Cheese boosts seniors” immune systems

Washington, May 14 (ANI): Cheese can help preserve and enhance the immune system of the elderly by acting as a carrier for probiotic bacteria, say scientists in Finland.

The research, published in FEMS Immunology & Medical Microbiology, reveals that daily consumption of probiotic cheese helps to tackle age-related changes in the immune system.

“The increase in the proportion of aged individuals in modern society makes finding innovative ways to thwart the deterioration of the immune system a priority,” said lead author Dr Fandi Ibrahim from the University of Turku in Finland. “The intake of probiotic bacteria has been reported to enhance the immune response through other products and now we have discovered that cheese can be a carrier of the same bacteria.”

Dr Ibrahim”s team believes that the daily intake of probiotic cheese can tackle the age-related deterioration of the immune system known as immunosenescene.

This deterioration means the body is unable to kill tumour cells and reduces the immune response to vaccinations and infections. Infectious diseases, chronic inflammation disorders and cancer are hallmarks of Immunosenescene.

To tackle immunosenescene the team targeted the gastrointestinal tract, which is the main entry for bacteria cells into the body through food and drink and is also the site where 70 percent of vital immunoglobulin cells are created.

The team asked volunteers aged between 72 and 103, all of which lived in the same care home, to eat one slice of either placebo or probiotic Gouda cheese with their breakfast for four weeks. Blood tests where then carried out to discover the effect of probiotic bacteria contained within the cheese on the immune system.

The results revealed a clear enhancement of natural and acquired immunity through the activation of NK blood cells and an increase in phagocytic activity.

“The aim of our study was to see if specific probiotic bacteria in cheese would have immune enhancing effects on healthy older individuals in a nursing home setting,” concluded Ibrahim. “We have demonstrated that the regular intake of probiotic cheese can help to boost the immune system and that including it in a regular diet may help to improve an elderly person”s immune response to external challenges.” (ANI)

Erectile dysfunction drug could enhance delivery of herceptin to brain tumours

Washington, May 8 (ANI): A drug currently approved to treat erectile dysfunction could significantly improve the delivery of the anti-cancer drug Herceptin to certain hard-to-treat brain tumours, according to a new study at Cedars-Sinai”s Maxine Dunitz Neurosurgical Institute.

The research could help doctors improve treatments for lung and breast cancers that have metastasized to the brain.

Even if a cancer is susceptible to drugs, these drugs must penetrate the “blood-brain barrier” if they”re to treat cancer that”s metastasised to the brain.

“Mother Nature created this barrier to protect our brains from dangerous substances, but here we need to get through the barrier to deliver the drugs, and that”s a problem,” says study author Dr. Julia Y. Ljubimova.

Dr. Keith Black, lead research scientist on this project, has studied the blood-brain barrier for about two decades.

Research conducted by his team found that the erectile dysfunction drugs sildenafil (Viagra) and vardenafil (Levitra), which inhibit the enzyme phosphodiesterase 5 (PDE5), could increase the permeability of the blood-brain tumour barrier and boost the effectiveness of the chemotherapy drug doxorubicin.

“No matter how effective against cancer a chemotherapeutic agent may be, it can have little impact on brain tumours if it cannot cross the blood-brain tumour barrier. As we find new drugs that are able to target these tumour cells, it is imperative that we develop better ways to enable the medications to reach their targets,” he said.

In the current study, the researchers examined whether PDE5 inhibitors might also increase the blood-brain tumour barrier”s permeability to Herceptin— a monoclonal antibody used to treat lung and breast tumours that are positive for HER2/neu.

Herceptin is a large molecule that does not easily cross the blood-brain tumour barrier, a limitation that severely reduces its effectiveness at treating brain metastases.

The researchers first measured vardenafil”s effects on the permeability of the blood-brain tumour barrier.

Using a mouse model, the scientists showed that vardenafil led to a two-fold increase in the amount of Herceptin that reached brain metastases of lung and breast cancers.

Next, they examined whether this increase in blood-brain barrier permeability improved Herceptin”s effectiveness at treating these brain metastases by giving mice vardenafil in tandem with Herceptin.

The results showed that the combination of vardenafil plus Herceptin boosted mean survival by 20 percent, compared to Herceptin alone (72+/-18 days versus 59+/-9 days).

The study was published in the journal PLoS ONE. (ANI)

Hormone therapies ”up breast cancer metastasis risk in post-menopausal women”

Washington, May 7 (ANI): A University of Missouri study has found that hormone therapies not just increase the risk of breast cancer in post-menopausal women, they can also increase the chance of the cancer metastasising.

