Dna Repair Mechanisms

1. DNA REPAIR
MECHANISMS
MARIA CLARA OCHOA PATIÑO
MEDICINE STUDENT
THIRD SEMESTER

2. DNA REPAIR
MECHANISMS
MARIA CLARA
OCHOA PATIÑO
MOLECULAR
BIOLOGY
UPB
2017
MEDICAL UTILITY
Both news items
mentioned above have
great medical
applications.
These advances in
science will bring
countless benefits to the
treatment and
prevention of various
diseases associated with
failures in DNA
replication and repair
mechanism.
BIBLIOGRAPHY
♪ Martínez Sánchez, Lina
María. Biología Molecular.
7 ed. Medellín: UPB. Fac.
Medicina
♪ University of Pennsylvania
School of Medicine. (2017,
July 31). How DNA damage
turns immune cells against
cancer. ScienceDaily.
Retrieved August 22, 2017
from
https://www.sciencedaily.c
om/releases/2017/07/1707
31164119.htm
♪ University of North
Carolina Health Care
(2017, June 12). Where
cigarette smoking's
damage is done--down to
your DNA. ScienceDaily.
Retrieved August 23,
2017 from
https://www.sciencedaily
.com/releases/2017/06/1
70612170919.htm

3. INTRODUCTION
DNA is constantly exposed to
a variety of factors that can
damage it and affect its
structure as errors occurred
during replication or physical
and chemical agents. For this
reason, the cells have
developed specialized
mechanisms of detection and
repair of this damages, that
have as main function to keep
the genome intact and to
avoid alterations in the genes
of the daughter cells.
Researchers at the University of
Pennsylvania have discovered how
DNA damage is a clear call to the
immune system.
They propose the use of this
information to design new
treatments that include the use of
the immune cells and inhibitors of
the replication to control the
development of the cancerous cells
until they die, obtaining a better
response of the patients to the
treatment.
PERSONAL OPINION
This seems to be a very
practical alternative for the
treatment of cancer because
it is a way to keep the
cancerous cells controlled
using the body's own
resources, although with
more advances, it could
replace the treatment with
external agents that in
many cases are toxic.
Scientists at the University of
North Carolina created a method
to effectively mapping DNA
damage caused by cigarette
smoking across the genome.
Dr. Sancar and his team have
developed a useful technique for
mapping sites on the genome
that are undergoing repair
following the common type of
DNA damage, after, they used
that technique to map all
damage caused by the major
chemical carcinogen of cigarette:
benzo [α] pyrene.
PERSONAL OPINION
HOW TO DNA DAMAGE
TURNS IMMUNE CELLS
AGAINST CANCER
WHERE CIGARETTE
SMOKING’S
DAMAGE IS DONE—
DOWN TO YOU DNA
This is an important advance that
contributes to the understanding
of the effects of the cigarette in the
genome and will be of great help
in the prognosis of the alterations
and pathologies that cause
prolonged exposure to
carcinogens present in cigarettes
and other products of frequent use
in population.

4. INTRODUCTION
EXPLANATION
In the introduction we talk about the damages that
can be suffer DNA, their possible causes and explain
the mechanisms that had to develop the cells to repair
self and prevent that alterations are transmitted to
their daughter cells.
It is important to understand this concept and to
know that any failure in these mechanisms can lead to
malfunctioning of cells and explain the behavior of
diseases such as cancer.
A number of types of DNA repair mechanisms are
known among those who are:
♪ Direct reversal of damaged DNA
♪ Excision Repair (BER and NER)
♪ Repair Double Helice Break
INTRODUCTION
DNA is constantly exposed to
a variety of factors that can
damage it and affect its
structure as errors occurred
during replication or physical
and chemical agents. For this
reason, the cells have
developed specialized
mechanisms of detection and
repair of this damages, that
have as main function to keep
the genome intact and to
avoid alterations in the genes
of the daughter cells.

5. HOW TO DNA DAMAGE
TURNS IMMUNE CELLS
AGAINST CANCER
JULY 31, 2017. UNIVERSITY OF PENNSYLVANIA
HOW TO DNA DAMAGE
TURNS IMMUNE CELLS
AGAINST CANCER
Researchers at the University of
Pennsylvania have discovered how
DNA damage is a clear call to the
immune system.
They propose the use of this
information to design new
treatments that include the use of
the immune cells and inhibitors of
the replication to control the
development of the cancerous cells
until they die, obtaining a better
response of the patients to the
treatment.
PERSONAL OPINION
This seems to be a very
practical alternative for the
treatment of cancer because
it is a way to keep the
cancerous cells controlled
using the body's own
resources, although with
more advances, it could
replace the treatment with
external agents that in
many cases are toxic.

6. HOW TO DNA DAMAGE TURNS IMMUNE
CELLS AGAINST CANCER
Cancer is a disease of the cell
replication cycle. The objective
of treatments with
chemotherapy or radiation is to
cause irreparable damage to
these malignant cells to die and
do not return to proliferate.
* But cancer cells can use DNA
repair mechanisms to try to
counteract the damage suffered
and survive.

7. HOW TO DNA DAMAGE TURNS IMMUNE
CELLS AGAINST CANCER
If a cell's DNA is damaged, it
stalls for about 24 hours at a
point in the cell replication
cycle. Cells resume dividing as
they eventually overcome their
wounds, and this leads to
activation of signals that
attracts the immune system.
* The study describes that
after damage to the DNA by
therapy, small packets of extra
nuclear DNA are formed
which tend to breaks and
activate a special surveillance
protein that causes a similar
response of immune cells as
would occur when exist a viral
infection.

