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Archive - Mar 27, 2015

Hopkins Study Suggests Non-Dye-Based MRI Analysis of Cell-Surface Sugar Molecules Can Differentiate Cancer and Non-Cancer Cells

Imaging tests like mammograms or CT scans can detect tumors, but figuring out whether a growth is or isn't cancer usually requires a biopsy to study cells directly. Now results of a Johns Hopkins study suggest that MRI could one day make biopsies more effective or even replace them altogether by noninvasively detecting telltale sugar molecules shed by the outer membranes of cancerous cells. The MRI technique, so far tested only in test-tube-grown cells and mice, is described in a report published online on March 27, 2015 in an open-access article in Nature Communications. The article is titled “Label-Free in vivo Molecular Imaging of Underglycosylated Mucin-1 Expression in Tumor Cells.” "We think this is the first time scientists have found a use in imaging cellular slime," says Jeff Bulte, Ph.D., a Professor of Radiology and Radiological Science in the Institute for Cell Engineering at the Johns Hopkins University School of Medicine. "As cells become cancerous, some proteins on their outer membranes shed sugar molecules and become less slimy, perhaps because they're crowded closer together. If we tune the MRI to detect sugars attached to a particular protein, we can see the difference between normal and cancerous cells." Dr. Bulte's research builds on recent findings by others that indicate glucose can be detected by a fine-tuned MRI technique based on the unique way it interacts with surrounding water molecules without administering dyes. Other researchers have used MRI, but needed injectable dyes to image proteins on the outside of cells that lost their sugar. In this study, Dr. Bulte's research team compared MRI readings from proteins known as mucins, with and without sugars attached, to see how the signal changed.

New Immune-System-Based Biomarker Set from Europe May Be Used in Blood Test for Early Detection of Colon Cancer

Colorectal cancer is the third most common form of cancer globally and the second most common cause of cancer deaths. The chance of a cure is high if the cancer is detected early enough, but early detection is not a given. Researchers from VIB and KU Leuven - together with various European oncology centers, including UZ Leuven - have identified bio-markers that can be incorporated in a new diagnostic test. This should make it possible to detect colorectal cancer at an early stage using a simple blood test. The results were published online on March xx, 2015 in Gut in an article titled “Tumour-Educated Circulating Monocytes Are Powerful Candidate Biomarkers for Diagnosis and Disease Follow-Up of Colorectal Cancer.” Dr. Max Mazzone (VIB/KU Leuven) commented: “This research demonstrates how important it is to gain a thorough understanding of the role of our immune system in cancer. In this case, this knowledge will hopefully result in a new, more sensitive test to detect colorectal cancer at an early stage, so that more patients can be cured. I hope that we can soon find an industrial partner to help us achieve the following step, which is the development of the test.” In 2012, a total of 1.4 million people worldwide were diagnosed with colorectal cancer, this figure is expected to increase to 2.4 million by 2035. This is a condition that affects a growing number of people each year. Colorectal cancer is very treatable if it is detected at an early stage, with approximately 95% chance of a cure. If detected at a late stage, however, the chance of surviving 5 years after diagnosis is less than 10 %. Therefore, it is very important to be able to detect the disease in an early stage. And therein lies the rub.

Differently Colored Lettuces Have Antioxidants That Act at Different Speeds

Lettuce, one of the indispensable vegetables in the Mediterranean diet, is a food that greatly benefits health, mainly because it is rich in antioxidants. But not all lettuce varieties have the same antioxidant effect. According to a study led by the researcher Dr. Usue Pérez-López of the Department of Plant Biology and Ecology of the UPV/EHU's Faculty of Science and Technology (Universidad del Pais Vasco/Euskal Herriko Unibertsitatea or University of the Basque Country), the color of the leaves of these vegetables is an indicator of the speed at which their antioxidants act. So Lettuces with green leaves have antioxidants that react more slowly, while red-leaf lettuces have a faster effect. The results of this study have been set out in a paper titled "Phenolic Composition and Related Antioxidant Properties in Differently Colored Lettuces: A Study by Electron Paramagnetic Resonance (EPR) Kinetics" published online on November 11, 2014 in the Journal of Agricultural and Food Chemistry. Antioxidants provide long-term protection against the chain reactions of free radical processes, in other words, of the electron-charged highly reactive oxidizing molecules that are capable of causing cell damage and generating various diseases. Lettuce is rich in antioxidants, as it contains compounds like phenolic acids, flavonoids, anthocyanins, and vitamins A and C, among other antioxidants. To conduct this research, which began in 2011 and in which researchers of the UPV/EHU and the University of Pisa (Italy) have been participating, the compounds of three lettuce varieties were analyzed: the green-leaf “Batavia,” the semi-red-leaf “Marvel of Four Seasons,” and the red-leaf “Oak Leaf” (photo).

Gene Duplication Played Key Role in Evolution of Vertebrate Eye

A new study from SciLifeLab at Uppsala University in Sweden shows that genes crucial for vision were multiplied in the early stages of vertebrate evolution and acquired distinct functions leading to the sophisticated mechanisms of vertebrate eyes. One striking feature of vertebrates is the prominent role that vision plays in almost all major animal groups. The vertebrate eye has a unique organization and is known to have arisen at the time of the first vertebrates over 500 million years ago. A new study by the research team led by Dr. Xesús Abalo and Dr. Dan Larhammar explains how ancient gene duplications have played decisive roles in the evolution of novel functions. The first step in vision is the response to light by the cone and rod cells in the retina at the back of the eye. Twenty years ago, the first studies of the light receptors, proteins called opsins, in birds indicated that color vision arose before the dim light black-and-white vision provided by rods. This hypothesis was recently confirmed by detailed studies of opsin genes in a broad range of vertebrate species (David Lagman and Daniel Ocampo Daza in the team of Abalo & Larhammar, open-access, http://www.biomedcentral.com/1471-2148/13/238). The authors found that new opsin genes were generated when the genome of the vertebrate ancestor was doubled twice at the dawn of the vertebrates. These massive gene duplication events resulted in many novel functions, not only for vision, but also for many other characteristic vertebrate features. In the new study, Dr. Lagman and co-workers describe evolutionary changes in the first relay step in the vision cascade, mediated by a family of G-proteins called transducins. These trigger the cellular response by activating a critical enzyme.