Your “Do Now” 3/19

• Take a paper from up front• Complete the “Before” section, questions 1-5• Be prepared to share-out

Learning Target

• I can explain how cancer affects an organism and how cancer can be caused.

Notes #4 Cancer

Cancerhttp://www.youtube.com/watch?v=LEpTTolebqo

• Cancer: disease where cells grow and divide uncontrollably fast

• It can affect almost any part of the body

• This happens when the genes that regulate the cell cycle mutate

• After one of these genes has mutated to cause cancer we call it an oncogene

• Cancer cells are no longer differentiated (no special function)

• Normal cells are programmed to stop growing in number but cancer cells DO NOT.

• Instead, they form a tumor (an abnormal clump of tissue)

Loss of Normal Growth Control

Cancer cell division

Fourth orlater mutation

Third mutation

Second mutation

First mutation

Uncontrolled growth

Cell Suicide or Apoptosis

Cell damage—no repair

Normal cell division

Two types of tumors

1. Benign: tumor that stays in one area2. Malignant: tumor that can spread into other

areas

Malignant versus Benign Tumors

Malignant (cancer) cells invade neighboring tissues, enter blood vessels, and move to different sites

Time

Benign (not cancer) tumor cells grow only in one area

Metastasis: process of cancer cells spreading from one area to another

Copyright © 2010 Pearson Education, Inc.

Cancer in People

What types of cancer have we heard of?

Leading Sites of New Cancer Cases and Deaths, 2008 Estimates

Copyright © 2010 Pearson Education, Inc.

4 Common Killers

• Lung Cancer• Breast Cancer• Prostate Cancer (Men only)• Ovarian Cancer (Women only)

Different Kinds of Cancer

LungBreast

(women)

ColonBladder

Prostate (men)

Sarcomas:FatBoneMuscle

Lymphomas:Lymph nodes

Leukemias:BloodstreamCarcinomas:

Stages of cancerStage Definition

Stage 0 Cancer in one particular spot

Stage I, Stage II, and Stage III

Higher numbers indicate more extensive disease: Larger tumor size and/or spread of the cancer beyond the organ in which it first developed to nearby lymph nodes and/or organs adjacent to the location of the primary tumor.

Stage IVThe cancer has spread to another organ(s).

Why is cancer deadly?• Cancer cells take-up nutrients & space• As tumors grow they become harder to

destroy as they affect more cells faster• Tumors can crowd-out and destroy critical

organs

Cancer Death Rates, by Race and Ethnicity, United States,

2000–2004

Copyright © 2010 Pearson Education, Inc.

How do people get cancer?

• Carcinogen: something that causes cancer

Carcinogen Examples• Radiation – X Rays, UV light

• Chemicals – tar from cigarettes

• Virus – HPV can cause cervical cancer.

• Genetics– Some families are more likely to get certain cancers. – Remember you can’t inherit cancer its just that you can be

more likely to get it

Table 13.3

Detecting Cancer– Magnetic Resonance Imaging (MRI)– Computerized Axial Tomography scanning (CAT scan)– Ultrasound– Self-exam and check-ups

MRI for breast examhttp://www.youtube.com/watch?v=S16eUPbZ1Zo

Cancer Treatments• Radiotherapy: Using radiation to destroy tumors• Chemotherapy: Using a drug to destroy

cancerous tissues• Stem cells: Cancerous tissues destroyed, then

replaced with stem cells

Chemotherapyhttp://www.youtube.com/watch?v=XuMPdZjsngQ

Cyberknifehttp://www.youtube.com/watch?v=xYcXRaTvRKc&feature=related

Preventing cancer

• Healthy Diet– Eating foods with antioxidants (fight cancer)– Eat brightly-colored veggies & fruits (good

immune system chemicals)– Low saturated fat (prevent cancer)

• Regular Exercise• Drink Water• Avoid carcinogens!

Current Cancer research• Finding causes• Finding prevention & treatment strategies• Stem-cell use• Gene therapy

Some myths & facts from the Mayo Clinic

• Myth: If we can put a man on the moon, we should have a cure for cancer by now.

• Truth: Finding the cure for cancer is proving to be more complex than mastering the engineering and physics required for spaceflight.

• Myth: Regular checkups and today's medical technology can detect all cancer early.

• Truth: Although regular medical care can indeed increase your ability to detect cancer early, it can't guarantee it. Cancer is a complicated disease, and there's no sure way to always spot it.