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Thursday, June 30, 2011

Platinum

Characteristics

Commodity
Platinum is considered as one of the most precious metals. In nature it is generally found as part of the so-called Platinum Group Metals (PGMs) and together with other metals such as gold, nickel or copper. The PGMs are Platinum (Pt), Palladium (Pd), Rhodium (Rh), Ruthenium (Ru), Iridium (Ir) and Osmium (Os). Platinum and Palladium are the most important of the PGMs.
Platinum is a rare, scarce and costly metal and it shows certain properties which make it unique. The specific chemical and physical properties of this metal are of essential use for many different applications. Platinum is known as the environmental metal. As a matter of fact, approximately 20% of the goods manufactured in the world contain platinum or are produced using platinum.

Origin and history
Although platinum is regarded as a "new" metal in its present form, it has a long history. Ancient Egyptians and Pre-Columbian Indian civilizations already valued it as a very important element. The "modern" discovery of platinum is attributed to Spanish conquerors in the 17th century. Actually the name platinum was given by the Spanish word, platina, meaning little silver. Spaniards had discovered alluvial deposits of the rare white metal when they were mining in search for gold in the Choco region in Colombia. Paradoxically, they considered platinum as a nuisance for their mining of gold.

After the introduction of platinum into Europe in the 18th century it became a metal of interest for scientists due to its special properties. In 1751, a Swedish assayer, Scheffer, recognized platinum as the seventh existing element at that time. The French physicist P.F. Chabaneau first obtained malleable platinum in 1789 in order to produce a chalice presented to Pius VI. It seems that the British chemist W. H. Wollaston was the first person to obtain a sample of pure platinum in the early 1800s. The techniques used by Wollaston in the separation of PGMs are considered to be the basis for modern platinum metallurgy.
The production of platinum requires very complex processing techniques that were not available until the end of the 19th century. Moreover, the high melting points of platinum made it very difficult to work with it. It was only with the development of new refining techniques that platinum was more widely used for new industrial applications. On the other hand, the use of platinum in fine jewelry rose quickly in the beginning of the 20th century. Platinum was already highly appreciated for its beauty and durability.
During World War II the availability of platinum was limited since it was declared as a strategic material. Use of platinum for most non-military applications was prohibited. After the war, consumption of platinum increased due to its catalytic properties. This increase in demand followed the development of molecular conversion techniques in the refining of petroleum. In the 1970s this demand grew even more thanks to the introduction of automotive emission standards in the developed countries.
One of the most important obstacles for a more widespread use of platinum in its history has been its limited supply. At present time, deposits of platinum are concentrated in a few areas in the world, mainly in South Africa and the Russian Federation. However, in the last few decades new mines have been opened and sophisticated platinum mining techniques have been developed. Platinum has become a metal of great importance in the world and prospects for this metal are very positive.

Description/Technical Characteristics
Platinum is one of the densest and heaviest metals, highly malleable, soft and ductile. It is extremely resistant to oxidation and to corrosion of high temperatures or chemical elements as well as a very good conductor of electricity and a powerful catalyzing agent. Platinum is soluble only in aqua regia. This precious metal has silvery-white color and does not tarnish.

Platinum 

Chemical symbol
Atomic number
Atomic weight
Crystal structure
Density
Melting point
Boiling point
Vickers hardness No (annealed condition)
Electrical resistivity
Thermal conductivity
Tensile strength
Electronic configuration
Isotopes




Quality
Platinum is considered as a native element even though it is never 100% pure platinum. When extracted, platinum is rather impure and it normally contains small quantities of other elements. Well-formed crystals of platinum are very rare and the frequent appearance of platinum is in nuggets and grains. Platinum most common source is from placer deposits. The usual variety of native platinum is polyxene. It is 80 to 90 per cent platinum, with 3 to 11 per cent iron, in addition to the other platinum group metals as well as gold, copper and nickel. Native platinum is the primary ore of platinum. However, platinum may also be obtained from the very rare native alloy platiniridium. Moreover, it may be found combined with arsenic as sperrylite mineral and with sulfur as cooperite mineral, being also associated with minerals as chromite and olivine.
In jewelry platinum is mainly processed to a grade of 95% as stamped in the different jewelry items through the Pt 950 hallmark. This degree of purity contrasts with the one of other precious metals like gold, which is normally between 33 and 75%



