Boston, MA (PRWEB) February 25, 2015
Anyone familiar with the founding principles of Asymmetrex, LLC will appreciate the new editorial from its director and the collection of authors he assembled as Associate Editor for the Frontiers Research Topic, titled “Stem Cell Genetic Fidelity.” Both the introductory editorial and the individual articles are currently available online, ahead of issue in the form of the Frontiers e-book later this year.
Central to the stem cell mechanisms investigated and reviewed by the nine articles is the still controversial proposal of “immortal strands” in adult tissue stem cells. Based on the experimental observations of K. Gordon Lark in the 1960’s, John Cairns predicted the existence of immortal strands of the DNA genetic material about a decade later.
In studies with cultured mouse tissues and plant root tips, Lark had noted that when some cells divided, they seemed to violate well-established genetic laws. These were the Mendelian laws of inheritance, name after Gregor Mendel, who laid their foundation. Each of the 46 human chromosomes has two complementary strands of DNA. One DNA strand is older than the other, because it was used as the template for copying the other. As a result of this inherent age difference in chromosome DNA strands, when the two DNA strands are split to make two new chromosomes – before cell division to produce two new cells – one chromosome in each of the 46 pairs of new chromosomes has the oldest DNA strand.
Mendel’s laws maintain that each new sister cell should randomly get a similar number of chromosomes with the oldest DNA strands. But Cairns hypothesized that adult tissue stem cells had a mechanism to ignore Mendel’s laws. Instead, one of the two cells produced by an asymmetric stem cell division retained all, and only, the chromosomes with the oldest DNA strands. Cairns called these “immortal strands.” By continuously retaining the same complete set of oldest template DNA strands, Cairns envisioned that tissue stem cells could significantly reduce their rate of accumulation of carcinogenic mutations, which primarily occur by chance when DNA is being copied.
Cairns presented his concept of immortal strands in tissue stem cells in a 1975 report to account for a large discrepancy that he had noted between human cancer rates and human cell mutation rates. He estimated that human cancer rates, though still undesirable, fell far short of expectations based on generally known rates of human cell mutation.
Whereas some scientists continue to view Cairns’ immortal strand hypothesis as folly, others consider it genius. In the last decade, progress in evidence for immortal strands in stem cells of diverse animal tissues and animal species accelerated greatly. However, little progress has occurred in defining their role in normal tissue stem cells or diseases like cancer.
In his new editorial, Sherley reveals that he is firmly in the camp that views the immortal strand hypothesis as genius. Before founding Asymmetrex, as a laboratory head in two different independent research institutes – Fox Chase Cancer Center and Boston Biomedical Research Institute – and at the Massachusetts Institute of Technology he developed new tools and approaches for investigating immortal strand functions, which are now a focus for commercial development in the new company. Immortal strands and cellular factors associated with them have significant potential to provide specific biomarkers for tissue stem cells. There is a significant unmet need for such invaluable tools in stem cell research, drug development, and regenerative medicine.
About Asymmetrex (http://asymmetrex.com/)
Asymmetrex, LLC is a Massachusetts life sciences company with a focus on developing technologies to advance stem cell medicine. Asymmetrex’s founder and director, James L. Sherley, M.D., Ph.D. is an internationally recognized expert on the unique properties of adult tissue stem cells. The company’s patent portfolio contains biotechnologies that solve the two main technical problems – production and quantification – that have stood in the way of successful commercialization of human adult tissue stem cells for regenerative medicine and drug development. In addition, the portfolio includes novel technologies for isolating cancer stem cells and producing induced pluripotent stem cells for disease research purposes. Currently, Asymmetrex’s focus is employing its technological advantages to develop facile methods for monitoring adult stem cell number and function in clinically important human tissues.