CANCER AND BIOTECHNOLOGY CHAPTER 19 and Chapter 21.
-
Upload
lorraine-harmon -
Category
Documents
-
view
217 -
download
0
Transcript of CANCER AND BIOTECHNOLOGY CHAPTER 19 and Chapter 21.
DNA
A MACROMOLECULE THAT CONTAINS THE INFORMATION NEEDED TO BUILD PROTEINS
AN ORGANISM’S STRUCTURE IS THE RESULT OF ALL THE DIFFERENT PROTEINS THAT ITS DIFFERENT CELLS MAKE
GENE
A SEGMENT OF DNA THAT CONTAINS THE RECIPE FOR A PROTEIN
A PROTEIN IS A POLYMER MADE OF AMINO ACIDS CONNECTED TOGETHER
CHROMOSOME
A LONG PIECE OF DNA CAN BE EXTENDED (CHROMATIN)
SO IT CAN BE READ CAN BE COMPACTED
(CHROMOSOME) SO IT CAN BE EASILY MOVED AROUND WHEN THE CELL DIVIDES
CHROMOSOMES
CHROMOSOMES ARE RECIPE BOOKS MADE UP OF THOUSANDS OF GENES (RECIPES FOR PROTEINS)
THE SUM OF ALL THE RECIPES IS THE ORGANISM
DNA STRUCTURE
A POLYMER COMPOSED OF UNITS CALLED NUCLEOTIDES
NUCLEOTIDE- PHOSPHATE, SUGAR, BASE
DNA BASES= A, T, C, G
DNA CONT.
DNA IS A DOUBLE STRANDED HELIX (SPIRAL)
THE 2 STRANDS ARE HELD TOGETHER BY HYDROGEN BONDS BETWEEN COMPLEMENTARY BASES
COMPLEMENTARY BASE PAIRING = A-T AND G-C
REPLICATION
COPYING THE DNA BEFORE CELL DIVISION
1. THE HELIX UNZIPS
2. DNA POLYMERASE INSERTS COMPLEMENTARY NUCLEOTIDES ACROSS FROM THE PARENT STRAND
WE HAVE 2 identical double stranded DNA MOLECULES
RNA
ALSO A POLYMER MADE UP OF NUCLEOTIDES
DIFFERENT SUGAR, SINGLE STRANDED
U INSTEAD OF T, A-U AND G-C COMPLEMENTARY RNA COPIES ARE
MADE BY RNA POLYMERASE
3 TYPES OF RNA
rRNA- WILL BECOME PART OF RIBOSOME
mRNA- A DISPOSABLE RNA COPY OF A GENE
tRNA- TRANSFERS THE CORRECT AMINO ACID TO THE RIBOSOME WHERE IT WILL BE CONNECTED IN THE CORRECT ORDER TO FORM A PROTEIN
MAKING A PROTEIN
2 STEPS
1. MAKE AN RNA COPY (mRNA) OF THE GENE FOR THE PROTEIN THE CELL NEEDS= TRANSCRIPTION
2. THE RNA COPY GOES TO THE RIBOSOME WHERE ITS INFORMATION IS USED TO CONNECT THE CORRECT AMINO ACIDS (AA’S) TOGETHER TO MAKE THE PROTEIN= TRANSLATION
DNA CODE
IT TAKES A SET OF 3 BASES (CODON) TO CODE FOR ONE Amino Acid (PROTEIN INGREDIENT)
TRANSCRIPTION- MAKES A COMPLEMENTARY RNA COPY OF A GENE- RNA POLYMERASE
TRANSCRIBE 30 BASES= ENOUGH INFO FOR 10 INGREDIENTS (10 AA’S)
TRANSLATION
THE mRNA MOVES TO THE RIBOSOME WHERE IT IS READ AND THE CORRECT PROTEIN IS MADE
THE RIBOSOME ACTS AS THE COUNTERTOP WHERE THE mRNA IS READ AND THE CORRECT INGREDIENTS (AA’S) ARE MIXED (CONNECTED) TOGETHER
tRNA’s are gophers
EACH DIFFERENT tRNA HAS A 3 BASE ANTI-CODON SEQUENCE ON ONE END
THE OTHER END CARRIES A SPECIFIC AMINO ACID
WHEN THIS SEQUENCE IS COMPLEMENTARY TO THE mRNA CODON- THAT tRNA WILL RUSH IN AND DROP OFF ITS AA
AA’S
AS THE CORRECT AMINO ACIDS ARE DROPPED OFF IN THE CORRECT ORDER BY THE tRNA’S (MATCHING THEIR ANTICODONS WITH THE mRNA CODONS) THEY ARE CONNECTED TOGETHER BY PEPTIDE BONDS TO FORM A POLYPEPTIDE= THE PROTEIN
BIOTECHNOLOGY
THE USE OF GENETIC ENGINEERING TO PRODUCE A DESIRED PRODUCT
GENETIC ENGINEERING= THE ALTERATION OF THE GENOME OF VIRUSES, BACTERIA AND OTHER CELLS
RESULTS
TODAY GENETICALLY ENGINEERED ORGANISMS MAKE INSULIN, GROWTH HORMONE AND MANY OTHER DRUGS WHICH TREAT CANCER AND CIRCULATORY DISORDERS.