8. In conclusion, the study
reveals that changes in
the rate of division of a
cancer cell are an
important
consideration for
cancer therapies that
combine DNA damage
and immune
checkpoint inhibitors.
HOW TO DNA DAMAGE TURNS IMMUNE
CELLS AGAINST CANCER

9. PERSONAL OPINION
It seems to me an excellent
advance in the field of the fight
against the cancer, because with
this information they are
propitiated more possibilities of
alternative treatments less
invasive and exhausting for the
organism of the patients. Also,
this type of study allows us to
improve our understanding of
how the disease works and what
other alternatives we have to treat
it.

10. JUNE 12, 2017. UNIVERSITY OF NORTH CAROLINA
WHERE CIGARETTE SMOKING’S
DAMAGE IS DONE—DOWN TO YOU
DNA
WHERE CIGARETTE
SMOKING’S
DAMAGE IS DONE—
DOWN TO YOU DNA
Scientists at the University of
North Carolina created a method
to effectively mapping DNA
damage caused by cigarette
smoking across the genome.
Dr. Sancar and his team have
developed a useful technique for
mapping sites on the genome
that are undergoing repair
following the common type of
DNA damage, after, they used
that technique to map all
damage caused by the major
chemical carcinogen of cigarette:
benzo [α] pyrene.
PERSONAL OPINION
This is an important advance that
contributes to the understanding
of the effects of the cigarette in the
genome and will be of great help
in the prognosis of the alterations
and pathologies that cause
prolonged exposure to
carcinogens present in cigarettes
and other products of frequent use
in population.

11. WHERE CIGARETTE SMOKING’S DAMAGE IS
DONE—DOWN TO YOU DNA
Benzo [α] pyrene (BaP) is a member of a
family of simple hydrocarbons. For humans
the BaP poses a serious problem because this
is a carcinogen responsible for about 30
percent of cancer deaths in the United States,
this is very serious because this substance is
present not only in cigarettes also in the
environment due to pollution.
Usually when a toxic agent enters our body,
many tissues enzymes act to degrade it
immediately but with many substances such
as BaP in these protection reactions generate
reactive metabolites as the BPDE which are
the cause of increased toxicity.
BPDE chemically reacts with DNA, forming a
very close link in the nucleobase guanine. This
link means that genes cannot make adequate
protein and DNA can not be correctly
replicated during cell division.

12. WHERE CIGARETTE SMOKING’S DAMAGE IS
DONE—DOWN TO YOU DNA
In Repair Excision Nucleotides
(NER). Protein specific cut the
affected DNA strand, then the
enzymes that synthesize DNA
reconstruct the missing section of
DNA copying the sequence of
another strand unaffected, but the
cut section of the DNA float until is
to be eliminated.
* These pieces of DNA that float
and have not been removed are the
detected by Sancar team mapping
technology, ultimately the
scientists obtained a map of the
sites where DNA repairs have
begun.

13. WHERE CIGARETTE SMOKING’S DAMAGE IS
DONE—DOWN TO YOU DNA
“ Understanding this bias in repair
should help us better understand
why exposures to toxins such as
BaP tend to cause certain gene
mutations.”
─ Wentao Li
“ This new method can be applied
to any type of DNA damage that
involves nucleotide excision repair.”
─ Aziz Sancar

14. PERSONAL OPINION
I am very happy to know that this
type of progress is being developed
in the scientific field because it is
important to understand the
consequences of our life habits on
our health and can be a call not
only to the smokers also the people
who contribute to pollution.
It is an incredible advance that will
allow us to predict with certainty
the alterations caused by a great
quantity of substances.

15. MEDICAL UTILITY
Both news items
mentioned above have
great medical
applications.
These advances in
science will bring
countless benefits to the
treatment and
prevention of various
diseases associated with
failures in DNA
replication and repair
mechanism.
It is important to know in
depth the physiological and
molecular processes of
diseases to achieve a more
efficient treatment that does
not generate secondary
damages or contribute to the
deterioration of our patients,
with these scientific
discoveries we are each closer
to achieving it.
MEDICAL UTILITY

16. MEDICAL UTILITY
All this information will lead to a better understanding of
why some people are predisposed to certain diseases such
as cancer, the genetic component of them and the fact that
mutations are closely related to exposure to certain
substances.

17. MEDICAL UTILITY
Both news reports inform us
about theories about how we
can deal with diseases that are
closely related to the human
genome, show us the
techniques and possible
treatments that we must
experiment in a broader way
to combat them and give us
solid arguments about the
etiology of diseases that a few
years ago they were
misunderstood.

18. MEDICAL UTILITY
Finally, all of these findings will help the medical community to improve
traditional treatments, make stronger prevention campaigns about inadequate
lifestyle and their relationship to the increased likelihood of acquiring certain
diseases, especially cancer. In addition, it will draw the attention of people who do
not consider it important to live in healthy and pollution-free environments.

19. BIBLIOGRAPHY
♪ Martínez Sánchez, Lina María.
Biología Molecular. 7 ed. Medellín:
UPB. Fac. Medicina
♪ University of Pennsylvania School
of Medicine. (2017, July 31). How
DNA damage turns immune cells
against cancer. ScienceDaily.
Retrieved August 22, 2017 from
https://www.sciencedaily.com/rele
ases/2017/07/170731164119.htm
♪ University of North Carolina
Health Care (2017, June 12).
Where cigarette smoking's damage
is done--down to your
DNA. ScienceDaily. Retrieved
August 23, 2017 from
https://www.sciencedaily.com/rele
ases/2017/06/170612170919.htm

20. “ENJOY THE RIDE,
LOVE THE ENDING”
─ ANONYMOUS