Archive for the ‘Cancer Types’ Category

Identified: a critical tumor suppressor for cancer

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Posted 05 Aug 2012 — by James Street
Category Lymphoma, MYC
Posted On: August 4, 2012 – 1:31pm

R, FL – August 2, 2012 – Scientists from the Florida campus of The Scripps Research Institute have identified a protein that impairs the development and maintenance of lymphoma (cancer of the lymph nodes), but is repressed during the initial stages of the disease, allowing for rapid tumor growth.

While the study, published in the August 3, 2012 edition of the journal Cell, largely focuses on the role of this new tumor suppressor in lymphoma induced by Myc oncoproteins (the cancer-promoting products of Myc oncogenes), the authors show this circuit is apparently operational in all human tumors with MYC involvement, which is more than half of all human tumor types.

“This opens a new therapeutic avenue to exploit for cancers with Myc involvement—including relapsed metastatic tumors and refractory tumors, those that have not responded to treatment,” said John Cleveland, a Scripps Research professor and chair of the Department of Cancer Biology, who led the study.

The Myc family of oncoproteins (c-Myc, N-Myc, and L-Myc) regulate critical pathways that contribute to tumors; c-Myc expression, which is activated in human Burkitt lymphoma, is sufficient to induce the growth of several tumor types in animal models.

John Cleveland, Ph.D., a Scripps Research professor and chair of the department of cancer biology, led the study.

(Photo Credit: Photo courtesy of The Scripps Research Institute.)

In the new study, the scientists focused on precancerous and malignant Myc-expressing B cells, part of the immune system affected in human lymphoma. Using transgenic animal models, Cleveland and his team, led by the efforts of senior postdoctoral fellow Robert Rounbehler, showed that Myc-directed repression of a protein called tristetraprolin (TTP/ZFP36) was important for both the development and maintenance of cancer. The suppression of TTP is a hallmark of human cancers with MYC involvement, Cleveland noted.

The scientists’ results showed that overriding this pathway by forced expression of TTP more than doubled the lifespan of Myc transgenic mice. Strikingly, Rounbehler discovered that re-introduction of TTP into Myc-driven lymphoma totally disabled these tumors, indicating an important therapeutic target.

The authors showed that Myc regulates hundreds of genes that contain adenylate-uridylate-rich elements (AU-rich elements), which play an important role in RNA stability and are found in many messenger RNAs (mRNAs) that code for oncogenes, nuclear transcription factors, and cytokines. AU-rich elements direct the mRNA for degradation; they are thought to be vital for controlling expression during cell growth.

“Myc regulates the expression of select AU-binding proteins to control the destruction of certain mRNAs,” Cleveland said. “Also, our study strongly suggests that other AU-binding proteins may also, in fact, function as tumor suppressors in other cancers.”

Stem Cells Could Fuel Cancer Growth

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Posted 02 Aug 2012 — by James Street
Category Stem Cell Research, Stem Cell Research

By MALCOLM RITTER AP Science Writer
NEW YORK August 1, 2012 (AP)

 

How can a cancer come back after it’s apparently been eradicated? Three new studies are bolstering a long-debated idea: that tumors contain their own pool of stem cells that can multiply and keep fueling the cancer, seeding regrowth.

If that’s true, scientists will need to find a way to kill those cells, apart from how they attack the rest of the tumor.

Stem cells in healthy tissues are known for their ability to produce any kind of cell. The new research deals with a different kind, cancer stem cells. Some researchers, but not all, believe they lurk as a persisting feature in tumors.

Over the past decade, studies have found evidence for them in tumors like breast and colon cancers. But this research has largely depended on transplanting human cancer cells into mice that don’t have immune systems, an artificial environment that raises questions about the relevance of the results.

Now, three studies reported online Wednesday in the journals Nature and Science present evidence for cancer stem cells within the original tumors. Again, the research relies on mice. That and other factors mean the new findings still won’t convince everyone that cancer stem cells are key to finding more powerful treatments.

But researcher Luis Parada, of the University of Texas Southwestern Medical Center in Dallas, believes his team is onto something. He says that for the type of brain tumor his team studied, “we’ve identified the true enemy.”

If his finding applies to other cancers, he said, then even if chemotherapy drastically shrinks a tumor but doesn’t affect its supply of cancer stem cells, “very little progress has actually been made.”

The three studies used labeling techniques to trace the ancestry of cells within mouse tumors.

Collectively, they give “very strong support” to the cancer stem cell theory, said Jeffrey M. Rosen, a professor of molecular and cellular biology at Baylor College of Medicine in Houston. He did not participate in the work but supports the theory, which he said is widely accepted.

Another scientist who’s skeptical about the theory, and said he has plenty of company, said the new papers did not change his mind.

Parada’s team worked with mice genetically primed to develop a certain type of brain tumor. The scientists genetically labeled particular cells in the tumor and then attacked the cancer with the same drug given to human patients. It kills growing tumor cells and temporarily stops the cancer’s growth.

