IRB Barcelona has identified GEMC1 as a master gene for the generation of multiciliated cells—cells with fine filaments that move fluids and substances—which are found exclusively in the brain, respiratory tract, and reproductive system.

Defects in multiciliated cells lead to ciliopathies—rare and complex diseases that are poorly understood and for which not all causative genes have been identified.

The genomic sequencing of hundreds of patients with diverse types of ciliopathies has revealed that “in many cases the gene responsible is not known”, says Travis Stracker, head of the Genomic Instability and Cancer Lab at the IRB Barcelona. “So many people do not have a molecular diagnosis,” stresses the researcher. “Our work seeks to contribute to bridging this knowledge gap”.

A study on mice by Travis Stracker and his team, in collaboration with Vincenzo Costanzo’s laboratory at the FIRC Institute of Molecular Oncology (IFOM) in Milan, in which they reveal a gene candidate for a subtype of human ciliopathy. The gene in question, GEMC1, is indispensable for the generation of multiciliated cells specific to tissues such as the brain, trachea, lungs and oviducts.

The surface of multiciliated cells is covered by hundreds of cilia. These tiny, hairlike structures serve to circulate cerebrospinal fluid, remove mucus from the respiratory tract, and transport ovum through the oviduct, among other functions. Defects in the generation or function of these cells causes a subtype of ciliopathies called Mucociliary Clearance Disorders.

Specifically, GEMC1-deficient mice produced by Stracker reproduce the symptoms of a rare disease called RGMC (Reduced Generation of Multiple Motile Cilia)—a condition that causes hydrocephaly, severe respiratory infections, and infertility. The work, led by IRB Barcelona PhD student Berta Terré and IFOM postdoctoral researcher Gabriele Piergiovanni, reports that GEMC1 regulates the only two genes known to date that underlie this disease, Multicilin and Cyclin O, thus making it a potential candidate gene for RGMC.

In addition, the study has revealed that GEMC1 is one of the most important genes in the gene signalling cascade for the production of multiciliated cells. This means that this gene affects many others that depend on its expression. The gene expression analysis of this first study has revealed at least 10 new candidate genes related to cilia, as well as dozens that were already known or suspected of being involved in the function of cilia. IRB Barcelona

An international team that includes researchers at Sahlgrenska Academy has found a new genetic cause of osteoporosis. The findings set the stage for eventually curing the disease.

Osteoporosis is a common condition that leads to fractures with half of all women experiencing a fracture during their lifetime.

The discovery of a genetic variant has permitted researchers to link a particular gene to bone density and fractures. Follow-up studies have described the mechanisms by which the protein coded by the gene affects bone density.

Sahlgrenska Academy Professor Claes Ohlsson, who participated in the study, says, “Given that the EN1 gene has never been associated with osteoporosis before, we have a brand new pathway for developing drugs that can inhibit the condition.”

Directed by Canadian scientists, the international study initially examined highly detailed genetic data from 10,000 individuals and subsequently replicated the EN1 discovery in 500,000 others. The inclusion of so many subjects allowed the researchers to establish correlations between rare genetic changes and pathological conditions.

 “The study is clear evidence that uncommon genetic variants can have a significant impact on widespread diseases,” Professor Ohlsson says. “We have discovered a new mechanism for regulating bone density and fractures.” Sahlgrenska Academy, University of Gothenburg

A team of scientists at the Helmholtz Zentrum München together with colleagues of the Ludwig Maximilians University Munich recently developed a new strategy to determine monocyte subsets involved in diseases. The results could help facilitating the diagnosis of sarcoidosis and may improve the respective patient management.

Monocytes are white blood cells that are crucial to human immune defence.  They are precursor cells of macrophages and dendritic cells and are circulating in the blood until they invade their respective target tissue where they defend the body against exogenous structures. So far, scientist categorized subtypes of monocytes only with regards to the surface markers CD14 and CD16* – however, this might change in the future.

In the current study, the team headed by Prof. Loems Ziegler-Heitbrock was able to show that the analysis of an additional marker molecule called slan allows a more precise determination of monocyte subgroups. The results of the researchers show that this classification might also lead to a better understanding of certain diseases.

To this end Dr. Thomas Hofer and Dr. Marion Frankenberger, scientists of the Comprehensive Pneumology Center (CPC) at Helmholtz Zentrum München, analysed blood samples of patients suffering from sarcoidosis. This disease, which often leads to damage of the patients’ lungs, is caused by a strong immune reaction and a concomitant formation of nodules in the tissue. The underlying mechanisms are still unclear but scientists are convinced that monocytes play a critical role. “Our data clearly indicate which subtype of the monocytes is involved in the disease”, explains Hofer. “In the patients’ blood we found significant numbers of monocytes, which were positive for CD16 and negative for slan.” According to Hofer, these cells might play a major role in sarcoidosis.

Moreover, in further experiments the scientist found that the marker slan might also serve to gain insights into a brain disease: “To test the predictive value of our new diagnostic tool, we also analysed samples of patients suffering from HDLS, a disease which leads to destruction of neurons of the brain”, said Frankenberger. “Our results show that a clearly definable subgroup of monocytes (CD16 positive/slan positive) was almost absent in the blood of these patients. Therefore we presume that these cells are important for normal brain function”, explains the Co-author.

