Cancer unit

Interphase

Where cell spends majority of time. Cell performs all of its normal functions.

Telomeres

"cellular fuse" at the end of each chromosome that shorten each time they pass thru the cell cycle until they reach apoptosis (when a chromosomes telomere has been shortened too much to go thru the cell cycle again).

The role of chromosomes

"filing cabinets" for DNA. Each chromosome has hundreds of thousands of genes on it that contain instructions for running the cell. We have two complete sets of 23 chromosomes.

Mammogram

(most common form of screening) uses x-rays to examine breast tissue for cancer -screening mammogram: recommended for women over 40, to look for any abnormalities in the breast that may potentially be associated with cancer. -diagnostic mammogram: more detailed look at a specific area of the breast, usually b/c of a specific lump in the breast or a blood test that detected blood markers associated with cancer.

Alkaloids and Taxanes (class of chemo)

-Alkaloids are naturally produced chemicals that interfere with the ability of the cell to form spindle fibers that separate the sister chromatids during mitosis. (inhibit the formation of microtubules, one of the proteins in the spindle fiber) -Taxanes are naturally produced by the yew tree. They prevent the breakdown of microtubules, this keeping the sister chromatids attached to the spindle fibers preventing cell division

creating a cancer vaccine

1.) white bloods cells are removed from the body then stimulated to divide. 2.) they are exposed to an antigen (normally found on the surface of cancer cell) 3.) the W.B.C's uptake some of the antigen and are returned to the body. 4.) the cells then act as a messenger to the cells of the immune system responsible for destroying foreign invaders (cytoxic T cells) 5.) the cytoxic T cells then seek out cancer cells and destroy.

Cancer

A disease that is caused by an inability of the body to control cell division. This excess of cells may form tumors or increase the number of cells in the blood. As cancer cells increase, they cause physiological changes that frequently interfere with the operation of a tissue or organ.

Biopsy

A surgical procedure to remove a small section of tissue to look for the presence of cancer cells.

quaternary structure of a protein

At times, protein chains (polypeptides) interact with one another, forming large molecules that have more complex functions.

Stage 0

Cancer cells located in very small area. Detected early

G2 phase

Growth occurs as cell prepares to divide.

M checkpoint

Mitosis stops until chromosomes are properly aligned

Gene Expression

Series of steps by which a cell uses the information within specific regions of the DNA (genes) to form a functional protein. (Go over obstacles)

Genome

Sum of all the genetic information in a cell.

prophase

The genetic material condenses into compact chromosomes, and SPINDLE FIBERS form from the centrioles to help align chromosomes.

Mitosis

The genetic material is equally divided into two new nuclei. Consists of prophase, metaphase, anaphase, and telophase.

Cell

The smallest unit of biological organization that has all the characteristics of life. Function by acquiring materials to manufacture both cellular components (organelles) and materials for export into the body (hormones or chemical signals).

Chemotherapy

The us of a drug to treat a disease. Targets the characteristics of fast growing cells. Affects ALL of the cells in the body. Can interfere w/ any type of rapidly dividing cells, such as cells lining or digestive system and blood cells.

M phase

When cell division occurs. Consists of 2 parts: 1.)Mitosis 2.)cytokinesis

Cells operate as BIOLOGICAL FACTORIES, each with specific purpose in the body

cells are organized into tissues (connective, muscle, etc..) and then into organs (such as heart) and finally into organ systems (such as the cardiovascular system)

Proteinase

enzyme released from malignant tumors that digest protein molecules and allows the cells of the tumor to move into surrounding tissue.

Telomerase

enzyme that prevents telomeres from shortening making them immortal.

Biochemical Pathway

enzymes linked together in an assembly-line fashion to produce a product

Proto-oncogenes

genes that accelerate the cell cycle/promote growth and development. Activated by growth hormones. Becomes a ONCOGENE when a mutation causes it to be in an active state w/out influence of a growth hormone, or causes it to be more sensitive to growth hormones.

immunotherapy

involves the use of the body's immune system to identify and eliminate cancer cells. Generally the immune system is the body's defense against infectious organisms/ invaders but cancer cells can escape the attention of the immune system. Immunotherapy is designed to convince the immune system to identify the cancer cells as foreign.

primary structure of a protein

linear sequence of amino acids, as directed by the sequence of codons in the DNA.