After treatment, when the tumor started growing again in the mice, the researchers showed that the vast majority, if not all, of its new cells had descended from the labeled cells. Apparently these were the tumor’s cancer stem cells, they concluded.

Parada said his team is now trying to isolate cancer stem cells from mouse brain cancers to study them and perhaps get some leads for developing therapies to eradicate them.

He also said that preliminary study of human brain tumors is producing results consistent with what his team found in the mice.

Parada’s study appears in Nature. In a second Nature report, British and Belgian researchers found evidence for cancer stem cells in early stage skin tumors in mice. And in the journal Science, a Dutch group found such evidence in mouse intestinal polyps, which are precursors to colon cancer.

Scott Kern of the Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins University in Baltimore is skeptical about whether tumors contain cancer stem cells. He said that since the new studies didn’t involve human tumors, it’s not clear how relevant they are to people.

The two European studies focused largely on lesions that can lead to tumors, he said. And as for Parada’s brain cancer study, he said he believed the results could be explained without relying on the cancer stem cell theory.

Penn researchers enlist dogs in battle against human cancers

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Posted 14 Jul 2012 — by James Street
Category Dog Osteosarcoma, listeria bacteria, vaccine
Posted: Sat, Jul. 14, 2012, 3:01 AM

By Faye Flam

Inquirer Staff Writer

Penn veterinarian Nicola Mason, left, with Sasha and the dog

TOM GRALISH / Staff Photographer
Penn veterinarian Nicola Mason, left, with Sasha and the dog’s owners, Carlos and Liliana Ruano. Sasha lost a foreleg to bone cancer and is now receiving experimental treatment.
HEALTH
 

 Sasha is still spunky at 12 – a white dog with a smattering of black, floppy ears and a sweet face. Even after she lost her right foreleg to bone cancer, her owners said, she could jump and catch a Frisbee. Unfortunately, in nearly all cases like Sasha’s, the surgery offers just a short respite before the cancer comes roaring back. Her only hope now lies with an experimental treatment being developed at the University of Pennsylvania.

Tuesday, doctors at Penn’s School of Veterinary Medicine pumped a modified listeria bacteria into her bloodstream, hoping to push her immune system to kill remaining cancer cells. If the treatment works, it is likely to be tested next on humans with this type of bone cancer, called osteosarcoma.

Veterinary scientists say such cross-species research is on the rise. While animal research has long played an important role in human medicine, an increasing number of clinical trials for dogs are being designed to help both species.

Right now, the vast majority of cancer treatments that work in mice fail in people, said immunologist Carl June, director of translational research at Penn’s Abramson Cancer Center. By testing the treatments in dogs, he said, veterinarians are helping sort out the potential winners.

Osteosarcoma is also easier to study in dogs because it’s relatively common, especially in larger breeds. In humans, it’s an orphan disease, but it takes a vicious toll. It strikes young people, most of them between the ages of 13 and 25. Often their only hope for survival is a radical amputation.

Liliana Ruano said she and her husband, Carlos, wanted a dog that could accompany the North Carolina couple on hiking and camping adventures, and Sasha turned out to be just perfect. They often visit Carlos’ family in Pennsylvania and hike with Sasha in French Creek State Park.

The first sign of trouble came earlier this year, when Sasha started limping. The local veterinarian thought it was an injury; it seemed to get better for awhile, but then it got much worse.

An X-ray revealed bone cancer, and the doctor offered grim choices. They could do nothing and their faithful hiking buddy would die in agony, or they could amputate the leg, which would give her a few months of pain-free life before the cancer returned, usually as a fatal chest tumor. Mild chemotherapy would extend her life slightly.

They opted for the surgery and chemotherapy, and Sasha came through very well. She’s running around and playing Frisbee – for now, anyway.

Concerned that Sasha’s cancer would come back, Liliana found information about the Penn trial on a Facebook page about dogs and cancer. She called to find out more and connected with Nicola Mason, who explained the treatment, its risks and benefits. Mason told them the tumor would have to be of a certain type for Sasha to qualify – expressing a marker called her2/neu. Sasha’s tumor tested positive.

Mason, who has both a veterinary degree and a doctorate in immunology, said osteosarcoma tumors that strike dogs are very similar to those that strike humans. Dog and human lymphomas are also similar, and she is also involved in a trial to treat dog lymphoma.

Treatment with listeria bacteria might sound scary because it’s associated with food poisoning, but it is disabled, Mason said. “It’s modified so it does not cause disease and is rapidly cleared.” But it should still prompt an immune response in Sasha.

Modified listeria has been tested in mice and used in some trials connected with human cervical cancer, she said. For this treatment, the listeria was also genetically modified – a gene was added to allow the bacteria to make a protein called her2/neu – the same one they tested for and was expressed in Sasha’s tumor.

The idea is to train the patient’s immune system with the her2/neu protein the way you might train a bloodhound with a piece of someone’s clothing. The immune cells are geared to attack listeria, but they will also be trained to recognize and attack cancer cells that express the her2/neu. This protein is one of the few marks that distinguishes the cancer cells from healthy ones, so the immune system should go after the cancer.

