Archive for the ‘Diagnostic’ Category

New method for non-invasive prostate cancer screening

Now a team of researchers led by Shaoxin Li at Guangdong Medical College in China has demonstrated the potential of a new, non-invasive method to screen for prostate cancer, a common type of cancer in men worldwide. They describe their laboratory success testing an existing spectroscopy technique called surface-enhanced Raman scattering (SERS) with a new, sophisticated analysis technique called support vector machine (SVM).

As they described in a new paper in Applied Physics Letters, from AIP Publishing, they combined SERS and SVM and applied them to blood samples collected from 68 healthy volunteers and 93 people who were clinically confirmed to have prostate cancer. They found their technique could identify the cases of cancer with an accuracy of 98.1 percent.

If the technique proves safe and effective in clinical trials, it may become a new method available to patients and their doctors, helping to improve the early detection and diagnosis of this type of cancer, said Li.

“The results demonstrate that label-free serum SERS analysis combined with SVM diagnostic algorithm has great potential for non-invasive prostate cancer screening,” said Li. “Compared to traditional screening methods, this method has the advantages of being non-invasive, highly sensitive and very simple for prostate cancer screening.”

A COMMON CAUSE OF CANCER

According to the World Health Organization, prostate cancer is one of the most common types of cancer in men worldwide and a leading cause of cancer-related death. Every year, there are about 899,000 new cases and 260,000 mortalities, comprising 6 percent of all cancer deaths globally. About 1 in every 6 men will develop prostate cancer over their lifetimes.

While a simple blood test for elevated levels of a protein marker known as prostate specific antigen (PSA) has been used for years to screen for early cases of prostate cancer, the test is far from perfect because the elevated PSA levels can be caused by many things unrelated to cancer. This contributes to over-diagnosis, uncomfortable tissue biopsies and other unnecessary treatment, which can be costly and carry significant side effects. Because of this, the U.S. Preventative Services Task Force now recommends against PSA-based screening for prostate cancer.

According to Li, many scientists have thought about applying SERS to cancer detection because the surface-sensitive type of spectroscopy has been around for years and is sensitive enough to identify key molecules in very low abundance, like pesticide residues on a contaminated surface. This would seem to make it perfect for spotting subtle signals of DNA, proteins or fatty molecules that would mark a case of cancer — exactly why he and his team tackled the problem.

The challenge, he said, was that these changes were, if anything, too subtle. The signal differences between the serum samples taken from the 68 healthy volunteers and the 93 people with prostate cancer were too tiny to detect. So to accurately distinguish between these samples, Li’s group employed a powerful spectral data processing algorithm, support vector machine (SVM), which effectively showed the difference.

While the work is preliminary, it shows that serum SERS spectroscopy combined with SVM diagnostic algorithm has the potential to be a new method for non-invasive prostate cancer screening, Li said. The next research step, he added, is to refine the method and explore whether this method can distinguish cancer staging.

source : http://www.sciencedaily.com/releases/2014/09/140902114041.htm

Carcinogenic role of protein in liver decoded

The EGF Receptor (Epidermal Growth Factor Receptor, EGFR) is a protein which, as a transmembrane receptor, controls a multitude of vital processes in the cell. In human beings, the EGF Receptor is present in many cells types and plays an important role in many types of cancer. It is present in various kinds of tumors in excessive amounts and/or in mutated form, which causes the tumor cells to grow and multiply. For this reason the EGFR serves as a point of attack in many treatment strategies. In the process, its function is inhibited with the objective of slowing down the growth of the tumor cell.

The liver cell carcinoma (hepatocellular carcinoma, short HCC) is one of the most frequent malignant tumors worldwide. Approximately six percent of all cancers in men and about three percent in women are liver cell carcinomas. It is the second most frequent cause of death associated with cancer. Risk factors for HCC include liver diseases through Hepatitis B and C infections as well as alcohol abuse or the classic “fatty liver.”

Up to now, the tumor-promoting role of EGFR has only been linked with its expression directly in the tumor cells. However, the study group of Maria Sibilia, Manager of the Institute for Cancer Research at the Medical University of Vienna and Deputy Manager of the Comprehensive Cancer Centre, in cooperation with the research groups of Michael Trauner and Markus Peck-Radosavljevic at the clinical division for gastroenterology and hepatology (Manager: Michael Trauner) as well as the Eastern Hepatobiliary Surgery Institute/Hospital in Shanghai discovered that EGFR plays a more decisive role in the macrophages of the liver (these are important cells of the immune system which are called Kupffer cells in the liver) with respect to the growth of the liver cell carcinoma than previously assumed.

“In this study we were able to prove that the inhibition of EGFR has a tumor inhibiting effect on the macrophages and not its inhibition on the tumor cell itself,” explains Maria Sibilia. However, if the EGFR conversely exists on these macrophages in an excessive number, it can promote the growth of the tumor. Its existence on the macrophages reduces the chance of survival for HCC patients.

This could explain why EGFR inhibitors utilised for cancer treatment and aiming directly for the tumor cells have achieved clinically disappointing results in the fight against the liver cell carcinoma in the past. For the first time, this study proves the tumor-promoting mechanism for EGFR in non-tumor cells, which could lead to more effective and precise treatment strategies with macrophages as a point of approach in the future.

source : http://www.sciencedaily.com/releases/2014/09/140901090303.htm

Invisible blood in urine may indicate bladder cancer

Scientists at the University of Exeter Medical School found that one in 60 people over the age of 60 who had invisible blood in their urine (identified by their GP testing their urine) transpired to have bladder cancer. The figure was around half those who had visible blood in their urine — the best known indicator of bladder cancer. However, it was still higher than figures for other potential symptoms of bladder cancer that warrant further investigation.

Lead author Sarah Price, a PhD student at the University of Exeter Medical School, led the first robust study to investigate whether invisible blood in urine can indicate bladder cancer. Speaking as the study is published in the British Journal of General Practice on September 1 2014, she said: “It is well known that if you see blood in your urine you should contact your GP, who is likely to refer you for tests. But there is no clear guidance for GPs on what to do if they detect blood that is not visible during routine tests. We are hopeful that our findings will now lead to robust guidance that it warrants further investigation. Early diagnosis is crucial to have the best chance of successfully treating bladder cancer. The three-quarters of patients who are diagnosed early have much better outcomes than those whose disease is diagnosed late. Anything we can do to boost early detection is crucial to help save lives.”

The study examined more than 26,000 people whose anonymized data contributed to the Clinical Practice Research Datalink; this is a large research database used by the Exeter team in several cancer studies. The team found that the risk of bladder cancer was 1.6 per cent in people over 60 who had invisible blood in their urine.

Around 10,000 people in the UK are diagnosed with bladder cancer each year. The condition is more common in men than women and in older people, with the average age of diagnosis at 68. Smoking is among the main causes.

source : http://www.sciencedaily.com/releases/2014/09/140901090731.htm