Blood marker tests

look for proteins that are being produced by cancer cells or tumors. most cancer will produce proteins that are not normally found in the blood.

complete blood count (CBC)

looks for the presence of normal blood cells in their correct amounts. Some cancers may elevate the white blood cells in the body. If metastasis has occurred it may also be possible to detect the presence of tumor cells in the blood.

Benign tumor

often closely resembles surrounding tissue. Localized to one tissue type and has not invaded surrounding tissue.

Cell cycle

series of events that cells go through as they grow and divide

polymerase chain reaction (PCR)

technique that allows molecular biologists to make many copies of a particular gene. -DNA polymerase: molecule that makes the copies of the target gene. Derived from thermostable bacteria (aka taq polymerase) -primers: target the gene of interest. DNA SEQUENCING then determines the exact sequence of the nucleotides in the target gene. After the sequencing, the patterns of nucleotides are compared to a normal gene.

tertiary structure of a protein

the protein begins to from a 3-D molecule, in many cases capable of performing its function as an enzyme (globular shape)

amaphase

the sister chromatids separate and migrate to opposite sides of the cell.

P53 gene (aka TP53)

A tumor suppressor gene that produces a protein that is responsible for activating DNA repair enzymes and stopping the cell cycle and placing the cell in the G0 phase. Promotes the process of apoptosis if DNA cannot be repaired. Mutations are correlated with breast cancer.

metastasis

when cells from a tumor enter into the lymphatic vessels or capillaries of the circulatory system. (spread thruout the body)

angiogenesis

when tumors release specialized growth factors that cause the local capillaries of the circulatory system to grow toward the tumor.

External radiation (most common)

-Patient is placed in specific position -often accompanied by a CT scan so the technician knows exactly where to target the beam of energy -Most use x-rays, but sometimes need higher energy gamma rays -often multiple rounds of external radiation are performed over a couple of weeks.

Questions to determine the stage of cancer

-how large is the tumor? -has the tumor begun to invade nearby tissue? -is the cancer location in the nearby lymph nodes? -has the cancer moved to any other organs in the body?

cytokinesis

2nd part of the M phase. Divides the organelles and cytoplasm into two new daughter cells. The plasma membrane is pinched inward until the daughter cells form around the two new nuclei. Often begins before the end of telophase.

4 Nitrogen bases

Adenine (2 rings)-->Thymine (1 ring) Cytosine (1 ring)-->Guanine (2 rings)

G1 phase

Cell growth occurs as organelles double.

Mutation

Change to the nucleotide sequence of a DNA molecule.

Stage 2

Considered to be invasive. The tumor has grown is size but is still located entirely in the breast. -Stage 2A: Either smaller than 2cm (or cannot be detected) and cancer cells have been detected in multiple lymph nodes, or the tumor is 2-5 cm but has not spread to lymph nodes. -Stage 2B: Size has increased to 2-5 cm and cancer cells have been detected in nearby lymph nodes.

S phase

DNA replication occurs in the nucleus of the cell where each homologous chromosome is copied, forming identical sister chromatid. Until the M phase, the sister chromatids are held together in the CENTROMERE. Between G1 and G2 phases.

magnetic resonance imaging (MRI)

DOES NOT use radiation. Uses radio waves and magnets to generate detailed pictures of the body. Used for screening of high-risk patients and to diagnose the extent and spread of the cancer in the body.

Pathologist

Doctors who diagnose disease based on lab results. Use T.N.M classification: -T=The size of the tumor. "Tx" indicates tumor can't be found "T1-4" represents size. -N= The number of lymph nodes where cancer is detected. -M: Whether the cancer has metastasized to other organs of the body. M0 or M1.

Difference between a normal cell and a cancer cell

In a cancer cell, some changes have been made to the DNA so the proteins and enzymes of the cell no longer function correctly potentially causing the cell to divide more rapidly.

