CancerCancereverything you’ve wanted to everything you’ve wanted to

knowknow

Alex J CrandonAlex J CrandonMBBS (Syd) PhD (Leeds) FRCOG (Lond) FRANZCOG (Melb) MBBS (Syd) PhD (Leeds) FRCOG (Lond) FRANZCOG (Melb)

CGOCGO

Gynaecological OncologistGynaecological OncologistMater and Brisbane PrivateMater and Brisbane Private

Cancer – What is it?Cancer – What is it?

Cancer is a group of diseases Cancer is a group of diseases characterized by uncontrolled characterized by uncontrolled growth and spread of abnormal growth and spread of abnormal cells. cells.

If the spread is not controlled, it If the spread is not controlled, it can result in death.can result in death.

Cancer – Will we find a Cancer – Will we find a cure?cure?

Simply – No!Simply – No!

Why wont we find a Why wont we find a cure?cure?

Cancer is a Cancer is a group of diseasesgroup of diseases characterized by uncontrolled growth characterized by uncontrolled growth and spread of abnormal cells.and spread of abnormal cells.

Cancer is 100’s of different diseasesCancer is 100’s of different diseases That’s why we wont find That’s why we wont find a curea cure. .

Cell numbersCell numbers

From birth to sexual maturity the From birth to sexual maturity the number of cells is continually number of cells is continually increasing.increasing.

We die with approximately the We die with approximately the same number of cells that we same number of cells that we had at sexual maturity.had at sexual maturity.

Cellular control Cellular control mechanismsmechanisms

Cellular ReproductionCellular Reproduction

Cancer is a genetic Cancer is a genetic diseasedisease

Chromosomes Chromosomes control cells.control cells.

Chromosomes Chromosomes are made up of are made up of DNA.DNA.

If the DNA is If the DNA is damaged damaged (mutation) then (mutation) then the cell behaves the cell behaves abnormally.abnormally.

Looking at DNALooking at DNA

DNA is a very DNA is a very complex complex molecule.molecule.

The sequence of The sequence of chemical chemical combinations combinations provide the code provide the code for the DNA.for the DNA.

DNA – looking closelyDNA – looking closely

Cytosine can Cytosine can only combine only combine with Guaninewith Guanine

Tyrosine can Tyrosine can only combine only combine with Adenosinewith Adenosine

DNA damageDNA damage

Damage may be Damage may be caused by UV light caused by UV light some chemicals & some chemicals & radiationradiation

The damage alters The damage alters the base so it the base so it looks like another looks like another basebase

Mutation formation 1Mutation formation 1

When the DNA When the DNA strands are strands are separated & separated & copied the altered copied the altered base will pair with base will pair with an incorrect base.an incorrect base.

The altered The altered guanine has guanine has paired with a paired with a tyrosinetyrosine

Mutation formation 2Mutation formation 2

Nuclear radiation Nuclear radiation can break DNAcan break DNA

Cells try to fix Cells try to fix the breaks by the breaks by joining the free joining the free ends to other ends to other pieces of DNA pieces of DNA (translocation).(translocation).

Mutation formation 3aMutation formation 3a

When cells When cells reproduce they reproduce they have to make have to make two identical two identical copies of their copies of their entire DNA.entire DNA.

The two DNA The two DNA strands must strands must first be first be separated by separated by DNA helicase.DNA helicase.

Mutation formation 3bMutation formation 3b

DNA polymerase DNA polymerase copies each copies each strand to create strand to create two double two double strands of DNAstrands of DNA

DNA polymerase DNA polymerase makes a mistake makes a mistake ~ 1 in ~ 1 in 100,000,000 100,000,000 basesbases

DNA repair mechanismsDNA repair mechanisms

Repair proteins Repair proteins mark the mark the abnormal DNA.abnormal DNA.

The abnormal The abnormal fragment is fragment is removed.removed.

DNA polymerase DNA polymerase repairs the repairs the missing bit missing bit copying from the copying from the opposite strand.opposite strand.

Cancer is a disease of Cancer is a disease of ageage

As we age the As we age the chances of these chances of these complex systems complex systems going wrong going wrong increases.increases.

Cancer is largely Cancer is largely a disease of age a disease of age – its incidence – its incidence increases with increases with ageage