D NA R E PA I R

Maria Angélica Zapata GonzálezMedicine Student

M E D I CA L U T I L I T Y

By: Maria Angélica Zapata Gonzalez

Molecular Biology Teacher: Lina Martinez

DNA REPARATION

B I B L I O G R A P H Y

• PLOS. (2017, January 26). Quick-and-dirty DNA repair sets the stage for smoking-

related lung cancer. ScienceDaily. Retrieved February 7, 2017 from

www.sciencedaily.com/releases/2017/01/170126142917.htm

• University of Leed. (2017, January 10). Suppressing a DNA-repairing protein in brain could be key to treating aggressive

tumors. ScienceDaily. Retrieved February 7, 2017 from www.sciencedaily.com/releases/

2017/01/170110121046.htm • Martinez Sanchez, Lina Maria. Biología

Molecular. 7 ed. Medellín: UPB. Fac.Medicina

Lung and brain problems are now a step closer to have a therapy and a treatment.

Both news give hope to patient and medical

personal because now there are more studies.The utility for this is huge advance about tumor brain is that scientist can look for

similar proteins all around the body that they can inhibit it and this will give a treatment for another cancer or another problem, also using this protein as a base gives scientists.

About lung cancer, an incredible utility is that knowing what happens to the cell can be

used to recognize those cells earlier so the cancer can be treated before it affects the

whole lung or the whole body. Also this is a pathway to create drugs that inhibits the

wrong reparation, in order to repair just what is good for the cell

Basically, this gives the world a new way to look at the cell reparation.

DNA reparation tries to help the cell when it is affected, so she can keep her genome and she can continue doing the right work for our body. This process start when the cell recognizes the problem so she can correct the damage, and this correction the cell can do it in different ways, for example Base Excision Repair (BER), Nucleotide Excision Repair (NER), the pathway depends on the damage, in this case, if it is a base or a nucleotide.

Sometimes this reparation is what affects the cells, and despite affecting it, this wrong DNA will stay with the daughter cells and it will make a chain of affected cells.

D NA R E PA I R A N D L U N G CA N C E R

The second most common form of lung cancer is the squamous cell carcinoma, which involves

two types of lung stem cells: alveolar progenitor cells and basal cells and

accumulation of DNA.

How they know it? The authors took the cells from the lungs of

smokers and studied their genes, cell division and how the cells repair their DNA.

What did they find? They found that the basal cells were doing the wrong work so they where

trying to repair DNA but this was leading to accumulate it and the

bad thing was that the DNA had so much errors’.

Student’s opinion Knowing the cells that lead to this kind of cancer is an incredible and huge advanced

because it gives the scientists a new way to look at this problem and it will be much

easier to find the cure

D NA R E PA I R I N G P R O T E I N I N

B R A I N The most common type of brain tumor and the most aggressive is the glioblastoma.At the University of Leeds researchersfound that if they inhibited the protein RAD51, the cell was going to die. RAD51 is one of the Glioblastoma Stem Cells which replicates during the treatment and the result is resistance to it.

What did they do? Professor Susan Short at the university explained that radiotherapy affected the DNA ofthe cell but the protein was trying to repair it from the damage, so if they inhibited the protein, the DNA could not repair and the treatment would be more effective.

Do they have any problem? Yes, they do. This experiment has never been done in a human, but they have great expectations.

Student’s opinion Despite being so dangerous, they should make the experiment on humans because tumor's expectations are poor so it would give people at least a chance to survive.

I N T R O D U C T I O N

I N T R O D U C T I O N

N E R B E R

Process that changes a thymine dimer so the

DNA strand can keep the normal sequence.

This process is longer but

more specific, it only changes an specific base.

Q U I C K - A N D - D I RT Y DA N R E PA I R S E T S T H E S TAG E F O R S M O K I N G - R E L AT E D

L U N G CA N C E R

2017, January 26

The basal cells where the principal problem. These cells from smokers, has a patron of replication called ‘transcriptional fingerprint’.