Though Sasha looks healthy now, amputations almost always leave behind a few malignant cells, which is why dogs often bounce back after an amputation but almost always get a fatal recurrence.

“They are sitting on time bombs,” Mason said. In virtually all cases, stray malignant cells eventually spread to the lungs and kill the dog. “What we’re doing with the immunotherapy is mopping up the cancer cells we can’t see,” she said. So far, they’ve signed up six dogs, and they aim to recruit 9 to 18.

Why can’t the immune system kill the cancer cells without all this help?

Our immune systems do best when fighting foreign cells, said the University of Minnesota’s Jaime Modiano, who is, like Mason, a veterinarian with a doctorate in immunology. Cancer cells are so similar to our own cells that it can be hard for the immune system to recognize them as invaders.

In a given patient, canine or human, cancer cells undergo their own version of natural selection. The ones that evade the immune system survive and proliferate, he said. Cancer cells can evolve a host of evasive maneuvers. The challenge with immunotherapy is getting around all those tricks.

Modiano says clinical trials elsewhere are testing new therapies for brain cancer and other malignancies that strike both canines and humans. Working with dogs gives them information they couldn’t get studying mice or people, he said. There is no shortage of dogs with spontaneous cases, he said, since cancer strikes about one in three dogs.

Studying dogs also allows researchers to learn at an accelerated pace – literally in dog years. If a treatment keeps a terminally ill dog alive for two years, that’s like keeping a human alive for 10 or 15 years.

Penn’s Carl June sees clinical trials with dogs as a way to take advantage of an explosion of untested but promising new approaches to fighting cancer and to accelerate the process of sorting the winners from the losers.

Immune therapies are a good case in point, he said. “This is exactly the sort of thing that should be done on a dog,” he said.

No other large animals routinely get cancer the way dogs and humans do. Monkeys rarely get cancer spontaneously, and many people have ethical concerns about giving cancer to fellow primates. Scientists see some striking similarities in the genetics and biology of dog and human cancers. Cats, too, are starting to be entered in clinical trials, but Mason said dog research is further ahead.

Sasha had her first treatment at Penn on Tuesday. She will stay several days for observation before her owners take her back to North Carolina.

Liliana Ruano says she understands the risks and potential benefits. “Dr. Mason spent a lot of time with us to make sure we were comfortable,” she said. Ultimately, she decided to go ahead because of the chance to extend Sasha’s life. “I’m not ready to let her go yet.”

 

Understanding Rechallenge and Resistance in the Tyrosine Kinase Inhibitor Era: Imatinib (Gleevec) in Gastrointestinal Stromal Tumor

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Posted 09 Jul 2012 — by James Street
Category GIST, Gleevec
Agulnik, Mark MD; Giel, Jennifer L. PhD

Abstract

Disease progression after treatment with a particular therapy, in the traditional view of cancer chemotherapy, indicates resistance to that treatment. However, targeted therapies such as tyrosine kinase inhibitors (TKIs) do not follow these same principles. The purpose of this review is to educate about TKI resistance and rechallenge in oncology, using the TKI imatinib in the treatment of gastrointestinal stromal tumor (GIST). True imatinib resistance does occur; however, in contrast to expectations with traditional chemotherapy, a number of instances of apparent imatinib resistance may not actually be true treatment resistance. For example, clinical evidence indicates that patients with metastatic or unresectable GIST that progressed after cessation of initial imatinib therapy who were rechallenged with imatinib achieved response or stable disease. Also, progression during imatinib treatment may be indicative of noncompliance or a need for dose increase rather than true resistance. The ability to rechallenge with a previously used therapy after progression on or after TKI therapy is relevant to both the adjuvant and the metastatic/advanced settings. Ongoing clinical trials, which are further examining imatinib rechallenge in combination with other agents in patients with GIST who have developed resistance to imatinib and/or another TKI, may impact the treatment paradigm for GIST.

(C) 2012 Lippincott Williams & Wilkins, Inc.

New Research Reveals Some Natural Supplements Effective Against Prostate Cancer

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Posted 03 Jul 2012 — by James Street
Category Herbs, Prostate Cancer

press release

June 21, 2012, 1:00 p.m. EDT

BOSTON, June 21, 2012 /PRNewswire via COMTEX/ — Several university studies conducted by medical researchers have had some surprising results, revealing evidence proving several common, naturally-occurring ingredients are effective in reducing or eliminating prostate cancer cells in both lab cultures and live mice studies. As a result, nutraceuticals containing extracts of these ingredients may be indicated in supporting men’s prostate health.

African Plum Tree Bark Extract – The extract of the bark of the African plum tree (pygeum africanum) is currently used in the US and Europe in the treatment of enlarged prostate (also known as benign prostatic hyperplasia, or BPH). In a recent study conducted by researchers at the University of Missouri-Columbia, pygeum africanum was shown to induce tumor cell apoptosis (tumor cell death), And laboratory mice who were fed a preparation of the pygeum extract exhibited a reduced incidence of prostate cancer compared with control mice that were fed a standard diet.

