CELL DIVISION AND CANCER

Unit 7 - Mitosis

Mitosis

All cells in your body divide In children and teens, cells divide to assist

in growth In adults, cells divide to replace old cells

Your cells are really good at knowing when they should and shouldn’t divide

Cell Regulators

Inside and on the outside of your cells, you have “regulators” that control cell division.

These regulators act as body guards for the cell, making sure that everything goes according to plan

Internal Cell Regulators

These are proteins that respond to events inside the cell.

Example Make sure mitosis doesn’t happen until

chromosomes are replicated

External Cell Regulators

Proteins that respond to events that happen outside the cell

Examples Speed up or slow down cell division Proteins on neighbor cells can tell the cells

around them to stop growing or to slow down so that they don’t impede other tissue or cells.

What is Cancer?

Cancer is a disorder in which some of the body’s own cells lose their ability to regulate cell growth.

Cancerous cells do not respond to the signals from other cells that tell them to stop or slow down their growth.

When the cells do not stop dividing, a tumor is formed.

Benign and Malignant Tumors Benign Tumors

Non-cancerous tumors Cysts Keloids

Malignant Tumors Cancerous tumors

Here, bad cells (those that cannot stop dividing) break off into your blood or lymph systems and travel to other parts of the body. There, they infect the cells around them, causing mass division of cancer cells.

Invasion and Metastasis

Fact

According to the American Cancer Society, in 2012 there have already been 65, 750 new cases of cancer reported.

4 Basic Types of Cancer

Carcinoma Cancer that begins

in the skin or tissues that cover internal organs

Example: melanoma which is a type of skin cancer.

4 Basic Types of Cancer

Sarcoma Cancer that begins

in the bones, cartilage, fat, muscles, blood vessels, or other connective/supportive tissue

Example: osteosarcoma which is cancer in the bones

4 Basic Types of Cancer

Leukemia Cancer that starts in

blood-forming tissue such as the bone marrow and causes large numbers of abnormal blood cells to be produced and enter the blood.

Example – Acute Myeloid Leukemia is a cancer that begins in the white blood cells

Normal WBC

Leukemic WBC

4 Basic Types of Cancer

Lymphoma/Myeloma Cancer that begins

in cells associated with the immune system

Example: Non-Hodgkin's Lymphoma is a cancer that starts in the lymphocytes (cells of your immune system).

Some Causes of Cancer

Exposure to carcinogens Asbestos

lung cancer Formaldehyde

leukemia's, lymphomas, etc.

Exposure to UV rays Tanning Can cause skin cancer

Melanoma Basal cell carcinoma

Causes of Cancer

Smoking cigarettes Contain many carcinogenic chemicals Can cause a variety of cancer

Lung cancer (most common) Throat cancer Oral cancer

Other tobacco products Chewing tobacco

Oral cancer

Other Causes of Cancer

Heredity Breast cancer Kidney Cancer

Viruses HIV

Kaposi Sarcoma HPV

cervical cancer Hepatitis B

liver cancer

How do we detect cancer?

MRI Endoscopy X-ray Biopsy Ultra sound

Liver cancers Ovarian cancers

Mammogram Breast cancer For women 40 y/o

and older

How can we treat cancer?

Chemotherapy Drugs given to

target rapidly growing cells Not only kills cancer

cells but any rapidly growing cells like hair follicle cells

Surgery Remove the tumor

and surrounding tissue

Radiation treatment Applying

concentrated amount of energy to cancer cells to damage their DNA

Often times a combination of treatments can be used

Vaccines

Preventative To prevent the

emergence of cancer in healthy people

Examples HBV

Hepatitis B which can cause liver cancer

Gardasil Cervical cancer

Therapeutic/Treatment Used to treat

cancer