After menopause, women take hormone therapies, which are often a combination of estrogen and progestin, to replace hormones lost from inactive ovaries.

Progestin is a hormone that is used to counteract the potentially negative effects of estrogen therapy on the uterus.

Previous studies have shown that estrogen and progestin in hormone therapies increase the risk of breast cancer in post-menopausal women.

Now, the new study has demonstrated that progestins can also increase the chance of the cancer metastasizing, or spreading to the lymph nodes.

“In our study, we found that progestins increase the number of blood vessels that are responsible for transporting existing cancer cells,” said Salman Hyder, the Zalk Endowed Professor in Tumour Angiogenesis and professor of biomedical sciences in the College of Veterinary Medicine and the Dalton Cardiovascular Research Center.

“The more the blood vessels increase, the higher the chance of cancer cell metastasizing. Progestins could even be more harmful to women who have functionally abnormal p53, a protein that acts as a tumour suppressor. In the absence of p53, progestins increase the release of a protein from tumour cells that allows formation of new blood vessels within tumours.”

In the study, researchers compared the effects of several types of commonly used progestins on breast cancer tumours in an animal model. Researchers found that all types of progestin tested act in the same way and increased the risk of metastasis.

Also, results showed that estrogen and progestin acted the same way whether taken together or separately. Although Hyder said that the study was independent of whether or not the ovaries were intact, it”s still unclear whether progestins have the same effects in pre-menopausal women.

“Especially if there”s a family history of breast cancer, it”s advisable not to take progestins. It”s a difficult call that must be made on an individual basis by a physician,” Hyder said.

“The next step for this research is finding a type of progestin that does not cause tumor progression but still protects the uterus. Also, we”re trying to see if it”s possible to give patients something in addition to estrogen and progestin that can protect the breast,” Hyder added.

The study has been accepted for publication in the Journal Menopause. (ANI)

Rabbit virus may harbour colorectal cancer cure

Wellington, May 5 (ANI): A new “highly promising” vaccine therapy, which owes its origin to rabbit calicivirus disease (RCD), could offer hope for colorectal cancer sufferers, according to University of Otago researchers.

The therapy uses harmless viral shells derived from RCD, also known as rabbit haemorrhagic disease, to deliver immunising tumour proteins.

And according to researchers, the same approach could also be applied to a wide range of human cancers.

Sarah Young, an immunologist in the university””s department of microbiology and immunology, told the Otago Daily Times that the cancer-related research, involving virus-like particles (VLP), was very promising.

“This therapy is like gold in our hands. It””s worked as well if not better than any other therapy I””ve ever seen,” Stuff.co.nz quoted her as saying.

Mice with induced tumours usually lived no longer than 40 days, but after a single dose of the VLP vaccine, 60 percent of them lived for 80 days or more, found the researchers.

About 80 percent of mice receiving a preventive dose lived for 80 days or more after a tumour was induced.

Ethical approval has been granted to conduct laboratory tests this year involving cells removed from the body, to see if the VLP system can induce an enhanced immune response in human cells and human clinical trials could be held late next year.

The new vaccine approach offered potentially significant advantages over some forms of traditional cancer therapy, such as chemotherapy.

Inducing the immune system to attack only tumour cells was a much more selective approach. (ANI)

Breast milk may help beat cancer

Washington, Apr 20 (ANI): Researchers at Lund University and the University of Gothenburg, Sweden claim that a substance found in breast milk can kill cancer cells.

Although the special substance, known as HAMLET (Human Alpha-lactalbumin Made LEthal to Tumour cells), was discovered in breast milk several years ago, it is only now that it has been possible to test it on humans.

Patients with cancer of the bladder who were treated with the substance excreted dead cancer cells in their urine after each treatment, which has given rise to hopes that it can be developed into medication for cancer care in the future.

Lab experiments have shown that HAMLET kills 40 different types of cancer, and the researchers are now going on to study its effect on skin cancer, tumours in the mucous membranes and brain tumours. Importantly, HAMLET kills only cancer cells and does not affect healthy cells. (ANI)

New discovery to help diabetics with slow-to-heal wounds

Washington, Apr 17 (ANI): With a new discovery about wound-healing process, scientists could offer better treatments to diabetics and other patients who have wounds that take time to heal.

Loyola University Health System researchers found that certain immune system cells slow the wound-healing process.

Thus, it might be possible to improve healing by inactivating these immune system cells, said Dr. Elizabeth Kovacs, who heads the laboratory team that made the discovery.

