Tag Archive | "Cancer"

Cancer cells ‘cheat suicide call’

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Cancer cells cheat death by reversing a process which causes normal cells to commit suicide at the end of their natural life, scientists have shown.

They showed cancer cells were able to recover even after exposure to a chemical cocktail which triggers suicide in normal cells.

The ability may help cancer cells to block the effect of chemotherapy drugs.

The study, by the Chinese University of Hong Kong, appears in the British Journal of Cancer.

Programmed cell suicide - or apoptosis - plays a key role in keeping the body healthy, by ridding it of damaged or defective cells.

If these cells are not destroyed, then they can may continue to divide, developing into a tumour.

The researchers treated human cervical, skin, liver and breast cancer cells each with three different chemicals - jasplakinolide, staurosporine and ethanol - which triggers apoptosis in normal cells.

They wanted to see if cancer cells could survive once they have passed the point of no return for normal cell death.

The researchers found the cancer cells recovered once the chemical cocktail had been removed - even after the cells had passed normal critical checkpoints.

Changing shape

When the chemicals were removed, the cancer cells regained their shape, function and continued to divide.

They only lost the ability to recover once the nucleus at the very heart of the cell containing key genetic material had started to disintegrate - an event right at the end of the normal cell suicide process.

Researcher Professor Ming-Chiu Fung said the study suggested that cancer cells could use this ability to survive assault by chemotherapy drugs.

He said the discovery could potentially help the development of new, more effective anti-cancer drugs.

Dr Lesley Walker, of the charity Cancer Research UK, said: “This eye-opening discovery has created an entire map of new routes to explore in the search for new therapy targets.

“It is an intriguing advance and one that we hope will play a useful part in our efforts to beat cancer.”

Source: BBC NEWS

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NICE issues new guidelines for better access to life-extending treatments for terminally ill patients

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The UK National Institute for Health and Clinical Excellence issued new guidelines to improve access to life-extending drug therapies for individuals facing terminal illnesses, under certain circumstances. NICE ruled that the current threshold at which a drug is deemed cost-effective can now be extended for patients with rare terminal illnesses, including certain types of cancer.

For a product to be approved under the new rules, the drug should provide evidence of extended survival by at least three months for patients who have fewer than two years to live, NICE stated, specifying that the medication must also be licensed for treating a condition affecting less than 7000 patients in the UK. The agency indicated that it will improve the appraisal process in order to have guidance ready between three and six months following licensing of a drug. The new guidelines will not be retrospective, but will be valid for appraisals of treatments that are already under review by the agency.

Andrew Dillon, NICE chief executive, noted that agency officials are asking their advisors to give “greater weight” to life-extending drug treatments and stated that “the Institute is also conscious of its responsibility to support the development of novel treatments for smaller patient groups that provide innovative benefits over and above existing NHS care.”

Source: FirstWord

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DNA Repair Genes Previously Linked to Cancer Are Not Statistically Significant

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When the data from various studies associating DNA repair genes with cancer risk was combined, few of these variants were truly associated with increased cancer risk, according to a team of investigators from the University of Ioannina School of Medicine in Greece. Of the 241 variants studied, they found two that were statistically significant: XRCC1 allele (-77 T>C) and an allele of ERCC2 (codon 751) associated with lung cancer risk.

“The lack of many signals with strong credibility that emerged from our analysis, despite an enormous amount of work in this area over the years, needs careful consideration,” the authors write in a synopsis published online December 30 in the Journal of the National Cancer Institute. “The ability of the candidate gene approach to identify genetic risk factors may have been overestimated.

“Alternatively, the importance of the DNA repair pathway may have been exaggerated. However, there is increasing recognition that genetic risks of cancer conferred by single variants are almost always very modest. This means that even if the DNA repair pathway is essential for carcinogenesis, extremely large-scale evidence would be necessary to establish with high confidence the presence of specific associations.”

The scientists identified 241 previously reported associations between gene variants and the risk of cancer and reexamined these associations from 1,087 data sets. Initially 31 of the 241 associations appeared to be statistically significantly associated with cancer risk in the meta-analysis. Only XRCC1 allele (-77 T>C) and an allele of ERCC2 (codon 751), however, remained statistically significant after the researchers adjusted for multiple comparisons.

