CELL BIOLOGY AND CANCER

.01 Cancer types, incidence, pre-disposition, and risk factors

CANCER WHERE DID IT GET ITS NAME?

Hippocrates observed 2300 years ago that the long, distended veins that radiate out from some breast tumors look like the limbs of a crab – from that observation came the term KARKINOMA in Greek, and later, CANCER in Latin.

A. Cancer facts Group of 100 diseases that develop across time

2. Can develop in virtually any of the body’s tissues

3. Characterized by uncontrolled cell division

4. Hereditary & environmental factors contribute to cancer development

5. Second leading cause of death in U.S.

6. Men have one in two lifetime risk, women one in three ACTIVITY 1 – FACES OF CANCER

Type of Information FAMILY HISTORY (write in the number of “yes” and “no” answers for all teams) YES _____ NO ______

NUMBER OF PEOPLE DIAGNOSED WITH CANCER TOTAL OF ALL TEAMS 0-19 YEARS _____ 20-39 YEARS ______ 40-59 YEARS ______ 60 AND OLDER ______

TYPE OF CANCER WRITE IN THE NUMBER OF EACH BLADDER __ LEUKEMIA __PROSTATE ___ BRAIN ___ LUNG ___ RETINOBLASTOMA ___ BREAST ___ ORAL CAVITY ___ SKIN ___ CERVICAL ___ OVARIAN ___ UTERINE ___ COLON ___ PANCREATIC __ OTHER ___

POSSIBLE RISK FACTORS (LIST ANY POSSIBLE RISK FACTORS)

B. Types of cancer Benign – not cancerous, does not invade nearby tissue or spread to other parts of the body (will grow & push organs out of way) Malignant – cancerous; can invade nearby tissue and spread to other parts of the body (will invade organs by enzymes eating through tissue)

Metastatic – spread through body by hemogenic (blood) or lymphogenic (lymph)

4. Type depends on cause & location 5. Each type has its own growth rate, prognosis, and treatability

C. Incidence increases with age (old men have better chance of developing cancer) Develops over time and could result from different causes Can occur at any age and in any location

D. Inherited predisposition Can inherit a cancer – susceptible mutation Occurs in all the body’s cells

E. Risk Factors Increase a person’s risk for developing cancer Cigarette smoking Exposure to the sun Exposure to carcinogens Females – family history of breast cancer Fair skin Chemicals, radiation, & viruses

Risk Factors We Can Control ~Excessive exposure to UV radiation especially for those with fair complexion ~Occupational exposure to substances like coal tar, creosote, arsenic compounds & radium ~Poor nutrition & improper body weight ~Risky sexual behavior ~Substance abuse ~Prolonged exposure to stress

Risk Factors We Cannot Control ~ Aging (Which is one of the biggest risk factor) ~ Males are more likely than females to develop cancer ~ Heredity (Inherited Predisposition)

F. Chance of surviving cancer increases with early detection & treatment Incidence rate – number of new cases per year per 100,000 persons Mortality rate – number of deaths per 100,000 persons per year Survival rate – proportion of patients alive at some point after their diagnosis of cancer (chance of cure) Morbidity - disease

.02 Causes & development of cancer Many different agents can cause cancer (Carcinogens) sun Radiation Chemicals smoking

Cancer involves the uncontrolled division of body cells. B. Cancer represents a breakdown of the processes that regulate the growth of normal cells & tissues. Cancer involves the uncontrolled division of body cells. Cell division is normally precisely regulated Cell cycle regulation is accomplished by two major types of genes

4. Cancer causing agents often damage genes 5. When damage occurs to genes that regulate the cell cycle, signals that inhibit cell division can change leading the cell to divide more often that it normally would (cancer cells multiply rapidly, taking up space and nutrients from the normal cells

C. Cancer develops from genetic damage to cells across time Cigarette smoke can damage genes that regulate growth of normal cells

D. Cancer research leads to understanding normal cell cycle and new strategies for treating cancer

E. Stages of tumor development tumor – mass of cancer cells adenoma – noncancerous tumor Ovarian mucinous cyst adenoma This tumor weighed 35 pounds.

1. Mutation – damage to genes causing cells to alter (1st stage of tumor development) 2. Hyperplasia – altered cells & its descendents grow & divide too often

3. Dysplasia – one of these cells experiences another mutation that further increases its tendency to divide. This cell’s descendents divide excessively & look abnormal

4. In situ (tumor) – Tumor formed from these mutated, rapidly dividing cells stays contained within its tissue of origin

5. Invasive cancer (malignant) – if some cells experience additional mutations that allow the tumor to invade neighboring tissues & shed cells into the blood or lymph, the tumor is malignant.

6. Metastases – escaped cells may establish new tumors at other locations in body

Cancer has been described as a single disease and a hundred diseases Single disease – all cancers display uncontrolled growth, the ability to expand without limit. Hundred diseases – cancer can appear as a result of different causes, in a variety of sites within the body, and that each type of cancer displays its own growth rate, prognosis, and treatability.

The discovery that all cancer involves a fundamental disruption in the growth of cells and tissues suggests that to understand cancer, we need to understand the events and processes that occur as both normal and abnormal cells grow and divide.

In fact, much cancer research across the past two decades has focused on this challenge. This research has revealed a complex picture of how two classes of genes, called proto-oncogenes and tumor suppressor genes, normally regulate the intricate sequence of cell cycle events.