White Button Mushroom Extract – The extract of this edible mushroom (agaricus bisporus) has been indicated as successfully inhibiting the growth of prostate cancer cells. In a study carried out at the Beckman research institute, tumor cells exposed in vitro and in vivo to the extract of the white button mushroom showed a significant decrease in tumor size and reduced rates of cancer cell growth.

Sang Huang Mushroom Extract (phellinus linteus) – According to researchers at the Harvard Medical School, a preparation of phellinus linteus was injected into laboratory mice who were affected by prostate cancer. The results showed that the Sang Huang extract played a role in reducing the rate of cancer cell growth, as well as causing a significant reduction in overall tumor size.

To read abstracts of these university studies and find information on how to obtain extracts of these supplements visit the website: www.prostateph.com

Preventing Prostate CancerPreventing prostate problems and other men’s health issues depends in part on making the right lifestyle choices. Practicing good dietary habits, getting plenty of physical exercise, avoiding the use of tobacco products, and keeping alcohol consumption to a moderate level can lead to overall good health and maximize the body’s ability to fight off diseases ranging from the common cold to cancer. Nutraceuticals can play a major role in protecting a person’s health.

For additional information on men’s prostate health, visit: http://www.prostateph.com/ . John Dugan writes about Men’s health and is a contributing editor to numerous online publications.

Media Contact: John Dugan, 508-620-2862, joc@bankcardconcepts.com

SOURCE ProstatePh

Progress made against rare cancer

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Posted 02 Jul 2012 — by James Street
Category mesothelioma
MARIE MCCULLOUGH; The Philadelphia Inquirer
Published: 07/01/12 12:05 am

PHILADELPHIA – During a grueling operation early last year, when the intractable 5-pound tumor seemed to mock his skills, thoracic surgeon Joseph S. Friedberg felt buoyed by what he and his scrub-suited crew had already achieved.

The University of Pennsylvania team battles pleural mesothelioma, a rare, ferocious, incurable type of lung cancer.

Typically, patients die within a year of diagnosis. Yet more than two years after treatment at Penn, 27 out of 38 patients – 71 percent – were still alive, including four who had marked five years. These were advanced-stage cases, ostensibly hopeless, and they were defying the odds.

Friedberg, who was about to submit a study on those results for publication, knew there would be skepticism. The number of patients was small. And the treatment was almost as formidable as the disease. He spent up to 14 hours stripping out the cancer while preserving the patient’s lung; then residual malignant cells were zapped with laser light therapy.

He was disappointed, but not surprised, when the Annals of Thoracic Surgery demurred at publishing the study. “The reviewers said the follow-up time was too short and we were overestimating” the projected survival time, he recalled.

The only way to address that concern was to let more time elapse.

In May, with a fuller picture, the journal published the results, which are impressive.

This story is about those results, and how the 25 members of Penn’s pleural and mesothelioma program are making remarkable progress against a dreadful disease.

It’s also about the heartbreaking inadequacy of that progress.

“I don’t particularly consider it a victory,” said Friedberg, co-director of the program. “ ‘Good’ for me would be 10 years. Every time these patients’ cancer recurs, it kills me.”

Pleural mesothelioma is caused by exposure to asbestos, a once-ubiquitous building material. Decades after exposure, renegade cells arise in the mesothelium, a cellophane-thin membrane that lines the chest cavity, lungs, heart and diaphragm.

By the time the classic symptom of breathlessness shows up, the cancer usually has a stranglehold, invading all surfaces and organs in the cavity.

Conventional treatments – chemotherapy, radiation and surgery – have dismal outcomes. In the pivotal study of the only chemotherapy specifically approved for mesothelioma, 60 percent of patients did not respond. For the rest, it extended median survival just 13 weeks, to 12.1 months.

Mesothelioma has become a big specialty for liability lawyers, but with 3,000 new cases a year in the United States, it is hardly a hot research field.

Nonetheless, for more than two decades, Penn scientists have been pursuing innovations. They are combining conventional treatments with gene therapy, T-cell therapy and the laser technology, called photodynamic therapy.

Patients come thousands of miles to Penn after exploring their options – or lack thereof.

William J. McQueen, 63, an ear-nose-and-throat doctor from San Antonio, Texas, is one of them. Because his cancer encased one lung – the typical pattern – and because he was in good overall health, specialists at several top hospitals recommended an “extrapleural pneumonectomy.”

The harrowing surgery involves removing the lung, the lining of the chest, the heart’s sac and the diaphragm muscle, which controls breathing, then reconstructing certain tissues with high-tech fabric.

Up to 10 percent of pneumonectomy patients die of complications. The rest die of the cancer, which invariably comes roaring back, typically within months.

McQueen asked about preserving his lung but was told that would depend on the extent of his cancer – something that would be assessed on the operating table.

“I got the impression they would not take the time to strip the tumor out,” he said. “They’d go in and take the lung out. That’s what most surgeons do.”

That’s what Friedberg used to do.

