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Showing posts with label breast cancer. Show all posts
Showing posts with label breast cancer. Show all posts

Portable Breast Scanner Allows Cancer Detection in the Blink of an Eye

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A new portable scanner based on radio frequency technology can show in a second the presence of tumors -- malignant and benign -- in the breast on a computer. The red dot indicates the presence of a tumor.
Women could have a fast test for breast cancer and instantly identify the presence of a tumor in the comfort of their own home thanks to groundbreaking new research from the University of Manchester.
Professor Zhipeng Wu has invented a portable scanner based on radio frequency technology, which is able to show in a second the presence of tumours -- malignant and benign -- in the breast on a computer.
Using radio frequency or microwave technology for breast cancer detection has been proven by researchers in the US, Canada and UK. However, up to now, it can take a few minutes for an image to be produced, and this had to be done in a hospital or specialist care centre.
Now Professor Wu, from the University's School of Electrical and Electronic Engineering, says concerned patients can receive real-time video images in using the radio frequency scanner which would clearly and simply show the presence of a tumour.
Not only is this a quicker and less-intrusive means of testing, it also means women can be tested at GP surgeries, which could help dramatically reduce waiting times and in some cases avoid unnecessary X-ray mammography. The scanner could also be used at home for continuous monitoring of breast health.
The patented real-time radio frequency scanner uses computer tomography and works by using the same technology as a mobile phone, but with only a tiny fraction of its power.
This makes it both safe and low-cost and the electronics can be housed in a case the size of a lunch box for compactness and portability. Other existing systems are much larger.
Breast cancer is the second biggest killer in women, accounting for 8.2% of all cancer deaths. October is National Breast Cancer Awareness month.
The usual way of detecting breast cancer up to now is mammography, which works well for women over the age of 50 and can give results of up to 95% accuracy.
But it is far less effective for younger women. The detection rate could be as low as 60% for women under the age of 50, which accounts for 20% of all breast cancer cases.
At that stage it is even more important get accurate diagnosis. Early diagnosis and treatment could save thousands of lives.
The main difference between the two methods is that mammography works on density, while radio frequency technique works on dielectric contrasts between normal and diseased breast tissues.
In Professor Wu's design, as soon as the breast enters the cup an image appears on screen.
The presence of a tumour or other abnormality will show up in red as the sensor detects the difference in tissue contrasts at radio frequencies. Malignant tissues have higher permittivity and conductivity and therefore appear differently than normal ones to a screen.
Up to 30 images are generated every second, meaning a breast scan could be over in a far shorter time than they are currently.
Professor Wu said: "The system we have is portable and as soon as you lie down you can get a scan -- it's real-time.
"The real-time imaging minimises the chance of missing a breast tumour during scanning.
"Other systems also need to use a liquid or gel as a matching substance, such as in an ultrasound, to work but with our system you don't need that -- it can be done simply in oil, milk, water or even with a bra on.
"Although there is still research to be done, the system has great potential to bring a new way for breast cancer diagnosis.
"This will benefit millions of women in both developed and developing countries bearing in mind that one in nine women may develop breast cancer in their lifetime."
Professor Wu submitted his innovation of the sensor system to the IET Innovation Awards. The technology has been shortlisted in both Electronics and Measurement in Action categories. The winners will be announced in November.

