June 10, 2007, 8:53 PM CT

Folic Acid No Benefit To Prevet Precancerous Colon Tumors

Taking folic acid supplements does not reduce the risk of developing premalignant tumors in the colon and may even increase the risk, a new study has observed.

We had great hope that folic acid would be a very cheap and effective agent to prevent large bowel adenomas. We expected that folic acid would decrease the risk for colorectal cancers, perhaps as much as 40 percent. So these results are disappointing, said Robert Sandler, M.D., a co-author of study and chief of the division of gastroenterology and hepatology in the University of North Carolina at Chapel Hill School of Medicine.

In addition, the government-mandated addition of folic acid to common grain-based foods such as bread, flour and pasta may be a contributing factor to increased risk and thus research into this possibility should have a high priority, the study authors concluded.

Sandler said there is no reason for people to believe that fortified foods are risky and should be avoided. At the same time, he said, there is now reason to doubt that folic acid fortification will prevent colorectal cancer, which is one of the more common cancers.

Women who are contemplating pregnancy or in early pregnancy should continue to seek out folic acid-fortified foods and take supplements, Sandler said. The rest of us should await more data before we change our eating patterns or before policymakers revisit food supplementation......... Posted by: Jessica      Read more         Source

June 6, 2007, 9:26 PM CT

Big power of small RNAs, in halting cancer

Cold Spring Harbor Laboratory (CSHL) researchers led by Lin He, Xingyue He, and Professor and Howard Hughes Medical Investigator (HHMI) Greg Hannon have identified a family of micro RNAs (miRNAs) that enable a critical tumor suppressor network, called the p53 pathway, to fight cancer growth. At CSHL, we are moving simultaneously on several fronts to understand the p53 pathway because damage to this pathway is something that almost all cancers have in common, said CSHL Cancer Center Deputy Director and HHMI Scott Lowe.

Collaboration among different CSHL research laboratories has not only found that p53 can arrest the growth and even eradicate cancers, but weve revealed something very surprising about what makes this pathway so powerful, said Hannon. CSHL research published by Nature earlier this year, concluded that even in the latest stages of cancer, reactivation of a previously damaged p53 pathway caused cancer tumors to stop growing and even eliminate themselves by activating an immune response in surrounding healthy cells. Most suspected that proteins would be revealed as key to the power of p53, but this latest research published June 6 by Nature now identifies miRNAs as a critical force behind the anti-proliferation potential of p53.

Expression of most miRNAs is reduced in tumors, suggesting that some miRNAs act to prevent tumor formation. By comparing levels of miRNAs in cells with a variety of pre-cancerous genetic lesions, CSHL researchers found a connection between changes in the p53 pathway and the loss of a specific family of miRNAs, known as miR-34. The fact that p53 uses miRNAs to stop tumor cell growth reveals a completely new dimension of this critical cancer fighting pathway and its ability to trigger the genetic death of cancer cells. Our findings certainly lead to a deeper understanding of a critical tumor suppression mechanism but also may provide insight into how to best engage the p53 pathway to treat cancer by killing tumor cells, said He......... Posted by: Jessica      Read more         Source

May 31, 2007, 11:53 PM CT

Blood test may help signal tumor's remission

A blood test that detects proteins usually released by a growing tumor could one day become a useful tool for monitoring the effectiveness of chemotherapy and radiation therapy in people with advanced throat cancer, as per a research studyreported in the June 1, 2007, issue of Clinical Cancer Research Researchers in the National Institute on Deafness and Other Communication Disorders (NIDCD) and National Cancer Institute (NCI), two of the National Institutes of Health (NIH), in collaboration with scientists of the University of Michigan, observed that throat cancer patients who showed a decline in several cancer-related proteins following chemotherapy and radiation therapy were more likely to remain in remission, while those who experienced a large rise over time in those proteins frequently exhibited a return of throat cancer. The findings could help lead to the development of a blood test that enables doctors to detect the recurrence of throat cancer early on, when there is still time to pursue a second line of therapy, such as surgery or drug treatment.

Cancers of the head and neck are insidious because surgical removal of the tumor can severely impair a persons ability to talk and to swallow, said NIDCD Director, James F. Battey, Jr., M.D., Ph.D. A blood test that enables doctors to closely monitor a patients rehabilitation while sparing the patients voice, speech, and swallowing ability is an excellent example of the predictive, preemptive, and personalized approach to medicine that the NIH strives for......... Posted by: Jessica      Read more         Source

May 25, 2007, 7:19 PM CT

PSA velocity predicts worse outcome

The most significant single predictor of aggressive prostate cancer is an elevated rate of increase in prostate specific antigen (PSA) levels, as per a new study. Reported in the July 1, 2007 issue of CANCER, a peer-evaluated journal of the American Cancer Society, the study observed that a pre-treatment rate of PSA increase, called PSA velocity, of more than 2 ng/ml/year was strongly linked to a high risk of death from prostate cancer. Elevated PSA velocity was a stronger poor prognostic factor than any other single high-risk indicator, such as a biopsy Gleason score greater than 7, a PSA level of 10 ng/ml or an advanced disease category.