Theoretically, taking the lung left minimal cancer for conventional therapies to mop up, thus lowering the chance of relapse. In reality, he could see it didn’t work. It was like uprooting a garden to get rid of weeds, only to have the weeds grow back worse than ever.

In the late 1990s, Friedberg teamed with Penn radiation oncologist Stephen Hahn, an expert in photodynamic therapy, to try it for mesothelioma.

It requires injecting the patient with a drug, a photosensitizer, that makes cancer cells ultra-sensitive to visible light. When the drug is exposed to red light, it sets off a chemical reaction that destroys the cells, damages blood vessels that feed the tumor, and activates the immune system.

The cell-killing effect only works near the surface, because red light penetrates only half an inch or less.

Regulators have approved photodynamic therapy for several cancers, but evidence that it works for mesothelioma is mixed. In the most rigorous study, published in 1997, it did not improve survival or time to recurrence.

But surgeons in that study were allowed to leave a thin layer of tumor – too much, Friedberg speculated, for the laser light to reliably penetrate.

Still, he knew that even if he cut out every speck of detectable tumor, preserving the lung would leave behind more microscopic disease than removing the organ would. So beginning in 2004, the team performed a modified pneumonectomy – removing the lung but preserving the heart sac and the diaphragm – followed by the light therapy.

Then came a patient in her 80s. Taking her lung would be too risky, agreed the physicians – Friedberg, Hahn, Daniel Sterman, Keith Cengel and Steven Albelda.

To their shock, she was back on the golf course not many months after Friedberg preserved her lung. So he preserved the next patient’s lung. And the next. With perseverance and ingenuity, he found he could save the lung no matter the extent of the tumor.

By 2008, it was clear the lung-sparing strategy was superior. The 14 patients whose lungs were removed had a median survival of only 8.4 months. But most of the 14 who kept their lungs were alive after more than two years – at least twice as long as other studies had reported for such advanced disease.

Though those with two lungs were physically better able to cope with a relapse, Friedberg believed the light therapy was playing a big role, somehow priming the immune system to keep resurgent cancer under control.

To try to prove it, the team decided to treat 24 more patients – 38 in all.

The median survival for the 38 patients Friedberg’s team treated from 2004 through 2010 was 31.7 months – more than 21/2 years – even though the cancer came back in a median time of 9.6 months.

Read more here: http://www.thenewstribune.com/2012/07/01/2200900/progress-made-against-rare-cancer.html#storylink=cpy

UC Davis Researchers Find Biomarker That Predicts Response to Chemotherapy for Osteosarcoma

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Posted 02 Jul 2012 — by James Street
Category Human osteosarcoma research, Osteosarcoma, P16

(HealthNewsDigest.com) – SACRAMENTO, Calif. — Scientists have found that a protein expressed by some cancers is a good predictor of how the cancer will respond to standard chemotherapy for osteosarcoma, the most common bone cancer in children. Knowing whether a patient’s tumor has this protein biomarker could help doctors determine if a patient should undergo standard treatment or if a more aggressive or alternative therapy may be more effective.

The study findings were published in Human Pathology and are available online at http://www.ncbi.nlm.nih.gov/pubmed/22578565.

“This is the first time that a biomarker has been identified that predicts treatment success for osteosarcoma,” said Dariusz Borys, assistant professor in the UC Davis Department of Pathology and Laboratory Medicine and lead author of the study. “It is a first step in individualizing therapy to maximize success based on a protein that the cancer expresses.”

Osteosarcoma is usually diagnosed during the teenage years. It also may affect people over 60.

Osteosarcoma is typically treated with “neoadjuvant therapy,” which involves several cycles of chemotherapy using a combination of drugs to shrink the tumor before it is surgically removed. How effective the chemotherapy is in inducing cancer cell death (necrosis) is the best predictor of a patient’s survival following surgery. But a tumor’s response to chemotherapy varies widely among patients, and until now, a way to predict whether the chemotherapy will work well has not been identified.

The investigators focused on a protein expressed by cancer cells known as P16, which inhibits cell growth. For unknown reasons, some cancers stop expressing P16. The researchers found that patients who had cancers that still expressed P16 were more likely to respond well to chemotherapy.

“It is useful to know ahead of time if patients are likely to respond to standard therapy,” said Borys. “Those who have tumors that do not express P16 would be especially good candidates for more aggressive or experimental treatments to see if they might respond better.”

The study enrolled 40 patients, aged 9 to 75 years old (median age, 15 years), with osteosarcoma at UC Davis and UC San Francisco. Pathologic specimens of the tumors before treatment were collected for study from each patient and were analyzed for P16 expression. After chemotherapy, during surgery to remove the tumor, specimens were again collected and analyzed for the extent of tumor cell death. A little more than half of the patients responded well to chemotherapy, and these patients were found to be significantly more likely to have had tumors that expressed the P16 protein.

Data on how the patients fared clinically were not available for this study, but it has been well established from other studies that the amount of tumor killed preoperatively is strongly associated with survival.

Borys said more patients will be studied to strengthen the findings, and on a molecular level, more study is needed to clarify why some cancer cells stop expressing P16.