Uses
Platinum has multiple and essential applications while new uses for platinum are constantly developed.
Platinum demand by application in 2006
Source: UNCTAD based on data from Johnson Matthey's platinum
Jewelry

Platinum jewelry demand was forecast to account for roughly 25% of total platinum demand in 2006 (dowm from 50% in 2000). High and volatile prices have adversely affected purchases of platinum across the major regions, particularly China.
This precious metal is highly valued for its beauty and purity together with its particular properties. Although in Europe and USA the normal purity is 95%, in certain countries the purity may be down to 85%. Platinum colour, strength, hardness and resistance to tarnish are some of the advantages of this metal in jewelry. It provides a secure setting for diamonds and other gemstones, enhancing their brilliance. Moreover, its flexibility is an important element for jewelry designers. Platinum jewelry is regarded as the precious metal for the "New Millenium".
Platinum jewelry demand had been increasing steadily for two decades (1980-1999). The world's leading platinum jewelry market had for long been Japan, where platinum is very popular and fashionable. However, this market has been affected by the situation of the Japanese economy during the last few years. In the meantime platinum demand has grown sharply in China, which has overtaken Japan as the world's leading platinum jewerly market. The white metal has become highly appreciated and consumed in China. As a result, platinum-manufacturing capacity has been developed in China. Europe and North America are also quite dynamic markets for platinum, particularly in rings for the bridal sector.

Autocatalyst
Platinum, together with palladium and rhodium, are primary elements in autocalysts that control vehicle exhausts emissions of hydro-carbons, carbon monoxide, oxides of nitrogen and particulate. Autocatalysts convert most of these emissions into less harmful carbon dioxide, nitrogen and water vapor. Autocatalyst was forecast to account for almost 51% of total platinum demand in 2006 (up from 25% in 2000).
Demand for platinum in autocatalysts started to increase significantly in the seventies when clean air legislation was introduced in USA and Japan. Many other countries followed this policy since then. However, in the 1990s, there was a substitution from platinum to palladium in autocatalysts in the United States, mainly due to its relatively lower cost and better performance in autocatalysts. In Europe platinum was more widely used since it is an essential element for diesel cars. Recent developments in the palladium market together with technological advances have led to a switch back to platinum. In recent years demand for platinum in autocatalysts has shown a considerable growth in emerging countries that introduced new environmental legislation. Demand for platinum in this application is expected to grow as stricter emissions standards and regulations are approved.
Electrical and electronics
Platinum is used in the production of hard disk drive coatings and fiber optic cables. The increasing number of personal computers will have a positive effect on platinum demand in the future. Other applications include thermocouples that measure temperature in the glass, steel and semiconductor industries or infra-red detectors for military and commercial applications. It is also used in multi-layer ceramic capacitors and crucibles to grow single crystals

 Platinum RTD 




platinum canopy caps

PLATINUM IPHONE MONTAGE_.jpg

Chemical
Platinum is used in fertilizers and explosives as a gauze for the catalytic conversion of ammonia to nitric acid. It is also used in the fabrication of silicones for the aerospace, automotive and construction sector. In the fuel sector it is important as a petrol additive to enhance combustion and reduce engine emissions. Moreover, it is a catalyst in the production of biodegradable elements for household detergents.
Glass
Platinum is used in glassmaking equipment. It is used in the manufacturing of fiberglass reinforced plastic and of glass for liquid crystal displays (LCD). In this context, some new developments in the production of LCD glass and cathode ray tubes, both used in computer screens should be mentioned.

