Biomolecular News By Daniel Gallego González

Medicine Student

III Semester

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FRONT FACE 2

BACK FACE 3

INTRODUCTION

When living cells divide, each

daughter cell must receive a copy

of the genome, for that reason the

DNA must be replicated.

The DNA replication is a critical

process that can trigger several

disease if it is unsuccessful. For that

reason, this process is studied to

treat pathologies such as cancer.

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FIRST NOTICE 5

Cambridge researchers have

published a that four-stranded

‘quadruple helix’ DNA structures

known as G-quadruplexes also

exist within the human genome.

¿WHAT DOES THE “G” MEAN?

It indicates that the ‘quadruple

helix’ is present in regions of DNA

rich in guanine.

The research pretends to show

clear links between

concentrations of four-stranded

quadruplexes and the process of

DNA replication.

This quadruplexes are more

likely to occur in genes of cells

that are rapidly dividing,

such as cancer cells.

FIRST NOTICE 6

Professor Shankar

Balasubramanian from

the University of Cambridge's

Department of Chemistry and

Cambridge Research Institute:

FIRST NOTICE 7

“We are seeing links

between trapping the

quadruplexes with

molecules and the ability

to stop cells dividing, which

is hugely exciting”.

FIRST NOTICE 8

The ‘quadruple helix’ DNA structure may well

be the key to new ways of selectively inhibiting

the proliferation of cancer cells.

2. Fluorescence to

mark the antibodies.

1. Antibody proteins that

detect and bind to

G-quadruplexes.

3. Could stop carcinogen

cells’ proliferation.

PERSONAL COMMENT 9

SECOND NOTICE 10

Research by scientists at the

National Cancer Institute has

identified a new class of DNA

sites in cells that break early

in the replication process.

This research was headed by

Andre Nussenzweig, chief of

the Laboratory of Genome

Integrity, Center for Cancer

Research, NCI.

SECOND NOTICE 11

Some genes that comprise DNA strands increase the risk

for cancer, induce replication stress, and result in a higher

likelihood of cells acquiring DNA damage, such as breaks.

It was found that these break sites correlate

with damage often seen in B cell cancers, such as

diffuse large B cell lymphoma.

DNA REPLICATION DNA BREAKS LYMPHOMA

SECOND NOTICE 12

They used the mouse immune

system as a model, isolated

healthy cells, and then monitored

the cells for initiation of DNA

damage in order to understand

how a healthy cell mutated.

The scientists then

compared the DNA damage

sites in their mouse model

with sites mutated in

human diffuse large B cell

lymphoma tissue samples.

It was found that both

mouse and human cells

exhibit similar trends

of genome instability.

SECOND NOTICE 13

PERSONAL COMMENT

Again, advances in molecular biology allow

us to understand the etiologic origin of many

diseases and offer new alternatives for its

diagnosis and treatment. The B cell cancers, such

as diffuse large B cell lymphoma, had never been

completely understood. For that reason, this

research will help too many people with this

diseases, approaching to a possible cure.

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MEDICAL BENEFIT 15

Genetics and Molecular Biology

provide to Medicine new

alternatives for the treatment

of complicated diseases, which

were believed that had no cure.

Is very important to study the

DNA replication to understand

the origin and development of

diseases that previously had no

explanation, and therefore

could not be treated.

The research of the

G-quadruplex DNA

structure, will allow the

trapping of cells with a high

level of replication such as

carcinogen ones, for

stopping and destroying

them, which could be a new

cure for cancer in a

molecular level.

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From this latest research in B

cell cancer, some instability in

specific genetic sequences has

been recognized, giving rise to a

possible genetic intervention

to help people with this

aggressive disease.

Undoubtedly, the DNA replication is a complicated process

that is vulnerable to several damages.

There are many diseases that arise from problems in

this cellular process. In order to prevent them, this

kind of investigations are essential to understand the

causes and to get the solutions.

MEDICAL BENEFIT 18

ARTICLES 1. G-quadruplexes also exist within the human genome [Internet].

Cambridge: University of Cambridge; 2013. [Consulted at January

29th, 2013].

2. DNA breaks early in replication process associated with B cell

cancers [Internet]. Bethesda: National Cancer Institute; 2013.

[Consulted at February 29th, 2013].

BIBLIOGRAPHY 1. CLARK, David; PAZDERNIK, Nanette. Molecular Biology. 2. ed.

Oxford: Elsevier Inc, 2013. 274-276 p.

2. KUNDU, Tapas. Epigenetics: Development and disease. Bangalore:

Molecular biology and genetics unit Jawaharlal Nehru Centre for

Advanced Scientific Research. Springer, 2013. 57-58 p.

3. BHAGAVAN, N; CHUNG-EUN, Han. Essentials of Medical

Biochemistry. London: Elsevier Inc, 2011. 294-295 p.

REFERENCES 19

By Daniel Gallego González,

Cañón del Chicamocha,

Santander, 2011.

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