The study was a collaboration among three institutions on the west coast (UC Davis, UC San Francisco and University of Washington) and involved pathologists and surgeons. According to Borys, pathologists traditionally have been used to help establish a diagnosis, but are now moving toward an equally important role in helping clinicians determine treatment strategies.

“Pathologists will one day be able to provide answers to better help clinicians cure their patients,” said Borys. “Our work to improve the treatment of osteosarcoma is an important step in that direction.”

The article is titled, “P16 expression predicts necrotic response among patients with osteosarcoma receiving neoadjuvant chemotherapy.”

Other UC Davis study authors were Robert J. Canter and Steve R. Martinez, surgical oncologists at the Comprehensive Cancer Center, Robert M. Tamurian of the Department of Orthopedic Surgery, John Bishop of the Department of Pathology and Laboratory Medicine and Brian Murphy of the Veterinary School’s Department of Pathology. Andrew Horvai of the UC San Francisco Medical Center was co-principal investigator with Borys. Benjamin Hoch of the University of Washington was another study author.

UC Davis Comprehensive Cancer Center is the only National Cancer Institute-designated center serving the Central Valley and inland Northern California, a region of more than 6 million people. Its specialists provide compassionate, comprehensive care for more than 9,000 adults and children every year, and access to more than 150 clinical trials at any given time. Its innovative research program engages more than 280 scientists at UC Davis, Lawrence Livermore National Laboratory and Jackson Laboratory (JAX West), whose scientific partnerships advance discovery of new tools to diagnose and treat cancer. Through the Cancer Care Network, UC Davis collaborates with a number of hospitals and clinical centers throughout the Central Valley and Northern California regions to offer the latest cancer care. Its community-based outreach and education programs address disparities in cancer outcomes across diverse populations. For more information, visit cancer.ucdavis.edu.

Celebrex-derived drug targets common childhood bone tumor

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Posted 02 Jul 2012 — by James Street
Category Dog Osteosarcoma, Human osteosarcoma research, Molecular Osteosarcoma Studies, Osteosarcoma, STAT3

June 21st, 2012

Jiayuh Lin, PhD, and colleagues at Nationwide Children’s Hospital have developed a drug to target the most common cancerous bone tumor in children, osteosarcoma, using a version of the FDA-approved drug, Celebrex. The team will soon begin testing the drug using human and canine tumor cell lines thanks to a two-year, $200,000 grant from Alex’s Lemonade Stand Foundation for Childhood Cancer.

Osteosarcoma is an aggressive bone tumor that usually develops during the period of rapid growth that occurs in adolescence. A signaling pathway known as the STAT3 pathway is common in osteosarcoma and is crucial to tumor formation and cancer progression. Blocking STAT3 signaling is considered a potential approach for treating osteosarcoma; however, few drugs are available that can inhibit STAT3 and be clinically relevant.

“One of the main barriers to developing a clinical drug to inhibit STAT3 is finding lead compounds that exhibit desirable drug properties,” says Dr. Lin, who is a principal investigator in the Center for Childhood Cancer at The Research Institute at Nationwide Children’s Hospital.

Dr. Lin and associate professor at The Ohio State University College of Pharmacy, Chenglong Li, PhD, have found that developing STAT3-selective inhibitors can be accelerated by pairing a novel STAT3 drug discovery method with drug repositioning techniques to create inhibitors with desirable drug properties. Using this method, Dr. Lin’s team has developed a STAT3-selective inhibitor, 8A, using the FDA-approved drug, celecoxib (brand name: Celebrex®, Pfizer, New York ). Celecoxib is typically prescribed to relieve pain, tenderness, swelling and symptoms of inflammatory conditions like osteoarthritis. 8A is more potent and selective than celecoxib against STAT3 signaling in osteosarcoma cells.

The new funding will allow Dr. Lin’s team to develop two additional 8A analogs that would further increase STAT3 binding, while retaining the drug properties of celecoxib. The team will then test all three versions in human and canine osteosarcoma cell lines and in a mouse tumor model. Future research will include collaboration with Cheryl London, DVM, PhD, at The Ohio State University College of Veterinary Medicine to initiate clinical trials of a lead 8A analog in dogs with spontaneous osteosarcoma. Osteosarcoma in dogs is very similar to osteosarcoma in humans. Trials will provide valuable data for human trials as well as help determine the feasibility of using lead 8A analog to treat these tumors in canines.

“This is a unique approach in osteosarcoma targeted therapy,” says Dr. Lin. “We feel confident that our findings will advance the field of childhood osteosarcoma treatments.”

Provided by Nationwide Children’s Hospita

Tumor Surgeon James C. Wittig, MD Featured in New York Magazine’s Best Doctors Issue for 2012

New York, NY (PRWEB) June 29, 2012

Dr. James C. Wittig has again been named a top orthopedic surgeon in New York magazine’s latest guide to the “Best Doctors in New York.” Time and again, Dr. James Wittig has earned the distinction of being among the finest in the country – and that’s according to leading physicians in his field.    Dr. Wittig, an Orthopedic Oncologist at Mount Sinai Medical Center, dedicates his practice exclusively to limb-sparing surgery; pediatric and adult bone and soft tissue sarcomas; benign musculoskeletal tumors; metastatic cancers; as well as complex hip and knee replacement surgery. In addition to his office at Mount Sinai Medical Center, Dr. Wittig sees patients at offices in Hackensack and Morristown, New Jersey as well as in Long Island, NY.

