Study of placenta unexpectedly leads to cancer geneDecember 17, 2008University of Rochester Medical Center scientists discovered a gene mutation that impairs the placenta and also is influential in cancer development, according to a study published online December 16, 2008, in the journal PLoS (Public Library of Science) Biology. The investigation is the first to link the key placental gene, SENP2, to the well-known p53 protein, which is defective in 50 percent of all cancers. Until now, the SENP2 gene's role in early embryo development was not known. As a result of making the connection between SENP2 and the potent cancer stimuli, it will be possible to gain more insight into the complex genetic network involved in cancer, and to develop new therapies, said lead author Wei Hsu, Ph.D., associate professor of Biomedical Genetics and Oncology, of the James P. Wilmot Cancer Center. Hsu and former graduate student Shang-Yi Chiu, currently a postdoctoral fellow at Howard Hughes Medical Institute, Dana-Farber Cancer Institute at Harvard University, have been investigating how cellular signaling triggered by gene mutations affect embryo development in mice. The goal is to better understand the genetic causes and possible treatments for a number of diseases. "What we discovered was an unexpected interaction between an old player, p53, and a new player, SENP2," said Hsu, who also has an appointment in the URMC Center for Oral Biology. SENP2 (SUMO-specific protease 2) is highly expressed in trophoblast cells, which are the stem cells required to form the placenta. The placenta surrounds, protects and nourishes the developing fetus. While investigating disruption of placental formation in a mouse model, Hsu's team observed that embryos lacking SENP2 failed to properly make placental tissue. The failure occurred, researchers discovered, because the cells that give rise to the placental tissues had undergone cell cycle arrest, and were trapped in a state of suspended growth. Next, researchers set out to find SENP2 target proteins that could be involved in arresting cell growth. In the journey, they discovered that p53 - or proteins that modify p53 activity - were harmed by the SENP2 deficiency. The consequence was that p53 could no longer perform its vital job as a tumor suppressor. When p53 is functioning normally, it acts as a crucial guardian of the genome, or a checkpoint, by fixing genetic mistakes as they arise. But when the p53 molecule is aberrantly regulated, either by an outside virus or an inherited genetic abnormality, the risk of cancer is higher because p53 cannot perform its job. Researchers also found that SENP2 indirectly regulates p53 activity through another protein called Mdm2, which was already known to be involved in some cancers. In cells lacking SENP2, the Mdm2 becomes trapped in the nucleus, and is unable to halt p53, allowing it to accumulate within the cell. This disruption leads to distinct problems in cell cycle progression and normal gene replication. University of Rochester Medical Center |
|||||||||||||||||||||
| Related Cancer Gene Current Events and Cancer Gene News Articles Researchers chart genomic map spanning over 2 dozen cancers An international team of researchers has created a genome-scale map of 26 different cancers, revealing more than 100 genomic sites where DNA from tumors is either missing or abnormally duplicated compared to normal tissues. Sorting the drivers from the passengers in the cancer genome A new study of mutations in cancer genomes shows how researchers can begin to distinguish the 'driver' mutations that push cells towards cancer from the 'passenger' mutations that are a by-product of cancer cell development. Lung cancer and melanoma laid bare Research teams led by the Wellcome Trust Sanger Institute announce the first comprehensive analyses of cancer genomes. Understanding DNA Repair and Cancer A protein that plays a key role in copying DNA also plays a vital role in repairing breaks in it, UC Davis scientists have found. Mammography may increase breast cancer risk in some high-risk women Low-dose radiation from annual mammography screening may increase breast cancer risk in women with genetic or familial predisposition to breast cancer, according to a study presented today at the annual meeting of the Radiological Society of North America (RSNA). New cancer gene discovered A new cancer gene has been discovered by a research group at the Sahlgrenska Academy. The gene causes an insidious form of glandular cancer usually in the head and neck and in women also in the breast. The discovery could lead to quicker and better diagnosis and more effective treatment. Newly Discovered Gene Fusion May Lead to Improved Prostate Cancer Diagnosis Researchers from NewYork-Presbyterian Hospital/Weill Cornell Medical Center have discovered a new gene fusion that is highly expressed in a subset of prostate cancers. Wet ear wax and unpleasant body odors signal breast cancer risk If having malodorous armpits (called osmidrosis) and goopy earwax isn't bad enough, a discovery by Japanese scientists may add a more serious problem for women facing these cosmetic calamities. Gene signature helps predict breast cancer prognosis Vanderbilt-Ingram Cancer Center researchers have uncovered a gene signature that may help predict clinical outcomes in certain types of breast cancer. Reversing effects of altered enzyme may fight brain tumor growth An international team of scientists from the Moores Cancer Center at the University of California, San Diego, the University of North Carolina and several institutions in China have explained how a gene alteration can lead to the development of a type of brain cancer, and they have identified a compound that could staunch the cancer's growth. More Cancer Gene Current Events and Cancer Gene News Articles |
|||||||||||||||||||||
|
|||||||||||||||||||||
|
|||||||||||||||||||||