June 29, 2007, 4:57 AM CT

'modular' Leukemia Drug Shows Promise

A new type of engineered drug candidate has shown promise in treating chronic lymphocytic leukemia in both test tube and early animal tests, a new study shows.

The agent represents a new class of agents called small modular immunopharmaceuticals. Called CD37-SMIP, the agent targets a protein called CD37 on the surface of these leukemia cells.

The study shows that the agent can successfully attach to the protein on the leukemia cells and kill them. The agent works both by triggering the cells' self-destruction and by causing a particular class of immune cells to attack them.

In an animal model, the agent worked equally as well as the drug rituximab, now routinely used to treat chronic lymphocytic leukemia (CLL) patients. Rituximab targets a different protein on leukemia cells.

The study by scientists at the Ohio State University Comprehensive Cancer Center was published online in the journal Blood.

"Our findings have significant implications for the therapy of CLL and related malignancies," says principal investigator John C. Byrd, director of the hematologic malignancies program at Ohio State 's James Cancer Hospital and Solove Research Institute.

Overall, Byrd says, "the findings indicate that this could be an effective agent for treating CLL and other malignancies, such as non-Hodgkin's lymphoma and acute lymphoblastic leukemia when they have expression of the CD37 protein."........ Posted by: Jessica      Read more         Source

June 28, 2007, 11:37 PM CT

Ablation procedure proves safe

Multiple-electrode radiofrequency ablation is a safe and effective way of treating patients with liver cancer that can be completed in less time than current ablation techniques, as per a recent study conducted by scientists at the University of Wisconsin in Madison.

One of the biggest limitations of current radiofrequency ablation techniques is the inability to effectively treat large tumors said Paul Laeseke, PhD, lead author of the study. Current radiofrequency ablation systems can only power one electrode and create relatively small ablation zones, Dr. Laeseke said. Large tumors are treated by sequentially overlapping the small ablation zones--a technique that is both complicated and time consuming, he said.

The study consisted of 38 cancerous liver tumors in 23 patients who underwent multiple-electrode radiofrequency ablation. Local control was achieved in 37 of 38 tumors, with 34 of these tumors treated during just one session. The total ablation time was reduced by approximately 54% in comparison to if the patients would have been treated using a single-electrode system, Dr. Laeseke said.

A reduction in procedure time would make staff and imaging equipment available for other cases, said Dr. Laeseke. The therapy success rates in this study are comparable to those published in the literature for smaller tumors treated with single-electrode radiofrequency, he said. In other words, the multiple-electrode system allowed us to effectively treat larger tumors in less time......... Posted by: Jessica      Read more         Source

June 27, 2007, 6:47 PM CT

Role of Enzyme in DNA Repair

Researchers from the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), National Cancer Institute (NCI), and Integrative Bioinformatics Inc. have made an important discovery about the role of an enzyme called ataxia telangiectasia mutated protein (ATM) in the body's ability to repair damaged DNA. NIAMS and NCI are part of the National Institutes of Health (NIH).

When DNA within a cell is damaged, the cell's protective mechanism must do one of two things: repair the defect or "commit suicide," says Rafael Casellas, Ph.D., an investigator in NIAMS' Molecular Immunology and Inflammation Branch and leading author of a new paper describing the discovery. But the way in which the cell performs these protective functions has been largely a mystery, says Casellas, whose research is beginning to unravel this mystery.

Casellas' research focuses largely on certain genes that are deliberately broken and repaired as part of the immune response. Through a tightly controlled process of breaking and rejoining DNA segments, immune system cells called B lymphocytes are able to produce tens of millions of different types of antibodies to fight almost limitless types of invaders. This process of genetic recombination requires the activity of repair enzymes, which must be able to recognize and repair breaks in tightly wrapped and inaccessible DNA. During immunoglobulin gene recombination, DNA is rendered accessible by the process of transcription, which unzips double-stranded DNA as part of the conversion of genetic information into functional proteins......... Posted by: Jessica      Read more         Source

June 27, 2007, 6:06 AM CT

Pitched Debate Over Anemia-Fighting Drugs

The recent issue of Elsevier's Community Oncology takes an in-depth look at the charge that ESAs, generally considered vital to cancer patients' quality of life, are overprescribed for profit. Scientists, oncologists, and critics of oncologists are in a heated debate now over the use of ESAs, or erythropoiesis-stimulating agents-drugs that fight anemia by boosting levels of oxygen-carrying red blood cells and the protein hemoglobin.

