Breast cancer heterogeneity no barrier to predictive testing, study shows

5th IMPAKT Breast Cancer Conference

2013-05-02

(Press-News.org) Lugano-CH, Brussels-BE, 2 May 2013 -- Breast cancers contain many different cell types with different patterns of gene expression, but a new study provides reassurance that this variability should not be a barrier to using gene expression tests to help tailor cancer treatments to individual patients.

The findings were reported at the 5th IMPAKT Breast Cancer Conference in Brussels, Belgium. The IMPAKT meeting presents cutting edge, 'translational' breast cancer research that is beginning to have an impact for patients.

In recent years it has become clear that breast cancers contain a variety of different cell types. An important result of this heterogeneity is that different biopsy specimens from a single breast cancer tumour can exhibit significant variability in genes expression.

This is a major concern for doctors seeking to understand which patients are likely to benefit from drugs designed to be effective against tumour cells with particular genetic characteristics. A number of studies at this year's IMPAKT conference consider this issue.

In one study, Dr Michał Jarząb and colleagues from the Maria Skłodowska-Curie Memorial Cancer Center and Institute of Oncology, Poland took a total of 78 different biopsies from 26 individual tumours to assess the degree of genomic variation, and its impact on a set of 32 different prognostic and predictive multi-gene signatures.

"Some genomic tests have proven very useful in breast cancer, but in other important areas we have not achieved optimal results," Dr Jarząb explains. "One of these areas where we haven't done so well is in deciding whether a particular patient would benefit from certain type of chemotherapy or not, based on the material from pre-surgical needle biopsies. We hypothesized that some genomic tests may be prone to the heterogeneity of starting material and provide not reliable results."

The researchers performed gene expression profiling on their 78 samples using oligonucleotide microarrays. Overall, they found that the gene expression profiles of the cores were variable, and in at least 5 patients this heterogeneity was substantial.

However, when they analysed a number of multi-gene signatures selected from previous studies, this heterogeneity was considerably less significant.

The gene sets differed in their variance between biopsies, the authors found. The most pronounced heterogeneity was observed in immune response-related genes, while the least heterogeneous were the classifiers based on genes selected by advanced bioinformatical methods from both cell culture experiments and patient tissues.

"Overall, the heterogeneity among the potentially predictive genes was small enough and we conclude that this factor should not prohibit their effective use in clinical practice," Dr Jarząb says.

"Our study confirms that it is possible to address tumour heterogeneity when carrying out routine diagnostic procedures in patients. Our results may help to introduce the better tailoring of preoperative treatment."

Commenting on the results, Dr. Angelo Di Leo, Head of the Sandro Pitigliani Medical Oncology Unit and Chair of the Oncology Department at the Hospital of Prato, Istituto Toscano Tumori, Italy, said: "If other studies report similar results to this one, then it could become common practice to evaluate prognostic or predictive breast cancer markers from more than one primary tumour area."

"The study is innovative because it is one of the first to address the question of intratumour heterogeneity. It means that not all the cells from the same tumour have the same characteristics, and if we want to have a clear picture of the tumour biology we should not limit the evaluation of tumour markers to one area of the tumour itself," Dr. Di Leo said. ### END

ELSE PRESS RELEASES FROM THIS DATE:

Primate hibernation more common than previously thought

2013-05-02

DURHAM, N.C. -- Until recently, the only primate known to hibernate as a survival strategy was a creature called the western fat-tailed dwarf lemur, a tropical tree-dweller from the African island of Madagascar. But it turns out this hibernating lemur isn't alone. In a study appearing May 2 in the journal Scientific Reports, researchers report that two other little-known lemurs -- Crossley's dwarf lemur and Sibree's dwarf lemur -- burrow into the soft, spongy rainforest floor in the eastern part of Madagascar, curl up and spend the next three to seven months snoozing ...

Duke researchers identify gene mutations associated with nearsightedness

2013-05-02

DURHAM, N.C. -- People have long taken for granted that glasses and contact lenses improve vision for nearsightedness, but the genetic factors behind the common condition have remained blurry. Now researchers at Duke Medicine are closer to clearing this up. Mutations in a gene that helps regulate copper and oxygen levels in eye tissue are associated with a severe form of nearsightedness, according to a study published in the American Journal of Human Genetics on May 2, 2013. Nearsightedness – also known as myopia – is the most common human eye disease in the world. ...

