GASTRIC GOLD'S BLOG

Researchers have identified a protein that plays an important role in the development of stomach cancers and that could one day be a target for new treatments for the disease, according to research published in the British Journal of Cancer.

Scientists based at the Chinese University of Hong Kong explored the role of a protein called RAMP in stomach cancer cell lines and tissues, finding that it is more common in these cells compared to surrounding normal tissues.

The increased presence of RAMP suggests that this protein may play a pivotal role in the multi-step development of stomach cancer. Higher levels of the protein were seen in the very early stages of stomach cancer and were also present throughout the development of the disease. To add further evidence to RAMP's role in this cancer they found that the protein also encouraged cells to grow, fuelling the disease further.


Source
Cancer Research UK
This is the first study to establish a possible link between RAMP and stomach cancer and could help doctors to gain a better understanding of the disease, leading to more effective treatments.

Next the scientists proceeded to 'knock out' RAMP's function in two human gastric cancer cell lines. This slowed down the growth of the cancer in these cell lines and even led to cell death.

It is hoped that these findings could be the first step to developing a new approach to treating stomach cancer by developing treatments that 'switch off' RAMP. This could halt the growth of these tumours and even reduce tumour size.

Study author Dr WK Leung said: "We have established for the first time the role that RAMP plays in stomach cancer. Working out a role for RAMP in stomach cancer gives us more information about the common, but poorly understood steps that lead to the development of this cancer.

"We're very excited about with these results. The next stage of our research will aim to discover more about RAMP's specific role in stomach cancer and begin exploring the possibility of developing new drugs that can stop RAMP in its tracks."

Dr Lesley Walker, director of cancer information at Cancer Research UK, said: "This interesting study helps us understand more about the mechanisms behind the development of stomach cancer. One of the reasons that survival rates for stomach cancers remain low is because they are often at an advanced stage when diagnosed, so making it harder to treat successfully. We welcome new research that could one day help those with stomach cancer face a better prognosis."

In the UK more than 7,700 people are diagnosed with stomach cancer each year, with 95 per cent of cases among the over 50's. Over the last 25 years five-year survival rates have tripled in the UK, but the disease remains very difficult to treat successfully and five year survival is still low at around 15 per cent.

Labels: Cancer, stomach ulcer

New research from Japan found bacteria that cause stomach ulcers and cancer living in the mouths of some people with bad breath, even though they did not show signs of stomach illnesses.

The study was the work of Dr Nao Suzuki from Fukuoka Dental College in Fukuoka, Japan and colleagues and is published in the December issue of the Journal of Medical Microbiology.

Scientists recently discovered that infection by the bacterium Helicobacter pylori, which is carried by over 90 per cent of people in the developing world and 20 to 80 per cent of people in the developed world, was a possible cause of peptic ulcers and gastric cancers.

More recent research has also suggested that the human mouth, which is home to over 600 different species of bacteria (some of which cause disease), is a possible reservoir for H. pylori, particularly in the presence of periodontal or gum disease, a known cause of halitosis or bad breath.

Suzuki explained that bad breath or halitosis is common in humans and is mostly caused by gum disease, tongue debris, poor oral hygiene and badly fitted fillings (they trap bacteria).

"Bacteria produce volatile compounds that smell unpleasant, including hydrogen sulphide, methyl mercaptan and dimethyl sulphide. Doctors often measure the levels of these compounds to diagnose the problem. Gastrointestinal diseases are also generally believed to cause halitosis," said Suzuki.

Suzuki and colleagues decided to investigate the prevalence of H. pylori in the mouths of people with bad breath.

"Recently, scientists discovered that H. pylori can live in the mouth," said Suzuki, adding that:

"We wanted to determine whether the bacteria can cause bad breath, so we tested patients complaining of halitosis for the presence of H. pylori."

For the study, the researchers did DNA scans of saliva taken from 326 Japanese people; 251 had actual bad breath or halitosis and 75 did not. None showed any signs of stomach illnesses.

They found H. pylori and other bacteria that occur with periodontal or gum disease, called periodontopathic bacteria, including Porphyromonas gingivalis, Treponema denticola and Prevotella intermedia.

More spefically the results showed that:

• 21 (6.4 per cent) of the participants had H. pylori in their mouths.


• These participants also had higher levels of other markers for periodontal disease, including higher levels of: methyl mercaptan (a bad breath gas); each of the periodontopathic bacteria; tooth mobility; periodontal pocket depth (PPD); and occult blood in the saliva.


• Of the 102 participants with periodontal disease, 16 (15.7 per cent) had H. pylori in their mouths.

The researchers concluded that the presence of H. pylori in nearly 16 per cent of the participants with periodontitis suggested that:

"Progression of periodontal pocket and inflammation may favour colonization by this species and that H. pylori infection may be indirectly associated with oral pathological halitosis following periodontitis."

"Although the presence of H. pylori in the mouth does not directly cause bad breath, it is associated with periodontal disease, which does cause bad breath," said Suzuki, who said the team will now be looking into the:

"Relationship between H. pylori in the mouth and in the stomach. We hope to discover the role of the mouth in transmitting H. pylori stomach infections in the near future."

"Detection of Helicobacter pylori DNA in the saliva of patients complaining of halitosis."
Nao Suzuki, Masahiro Yoneda, Toru Naito, Tomoyuki Iwamoto, Yousuke Masuo, Kazuhiko Yamada, Kazuhiro Hisama, Ichizo Okada, and Takao Hirofuji.
J. Med. Microbiol, Dec 2008; 57: 1553 - 1559.
DOI: 10.1099/jmm.0.2008/003715-0

Medicalnews

Labels: Cancer, stomach ulcer

Medicalnews

An international team of scientists has discovered that the ubiquitous bacteria that causes most painful stomach ulcers has been present in the human digestive system since modern man migrated from Africa over 60,000 years ago. The research, published online by the journal Nature, not only furthers our understanding of a disease causing bacteria but also offers a new way to study the migration and diversification of early humans.

The international research collaboration was led by scientists from the University of Cambridge, the Max Planck Institute in Berlin, and the Hanover Medical School. The researchers compared DNA sequence patterns of humans and the Helicobacter pylori bacteria now known to cause most stomach ulcers. They found that the genetic differences between human populations that arose as they dispersed from Eastern Africa over thousands of years are mirrored in H. pylori.

Human DNA analysis has shown that along the major land routes out of Africa human populations become genetically isolated - the further from Eastern Africa a population is the more different genetically it is compared to other human populations. Other research has shown gradual differences in European populations, presumed to be the result of Neolithic farmers moving northwards. The international H. pylori research team found almost exactly the same genetic distribution patterns in their results.

The scientists combined their genetic analysis with a computer simulation the modeled the spread of the bacteria across the globe. This showed that it migrated from Eastern Africa at almost exactly the same time as early humans, approximately 60,000 years ago.

The UK research effort was led by Dr Francois Balloux, a Biotechnology and Biological Sciences Research Council-funded scientist at the University of Cambridge. He said: "Humans and this ulcer-causing bacterium have been intimately linked for the last 60,000 years. The research not only shows the likelihood that for tens of thousands of years our ancestors have been suffering the effects of this bacteria but it also opens up new possibilities for understanding early human migration. By showing that Helicobacter pylori emerged from Africa at the same time as early humans it makes it easier to examine some of the controversial questions about human migration. For example we could use our understanding of the bacteria's spread to gauge poorly understood human population shifts in Europe, Africa and Asia."

Labels: stomach ulcer, ulcer