Reinforcement glass fibre

The largest amount of platinum in use in the glass industry is for the production of textile glass fibre, commonly referred to as reinforcement fibre as it is mainly used for strengthening other materials. Its widest application is in glass-reinforced plastics (grp). Glass fibre producers use platinum components to channel the molten glass, but the main use of platinum and rhodium is in the fiberisation process itself. Fiberisation is the drawing of the glass fibres from a platinum alloy container called a "bushing" – a rectangular open topped box, the base of which has many precisely shaped holes, or jets, through which the fibres are drawn.

Liquid crystal displays (LCD)

LCD glass, used in applications such as digital watches and laptop computers, is the most intensive user of platinum and rhodium per unit of glass produced. This is due to the harsh conditions under which the raw materials for the glass are melted (usually at 1650oC) and the quality of glass required, which can be as little as half a millimetre thick and demands zero defects.

Cathode ray tube (CRT) displays

CRT displays refer to the monitors commonly used as TVs and visual display units (VDUs) for computers. There are two parts to the glass needed to make the CRT display - the cone glass panel that forms the back of the monitor, and the screen glass panel at the front. Platinum-rhodium alloys are used mainly in the production of the screen glass.

Optical & ophthalmic glass

In order to produce high quality optical glass, platinum equipment is used in the key areas of melting, conditioning and forming. Pure platinum is the preferred material since the use of alloys containing rhodium and, to a lesser extent, iridium, leads to unwanted colouration of the glass.

Container glass

Container glass refers to non-crystal tableware as well as bottles for drinks, jars for foodstuffs and containers for perfume and other items. The extent to which platinum is used mainly depends on the properties of the glass, which vary considerably according to its composition. Generally, the more corrosive the glass, the more platinum is required.

Ceramic glass

Commonly used in applications such as the flat glass surface of electric cooker hobs, ceramic glass has grown in demand in recent years. Large quantities of pgm equipment are used in the production of this type of glass.


Investment
Platinum is seen as an attractive investment vehicle and as a good way of hedging assets against inflation. This attraction for platinum investment is spreading worldwide and is based on platinum relative scarcity, its historical price performance and unique fundamentals. Investing in platinum may be done in futures and options or in bars, ingots and bullion coins like the American Eagle, the Australian Koala or the Canadian Maple Leaf among others.
Petroleum
Platinum is used as a refining catalyst in the petroleum industry.

Medical
Platinum is used in anti-cancer drugs and in implants. It is also used neurosurgical apparatus and in alloys for dental restorations.

 Applicationsinclude medical



Spark plugs
Most vehicles in North America use platinum-tipped spark plugs. In Europe higher durability requirements have led to an increase in the amount of platinum used in spark plugs.
Fuel cells
Fuel cells are devices that generate electric power. They are being developed as an alternative to internal combustion engines in vehicles. Most fuel cells apply proton exchange membrane technology producing energy from hydrogen and oxygen by using platinum catalysts. The use of fuel cells brings about environmental and economic advantages. They are more energy efficient and produce negligible pollution. All the major automotive companies, lead by Daimler-Chrysler, are planning to have fuel cell powered light vehicles by 2003-2004. Actually, there are already some fuel cell heavy vehicles working. However, the doubt remains since every vehicle using a fuel cell will be one that will not use a conventional autocatalyst. The effect on platinum demand will depend on which device uses more platinum. Present research is focusing on improving performance and reducing costs of fuel cells. Fuel cells can also provide stationary power generation. The use of platinum in fuel cells seems to be one of the platinum applications with best prospects for future demand.