New imaging technique to visualize bio-metals and molecules simultaneously

2013-05-02

Metal elements and molecules interact in the body but visualizing them together has always been a challenge. Researchers from the RIKEN Center for Life Science Technologies in Japan have developed a new molecular imaging technology that enables them to visualize bio-metals and bio-molecules simultaneously in a live mouse. This new technology will enable researchers to study the complex interactions between metal elements and molecules in living organisms. Metal elements such as zinc, iron and copper are present in trace amounts in the body and play an important role ...

Scientists revolutionize the creation of genetically altered mice to model human disease

2013-05-02

CAMBRIDGE, Mass. (May 2, 2013) – Whitehead Institute Founding Member Rudolf Jaenisch, who helped transform the study of genetics by creating the first transgenic mouse in 1974, is again revolutionizing how genetically altered animal models are created and perhaps even redefining what species may serve as models. "This new method is a game changer," says Jaenisch, who is also a professor of biology at MIT. "We can now make a mouse with five mutations in just three to four weeks, whereas the conventional way would take three to four years. And it's rather straightforward, ...

Bigger birth weight babies at greater risk of autism

2013-05-02

It is the first time that a clear link has been made between babies who grow to above average size at birth and risk of Autism Spectrum Disorder and follows from a study of more than 40,000 child health records in Sweden. The research, led by The University of Manchester, also confirms earlier research which reported that premature and poorly grown, low weight babies appear more susceptible to the condition. Autism affects how individuals interact with the world and with other people and there is no known cure. One child in 100 has the condition in the UK according ...

No greater death risk for children admitted to emergency out-of-hours intensive care

2013-05-02

Children admitted to UK intensive care units in out-of-hours emergencies are at no greater risk of dying than children arriving during normal working hours, according to new research. However, mortality rates are significantly higher in the winter, even after taking into account added health risks for children in the colder months. The study, published by researchers at the University of Leeds and the University of Leicester in the Journal of Pediatrics, is the first large-scale analysis of the influence of admission times on deaths in paediatric intensive care units. ...

Newly-discovered human fat cell opens up new opportunities for future treatment of obesity

2013-05-02

The body's brown fat cells play a key role in the development of obesity and diabetes. Researchers at Sahlgrenska Academy, University of Gothenburg, Sweden, have now discovered that we humans have two different kinds of brown fat cells and not one kind as previously thought. This discovery, now published in Nature Medicine, opens up new opportunities for future medicines that exploit the brown fat cells' ability to consume calories. Unlike white fat cells, which store the body's surplus energy in the form of fat, brown fat cells have the unique property of being able ...

Exercise proves to be ineffective against care home depression

2013-05-02

Researchers at the University of Warwick and Queen Mary, University of London have shown that exercise is not effective in reducing burden of depression among elderly care home residents. Exercise is a low risk intervention that can improve mental health but the findings of a National Institute for Health Research Health Technology Assessment Programme study, published in The Lancet, conclude that there is a requirement for alternative approaches to reduce the burden of depression in frail, very elderly, care home residents. The large randomised controlled trial sought ...

Stem cell discovery could aid research into new treatments

2013-05-02

Scientists have made a fundamental discovery about how the properties of embryonic stem cells are controlled. The study, which focuses on the process by which these cells renew and increase in number, could help research to find new treatments. Researchers have found that a protein, which switches on genes to allow embryonic stem cells to self-renew, works better when the natural occurring level of the protein is reduced. It was previously thought that once levels of this protein – called Oct 4 – were reduced the numbers of new stem cells being produced would also ...

More effective, cheaper concrete manufactured with ash from olive residue biomass

2013-05-02

University of Granada researchers have successfully manufactured self-compacting concrete using ash from the combustion of olive pruning residue pellets. Due to its plasticity and cohesion, this type of concrete needs no compaction when used in construction and has many advantages over conventional concrete, resulting in considerable savings of time and money. In an article published in "Construction and Building Materials", the researchers present preliminary results on the use of fly ash, produced in domestic boiler combustion of biomass olive residue pellets, as a ...

Breast cancer heterogeneity no barrier to predictive testing, study shows

ELSE PRESS RELEASES FROM THIS DATE:

LAST 30 PRESS RELEASES: