How To Capture Quickly Cancer Markers

A nanoscale product of human cells that was once considered junk is now known to play an important role in intercellular communication and in many disease processes, including cancer metastasis. Researchers at Penn State have developed nanoprobes to rapidly isolate these rare markers, called extracellular vesicles (EVs), for potential development of precision cancer diagnoses and personalized anticancer treatments.

Lipid nanoprobes

Most cells generate and secrete extracellular vesicles,” says Siyang Zheng, associate professor of biomedical engineering and electrical engineering. “But they are difficult for us to study. They are sub-micrometer particles, so we really need an electron microscope to see them. There are many technical challenges in the isolation of nanoscale EVs that we are trying to overcome for point-of-care cancer diagnostics.”

At one time, researchers believed that EVs were little more than garbage bags that were tossed out by cells. More recently, they have come to understand that these tiny fat-enclosed sacks — lipids — contain double-stranded DNA, RNA and proteins that are responsible for communicating between cells and can carry markers for their origin cells, including tumor cells. In the case of cancer, at least one function for EVs is to prepare distant tissue for metastasis.

The team’s initial challenge was to develop a method to isolate and purify EVs in blood samples that contain multiple other components. The use of liquid biopsy, or blood testing, for cancer diagnosis is a recent development that offers benefits over traditional biopsy, which requires removing a tumor or sticking a needle into a tumor to extract cancer cells. For lung cancer or brain cancers, such invasive techniques are difficult, expensive and can be painful.

Noninvasive techniques such as liquid biopsy are preferable for not only detection and discovery, but also for monitoring treatment,” explains Chandra Belani, professor of medicine and deputy director of the Cancer Institute,Penn State College of Medicine, and clinical collaborator on the study.

We invented a system of two micro/nano materials,” adds Zheng. “One is a labeling probe with two lipid tails that spontaneously insert into the lipid surface of the extracellular vesicle. At the other end of the probe we have a biotin molecule that will be recognized by an avidin molecule we have attached to a magnetic bead.”

Source: http://news.psu.edu/

New Technique Identifies Cancer In Urine Or Blood

A team of researchers, led by Professor Yoon-Kyoung Cho of Life Science at UNIST  (South Korea) has recently developed a new technique that effectively identifies cancer-causing substances in the urine or blood.

In the study, Professor Yoon-Kyoung Cho of Life Science, a group leader at IBS Research Center for Soft and Living Matter (CSLM) presented an integrated centrifugal microfluidic platform (Exodisc), a device that isolates extracellular vesicles (EVs) from urine.  The research team expects that this may be potentially useful in clinical settings to test urinary EV-based biomarkers for cancer diagnostics.

Extracellular vesicles (EVs) are cell-derived nanovesicles (40-1000 nm in size), present in almost all types of body fluids, which play a vital role in intercellular communication and are involved in the transport of biological signals for regulating diverse cellular functions. Despite the increasing clinical importance of EVs as potential biomarkers in the diagnosis and prognosis of various diseases, current methods of EV isolation and analysis suffer from complicated procedures with long processing times. For instance, even ultracentrifugation (UC), the most commonly used method for EV isolation, requires time-consuming steps involving centrifugation and acquisition of large sample volumes, and the results suffer from low yield and purity.

To overcome these limitations, Professor Cho presented a new lab-on-a-disc platform for rapid, size-selective, and efficient isolation and analysis of nanoscale EVs from raw biological samples, such as cell-culture supernatant (CCS) or cancer-patient urine.

EXODISC

The Exodisc is compoased of two independent filteration units (20nm and 600nm in size) within a disk-shaped chip to enable the processing of two different samples simulateously,” says Hyun-Kyung Woo (Combined M.S./Ph.D. student of Natural Science), the first author of the study. “Upon spinning the disc, the urine sample is transferred through two integrated nanofilters, allowing for the enrichment of unirary EVs within the size range of 20 to 600 nm.”
Using Exodisc, it is possible to isolate EVs from raw samples within 30 minutes,” says Professor Cho. “The process of passing the filter through centrifugal force is automatically carried out, effectively recovering the enriched EVs.”