Medical

Platinum anti-cancer drugs

Platinum has the ability, in certain chemical forms, to inhibit the division of living cells. The discovery of this property in 1962 led to the development of platinum-based drugs to treat a wide range of cancers. Cisplatin, the first platinum anti-cancer drug, began to be used in treatment in 1977. Testicular cancer was found to be susceptible to treatment with cisplatin and there were other successes with ovarian, head and neck cancers.
Researchers at the Institute of Cancer Research and the Royal Marsden Hospital in London achieved a significant step when they found a compound similar to cisplatin in terms of activity, but much less toxic. This drug, carboplatin, was first approved in 1986. Recent research has sought to identify new platinum compounds which will treat tumours which do not respond to or which become resistant to cisplatin and carboplatin. The first of these drugs to reach commercialization is oxaliplatin, which is being marketed under the trade name Eloxatin.
Upcoming platinum anti-cancer drugs include satraplatin, which is being developed for treatment of prostate cancer. It is claimed that the use of satraplatin results in a higher survival rate than with existing chemotherapy treatments. Satraplatin will also be the first platinum anti-cancer drug that can be administered orally instead of intravenously, allowing patients to be treated at home. The drug is currently undergoing clinical trials.

Platinum biomedical components

Platinum can be fabricated into very tiny, complex components. As it is inert, platinum does not corrode inside the body, while allergic reactions to platinum are extremely rare. Platinum also has good electrical conductivity, which makes it an ideal electrode material.
Pacemakers, used to treat heart disorders which result in slow or irregular heartbeat, usually contain at least two platinum-iridium electrodes, through which pulses of electricity are transmitted to stabilise the heartbeat. Platinum electrodes are also found in pacemaker-like devices which are used to help people at risk of fatal disturbances in the heart's rhythm. This risk can be minimised by implanting a device known as an Internal Cardioverter Defibrillator (ICD) which sends a massive electric charge to the heart as soon as it detects a problem.
Catheters, flexible tubes which can be introduced into the arteries, are widely used in modern, minimally-invasive treatments for heart disease. Many catheters contain platinum marker bands and guide wires, which are used to help the surgeon guide the device to the treatment site. The radio-opacity of platinum, which makes it visible in x-ray images, enables doctors to monitor the position of the catheter during treatment.

Platinum Use in Medical Devices Highlighted in April's PMR
The most recent edition of the Platinum Metals Review, PMR, features a
comprehensive review of the biomedical applications which incorporate
platinum as an integral part of devices and active pharmaceutical
ingredients used to sustain and enhance quality of life.
London, UK…The April edition of the Platinum Metals Review (PMR), the platinum industry's
leading technical journal, has published a comprehensive review of those biomedical applications

which depend upon platinum and its alloys to sustain and improve the quality of life.  The article
entitled A Healthy Future:  Platinum in Medical Applications, appears in the Platinum Metals
Review, Volume 55 Issue 2, April 2011, Pgs 98 - 107.
Despite the perception of high cost, the unique chemical, mechanical and electrical properties of
platinum have been recognized by leading medical device companies as an enabling technology
in developing next generational device with increased longevity and durability.  Because of the
metal's radiopacity, conductivity and inertness, platinum has been incorporated as an integral part
of a range of specialized devices including pacemakers, defibrillators, stents and neurostimulation
devices.
Platinum has become a reliable tool in the arsenal of medical device companies who are striving
to satisfy the growing demand for advanced medical technologies as the global population
expands and ages in both the developed and emerging economies

Industrial Applications Of Platinum

  • Nitric Acid - Platinum-based catalysts have now been used in the commercial manufacture of nitric acid for a century.
  • Silicones - Adding platinum compounds controls curing, helping to achieve the properties required for the numerous uses they have in everyday life.
  • Computer Hard Disks - Platinum improves the data storage capacity of hard disks and today, all hard disks contain platinum in their magnetic layers.
  • Electronic Components - Palladium-containing components are used in virtually every type of electronic device.
  • Crucibles - With their high melting points and resistance to chemical attack, iridium and Platinum are the preferred material of choice for crucibles.
  • Glass - Used in the production of glass, platinum's high melting point, strength and resistance to corrosion allow it to withstand the abrasive action of molten glass.
  • Medical - Platinum inhibits the division of living cells and this property has resulted in the development of platinum-based drugs to treat a wide range of cancers.
  • Sensors - Are used in a variety of applications: measuring of oxygen and NOx levels in car engine control systems; detection of carbon monoxide in home safety devices; wire, foil and disc electrodes for various sensors in medical equipment



