Following is an in-depth exploration of telomeres.
Telomeres are on the ends of chromosomes. They can be compared to the plastic tips on shoelaces. Telomeres keep chromosome ends from fraying and sticking to each other, which destroys or scrambles an organism's genetic information.
Each time a cell divides, the telomeres get shorter. When they get too short, the cell can no longer divide; it becomes inactive or "senescent", or it dies. This shortening process is associated with aging, diseases, and a higher risk of death. Scientists have discovered that telemorase, an enzyme, keeps telomeres from shortening.
Cellular aging, or senescence, is the process by which a cell becomes old and dies. It is due to the shortening of chromosomal telomeres to the point that the chromosome reaches a critical length. Cellular aging is analogous to a wind up clock.
If the clock stays wound, a cell becomes immortal and constantly produces new cells. If the clock winds down, the cell stops producing new cells and dies. Our cells are constantly aging. Being able to make the body's cells live forever certainly creates some exciting possibilities. Telomerase research could therefore yield important discoveries related to the aging process.
Cancer cells are a type of malignant cell. The malignant cells multiply until they form a tumor that grows uncontrollably. Telomerase has been detected in human cancer cells and is found to be 10-20 times more active than in normal body cells. This provides a selective growth advantage to many types of tumors. If telomerase activity was to be turned off, then telomeres in cancer cells would shorten, just like they do in normal body cells. This would prevent the cancer cells from dividing uncontrollably in their early stages of development.
In the event that a tumor has already thoroughly developed, it may be removed and anti-telomerase therapy could be administered to prevent relapse. In essence, preventing telomerase from performing its [unnatural] function would change cancer cells from "immortal" to "mortal". [Thus curing the disease.]
Knowing what we have just learned about telomeres and telomerase, it can be said that scientists are on the verge of discovering many of telomerase's secrets. In the future, their research in the area of telomerase could uncover valuable information to combat aging, fight cancer, and even improve the quality of medical treatment in other areas such as skin grafts for burn victims, bone marrow transplants, and heart disease. Who knows how far this could go?
Could we extend lifespan by preserving or restoring the length of telomeres with telomerase? If so, would that increase our risk of getting cancer? [Cancer cells unnaturally maintain long telomeres. As previously stated, understanding and controlling telomeres could not only aid in increasing lifespan but in curing cancer as well.]
Scientists are not yet sure. But they have been able to use telomerase in the lab to keep human cells dividing far beyond their normal limit, and the cells do not become cancerous.
If we used telomerase to "immortalize" human cells, we may be able to mass produce cells for transplantation, including insulin-producing cells to cure diabetes, muscle cells for treating muscular dystrophy, cartilage cells for certain kinds of arthritis, and skin cells for healing severe burns and wounds. An unlimited supply of normal human cells grown in the laboratory would also help efforts to test new drugs and gene therapies.