Section 1: Cancer

1.1] The chances are that you will know someone affected by cancer, perhaps someone close to you. In the Western World one in three people are affected in some way by cancer. The following well-known personalities have died from cancer: Napoleon Bonaparte, Sigmund Freud, King George IVth, Bobby Moore, Iain Banks, David Bowie. Film and T/V personalities Richard Briers, (The Good Life), Linda Bellingham, (All Creatures Great and Small), Carol Keating (Blue Peter), Alan Rickman, (Professor Snape in eight ‘Harry Potter’ films), Terry Wogan and Victoria Wood (various memorable roles), and music composer Sir Peter Maxwell Davies. Young people can also have cancer, though it is much less common than in older adults. Here are a few thoughts from Amrik who was 18 years old when he was diagnosed with Hodgkin lymphoma (cancer of the lymphatic system).
From: Macmillan Cancer Support. Quotes and image courtesy of Macmillan Cancer Support.
Hodgkin lymphoma is now one of the most curable cancers when diagnosed in young people. Amrik’s cancer affected his lymphatic system and is one of about 200 hundred different types of cancer found in humans. Some cancers are sub-types of ‘organ-named’ ones. For example there are 10 different sub-types of breast cancer and not all sub-types are suitable for treatment in the same way. Amrik, free of cancer did go to university. 1.2] Cancers are found in many living things. Cancerous tumours are found in plants and other animals as well as in humans. Across the globe these include hydra (a two-layered polyp found in fresh water), fish, amphibians, reptiles, birds, mammals (non-human) and in plants (as crown galls). (See section 2. Note 2.2.5) In humans cancers are no respecters of status. In the Western World it is estimated that there is a life-time risk of 1 in 3 for a diagnosis of cancer. Many cancers are more prevalent in older people simply because over the years more mutations will have happened. Some cancers are more prevalent in some countries due to external factors such as food type and sun exposure. Different demographic groups also show differences, again due mainly to external factors including education, cheaper/poorer food, obesity and exposure to work-place mutagens. Females and males have different cancers of sex organs but other cancers are common to both sexes. We will look at the biology of cancer in slightly more detail. During this journey it will be useful to keep in mind the main ideas of ecology, Darwinian style evolution and cell signalling and communication. 1.3] A special message to viewers who are studying Biology at ‘AS’/‘A’ level [in England] or equivalent courses elsewhere. Aspects of cancer biology are listed in several of the ‘A’ level specifications laid down by some of the examination organisations (e.g. OCR, AQA). We hope you find all these e-learning pages informative, interesting and useful but if you only have limited time you will find LEVEL 1 of each section provides brief information; more detail is given at LEVEL 2. Information about some genes listed in examination specifications can be found at the end of Section 3 level 2. Graphic 8 provides information about BRCA 1, BRCA 2 and p53 genes. Graphic 9 shows information about RAS and MYC genes. Please note some of the information provided is very new and will not be in textbooks. Be careful how you use it, especially in exams. We wish you well with your study of biology and hope that one day some of you will help in cancer research, nursing or medicine. Despite advances there is still much to learn. Some links form this website show examples of work being undertaken. Good luck!