On any given day, you will find Dr. Wittig in surgery, making rounds or conferring with colleagues on the next best option for his patients. It is this assiduous schedule that keeps Dr. Wittig at the forefront of his field, earning him accolades yearly and again this year. In addition, he recently co-authored “Operative Techniques in Orthopaedic Surgical Oncology,” a much needed resource and whose time had come. Co-authored also by Martin Malawar, MD and Jacob Bickers, MD, the book was produced to provide a comprehensive guide on the surgical treatment for bone and soft tissue sarcoma and a heavy emphasis on limb sparing surgery.

He takes this accolade as another motivating force to continue to seek out and explore both new and technologically advanced medical treatments as well as share his experiences. The desire to help others coupled with his educational endeavors has grown tremendously from his roots as a child in Paterson to receiving his first honor in 1990, a Biology Department Honors Citation for Superior Academic Achievement followed by Summa Cum Laude status upon graduation from Seton Hall University. Four years later he received his Medical Degree from New York University School of Medicine where he was elected to the prestigious Alpha Omega Alpha (AOA) Honor Society and also served as president of the society. During medical school, he also received “Most Outstanding Research Presentation on Medical Student Assembly Day, The Lange Medical Publication Award for Outstanding Achievement as a Medical Student and the Glover C. Arnold surgical Award for the Medical Student who excelled in Surgery. From NYU he interned in General Surgery at St. Luke’s-Roosevelt Hospital Center and did his residency in Orthopaedic Surgery at Columbia Presbyterian Medical Center in New York City where he was appointed Administrative Chief Resident received the ‘Orren D. Baab Award for Excellence in Orthopedic Surgery, Member of the Senior Resident Staff who Best Exemplifies those Qualities of Academic Excellence, Clinical Proficiency and Capacity for Leadership, New York Orthopedic Hospital.’ Dr. Wittig continued to fine tune his surgical skills as a Fellow in Orthopedic Oncology at Washington Cancer Institute, Washington Hospital Center, Children’s National Medical Center, Armed Forces Institute of Pathology in Washington, DC as well as serve as a Sarcoma Consultant, Surgical Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD.

The experience and accolades he has received along his medical journey has continued to enrich his desire to teach fellow colleagues as well as secure the best treatment options available for both adults and children affected by orthopedic tumors. While an Assistant Professor of Orthopedic Surgery at NYU Medical Center he received ‘Teacher of the Year for Outstanding Leadership, Guidance and Selfless Dedication to the Residents of NYU Hospital for Joint Diseases Department of Orthopedic Surgery Class of 2007.’     His desire was also transparent when he joined Mount Sinai Medical Center and was asked to develop a multidisciplinary team to treat sarcomas and other musculoskeletal tumors. In a two year span, he has performed over 600 cases and has dramatically changed the lives of those who have met him. Dr. Wittig has been instrumental in recruiting a team of specialists who focus on diagnosing and treating sarcomas as well as other types of bone and soft tissue tumors that affect the extremities, pelvis and spine. Currently, the team consists of specialized Pathologist Dr. Roberto Garcia; Musculoskeletal Radiologist Dr. Darren Fitzpatrick; Pediatric Oncologist Dr. Birte Wistinghausen and Radiation Oncologist Dr. Vishal Gupta as well as three Physician Assistants, 2 administrative assistants, a second orthopedic oncologist, Dr. Ilya Iofin and Dr. Sheeraz Qureshi, a spine surgeon focusing on a collaborative approach for spine tumors. The newest member to join Dr. Wittig’s team is renowned sarcoma cancer researcher and medical oncologist Dr. Robert Maki. Dr. Maki is also Chief of Pediatric Oncology and the Medical Director of the Sarcoma Program at Tisch Cancer Institute of Mount Sinai Medical Center. His vast array of experience, particularly his expertise in novel therapies for treating these complex sarcoma cancers, will ensure continuous research and development in this field.