Q U I C K - A N D - D I RT Y DA N R E PA I R S E T S T H E S TAG E F O R S M O K I N G - R E L AT E D L U N G CA N C E R

What leads to carcinoma is a

mutation because of the accumulation of repaired DNA that the cell was doing.

Q U I C K - A N D - D I RT Y DA N R E PA I R S E T S T H E S TAG E F O R S M O K I N G -

R E L AT E D L U N G CA N C E R

This way of reparation is called

‘’non - homologous end

joining’’.

One of the authors, Asselin - Labat, said that their results indicate that targeting DNA repair processes could be a a

pathway to prevent and treat lung cancer.

Q U I C K - A N D - D I RT Y DA N R E PA I R S E T S T H E S TAG E F O R S M O K I N G - R E L AT E D L U N G

CA N C E R

I think, this is an incredible pathway that shows us that when a cell tries

to repair itself, she can make the damage and I think this is important because is a new way to look at the reparation that is not always trying

to help the cell.

Student’s opinion

S U P P R E S S I N G A D NA - R E PA I R I N G P R O T E I N I N B R A I N C O U L D B E K E Y

T O T R E AT I N G AG G R E S S I V E T U M O R S

2017, January 10

S U P P R E S S I N G A D NA - R E PA I R I N G P R O T E I N I N B R A I N C O U L D B E K E Y T O T R E AT I N G AG G R E S S I V E T U M O R S

RAD51 protein is involved in te reparation of DNA double strand breaks and helps the cell to grow. But RAD51 is related to decrease

patient survival when they have cancer.

S U P P R E S S I N G A D NA -

R E PA I R I N G P R O T E I N I N B R A I N C O U L D B E K E Y T O T R E AT I N G AG G R E S S I V E

How did they find the protein RAD51 in glioblastoma cells?

They used inmunofluorescence

microscopy

S U P P R E S S I N G A D NA - R E PA I R I N G P R O T E I N I N B R A I N C O U L D B E K E Y T O T R E AT I N G AG G R E S S I V E T U M O R S

The people between 45 and 75 years are the most affected. The time that they stay alive with cancer is almost 12 - 18 months and only 20% of patients

survive more than one year.

It is important to continue the experiments because they are really close to find the cure of a really big tumor. Also, the fact that radiotherapy is a part of the problem can help to find a different treatment where the help does not induce a bad DNA repair.

Student’s opinion

M E D I C A L U T I L I T Y

M E D I C A L U T I L I T Y

DNA reparation could be useful to correct cells like nervous cell after a disease where part of the mobility is lost. If scientists induce the cell to repair, probably it would help it to

return part of the functioning. Also it could lead to a treatment with RAD51, if the try radiotherapy and the cell try to repair and this could stimulate the

process.

M E D I C A L U T I L I T Y

A great utility would be that scientist can look for similar

tumoral proteins in different cells so the protein could

accelerate the process of reparation or

accumulate the DNA reparation, but a good one that can help the

cell faster.

M E D I C A L U T I L I T Y

Finally, nicotine is what makes the basal cells start to repair

themselves, so it would be an advance to find where this

reparation is good for the cell so nicotine could be a drug so tissues could be repaired in the moment that is found the problem so it

won't affect in the same way the body .

B I B L I O G R A P H Y

• PLOS. (2017, January 26). Quick-and-dirty DNA repair sets the stage for smoking-related lung cancer. ScienceDaily. Retrieved February 7, 2017 from www.sciencedaily.com/

releases/2017/01/170126142917.htm• University of Leed. (2017, January 10). Suppressing a DNA-

repairing protein in brain could be key to treating aggressive tumors. ScienceDaily. Retrieved February 7, 2017

from www.sciencedaily.com/releases/2017/01/170110121046.htm

• Martinez Sanchez, Lina Maria. Biología Molecular. 7 ed. Medellín: UPB. Fac.Medicina

‘ ’ W H AT I S TA N D F O R I S W H AT I S TA N D O N.’’

- Wenddell Berry