Future development of targeted cancer drugs could be enhanced by a new study of the telomeric DNA — determinant of cellular lifespan. Researchers from the University of Illinois at Urbana-Champaign, University of Pittsburgh and Yale University conducted the study, which was published in the June 10, 2014, issue of the journal Structure and online at Cell Press.
At the ends of the chromosomes in our DNA molecules are spans of DNA known as telomeres, which protect our genes from damage by ensuring that the chromosomes do not fray or interact with other chromosomes. Each time a cell divides, the telomeres are shortened — aging the cell — until they cannot shorten any more, resulting in the cell’s death.
Cancer cells “overcome this cellular aging by expressing an enzyme called ‘telomerase’ to sustain the telomere length,” says Dr. Sua Myong, who led the study. About 90 percent of all cancer cells activate telomerase. Myong and her team sought to discover the exact molecular mechanism that governs the telomerase loading, so drugs could be targeted to disrupt the telomere extension in cancer cells, effectively destroying them without harming normal cells in which telomerase is mostly inactive.
UI researchers on the project are from the Department of Bioengineering and include: Helen Hwang (M.D./Ph.D.), Alex Kreig (graduate student), Jacob Calvert (undergraduate student), and Dr. Sua Myong, assistant professor. The Illinois team collaborated with Dr. Patricia Opresko and Justin Lormand from the Department of Environmental and Occupational Health at the University of Pittsburgh; and Yongho Kwon, James M. Daley and Dr. Patrick Sung from the Department of Molecular Biophysics and Biochemistry at Yale University.
In related work, Myong’s lab team is developing a way of measuring telomerase quantitatively and digitally in real time to investigate roles of other telomere-binding proteins in controlling the telomerase accessibility and activity.
Cell Press summary (and link to full text):