'Microtentacles' on Tumor Cells Appear to Play Role in How Breast Cancer Spreads

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Two breast tumor cells attaching to each other. The red color shows the surface of both tumor cells, while the green color shows how the microtentacles from one cell encircle the neighboring cell
Researchers at the University of Maryland Marlene and Stewart Greenebaum Cancer Center have discovered that "microtentacles," or extensions of the plasma membrane of breast cancer cells, appear to play a key role in how cancers spread to distant locations in the body. Targeting these microtentacles might prove to be a new way to prevent or slow the growth of these secondary cancers, the scientists say.
They report in an article to be published online March 15, 2010, in the journal Oncogene that a protein called "tau" promotes the formation of these microtentacles on breast tumor cells which break away from primary cancers and circulate in the bloodstream. While twisted remnants of tau protein have been seen in the brain tissue of patients with Alzheimer's disease, this is the first report that tau could play a role in tumor metastasis by changing the shape of cancer cells. These tau-induced microtentacles can help the cells reattach to the walls of small blood vessels to create new pockets of cancer.
"Our study demonstrates that tau promotes the creation of microtentacles in breast tumor cells. These microtentacles increase the ability of circulating breast tumor cells to reattach in the small capillaries of the lung, where they can survive until they can seed new cancers," says the senior author, Stuart S. Martin, Ph.D., a researcher at the University of Maryland Greenebaum Cancer Center and associate professor of physiology at the University of Maryland School of Medicine. Michael A. Matrone, Ph.D., is the study's lead author.
Healthy cells are programmed to die -- a process called apoptosis -- after they break off of epithelial layers that cover internal organs in the body. They also can be crushed if they are forced through small capillaries. However, cancer cells are able to survive for weeks, months and even years in the body. Once they are trapped in small blood vessels, the cells can squeeze through microscopic gaps in the vessels' lining and spread to organs such as the brain, lung and liver.
"We hope that through our research, we will be able to identify drugs that will target the growth of these microtentacles and help to stop the spread of the original cancer. Drugs that reduce tau expression may hold potential to inhibit tumor metastasis," Dr. Martin says.
He notes that metastatic cancers are the leading cause of death in people with cancer, but methods used to treat primary tumors have limited success in treating metastatic cancer. In breast cancer, metastases can develop years after primary tumors are first discovered.
Tau is present in a subset of chemotherapy-resistant breast cancers and is also associated with poor prognosis, but Dr. Martin adds, "While tau expression has been studied in breast cancers for contributing to chemotherapy resistance, the protein's role in tumor cells circulating in the bloodstream hasn't been investigated. And that's the focus of our research."
In this recent study, the University of Maryland researchers analyzed breast tumor cells from 102 patients and found that 52 percent had tau in their metastatic tumors and 26 percent (27 patients) showed a significant increase in tau as their cancer progressed. Twenty-two of these patients even had tau in metastatic tumors despite having none in their primary tumors.
Dr. Martin says more studies are needed to determine if tau is a clear predictor of metastasis. Given the complex nature of tumors, there most likely are other factors involved in causing cancers to spread, he says.
"Metastasis is a very major concern for people diagnosed with cancer, and the discovery of these microtentacles and the role that tau plays in their formation is a very exciting development that holds great promise for developing new drugs," says E. Albert Reece, M.D., Ph.D., M.B.A., acting president of the University of Maryland, Baltimore, and dean of the University of Maryland School of Medicine.
The University of Maryland, Baltimore, has filed patents on the microtentacle discoveries of Dr. Martin's lab group and is looking to partner with biopharmaceutical companies on new drug development. The researchers identified these cell extensions while they were studying the effects of two drugs that prevent cell division, or mitosis. Most chemotherapy drugs target cell division, aiming to slow or stop tumor growth.
Dr. Martin says his team found that a popular chemotherapy drug, taxol, actually causes cancer cell microtentacles to grow longer and allows tumor cells to reattach faster, which may have important treatment implications for breast cancer patients. Their studies are continuing.
"We think more research is needed into how chemotherapies that slow down cell division affect metastasis. The timing of giving these drugs can be particularly important. If you treat people with taxol before surgery to shrink the primary tumor, levels of circulating tumor cells go up 1,000 to 10,000 fold, potentially increasing metastasis," he adds.
The study being published in Oncogene was funded by grants from the National Cancer Institute, the USA Medical Research and Materiel Command, and the Flight Attendants Medical Research Institute.

Blocking Inflammation Receptor Kills Breast Cancer Stem Cells, Study Finds

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Scientists at the University of Michigan Comprehensive Cancer Center have uncovered an important link between inflammation and breast cancer stem cells that suggests a new way to target cells that are resistant to current treatments.
The researchers identified a receptor, CXCR1, on the cancer stem cells which triggers growth of stem cells in response to inflammation and tissue damage. A drug originally developed to prevent organ transplant rejection blocks this receptor, killing breast cancer stem cells and preventing their metastasis in mice, according to the study.
Cancer stem cells, the small number of cells that fuel a tumor's growth, are believed to be resistant to current chemotherapies and radiation treatment, which researchers say may be the reason cancer so often returns after treatment.
"Developing treatments to effectively target the cancer stem cell population is essential for improving outcomes. This work suggests a new strategy to target cancer stem cells that can be readily translated into the clinic," says senior study author Max S. Wicha, M.D., Distinguished Professor of Oncology and director of the U-M Comprehensive Cancer Center. Wicha was part of the team that first identified stem cells in breast cancer.
Results of the current study appear online Jan. 4 in the Journal of Clinical Investigation and will appear in the journal's February print issue.
CXCR1 is a receptor for Interleukin-8, or IL-8, a protein produced during chronic inflammation and tissue injury. When tumors are exposed to chemotherapy, the dying cells produce IL-8, which stimulates cancer stem cells to replicate. Addition of the drug repertaxin to chemotherapy specifically targets and kills breast cancer stem cells by blocking CXCR1.
Mice treated with repertaxin or the combination of repertaxin and chemotherapy had dramatically fewer cancer stem cells than those treated with chemotherapy alone. In addition, repertaxin-treated mice developed significantly fewer metastases than mice treated with chemotherapy alone.
"These studies suggest that important links between inflammation, tissue damage and breast cancer may be mediated by cancer stem cells. Furthermore, anti-inflammatory drugs such as repertaxin may provide a means of blocking these interactions, thereby targeting breast cancer stem cells," Wicha says.
Repertaxin has been tested in early phase clinical trials to prevent rejection after organ transplantation. In these studies, side effects seem to be minimal. There are no reports of using repertaxin to treat cancer.
Note to patients: This work was done in cell cultures and mice. Repertaxin is not available to patients at this time and no clinical trials are yet planned.
Breast cancer statisitics: 194,280 Americans will be diagnosed with breast cancer this year and 40,610 will die from the disease, according to the American Cancer Society.
Additional authors: Christophe Ginestier, Suling Liu, Mark Diebel, Hasan Korkaya, Ming Luo, Marty Brown, Jun-Lin Guan, Gabriela Dontu, all from U-M; and Julien Wicinski, Olivier Cabaud, Emmanuelle Charafe-Jauffret, Daniel Birnbaum, all from Universite de la Mediterranee, Marseille, France
Funding: National Institutes of Health, Breast Cancer Foundation, Taubman Institute, Department of Defense, Inserm, Institut Paoli-Calmettes, Institut National du Cancer, Ligue Nationale Contre le Cancer
Disclosure: The University of Michigan has filed for patent protection on this technology, and is currently looking for a commercialization partner to help bring the technology to market.

Natural Compounds in Pomegranates May Prevent Growth of Hormone-Dependent Breast Cancer

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Eating fruit, such as pomegranates, that contain anti-aromatase phytochemicals reduces the incidence of hormone-dependent breast cancer, according to results of a study published in the January issue of Cancer Prevention Research, a journal of the American Association for Cancer Research.

Pomegranate is enriched in a series of compounds known as ellagitannins that, as shown in this study, appear to be responsible for the anti-proliferative effect of the pomegranate.
"Phytochemicals suppress estrogen production that prevents the proliferation of breast cancer cells and the growth of estrogen-responsive tumors," said principal investigator Shiuan Chen, Ph.D., director of the Division of Tumor Cell Biology and co-leader of the Breast Cancer Research Program at City of Hope in Duarte, Calif.
Previous research has shown that pomegranate juice -- punica granatum L -- is high in antioxidant activity, which is generally attributed to the fruit's high polyphenol content. Ellagic acid found in pomegranates inhibits aromatase, an enzyme that converts androgen to estrogen. Aromatase plays a key role in breast carcinogenesis; therefore, the growth of breast cancer is inhibited.
Chen, along with Lynn Adams, Ph.D., a research fellow at Beckman Research Institute of City of Hope, and colleagues, evaluated whether phytochemicals in pomegranates can suppress aromatase and ultimately inhibit cancer growth.
After screening and examining a panel of 10 ellagitannin-derived compounds in pomegranates, the investigators found that those compounds have the potential to prevent estrogen-responsive breast cancers. Urolithin B, which is a metabolite produced from ellagic acid and related compounds, significantly inhibited cell growth.
"We were surprised by our findings," said Chen. "We previously found other fruits, such as grapes, to be capable of the inhibition of aromatase. But, phytochemicals in pomegranates and in grapes are different."
According to Gary Stoner, Ph.D., professor in the Department of Internal Medicine at Ohio State University, additional studies will be needed to confirm the chemopreventive action of Urolithin B against hormone-dependent breast cancer.
"This is an in vitro study in which relatively high levels of ellagitannin compounds were required to demonstrate an anti-proliferative effect on cultured breast cancer cells," said Stoner, who is not associated with this study. "It's not clear that these levels could be achieved in animals or in humans because the ellagitannins are not well absorbed into blood when provided in the diet."
Stoner believes these results are promising enough to suggest that more experiments with pomegranate in animals and humans are warranted.
Powel Brown, M.D., Ph.D., medical oncologist and chairman of the Clinical Cancer Prevention Department at the University of Texas M. D. Anderson Cancer Center, agreed with Stoner's sentiments and said these results are intriguing. He recommended that future studies focus on testing pomegranate juice for its effect on estrogen levels, menopausal symptoms, breast density or even as a cancer preventive agent.
"More research on the individual components and the combination of chemicals is needed to understand the potential risks and benefits of using pomegranate juice or isolated compounds for a health benefit or for cancer prevention," Brown said. "This study does suggest that studies of the ellagitannins from pomegranates should be continued."
Until then, Stoner said people "might consider consuming more pomegranates to protect against cancer development in the breast and perhaps in other tissues and organs."

