Biology of cancer and treatme Done by:Tumadhir jilani To: Dr:sabah
Index-Introduction.-The characteristics of cancer.-Cancer is genetic disease.-Types of cancer genes.-What causes cancer?-Carcinogens.-Benign and malignant.-Cancer treatment and prevention.
Introduction of cancerThe division of normal cells is preciselycontrolled. New cells are only formed forgrowth or to replace dead ones.Cancerous cells divide repeatedly out ofcontrol even though they are not needed,they crowd out other normal cells andfunction abnormally. They can alsodestroy the correct functioning of majororgans.
The Characteristics of CanceAs genes switch on and off, theydetermine when and how fast the cell willgrow and divide, when it will stopdividing, and even when it will die.Cancer can result when controls over celldivision are lost…
Cancer is a Genetic DiseasCancer is a genetic disease that developsin a predictable sequence of steps.. Carcinogenesis • Transformation of a normal cell into a cancerous cell. • Step-by-step transformation.
A Common Type of ColorectalCancer May Develop by TheseSteps
Types of cancer genesType of gene Normal function Mutated function Types of proteins PromotesOncogene Promotes division - Growth factors division abnormal time or cell typeTumor Suppresses Fails to Checkpointsuppressor cell division suppress moleculesgene divisionDNA repair Enzymes for Repair DNA Fail to repairgene mismatch or mutations DNA mutationsmutation excision repair
What causes cancer?Cancer arises from the mutation of anormal gene.Mutated genes that cause cancer arecalled oncogenes.It is thought that several mutations needto occur to give rise to cancer.Cells that are old or not functioningproperly normally self destruct and arereplaced by new cells.However, cancerous cells do not selfdestruct and continue to divide rapidlyproducing millions of new cancerous cells.
A factor which brings about a mutation iscalled a mutagen.A mutagen is mutagenic.Any agent that causes cancer is called acarcinogen and is described ascarcinogenic.So some mutagens are carcinogenic…
carcinogens-Ionising radiation – X Rays, UV light.-Chemicals – tar from cigarettes.-Virus infection – papilloma virus can beresponsible for cervical cancer.-Hereditary predisposition – Somefamilies are more susceptible to gettingcertain cancers.
Other Factors Also May Lead to CancBreakdowns in immunityHealthy immune system can targetand destroy cancer cells.When cancer cells have alteredproteins at its surface, cells are notdestroyed.Risk of cancer increases: -With age. -When an immune system has been suppressed for a long time. -HIV infection. -Immunosuppressant drugs. -Anxiety and depression.
Benign and malignant?Benign tumours do not spread from theirsite of origin, but can crowd out (squash)surrounding cells eg brain tumour, warts.Malignant tumours can spread from theoriginal site and cause secondarytumours. This is called metastasis. Theyinterfere with neighbouring cells and canblock blood vessels, the gut, glands, lungsetc.Both types of tumour can tire the bodyout as they both need a huge amount ofnutrients to sustain the rapid growth anddivision of the cells.
Some Major Types of CanceIn general, a cancer is named according to thetype of tissue in which it first forms Sarcomas: cancer of connective tissue Carcinomas: cancer arising from epithelium Lymphomas: cancer of lymphoid tissue Leukemias: cancer of stem cells Gliomas: cancer of brain glial cells
Cancer Treatment and PreventioWhen a person is diagnosed with cancer, avariety of weapons are available tocombat it: Chemotherapy drugs Radiation therapy Surgery And other….
ChemotherapyDrugs used to kill cancer cells; disrupt someaspect of cell division.Toxic to healthy cells; hair, bone marrow,lymphocytes, and epithelial cells of intestinallining .Side effects include hair loss, nausea, vomiting,and reduced immune responses.
Radiation therapyIn radiotherapy, high-energy rays are usedto kill cancer cells and stop them fromgrowing and dividing. Like surgery,radiotherapy is a local treatment; it canaffect cancer cells only in the treated area.Radiotherapy is usually given on anoutpatient basis, 5 days a week, forseveral weeks. Patients are notradioactive during or after treatment.
The most common side effects aretiredness, skin reactions such as rash orredness, and loss of appetite. Radiationtherapy may also cause a temporarylowering of the white blood cell count,cells that help protect the body againstinfection. The side effects are usuallytemporary, developing gradually over theweeks of the treatment, and improvinggradually after treatment is completed.
Surgery therapySurgery is the primary method oftreatment of most isolated solid cancersand may play a role in palliation andprolongation of survival. It is typically animportant part of making the definitivediagnosis and staging the tumor asbiopsies are usually required. In localizedcancer surgery typically attempts toremove the entire mass along with, incertain cases, the lymph nodes in thearea. For some types of cancer this is allthat is needed for a good outcome.
Hormone therapySome types of cancer, for example, breastcancer and prostate cancer, depend onhormones to grow. For this reason,doctors may recommend therapy thatprevents cancer cells from getting or usingthe hormones they need. Sometimes, thepatient has surgery to remove the organs(like the ovaries or testes) that make thehormones. Or drugs are used to stophormone production or change the waythe hormones work.
Hormone therapy may cause nausea,swelling of the limbs or weight gainthrough water retention. In women, theremay be irregular periods and vaginaldryness. In men, there may be impotenceor loss of sexual desire.
Biological TherapyBiological therapy, also calledimmunotherapy, uses the bodys ownimmune system to fight infection anddisease or protect the body from some ofthe side effects of other forms oftreatment. Monoclonal antibodies,interferon, interleukin-2, and colony-stimulating factors such as GM-CSF and G-CSF, are forms of biological therapy.
These treatments often cause temporaryflu-like symptoms such as fever and chills,muscle aches and weakness, loss ofappetite and diarrhoea.
Good Lifestyle Choices Can Limit Cancer Risk-Avoid tobacco completely.-Maintain a desirable weight; eat a low-fatdiet with plenty of fruits and vegetables.-Avoid alcohol .-Make sure your living and workenvironment is safe from carcinogens.-Protect your skin from the sun’s UV rays.
finally. Remember you can’t inheritcancer its just that you maybemore susceptible to getting it. sobe careful and prevent yourself…….