Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Study of hypoxia and new gene reveals early-stage action of p53 tumor suppressor gene

05.01.2005


Researchers have known for a decade that the p53 tumor suppressor gene is important for killing cells as they proliferate under low-oxygen conditions inside tumors. As tumors grow they outstrip their oxygen supply. If a cell has a normal p53 gene, the p53 protein will eliminate cancerous cells, keeping tumor growth at bay. Under conditions of stress to the cell – such as radiation or chemotherapy and hypoxia – p53 normally eliminates tumors.


Composite of action of Buip3L and p53 under hypoxia.



Hypoxia, however, induces p53 to mutate: The less oxygen, the more mutations in the p53 gene, so cancer cells are not killed; instead, they proliferate. A team led by Wafik El-Deiry, MD, PhD, Associate Professor, Departments of Medicine, Genetics, and Pharmacology with the Abramson Cancer Center of the University of Pennsylvania, discovered a gene related to p53 called Bnip3L that can also cause cell death. The gene is turned on by p53 and a second transcription factor called hypoxia inducible factor, or HIF. The team silenced Bnip3L in cells with normal p53 and exposed cells to low oxygen conditions. In cell culture and in an animal model with implanted tumor cells, the researchers showed that tumors with silenced Bnip3L grew more aggressively in low oxygen conditions than cells and tumors with intact Bnip3L. El-Deiry and first author Peiwen Fei, MD, PhD, a post-doctoral fellow, report their findings in the December issue of Cancer Cell.

"From this, we predict in humans that another reason for tumor growth is the silencing of Bnip3L," says El-Deiry. "We think one of the ways that p53 suppresses tumors at their earliest stages is by turning on Bnip3L, and that’s new. There is no information at present about how p53 works in the earliest stages of tumor growth, especially as the growth begins to outstrip the supply of nutrients and oxygen."


Understanding how cells die after they are starved for oxygen is important for fighting cancer as well as other diseases. "Down the road we would like to find strategies to turn Bnip3L back on to restore the ability to die under hypoxia now that we know how it happens in the first place," says El-Deiry.

Karen Kreeger | EurekAlert!
Further information:
http://www.uphs.upenn.edu

More articles from Life Sciences:

nachricht Climate Impact Research in Hannover: Small Plants against Large Waves
17.08.2018 | Leibniz Universität Hannover

nachricht First transcription atlas of all wheat genes expands prospects for research and cultivation
17.08.2018 | Leibniz-Institut für Pflanzengenetik und Kulturpflanzenforschung

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Color effects from transparent 3D-printed nanostructures

New design tool automatically creates nanostructure 3D-print templates for user-given colors
Scientists present work at prestigious SIGGRAPH conference

Most of the objects we see are colored by pigments, but using pigments has disadvantages: such colors can fade, industrial pigments are often toxic, and...

Im Focus: Unraveling the nature of 'whistlers' from space in the lab

A new study sheds light on how ultralow frequency radio waves and plasmas interact

Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...

Im Focus: New interactive machine learning tool makes car designs more aerodynamic

Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.

When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...

Im Focus: Robots as 'pump attendants': TU Graz develops robot-controlled rapid charging system for e-vehicles

Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.

Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....

Im Focus: The “TRiC” to folding actin

Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.

Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

LaserForum 2018 deals with 3D production of components

17.08.2018 | Event News

Within reach of the Universe

08.08.2018 | Event News

A journey through the history of microscopy – new exhibition opens at the MDC

27.07.2018 | Event News

 
Latest News

Smallest transistor worldwide switches current with a single atom in solid electrolyte

17.08.2018 | Physics and Astronomy

Robots as Tools and Partners in Rehabilitation

17.08.2018 | Information Technology

Climate Impact Research in Hannover: Small Plants against Large Waves

17.08.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>