In the study, the immune system cells that impeded the healing process are called natural killer T (NKT) cells.

NKT cells perform beneficial functions such as killing tumour cells and virus-infected cells.

However, researchers discovered that NKT cells also migrate to wound sites and impede the healing process.

The researchers used an animal model to examine the effects of NKT cells on healing.

Healing was significantly slower in normal mice that had NKT cells than it was in a special breed of mice that lacked NKT cells.

“We demonstrated that early wound closure was accelerated in the absence of NKT cells. Importantly, we also made the novel observation that NKT cells themselves are a constituent of the early wound inflammatory infiltrate,” wrote the researchers.

Certain conditions, such as diabetes and infections, can slow or prevent wounds from healing.

Researchers don”t know how NKT cells slow healing, but they believe it is possible to inactivate NKT cells using an antibody.

They are testing this prediction in a follow-up study.

The findings are reported online, in advance of print, in the Journal of Surgical Research. (ANI)

Molecular signature may tell which cancer patients will respond to therapy

London, September 7 (ANI): American scientists say that a molecular signature that that helps account for the aggressive behaviour of a variety of cancers-such as pancreatic, breast and melanoma-may also help identify patients who are likely to respond to a particular anti-cancer drug.

Researchers at the Moores Cancer Center at the University of California-San Diego (UCSD) say that their findings may lead to a personalized approach to treatment for a variety of solid tumours that are currently resistant to therapies.

In a study, they have found that a receptor sitting on the surface of certain aggressive tumour cells can activate a key enzyme, src-kinase, which helps tumour cells to become more aggressive in the body.

Writing in their study report, the researchers have pointed out that this enzyme is the target of the anticancer drug dasatinib, which blocks its activity and is currently approved for treating chronic myelogenous leukemia (CML).

They further state that the scientists the presence of the receptor – a protein called integrin alpha-v beta-3 – on some of the more common solid tumors such as breast, colon, lung and pancreas could help identify individuals with many other types of cancer that are also likely to respond to the drug.

“These results could enable us to identify the subpopulation of cancer patients who are likely to respond to treatment with dasatinib,” Nature magazine quoted Dr. David Cheresh, professor and vice chair of pathology at the UC San Diego School of Medicine and the Moores UCSD Cancer Center, who led the work, as saying.

“Rather than treat all patients with a given tumor type the same way, by identifying a specific molecular signature consisting of the receptor and its activated enzyme, we can customize the treatment in such a way that we impact the patients most likely to be sensitive to a drug,” he added.

During the study, the researchers compared the growth properties of pancreatic and breast cancer cells that expressed the alpha-v beta-3 receptor with those that did not.

Their effort led to the discovery of a molecular pathway that accounted for the increased malignancy.

“Once we identified the pathway, we immediately realized that the drug dasatinib, which targets this pathway, would be a logical choice to use against these cancers,” Cheresh said.

Experimenting on a pre-clinical model of pancreatic cancer, the researchers have confirmed that tumour cells with the receptor responded to the drug, while those not expressing receptors did not.

Cheresh pointed to pancreatic cancer tumours, approximately 60 percent of which carry the marker on the tumour cell surface.

“We would argue that pancreatic cancer patients with alpha-v beta-3 would respond to dasatinib,” he said.

According to him, tumours that lack the marker appear to be resistant to the drug.

“We discovered an unexpected pathway that accounts for increased malignancy in a population of some of the most dangerous cancers,” he said, noting that the marker could be identified by a biopsy.

“There are features of the findings that allow us to implicate dasatinib not just for a single tumour type, but for all tumours with the malignant signature,” he added.

Dr. Barbara Parker, medical director of oncology services at the Moores UCSD Cancer Center, said: “These observations suggest a strategy for testing the effectiveness of dasatinib in breast cancer patients who are positive for the alpha-v beta-3 receptor.”

A research article on the study has been published in the online edition of the journal Nature Medicine. (ANI)

How sugar ‘feeds’ cancer

Washington, August 18 (ANI): Gaining fresh insights into the notion that sugar “feeds” cancer, researchers at Huntsman Cancer Institute at the University of Utah may have moved a step closer to realising potential treatments to stop tumour growth.

“It’s been known since 1923 that tumour cells use a lot more glucose than normal cells. Our research helps show how this process takes place, and how it might be stopped to control tumour growth,” says Dr. Don Ayer, a Huntsman Cancer Institute investigator and professor in the Department of Oncological Sciences at the University of Utah.

The researchers point out that during both normal and cancerous cell growth, a cellular process takes place that involves both glucose (sugar) and glutamine (an amino acid).

Glucose and glutamine are both essential for cell growth, they say.

While it was long assumed they operated independently, Ayer’s research shows they are inter-dependent.

He has found that glucose utilization is stopped when glutamine availability is restricted.

“Essentially, if you don’t have glutamine, the cell is short circuited due to a lack of glucose, which halts the growth of the tumour cell” he says.

Dr. Mohan Kaadige, a postdoctoral fellow in Ayer’s lab, focused on a protein called MondoA, responsible for turning genes on and off, during the study.

In the presence of glutamine, MondoA blocks the expression of a gene called TXNIP. TXNIP is thought to be a tumour suppressor, but when it’s blocked by MondoA , it allows cells to take up glucose, which in turn drives tumor growth.

Ayer believes that his team’s work may lead to new drugs that would target glutamine utilization, or target MondoA or TXNIP.

He says that the next step in his research is to develop animal models to test his ideas about how MondoA and TXNIP control cell growth.

“If we can understand that, we can break the cycle of glucose utilization which could be beneficial in the treatment of cancer,” he says.

A research article describing the study has been published in the journal Proceedings of the National Academy of Sciences. (ANI)

Novel targeted therapy shows promise to eliminate leukaemia stem cells

Washington, July 3 (ANI): A piece of research has shown that it is possible to eliminate stem cells related to human acute myeloid leukemia (AML), a notoriously treatment-resistant blood cancer, using a new targeted therapy.

Associate Professor Richard Lock, from the Children’s Cancer Institute Australia and the University of New South Wales, has revealed that the new therapeutic approach has been found to selectively attack human cancer cells grown in the lab as well as in animal models of leukaemia.

AML is a cancer of the white blood cells that has an extremely poor prognosis and does not respond well to conventional chemotherapy.

“The cellular and molecular basis for this dismal picture is unclear. However, previous research has suggested that leukaemia stem cells (LSCs) may lie at the heart of post-treatment relapse and chemoresistance,” says Lock.

LSCs are cells that can initiate AML and are critical for its long-term growth.

Lock and his colleagues exploited the fact that the molecule CD123 is expressed at very high levels on LSCs but not on normal blood cells.

The researchers created a therapeutic antibody that recognized and bound to CD123, hoping that the antibody would selectively interfere with AML-LSC survival.

When AML-LSCs from human patients were transplanted into mice treated with the antibody, called 7G3, cytokine signalling in the tumour cells was blocked.

The research team also observed that 7G3 impaired migration of the AML-LSCs to bone marrow, and activated the innate immune system of the host mouse to destroy the AML-LSCs.

They say that, overall, treatment with 7G3 substantially improved mouse survival when compared with control groups.

Lock and his colleagues are currently using a CD123-targeting antibody in phase 1 clinical trials of advanced AML. They say that there are no signs of treatment-related toxicity.

These results hold substantial promise for future cancer therapeutics.

“The recent characterization of defined populations of cancer stem cells in a range of human malignancies, as well as their relative resistance to conventional chemotherapy and radiotherapy, supports the broad applicability of our approach and provides rationale for the progression of AML-LSC-targeted therapeutics from preclinical evaluation to clinical trials,” concludes Associate Professor Lock.

A research article on the study has been published in the journal Cell Stem Cell. (ANI)

New ‘minicell therapy’ to crash cancer resistance

London, June 29 (ANI): Aussie scientists have developed a new therapy that uses minicells to deliver cancer drugs, in order to prevent resistance in cancer cells.

The researchers are confident that the breakthrough could pave way for cheaper cancer treatments with fewer side effects.

While experimenting on mice, the researchers used minicells to deliver cancer drugs to resistant tumours.

The minicells were made from bacteria and contained pieces of genetic material, known as short interference RNA (siRNA), which knockout or ‘silence’ the drug-resistant genes of tumours.

After a few days, the researchers injected another dose of minicells filled with chemotherapy drugs, which the tumour was previously resistant to.

Dr Himanshu Brahmbhatt, molecular biologist and joint director of the biotechnology company Engeneic, said that cancer cells have an inbuilt mechanism to develop drug resistance over time.

“(Drug resistance) is one of our biggest killers in terms of cancer therapy,” Nature magazine quoted him as saying.

He claimed that silencing the genes of the drug-resistant tumour cell makes the cancers sensitive to the chemotherapy again.

Earlier, it was believed that siRNA could pass through cells membranes due to their size, but Brahmbhatt says that the new study has shown that this isn’t necessarily the case.

“Bacterial membranes might be quite different because they have protein channels (in their membrane) through which siRNA’s can enter (the minicell),” he said.

