cancer therapies

8/8/2019 Cancer Therapies

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Cancer is a class of diseases inwhich a group of cells displayuncontrolled growth ( division beyondthe normal limits), invasion (intrusionon and destruction of adjacent

tissues), and sometimes metastasis(spread to other locations in the bodyvia lymph or blood). These threemalignant properties of cancersdifferentiate them from benign tumors ,which are self-limited, do not invadeor metastasize. Most cancers form atumor but some, like leukemia , do not.The branch of medicine concernedwith the study, diagnosis, treatment,and prevention of cancer is oncology .



GENE THERAPYGENE THERAPY

RADIOTHERAPYRADIOTHERAPY

C AN CER VA CCINESC AN CER VA CCINES

IMMUNOTHERAPYIMMUNOTHERAPY

C AN CERC AN CER VA CCINES

ANTI ANTI- -ANGIONESIS ANGIONESIS

HORMONEHORMONE THERAPYTHERAPY

CHEMOTHERAPYCHEMOTHERAPY

MONO CLONA LMONO CLONA L ANTIBODIES

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Gene Therapy



What is gene therapy and how does it work?



In the center of every cell in your body is a regioncalled the nucleus. The nucleus contains your DNA (deoxyribose nucleic acid), which is the genetic code you inherited from each of your parents. The DNA isribbon-like in structure, but normally exists in acondensed form called chromosomes.

You have 46 chromosomes, which are in turncomprised of thousands of genes. These genes carry specific instructions that tell cells how to work,control our growth and development, and determine

what we look like and how our bodies work.They alsoplay a role in the repair of damaged cells and tissues.Each person has more than 30,000 genes, which aremade up of DNA . You have 2 copies of every gene, 1inherited from your mother and 1 from your father.



y

FIGHTING CA N CER W ITH G EN ES1 B lood taken from patient

2 T cells infected with virus to carry key genes into them

3 DNA from genes helps cellsdevelop receptor

4 Modified cells injected back into

patient5 Receptors target cancerous cells to

be killed



R adiotherapy



Radiotherapy is the use of radiation to treat cancer.The radiotherapy is targeted at the part of yourbody where the cancer has been found. The aim of the treatment is to destroy the cancer cells in the

area being treated. Normal cells will also beaffected but they are better able to repairthemselves. Preparation for radiotherapy can takelonger than the treatment. To find the exact

position of the cancer, your doctor will use X-ray scans and CT (computerised tomography) scans, which give a three-dimensional picture of yourinternal organs.



THER E AR E TWO MAIN TYPE OF R ADIOTHER APY

1: External radiotherapy

2: Internal radiotherapy



External radiotherapy External radiotherapy is where a machine is used togive a dose of energy, such as X-rays, to attack thecancer cells. There are different types of radiotherapy

machines, which work in slightly different ways. Fora session of radiotherapy you will be asked to sit orlie in a position that allows the energy beam to bedirected accurately at the cancer. The machine looks

like an X-ray machine. It won't touch you and you won't feel any pain during the treatment. Thenumber and duration of the radiotherapy sessionsdepends on the type of cancer and where it's located

in your body.



Internal radiotherapy

I nternal radiotherapy is where the source of I nternal radiotherapy is where the source of radioactivity is put inside your body so it can get radioactivity is put inside your body so it can get

closer to the cancer.closer to the cancer.

This can be done in two ways:This can be done in two ways:

1: B rachytherapy1: B rachytherapy2 : 2 : R adioisotope therapyR adioisotope therapy



B rachytherapy This is when a solid source of radioactivity is put next to a tumour to give a high dose of radiotherapy.This means the effect on body tissue around the cancer isas little as possible. B rachytherapy can be used to treat

cancers of the cervix, head and neck, womb(uterus), prostate gland and skin . You will need tohave a minor operation to put the radioactive source into your body and you will usually need to stay in hospital for afew days while it's in place. Once the treatment is over, adoctor or nurse will remove the radioactive source and you will be able to go home.



Radioisotope therapy

This is when a liquid radioactive source isput inside your body. A radioactive liquid(usually radioactive iodine) is giveneither as an injection into a vein or as aliquid you can drink. Radioisotopetreatment can be used for thyroid,adrenal and bone cancers.