Thirtyone nominally statistically significant (i.e., P < .05 without adjustment for multiple comparisons) associations were recorded for 16 genes in dominant and/or recessive model analyses (BRCA2, CCND1, ERCC1, ERCC2, ERCC4, ERCC5, MGMT, NBN, PARP1, POLI, TP53, XPA, XRCC1, XRCC2, XRCC3, and XRCC4). XRCC1, XRCC2, TP53, and ERCC2 variants were each nominally associated with several types of cancer.

Three associations were graded as having strong credibility, another four had modest credibility, and 24 had weak credibility based on Venice criteria.

Requiring more stringent P values to account for multiplicity of comparisons, only the associations of ERCC2 codon 751 (recessive model) and of XRCC1 –77 T>C (dominant model) with lung cancer had P less than or equal to 0.0001 and retained P   less than or equal to 0.001 even when the first published studies on the respective associations were excluded.

Source: GEN News

Popularity: 7% [?]

Grape extract kills cancer cells

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An extract from grape seeds can destroy cancer cells, US research suggests.

In lab experiments, scientists found that the extract stimulated leukaemia cells to commit suicide.

Within 24 hours, 76% of leukaemia cells exposed to the extract were killed off, while healthy cells were unharmed, Clinical Cancer Research reports.

The study raises the possibility of new cancer treatments, but scientists said it was too early to recommend that people eat grapes to ward off cancer.

Grape seeds contain a number of antioxidants, including resveratrol, which is known to have anti-cancer properties, as well as positive effect on the heart.

Previous research has shown grapeseed extract has an effect on skin, breast, bowel, lung, stomach and prostate cancer cells in the laboratory.

It can also reduce the size of breast tumours in rats and skin tumours in mice.

However, the University of Kentucky study is the first to test its impact on a blood cancer.

Lead researcher Professor Xianglin Shi said: “These results could have implications for the incorporation of agents such as grapeseed extract into prevention or treatment of haematological (blood) malignancies and possibly other cancers.

“What everyone seeks is an agent that has an effect on cancer cells but leaves normal cells alone, and this shows that grapeseed extract fits into this category.”

The researchers exposed leukaemia cells to grape extract in a range of different doses.

Apoptosis

One of the higher doses produced a marked effect, causing large numbers of the cells to commit suicide in a process known as apoptosis.

This is a natural method of getting rid of damaged and potentially dangerous cells.

When the mechanism behind apoptosis breaks down, cancerous cells can survive and multiply.

The researchers found grapeseed extract activates a protein called JNK which helps to regulate apoptosis.

When they exposed the leukaemia cells to an agent that inhibits JNK, the grapeseed extract effect was cancelled out.

Silencing the gene that makes JNK also blocked the extract’s ability to kill cancer cells.

Kat Arney, Cancer Research UK’s senior cancer information officer, warned against jumping to firm conclusions.

She said: “This is yet another story highlighting the potential cancer-fighting properties of naturally-occurring chemicals.

“Although interesting, it’s still a long way from being a treatment that we can give to patients.”

Source: BBC NEWS

Popularity: 10% [?]

This Year’s Life Science Discoveries

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As we begin to contemplate what next year has to offer, it is useful to consider some key events of this year. Singling out one life science discovery as the breakthrough of the year is an impossible task. Here, we look at a few research segments —stem cells, genetic testing, HIV, cancer, and Alzheimer’s—and some interesting stories GEN covered.

Stem Cells: Scientists have not let the controversies surrounding embryonic stem cells (ESCs) dampen their resolve to realize the potential of this technology and stem cells in general. They found alternatives to using embryos, such as menstrual blood stromal cells. Researchers successfully reprogrammed adult stem cells into their embryonic-like state, revealed details about transcription factors used to do so, and found a way to identify pluripotent stem cells. Not to be stopped, scientists also delved into understanding embryonic stem cells as well as methods to derive and grow ESCs.

Genetic Testing: A key technique has been developed that if validated could mean a safer option to amniocentesis for detecting Down syndrome. The researchers leveraged shotgun sequencing on cell-free DNA from plasma from pregnant women.

Alzheimer’s: This disease continues to mystifies scientists, with the jury still out on what the root cause is. Industry and academia continue to cut away at the basics behind Alzheimer’s. Among this year’s findings is an imaging agent for earlier amyloid plaque detection, a method to carry treatments across the blood-brain barrier, and an invalidated mouse model.

Cancer: The news abounded with stories about genes and proteins associated with cancer, be it as a trigger to disease onset, a risk biomarker, or a prognostic indicator. These are undoubtedly important milestones in uncovering the biological network that this disease affects. Here we take a look at what we learned about cancer itself through revelations in cancer stem cell research, the process of tumorigenesis, and a couple of cancer genome analyses.