The outer surface of the minicell membrane is not only packed with gene silencing siRNA, but is also coated with antibodies, which lock onto (antigen) receptors on the tumour cells.

“The cancer cell then swallows the entire minicell,” said Brahmbhatt.

He added that once the minicell is inside the cancer cell, its breaks down and the siRNA or the drug floods the interior of the tumour cell.

“That’s why we haven’t seen any toxic side effects because this is intra-cellular delivery,” he said.

The study has shown that the combined minicell therapy can inhibit the growth of drug-resistant tumour xenographs, artificially manufactured tumours, for up to four months.

The findings appear in the online edition of Nature Biotechnology. (ANI)

Protein that controls conversion of normal cells into cancer cells identified

Washington, June 26 (ANI): A protein called STAT3 has a major role to play in the conversion of normal cells into cancerous cells, according to a study.

Led by Dr. David E. Levy, a professor of pathology and microbiology at NYU Langone Medical Centre, the study found that STAT3 not only plays a part in the cell nucleus regulating gene expression, but is also present in mitochondria and regulates the activity of the electron transport chain in tumour cells.

Mitochondria are the basic energy-producing organelles of the cell, and are known to be critical for tumour cell metabolism.

“These results open the possibility that inhibiting the mitochondrial function of STAT3 could be a promising cancer therapy in the future.

By knowing this mitrochondrial function is critical, it may be possible to design therapeutic strategies that specifically target this function while sparing the other functions of the protein, such as its ability to turn genes on. Therefore, we would hope that inhibitors could be developed that would be highly specific for cancer cells,” added Levy.

STAT3, which stands for “signal transducer and activators of transcription”, is a protein that was discovered as a regulator of gene expression.

Its only function was thought to be to turn genes on in the cell nucleus, particularly when the cells have been exposed to events that require an immune response.

However, it was found to mediate many critical steps in the response to infection.

The researchers in the current study have been studying STAT3 since the mid 1990s, when they first cloned its gene.

The current results were obtained from experiments that examined tumours caused by the Ras oncogene, which causes many human cancers.

“Future experiments will need to determine if a similar mitochondrial role for STAT3 is critical for other types of cancer as well. We’ll also need a better understanding of the biochemical basis for the function of STAT3. For instance, we are trying to find out what STAT3 does in mitochondria, what enzymes and processes it regulates and how these processes differ in tumors compared to normal cells,” said Levy.

The study has been published in the journal Science. (ANI)

Cottonseed-based drug may help treat severe brain cancer

Washington, May 29 (ANI): Researchers at the University of Alabama at Birmingham (UAB) say that an experimental drug derived from cottonseeds appears to be efficacious in treating the recurrence of glioblastoma multiforme, which is considered to be the most lethal brain cancer.

The researchers came to this conclusion following the results of a Phase II clinical trial of AT-101, a pill manufactured from a potent compound in cottonseeds that overcomes the abnormal growth patterns of tumour cells.

Glioblastomas are more common in adults, and are considered fast-growing brain tumours that are very difficult to treat.

Research leader Dr. John Fiveash, an associate professor in the UAB Department of Radiation Oncology, said that the cottonseed-based agent was found to halt the cancer’s progression in many of the 56 patients.

He revealed that despite undergoing other treatments, including surgery, chemotherapy and radiation, the trial patients’ brain cancer had begun to grow again prior to starting AT-101 treatments.

The trial-monitored patients took only AT-101 daily for three out of four weeks.

“After getting this drug some of these patients went many months without any new growth in their tumours. We are able to do that with a well-tolerated oral medication, and that is a major benefit,” Fiveash said.

He believes that the drug would likely work best in combination with radiation and chemotherapy to boost the cancer-fighting properties of those treatments.

Fiveash and his colleagues are also trying to determine which patients are most likely to benefit from AT-101.

The initial results of the drug trial would be presented on May 30, during the poster discussion of central nervous system tumours at the American Society for Clinical Oncology annual meeting in Orlando, Florida. (ANI)

Experimental drug shows promise in treating head, neck cancers

Washington, April 29 (ANI): An anti-cancer compound studied for treating blood cancers may also help in treating cancers of the head and neck, say researchers at Albert Einstein College of Medicine of Yeshiva University.

The study involved a new class of chemotherapy agents known as histone deacetylase (HDAC) inhibitors, which affect the availability of genes that are transcribed and translated into proteins.

In many types of cancer, out-of-control cell growth results from certain genes that are either too active or not active enough in producing proteins.