Flower Power May Reduce Resistance to Breast Cancer Drug Tamoxifen

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Combining tamoxifen, the world's most prescribed breast cancer agent, with a compound found in the flowering plant feverfew may prevent initial or future resistance to the drug, say researchers at Georgetown Lombardi Comprehensive Cancer Center.
The finding, reported online Feb. 12 in The FASEB Journal, provides new insight into the biological roots of that resistance, and also tests a novel way to get around it.
"A solution to tamoxifen resistance is sorely needed, and if a strategy like this can work, it would make a difference in our clinical care of breast cancer," says the study's lead investigator, Robert Clarke, PhD, DSc, a professor of oncology and physiology & biophysics at Lombardi, a part of Georgetown University Medical Center (GUMC). Clarke is also the interim director of GUMC's Biomedical Graduate Research Organization.
Clarke added that the purified research chemical they tested, parthenolide, a derivative of feverfew, is being tested by other scientists as treatment for a variety of cancers, as well as other health conditions. Feverfew has long been a staple of natural medicine, and is particularly known for its effects on headaches and arthritis. Latin for "fever reducer," feverfew is a common garden bush with small daisy-like flowers.
"The chemical clearly has potential, and we ought to be able to figure out fairly quickly if it can help solve tamoxifen's resistance problem," Clarke says.
Tamoxifen is a treatment of choice for breast cancer that is estrogen receptor positive (ER+), meaning that the hormone estrogen drives cancer growth. Most newly diagnosed breast cancers -- about 70 percent -- fall into that category. But about half of these cancers do not initially respond to tamoxifen, which is designed to block the hormone from binding to the cell's protein receptor, and many patients that do respond are at risk for developing resistance and cancer relapse.
In this study, Clarke and a team of researchers set out to study if, as previous research had suggested, tamoxifen resistance is regulated by the protein complex NF-κB (nuclear factor kappa B), which is often found to be over-expressed in ER+ breast cancer. NF-κB is known to help cells survive when damaged. The researchers had earlier discovered that NF-κB is over-expressed in cells that are resistant to tamoxifen, and they had found that resistance to another tamoxifen-like drug, fulvestrant, was controlled by a protein (Bcl2) that is, itself, regulated by NF-κB.
"Our scientific quest was to see if blocking NF-?B affects tamoxifen resistance, and if it does, why?" says Clarke.
They conducted a variety of tests using parthenolide, which has been shown to act on NF-κB. They found that in resistant breast cancer cells, the chemical blocked the activity of NF-κB, making the cells sensitive once again to tamoxifen. They then silenced NF-B in tamoxifen resistant cells, and found that this had the same effect as using parthenolide.
They further found that increased activation of NF-κB can alter sensitivity of tamoxifen by modulating the protein CASP8, which is involved in programmed cell death. That then affects Bcl2, which also helps push a damaged cell to die.
"When you give tamoxifen to a breast cancer cell, that is essentially a pro-death signal, because you are blocking the cell's access to estrogen, and the cell recognizes this is a mortal blow," Clarke says. "Such a damaged cell uses CASP8 and Bcl2 to trigger the cell machinery needed for dying.
"But the cell has ways to counteract the pro-death signal, and one important one is to activate NF-κB, which can control expression of genes necessary for survival," he says. "Now the cell thinks it should be living, not dying."
Because NF-κB controls CASP8 and Bcl2, it can turn those proteins essentially off, Clarke says. "The pro-survival signals override the pro-death signals."
Still, as much as this study advances the understanding of tamoxifen resistance, there is much that is not understood, he adds. "We don't know when NF-κB becomes over-expressed in the transformation of tamoxifen-sensitive to a tamoxifen-resistant breast cancer cells, and we don't know of other adaptations the cell may have made," he says. "It is probably fair to say this is a hideously complex process."
To that end, Clarke cannot predict how many women who try a combination of tamoxifen and parthenolide will benefit. He says the science is much too early to make any recommendations and strongly warns women against adding feverfew supplements to their cancer treatment.
Still, he is hopeful. "Every breast tumor slightly different, but we know many do use NF-κB because excess amounts of the protein are found in these cancers," he says. "That suggests they may be sensitive to targeted approaches that shut down this pro-survival signal."
The study was funded by grants from the U.S. Department of Defense, the Army Medical Research and Material Command, and the National Institutes of Health. The authors disclose no potential financial conflicts.

