A team of researchers from the University of Pittsburgh, lead by Patricia Opresko, Ph.D have discovered crucial new information about telomeres, the end caps of DNA. Telomeres (repeated sequences of DNA) are shortened each time a cell divides, thus becoming smaller with age. When telomeres become too short, they send a signal to the cell to cease dividing permanently – this impairs the ability of tissues to regenerate, contributing to various age-related diseases.
In cancer cells, on the other hand, levels of the enzyme telomerase (which lengthens telomeres) are elevated. This enables them to divide indefinitely. “The new information will be useful in designing new therapies to preserve telomeres in healthy cells and ultimately help combat the effects of inflammation and aging. On the flip side, we hope to develop mechanisms to selectively deplete telomeres in cancer cells to stop them from dividing,” said Dr. Opresko.
Previous studies have shown that oxidative stress accelerates telomere shortening. Oxidative stress is a condition where free radicals build up inside the cell, causing damage. Free radicals can damage the DNA that makes up the telomeres, as well as the DNA building blocks used to extend them. Oxidative stress also plays a role in various other health conditions, including cancer and inflammation. Free radical damage, which is often caused by inflammation in the body, as well as environmental factors, is believed to build up throughout the aging process.
Source: WorldHealth.net.
There are many reasons why in the era of cutting-edge medicine it is still difficult to cure cancer. A tumor may, for instance, consist of different tumor cell sub-populations, each of which has its own profile and responds differently to therapy – or not. Furthermore, the cancer cells and the healthy cells in the body interact and communicate with one another. How a tumor then actually develops and whether metastases form depends on which signals a tumor cell receives from its environment. With the development of a new method a team of researchers has succeeded in comprehensively profiling and visualizing tumor cells from patient samples.