PRODUCING A PROTEIN
1. CUT THE GENE THAT CODES FOR THE DESIRED PROTEIN OUT OF A HUMAN CELL
2. SPLICE THE GENE INTO A VECTOR WHICH TRANSFERS THE GENE TO THE HOST CELL
3. THE HOST CELL WILL TRANSCRIBE AND TRANSLATE THE GENE AND GIVE US THE PROTEIN
FORENSICS
A SEQUENCE OF DNA IS PRECISELY CUT OUT OF A HOST CELL WITH A RESTRICTION ENZYME. IT IS THEN COPIED HUNDREDS OF TIMES.
USE ANOTHER RESTRICTION ENZYME TO CHOP IT UP
GEL ELECTROPHORESIS- PROCESS THAT SEPARATES THE CHOPPED UP SEGMENTS BASED ON THEIR SIZES
FORENSICS
IDENTICLE DNA WILL FRAGMENT IN THE SAME LOCATION WHICH WILL PRODUCE THE SAME FRAGMENT PATTERNS ON A GEL
DNA FROM DIFFERENT PEOPLE WILL FRAGMENT AT DIFFERENT PLACES AND THE FRAGMENT PATTERNS WILL BE DIFFERENT
TRANSGENIC ORGANISMS
BACTERIA- MAKE CHEMICALS AND DRUGS (MAKE HUMAN INSULIN FOR DIABETICS)
PLANTS- RESIST INSECTS, DISEASES AND HERBICIDES, GROW BETTER
ANIMALS- BIGGER (PRODUCE GROWTH HORMONE), PRODUCE DRUGS IN THEIR MILK.
DNA PROBES
SMALL RADIOACTIVE SINGLE STRANDED DNA SEQUENCES MIXED WITH CHROMOSOME
CAN IDENTIFY THE LOCATION OF GENES ON A CHROMOSOME BY HYBRIDIZING (MATCHING) WITH THEM
USED TO IDENTIFY GENETIC DISEASES
CAUSES
CARCINOGEN- THREE TYPES
RADIATION- X-RAYS, ULTRAVIOLET= UV (SUN), RADON
ORGANIC CHEMICALS- TOBACCO, HIGH FAT DIET, POLLUTANTS, DYES
VIRUSES- HEPATITIS B- LIVER CANCER, GENITAL WARTS- CERVICAL CANCER
HEREDITY
CERTAIN TYPES CAN BE INHERITED AS MUTATIONS
BREAST, LUNG AND COLON- IF A FIRST DEGREE RELATIVE HAS IT THEN YOUR RISK INCREASES 2-3x
SOME LESSER KNOWN CANCERS CAN BE INHERITED AS A DOMINANT ALLELE
IMMUNODEFICIENCIES
OUR IMMUNE SYSTEM SOMETIMES RECOGNIZES CANCER CELLS AS “BAD” AND ATTACKS THEM.
IF THE IMMUNE SYSTEM IS WEAK (AIDS OR IMMUNOSUPPRESSIVE DRUGS) THE BODY IS LESS LIKELY TO ATTACK CERTAIN CANCERS.
CARCINOGENESIS
THE DEVELOPMENT OF CANCER
1. INITIATION- A MUTATION
2. PROMOTION- CELLS DIVIDE QUICKLY
3. PROGRESSION- CANCER CELLS INVADE BLOOD OR LYMPH VESSELS AND SPREAD TO OTHER PARTS OF THE BODY
CANCER CELLS UNDER THE MICROSCOPE
NO DIFFERENTIATION- DISORGANIZED LAYERING, GENERIC ROUND CELLS
ABNORMAL NUCLEI- ENLARGED NUCLEUS, EXTRA OR MISSING CHROMOSOMES
FORM TUMORS- CELLS KEEP DIVIDING, A MASS OF CELLS IS PRODUCED
TUMORS
BENIGN- TUMOR DOES NOT SPREAD, ENCAPSULATED
MALIGNANT- TUMOR SHOWS SIGNS OF SPREADING, HAS ITS OWN BLOOD SUPPLY
ANGIOGENESIS
THE FORMATION OF NEW BLOOD VESSELS TO SUPPLY A TUMOR WITH OXYGEN AND NUTRIENTS
CANCER CELLS RELEASE A GROWTH FACTOR WHICH PROMOTES THE GROWTH OF NEW BLOOD VESSELS
METASTASIS
NEW TUMORS GROW IN LOCATIONS AWAY FROM THE PRIMARY TUMOR
CANCER CELLS MUST PRODUCE A PROTEINASE ENZYME THAT EATS THROUGH SURROUNDING TISSUE.