HDAC inhibitors appear to combat cancer by restoring the normal expression of key regulatory genes that control cell growth and survival.

The researchers focused on a particular HDAC inhibitor known as LBH589 that has already shown some success in clinical trials involving people with cancers of the blood.

The researchers found that LBH589 succeeded in killing tumour cells that had been removed from head and neck cancer patients and grown in the laboratory.

“This report shows that an HDAC inhibitor is effective on head and neck cancer cell lines, and that is the first step toward use in humans,” said Richard Smith, M.D., the lead clinician involved in the study.

The researchers also identified a set of genes whose expression levels change in response to the HDAC inhibitors-a finding that may help doctors identify patients most likely to respond to the drug.

Plans call for testing LBH589 on head and neck tumour cells from more patients so that the set of genes that respond to the drug can be more firmly established.

Michael Prystowsky, M.D., Ph.D., chair and professor of pathology at Einstein and co-author of the study, said: “We are performing studies in mice to confirm these laboratory results, which hopefully will progress to human clinical trials of LBH589 for the treatment of head and neck cancer,” said

The study is reported in the April 28th online edition of the Journal of Pathology. (ANI)

Drug-combo could prevent pancreatic cancer recurrence

Washington, Apr 20 (ANI): In a study, led by an Indian-origin scientist, researchers have found a combination therapy, which could reduce cancer stem cells and stop the growth pancreatic cancer-one of the deadliest cancers.

Rajesh Kumar N.V., Ph.D., a faculty member at the Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins University, led the study.

He said that a combination therapy using tigatuzumab, a novel humanized death receptor-5 (DR-5) agonist antibody, along with gemcitabine, could result in reducing pancreatic cancer stem cells to achieve tumour remission and prevent tumour recurrence.

“Many advanced cancers, including pancreatic cancer, recur and result in patient death despite the use of chemotherapeutic and radiation modalities that initially lead to therapeutic responses,” said Kumar.

He added: “A growing body of evidence supports the concept that cancer stem cells are the seeds of the most clinically deadly form of therapy-resistant human cancers. Emerging studies show that cancer stem cells are indeed more resistant to therapy than other cancer cells and might be the reason why conventional chemotherapy, while reducing tumor size, does not result in long-term cures.”

For the study, the researchers examined the cancer stem cells in ten patient-derived tumours implanted in laboratory mice.

It was found that DR-5 is enriched in cancer stem cells compared to non-stem cell tumour populations.

The mice either received tigatuzumab alone; gemcitabine, the current clinical treatment for pancreatic cancer; or a combination of the two agents.

And it was discovered that treatment with gemcitabine alone reduced tumour size, but the tumour cells that remained were rich in pancreatic cancer stem cells. In nearly all cases, the tumours returned.

On the other hand, treatment with gemcitabine and tigatuzumab reduced pancreatic cancer stem cells, caused tumour remission, and significantly increased time-to-tumour progression in 50 percent of treated cases from a median of 54 days to 103 days.

The researchers claimed that targeting cancer-sustaining pancreatic cancer stem cells will be of paramount significance as there are few effective therapies for pancreatic cancer and most of the patients die within the first year of diagnosis.

“Clinically, this discovery could transform the way in which pancreatic cancer is treated and contribute towards making pancreatic cancer a more manageable disease,” said Kumar.

Results of the study will be presented at the American Association for Cancer Research 100th Annual Meeting 2009. (ANI)

Active component of marijuana may fight brain cancer

Washington, April 2 (ANI): Cannabinoids such as the main active component of marijuana (THC) have anticancer effects on human brain cancer cells, a new study has found.

In the study, Guillermo Velasco and colleagues at Complutense University, Spain, found that THC induced the death of various human brain cancer cell lines and primary cultured human brain cancer cells by a process known as autophagy.

Consistent with the in vitro data, administration of THC to mice with human tumours decreased tumour growth and induced the tumour cells to undergo autophagy.

As analysis of tumours from two patients with recurrent glioblastoma multiforme (a highly aggressive brain tumour) receiving intracranial THC administration showed signs of autophagy.

The researchers suggest that cannabinoid administration may provide a new approach to targeting human cancers. (ANI)

Scientists make new drug agent that kills multiple enzymes in cancer pathway

Washington, March 26 (ANI): An international team of researchers have come up with a new anti-cancer agent that is about 200 times more active in killing cancer cells than other drugs used in clinical trials to date.

Led by University of Illinois scientists, the team of 24 researchers have revealed that the new agent belongs to a class of drugs called bisphosphonates.

