV and some radioactive materials cause
  mutation

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• C. Some Major Types of Cancer
• Cancer is categorized according to the tissue in
  which it arises
• Sarcomas connective tissues
• Carcinomas epithelium
• Adenocarcinomas glands or its ducts
• Lymphomas lymphoid tissue
• Leukemia blood forming regions such as bone
  marrow

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Things we can do that may lower our risk of
developing cancer

• Drink green tea
• Cook with olive oil
• Eat garlic
• Eat fruit and vegetables, which are rich in
  anti-oxidants
• Exercise/stimulate immune system
• Use sun tan lotion, avoid getting burned