Navigation Links
Low oxygen levels could drive cancer growth
Date:5/3/2012

Athens, Ga. Low oxygen levels in cells may be a primary cause of uncontrollable tumor growth in some cancers, according to a new University of Georgia study. The authors' findings run counter to widely accepted beliefs that genetic mutations are responsible for cancer growth.

If hypoxia, or low oxygen levels in cells, is proven to be a key driver of certain types of cancer, treatment plans for curing the malignant growth could change in significant ways, said Ying Xu, Regents-Georgia Research Alliance Eminent Scholar and professor of bioinformatics and computational biology in the Franklin College of Arts and Sciences.

The research team analyzed samples of messenger RNA dataalso called transcriptomic datafrom seven different cancer types in a publicly available database. They found that long-term lack of oxygen in cells may be a key driver of cancer growth. The study was published in the early online edition of the Journal of Molecular Cell Biology.

Previous studies have linked low oxygen levels in cells as a contributing factor in cancer development, but not as the driving force for cancer growth. High incidence rates of cancer around the world cannot be explained by chance genetic mutations alone, Xu said. He added that bioinformatics, which melds biology and computational science, has allowed researchers to see cancer in a new light. Gene-level mutations may give cancer cells a competitive edge over healthy cells, but the proposed new cancer growth model does not require the presence of common malfunctions such as a sudden proliferation of oncogenes, precursors to cancer cells.

"Cancer drugs try to get to the rootat the molecular levelof a particular mutation, but the cancer often bypasses it," Xu said. "So we think that possibly genetic mutations may not be the main driver of cancer."

Much of cancer research so far has focused on designing drug treatments that counteract genetic mutations associated with a particular type of cancer. In their study, the researchers analyzed data downloaded from the Stanford Microarray Database via a software program to detect abnormal gene expression patterns in seven cancers: breast, kidney, liver, lung, ovary, pancreatic and stomach. The online database allows scientists to examine information from microarray chips, which are small glass slides containing large amounts of gene material.

Xu relied on the gene HIF1A as a biomarker of the amount of molecular oxygen in a cell. All seven cancers showed increasing amounts of HIF1A, indicating decreasing oxygen levels in the cancer cells.

Low oxygen levels in a cell interrupt the activity of oxidative phosphorylation, a term for the highly efficient way that cells normally use to convert food to energy. As oxygen decreases, the cells switch to glycolysis to produce their energy units, called ATP. Glycolysis is a drastically less efficient way to obtain energy, and so the cancer cells must work even harder to obtain even more food, specifically glucose, to survive. When oxygen levels dip dangerously low, angiogenesis, or the process of creating new blood vessels, begins. The new blood vessels provide fresh oxygen, thus improving oxygen levels in the cell and tumor and slowing the cancer growthbut only temporarily.

"When a cancer cell gets more food, it grows; this makes the tumor biomass bigger and even more hypoxic. In turn, the energy-conversion efficiency goes further down, making the cells even more hungry and triggering the cells to get more food from blood circulation, creating a vicious cycle. This could be a key driver of cancer," Xu said.

Xu explained that this new cancer-growth model could help explain why many cancers become drug resistant so quicklyoften within three to six months. He stressed the importance of testing the new model through future experimental cancer research. If the model holds, researchers will need to search for methods to prevent hypoxia in cells in the first place, which could result in a sea change in cancer treatment.


'/>"/>

Contact: Ying Xu
xyn@bmb.uga.edu
706-542-7783
University of Georgia
Source:Eurekalert

Related medicine news :

1. Oxygen in tumors predicts prostate cancer recurrence
2. Cold air chills hearts oxygen supply
3. Extracorporeal membrane oxygenation as a bridge to lung transplantation
4. LSUHSC research shows Rx with hyperbaric oxygen improved TBI and PTSD in vets
5. After Brain Injury, Oxygen Monitoring Vital, Study Finds
6. Gladstone scientists identify gene critical for cell responses to oxygen deprivation
7. Oxygenating Blood of Hospitalized H1N1 Flu Patients Saved Lives: Study
8. Oxygenating system associated with lower risk of death for H1N1 patients with respiratory failure
9. More oxygen in eyes of African-Americans may help explain glaucoma risk
10. Penguins continue diving long after muscles run out of oxygen
11. Higher Oxygen Levels Improve Preemie Survival: Study
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:5/26/2017)... ... , ... Water damage to the flooring of several classrooms at The Fort ... with a number of critical issues to address before students could return to classes. ... little or no disruption to class schedules. Second, the project had to comply with ...
(Date:5/24/2017)... ... May 24, 2017 , ... ... Understanind and choosing the most appropriate instruments for research and understanding the basic ... finding. This webinar will focus on innovations in stereo microscopy for brightfield and ...
(Date:5/24/2017)... Hills, CA (PRWEB) , ... May 24, 2017 , ... ... announced today its participation in nVerge 2017 – a one-day technology conference in San ... Altec’s document management solution, which allows users to fully utilize and enhance their Sage ...
(Date:5/24/2017)... ... May 24, 2017 , ... Drs. ... NY, who have now spent 10 years as clinical instructors for the reputable ... College of Dentistry. Through the program, private practitioners receive cutting-edge clinical training and ...
(Date:5/24/2017)... (PRWEB) , ... May 24, 2017 , ... Patients who ... Cortland, OH, can now meet with Dr. Joseph Bedich for a consultation, with or ... simultaneously improving their oral health and functionality. , Dr. Bedich offers a ...
Breaking Medicine News(10 mins):
(Date:5/9/2017)...  Demonstrating its commitment to representing research- based ... Pharmaceutical Research and Manufacturers of America (PhRMA) today ... now have to meet new research and development ... join PhRMA. "By putting in place ... clear message that being a member of PhRMA ...
(Date:5/9/2017)... Ore. , May 9, 2017  Semler ... that provides technology solutions to improve the clinical ... financial results for the first quarter ended March ... our products enable our customers to identify when ... to intervene before events like heart attacks or ...
(Date:5/8/2017)... 2017  Diplomat Pharmacy, Inc. (NYSE: DPLO)., has completed ... a health care service center company based in ... in relationship management programs for leading pharmaceutical manufacturers and ... WRB will join Envoy Health Management, LLC ... manufacturers, biotech firms, and other service companies. Together, WRB ...
Breaking Medicine Technology: