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Sunday, July 8, 2012

Cancer scientists link ‘oncometabolite’ to onset of acute myeloid leukemia




In this study, cancer scientists discovered a causative link between the product of a mutated metabolic enzyme and the onset of acute myeloid leukemia (AML), one of the most common types of leukemia in adults.

A team of international scientists led by principal investigator Dr. Tak Mak at the Princess Margaret Cancer Centre, University Health Network, has identified a causative link between the product of a mutated metabolic enzyme and the onset of acute myeloid leukemia (AML), one of the most common types of leukemia in adults.
Called an “oncometabolite” for its role in cancer metabolism, the metabolite2-hydroxyglutarate (2HG) is a by-product of a gene mutation of an enzyme known as isocitrate dehydrogenase (IDH).
Says Dr. Tak Mak of the findings published today in Nature: “For the first time, we have demonstrated how a metabolite can cause cancer. This sets the stage for developing inhibitors to block the mutation and prevent the production of this disease-initiating enzyme.” The research team included scientists at Weill Cornell Medical College, New York City, and Agios Pharmaceuticals, Cambridge, Massachusetts.
Dr. Mak, Director, The Campbell Family Institute for Breast Cancer Research at Princess Margaret Hospital, is an internationally acclaimed immunologist renowned for his 1984 discovery of cloning the human T-cell receptor. He is also Professor, University of Toronto, in the Departments of Medical Biophysics and Immunology.
Cancer scientists link ‘oncometabolite’ to onset of acute myeloid leukemia
Blood cell development. A blood stem cell goes through several steps to become a red blood cell, platelet, or white blood cell.
Adult acute myeloid leukemia (AML) is a cancer of the blood and bone marrow. AML is also called acute myelogenous leukemia, acute myeloblastic leukemia, acute granulocytic leukemia, and acute nonlymphocytic leukemia.
The connection between cancer and metabolism has fascinated scientists at Agios and Dr. Mak, who were the first to identify the oncometabolite in research published in Nature (2009) and The Journal of Experimental Medicine (2010). The IDH gene mutation was initially discovered in brain cancers in 2008 by American scientists at Johns Hopkins in Baltimore and subsequently also linked to leukemia.
In the lab, Dr. Mak’s team genetically engineered a mouse model with the mutation in its blood system to mimic human AML. They discovered that the gene mutation launches the perfect storm for the oncometabolite to trigger the blood system to increase the stem cells pool and reduce mature blood cells in the bone marrow. The resulting condition creates a situation with similarities to myelodysplastic syndrome – one of the precursors to this type of leukemia.
“This is one of the most common mutations in AML,” says Dr. Mak. “We also found that it is the common mutation in about 40% of a specific type of lymphoma.” The mutation is also known to be involved in about 70-90% of low-grade brain cancers (glioblastomas gliomas) and a variety of other cancers.
Dr. Mak’s interest in the blood system began as a young researcher three decades ago with Drs. Ernest McCulloch and James Till, the acclaimed “fathers of stem cell science” at Ontario Cancer Institute, the research arm of Princess Margaret Hospital, whose 1961 discovery of stem cells launched the new field.
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Dr. Mak’s research was funded by grants from the Canadian Institutes of Health Research, the Ontario Ministry of Health and Long-Term Care and the Terry Fox Foundation. Dr. Mak’s research is also supported by The Princess Margaret Hospital Foundation. 