A number of cancer patients, suffering from fatigue and symptomatic anemia as side effects of their disease and its therapy, are prescribed ESAs-also known as EPO (epoetin alfa, or Procrit) and DARB (darbepoetin alfa, or Aranesp). New data-mostly from studies of off-label uses-on potentially dangerous side effects such as blood clots, and on survival rates, are prompting some researchers to recommend that the US Food and Drug Administration effectively curtail the use of ESAs. Adding fuel to this debate is the fact that the drugs are costly, and some critics have accused oncologists of overprescribing them, swayed by drug company rebates.

"The question is whether trained oncologists will be allowed to make the best clinical decision for each patient, or whether rationing-which isn't based on scientific evidence but on an economic policy tug-of-war-becomes the standard," says Lee S. Schwartzberg, MD, Editor-in-Chief of Community Oncology. "The current issue of the journal puts the debate in clear focus."........ Posted by: Emily      Read more         Source

June 22, 2007, 4:36 AM CT

New method for combating prostate cancer

A novel method of drug delivery to inhibit the growth of prostate cancer cells has been developed by a doctoral candidate in pharmacy at the Hebrew University of Jerusalem.

The student, Danny Goldstein, received the Barenholz Prize for Creativity and Originality in Applied Research for his work. The award, named for its donor, Yehezkel Barenholz, the Dr. Daniel G. Miller Professor of Cancer Research at the Hebrew University-Hadassah Medical School, was presented recently during the 70th meeting of the Hebrew Universitys Board of Governors.

Prostate cancer is the second leading cause of cancer-related death for men in the U.S. Present therapys for metastatic prostate cancer (cancer cells that spread to other parts of the body) include hormonal treatment, chemotherapy and radiotherapy, which frequently have serious side effects.

The well known drug, paclitaxel, exhibits a wide spectrum of anti-tumor activity. However, its therapeutic application in cancer treatment is limited, in part, due to its low water solubility, making it difficult to effectively deliver the drug to the points needed. It is also known to induce hypersensitivity reactions. Therefore, novel methods are needed that would allow for delivery of effective concentrations of paclitaxel over extended time intervals while minimizing toxicity......... Posted by: Jessica      Read more         Source

June 20, 2007, 8:30 AM CT

New tumour markers

The term "cancer" (from the Greek karkinos, which means sea crab) was used for the first time by Greek doctor Hippocrates five hundred years b.C. to define the tumours that he observed in his patients. Nowadays it is still difficult to diagnose, and prognosis is bad. Cancer is already the main cause of death in a number of countries, ranking even above cardiovascular diseases.

Pancreas cancer (PC), the subject of this thesis, has the poorest prognosis of all cancers: the survival rate after five years with the disease is less than 5% and on average, patients who have been diagnosed with it do not live longer than six months.

The modus operandi of cells is well known: the genes (DNA) are the masterminds of the system and their role is to give orders. Those orders are transmitted in the form of messages (RNA), which ultimately become molecules that do the work (proteins). Since all cells have similar genes, they are all able to give the same range of orders. However, depending on their role and the signs and information they receive from their surroundings, each cell type sends only specific messages at any one time. While in normal cells this process is carried out following an organized pattern, this pattern of messages changes completely in cancer cells. When pancreatic cells transform into cancer cells, they abandon their usual functions and start sending abnormal messages, which encourage them to quickly divide and invade nearby tissues......... Posted by: Jessica      Read more         Source

June 15, 2007, 12:33 AM CT

Cancer stem cells can thwart anti-cancer agents

Current cancer therapies often succeed at initially eliminating the bulk of the disease, including all rapidly proliferating cells, but are eventually thwarted because they cannot eliminate a small reservoir of multiple-drug-resistant tumor cells, called cancer stem cells, which ultimately become the source of disease recurrence and eventual metastasis. Now, research by researchers at the University of Pittsburgh School of Medicine suggests that for chemotherapy to be truly effective in treating lung cancers, for example, it must be able to target a small subset of cancer stem cells, which they have shown share the same protective mechanisms as normal lung stem cells. They are presenting this ground-breaking research at the Tissue Engineering and Regenerative Medicine International Society (TERMIS) North American Chapter meeting being held June 13 to 16 at the Westin Harbor Castle conference center in Toronto.