Prostate cancer is expected to be diagnosed in more than 200,000 American men in the U.S. this year and cause more than 27,000 deaths, the leading cause of cancer death after lung cancer in U.S. men. Most tumors are slow growing and asymptomatic, and the disease affects primarily men over 50 years old. As a result, most men diagnosed with prostate cancer die of other age-related causes.

However, in a significant subset of patients with prostate cancer, the cancer will be aggressive and quick enough to cause morbidity and death. Identifying these men is critical to reducing deaths from prostate cancer. Scientists have identified several indicators with the potential to identify high-risk patients and developed various algorithms, using such factors as the microscopic features of the tumor (i.e., Gleason score), size, spread of the disease, and location of disease, to determine prognosis. However, recent trends suggest that these factors are not effective and that better indicators are needed. Calculating PSA velocity has shown promise as a prognostic indicator. Studies suggest that PSA velocity more than 2 ng/ml/year strongly suggests aggressive disease. Understanding its significance after therapy, especially relative to other risk factors, is critical to identifying high-risk patients......... Posted by: Jessica      Read more         Source

Fri, 25 May 2007 05:04:53 GMT

Anti-smoking: The Smoking Jacket

This is yet another innovative anti-smoking campaign to urge people to stay away from smoking. The campaign is focusing on the self-awareness drive as the person wearing it may be influenced to quiThe modus operandi of the jacket: the smoker exhales cigarette smoke into a one-way air valve in the collar, trapping it in. The smoke is then guided through some tubing to a pair of plastic lungs on the front of the jacket. Inside the lungs is air-filter material which darkens to a brownish stain after repeated exposure to smoke.

The jacket has reportedly received overwhelming response from people across, some smokers wanted to use the jacket even when they are not smoking. However, it could not be ascertained that how many of them eventually quit smoking after wearing the jacket. In addition to it, there is one more advantage of this jacket as it could reduce second hand smoking to some extent.

Via I Believe in Adv Posted by: Balendu      Read more     Source

May 23, 2007, 8:25 PM CT

Stem cells may look malignant, not act it

Bone marrow stem cells attracted to the site of a malignant growth frequently take on the outward appearance of the cancerous cells around them, University of Florida scientists report in a paper would be reported in the recent issue of Stem Cells.

But whether that enables them to fuel cancer's ability to develop and then spread, as some researchers suspect, is not entirely clear. The findings, available early in this month's online edition of the journal, actually contest the increasingly popular theory that bone marrow stem cells seed cancer. Instead, these cells might simply look like cancer, not act like it.

"They have the same kind of surface proteins," said study author Chris Cogle, M.D., an assistant professor of medicine at the UF's College of Medicine Program in Stem Cell Biology and Regenerative Medicine. "They have the same skin. The next question is 'Do they have the same guts"'.

"Our results indicate these cells act as developmental mimics; they come in and look like the surrounding neoplastic tissue, but they aren't actually the seed of cancer," said Cogle, who also is affiliated with the UF Shands Cancer Center. "At the worst, these cells could help support malignant tissue by providing it with growth factors or proteins that help the cancer grow and survive. At the very least, these marrow cells are just being tricked into coming into the malignant environment and then made to walk and talk like they don't commonly do"......... Posted by: Rose      Read more         Source

May 21, 2007, 12:28 AM CT

Caspase-14 protects skin against UVB and dehydration

Ultraviolet rays can be harmful to our skin and pave the way to the onset of skin cancers. VIB scientists connected to Ghent University have demonstrated that the caspase-14 protein - whose function has been unknown up to now - not only plays a role in maintaining the balance of moisture in the skin but also offers protection against UVB rays. Future strategies that increase the production of caspase-14 will open new possibilities for fortifying the skin as a barrier against all kinds of stress.

Sunbathing and the pernicious consequences for our skin

Sunlight is needed for the development of our bodies and minds. Still, we should not expose ourselves to it too often. The UV index provides an indication of the true intensity of the suns rays and the risks that go along with them.

UV rays cause functional alterations in the most important components of our skin: the keratinocytes. In addition to causing normal sunburn and suppressing our immune responses, UVB damages the DNA in our cells, which can lead to cancer. In the last 15 years, the number of new cases of melanoma (the most dangerous skin cancer in Belgium) has practically doubled to 1500 cases per year.

Caspase-14

Caspases are proteins that are involved in inflammation reactions and in programmed cell death or apoptosis. Apoptosis is important in all stages of life. During embryonal development, for example, apoptosis ensures that undesirable or outmoded tissues disappear. In the mid-1990s, Peter Vandenabeele and colleagues were able to isolate 9 caspase family members in mice. The properties and substrates of many caspases are already known. However, caspase-14 is a maverick in that it is found very specifically in the skin and is activated during the last stage of skin cell maturation. Due to the action of caspase-14, the outer epidermis of our skin contains dead cells that are released as flakes of skin......... Posted by: Jessica      Read more         Source

May 13, 2007, 10:03 PM CT

Agent Protects Cells From Lethal Effects Of Radiation

Using this agent in mice, the researchers observed that the therapy helped shield rapidly dividing cells that are most vulnerable to radiation-induced death, providing proof in principle that it is possible to fend off radiation damage, as per a research studyreported in the recent issue of Biochemical and Biophysical Research Communications.

Current therapys for severe radiation exposure, also called acute radiation syndrome, are limited to drugs that boost the production of blood cells and platelets, but this approach is futile if underlying stem cells are also killed off. Moreover, there are no available therapys that can be given after exposure to limit damage to cells.

"We are using an entirely different approach," says Clayton Hunt, Ph.D., of the Department of Radiation Oncology. "Rather than ramp up the production of blood cells, we are trying to prevent radiation-induced cell death from occurring in the first place."

The scientists developed the agent by attaching a portion of the Bcl-xL protein already known to block cell death - a snippet called BH4 - to the HIV protein TAT, which can deftly carry other molecules into cells. They gave the agent intravenously to mice exposed to 5 Grays of radiation. In humans, this level of exposure would cause a sharp drop in blood cells, leaving individuals with an increased risk of infection and bleeding......... Posted by: Jessica      Read more         Source

May 7, 2007, 10:49 PM CT

Steep Cost For Health Care And Patients

The drug trastuzumab (Herceptin) is used to treat HER2-positive breast cancer (a type of breast cancer that overexpresses the HER2 gene and accounts for about 25% of all breast cancers). Trastuzumab treatment improves the chances of survival; however, it has deleterious side effects and is expensive. Thus, it is important to accurately determine the patients HER2 status. The challenge is to develop a testing strategy that is both accurate and economical. A false-negative test result can mean a woman will not receive a life-prolonging drug, and a false-positive result can lead to unnecessary, expensive drug therapy.

In this systematic review, Dendukuri and his colleagues compared the cost-effectiveness of 7 strategies (based on a combination of 2 tests) to diagnose HER2 status. They observed that the most cost-effective strategy is to screen all women who have newly diagnosed breast cancer with immunohistochemistry and to confirm ambiguous or positive test scores with fluorescence in situ hybridization.

In a related commentary, Brian Goldman notes that the example of trastuzumab and the HER2 gene illustrates both the promise and the perils of gene patenting. Even though genes occur naturally in humans, it is the person who discovers a gene who commonly holds the patent for it......... Posted by: Jessica      Read more         Source

May 6, 2007, 5:18 PM CT

CT colonoscopy almost as good as regular colonoscopy

Nearly 90% of colon polyps greater than or equal to 6 mm in size detected at CT colonoscopy were demonstrated to represent true polyps at subsequent optical colonoscopy (the traditional method of viewing the colon and removing premalignant growths), as per a new study by scientists from the University of Wisconsin Hospital and Clinics in Madison, WI.

"We analyzed the findings of 363 CTC-detected lesions in 244 patients who subsequently underwent optical colonoscopy," said Tyler Prout, MD, lead author of the study. The scientists observed that optical colonoscopy verified the presence of polyps in 321 of the 363 CTC-detected instances, making for an overall positive predictive value of 88.4%, he said. In addition, the combined group of polyps with either sessile or pedunculated morphology yielded a matching lesion at optical colonoscopy 91.8% of the time, Dr. Prout added.

"From a practical standpoint, this is very important, because if CTC is to be an effective screening tool it, must not only have a high sensitivity, but have sufficiently high concordance rate at subsequent optical colonoscopy to avoid unnecessary colonoscopies," said Dr. Prout.

Exact polyp size had little effect on the concordance rate, said Dr. Prout. "In our more recent experience, we do nearly as well detecting the smaller 6-7 mm polyps as those that are 1 cm or greater. Moreover, when comparing these results to our earlier experience, we find our positive predictive value at the 6-7mm polyp size threshold to be much improved; now 85%, whereas it was previously just over 50%," said Dr. Prout. "We think that this finding can be attributed to a combination of factors, some of the most important of which include colonic preparation and method of image analysis. Our colonic preparation includes both fluid and stool tagging. For image analysis, we employ a primary 3D evaluation complemented by focused review of 2D multiplanar reformats for confirmation. This is in contradistinction from a number of studies that utilize primary 2D interpretation," said Dr. Prout......... Posted by: Emily      Read more         Source