Journal

Cancer: Uncontrolled Cell GrowthHow do cancer cells differ from other cells?

Cancer cells do not respond to the signals that regulate the growth of most cells. As a result, the cells divide uncontrollably.Review!Cells divide only when they receive the proper signals from growth factors that circulate in the bloodstream or from a cell they directly contact.

For example, if a person loses blood, a growth factor called erythropoietin which is produced in the kidneys circulates in the bloodstream and tells the bone marrow to manufacture more blood cells.When a cell receives the message to divide, it goes through the cell cycle which includes several phases for the division to be completed. Checkpoints along each step of the process make sure that everything goes the way it should.

Many processes are involved in cell reproduction and all these processes have to take place correctly for a cell to divide properly. If anything goes wrong during this complicated process, a cell may become cancerous .CancerUncontrolled Cell Growth

A disorder in which body cells lose the ability to control cell growth.

Cancer CellsCancer cells do not respond to the signals that regulate the growth of most cells. As a result, the cells divide uncontrollably.

Cancer cell-Cell that grows out of control

Ignore signals to stop dividing, to specialize, or to die and be shedCancer CellsHave defects in normal cellular functionsGrowing in an uncontrollable manner and unable to recognize its own natural boundary, the cancer cells may spread to areas of the body where they do not belong. In a cancer cell, several genes change (mutate) and the cell becomes defective.

What is a tumor?Cancer cells divide uncontrollably to form a mass of cells called a tumor.

What causes cancer?Cancers are caused by defects in genes that regulate cell growth and division.

Some sources of gene defects are smoking tobacco, radiation exposure, defective genes, and viral infection.

A damaged or defective p53 gene is common in cancer cells. It causes cells to lose the information needed to respond to growth signals.

MetastasizeTo transmit microorganisms or cancerous cells from an original site to one or more sites elsewhere in the bodyTreatmentTreatment will vary depending on many different factors associated with both the type of cancer & the patient.Some localized tumors can be removed by surgery.

Many tumors can be treated with targeted radiation.

Chemotherapy is the use of compounds that kill or slow the growth of cancer cells.

Benign Tumors that do not grow in an unlimited, aggressive manner, do not invade surrounding tissue, and does not metastasizeA benign tumor is noncancerous. It does not spread to surrounding healthy tissue.

MalignantNot self-limited in its growth and is capable of invading into adjacent tissues

A malignant tumor is cancerous. It invades and destroys surrounding healthy tissue and can spread to other parts of the body.May be capable of spreading to distant tissues metastasisThe process of transmission of cancerous cells from an original site to one or more sites elsewhere in the body

Cancer cells absorb nutrients needed by other cells, block nerve connections, and prevent organs from functioning.

Cancer is named for its site of originEx>breast cancer that spreads to the lungs and forms a metastatic tumor is metastatic breast cancer, not lung cancer.

Types of CancerOsteosarcomaMost common type of bone cancerAffects 2x as many males as femalesTends to show up in people who are taller than averageLeukemiaOne of the most common childhood cancers

Occurs when large numbers of abnormal white blood cells called leukemic blasts fill the bone marrow & sometimes the blood stream

Because these abnormal blood cells are defective, they don't help protect the body against infection the way normal white blood cells do.

And because they grow uncontrollably, they take over the bone marrow and interfere with the body's production of other important types of cells in the bloodstream, like red blood cells (which carry oxygen) and platelets (which help blood to clot).Brain TumorsNo one knows the exact cause

If it is possible to remove a tumor, surgery is usually performed, followed by radiation. Some patients receive chemotherapy as well. Survival depends on type, location & treatment LymphomaCancer that develops in the lymphatic system (the lymph nodes, thymus, spleen, adenoids, tonsils, and bone marrow.

Most teens with lymphoma have either: Hodgkins disease or Non-Hodgkins lymphomaHodgkins DiseaseOccurs in adolescent and young adults

Shows up in lymph nodes in neck, armpits etc.

Lymph nodes are usually enlarged but not painfulNon-Hodgkins LymphomaSimilar to leukemia because both might involve malignant lymphocytes (white blood cells ) and symptoms are similarSkin CancerBasal Cell CarcinomaMost common cancer in humansAppears as a shiny translucent or pearly noduleMost appear on skin with a history of exposure to the sunSquamous Cell CarcinomaBegins in the squamous cellsTends to develop in fair-skinned middle-aged & elderly people who have had long term sun exposure30MelanomaBegins in cells within the epidermis that give skin its color Most lethal form of skin cancerBreast Cancer Cancer that starts in the cells of the breast in men & womenLung CancerA disease of uncontrolled cell growth in tissues of the lung

Most common symptoms are: shortness of breath, coughing, and weight loss

the most common cause of cancer-related death in men and the second most common in women, is responsible for 1.3 million deaths worldwide annually.Prostate CancerA disease in which cancer develops in the prostate, a gland in the male reproductive system. These cells may spread (metastasize) from the prostate to other parts of the body, especially the bones and lymph nodes.

Most frequently in men over 50Many men who develop this cancer never have symptoms, undergo no therapy, and eventually die of other causes

Colon CancerCancer of the large intestine (colon), the lower part of your digestive system