Institute of Cancer Research

Cancer diversity ‘threatens drugs’

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A single tumour can be made up of many separate cancers needing different treatments, say researchers.

A team at the Institute of Cancer Research, London, have developed a new technique for measuring the diversity within a cancer.

Cancer cells

They showed “extraordinary” differences between cancerous cells and say new targeted drugs may fail as they may be unable to kill all the mutated tissue.

Experts said the findings would have “profound implications” for treatments.

A tumour starts as a single cell, which acquires mutations and eventually divides uncontrollably. But that is not the end of the process.

Cancerous cells continue to mutate and become more aggressive, move round the body and resist drugs.

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Every patient has a completely new tree and doesn’t have one cancer, they have multiple cancers”

Prof Mel Greaves Institute of Cancer Research

This process is chaotic and results in a “diverse” tumour containing cancerous cells that have mutated in different ways.

“This has huge implications for medicine,” researcher Prof Mel Greaves told the BBC.

His team at the Institute of Cancer Research investigated cancer diversity in five children with leukaemia. They compared mutations in individual cancerous cells with a known database of mutations.

Their results, published in the journal Genome Research, showed patients had between two and 10 genetically distinct leukaemias.

Prof Greaves said: “Every patient has a completely new tree and doesn’t have one cancer, they have multiple cancers.

“This is really a technical advance to get at this extraordinary complex diversity, it helps explain why we have such difficulty with advanced diseases.”

Tree of cancer

Scientists compare cancer diversity to a tree. The initial mutations – the trunk – will be common to all cancer cells. But then the tumour branches out.

Tree
Drugs need to target the trunk of a tumour say researchers

It means a treatment that targets one “branch” or sub-clone of the cancer might slow the disease, but they will never stop it.

Prof Charles Swanton, who researches diversity at the University College London Cancer Institute, told the BBC: “We call it pruning the branches not cutting down the tree, targeted therapies will remove some of the sub-clones, but chopping down the tree is hard to do.”

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The bottom line is we need to understand cancer diversity to limit further adaptations, reduce the pace of evolution and prolong the activity of drugs”

Prof Charles Swanton UCL

The study investigated leukaemia as it is less diverse than other types of cancer. Other tumours such as melanoma could feasibly be made of hundreds of branches.

Prof Greaves says one implication of the research is that therapies need to be developed which target the trunk of the tumour and that current targeted therapies being researched may not tackle advanced cancers.

Another idea he suggests is focusing on the cancer’s surroundings as well.

“If it is diversifying like species in a habitat, why not target the habitat – the blood vessels supplying oxygen or inflammation. There’s a lot of interest in that,” he said.

The research also emphasises the importance of catching cancers early before they have become too diverse to treat.

Prof Charles Swanton argues: “The bottom line is we need to understand cancer diversity to limit further adaptations, reduce the pace of evolution and prolong the activity of drugs.”

Prof Chris Bunce, the research director at Leukaemia and Lymphoma Research, commented: “We are beginning to understand how unique and complex each patient’s cancer is and the profound implications that this can have on the success of treatment.

“This study significantly advances our understanding of how cancers start and evolve.”

New cancer drugs now being allowed to skip clinical trials.

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The regulatory framework that guides the approval process for new pharmaceutical drugs is becoming increasingly compromised, as drug companies continue to chip away at its core functions. And according to a new report by Reuters, new cancer drugs are among the worst regulatory offenders these days, with many of them now completely bypassing the normal clinical trial process, as they are rushed to market as quickly as possible.

Framed as a positive development for the thousands of people suffering from cancers that do not respond to traditional chemotherapy and radiation, the U.S. Food and Drug Administration‘s (FDA) relatively recent expedited review process for immunotherapy cancer drugs is making experimental medications more widely available to desperate patients. But is Big Pharma taking advantage of this desperation by using it as an opportunity to skip the clinical trial process?

Since the typical approval process for new drugs is both lengthy and costly, sometimes lasting a decade or more and costing upwards of $1 billion per drug, according to some reports, drug companies have long sought shortcuts that might help bypass this laborious process. And now they have finally found a way, convincing higher-ups at the FDA to shorten the approval process and get new drugs to market more quickly.

Back in August, we reported that the FDA passed a new “Safety and Innovation Act” back in 2012 that allows untested, but allegedly promising, drugs to be rushed to market under the designation of “breakthrough therapy.” Such therapies do not have to undergo full-scale clinical trials and can simply be approved based on preliminary clinical evidence that points to “substantial improvements” over existing drugs.

But the process is largely arbitrary and serves to benefit the drug industry far more than suffering patients. According to Dr. Alexander Eggermont, chief executive of the Institut Gustave-Roussy, France’s largest cancer center, the immunotherapy class of drugs has the potential to become a $35 billion a year market, which means rapid approvals will translate into big bucks for Big Pharma.

“We won’t have to do those dinosaur trials,” Dr. Eggermont is quoted as saying by Reuters, noting that immunotherapy drugs are the “biggest game changer” the industry has ever seen. “It will change the whole attitude in drug development.”

Big Pharma sidestepping regulatory approval process with bogus claims of drug price decreases

In a further attempt to legitimize this obvious sidestepping of regulatory standards, the drug industry has also posed the idea that its drugs may become less expensive as a result of having to wade through fewer regulatory hurdles. As anyone with a family member who has gone through the traditional cancer treatment process can attest, the costs of chemotherapy drugs and radiation can top hundreds of thousands of dollars annually, which makes lower costs enticing.

But many experts are already saying that this is not actually the case, and that drug prices have yet to drop in any substantial way. Even though the typical clinical trial process for drug approvals is estimated to represent more than one-third of the overall research and development (R&D) costs for drug companies, the adoption of an expedited process for some drugs has not led to any significant changes.

“The costs should be coming down tremendously,” says Paul Workman, head of drug discovery at the UK’s Institute of Cancer Research, as quoted by Reuters. “What’s disappointing is that we haven’t seen it happen yet.”

Source: NaturalNews.com