April 23, 2007, 9:39 PM CT

New Lung Cancer Treatment

Scientists at the Ireland Cancer Center of University Hospitals Case Medical Center have developed methods for treating lung cancer cells that have become resistant to new anti-cancer agents.

Led by Balazs Halmos, MD, hematologist/oncologist with the Ireland Cancer Center, the research team followed up on their prior study, reported in the New England Journal (NEJM), which observed that lung cancer cells can become resistant to novel targeted agents, such as Tarceva (erlotinib), a medicine in widespread use for non-small-cell lung cancer (NSCLC). Tarceva is among a new generation of cancer therapies that disrupt the molecular target responsible for stimulating tumor growth. The drug targets the receptor for the epidermal growth factor protein (EGFR) to halt the spread of cancer cells. Clinical applications of the new drug initially yielded good results with approximately 10 percent of patients experiencing complete remission of their disease.

However, in spite of the treatment's initial success, patients inevitably suffered a relapse of their disease. Dr. Halmos' studies confirmed the existence of a mutation, and insertion of this mutation into test cells rendered them resistant to Tarceva. These cells became resistant by undergoing a miniscule molecular change in the EGFR protein that the medicine targets. Further analysis revealed that the newly identified mutation was altering the protein's drug-binding pocket and thereby changing the "keyhole" so that the "key" Tarceva no longer fit. The scientists observed that new second-generation Tarceva-like medications can overcome this change and such drugs are now in development, including in clinical trials at the Ireland Cancer Center......... Posted by: Jessica      Read more         Source

April 21, 2007, 6:41 AM CT

Knocking Out The Survival Protein

An effective way to fight leukemia might be to knock out a specific protein that protects cancer cells from dying, a new study shows.

The findings suggest that a drug that can block this "survival protein" might on its own be an effective treatment.

But such a drug used in combination with several existing drugs might also offer an effective one-two punch against drug-resistant forms of chronic lymphocytic leukemia (CLL) and acute lymphoblastic leukemia (ALL). The two forms of cancer kill about 20,500 Americans yearly.

The survival protein is called Mcl1. It commonly helps keep normal cells healthy and is involved in the development of the components of the immune system, but it can also help prolong survival of cancer cells.

Cells with an overabundance of the protein are also more resistant to anticancer drugs such as rituximab, which has revolutionized the therapy of certain chronic and acute leukemias.

The study by scientists at the Ohio State University Comprehensive Cancer Center is published online in the journal Clinical Cancer Research.

"Our findings demonstrate that Mcl1 may be an effective target for drugs directed against CLL and ALL," says principal investigator John C. Byrd, professor of internal medicine and director of the hematologic malignancies program at Ohio State's James Cancer Hospital and Solove Research Institute......... Posted by: Jessica      Read more         Source

April 15, 2007, 8:53 PM CT

MicroRNAs as tumor suppressors

In the May 1st issue of G&D, Drs. Yong Sun Lee and Anindya Dutta (UVA) reveal that microRNAs can function as tumor suppressors in vitro.

"Overexpression of HMGA2 is an important feature of many medically important tumors like uterine fibroids, explains Dr. Dutta. It is very exciting to realize that microRNAs have an important role in suppressing the overexpression of HMGA2, and so may have a role in the causation and perhaps the cure of a disease that is responsible for the vast majority of hysterectomies in the Western world".

Studying chromosomal HMGA2 translocations that are associated with human tumors, the researchers found that in normal cells, a microRNA called let-7 binds to the 3 end of the HMGA2 mRNA transcript and suppresses its expression in the cell cytosol. However, chromosomal breaks that shorten the 3 end of the HMGA2 transcript, and prevent let-7 binding, result in aberrantly high levels of HMGA2 expression and tumorigenesis. This paper establishes that HMGA2 is a target of let-7, and that the let-7 microRNA functions as a tumor suppressor to prevent cancer formation in healthy cells......... Posted by: Jessica      Read more         Source

April 15, 2007, 8:37 PM CT

Predicting Early Liver Cancer

Scientists at Columbia Universitys Mailman School of Public Health have discovered a means for early detection of liver cancer. Using DNA isolated from serum samples as a baseline biomarker, the researchers examined changes in certain tumor suppressor genes that have been linked to the development of liver carcinomas. This is the first study to prospectively examine potential biomarkers for early detection of liver cancer in high-risk populations, including those with chronic hepatitis B and C virus infections.