HIV: With as yet no cure for HIV and only a cocktail of drugs to keep symptoms at bay, scientists are plowing away. Papers this year further elucidated the structure of the virus and its mechanisms of actions. Researchers found clues to HIV resistance and made new discoveries to advance vaccines and therapeutics.

Below are some of this year’s highlights:

The Human Immunodeficiency Virus
Scientists Find Cellular Receptor for HIV
Scientist Reveals How HIV Protein Helps the Virus Evade the Immune System
HIV Overpowers Immune System Quicker than Previously Thought
Scientists Pinpoint Trio of Factors that Allow HIV to Cross the Blood-Brain Barrier
Investigators Reveal How HIV Infects CD4 T Cells
Researchers Reveal How HIV Protein Thwarts Immune System

HIV Resistance
Researchers Discover Gene Fusion Linked to HIV Resistance in Monkeys

Vaccines and Therapeutics
Researchers Identify Mechanism for Vaccines to Target HIV Protein
Scientists Identify Protein that Blocks HIV’s Entrance into T Cells
Identification of Host Cell Factors Could Lead to New Class of HIV Therapies
Investigators Engineer Immune Cells to See Past HIV-1’s Disguises

Source: GEN News Highlights

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Prescribing oncology drugs based on genetic profile may require more analyses, larger trials: FDA panel

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An FDA advisory panel stated Tuesday that drugmakers seeking to tailor the use of cancer drugs to patients with specific genetic profiles may be required to conduct larger clinical studies to obtain sufficient data. The panellists specifically discussed the K-ras gene mutation, which causes Eli Lilly’s and Bristol-Myers Squibb’s Erbitux and Amgen’s Vectibix to be ineffective in certain patients with colon cancer.

The panel members commented that additional analyses may be required to better screen individuals for gene mutations, and suggested that larger clinical studies could be needed to determine other biochemical factors that may affect drug efficacy. Committee chairperson Janice Dutcher indicated that more tissue samples from patients with cancer will also help regulators and physicians in determining which genes may affect treatment.

Eli Lilly and Amgen said that the companies have sufficient data to show that their drugs are most effective in patients with a normal K-ras gene and that they support label modifications to their products to include this information. Panel member Derek Raghavan noted: “Two companies have come to us to try to create a situation where they sell [fewer] products. This is the first time I’ve seen this at the FDA.”

Commenting on the news, Miller Tabak’s Les Funtleyder stated that “as technology gets better, drugs will be paired with a genetic test,” adding that “it’s unclear how this will play out economically.”.

Source: FirstWord

Popularity: 13% [?]

AstraZeneca Returns Worldwide Rights

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AstraZeneca today announced that it has returned worldwide rights to Infinity Pharmaceuticals for the development and commercialisation of Infinity’s heat shock protein 90 (Hsp90) drug candidates IPI-504 (MEDI-561) and IPI-493, in development for the treatment of cancer and related conditions.

The collaboration, initiated in August 2006 between MedImmune and Infinity, was transferred to AstraZeneca following its acquisition of MedImmune in June 2007.

After reviewing the potential opportunity for these projects within its portfolio and considering competing R&D investment priorities, AstraZeneca has decided to return the responsibility for development and commercialisation of this program to Infinity.

Infinity is fully committed to targeting Hsp90 as a potential new treatment approach to cancer, and to developing both IPI-504 and IPI-493. In particular, Infinity initiated a late stage trial of IPI-504 in patients with refractory gastrointestinal stromal tumors (GIST), a rare tumor of the gastrointestinal tract. IPI-504 and IPI-493 are in additional late- and early-stage ongoing clinical trials.

Source: AstraZeneca, Inc.

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Anavex presents potent neuroprotective effects of Anavex 1-41 at Neuroscience 2008

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Anavex Life Sciences Corp. (”ANAVEX”) (OTCBB), a biopharmaceutical company engaged in the discovery and development of novel therapeutics to treat Central Nervous System (CNS) diseases and cancer, was selected to present its latest results with ANAVEX 1-41 at Neuroscience 2008, the 38th annual meeting of the Society for Neuroscience, which took place November 15-19, 2008 in Washington, DC.

