CELL DIVISION GONE WILD! Cancer CELL DIVISION GONE WILD! 1

The Reasons for Cancer Cancer occurs when: cells divide uncontrollably abnormally grown cells interfere and disrupt other cell functions & take in other cell’s nutrients and food Mutations occur in the genes that control cell division. Mutations are cells with changes to their DNA. 2

Skin Cancer 3

Skin Cancer 4

Properties of Cancer Cells reproduce in defiance of the normal restraints: don’t stop at the checkpoints in the cell cycle lack cell-to-cell adhesion (contact inhibition) signals resist to cell “suicide” signals (apoptosis)

Properties of Cancer Cells grow & form a lump; sometimes called a tumour (neoplasm) Invade & colonize territories normally reserved for other cells quickly alternate shape between round & elongated

Who gets cancer? 1 in 3 people will develop cancer during their lifetime Cancers can occur at any age, but the risk of developing cancer increases with age. Over 70% of all newly diagnosed cancers occur in people aged 60 years or more. 7

Causes of Cancer Genetics Age Spontaneous mutation Stress Chemical carcinogens Radiation Most cancers result from avoidable combinations of environmental causes

Causes for Cancerous Mutations Viruses - some viruses interfere with cell division by inserting their own DNA Radiation - high energy radiation like ultraviolet light and X-rays have been linked to skin cancer Chemicals - cigarette smoke and smog have been linked to lung cancer 9

Causes of Cancer Everyday life choices to reduce risks of cancer development: Be a non-smoker & avoid tobacco smoke. Eat a healthy diet. Be physically active every day. Stay at a healthy weight. Limit alcohol use. Reduce your exposure to UV (ultraviolet) rays from the sun or tanning beds. Know your body & report any changes to your doctor or dentist. Follow health & safety instructions when using hazardous materials at home or work.

Types of Cancer Carcinomas – About 85% of cancers are carcinomas. They start in the covering (or lining) of organs and of the body (the skin). Sarcomas – These form in the connective tissues of the body such as muscle, bone and fatty tissue (6% of cancers). Leukaemias/Lymphomas – These occur in the tissues where white blood cells (which fight infection in the body) are formed, i.e. the bone marrow, and lymphatic system (5%). Others forms of cancer – Brain tumours and other rare forms of cancer make up the other 4% of cancers

Lung Cancer 12

Brain Cancer 13

Oral Cancer 14

Formation of a Tumour Mutation and initial mild disorder of cell behaviour cause a normally dividing cell to divide erratically As the abnormally dividing cells form the tumor, they stimulate the development of blood vessels (angiogenesis) for oxygen and nutrients

Cancer and the Cell Cycle tumour – an abnormal clump of cells formed when cells divide repeatedly and excessively 16

Cancer and the Cell Cycle Cancer – cells with abnormal genetic material that are dividing uncontrollably and can spread to other parts of the body Malignant tumours – (cancerous) invade and destroy nearby tissue and spread to other parts of the body Benign tumours – (non-cancerous) may grow larger but do not spread to other parts of the body

Tumours Malignant tumours: can be deadly. Parts of these tumours can break off and spread throughout your body depositing new tumours, perhaps in vital organs. cells of the tumour break lose, enter the bloodstream or lymphatic vessels and form secondary tumours (metastases)

Cancer and the Cell Cycle Cancer Development

Metastasis Cells break away from the original (primary) cancer & spread to other organs in the body by travelling in the bloodstream or lymphatic system. When these cells reach a new area of the body they continue dividing & form a new tumour, often referred to as a "secondary" or a "metastasis".

Cancer Treatments Or a combination of all 3. 1. Surgery: tumour is surgerically cut out. 2. Radiation Therapy: radiation is used to kill the tumour cells 3. Chemo Therapy: Toxic chemicals are attempt to poison the cancer cells (stop mitosis). Or a combination of all 3. 21

Carcinogens asbestos tobacco smoke or drinking alcohol human papilloma virus (HPV) pesticides

Melanoma Dear 16 year old me 23

REAL LIFE CANCER From one of your peers… 24

Cancer growth http://www.youtube.com/watch?v=j_wRpa2b5XI http://www.ted.com/talks/william_li.html 25