Since most hepatocellular or liver carcinomas (HCC) are diagnosed at an advanced and commonly fatal stage, the development of screening methods for early detection is critical. HCC is one of the most common and rapidly fatal human malignancies. Worldwide, the almost 500,000 new cases and nearly equivalent number of fatalities illustrates the lack of effective therapeutic alternatives for this disease.

The Mailman School scientists and his colleagues studied the blood of patients enrolled in a cancer screening program in Taiwan, who provided repeated blood samples previous to diagnosis. A total of 12,000 males and over 11,900 females recruited in 1991-2 are being followed. Screenings performed by the team of Mailman School researchers found changes linked to cancer in serum DNA, presumably released from the tumor, one to nine years before actual clinical diagnosis......... Posted by: Jessica      Read more         Source

April 13, 2007, 4:53 PM CT

Gay men have higher prevalence of eating disorders

Gay and bisexual men may be at far higher risk for eating disorders than heterosexual men, as per a research studyconducted at Columbia University's Mailman School of Public Health. In the first population-based study of its kind, the scientists observed that gay and bisexual men have higher rates of eating disorders. The findings are published in the April 2007 issue of International Journal of Eating Disorders.

Scientists Ilan H. Meyer, PhD, associate professor of clinical Sociomedical Sciences at the Mailman School of Public Health and principal investigator, and Matthew Feldman, PhD, of the National Development and Research Institutes and first author, surveyed 516 New York City residents; 126 were straight men and the rest were bisexual men and women.

As per the study results, more than 15 percent of gay or bisexual men had at some time suffered anorexia, bulimia or binge-eating disorder, or at least certain symptoms of those disorders -- a problem known as a subclinical eating disorder, compared with less than five percent of heterosexual men. In contrast, sexual orientation did not seem to influence the risk of eating disorder symptoms among women. Just below 10 percent of lesbian and bisexual women and eight percent of heterosexual women had ever reported having a subclinical eating disorder......... Posted by: Jessica      Read more         Source

April 12, 2007, 6:12 PM CT

One of largest in GIST study and Gleevec

Gleevec, a pill developed in conjunction with the Oregon Health & Science University Cancer Institute is again showing excellent results in preventing a cancer recurrence.

In a major news release from the National Institutes of Health today it was stated that: preliminary results from a large, randomized, placebo-controlled clinical trial for patients with primary gastrointestinal stromal tumor (GIST) showed that patients who received imatinib mesylate (Gleevec) after complete removal of their tumor were significantly less likely to have a recurrence of their cancer in comparison to those who did not receive Gleevec.

The clinical trial was sponsored by the National Cancer Institute, part of the National Institutes of Health, and conducted by a network of scientists led by the American College of Surgeons Oncology Group.

"This is a major breakthrough that will change the way this type of cancer is treated," said Charles Blanke, M.D., F.A.C.P., leader of the Solid Tumors Program at the OHSU Cancer Institute and professor of medicine (hematology and medical oncology).

Scientists in the multi-site study observed that approximately 97 percent of patients who received Gleevec one year after surgery were alive without a recurrence of their cancer, in comparison to approximately 83 percent who received one year of a placebo. That means that there is a 70 percent reduction in risk of occurrence. It was also observed that Gleevec was well tolerated by most patients in the study. Mild side effects included nausea, diarrhea and swelling. More than 700 patients were enrolled in the study. Patients on placebo who had a recurrence of their cancer were given Gleevec......... Posted by: Jessica      Read more         Source

April 12, 2007, 6:01 PM CT

Low education and lower quality of life for prostate cancer patients

Among men who have received similar treatments for prostate cancer, those with less education particularly those who did not graduate from high school experience a significant drop in their quality of life after treatment compared with men who have more education, according to a study led by researchers at the San Francisco VA Medical Center (SFVAMC).

These men did not start out with a lower quality of life before cancer, says lead author Sara J. Knight, PhD, a staff psychologist at SFVAMC. Whats surprising is that after treatment, they have clinically significant problems across the board mental and emotional as well as physical in managing their lives.

The authors acknowledge that low educational level is often associated with lower income, which can lead to lower quality of life, but stress that for the men in their study, low education alone was associated with lower quality of life, irrespective of income. In our analysis, its their lower educational level that has made them more vulnerable to the effects of prostate cancer and its treatment, says Knight, who is also an assistant professor of psychiatry and urology at the University of California, San Francisco (UCSF).

