Genomics and MeGenomics and Me

The Study of Cancer DiseaseThe Study of Cancer Disease

IntroductionIntroduction

What is Cancer Disease?What is Cancer Disease? A set of disease in which cells escape from the A set of disease in which cells escape from the

control mechanismscontrol mechanisms Will cause deathWill cause death Cancer gene products produced in two waysCancer gene products produced in two ways QuantitativelyQuantitatively - gene products expressed at an abnormally - gene products expressed at an abnormally

level or not expressed at all.level or not expressed at all. QualitativelyQualitatively - DNA sequence changed (gene is mutated)- DNA sequence changed (gene is mutated)

How to detect the cancer gene?How to detect the cancer gene?

By comparing the “fingerprint” of a normal cell By comparing the “fingerprint” of a normal cell with a cancer cell will highlight genes by their with a cancer cell will highlight genes by their suspicious presence or absence, the cancer suspicious presence or absence, the cancer genome anatomist can determine whether such genome anatomist can determine whether such suspect play a role in cancer. suspect play a role in cancer.

Cancerous cell usually undergo a gradual Cancerous cell usually undergo a gradual transformation and often goes undetected for transformation and often goes undetected for years. Thus the cancer cell genetic study is very years. Thus the cancer cell genetic study is very important in cancer curing. important in cancer curing.

Causes of Cancer Causes of Cancer

ChemicalsChemicals - - Chemical in the workplace Chemical in the workplace e.g. manufacture of dyes and chemicals e.g. manufacture of dyes and chemicals - Tobacco and Alcohol - Tobacco and Alcohol - - Diet Diet aromatic amines and polycyclic hydrocarbonsaromatic amines and polycyclic hydrocarbons (over cooking)(over cooking) free radicals (metabolism of certain food)free radicals (metabolism of certain food) - Environmental pollution - Environmental pollution --aromatic hydrocarbons produced by the burning ofaromatic hydrocarbons produced by the burning of of wood, tobacco, and fossil fuels of wood, tobacco, and fossil fuels

VirusesViruses

e.g. e.g. hepatitis B virus (HBV) and the human hepatitis B virus (HBV) and the human immunodeficiency virus (HIV) immunodeficiency virus (HIV)

IrradiationIrradiation

Ultraviolet from sunlight and Ultraviolet from sunlight and atomic/ionizing radiation such as nuclear atomic/ionizing radiation such as nuclear explosions explosions

NNot all carcinogens do cause cancer because ot all carcinogens do cause cancer because most are eliminated by the immune system. most are eliminated by the immune system. one mutation usually is not enough to cause one mutation usually is not enough to cause

cancer cancer How cancer causes?How cancer causes? There is a cellular gene called There is a cellular gene called proto-proto-

oncogeneoncogene, which code for proteins that stimulate , which code for proteins that stimulate normal cell growth and division. When proto-normal cell growth and division. When proto-oncogene turns to oncogene turns to oncogeneoncogene , cancer will occur. , cancer will occur.

When proto-oncogene exposed to When proto-oncogene exposed to carcinogen (cancer-causers), its fragile sites will carcinogen (cancer-causers), its fragile sites will break and then proto-oncogene will turn tobreak and then proto-oncogene will turn to oncogene.oncogene.

The genetic changes that convert proto-The genetic changes that convert proto-oncogene to oncogene fall into three main oncogene to oncogene fall into three main categories categories

movement of DNA within the genome movement of DNA within the genome amplification of a proto-oncogene amplification of a proto-oncogene point mutation in a proto-oncogene point mutation in a proto-oncogene

Treatment Methods of CancerTreatment Methods of Cancer

Gene therapyGene therapya new technique of cancer treatment a new technique of cancer treatment to treat cancer patients by alter patient’s to treat cancer patients by alter patient’s

genetic material to fight or prevent cancer genetic material to fight or prevent cancer improve human body’s natural ability to improve human body’s natural ability to

fight the disease or make the cancer cells fight the disease or make the cancer cells more sensitive to other kinds of therapy more sensitive to other kinds of therapy