CANCER VACC INES



Cancer vaccines are designed to teach the immunesystem to attack and destroy cancer cells. Normally, when foreign cells enter the body (for example, whenan infection occurs), the immune system responds tothe invasion and clears the body of the foreign cells.Unlike infectious cells, cancer cells are notrecognized as foreign by the body. Instead, theimmune system thinks the cancer cells are part of thenormal body and do not mount an immune response

against the cancer. Cancer vaccines allow theimmune system to recognize cancer cells as foreignand, therefore, get the immune system to attack thecancer cells.



Drugs that block cancer bloodvessel growth (anti-angiogenics)



An angiogenesis inhibitor is a substance that inhibits

angiogenesis (the growth of new blood vessels). It can beendogenous or come from outside as drug or a dietary component . Every solid tumor (in contrast to liquid tumorslike leukemia ) needs to generate blood vessels to keep it aliveonce it reaches a certain size. Usually, blood vessels are notbuilt elsewhere in an adult body unless tissue repair is actively in process.

The angiostatic agent endostatin and related chemicals cansuppress the building of blood vessels, preventing the cancerfrom growing indefinitely. In tests with patients, the tumorbecame inactive and stayed that way even after the endostatintreatment was finished. The treatment has very few sideeffects but appears to have very limited selectivity. Otherangiostatic agents like thalidomide and natural plant-basedsubstances are being actively investigated.



IMMUNOTHE R APY



Cancer immunotherapy is the use of the immune system toreject cancer . The main premise is stimulating the patient'simmune system to attack the malignant tumor cells that areresponsible for the disease. This can be either throughimmunization of the patient, in which case the patient's ownimmune system is trained to recognize tumor cells as targetsto be destroyed, or through the administration of therapeuticantibodies as drugs, in which case the patient's immunesystem is recruited to destroy tumor cells by the therapeuticantibodies.Since the immune system responds to the environmentalfactors it encounters on the basis of discrimination between

self and non-self, many kinds of tumor cells that arise as aresult of the onset of cancer are more or less tolerated by thepatient's own immune system since the tumor cells areessentially the patient's own cells that are growing, dividingand spreading without proper regulatory control.



H ormone Therapyy What hormones arey

H

ormones are natural substances made by glands in ourbodies. The network of glands that make hormones iscalled the endocrine system. H ormones are carried in ourbloodstream and act as messengers between one partof our body and another. They control the growth and

activity of certain cells and organs



y What hormone therapy isH ormone treatments use the sex hormones produced by ourbodies, or drugs that block them, to treat cancer. Not allcancers respond to hormone therapy. Doctors might usehormone therapy for people with cancers that are hormonesensitive or hormone dependent . This means that thecancer needs the hormone to grow.

y Cancers that are hormone sensitive or hormone dependentneed hormones to grow. So stopping the hormone reachingthe cancer cells may either slow down or stop the growth of the cancer. H ormone therapies can work by either

y Stopping hormones being madey Preventing the hormone reaching the cancer cell



Chemotherapy



y What chemotherapy isy It literally means 'drug treatment'. In cancer

treatment, the term chemotherapy meanstreatment with cell killing (cytotoxic) drugs. Youmay have just one chemotherapy drug or acombination of different chemotherapy drugs. There are more than 70 different drugscurrently available and new ones are beingdeveloped all the time.



How chemotherapy worksy You have chemotherapy given into the bloodstream or you

have it as tablets or capsules. The drugs circulate all roundthe body in the bloodstream and damage cells that aredividing. B ody tissues are made of billions of individual

cells. Once we are fully grown, most of the body's cells don'tdivide much. They spend most of their time in a resting stateand only divide if they need to repair damage. When cellsdivide they split into two, identical new cells.

Cells in the process of dividing are more at risk of beingdamaged by chemotherapy. And cancer cells divide much,much more often than most normal cells.



TR EATMENT OF CANCER BY MONOCL ONAL ANTIBODIES

y H ow monoclonalantibodies workMonoclonal antibodiesare designed to recogniseand find specificabnormal proteins on theoutside of cancercells. Each monoclonalantibody recognises oneparticularprotein. Different typesof cancer have differentabnormal proteins. Sodifferent antibodies haveto be made to targetdifferent types of cancer.



y Several different monoclonal antibodies are

already available to treat cancer. Some arelicensed to treat particular cancers and someare still in clinical trials.



REFRENCESy 1. www.cancer.orgy 2. www.sciam.comy 3. www.wikipedia.com



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cancer therapies

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