Laser beams can now deliver energy to machines through thin air


Power up


THE Pelican, a small, remotely controlled helicopter drone weighing less than a kilogram, is powered by a battery that provides about 20 minutes’ flying. And yet, one evening last October, the Pelican took off, rose ten metres and hovered throughout the night. It was brought down in the morning only because the exhibition hall near Seattle where it was airborne was about to open for business.
This remarkable feat was achieved with the ingenious use of a laser beam. The laser, aimed continuously from the ground at photovoltaic cells on the Pelican’s underside, charged the chopper’s battery, keeping her aloft for an unprecedented 12 hours and 27 minutes. An optical-tracking system kept the laser beam on target, creating a “scientifically exciting, yet a little boring” experience, according to Michael Achtelik, an operator from the Pelican’s German manufacturer, Ascending Technologies, after a long night monitoring flight data.
Keeping drones aloft is not the only putative application of power beaming, as this technology is known. Five years ago NASA, America’s space agency, offered prize money to any team that could build a remotely powered robot able to climb quickly up a cable. Only in 2009, however, were the first of these prizes claimed, when three teams from America and Canada demonstrated climbing robots powered by lasers on the ground. LaserMotive, the Seattle company that designed the Pelican’s laser system, won $900,000 by powering a 5kg robot up almost a kilometre of cable dangling from a manned helicopter. LaserMotive’s beam, which uses enough electricity to light about 50 desk lamps, struck a photovoltaic panel on the robot, generating electricity that then turned a set of skateboard wheels which gripped the cable.

One reason NASA supports power beaming is that it hopes the technology could be used to help run a space elevator. This is a machine, familiar from science fiction, which some engineers think could be made science fact. In essence, it would be a giant cable reaching tens of thousands of kilometres into space and held in place by the centrifugal force of the Earth’s rotation. Cable-climbing robots, powered by laser beams shot upward from the ground, or downward from satellites, would take payloads to orbit. Launch rockets would thus become redundant. And that is not all. Andy Petro, of NASA’s technology office in Washington, DC, says power beaming of this sort might change the economics of space exploration completely. According to Mr Petro, lasers beamed from landing craft could power rovers in sunless areas of the moon or Mars, such as craters where water might be found.
Conventional photovoltaic cells, made of silicon, are designed to collect energy from the wavelengths of sunlight.LaserMotive uses special cells made with arsenic and gallium, elements better able to capture the near-infra-red wavelengths of its laser beam. The panel on the climbing robot, about the size of a coffee tray, harvested enough power to run a small lawnmower. One of LaserMotive’s founders, Jordin Kare, reckons that a similar laser could deliver about as much energy 20km up if the photovoltaic panel were only a few times larger.
Power beaming is also becoming more efficient. A few years ago lasers typically converted less than 40% of the electrical energy used to charge them into beam power. The figure is now about 60%, and costs have dropped—the result of efforts to develop better laser-based office printers, CD burners and even dermatological devices for the removal of excess hair. Moreover, engineers have worked out how to make laser beams more intense by using short lengths of optical fibre to narrow the beam. Such intense lasers are better suited to power-beaming because the cells that collect the light they deliver can be smaller.
The Pelican’s successful flight probably means that the first big application for power beaming will be supplying energy to drones. At the moment, most small drones rely on battery power, so their flights are short. LaserMotive reports that American army officials, including some responsible for special-forces kit, have expressed a desire to obtain power-beaming systems for drones. DARPA, the American Defence Department’s technology agency, is also sponsoring research into power beaming. British readers of a certain age may remember that the spaceships flown by Dan Dare, Britain’s answer to Buck Rogers, were powered by “impulse waves”, beamed from Earth. That piece of science fiction, too, may prove not to have been so wide of the mark.

