In a landmark cancer study published online in Nature, researchers at NYU School of Medicine have unraveled a longstanding mystery about how pancreatic tumor cells feed themselves, opening up new therapeutic possibilities for a notoriously lethal disease with few treatment options. Pancreatic cancer kills nearly 38,000 Americans annually, making it a leading cause of cancer death. The life expectancy for most people diagnosed with it is less than a year.

Now new research reveals a possible chink in the armor of this recalcitrant disease. Many cancers, including pancreatic, lung, and colon cancer, feature a mutated protein known as Ras that plays a central role in a complex molecular chain of events that drives cancer cell growth and proliferation. It is well known that Ras cancer cells have special nutrient requirements to grow and survive. But how Ras cells cope to actually meet their extraordinary nutrient requirements has been poorly understood—until now. In the study, led by Cosimo Commisso, a postdoctoral fellow in the Department of Biochemistry and Molecular Pharmacology at NYU School of Medicine, show for the first time how Ras cancer cells exploit a process called macropinocytosis to swallow up the protein albumin, which cells then harvest for amino acids essential for growth.

"A big mystery is how certain tumors meet their excessive nutrient demands ," says Dr. Commisso, whose work is funded in part by the Pancreatic Cancer Action Network. "We believe they accomplish this by macropinocytosis."

The findings suggest that Ras cancer cells are particularly dependent on macropinocytosis for growth and survival. When the researchers used a chemical to block the uptake of albumin via macropinocytosis in mice with pancreatic tumors, the tumors stopped growing and in some cases even shrank. Moreover, pancreatic cancer cells in mice featured more macropinosomes—the vesicles that transport nutrients deep into a cell—than normal mouse cells.

The discovery of a "protein eating" mechanism unique to some cancer cells sets the stage for drugs that could block the engulfing process without causing collateral damage to healthy cells and suggests new ways to ferry chemotherapeutic cargo into the heart of cancer cells.

"This work offers up a completely different way to target cancer metabolism," says lead principal investigator of the study Dafna Bar-Sagi, PhD, senior vice president and vice dean for Science, chief scientific officer and professor, Department of Biochemistry and Molecular Pharmacology, NYU Langone Medical Center, who first identified macropinocytosis in Ras-transformed cancer cells. "It's exciting to think that we can cause the demise of some cancer cells simply by blocking this nutrient delivery process."

Crucial to the team's findings is the work of Matthew G. Vander Heiden, assistant professor of biology at the David H. Koch Institute for Integrative Cancer Research at MIT and Christian Metallo, assistant professor of bioengineering at the University of California at San Diego, who characterized how Ras cells derive energy from the constituent amino acids released after protein engulfment.

Other key contributors include Craig B. Thompson, president and CEO of the Memorial Sloan-Kettering Cancer Center and Joshua D. Rabinowitz, professor of chemistry at the Lewis Sigler Institute for Integrative Genomics at Princeton University.

Viruses are not cells and cell structure, unlike bacteria, parasites, people and anything that is sure to take live. Note that life is first and viruses - the other. In fact, the majority of scientists consider viruses as a matter of the boundary between the living and the undead.

How is this possible? Is not that a mistake?
 
As is well known, living matter has the following immutable characteristics - ability to self-organize and self-reproduction. For this purpose, each living cell and in every living organism vital processes occur - feeding, respiration, excretion, etc., so to speak, keep cells and organisms alive. In viruses, however, things are very different.

Generally, viruses are particles (but not cells!), Representing a small amount of DNA or RNA wrapped in a protein, fewer carbohydrates and / or lipids (fatty substances). Proteins on the surface of the viral envelope, which can have various forms, recognize and provide host cell of virus in it. When the virus enters the cell, its DNA is integrated in this cell that it "forces" to form virus particles assemble spontaneously and leave the cell.

Viral just like living organisms, there are self-organization processes and reproduction. They, however, they are performed only in the host cell, and all other vital processes are absent altogether. By entering into the cell, viruses (which, incidentally, outside the cell are called virions) are completely dead particles. Only when entering it, they show some properties of living matter - samoorganizarane and reproduction. However, these qualities are not considered sufficient virus to be identified as living matter. For life is inherently inherent nutrition, respiration, excretion, etc. or summary speaking to a constant metabolism. Indeed, some organisms may greatly slow it down, but no body can stop it completely, and so called life.

Viruses do not have their own structures to carry out metabolism, and harness resources and structures of the host cell to carry out its goals. Therefore, they can not be called living. Apparently, however, they are not dead matter, since if it gets into the cell organization and show a high capacity for self-reproduction - something completely alien to the undead.
 
An interesting question is how the virus originated. It is believed that early in the evolution of the first primitive cells, viruses were parts of cells that are separate and distinct self-replicating particles. This theory is supported by the astonishing ease with which viruses penetrate into the cell and then subject yourself - it is placed entirely at their disposal, accepting them as part of ourselves.

Researchers have discovered a unique monoclonal antibody that can effectively reach inside a cancer cell, a key goal for these important anticancer agents, since most proteins that cause cancer or are associated with cancer are buried inside cancer cells. Scientists from Memorial Sloan-Kettering Cancer Center and Eureka Therapeutics have collaborated to create the new human monoclonal antibody, which targets a protein associated with many types of cancer and is of great interest to cancer researchers.