In a scientific poster abstract, ANAVEX detailed the outstanding neuroprotective potential of ANAVEX 1-41, evidenced by its ability to block the manifestation of the earliest toxic effects in a validated mouse model of Alzheimer’s disease. Currently in the late pre-clinical stage, ANAVEX 1-41 has shown synergistic potential for anti-amnesic and neuroprotective efficacy at extremely low doses. This is the first time these results have been attained by any pharmacological agent in an Alzheimer’s mouse model involving the injection of the amyloid-beta (25-35) peptide.

“We are excited by our ongoing progress in the development of ANAVEX 1-41 as it continues to demonstrate powerful neuroprotective action at extremely low doses with no toxicity,” said Dr. Vamvakides, Chief Scientific Officer of ANAVEX. “In addition, we believe that our latest findings have relevance for ANAVEX 2-73, another lead Alzheimer’s compound, as 1-41 and 2-73 have a common origin and similarities in mechanism of action.”

The earliest toxic effects of Alzheimer’s disease mouse models were measured by the expression of the caspase-12 marker. Caspase 12 is a recently discovered enzyme that indicates these early toxic effects. Non-transgenic Alzheimer’s mouse models are created by injecting amyloid-beta peptide (amyloid-beta 25-35) into mouse brains to bring on histological and biochemical changes, oxidative stress and learning deficits.

The neuroprotective potential of ANAVEX 1-41 is hypothesized to act by the compound’s ability to modulate sigma receptors which regulate calcium mobilization in neuronal cells. Calcium is regulated through the Inositol Triphosphate receptors “IP3R” and the sarcoendoplasmic reticulum “Ca2+/ATPase” pump.

The major effect of ANAVEX 1-41 occurs at the membrane of neuronal cells, in the endoplasmic reticulum (ER). The novel profile of ANAVEX 1-41, which is a mixed sigma-1, muscarinic and sodium-channel candidate drug, accounts for its ability to fight ER stress and thereby prevent apoptosis of the neuronal cells. This neuronal apoptosis is the prominent pathophysiological effect of brain degeneration in Alzheimer’s disease.

The neuroprotective effects of ANAVEX 1-41 were assessed in the hippocampus, the area of the brain that regulates learning, emotion and memory and which is highly implicated in Alzheimer’s disease. As recently discovered in pre-clinical testing, through its sigma-1 activity, ANAVEX 1-41 targets neuron structures (ER, mitochondria), as well as disturbed biochemical pathways and channels (UPR,IP3R,Bcl-2,apoptosis). Organizations involved in sigma receptor research, including ANAVEX, have determined that these are crucial factors in Alzheimer’s disease and in many other neurodegenerative diseases.

The company expects to complete pre-clinical trials on ANAVEX 1-41 in early 2009.

ANAVEX 1-41 and ANAVEX 2-73 share a common origin and related profile (congeners). ANAVEX is currently planning to prepare the Investigational New Drug (IND) (or IMPD) file to advance 2-73 to Phase 1 human clinical trials, which are expected to begin in 2009.

A copy of the poster abstract, titled “The neuroprotective action of ligands acting at the sigma-1 chaperone protein involves regulation of the expression of IP3 receptor subtypes and SerCa pumps,” can be viewed on the company’s web site at http://www.anavex.com/sfn08.html. The authors are Vanessa Villard, Fanny Malhaire-Ferreux, Francois Monnet, Alexandre Vamvakides and Tangui Maurice.

About Anavex Life Sciences Corp.

Anavex Life Sciences Corp. (www.anavex.com) is an emerging biopharmaceutical company engaged in the discovery and development of novel drug targets for the treatment of cancer and neurological diseases such as Alzheimer’s, epilepsy and depression. The company’s proprietary SIGMACEPTOR(TM) Discovery Platform involves the rational design of drug compounds that fulfill specific criteria based on unmet market needs and new scientific advances. Selected drug candidates demonstrate high, non-exclusive affinity for sigma receptors, which are involved in the modulation of multiple cellular biochemical signaling pathways.

ANAVEX’s SIGMACEPTOR(TM)-N program involves the development of novel and original drug candidates that target neurological and neurodegenerative diseases (Alzheimer’s disease, epilepsy, depression, pain). The company’s lead drug candidates exhibit high, non-exclusive affinity for sigma receptors with strong evidence for anti-amnesic, neuroprotective, anti-apoptotic, anti-oxidative, anti-inflammatory, anti-convulsive, anti-depressant and anxiolytic properties. The company believes that oxidative stress, not amyloid-beta, is the cause of Alzheimer’s. ANAVEX 1-41 and ANAVEX 2-73 modulate sigma receptors, a unique class of receptor molecules, to guard against oxidative stress and repair cells compromised by its effects. So far, through the advanced pre-clinical phase of development, the compounds have performed extremely well in well-recognized animal models of Alzheimer’s disease, underscoring the promise of the company’s new alternative approach to the disease.

