A cancer gene causing tumours by a 'double-whammy' mechanism also reveals the key to a cureJanuary 21, 2004Scientists at the Babraham Institute have discovered that a tiny change in a protein involved in cell survival is responsible for abnormal cell activity in the early stages of cancer. The protein, known as Bcl-xL, normally protects cells from dying; and when the DNA in cells becomes damaged, Bcl-xL is modified so that it no longer keeps the cells alive. Hence, the cells with damaged DNA usually die, so preventing them from becoming cancer cells. However, in the presence of a particular cancer gene, the usual modification of Bcl-xL following DNA damage doesn't occur, so cells with DNA damage are kept alive, resulting in cancer. The discovery, described in an article in Cancer Cell published today (19 January), was made by Dr Rui Zhao, working in Dr Denis Alexander's research group at the Babraham Institute, Cambridge. Sharp-eyed Dr Zhao noticed that the tiny change in Bcl-xL that normally occurs after exposing cells to radiation no longer happened when the particular cancer gene was present. "The cancer model that we're working on is T cell lymphomas", Dr Alexander explains, "but it's quite likely that this mechanism could be relevant to other types of cancer as well - 24,500 people in Britain every year are diagnosed with a cancer of the blood". Intriguingly, the cancer gene being studied at the Babraham Institute (a hyperactive tyrosine kinase) acts by a 'double-whammy' mechanism. In the first instance, it inhibits the rapid repair of DNA damage that often occurs as cells divide. Therefore DNA damage quickly begins to accumulate in cells containing the cancer gene. Additionally, the cancer gene prevents the cells with damaged DNA from being eliminated, so leading to cancer. "It is quite likely", says Dr. Alexander, "that if only one of these mechanisms were taking place, there would be no cancer. It's when both occur simultaneously, the 'double-whammy', that the catastrophe happens". Understanding how the cancer gets going in the first place might eventually lead to novel cancer therapies. Dr. Alexander's group has also shown that the critical modification of Bcl-xL, prevented by the cancer gene even before the cancer gets started, also remains blocked in tumours even when they've been exposed to reagents used in chemotherapy. "If we could find a way of averting this blockade", Dr. Alexander comments, "then the power of Bcl-xL in keeping tumour cells alive would be destroyed, and the tumour would either spontaneously die or would at least become more sensitive to chemotherapy or radiotherapy". "We are delighted to see such breakthroughs in cancer research", the Director Dr. Richard Dyer commented, "as this highlights the commitment of the Institute to investigate the basic biological mechanisms that underlie disease". | |||||||||||||||||||||
|
Related DNA Current Events and DNA News Articles Genetic breakdown in Fanconi anemia may have link to HPV-associated cancer A genetic malfunction that causes DNA instability in people with the blood disorder Fanconi anemia may put them at high risk for squamous cell carcinomas linked to human papillomavirus (HPV), according to a study posted online ahead of print by Oncogene. Plants display 'molecular amnesia' Plant researchers from McGill University and the University of California, Berkeley, have announced a major breakthrough in a developmental process called epigenetics. They have demonstrated for the first time the reversal of what is called epigenetic silencing in plants. Research in twins defines shared features of the human gut microbial communities: variations linked to obesity Trillions of microbes make their home in the gut, where they help to break down and extract energy and nutrients from the food we eat. Yet, scientists have understood little about how this distinctive mix of microbes varies from one individual to the next. Tool Helps Identify Gene Function in Soybeans, Could Lead to Better Crop Performance, say MU Researchers In the race for bioengineered crops, sequencing the genome could be considered the first leg in a multi-leg relay. Brown Chemist Finds Gene That Enables Gray Mold to Kill Plant Cells Gray mold is a gardener's nightmare. The fungus, also known by its scientific name Botrytis cinerea, is a scourge to more than 200 agricultural and ornamental plant species, including staples such as tomatoes, strawberries, snap and lima beans, cabbage, lettuce and endive, peas, peppers, and potatoes. Ice beetles impacted by climate change In the summer of 1968, Dave Kavanaugh set off on a hike that would change the course of his life. As a second-year medical student at the University of Colorado, he had joined a climbing club with a few members of the biophysics department, and the group had set their sights on Gray's Peak-the ninth highest mountain in Colorado. Fruit fly research may lead to better understanding of human heart disease Researchers at the Burnham Institute for Medical Research (Burnham) have shown in both fruit flies and humans that genes involved in embryonic heart development are also integral to adult heart function. The study, led by Rolf Bodmer, Ph.D., was published in Proceedings of National Academy of Sciences. CSHL scientists discover a new way in which epigenetic information is inherited Hereditary information flows from parents to offspring not just through DNA but also through the millions of proteins and other molecules that cling to it. Synthetic virus supports a bat origin for SARS SARS - severe acute respiratory syndrome - alarmed the world five years ago as the first global pandemic of the 21st century. The coronavirus (SARS-CoV) that sickened more than 8,000 people - and killed nearly 800 of them - may have originated in bats, but the actual animal source is not known. Scripps Research Scientists Shed Light on How DNA Is Unwound So That Its Code Can Be Read Researchers at The Scripps Research Institute have figured out how a macromolecular machine is able to unwind the long and twisted tangles of DNA within a cell's nucleus so that genetic information can be "read" and used to direct the synthesis of proteins, which have many specific functions in the body. More DNA Current Events and DNA News Articles |
|||||||||||||||||||||
|
|||||||||||||||||||||
|
|||||||||||||||||||||