According to them, such compounds were originally developed to treat osteoporosis and other bone diseases, but were recently found to also have potent anti-cancer and immune boosting properties.

Emphasizing that nearly a third of all human cancers involve a mutation in a gene called Ras, which causes cell signalling to go awry, the researchers highlight the fact that efforts to design potential drugs to prevent such irregularity have met with limited successful.

Given that bisphosphonates act on enzymes called FPPS and GGPPS, which are upstream of Ras in the cell survival pathway, the researchers say that inhibiting these enzymes seems to be a more effective strategy for killing cancer cells.

The scientists used the bisphosphonate drug zoledronate in combination with hormone therapy in a recent clinical trial, and found it to significantly reduce the recurrence of breast cancer in pre-menopausal women with oestrogen-receptor-positive breast cancer.

Similar results were reported previously for hormone-refractory prostate cancer, they say.

However, zoledronate quickly binds to bone, reducing its efficacy in other tissues.

“We’re trying to develop bisphosphonates that will be very active but won’t bind to the bone, because if they bind to the bone they’re not going to go to breast, lung or other tissues,” said lead researcher Eric Oldfield, a professor of Chemistry at the University of Illinois.

“The new drugs are about 200 times more effective than the drugs used in recent clinical trials at killing tumour cells and in activating gamma delta T-cells to kill tumour cells. They also prevent tumour progression in mice much better than do existing bisphosphonate molecules,” Oldfield said.

The study appears in the Journal of the American Chemical Society. (ANI)

Lab-on-a-Chip may help study how cancer cells detach from neighbouring tissue to spread disease

London, March 19 (ANI): Johns Hopkins engineers say that they have developed a new lab-on-a-chip that can lead to better cancer therapies.

The researchers say that their invention may help figure out how cancer cells break free from neighbouring tissue, an “escape” that can spread the disease to other parts of the body.

“Studying cell detachment at the subcellular level is critical to understanding the way cancer cells metastasize. Development of scientific methods to study cell detachment may guide us to prevent, limit or slow down the deadly spreading of cancer cells,” Nature magazine quoted principal investigator Peter Searson, Reynolds Professor of Materials Science and Engineering, as saying.

He points out that cancer that starts in the breast, for example, sometimes spreads to the lungs because tumour cells detach and travel through the bloodstream to settle in other tissues.

He further says that scientists have learnt much about how cancer cells attach to these surfaces, but very little is known as to how such insidious cells detach because no one had created a simple way to study the process.

Searson hopes that the new lab-on-a-chip may solve this problem by helping scientists discover exactly how cancer cells spread.

Describing the new device, he has revealed that it boasts an array of gold lines on a glass slide.

He says that molecules promoting the formation of cell attachments are tethered to the gold lines like balloons tied to string. A cell is placed on the chip, atop the molecules.

According to him, the cell spreads across several of the gold lines, forming attachments to the surface of the chip with help from the molecules.

Searson says that the tethered molecules are released from one of the lines by a chemical reaction, specifically by “electrochemical reduction”.

Where the molecules are detached, according to the researcher, that portion of the cell loses its grip on the surface of the chip.

The researchers have filmed a “tail snap” under a microscope showing this segment of the cell pausing for a moment, and then contracting forcefully toward its other end, still attached to the chip.

“It’s very dramatic. The cell stretches way, way out across the chip and then, on command, the tail snaps toward the body of the cell,” says Denis Wirtz, a Johns Hopkins professor of chemical and biomolecular engineering and co-author of the paper.

The researchers say that cells survive this programmed-release process, and can be tested again and again.

The team say that if they have their way, their experiments will one day give them a tool to differentiate between cancerous and non-cancerous cells.

A research article describing the invention has been published in the journal Nature Methods. (ANI)

Instant ‘vaccine’ turns mouse antibodies into potent cancer killers

London, March 12 (ANI): Scientists in California have announced the creation of molecules that transform mouse antibodies into potent cancer killers.

Carlos Barbas, of the Scripps Research Institute in La Jolla, says that the dumb-bell shaped “adaptor” molecules bind mouse antibodies to proteins on the surface of disease-causing agents, redirecting the antibodies’ killing focus.

In a previous study, the researchers attached these molecules to a single kind of antibody in the lab, and injected them into the mouse to kill tumour cells.

In the current study, they have shown that the synthetic molecules can bind many kinds of antibodies to cancer cells inside mice, and reduce the size of implanted human tumours.

Revealing their findings in the Proceedings of the National Academy of Sciences, the researchers said that the colon tumours had shrunk by up to 90 per cent, and melanomas by 78 per cent, four weeks after they injected the molecules into the lab mice.