MethodsMethods supply cells with healthy copies of missing supply cells with healthy copies of missing

e.g. e.g. insert missing DNA into a certain genetic insert missing DNA into a certain genetic material by vectors material by vectors

altered gene by insert missing DNA or change altered gene by insert missing DNA or change cell’s function cell’s function

e.g. e.g. stimulate immune system cells to attack stimulate immune system cells to attack cancer cells, and to introduce the multidrug cancer cells, and to introduce the multidrug resistance (MDR) gene into stem cells resistance (MDR) gene into stem cells

the most common vectors are viruses. the most common vectors are viruses. RetrovirusesRetroviruses are usually used are usually used

ex vivo ex vivo

To To remove patients’ cells and grown the cells in remove patients’ cells and grown the cells in the laboratory . Exposed to cells to the virus that the laboratory . Exposed to cells to the virus that is carrying the desired gene. The virus will enter is carrying the desired gene. The virus will enter the cell, and the desired gene will become the the cell, and the desired gene will become the part of cells’ DNA. Finally inject the cells into part of cells’ DNA. Finally inject the cells into patients’ vein.patients’ vein.

in vivo in vivo

the desired gene is delivering to the patients’ the desired gene is delivering to the patients’ cells by vectors or liposomes inside the patients’ cells by vectors or liposomes inside the patients’ body. body.

The Side effectsThe Side effectswhen viral vectors carry desired gene into when viral vectors carry desired gene into

cells, they might altered genes of other cells, they might altered genes of other healthy cells healthy cells

the new gene might be inserted into the the new gene might be inserted into the wrong location in DNA wrong location in DNA

the transferred gene may be over the transferred gene may be over expressed that produce too much of expressed that produce too much of missing protein and may cause missing protein and may cause inflammation, and then the virus could be inflammation, and then the virus could be transmitted from the patients to other transmitted from the patients to other people people

The first disease approved for treatment The first disease approved for treatment with gene therapy was with gene therapy was adenosine adenosine deaminase (ADA) deficiencydeaminase (ADA) deficiency. .

The first clinical trial of gene therapy began The first clinical trial of gene therapy began in September 1990 in September 1990

SurgerySurgery Cryosurgery Cryosurgery

the use of extreme cold to destroy cancer the use of extreme cold to destroy cancer

side effects : can lead to heavy bleeding side effects : can lead to heavy bleeding Laser therapy Laser therapy

- - carbon dioxide (CO2) laser carbon dioxide (CO2) laser

- neodymium:yttrium-aluminum-garnet - neodymium:yttrium-aluminum-garnet (Nd: YAG) laser (Nd: YAG) laser

- argon laser - argon laser

ChemotherapyChemotherapy

The using of “antidrugs”.The using of “antidrugs”.

side effects : also harm to healthy cell side effects : also harm to healthy cell

Radiation therapyRadiation therapy

Also called radiotherapy, is the treatment of Also called radiotherapy, is the treatment of cancer with ionizing radiation. cancer with ionizing radiation.

usually used involves photons, such as X-ray usually used involves photons, such as X-ray And Gamma rays. And Gamma rays.

Side effects: Side effects: temporary or permanent loss of hair, temporary or permanent loss of hair, the skin irritation in the treated area.the skin irritation in the treated area.

Biological therapyBiological therapy

Sometimes called immunotherapy, is a Sometimes called immunotherapy, is a therapy that use the body immune system therapy that use the body immune system to fight cancer or to lessen the side effects to fight cancer or to lessen the side effects which caused by other cancer treatment.which caused by other cancer treatment.

It is to repair, stimulate, or enhance the It is to repair, stimulate, or enhance the immune system’s responses by using of immune system’s responses by using of antibodies, cytokines, and other immune antibodies, cytokines, and other immune substances. substances.

The EndThe End

Have a nice Christmas Have a nice Christmas