Unlike other human therapeutic monoclonal antibodies, which can target only proteins that remain on the outside of cancer cells, the new monoclonal antibody, called ESK1, targets a protein that resides on the inside of the cell. ESK1 is directed at a protein called WT1, which is overexpressed in a range of leukemias and other cancers including myeloma and breast, ovarian, and colorectal cancers. WT1 is a high priority target for cancer drugs because it is an oncogenic protein, meaning that it supports the formation of cancer. In addition, it is found in few healthy cells, so there are less likely to be side effects from drugs that target it. "This is a new approach for attacking WT1, an important cancer target, with an antibody therapy. This is something that was previously not possible," said David A. Scheinberg, MD, PhD, Chair of the Sloan-Kettering Institute's Molecular Pharmacology and Chemistry Program and an inventor of the antibody. "There has not been a way to make small molecule drugs that can inhibit WT1 function. Our research shows that you can use a monoclonal antibody to recognize a cancer-associated protein inside a cell, and it will destroy the cell." 

The first studies of the antibody are showing promise in preclinical research as a treatment for leukemia as reported March 13, 2013, in Science Translational Medicine. "ESK1 represents a paradigm change for the field of human monoclonal antibody therapeutics," said Cheng Liu, PhD, President and Chief Executive Officer of Eureka Therapeutics. "This research suggests that human antibody therapy is no longer limited to targeting proteins present outside cancer cells, but can now target proteins within the cancer cell itself."

ESK1 was engineered to mimic the functions of a T cell receptor, a key component of the immune system. T cells have a receptor system that is designed to recognize proteins that are inside the cell. As proteins inside the cell get broken down as part of regular cellular processes, molecules known as HLA molecules carry fragments of those proteins -- known as peptides -- to the surface. When T cells recognize certain peptides as abnormal, the T cell kills the diseased cell. In the current study, the investigators showed that ESK1 alone was able to recognize WT1 peptides and kill cancer cells in the test tube and also in mouse models for two different types of human leukemia. "We were surprised that the antibody worked so well on its own," said Dr. Scheinberg, senior author of the paper. "We had originally expected that we might need to use the antibody as a carrier to deliver a drug or a radioactive therapy to kill the cancer cells, but this was not necessary."

Additional studies must be done in the laboratory before ESK1 is ready to be tested in patients. But the monoclonal antibody was engineered to be fully human, which should speed the time it takes to move the drug into the clinic. Researchers expect that the first clinical trials, for leukemia, could begin in about a year.

The antibody was developed under a collaborative effort between Memorial Sloan-Kettering and Eureka, which have jointly filed for patent protection. This work was supported by grants from the Leukemia and Lymphoma Society, the National Cancer Institute, the Sloan-Kettering Institute's Experimental Therapeutics Center and Technology Development Fund, the Commonwealth Foundation for Cancer Research, the Tudor and Glades Foundations, the Merker Fund, the Lymphoma Foundation, and the Mesothelioma Applied Research Foundation.

http://www.sciencedaily.com

Catalog number : ISB01L
Quantity: 1L
Availability: Yes
Details:

InstantBlue™
InstantBlue is the fastest ready-to-use stain available and been optimised to give well-defined protein bands in a single step.
Specially formulated for ultra-fast, sensitive and safe detection of proteins, staining takes minutes without the need to wash, fix, microwave or destain.
Other benefits include high sensitivity (as little as 5 ng per band with BSA - See FAQs), low background staining and non-toxic formulation.
Ultra-fast staining - providing results in 15 minutes or less.
Single step procedure - no need to wash, fix, microwave or destain. Just take the gel out of the cassette and place in a container with InstantBlue.
High sensitivity - approximately 5-25ng of protein detected per band.
Super-Low background staining - Improves overall gel resolution and sensitivity and no possibility of over staining means that you can leave your gel in the stain indefinitely and still be able to read it.
Quantitative - Same gel-to-gel performance ideal for quantifying protein by densitometry
Non-toxic - ideal for regular use and disposal.
Mass Spec Compatible.

Introduction:
InstantBlue™ is a ready-to-use, proprietary Coomassie® stain that is specially
formulated for ultra-fast, sensitive and safe detection of your proteins. Protein
gels can be stained in minutes without the need to wash, fix or destain.
Only proteins are stained resulting in well defined blue bands on a highly
transparent background. The reduction of background interference results in a
better signal to noise ratio and may also have a positive impact on the overall
resolution and sensitivity.
The InstantBlue formulation is non-toxic and does not contain any methanol.
Proteins stained using the InstantBlue stain are also compatible with mass
spectrometry (MS) analysis.

Contents:
1L reagent, containing Coomassie dye, ethanol, phosphoric acid and solubilizing
agents in water. (Caution: Phosphoric acid is a corrosive liquid.)

Storage:
Upon receipt store at + 4°C. Discard any reagents that show discoloration or
evidence of microbial contamination. Be sure to keep the bottle capped when not
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 Price: 144 EUR