A webless social network



 A.A.K. | MUMBAI


INDIA may be home to software giants, like Wipro or Infosys, which have thrived by harnessing the internet's potential, but few of the country's 1.2 billion people have so far embraced the web. Telecom Regulatory Authority of India reported that at the end of March the country had just 8.8m broadband connections. By contrast, it boasts some 812m mobile subscribers. According to Gartner, a market-research outfit, in 2013 Indians will send almost 192 billion text messages.
With 57m registered users, Just Dial is one of the biggest beneficiaries of Indians' love of texting. Set up in 1996 as a sort of phone-based yellow pages, it initially offered a fixed-line voice-based service dispensing information about the nearest coffee shop, electrician, tarot-card reader, hospital, or whatever else the caller happened to be looking for. Many users preferred it to the clunky, state-published phone directories. Cost was limited since all queries were handled in a single call, by a human assistant. “We would read out information which they would then write down on a piece of paper,” recalls V.S.S. Mani, the company's founder.
Then, in 2002, India discovered mobile phones. Soon, the cheapest handsets cost as little as 900 rupees ($18), with call rates as low as 1 rupee per minute. The pieces of paper were replaced by a text message. Today, 95% of Just Dial's callers ask for the response to be texted to them; this is done within a minute of their call.
Just Dial has become more than just a talking yellow pages. In many ways it is more akin to Places, a mobile app for Android and Apple's iPhone which tracks the user’s location and directs him to whatever it is he needs. Just Dial informs the caller about the nearest desired merchant, as well as several alternatives. The operator also offers to connect the caller directly, at no extra charge, to one of the company's "preferred vendors", a ruse reminiscent of Google's sponsored links. These pay Just Dial from a few thousand to several hundred thousand rupees a month to get talk-time with punters. (No pay per dial just yet, then.)
It is easy to create a user profile based on his search history and, just as in the online world, companies are willing to pay for such information. On occasions, after the caller hangs up, he may be assailed by up to four phone calls from competing vendors. This can be irksome, but many customers find it handy. (When your correspondent was stranded on a Mumbai motorway during a torrential downpour, a call from a nearby towing service came as a relief.) Of course, it means Just Dial needs to share the caller's phone number with participating businesses. Some see this as an invasion of privacy. Unsurprisingly, Mr Mani assures that Just Dial never misuses information entrusted to it by users. “The numbers we share are only to help the caller make an informed decision."
Just Dial has borrowed other ideas from the social media, too. It has its own recommendation service: before hanging up, each caller is asked to rate the last vendor discovered through Just Dial on a scale of one to five. The database now comprises more than 2.5m ratings. Another feature, called "tag friends", allows people to tag up to 25 mobile numbers whose owners also use Just Dial. Next time a user is looking for a nearby restaurant, say, the operator may warn him that the closest one has been rated poorly by his pals, whereas one just a few street down got the thumbs-up. Mr Mani also has plans to introduce a service which will alert the customer of the top deals in his area, like Groupon, which pioneered online vouchers. 
The challenge now is scaling up. Earlier this month Just Dial attracted $10m from private-equity firms SAP Ventures and Sequoia Capital. Vibhor Mehra, a partner at SAIF Capital, another private-equity outfit which has held a minority stake in Just Dial since 2006, says that the company may file for an initial public offering later this year. 
That would be a milestone in Just Dial's chequered history. Mr Mani first came up with the idea of phone-based search in 1989. It flopped, largely because of inadequate infrastructure: back then, Mumbai had only 600,000 telephone lines. The company took another hit during the dot com craze in the early 2000s. Its nascent web portal, justdial.com, failed to attract traffic and had to be shut down. (Today it is back up, with 325,000 visits a day.)
Having survived these growing pains, Just Dial now boasts more than 5m corporate listings accessible in 2,000 Indian towns and cities. But Mr Mani's ambitions extend beyond India. He wants to expand across the English-speaking world. He began last year in America, with a toll free number, 1-800-JUSTDIAL. His dream of becoming the world's leading local-search service while staying largely offline might yet prove less outlandish than it seems.

