Researchers at the University of Southern California (USC) recently made significant strides toward settling a decades-old debate centering on the role played by stem cells in cancer development. According to the study's findings, which appear in an upcoming issue of Nature Genetics and now available online, genes that are reversibly repressed in embryonic stem cells are over-represented among genes that are permanently silenced in cancers; this link lends support to the increasingly discussed theory that cancer is rooted in small populations of stem cells.
USC researchers uncovered this link after observing that of 177 genes repressed by Polycomb group (PcG) proteins, fully 77 showed evidence of cancer-associated enzymatic modification of DNA (known as methylation). "Finding that a Polycomb target in an embryonic stem cell is 12 times more likely to become abnormally methylated in cancer is highly significant," says Peter Laird, Ph.D., one of the lead researchers and associate professor of surgery, biochemistry and molecular biology, and director of basic research for surgery at the Keck School of Medicine of USC.
Laird and his colleagues discovered that some genes repressed by Polycomb in embryonic stem cells are essentially pre-marked to become permanently silenced by DNA methylation. "This permanent silencing," Laird explains, "prevents embryonic stem cells from differentiating, and they thus become the seeds of cancer development later in life." USC researchers made these observations in relation to breast, colorectal, lung, and ovarian cancer.
Not only does the USC study provide empirical evidence for a stem cell origin of cancer, but, according to Laird, "It also supports a very early involvement of epigenetics in cancer. We found that cancer arises in cells that have already undergone epigenetic alterations," he adds, "which points to epigenetic events preceding genetic events in cancer development." Laird notes that this theory, while relatively new, is gaining support among scientists.
Findings from the USC study also can be applied to stem cell research funded by the California Institute for Regenerative Medicine (CIRM), which was created through passage of California Proposition 71 in 2004. "One of CIRM's aims," says Laird, "is to culture and differentiate embryonic stems cells – cells that would then be placed into patients. Since our research shows that cancer is rooted in stem cells, it would be very important to screen for the epigenetic abnormalities that we uncovered, so as to prevent people from receiving potentially cancer-prone cells."
Looking ahead, Laird and his USC colleagues would next like to focus on what causes some genes to transition from temporary repression to permanent silencing. "Once we determine that," Laird explains, "we can turn to the fundamental question: How can we prevent this transition?"
Jennifer Chan | EurekAlert!
Zebrafish's near 360 degree UV-vision knocks stripes off Google Street View
22.06.2018 | University of Sussex
New cellular pathway helps explain how inflammation leads to artery disease
22.06.2018 | Cedars-Sinai Medical Center
In a recent publication in the renowned journal Optica, scientists of Leibniz-Institute of Photonic Technology (Leibniz IPHT) in Jena showed that they can accurately control the optical properties of liquid-core fiber lasers and therefore their spectral band width by temperature and pressure tuning.
Already last year, the researchers provided experimental proof of a new dynamic of hybrid solitons– temporally and spectrally stationary light waves resulting...
Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...
Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.
Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...
The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.
Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.
An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.
Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...
13.06.2018 | Event News
08.06.2018 | Event News
05.06.2018 | Event News
22.06.2018 | Materials Sciences
22.06.2018 | Earth Sciences
22.06.2018 | Life Sciences