Telomeres are regions of repetitive sequences of nucleotides (thousands of repeats of TTAGGG sequences on one strand DNA, strand paired with AATCCC on the other strand) that protect the ends of chromosomes, stopping them from deterioration or from fusion with neighboring chromosomes. Their crucial function in the cell biological machinery is therefore to protect our genetic data, while making it possible for the cells to continue dividing.
Telomere length is one of the most critical biomarkers for human aging. In any living organism, aging is the result of the decrease in the number and/or function of cells. Every time cells replicate, which is a highly heterogeneous process influenced not only by genetics but by environmental and, most importantly, life-style factors, telomeres shorten until they reach a point where the cells can no longer divide properly. Cells with such short telomeres usually become senescent, enter apoptosis, and eventually die.
Telomeres play an important role in the aging process and contribute to the onset of age-related diseases.
Telomerase is a reverse transcriptase enzyme that adds new DNA onto the ends of telomeres, elongating telomeres. Without telomerase, present, the chromosome is shortened each time the cell divides. This gene, telomerase, is expressed in the embryo and in stem and germ cells, but it is silenced after birth in most somatic human cells. However, cancer cells manage to reactivate telomerase, thus escaping the mortal fate of adult cells and becoming immortal.
Telomeres and Cancer
Cancer cells have different biological machinery than normal cells. As a cell begins to become cancerous, it divides more often and its telomeres are shortened at a higher rate. Cancerous cells escape senescence/death and conversely, they become immortal with the ability to indefinitely replicate, even with shortened telomeres, resulting in uncontrolled tumor growth. It has been demonstrated that this ability to escape the natural cell outcome happens because cancer cells prevent telomeres from becoming critically short by the reactivation of telomerase (phenomenon occurring in 85% of cancers) or by ALT (alternative lengthening of telomeres; 15%). Telomerase is therefore responsible for proliferation and survival of malignant cells.
Life Length’s Telomere Analysis Technologies are the most valuable, versatile and scalable technologies in the market for telomere diagnosis. While some companies offer mean telomere length analyses, Life Length is the only company in the world able to measure short telomeres in individual cells, which is the relevant indicator of telomere dysfunction and cellular aging.
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