WHEN A BLOOD OR LYMPH VESSEL IS REACHED, CANCER CELLS ARE CARRIED ELSEWHERE WITH THE FLOW OF THESE FLUIDS
PROGNOSIS= LIKELY OUTCOME
DEPENDS ON:
1. IF THE PRIMARY TUMOR HAS INVADED SURROUNDING TISSUE
2. IF LYMPH NODES WERE INVADED
3. IF THERE ARE TUMORS IN OTHER PARTS OF THE BODY
GENETIC BASIS
PROTO-ONCOGENES- NORMAL GENES WHICH CODE FOR PROTEINS WHICH REGULATE CELL DIVISION
A MUTATION CAN CHANGE THESE GENES INTO ONCOGENES.
ONCOGENES- CAUSE CELL TO DIVIDE REPEATEDLY
OTHER GENES
TUMOR SUPPRESSOR GENES- CODE FOR REGULATORY PROTEINS THAT ACT TO SLOW DOWN OR PREVENT UNNECESSARY CELL DIVISION LIKE A BRAKE
IF THESE “BRAKES” ARE DAMAGED, THEN CELL DIVISION MAY GET OUT OF CONTROL
DIAGNOSIS
SCREENING TESTS CERVICAL- PAP SMEAR- LOOKED AT
UNDER MICROSCOPE BREAST- SELF EXAM, MAMMOGRAM COLON- DIGITAL EXAM (FINGERS
FEEL FOR RECTAL CANCER), SIGMOIDOSCOPY, STOOL BLOOD TEST, BARIUM ENEMA / X-RAY.
TUMOR MARKER TESTS
CANCER CELLS SOMETIMES PRODUCE FOREIGN CHEMICALS THAT SHOW UP IN BLOOD TESTS
MEASURING THESE CHEMICALS CAN INDICATE THE PRESENCE OR PROGRESSION OF CANCER (PROSTATE CELLS MAKE PSA- OLDER MEN SHOULD GET A PSA TEST)
HIGH PSA IN BLOOD MEANS OVERACTIVE PROSTATE CELLS- COULD BE CANCER
GENETIC TESTS
LOOK AT DNA SEQUENCES OF SPECIFIC GENES, USEFUL FOR DETERMINING CANCER RISKS LONG BEFORE A TUMOR DEVELOPS
OTHER TESTS
NEEDLE BIOPSIES DIRECTLY SAMPLES LUMP AND THEN SENT FOR MICROSCOPIC EXAMINATION
CAT AND MRI SCANS ULTRASOUND
TREATMENT
SURGERY- REMOVES CANCEROUS CELLS
RADIATION- KILLS CANCEROUS CELLS (AS WELL AS SOME NORMAL CELLS)
CHEMOTHERAPY- DRUGS THAT KILL CANCER CELLS BY DAMAGING DNA OR INTERFERING WITH WITH DNA SYNTHESIS
CHEMOTHERAPY
SPECIFIC DRUGS ARE USED ON SPECIFIC CANCERS
DIFFERENT COMBINATIONS OF DRUGS CAN BE USED TO AVOID RESISTANCE PROBLEMS
ANTIHORMONE THERAPY
BLOCKS HORMONES THAT CAN CAUSE CANCER
ESTROGEN- CAN LEAD TO CANCER OF BREAST
TESTOSTERONE- CAN LEAD TO CANCER OF PROSTATE
BONE MARROW TRANSPLANT
SOMETIMES USED TO TREAT BLOOD CANCERS (Leukemia) BECAUSE BLOOD CELLS ARE MADE BY BONE MARROW
1. REMOVE BONE MARROW AND THEN KILL THE CANCEROUS CELLS IN IT
2. MASSIVE CHEMO AND RADIATION TO KILL ALL CANCER CELLS IN THE BODY
3. REPLACE BONE MARROW
FUTURE TREATMENTS
IMMUNOTHERAPY- BREED TUMOR KILLING WHITE BLOOD CELLS OR HOOK CHEMOTHERAPY DRUGS TO ANTIBODIES WHICH WILL ATTACH TO TUMOR CELLS
ANTI ANGIOGENESIS- DRUGS THAT CUT OFF BLOOD SUPPLY TO TUMOR
ANTI METASTATIC- STOP ENZYME THAT ENABLES SPREAD
GENE THERAPY- REPLACE ONCOGENES WITH PROTO ONCOGENES