Duke researchers finds new clues to how cancer spreads



Cancer cells circulating in the blood carry newly identified proteins that could be screened to improve prognostic tests and suggest targets for therapies, report scientists at the Duke Cancer Institute.
Building on current technologies that detect tumor cells circulating in blood, the Duke team was able to characterize these cells in a new way, illuminating how they may escape from the originating tumors and move to other locations in the body.
The circulating tumor components include proteins normally seen when embryonic stem cells begin to specialize and move through the body to develop organs such as the heart, bones and skin, the Duke scientists reported this month in the journal Molecular Cancer Research.


The discovery may enhance the accuracy of blood tests that detect circulating cancer cells, giving doctors better information to gauge how a patient’s disease is responding or progressing.
“By developing a better blood test based on our findings, we may be able to identify molecular targets for therapy tailored to an individual patient’s cancer,” said Andrew J. Armstrong, M.D., ScM, assistant professor of medicine at Duke and lead author of the study.
The Duke team isolated tumor cells from blood samples of 57 patients, including 41 men with advanced prostate cancer and 16 women with metastatic breast cancer.
In the tumor cells of more than 80 percent of the prostate cancer patients and 75 percent of those with breast cancer, the researchers detected a group of proteins normally seen during embryonic development when stem cells begin to assume distinct roles.
As stem cells morph to build tissue and organs, they switch back and forth in what is known as epithelial-mesenchymal transition (EMT) and it’s opposite, mesencymal-epithelial transition (MET). Cancer cells have that same ability, changing from an epithelial cell similar to the organs from which they arose, to a mesenchymal or connective tissue-like cell. This EMT may underlie much of the treatment resistance and ability of cancer cells to spread.
Current FDA-approved blood tests that detect circulating tumor cells flag molecules associated with epithelial transitions; however, the Duke team found additional markers associated with mesenchymal origins, adding new targets that could be used to enhance the usefulness and sensitivity of the tests.
“Cancer is a hijacking of that normal embryonic stem cell process,” Armstrong said. “It reactivates this silent program that is turned off in adult cells, allowing tumor cells to move throughout the body and become resistant to therapy.”
Armstrong said the involvement of EMT/MET processes in tumor growth is a relatively new finding that is gaining acceptance among cancer scientists. The discovery by the Duke team adds strong evidence that the EMT/MET processes are underway when a patient’s cancer is spreading.
“In my opinion this work presents some of the most compelling data for the existence of epithelial-mesenchymal transitions in human cancer,” said Mariano A. Garcia-Blanco, professor of medicine, molecular genetics and microbiology, and senior author in the work.
“This work should pave the way for studies to understand the mechanisms underlying these transitions in humans and their importance in disease progression and therapy,” said Garcia-Blanco, who is also director of the Duke Center for RNA Biology.
The Duke team additionally noted that tumor cells appear to be most dangerous when they can easily transition between EMT and MET in a stem cell-like phase of changability that enables them to grow, spread and resist treatment.
That finding could provide new opportunities for novel therapies that target these morphing mechanisms.
“This is not just for a biomarker, it’s a direction to take therapies as well,” Armstrong said. “It’s a new horizon.”
______________
In addition to Armstrong and Garcia-Blanco, study authors include Matthew S. Marengo; Sebastian Oltean; Gabor Kemeny; Rhonda L. Bitting; James Turnbull; Christina I. Herold; Paul K. Marcom; and Daniel George.
The study was funded with grants from the National Institutes of Health; the Department of Defense Prostate Cancer Research Program; the Prostate Cancer Foundation; the American Cancer Society; and the Duke Cancer Institute.
Armstrong, Oltean, George and Garcia-Blanco have a patent application for the biological process used for detecting the blood markers.