James C. Wittig, MD specializes in limb-sparing surgery; pediatric and adult bone and soft tissue sarcomas; melanoma; benign musculoskeletal tumors; metastatic cancers; as well as complex hip and knee replacement surgery. He also has special expertise with regard to tumors that affect the shoulder girdle and scapula. In addition to his office at Mount Sinai Medical Center located at 5 East 98th Street, New York, NY, Dr. Wittig has satellite offices affiliated with Hackensack University Medical Center, at Continental Plaza, 433 Hackensack Avenue, 2nd Floor, Hackensack, NJ and Morristown Memorial Hospital, at NJ Advanced Musculoskeletal Center, PA, 131 Madison Avenue, Suite 130, Morristown, NJ and ProHealth in Long Island. Currently, Dr. Wittig is Associate Professor of Orthopedic Surgery, Chief of Pediatric and Adult Orthopedic Oncology and the Sarcoma Program at Mount Sinai Medical Center in New York City as well as Chief, Orthopedic Oncology and Director, Sarcoma Section of the Cancer Center, Hackensack University Medical Center. He is a member of the American Academy of Orthopedic Surgeons; New York State Society of Orthopedic Surgeons, Inc.; and the Medical Society of New Jersey. He has published over 90 educational materials ranging from original reports, abstracts, videos and articles in the following publications: Clinical Orthopedics and Related Research, The Journal of the American College of Surgeons, American Family Physician, Journal of Arthroplasty, Radiology and Journal of Bone and Joint Surgery. He is also a prominent lecturer in the field of Orthopedic Surgery throughout the nation.

For more information about this or other related topics, or to schedule an appointment, please call (212) 241-1807, visit http://www.TumorSurgery.org or email Dr. Wittig at drjameswittig(at)gmail(dot)com.

Read the full story at http://www.prweb.com/releases/2012/6/prweb9650840.htm

Study Provides Insight Into Pancreatic Cancer Progression, New Target for Treatment

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Posted 12 Jun 2012 — by James Street
Category Immune System, Pancreatic
Released: 6/11/2012 12:10 PM EDT
Source: NYU Langone Medical Center

Mystery of How Pancreatic Cancer Escapes Immune Detection is Unraveled,
Offering Hope for Treatment

Newswise — NEW YORK, June 11, 2012 – Researchers at NYU School of Medicine have made a key discovery that could help doctors treat one of the deadliest cancers.

A new study reveals a strategy used by pancreatic cancer cells to tinker with the immune system in a way that enables them to escape destruction by specialized immune cells.

The study, funded by the National Institutes of Health, The Pancreatic Cancer Action Network and by The Irvington Institute Postdoctoral Fellowship Program of the Cancer Research Institute, appears in the June 12 issue of Cancer Cell.

Pancreatic cancer is known for its aggressive nature. Only four percent of patients survive past five years from the time of diagnosis, and currently available therapies are largely ineffective.

“It is extremely important that we learn how the advancement of pancreatic cancer is being regulated in an effort to interrupt the progression of the disease,” said senior author Dafna Bar-Sagi, PhD, senior vice president and vice dean for Science and chief scientific officer at NYU School of Medicine.

Using mouse models of pancreatic cancer, Dr. Bar-Sagi and colleagues found that a mutation of the KRAS gene, present in 95 percent of all pancreatic cancers, triggers the expression of a protein called GM-CSF. The tumor-derived GM-CSF then directs accumulation of myeloid-derived suppressor cells in the area surrounding the tumor. These cells suppress the body’s natural immune defense reaction to growing tumor cells. In this way, pancreatic cancer cells escape being seen by the body’s immune system and are free to grow and divide. Establishment of an immunosuppressive environment around pancreatic cancer cells, therefore, prevents their prompt rejection by the immune system.

By blocking production of GM-CSF in pancreatic cancer cells, the researchers found that they were able to disrupt accumulation of myeloid-derived suppressor cells, liberating the tumor-killing immune response. “Our study suggests a therapeutic strategy for harnessing the anti-tumor potential of the immune system,” Dr. Bar-Sagi explained.

“Our findings should be applicable to a significant proportion of human pancreatic cancer cases, as the vast majority of human pancreatic cancer samples that we tested express the GM-CSF protein prominently,” Dr. Bar-Sagi added. The researchers are hopeful that their findings will open new doors in therapeutic research, eventually leading to new drug therapies that block the production or function of the GM-CSF protein to allow anti-tumor immune cells to attack the cancer cells and halt tumor development.

Although the study focuses on pancreatic cancer, KRAS mutations are prevalent in a number of other cancers, including colon and lung cancer. “From a research standpoint, the contribution of KRAS mutation to the production of GM-CSF is a very exciting find, as it may have important implications for the therapeutic management of other cancers, as well,” Dr. Bar-Sagi said.

Co-authors on the study include first author Yuliya Pylayeva-Gupta, PhD, Kyoung Eun Lee, PhD, Cristina H. Hajdu, MD, and George Miller, MD, all of NYU School of Medicine.

About NYU School of Medicine:
NYU School of Medicine is one of the nation’s preeminent academic institutions dedicated to achieving world class medical educational excellence. For 170 years, NYU School of Medicine has trained thousands of physicians and scientists who have helped to shape the course of medical history and enrich the lives of countless people. An integral part of NYU Langone Medical Center, the School of Medicine at its core is committed to improving the human condition through medical education, scientific research and direct patient care. The School also maintains academic affiliations with area hospitals, including Bellevue Hospital, one of the nation’s finest municipal hospitals where its students, residents and faculty provide the clinical and emergency care to New York City’s diverse population, which enhances the scope and quality of their medical education and training. Additional information about the NYU School of Medicine is available at http://school.med.nyu.edu/.