 |
 | Home | Contact Us | FAQ | Search & Site Map | Link to Us |
 | Sign In | Join | Other 45 Sites in Network |
Medical Forum / General / General / December 2006Aneuploidy Thoery of Cancer
Normal euploid human cells have 23 pairs of chromosomes. Aneuploidy means the cell has an abnormal number and balance of chromosomes, either too many or too few. All solid tumor cancer cells have an abnormal number of chromosomes, usually ranging from 60 to 90. Colon cancer cells contain an average of 79 chromosomes. Cells that have an abnormal number of chromosomes can become cancerous by constantly altering their number and composition in succeeding generations of cells until at some point, perhaps decades later, one of these genetically unbalanced cells turns malignant. And since aneuploidy is inherently unstable, cancer cells continually spawn new cells with differing numbers and assortments of chromosomes and therefore a unique genetic makeup (karyotype). This enables the cancer to survive when threatened by chemotherapy and radiation because a subpopulation of its cells becomes genetically resistant to these challenges. Donald Miller is a cardiac surgeon and Professor of Surgery at the University of Washington in Seattle. He is a member of Doctors for Disaster Preparedness and writes articles on a variety of subjects for LewRockwell.com. His web site is www.donaldmiller.com full text: http://www.lewrockwell.com/miller/miller18.html www.drdach.com > Normal euploid human cells have 23 pairs of chromosomes. Aneuploidy You are a net.kook who insists AIDS is caused by magic and not by HIV: why, then, should anyone give a sh.t about your opinions on cancer? > > Normal euploid human cells have 23 pairs of chromosomes. Aneuploidy > > You are a net.kook who insists AIDS is caused by magic and not by HIV: > why, then, should anyone give a sh.t about your opinions on cancer? Desertphile is a nickname for a deranged anonymous web surfer who is also pathological liar. Since he is anonymous, he can write any nonsense he wants with no accountability, and he does. (as indicated by the above false statement) www.drdach.com >Normal euploid human cells have 23 pairs of chromosomes. Aneuploidy >means the cell has an abnormal number and balance of chromosomes, [quoted text clipped - 10 lines] >threatened by chemotherapy and radiation because a subpopulation of its >cells becomes genetically resistant to these challenges. Well, this is kind of backwards. One of the important steps in carcinogenesis is a mutation that screws up one of the "quality control" mechanisms that prevent or repair copying errors and chromosome defects, or cause the cell to die (apoptosis) if the defect isn't repairable. Once the quality control is bad, all kinds of mutations will get past it, including those to other quality control mechanisms, and things snowball. Chromosomes break, and the broken ends are 'sticky' so pieces get translocated to other chromosomes, and you get the aneuploid mess described above. Aneuploidy is usually a late development in carcinogenesis, not an early one. Malignancy develops when mutations to mechanisms that regulate the cell cycle aren't detected and dealt with appropriately by the quality control mechanisms. At that point the cell may look quite normal, with chromosomes normal in number and appearance. The reasons cancers get resistant to treatment is that in addition to killing cells outright, chemo and radiation can damage DNA without killing the cell. A cell that still has some quality control working can detect the damage and opt to die since it can't effectively repair. A cancer cell that is far advanced won't have this mechanism working, so it will be resistant to the treatment. |
Reply to this Message |
 Sign In
 Join
 My Latest Posts My Monitored Threads My Blog My Photo Gallery My Profile My Homepage Start New Thread Enable EMail Alerts Rate this Thread
|
©2008 Advenet LLC Privacy Policy - Terms of Use
This website includes both content owned or controlled by Advenet as well as content owned or controlled by third parties.