And it also has revealed how the accumulation of mutations in these genes can contribute to the development of an altered cell, a cell that has lost the normal controls on cell division. Activity 2

.03 Genetic damage & mutation Cancer results from the accumulation of genetic damage to cells across time multiple exposure over time Mutation causes change in the way the cell functions or develops

B. Cancer cells differ from normal cells Shape changes (appearance changes) Changes in their dependence on growth factors Multitude of biochemical differences

Know the ABCDs of early detection Learn your ABCDs, the changes in a mole or skin growth that are warning signs of melanoma: Asymmetry: One half doesn't match the other half. Border Irregularity: The edges are ragged, notched, or blurred. Color: The pigmentation is not uniform. Shades of tan, brown, and black are present. Dashes of red, white, and blue add to the mottled appearance. Color may spread from the edge of a mole into the surrounding skin. Diameter: The size of the mole is greater than 6 mm (0.2 in.), or about the size of a pencil eraser.

C. Cancer is a multi-step process, which explains: Increased incidence of cancer with age Development of cancer decades after exposure to carcinogens (severe sunburns as a child) Increased incidence of cancer among people with inherited dispositions (they are more likely to develop cancer than the general population) Activity 3

.04 Improve personal and public health A. Good choices can reduce an individual’s risk of developing cancer 1. Levels of cancer prevention A. Individual behavior changes – develop healthy behavior habits B. Health care providers – perform counseling & routine screening

c. National level – government regulations to minimize public exposure to known carcinogens d. International level – actions of developed countries bring cancer worldwide

2. Attention to ethical & public policy issues Children wear protective headwear & clothing during peak hours of UV exposure would prevent most skin cancers

B. Risk factors for skin cancer Excessive exposure to UV (ultraviolet) radiation – damages skin cells Fair complexion Occupational exposure to substances Known carcinogens: a. coal tar b. Creosate c. Arsenic Compounds d. Radium

C. Good choices can improve an individual’s chance of survival if he/she develops cancer Improved detection Improved treatment Activity 4

Early Detection Cancer remains the 2nd leading cause of death in the United States. Cancer is a multi-stage disease. The earlier stages of the disease are now more manageable and curable.

Breast cancer screening The type and frequency of breast cancer screening that is best for you changes as you age. Ages 18 to 39: You should have a clinical breast exam every 3 years. If you have a high risk for developing breast cancer, talk to your health professional about when to begin having annual mammograms. Ages 40 to 69: Annual clinical breast exams are recommended by all experts for women in this age group.

Cervical cancer screening The Pap test is the most effective screening test for cervical cancer and is often part of a pelvic exam. Testing should start within 3 years of a woman beginning sexual intercourse, whatever age that may be, but no later than 21 years of age. Women older than 30 should have different screening recommendations based on their risk factors.

Testicular and Prostate cancer screening The American Cancer Society (ACS) recommends that all men between the ages of 15 and 40 have a testicular exam as part of a regular physical exam by their health professionals. Prostate exams are part of regular physical exams which should be done annually. A blood test called PSA (Prostate Specific Antigen) is available now and can detect the presence of prostate cancer earlier than physical exam. It is generally recommended for men over age 50 or those with risk factors for the disease.

Skin cancer screening Screening guidelines from the American Cancer Society and other expert groups recommend that adults older than 40 have their skin checked by a health professional at least once a year, as well as during any other health exam.

Colon and rectal cancer screening After age 50 the recommendations include annual screening of stool for occult blood. Colonoscopy, sigmoidoscopy and/or barium enema once every 5 years or as recommended by your health professionall.

Look for any abnormal skin growth or any change in the color, shape, size, or appearance of a skin growth. Check for any area of injured skin (lesion) that does not heal. Have your spouse or someone such as a close friend help you monitor your skin, especially places that are hard to see such as your scalp and back.

People People of all ages should get to know their skin People People of all ages should get to know their skin. of all ages should get to know their skin. Skin self-exam is a good way to detect early skin changes that may indicate melanoma, because most primary melanomas are easily seen on the surface of the skin. Skin cancer often appears on the trunk of men and on the legs of women.

Awareness of Treatment Options Seek education and stay current about new research and discoveries on your own by reading, listening and asking questions.

Ethics is a process of rational inquiry D. Ethical values sometimes conflict in public policy debated about strategies for reducing the risk of cancer Ethics is a process of rational inquiry Ethics requires a solid foundation of information & careful interpretation of that information

Public policy may invade an individual’s freedom and autonomy 3. There are often competing, well-reasoned answers to what is right & wrong, or good or bad Ex: Public policy may invade an individual’s freedom and autonomy Banning smoking in public places Activity 5

A PROPOSED STATUTE MANDATORY USE OF SKIN PROTECTION FOR ALL INDIVIDUALS UNDER THE AGE OF 18 Whereas it is well documented that only 15 percent of Americans regularly wear a sunscreen when they are outside, and 25 percent never wear sunscreen.

Whereas there is a direct link between the sun’s ultraviolet (UV) rays and melanoma, the deadliest form of skin cancer. Whereas there were more than 42,000 new cases of malignant melanoma diagnosed in 1999. Whereas more than 7,000 Americans die each year from melanoma.

Whereas disruption of the earth’s ozone layer by atmospheric chemical pollution may lead to rising levels of UV radiation. Whereas 80 percent of a person’s UV exposure occurs prior to age 18. Be it enacted by the Federal Statues that:

All individuals under the age of 18 are required to wear headgear and clothing that covers 90 percent of the extremities while outside during peak hours of UV exposure. This covering shall occur in all public locations that are currently under federal jurisdiction, including public school property, recreation sites, federal buildings, and work sites supervised by employers that are overseen by OSHA regulations.