“With this novel approach we now have a new diagnostic tool and we expect this to have an impact in many areas of medicine”, concludes principle investigator Ziegler-Heitbrock. “In the future we are planning to investigate whether slan might also lead to new insights with regards to other diseases.” The Helmholtz Zentrum München

A new study provides insight on the potential role played by RNA (ribonucleic acid) editing in cancer.

The findings may further our understanding of an emerging mechanism implicated in tumour initiation and progression, and may thus lead to the development of better treatment options in the future.

In every healthy human cell, the genetic information hard-wired into the DNA is transcribed into messenger RNA, which is in turn translated into proteins, the workhorses of all body tissues and organs. The prevailing view is that most malignancies are caused by DNA mutations, which can lead to the aberrant activation or inactivation of the corresponding protein products and to the consequent out-of-control growth and proliferation of malignant cells. RNA editing, the process by which ‘mutations’ of the RNA sequence are introduced post-transcriptionally, has the potential to impact a variety of cellular processes yet the precise mechanism of how has been poorly understood until now.

Previous studies have shown that more than one million sites in the genome are edited to various degrees. Despite the fact that a majority of these editing sites fall within regions that are not translated to protein, it has been shown that the differences in RNA editing levels between tumour and normal tissues are associated with different clinical outcomes. Currently, only a few coding RNA editing sites have been functionally characterized. However, it is still a puzzle whether and how the majority of the RNA editing events in the un-translated regions affect tumour growth.

Researchers from Boston University School of Medicine (BUSM) analysed 14 tumour types, and identified more than 2,000 genes showing significant changes in RNA editing level between tumour and normal tissues.

“This study suggests that RNA editing may serve as an important epigenetic mechanism of cellular regulation beyond the genetic/DNA level,” explained corresponding author Stefano Monti, PhD, associate professor of medicine at BUSM. “We show that the effect of one epigenetic component can be offset by changes in another epigenetic component. Thus, it is important to have a comprehensive picture of changes in the cancer genome, which may point to vulnerabilities amenable to targeted treatment,” added lead author Liye Zhang, PhD, postdoctoral fellow at BUSM. Boston University School of Medicine

Rheonix Inc., a developer of fully automated molecular diagnostics solutions, has been granted patent 9,132,398, “Integrated Microfluidic Device and Methods,” for the Rheonix CARD^® cartridge, which enables assays to be performed on the company’s EncompassMDx^® and Encompass Optimum™ instruments. The CARD, which stands for Chemistry and Reagent Device, will make molecular diagnostics simpler and easier to perform through an innovative and functional design that delivers a fully automated molecular assay at a fraction of the cost of other options. All assay steps are performed within the fully enclosed cartridge, thus eliminating the potential for contamination, reducing user error, and streamlining workflow.
The CARD’s design enables adoption of advanced molecular technology by laboratories of all types, from small community hospital labs to highly complex, centralized laboratories. The design also facilitates implementation across a wide range of market opportunities, including next-generation sequencing (NGS) sample prep, research-use-only testing, food and beverage industry applications, and in vitro diagnostics.  
The ’398 patent allows researchers and clinicians to quickly, easily, and cost-effectively run several samples through a fully integrated and automated nucleic acid amplification test, from raw sample input through detection, with no user intervention. Each CARD allows for simultaneous testing of four different samples and can handle a broad range of sample types, such as fresh tissue, urine, whole blood, serum, saliva, swabs, and formalin-fixed, paraffin-embedded (FFPE) tissue. The Rheonix CARD performs multiple molecular techniques, including sample preparation, such as chemical and enzymatic lysis and DNA purification; amplification, such as endpoint polymerase chain reaction (PCR), reverse transcriptase PCR, and quantitative PCR; and detection on a low-density microarray or lateral flow strip.
“The ’398 patent recognizes the groundbreaking achievement we have reached with the Rheonix CARD. From the device’s hardware to its process, it will help make molecular diagnostics a reality in laboratories worldwide,” said Tony Eisenhut, president of Rheonix. “With the lowest cost of ownership of any molecular platform, the patent confirms the novelty of the Rheonix approach to molecular diagnostics. Where other systems have traditionally emphasized either multiplex or throughput, Rheonix has designed single-use cartridges that do both and can perform sophisticated functions with a simple design. This lowers laboratory costs by eliminating waste in time, equipment and consumables, and reduces the amount of highly skilled labour. Rheonix is helping bring powerful molecular tools to laboratories that could not previously afford to purchase or run them.”
The dual-layer design of the Rheonix CARD automatically manipulates reagents internally with its active fluidic network of pumps, valves and channels. The upper surface of the CARD contains reservoirs that hold reagents used in the extraction, purification, amplification and detection process and any resulting liquid waste. The channels and pumps located on the lower surface of the CARD are used to transport and mix reagents and move wastes into the reservoirs on the top. By actively pumping fluids from reservoir to reservoir within the CARD, molecular diagnostic tests can be performed automatically.

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