Mango can arrest growth of certain breast and colon cancer cells

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Mango fruit been found to prevent or stop certain colon and breast cancer cells in the lab.
That's according to a new study by Texas AgriLife Research food scientists, who examined the five varieties most common in the U.S.: Kent, Francine, Ataulfo, Tommy/Atkins and Haden.
Though the mango is an ancient fruit heavily consumed in many parts of the world, little has been known about its health aspects. The National Mango Board commissioned a variety of studies with several U.S. researchers to help determine its nutritional value.
"If you look at what people currently perceive as a superfood, people think of high antioxidant capacity, and mango is not quite there," said Dr. Susanne Talcott, who with her husband, Dr. Steve Talcott, conducted the study on cancer cells. "In comparison with antioxidants in blueberry, acai and pomegranate, it's not even close."
But the team checked mango against cancer cells anyway, and found it prevented or stopped cancer growth in certain breast and colon cell lines, Susanne Talcott noted.
"It has about four to five times less antioxidant capacity than an average wine grape, and it still holds up fairly well in anticancer activity. If you look at it from the physiological and nutritional standpoint, taking everything together, it would be a high-ranking super food," she said. "It would be good to include mangoes as part of the regular diet."
The Talcotts tested mango polyphenol extracts in vitro on colon, breast, lung, leukemia and prostate cancers. Polyphenols are natural substances in plants and are associated with a variety of compounds known to promote good health.
Mango showed some impact on lung, leukemia and prostate cancers but was most effective on the most common breast and colon cancers.
"What we found is that not all cell lines are sensitive to the same extent to an anticancer agent," she said. "But the breast and colon cancer lines underwent apotosis, or programmed cell death. Additionally, we found that when we tested normal colon cells side by side with the colon cancer cells, that the mango polyphenolics did not harm the normal cells."
The duo did further tests on the colon cancer lines because a mango contains both small molecules that are readily absorbed and larger molecules that would not be absorbed and thus remain present in a colon.
"We found the normal cells weren't killed, so mango is not expected to be damaging in the body," she said. "That is a general observation for any natural agent, that they target cancer cells and leave the healthy cells alone, in reasonable concentrations at least."
The Talcotts evaluated polyphenolics, and more specifically gallotannins as being the class of bioactive compounds (responsible for preventing or stopping cancer cells). Tannins are polyphenols that are often bitter or drying and found in such common foods as grape seed, wine and tea.
The study found that the cell cycle, which is the division cells go through, was interrupted. This is crucial information, Suzanne Talcott said, because it indicates a possible mechanism for how the cancer cells are prevented or stopped.
"For cells that may be on the verge of mutating or being damaged, mango polyphenolics prevent this kind of damage," she said.
The Talcotts hope to do a small clinical trial with individuals who have increased inflamation in their intestines with a higher risk for cancer.
"From there, if there is any proven efficacy, then we would do a larger trial to see if there is any clinical relevance," she said.
According to the National Mango Board, based in Winter Park, Fla., most mangoes consumed in the U.S. are produced in Mexico, Ecuador, Peru, Brazil, Guatemala and Haiti. Mangoes are native to southeast Asia and India and are produced in tropical climates. They were introduced to the U.S. in the late 1800s, and a few commercial acres still exist in California and Florida.