ALEJANDRO CARDONA PALACIOMEDICINE STUDENT

OVEREXPRESSION OF REPETITIVE DNA SEQUENCES DISCOVERED IN COMMON

TUMOR CELLS AND SINGLE CELL STUDIES IDENTIFY COACTIVATOR ROLE IN FAT CELL

MATURATION  

Introduction DNA sequences -- called satellite

repeats -- is very active in cancer but not

in normal tissue.  

Pancreatic cancer cells were correctly identified on the basis

of the expression of satellite RNA.

PPAR gamma is known to regulate the production of adipocytes or fat cells. It

regulates transcription -- making an RNA copy of DNA. 

Some drugs used to treat type 2 diabetes increase the activity of PPAR gamma and this increased abdominal fat and, more recently, cardiovascular complications.

OVEREXPRESSION OF REPETITIVE DNA SEQUENCES DISCOVERED IN COMMON

TUMOR CELLS(ScienceDaily. February 28,2011)

Active in cancer but

not in normal tissue.

Common tumor cells

Overexpression of certain DNA sequences that do not code for

proteins -called satellite

repeats -

Analyzed samples

Mouse model of pancreatic cancer

Find that satellite DNA was expressed at levels more

than 100 times what would be expected in normal

tissues.

Greatly increased satellite

expression was also found in

mouse colon and lung tumors

Analysis of human tumor samples produced similar

results

With powerful overexpression

of two satellites called HSATII and ALR in the majority

of cancers studied

tumors of the pancreas, lung, prostate

Pancreatic cancer cells

Were correctly identified based on satellite RNA expression, which was appreciably higher than in nonmalignant cells.

If confirmed in large prospective

clinical trials.

Satellite RNA expression may provide a new and highly specific biomarker relevant

to multiple types of epithelial cancers.

Daniel Haber, says………

"What is most remarkable is how such a dramatic abnormality was only revealed because of new powerful sequencing technologies that allow us to study a type of RNA that was previously discarded”

“Our hope is that this abnormality will serve as an important biomarker in cancer diagnosis and that it will also shed light on common mechanisms by which cancer develops."

STUDENT OBSERVATION: NEWS Nº 1

Using powerful new DNA analysis techniques to achieve more satellite significant progress in this

field in order to understand and analyze the molecular form different types of cancer and thus provide a possible development of a cure for this

disease.

Digital gene expression analysis system called single

molecule next-generation sequencing

New insights into the formation, growth of

malignant cells responsible for this

disease.

Hartig said reduced levels of SRC-2 and 3 resulted in more

cells with low levels of lipid and increased PPAR gamma.

Are a group of nuclear receptor proteins that function as transcription factors regulating the

expression of genes.

PPAR gamma

PPARs play essential roles in the regulation of cellular differentiation, development and metabolism (carbohydrate, lipid, protein) and tumorigenesis of higher organisms.

Steroid receptor coactivator

PPAR gamma (peroxisome proliferator activated receptor gamma)

Can vary widely, but the fat cells (adipocytes)

Can maintain stable levels of master switches known as steroid receptor coactivators (SRC)-2

and -3.

….is known to regulate the production of adipocytes or fat cells

… regulates transcription -- making an RNA copy of DNA, which is the first step in gene expression.

… and linear connection between PPAR gamma transcriptional regulator and lipids in a cell.

PPAR gamma …

PPAR gamma

STUDENT OBSERVATION: NEWS

Nº 2

It should further investigate the importance of PPAR gamma in the treatment of diseases such as diabetes, obesity, and the central nervous system and from this to an approach to future

scientific discoveries around the field.

Have evidence that these receptors (PPAR) are involved in neuronal

differentiation and protection and are potential pharmacological targets in the treatment of neurodegenerative

diseases.

For Example in the central

nervous system

MEDICAL UTILITY

DNA sequences -- called satellite repeats -- have

been studied for their role in chromosome structure, to take an active role in cancer, The search for greater expression of satellite in low-grade tumors showed that

overexpression begins early in tumor

development, which has implications for early

detection.By analysis showed that pancreatic cancer cells were correctly identified

on the basis of the expression of satellite

RNA, which was significantly higher than in

nonmalignant cells.

First News

DNA sequenc

es

Role in chromosome

structure

Identify Cancer

Pancreas Lung

sEpitheli

al

FOR EXAMPLE….

Cancer cells

Were correctly identified on the basis of the expression of

satellite RNA

Malignant cancer is a tumor in which an aggregation of individual cells begin to grow in a rapid, uncontrolled and abnormal manner and

it is now understood that cancer is caused by the mutations of a gene which confer increased

abnormal growth potential to cells.

Some drugs used to treat type 2 diabetes increase the activity of PPAR

gamma. These include the thiazolidines such as Actos and Avandia, which

increase the levels of genes associated with sensitivity to insulin.

PPAR gamma is known to regulate the production of adipocytes or fat cells. It regulates transcription --

making an RNA copy of DNA, which is the first step in gene expression

--

MEDICAL UTILITY

PPAR gamma stimulates fat cell production, these

drugs can also lead to increased

abdominal fat and, more recently, cardiovascular complications.

PPAR gamma is known to regulate the production

of adipocytes or fat cells. It regulates transcription -- making an RNA copy of

DNA, which is the first step in gene expression

and is important because some drugs used to treat type 2 diabetes increase

the activity of PPAR gamma. These include

the thiazolidines such as Actos and Avandia, which

increase the levels of genes associated with sensitivity to insulin.

However, because PPAR gamma stimulates fat cell production, these drugs can also lead to

increased abdominal fat and, more recently,

cardiovascular complications.

 

Second News

has been implicated in the pathology of numerous diseases including

obesity, diabetes, atherosclerosis and cancer.

PPAR-gamma agonists have been used in the treatment of

PPAR-gamma decreases the inflammatory response of many cardiovascular cells, particularly endothelial cells.

dyslipidaemia

hyperglycemia.

PPAR-gamma activates the PON1 gene, increasing synthesis and

release of paraoxonase from the liver, reducing atherosclerosis.

PPAR-gamma

BIBLIOGRAPHY

Science. “Overexpression of Repetitive DNA Sequences Discovered in Common Tumor Cells ”. ScienceDaily. January 13, 2011.

Baylor College of Medicine.“Single Cell Studies Identify Coactivator Role in Fat Cell Maturation”. ScienceDaily. January 11, 2011.

Joaquin Luco´s Center For Cell Regulation and Pathology. Peroxisome proliferator-activated receptor. [Consulta: 23January 2010]. < Available at http://fondap-crcp.cl/investigacion.php?id=20>.