乳癌易感性基因-Brca1的作用机制
BRCA1 is a gene that normally acts to restrain the growth of cells. It suppresses the formation of tumors. Or in the terminology of cancer genetics, BRCA1 is a tumor suppressor. (The symbol BRCA comes from the first two letters of "BReast" and "CAncer".) Mutations (changes) in the BRCA1 gene can make people susceptible to developing breast cancer
NEW YORK, Mar 09 (Reuters Health) -- The breast cancer gene BRCA1 is altered in about half of families with inherited breast cancer and plays a key role in recognizing and repairing damage to other genes. However, exactly how it does this has remained something of a mystery.
, http://www.100md.com
Now scientists from the National Institutes of Health (NIH) report that they have uncovered a clue to BRCA1‘s recognition of genetic damage within cells, taking one step closer to understanding how the gene‘s mutation leads to cancer.
About 5% to 10% of all cases of breast cancer are thought to be due to an inherited susceptibility to cancer, such as a mutation in BRCA1.
In the new study, Dr. Jay H. Chung and colleagues from the NIH in Bethesda, Maryland, looked at the interaction of BRCA1 protein with human Cds1 kinase (hCds1), an enzyme that is involved in genetic repair of cells.
, 百拇医药
The scientists conclude that when DNA is damaged, hCds1 adds phosphorous to one specific region of BRCA1. This step causes BRCA1 to detach from hCds1 and disperse throughout the cell. Apparently this process allows BRCA1 to keep the cell from dividing until the DNA can be repaired. If the damage is not fixed, further damage to the genetic material may lead to cancer.
When BRCA1 was altered so that phosphorus could not attach, hCds1 and BRCA1 remained locked together, even after the cell was damaged with radiation, according to the report in the March 9th issue of Nature.
, http://www.100md.com
More studies showed that adding BRCA1 to cells that were especially sensitive to radiation damage could minimize the destruction. However, when BRCA1 lacked the phosphorus attachment site, the protein provided no protection, the investigators note.
"Understanding how the presence of DNA damage is communicated to tumor suppressors such as BRCA1 is important because it helps us understand how breast and ovarian cancers arise and guides pharmaceutical companies in development of drug targets for cancer therapy," Chung told Reuters Health.
"Although I believe speculations on practical/clinical applications are premature at this point," Chung added, "greater understanding about how cells recognize and repair DNA damage may help us design drugs that improve DNA repair, and drugs that make tumor cells very sensitive to DNA damage, thus making conventional chemotherapy more effective.", 百拇医药
NEW YORK, Mar 09 (Reuters Health) -- The breast cancer gene BRCA1 is altered in about half of families with inherited breast cancer and plays a key role in recognizing and repairing damage to other genes. However, exactly how it does this has remained something of a mystery.
, http://www.100md.com
Now scientists from the National Institutes of Health (NIH) report that they have uncovered a clue to BRCA1‘s recognition of genetic damage within cells, taking one step closer to understanding how the gene‘s mutation leads to cancer.
About 5% to 10% of all cases of breast cancer are thought to be due to an inherited susceptibility to cancer, such as a mutation in BRCA1.
In the new study, Dr. Jay H. Chung and colleagues from the NIH in Bethesda, Maryland, looked at the interaction of BRCA1 protein with human Cds1 kinase (hCds1), an enzyme that is involved in genetic repair of cells.
, 百拇医药
The scientists conclude that when DNA is damaged, hCds1 adds phosphorous to one specific region of BRCA1. This step causes BRCA1 to detach from hCds1 and disperse throughout the cell. Apparently this process allows BRCA1 to keep the cell from dividing until the DNA can be repaired. If the damage is not fixed, further damage to the genetic material may lead to cancer.
When BRCA1 was altered so that phosphorus could not attach, hCds1 and BRCA1 remained locked together, even after the cell was damaged with radiation, according to the report in the March 9th issue of Nature.
, http://www.100md.com
More studies showed that adding BRCA1 to cells that were especially sensitive to radiation damage could minimize the destruction. However, when BRCA1 lacked the phosphorus attachment site, the protein provided no protection, the investigators note.
"Understanding how the presence of DNA damage is communicated to tumor suppressors such as BRCA1 is important because it helps us understand how breast and ovarian cancers arise and guides pharmaceutical companies in development of drug targets for cancer therapy," Chung told Reuters Health.
"Although I believe speculations on practical/clinical applications are premature at this point," Chung added, "greater understanding about how cells recognize and repair DNA damage may help us design drugs that improve DNA repair, and drugs that make tumor cells very sensitive to DNA damage, thus making conventional chemotherapy more effective.", 百拇医药