Barbas believes that it may be possible to customise the molecules to bind antibodies to HIV, to fight flu and malaria, or to protect against bio-terror agents.

“This is a highly ingenious way to induce an instant ‘vaccine effect’,” New Scientist magazine quoted Peter Palese, who studies RNA viruses at the Mount Sinai School of Medicine in New York, as saying.

However, given that the adaptors only stay attached for three to four days, the researchers say that any such treatment would require booster shots to be effective. (ANI)

Twin nanoparticle shows greater success at killing breast cancer cells

Washington, Mar 11 (ANI): The side effects of medications given to breast cancer patients during chemotherapy occur because drugs released into the body target healthy cells as well as tumour cells. Now, Brown University researchers have developed a new way to deliver cancer-fighting drugs directly to the tumour cells.

They have created a twin nanoparticle that specifically targets the Her-2-positive tumour cell, a type of malignant cell that affects up to 30 percent of breast cancer patients.

The combination nanoparticle binds to the Her-2 tumor cell and unloads the cancer-fighting drug cisplatin directly into the infected cell.

The result is greater success at killing the cancer while minimizing the anti-cancer drug’s side effects.

“Like a missile, you don’t want the anti-cancer drugs to explode everywhere. You want it to target the tumour cells and not the healthy ones,” said Shouheng Sun, a chemistry professor at Brown University and an author on the paper published online in The Journal of the American Chemical Society.

The researchers created the twin nanoparticle by binding one gold (Au) nanoparticle with an iron-oxide (Fe3O4) nanoparticle. On one end, they attached a synthetic protein antibody to the iron-oxide nanoparticle. On the other end, they attached cisplatin to the gold nanoparticle.

Visually, the whole contraption looks like an elongated dumbbell, but it may be better to think of it as a vehicle, equipped with a very good GPS system, that is ferrying a very important passenger.

In this case, the GPS comes from the iron-oxide nanoparticle, which homes in on a Her-2 breast-cancer cell like a guided missile. The attached antibody is critical, because it binds to the antigen, a protein located on the surface on the malignant cell.

Put another way, the nanoparticle vehicle ‘docks’ on the tumour cell when the antibody and the antigen become connected. Once docked, the vehicle unloads its “passenger,” the cisplatin, into the malignant cell.

In a neat twist, the Brown-led team used a pH-sensitive covalent bond to connect the gold nanoparticle with the cisplatin to ensure that the drug was not released into the body but remained attached to the nanoparticle until it was time for it to be released into the malignant cell.

In laboratory experiemnts, the gold-iron oxide nanoparticle combination successfully targeted the cancer cells and released the anti-cancer drugs into the malignant cells, killing the cells in up to 80 percent of cases. (ANI)

Novel tool to control growing blood vessels

Washington, Feb 22 (ANI): As part of a major achievement in tumour research, scientists at Uppsala University have developed a new tool that can study signals in body that control the generation of blood vessels.

The findings of the study can help in learning which signals in the body attract or repel blood vessels that can further improve the knowledge in tumour research.

The tool is a tiny cell cultivation chamber of silicon plastic in which researchers can cultivate blood-vessel-rich tissue and simultaneously create targeted signals that instruct the vessels to go in a certain direction.

Angiogenesis is the process in the body that forms new blood cells, a process that is vital for life but can also be fatal in the worst case.

Usually, angiogenesis is desirable, for instance, in connection with wound healing, when new tissue needs to be grown. But, undesirable angiogenesis often occurs in connection with tumour growth.

By making use of the newly generated blood vessels in the vicinity of the tumour, tumour cells receive nourishment and oxygen, which creates the conditions for tumour growth.

Thus, one way to limit tumour growth may be to counteract the new formation of blood vessels in the tumour, thereby cutting off the supply of nourishment and oxygen to the diseased area.

Thus, scientists Irmeli Berkefors and Johan Kreuger, focussed their study on understanding the signals that control both normal and pathological angiogenesis.

For this, it is important to construct experimental model systems in which they can study how concentration gradients of various signal proteins affect the direction in which a vessel grows.

“Our new method enables us to recreate and study gradients that control how blood vessels grow in the body. This is something of a research breakthrough. Now we can systematically evaluate newly identified signals that we hope can ultimately be used to control angiogenesis,” said Johan Kreuger.

The method can also be used to gain new knowledge regarding how tumour cells and nerve cells grow and move toward gradients of signal proteins.

The study is published in the new issue of Lab on a Chip. (ANI)