On-disc ELISA using urinary EVs isolated from bladder cancer patients showed high levels of CD9 and CD81 expression, suggesting that this method may be potentially useful in clinical settings to test urinary EV-based biomarkers for cancer diagnostics,” explains Vijaya Sunkara of Life Sciences, the co-first author.
The results of the study has been published in the February issue of ACS Nano journal.

Source: http://news.unist.ac.kr/

Breath Test To Detect Early Signs Of Lung Cancer

A simple breath test could soon help doctors detect the early signs of lung cancer. The sensor inside this breathalyser measures minute chemical traces in a patients’ exhaled breath which could be a biomarker for cancer.

breathalyzer2CLICK ON THE IMAGE TO ENJOY THE VIDEO

The challenge is most people present when it’s very late stage, and it’s about managing symptoms as opposed to curing them. So the key thing that you can do is detect the disease early; and that’s what we think the breathalyser technology allows for, picking it up at that earliest stage when it’s treatable“, says Billy Boyle, CEO of the Brtish company Owlstone Medical.

Breath testing is already a recognised method for linking specfiic chemicals present in exhaled breath to existing medical conditions, but current technology is often expensive, slow and complex to use. Owlstone Medical believe they have the answer.

Historically chemical analysers take up half the size of a room and cost half a million dollars. So what we’ve been able to do is use microchip technology to shrink it down from these massive devices to something about the size of a button. And once it’s in that form factor, you can build it directly into these disease breathalyser technologies“, adds Billy Boyle.

Known as volatile organic compounds, the chemical markers of lung cancer are present even in the earliest stage of the disease.

And this device can collect those samples, those tiny amounts of volatile organic compounds, which we can then analyse in the laboratory. And in effect, it’s a bit like a fingerprint. If you have a lung cancer we believe that we can detect these samples and that fingerprint will tell us whether the person has lung cancer or not“, comments Dr. Robert Rintoul, consultant ‘Respratory Physician’ at Papworth Hospital.

Clinical trials involving up to 3,000 volunteer patients are underway at 17 British hospitals, with the aim of having the non-invasive technology in GP’s surgeries in 2017. In Britain alone there are about 45,000 new cases of lung cancer each year. Owlstone believes it’s technology could potentially save 10,000 lives a year by helping to spot the disease before it takes hold.

Source: http://www.owlstonenanotech.com/

How To Detect Alzheimer’s Years Before Memory Loss

Chilean neurologists say they’ve found a key to diagnosing Alzheimer’s disease early, even before memory loss and other symptoms develop. Researchers at Chile’s Biomedical Neuroscience Institute (BNI) believe they can identify early stages of dementia and other psychiatric diseases in sufferers through observing eye movement patterns and the brain’s electrical activity. The neurologists study patients navigating a virtual location, where they must find “keys” to complete a task. Lead neurologist Enzo Brunetti said the tests were able to detect very early signs of cognitive impairment in patients who apparently presented no symptoms of Alzheimer’s.

Eye movement link to Alzheimer's

Eye movements and brain activity may be the key to diagnosing Alzheimer’s disease earlier and more accurately, according to research led by Chilean neurologists.
CLICK ON THE IMAGE TO ENJOY THE VIDEO

In this study, what we did was that we applied spatial navigation tasks using a computer, and with the help of a software we examined in detail which were the early functions that became altered in Alzheimer’s disease (patients) and focused on a very specific function, linked to the codification and development of cognitive memory, that helps people move through the physical environment. This is one of the cognitive functions that were altered in patients with Alzheimer’s and we observed that they were altered from very early stages. Therefore we believe this is a biomarker for the disease, which would give us an opportunity to shed light on an early diagnosis for this disease“, says Enzo Brunetti, neurologist.
Brunetti says the patients who are likely to develop some form of dementia make similar eye movements while navigating through the virtualroom” to those at a developed stage of the disease. With the help of electrodes that measure the brain’s electrical activity, the neurologists run non-invasive electroencephalogram (EEG) tests on patients while they navigate through the computer-made universe.
More tests and a larger clinical trial are needed before the treatment can be made available. An early Alzheimer’s diagnosis may not only help patients and their families plan better for the future, but also offer them a possibility of delaying the symptoms with drugs and other existing treatments. Alzheimer’s is very difficult to detect until it has progressed from mild memory loss to clear impairment. Patients eventually lose all ability to care for themselves.

Source: https://www.washingtonpost.com/