Tag: DNA

Genetically engineered virus kills cancer

by The Age of Blasphemy, posted in Genetically engineered virus kills cancer, JX-594, Pexa-Vec

Genetically engineered virus kills cancer

Sixteen patients given a high dose of the therapy survived for 14.1 months on average, compared to 6.7 months for the 14 who got the low dose.

“For the first time in medical history we have shown that a genetically engineered virus can improve survival of cancer patients,” study co-author David Kirn told AFP.

The four-week trial with the vaccine Pexa-Vec or JX-594, reported in the journal Nature Medicine, may hold promise for the treatment of advanced solid tumours.

“Despite advances in cancer treatment over the past 30 years with chemotherapy and biologics, the majority of solid tumours remain incurable once they are metastatic (have spread to other organs),” the authors wrote.

There was a need for the development of “more potent active immunotherapies”, they noted.

Pexa-Vec “is designed to multiply in and subsequently destroy cancer cells, while at the same time making the patients’ own immune defence system attack cancer cells also”, said Kirn from California-based biotherapy company Jennerex.

“The results demonstrated that Pexa-Vec treatment at both doses resulted in a reduction of tumour size and decreased blood flow to tumours,” said a Jennerex statement.

“The data further demonstrates that Pexa-Vec treatment induced an immune response against the tumour.”

Pexa-Vec has been engineered from the vaccinia virus, which has been used as a vaccine for decades, including in the eradication of smallpox.

The trial showed Pexa-Vec to be well tolerated both at high and low doses, with flu-like symptoms lasting a day or two in all patients and severe nausea and vomiting in one.

The authors said a larger trial has to confirm the results. A follow-up phase with about 120 patients is already under way.

Pexa-Vec is also being tested in other types of cancer tumours.

A patient undergoes a scanner as radiology technicians look at the exam on a screen, on February 6, 2013, at a medical unit specialised in cancer treatment in France. A genetically-engineered virus tested in 30 terminally-ill liver cancer patients significantly prolonged their lives, killing tumours and inhibiting the growth of new ones, scientists reported on Sunday.

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Antioxidants May Actually Be Causing Cancer

by The Age of Blasphemy, posted in Antioxidants, Cancer

James Watson Says Antioxidants May Actually Be Causing Cancer
Annalee Newitz

James Watson Says Antioxidants May Actually Be Causing Cancer

Celebrated geneticist James Watson, one of several researchers who won the Nobel Prize for discovering the structure of DNA, has just published what can only be called a cancer manifesto in Open Biology. It’s full of fairly harsh criticisms for current cancer researchers, but also suggests several ways forward in the “war on cancer.” Among other claims, Watson asserts that antioxidants like vitamin C — often recommended as cancer-prevention supplements — could be causing some forms of cancer. He also has harsh words for personalized medicine, and the laziness of cancer researchers.

Watson, now in his 80s, has spent a great deal of his life raising money to fund cancer research at Cold Spring Harbor Laboratory, where he’s served as director since the late 1960s. Clearly anticipating his own mortality, he mourns the lack of good leadership in cancer research:

That we now have no General of influence, much less power, say an Eisenhower or even better a Patton, leading our country’s War on Cancer says everything. Needed soon is a leader that has our cancer drug development world working every day and all through the night.

He suggests that the problem is researchers are slacking, only putting in “never frantic, largely five-day working week[s].”

He goes on to say that the current craze for “personalized medicine” that will treat cancer is just not going to work. But the main problem comes from government money being misspent:

The now much-touted genome-based personal cancer therapies may turn out to be much less important tools for future medicine than the newspapers of today lead us to hope. Sending more government cancer monies towards innovative, anti-metastatic drug development to appropriate high-quality academic institutions would better use National Cancer Institute’s (NCI) monies than the large sums spent now testing drugs for which we have little hope of true breakthroughs. The biggest obstacle today to moving forward effectively towards a true war against cancer may, in fact, come from the inherently conservative nature of today’s cancer research establishments.

He goes on to say that conventional thinking about cancer is all wrong. Antioxidants may be undermining cancer therapies and even causing cancer:

In light of the recent data strongly hinting that much of late-stage cancer’s untreatability may arise from its possession of too many antioxidants, the time has come to seriously ask whether antioxidant use much more likely causes than prevents cancer.

All in all, the by now vast number of nutritional intervention trials using the antioxidants β-carotene, vitamin A, vitamin C, vitamin E and selenium have shown no obvious effectiveness in preventing gastrointestinal cancer nor in lengthening mortality. In fact, they seem to slightly shorten the lives of those who take them. Future data may, in fact, show that antioxidant use, particularly that of vitamin E, leads to a small number of cancers that would not have come into existence but for antioxidant supplementation. Blueberries best be eaten because they taste good, not because their consumption will lead to less cancer.