ANAVEX SIGMACEPTOR(TM)-C program involves the development of novel and original drug candidates targeting cancer. The company’s lead drug candidates exhibit high, non-exclusive affinity for sigma receptors with strong evidence for selective pro-apoptotic, anti-metastatic and low toxicity properties in various types of solid cancers such as colon, prostate, breast and lung. ANAVEX 7-1037 has already demonstrated its ability to significantly delay the growth of cancerous tumors in patient-derived xenografts during advanced pre-clinical studies.

Forward-Looking Statements

Statements in this press release that are not strictly historical in nature are forward-looking statements. These statements are only predictions based on current information and expectations and involve a number of risks and uncertainties. Actual events or results may differ materially from those projected in any of such statements due to various factors, including the risks and uncertainties inherent in drug discovery and development, which include, without limitation, the potential failure of development candidates to advance through preclinical studies or demonstrate safety and efficacy in clinical testing and the ability to file an IND or commence clinical studies. You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date hereof. This caution is made under the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. All forward-looking statements are qualified in their entirety by this cautionary statement and Anavex Life Sciences Corp. undertakes no obligation to revise or update this press release to reflect events or circumstances after the date hereof.

Source: Anavex Life Sciences Corp.

Popularity: 21% [?]

Pharmaceutical companies abandon some work in general health to chase profits in cancer and Alzheimer’s

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Powerhouses of the pharmaceutical industry are abandoning research and development in areas that have brought them blockbuster profits over the past decade to tackle more lucrative diseases and avoid regulators who, the companies say, have become averse to risk.

Eli Lilly and Co., Abbott Laboratories, Wyeth Pharmaceuticals Inc. and Pfizer Inc. all have recently announced cuts in “primary care drugs” – drugs that treat ailments ranging from coughs and colds to heart disease and high cholesterol – in favor of drugs that treat more deadly diseases, are more likely to be approved, and require specialized care.

The companies are hoping to tap markets – notably cancer and Alzheimer’s— that are relatively free of competition, compared to say, cholesterol, said Damien Conover, a senior analyst at Morningstar Inc. Previously, drugs to treat cancer and Alzheimer’s had been considered too costly to develop due to a relatively small patient population, Conover said. But an aging population will likely increase the number of patients afflicted with the diseases.

Another factor in the shift to new areas is that drugs in formerly lucrative areas such as heart disease are becoming much more difficult to get approved because the Food and Drug Administration has become much more conscious of possible drug risks, Conover said.

The FDA became wary of approving new drugs after a few recent drug debacles in which the side effects of drugs far outweighed their benefits, Conover said. The arthritis pain reliever Vioxx, for example, was recalled by Merck after studies showed it caused heart attacks. Similarly, GlaxoSmithKline attached a warning to Avandia, a diabetes drug, after studies showed an increase in the incidence of heart attack.

“The FDA is starting to be a little more cautious,” Conover said. There’s little need to approve yet another cholesterol drug when Lippitor, for example, already treats high cholesterol and is relatively safe, he said.

The FDA has become so cautious, in fact, that the division responsible for reviewing new heart medicines didn’t approve a new heart drug for over four years on its “first pass through the agency,” according to a report by Scott Gottlieb, a scholar and fellow at the American Enterprise Institute for Public Policy Research. The heart medicine division has the toughest record of the FDA’s drug review groups, Gottlieb said.

But the FDA seems willing to make more tradeoffs in cancer and Alzheimer’s treatments because fewer drugs exist to treat the diseases, and the diseases are much more deadly.

“It is one thing when a cancer drug causes some uncommon but devastating side effect,” Gottlieb said, “quite another when a common cold pill is at question, or a routine pain medicine like Merck’s Vioxx.”

Another advantage for drug makers: the deadly nature of cancer and Alzheimer’s allows companies to charge much more.

“You can still get a blockbuster drug with a smaller patient population,” said Conover.

The drugs for Alzheimer’s and cancer also tend to be drugs that patients will have “to take every day for the rest of their life,” which makes them all the more profitable, said John Flavin, director and president of Advanced Life Sciences Inc., a small biotechnology company in Illinois.