The University of Pittsburgh researchers, led by Vera Donnenberg, Ph.D., assistant professor of surgery and pharmaceutical sciences, University of Pittsburgh Schools of Medicine and Pharmacy, used cell surface markers and dyes to identify cancer stem cells as well as normal adult stem cells and their progeny in samples obtained from normal lung and lung cancer tissue samples. The scientists identified a very small, rare set of resting cancer stem cells in the lung cancer samples that looked and behaved much like normal adult lung tissue stem cells. Both the cancer and normal stem cells were protected equally by multiple drug resistance transporters, even if the bulk of the tumor responded to chemotherapy......... Posted by: Jessica      Read more         Source

June 15, 2007, 12:32 AM CT

Colon cancer proteins show promise for blood test

Searching for less invasive screening tests for cancer, Johns Hopkins researchers have discovered proteins present in blood that accurately identify colon cancer and premalignant polyps.

Initial studies of the proteins, CCSA-3 and CCSA-4, suggest they could be used to develop a blood test to identify at-risk individuals.

"The reality is that a number of people are not getting regular screening colonoscopies," says cancer researcher Robert Getzenberg, Ph.D. "So, ideally we'd like to identify those with some molecular for the disease and really need them".

Current screening guidelines for healthy people call for a baseline colonoscopy - colonic cleansing, fasting and heavy sedation followed by the insertion of a flexible, optical-scanning scope through the rectum into the colon -- at age 50, followed by re-screening at least every five to 10 years. Colonoscopy is not foolproof; cancers can develop between screenings.

First discovered by Getzenberg and his colleagues at the University of Pittsburgh through a protein scan, the two blood-dwelling proteins are believed to be remnants of cellular debris castoff from dead cancer cells. Eventhough the proteins' roles are not entirely clear, the Johns Hopkins researchers say they are part of the scaffolding that supports structures within a cell's control center, the nucleus......... Posted by: Jessica      Read more         Source

June 13, 2007, 1:24 PM CT

Prostate cancer risk in BRCA2 carriers

Carriers of a BRCA2 variation specific to Iceland are more likely to develop aggressive and lethal prostate cancer than noncarriers, according to a study published online June 12 in the Journal of the National Cancer Institute

Mutations in the BRCA2 gene are associated with increased prostate cancer risk, but it has been unclear whether they are related to progression of the disease.

Laufey Tryggvadttir of the Icelandic Cancer Registry and colleagues compared survival and disease progression in prostate cancer patients with the Icelandic BRCA2 999del5 founder mutation and those without the mutation. Using a pool of male relatives of women with breast cancer, researchers identified prostate cancer patients diagnosed in Iceland between 1955 and 2004. The mutation was present in 30 patients (5.7%).

The mutations carriers were younger at the time of diagnosis and had more advanced staged cancer, higher-grade tumors, and shorter median survival time (2.1 years vs. 12.4 years) compared with noncarriers.

The authors conclude that it is of great importance to study whether these results can be confirmed for carriers of mutations at other locations within the BRCA2 gene. Finally, the results indicate that in the search for new methods to predict prostate cancer progression, it may be fruitful to look for gene or protein expression patterns in prostate cancers resembling the patterns seen in BRCA2 mutation carriers......... Posted by: Jessica      Read more         Source

June 13, 2007, 1:10 PM CT

Mediterranean diet prevent colon cancer?

Are all healthy eating plans the same when it comes to cancer prevention?

Scientists at the University of Michigan Comprehensive Cancer Center are beginning a study to look at whether diet can impact a person's risk of developing colon cancer. Specifically, the scientists will compare a Mediterranean diet - high in olive oil, nuts and fish - with a standard healthy eating plan.

"Overall eating patterns appear to be more important for cancer prevention than intakes of specific nutrients or food groups. We hope this study will give us an indication of the benefits that a person's diet can have on health, particularly in terms of reducing the risk of colon cancer," says Zora Djuric, Ph.D., research professor of family medicine at the U-M Medical School and principal investigator on the Healthy Eating for Colon Cancer Prevention study.

The study will look at adults age 21 or older who have had colon polyps, colon cancer or a family history of colon cancer. Scientists hope to recruit 120 participants over three years. Participants will be randomly assigned to follow either the Mediterranean diet or the Healthy People 2010 diet for six months. A dietitian will work closely with each participant by telephone. Participants can choose foods they prefer from recommended food group lists......... Posted by: Jessica      Read more         Source