HEALTH TIPS WITH PICTURES











Beautiful photos of Mont Saint Michel Castle, France





Mont Saint-Michel (English: Mount Saint Michael) is a rocky tidal island in Normandi, about one kilometer from the coast of northern France at the mouth of the river Couesnon near Avranches. Residents of Mont Saint-Michel called Montois.
Mont Saint-Michel was originally connected to the mainland via a thin natural land bridge, and then before the modernization covered at high tide and visible at low tide. Therefore, the Mont Saint Michel holds a mystique of island pairs. In 1879, the land bridge was built into a causeway.
Before construction of the first monastic in the 8th century, the island was called Mont Tombe. According to legend, the Archangel Michael appeared to St.. Aubert, Bishop of Avranches, in 708 and ordered him to build a church on the island. Aubert ignore the instruction many times, until Michael makes a hole in the bishop’s skull with his finger.
In 1067, the abbey of Mont Saint-Michel William Normandi support that claim the British throne. The abbey was granted land in the UK, including a small island in the west Cornwall, which mimics the style of Mount Saint-Michel and is called St. Michael’s Mount in Penzance.
                                                                                              Le Mont-Saint-Michel, rocky, cone-shaped islet in  northwestern France, in the Gulf of Saint-Malo, connected by a causeway with the mainland. The islet, celebrated for its Benedictine abbey, has small houses and shops on its lowest level. Above these stand the monastic buildings, many of which date from the 13th century and are considered outstanding examples of Gothic architecture. The entire islet is crowned by the abbey church, about 73 m (about 240 ft) above sea level.  


The first chapel on this site was founded in 708 by Aubert, Bishop of Avranches , after the Archangel Michael has appeared to him in a dream. The Archangel Michel appeared here in the year 708. The Abbey takes the name of Mont saint Michel. The oratory, consecrated in 709 was served by a community of canons. It apparently survived the Norman invasions, but the observance of the rule became very relaxed. In 966 Richard I, Duke of Normandy, established there the Benedictine monks from St. Wandrille Abbeyunder the direction of Abbot Maynard, who began the reconstructions of the church and other buildings. The church was burnt in 922 and rebuilt on a larger scale by Abbot Hildebert II from 1023, at the time of the monastic reforms in Normandy carried out by Richard II and William of Volpiano


During the Hundred years War the fortifications of Mont St. Michel were reinforced (1420) and the Romanesque choir collapsed Construction of the present clever began in 1448. In 1622 the abbey became part of the Congregation of St. Maur; three western nave bays and the facade were destroyed and replaced with large terrace. The abbey was dissolved at the Revolution (1789-95), and it was used as a prison in the 19th. century. It was severely burnt in 1856, but thorough restorations were not undertaken until 1874.

The buildings of Mont St. Michel are constructed of granite, but there is some limestone in the cloister. 
The village that grew up and around the abbey lies huddled within the fortifications and includes a Romanesque parish church, remolded in the 15 century. The fortifications include crenellated ramparts, towers and a 14th century barbican, which reinforce the abbey's own defenses. The tower Claudine protects the monastery entrance.

Mont Saint Michel was built as a medieval castle.  It has two large towers to defend the entrance to the castle.
St. Michael is a surety for freedom and thus this sanctuary also became a symbol of the allied landing in Normandy during the Second World War.

POEM WRITTEN BY ONE OF OUR TOUR PARTICIPANTS IN JUNE 2001.














Mt. St.Michael
It rises up in the deceiving distance
Like a beacon to the wretched and weak
As the lighthouse at Alexandria once opened the seas
To weary travelers, drunk on sea salt and night.
The waves crash on its forgotton stones
Slowly washing away one thousand years
But Mount St. Michael is eternal.
The spirits in the catacombs sleep silent
Remembered in the chants on the monks.
As the ghostly brothers wander the halls
Drinking secrets from the ancient chalice
And tending the grapes for their moonshine wine.
So sacred a place, the stairs need guard it,
Winding in dozens up steep narrow passages
Up and up to the nearing warm skies
Til you reach a breezy gothic chapel
So high you can hear the prayers in the walls
And echoing in the lulling lowly waves
Tamed and bowing seemingly a mile beneath.
Is it a house of God or a fortress of war?
Candlelight of hope or dimness of despair?
No matter, for the people still come
The devoted, the curious and above all the lost
Searching for answers in the carvings,
A lost soul within the tombs
Or inner peace through the stained glass windows of time.

~Robyn Schwartz~ (10/23/01)