Large drug makers will also benefit by switching to specialized drugs because it costs less to market a drug to the relatively small number of oncologists and Alzheimer’s specialists compared to the much greater number of primary care physicians that must be reached to market primary care drugs, said Linda Bannister, an analyst at Edward Jones & Co.

The companies are all but sure to reap profits from the strategy, according to IMS Health Inc., a pharmaceutical market research firm. Global sales of cancer drugs will grow at a compounded annual rate of 12 to 15 percent through 2012 – nearly double the forecasted growth rate of the pharmaceutical market at large, according to IMS Health.  The cancer market is expected to exceed $48 billion this year, so the projection indicates a leap to $75 billion to $80 billion by 2012.

But there is a societal danger in the switch toward developing medicines for deadly but exotic diseases: while the small number of people afflicted by deadly diseases will be helped, the health of the general population might suffer as research into primary care drugs is abandoned, according to Gottlieb.

“Even small improvements offered by slightly better medicines like new generations of drugs for pain or blood pressure can yield big benefits when aggregated over large populations,” Gottlieb said. If big pharmaceuticals abandon research in to these drugs, “patients will lose the chance to gain relief from more of life’s daily medical problems.”

But drug companies offer another possibility. They say that while big pharmaceutical companies may shift focus from primary care drugs to specialty drugs, the slack in primary care research will be taken up by smaller biotechnology companies.

That’s just what happened with Abbott Laboratories and Advanced Life Sciences Inc. Abbott sold the rights to a promising new antibiotic, cethromycin, to Advanced Life Sciences to pursue drugs in new areas. After years of development, Advanced Life Sciences has submitted a new drug approval request to the FDA and hopes to start marketing cethromycin for the treatment of pneumonia in late 2009.

In the end, both patients and shareholders are likely to benefit as the big companies give up research and development in certain areas, even potentially deadly ones like heart disease, Bannister contends.

Drug makers have “made so much progress in the cardiovascular arena already,” she said. Relatively few drugs exist, however, for the treatment of cancer.

“It’s better for patients, it’s better for pharmaceuticals because they get a better return on investment,” she said. “It’s a win-win.”

But Gottlieb has a different take: “The days of expensive research into ordinary problems is ending, and with it the population-wide public health gains that we may have taken for granted.”

Source: Medill Reports - Chicago

Popularity: 23% [?]

Scientists track genetic changes in leukemia

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WASHINGTON - Distinctive genetic changes occur in the cancer cells that trigger relapse in patients with the most common type of childhood cancer, according to a study that may offer new hope for beating the disease.

Writing in the journal Science on Thursday, the scientists described key genetic differences in cancer cells of children with acute lymphoblastic leukemia, or ALL, when they were first diagnosed compared to when they had a relapse.

ALL is a cancer of the blood and bone marrow. Most children with it can be cured, but among those who suffer a relapse only about 30 percent survive.

The genetic changes in the cancer cells in relapsed ALL patients often affected the biological machinery involving white blood cells called B cells as well as tumor suppression genes, the researchers said.

Rarely did the changes affect genes directly involved in regulating responsiveness to cancer drugs, they said.

“If we are to develop new selective and less toxic treatments for leukemia, we have to have a complete understanding of all of the different genetic changes that contribute to leukemia and contribute to this process of relapse,” said Dr. Charles Mullighan of St. Jude Children’s Research Hospital in Memphis, Tennessee, one of the researchers.

“We’ve pinned them down to certain cellular pathways that are important,” Mullighan said in a telephone interview.

The hope is that by unraveling the genetic factors that help determine whether a person suffers a relapse, scientists can create drugs that may disrupt the process.

“That’s our ultimate goal,” Mullighan said.

The researchers compared the genomes of cancer cells of 61 children with ALL when they were initially diagnosed and after they had relapsed.

“The key finding in our work is that in the majority of cases, relapse is arising from a cell already present at the time of diagnosis,” St. Jude’s Dr. James Downing, another of the researchers, said in a statement. “That cell is selected for during treatment and then subsequently emerges as basis for relapse.”

The researchers proposed that there is an ancestral leukemia cell that gives rise to the cell that causes the initial illness and to another cell that later may emerge as the deadlier relapse cell.

Mullighan said the cure rate for children with ALL exceeds 80 percent around the world. But perhaps 20 percent to 25 percent of children with ALL suffer a relapse.

Source: Reuters

Popularity: 13% [?]

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