The paper is available in the on-line Early View section of the journal Cancer......... Posted by: Jessica      Read more         Source

April 11, 2007, 11:03 PM CT

Deadly Secrets Of Ovarian Cancer

A new University of Michigan Medical School study sheds light on cell defects that lead to one common type of ovarian cancer and puts forth a promising new mouse model that already is being used for preclinical drug testing.

The study, published in the recent issue of Cancer Cell, focuses on ovarian endometrioid adenocarcinoma, the second most common form of a baffling, deadly disease for which early detection methods and effective treatments have been elusive so far. The American Cancer Society estimates there will be 22,430 new cases of ovarian cancer and 15,280 deaths from the disease in the United States this year.

The new mouse model developed in the U-M lab is based on molecular defects shown to be present in human ovarian tumor cells, says senior author Kathleen R. Cho, who treats patients as a member of the U-M Comprehensive Cancer Center. Chos and others existing mouse models, if designed to mimic the four major types of ovarian cancer, should provide key tools for learning how gene mutations and cell changes lead to disease, and for finding treatments during ovarian cancers early stages, when treatments are most likely to be effective.

"We need models to do preclinical testing of new drugs that target the specific molecular defects in a patients tumor cells," says Cho, a professor of pathology and internal medicine at the U-M Medical School. Using the genetically engineered mice her lab developed, one preclinical study is already under way, testing an existing drug called Rapamycin. The labs mouse model can also be used to test new drug candidates that inhibit the cell-messaging systems defective in ovarian endometrioid adenocarcinoma......... Posted by: Jessica      Read more         Source

April 3, 2007, 10:52 PM CT

Depiction of Tobacco Smoking in Movies

Harvard School of Public Health (HSPH) today is releasing materials presented to the Motion Picture Association of America (MPAA) in a scientific briefing requested by the MPAA last February 23, 2007 in Hollywood on the health impact of youth smoking and the behavioral influence of films that depict tobacco use.

The presentations can be accessed at www.hsph.harvard.edu/mpaa/.

From the perspective of public health, tobacco use is the largest preventable cause of death in the U.S. The Centers for Disease Control and Prevention (CDC) estimates that 438,000 people in the U.S. and 5 million worldwide die prematurely each year from tobacco-related disease.

The presentations lay the foundation for the recommendation of Dean Barry R. Bloom of the Harvard School of Public Health that the MPAA take substantive and effective action to eliminate the depiction of tobacco smoking from films accessible to children and youths.

HSPH has long been active in pressing for control of tobacco and smoking. In 1981, Professor Dimitrios Trichopoulos of the School's Department of Epidemiology first described the health effects of secondhand smoke, linking it to increased lung cancer risk in people who had never smoked themselves.

In 1999, Associate Dean Jay Winsten, Director of the Center for Health Communication at HSPH, and Susan Moses, Deputy Director, went to Hollywood to advocate for avoidance of smoking in youth-rated movies. In December 2006, the new chairman and CEO of the MPAA, Dan Glickman, sent a letter to Dean Bloom asking for HSPH recommendations on smoking in films, and later invited him to make a scientific presentation on the impact of youth smoking and the behavioral influence of movies that depict tobacco use......... Posted by: Jessica      Read more         Source

April 1, 2007, 9:19 PM CT

Genetic Risk Factors For Prostate Cancer

A study led by scientists at the Keck School of Medicine of the University of Southern California (USC) and Harvard Medical School has identified seven genetic risk factorsDNA sequences carried by some people but not othersthat predict risk for prostate cancer. As per the study's findings, these risk factors are clustered in a single region of the human genome on chromosome 8 and powerfully predict a man's probability of developing prostate cancer. The paper would be reported in the online edition of Nature Genetics on April 1.

"The study has identified combinations of genetic variants that predict more than a fivefold range of risk for prostate cancer," says senior author David Reich, assistant professor of genetics at Harvard Medical School and associate member of the Broad Institute of Harvard and MIT. "Both high- and low-risk combinations of variants are common in human populations".

"The identification of these genetic variants is an important step in helping us understand the higher risk for prostate cancer in African Americans compared with other U.S. populations and, more importantly, why some men develop prostate cancer and others do not," says lead author Christopher Haiman, assistant professor of preventive medicine at the Keck School of Medicine of USC......... Posted by: Jessica      Read more         Source