It is thought that antioxidants can prevent damage to DNA from oxygen radicals. But, argues Watson, we want oxygen radicals in cancer cells because this can cause the cells to die. Taking antioxidants might be preventing cancer drugs from destroying cancer cells. Instead, he recommends patients combine anti-antioxidants with cancer drugs.

Watson also recommends an area of research, into a class of proteins called RNAi, which can be used to shut down the activity of genes. He claims that we need less than a billion dollars to win the war on cancer if we focus on RNAi research:

The total sum of money required for RNAi methodologies to reveal the remaining major molecular targets for future anti-cancer drug development need not be more than 500–1000 million dollars. Unfortunately, the NCI now is unlikely to take on still one more big science project when it is so hard-pressed to fund currently funded cancer programmes … Further financial backing, allowing many more cancer-focused academic institutions to also go big using RNAi-based target discovery as well as to let them go on to the early stages of subsequent drug discovery, is not beyond the might of the world’s major government research funding bodies nor that of our world’s many, many super billionaires. The main factor holding us back from overcoming most of metastatic cancer over the next decade may soon no longer be lack of knowledge but our world’s increasing failure to intelligently direct its ‘monetary might’ towards more human-society-benefiting directions.

Watson also wants researchers to focus on a protein called Myc, which is believed to regulate the activity of 15% of our genes. Its activity is also linked to many kinds of cancer. Using RNAi methods, it’s possible we could figure out a way to control Myc, and thus shut down pathways to cancer.

Further Reading:

Watson’s manifesto, “Oxidants, antioxidants, and the current incurability of metastatic cancers,” in Open Biology

Reuters’ Sharon Begley has a good report on what other cancer researchers think about Watson’s comments.

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SCIENCE HAS SURPASSED SCRIPTURE | Sam Harris

by The Age of Blasphemy, posted in Bible, Sam Harris, SCIENCE HAS SURPASSED SCRIPTURE, Scripture

SCIENCE HAS SURPASSED SCRIPTURE

Science has surpassed scripture - science, scripture, quotes, sam harris, the bible, koran,

 I mean just think of how good a book would be if it were authored by an omniscient deity. I mean, there is not a single line in the bible or the koran that could not have been authored by a first century person. There is not one reference to anything – there are pages and pages about how to sacrifice animals, and keep slaves, and who to kill and why. There’s nothing about electricity, there’s nothing about DNA, there’s nothing about infectious disease, the principles of infectious disease. There’s nothing particularly useful, and there’s a lot of iron age barbarism in there, and superstition. This is not a candidate book.
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DNA Discovery May Boost Stem Cell Safety

by The Age of Blasphemy, posted in Science News

DNA discovery may boost stem cell safety

Monday, 28 November 2011 Sarah Kellett ABC

Petri dishes

Stem cells need to be grown in the best possible way to stop gene mutations(Source: iStockphoto)

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Regenerative medicine A region of DNA that can boost the growth of stem cells has been found in the largest ever study of human embryonic stem cells.

The discovery could lead to safer cell therapies, says  study co-author Dr Andrew Laslett from CSIRO Materials Science and Engineering.

The research by the International Stem Cell Initiative involved 38 laboratories across the globe studying 125 ethnically diverse cell lines in parallel experiments.

Study findings, reported in today’s issue of Nature Biotechnology , uncover changes that arise from how cells are grown.

Embryonic stem cells are powerful for their ability to become any other cell in the body.

Stem cell therapy, which is entering early-stage human trials, turns stem cells into other cell types, like healthy nerve cells, to treat spinal cord injury, blindness and other ailments.

The cells need to be grown in nutritious culture to produce enough cells for therapy. Many stem cells die when they are first moved to a new culture, leading to natural selection and adaptation.

Cells with a growth advantage expand faster and dominate. However, this can come at the price of genetic mutation, so growing fast is not always desirable.

“It’s the small fraction of cells that become abnormal that can be dangerous in a clinical situation,” says Laslett. “If they find growth situations that suit them, they could grow into cancers.”

One in five cell-lines mutated a particular region of chromosome 20. Gaining extra copies of the region seemed to give them a growth advantage.

From the three genes in the region, it’s likely the advantage is from BCL2L1. It’s known to stop controlled cell death, or apoptosis. The same mutation is also found in some cancer cells.

By targeting this region of chromosome 20, Laslett says we can “develop better tests to tell more quickly if the cells are going bad in culture.”

Scientists could use these tests to improve current techniques used to grow stem cells.

“Embryonic stem cells walk a tightrope with maintaining their normal genetic nature,” he says. “We need to culture them in the best possible way so they keep those genes normal.”

International collaboration

Associate Professor Paul Thomas at the University of Adelaide, who was not involved in the study, says the research is impressive in its scale.

“This kind of paper wouldn’t be possible without international collaboration.”

“One of the interesting findings is that most of the embryonic stem cells are normal, even though they have been cultured for a long period. About two thirds were unchanged,” he says.

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