Transcription

Information in the gene of interest is copied into an mRNA molecule. 1.) An enzyme called RNA Polymerase identifies the gene and unwinds the double helix, exposing the nucleotide bases on the interior of the DNA. 2.) The RNA Polymerase uses one of the DNA strands (the template strand) to produce a complementary RNA copy, called mRNA. Instead of thymine, the mRNA uses uracil (U). 3.) The RNA Polymerase releases, and the DNA re-forms a double helix.

G2 checkpoint

Mitosis will not occur until DNA has replicated

Stage 3

More invasive. Beginning to affect more of the tissue of the breast and surrounding tissues. Has not yet spread to distant organs. -Stage 3A: Either <2cm, but has spread to more than 4 lymph nodes, or is larger than 5 cm, but has not spread to lymph nodes. -Stage 3B: (Regardless of size) has spread to either the wall of the breast/skin on breast and has infected more than 9 lymph nodes. Includes swelling, inflammation, ulcers on the breast. -Stage 3C: (Regardless of size) has spread either to the area of the collarbone or >10cm lymph nodes.

BRCA1 gene

Produces a protein that is active at the G1 checkpoint. Inspects DNA for breaks in strands. If breaks are detected, cell is sent to G0 phase for repair or apoptosis. Mutations are responsible for many different types of cancer.

Computerized Tomography (CT) scan

Special type of x-ray procedure that takes pictures of the organs from different angles. Involves an injection of a contrast dye in the circulatory system. Useful in detecting whether the cancer is spreading to other organs or if a treatment is being effective.

Stage 4

The cancer has fully metastasized and has spread to organs outside of the breast. In breast cancer, this typically includes the lungs, heart, brain, and liver. Often labeled incurable.

Translation

The mRNA moves from the nucleus to one of the ribosomes to translate into protein. A CODON is a three-base sequence that helps specify which amino acid should be used in the process of forming a protein. 1.) The mRNA molecule arrives at the ribosome for translation. 2.) The mRNA molecule is read one codon at a time. This is done by the tRNA molecule that is complementary to the base sequence of the mRNA codon. Certain codon combinations correspond to 1 of the 20 amino acids that may be used to build the protein. 3.) As the codons on the mRNA molecule are read, each corresponding amino acid is added to the growing protein chain. 4.) Once the info in the mRNA is processed, the ribosome and mRNA separate and may be used again to produce another protein molecule. 5.) Once the info in the mRNA is processed, the ribosome and mRNA separate and can be used again to produce another protein molecule.

Genome editing

The targeting of specific sequences in a DNA molecule for editing. Most common = CRISPR....uses an enzyme called CAS9 that identifies the specific sequence of DNA to be edited via an RNA molecule that complementary base pairs to the DNA sequence. PAM (regulatory region) helps make sure the CAS9 enzyme has the correct DNA sequence. CRISPR may be used to either remove nucleotides, thus inactivating the gene, or inserting nucleotides, thus changing the function of the gene.

Stage 1

Tumor has begun to invade surrounding tissue. -Stage 1A: Tumor is small (<2cm) but has not spread to any nearby lymph node. -Stage 1B: The tumor is <2cm or cannot be detected, but small groups of cancer cells are found in a few surrounding lymph nodes.

ERBB2

Type of oncogene associated w/ breast cancer. Produces a protein called HER-2 which is found on the surface of epithelial cells, such as those in breast tissue. Amplification or mutation causes cells to divide more frequently.

Antimetabolites

Typically mimic the nucleotides used in the building of a DNA molecule. Similar structure to a nucleotide so they can be integrated in but different enough to interfere with the DNA replication machinery during the S phase of the cell cycle. Some are called "antibiotics" (different from normal) These antibiotics either prevent the enzymes involved in DNA replication from functioning or interfere w/ the ability of the DNA to form RNA during gene expression.

Genetic testing

Uses a simple blood test to detect the presence of specific mutations in known cancer genes (such as BRCA1). After blood test, DNA is isolated from white blood cells and subjected to a process called polymerase chain reaction to make multiple copies of the gene.

Gene

Within the genome. Provide instructions for forming a specific protein (or enzyme).

Carcinoma

a cancer arising in the epithelial tissue of the skin or of the lining of the internal organs

Apoptosis

a powerful way that the body has of removing cells that have excessive damage or may no longer be needed by the body.

lymph nodes

a small bean shaped structure that is part of the immune system. Filter substances that travel thru the lymphatic fluid. Contain lymphocytes (white blood cells) that help the body fight infection/disease.

antigen

a toxin or other foreign substance that induces an immune response in the body, especially the production of antibodies.

function of DNA

allows it to function as an information-storage system. Made up of units called nucleotides. Each nucleotide consists of: 1.) a 5-carbon sugar called deoxyribose 2.) a phosphate group 3.) a nitrogen-containing base When these nucleotides are linked together, they form a single strand of DNA.

Mutagen

an agent that is known to cause mutations in DNA. If a mutagen is known to be directly associated with a specific form of cancer it is called a CARCINOGEN.

telophase

at the end, the new nuclei (2 daughter cells) has the same number and type of chromosomes as the mother cell.

DNA

belongs to a class of organic molecules called the nucleic acids. In a cell, the nucleic acids are responsible for storing and processing genetic information. This info allows the cell to produce proteins and enzymes that enable most cellular functions.

Leukemia

blood cancer (white blood cells produce rapidly)

Lymphoma

cancer originating in cells and tissues of immune system

Sarcoma

cancer originating in connective tissue such as a bone

malignant tumor

cells do not resemble other cells of the other tissue and are very unspecialized. Have the ability to invade other tissues and potentially move to other parts of the body.

G1 checkpoint

checks to see if there is any damage to the DNA. If there is, the cell enters the G0 phase. In the G0 phase, the cell will attempt to repair the damage to the DNA. If that is not possible, then the cell may be targeted for cell death using a process called apoptosis.

Alkylating agents (class of chemo)

chemicals that integrate into the DNA, typically causing the DNA to break at specific points. Can potentially lead to mutations (leukemia)

metaphase

each of the homologous chromosomes aligns along a central line in the cell. This will allow one of the sister chromatids to move toward each of the new cells ensuring that the new cells have the same genetic information.

Positron Emmission Tomography (PET) scan

examines how the cells of the body are functioning by providing them with sugar that contains a small amount of radioactive tracer. Cells that are more active (cancer cells), will take up more of the sugar. Useful in determining if cancer has moved to nearby lymph nodes or tissues.

systematic radiation

form of internal radiation. 1.) use of specific radioactive elements relative to their normal location. 2.) use of targeting molecules. May use antibodies designed to target specific cells of the body (monoclonal antibodies) can be manufactured in the lab to target specific proteins on the surface of the cancer cells.

How the DNA molecule stores genetic information

in the sequence of the bases on the interior of the double helix.

Topoidomerase inhibitors

interfere with the ability of the cell to replicated its DNA. disable a key enzyme of gene replication called topoisomerase. Topoisomerase helps unwinding the DNA.

Tumor-Supressor Genes

responsible for preventing unregulated cell growth.

DNA microarray

silicon chips or microscope slides with DNA fragments that can allow many genes in a genome to be studied simultaneously

Melanoma

skin cancer

secondary structure of a protein

the amino acids begin to interact with one another based on weak chemical reactions (helix or sheet shaped).

Radiation

the movement of energy in the form of either waves or particles. In radiation therapy, physicians typically use x-rays and gamma rays (b/c they contain the most energy to direct against specific cells). Radiation may also be in the form of particles such as alpha and beta particles. Radiation works by damaging the DNA within a cell, with the intent of causing it to slow or stop cell division. unlike chemotherapy, radiation can be directed against specific tissues and cells of the body. Not as effected in destroying cancer cells that have metastasized. Sometime combined with chemo.

internal radiation (aka brachytherapy)

uses small deposits of radioactive materials that are placed inside the body in the form of pellets (called seeds). The radioactive material emits radiation which damages the DNA of surrounding cancer (and healthy) cells. 1.) interstitial brachytherapy: seeds are placed in direct contact with tumor 2.)intracavitary brachytherapy: seeds are placed i nearby body cavity.