A cancer-treating technique being studied at the University of Pennsylvania has had dramatic results for some of the patients involved. Thanks to an experimental leukemia treatment the team first tried last year, 7-year-old Emma Whitehead is now in remission, the scientists have reported at a meeting of the American Society of Hematology this week. She is one of a dozen patients that have undergone the treatment; a third of those patients are now cancer-free.
What’s the News: After a bone marrow transplant cured a Berlin man of HIV in 2008, scientists have been working to see whether similar, though less drastic, measures could be a treatment for the disease. And judging from the results of a recent clinical trial that used gene therapy to accomplish the goal, there’s potential.
What’s the Context:
What’s the News: Medicine in the age of genes overflows with daring new techniques and treatments, from personalized chemotherapy to prenatal genetic testing, each heralded as a game-changer. But rarely do we get an assessment of a treatment’s long-term good, which is why recent papers following up on one of the most controversial genetic treatments, gene therapy, are making waves: though one patient developed leukemia from the treatment, 13 of 16 kids treated with gene therapy for a severe immune disorder at least 9 years ago have been cured, adding to the sense that the field is on its way to recovery from early setbacks.
Modified immune cells decimated chronic lymphocytic leukemia, scientists found.
What’s the News: Striking results in a very small study have got the web a-buzz about a new cancer treatment: With three leukemia patients at the ends of their ropes, scientists modified some of their immune cells with a gene that enabled them to hunt down cancer cells. Remarkably, the treatment wiped out more than two pounds of tumor tissue in each patient, and the three have now been in remission for a year.
But what weight does such a small study carry, what about the side effects, and what do these results mean for people with other cancers?
What’s the News: Scientists have identified three gene mutations that lead to acute myeloid leukemia, a cancer that afflicts white blood cells, which may lead to better cancer drugs in the future. As Wellcome Trust Sanger Institute hematologist George Vassiliou told the BBC, his team’s study “found critical steps that take place when the cancer develops. Identifying the biological steps … means we can look for new drugs to reverse the process.”
How the Heck:
What’s the Context:
Not So Fast: Researchers caution that it could take decades before new cancer-fighting drugs based on this study come on the market. This present study only used mice as subjects.
Reference: George S Vassiliou et al. “Mutant nucleophosmin and cooperating pathways drive leukemia initiation and progression in mice.” Nature Genetics. doi:10.1038/ng.796
Image: Wikimedia Commons / Bruce Wetzel
Perhaps you’ve seen the story of the 44-year-old American man reportedly “cured” of HIV in Germany–it’s been making the rounds over the past week. What’s actually happening here?
This is a story that dates back a few years; in fact, 80beats blogged about this case years ago when it first made the news. Back in 2007, the man—Timothy Ray Brown—was an HIV-positive patient suffering from acute myeloid leukemia. When standard chemotherapy couldn’t help him, his docs in Germany turned to a bone marrow transplant, with one twist.
Brown’s oncologist decided to look for a bone marrow donor who had a had a special genetic mutation that made the stem cells in it naturally resistant to HIV infection. His physician, Dr. Gero Huetter, was able to find this rare match and Brown got the bone marrow transplant. He needed a second stem cell transplant because the cancer came back. Today, he appears to be cancer free and doctors can’t find traces of the virus that causes AIDS either. [CNN]
Brown’s treatment made a splash in the news in 2008, when the doctors first reported on it. It has resurfaced this month because the researchers published a new study in the journal Blood updating his condition.
The researchers confirmed that Brown seems to have maintained his resistance to HIV for three years, confounding their expectation that he would become reinfected. They concluded that a “cure of HIV has been achieved in this patient.” [New Scientist]
The latest entry into the cellphones-radiation-health debate is a British study of thousands of children, which investigated whether the proximity of pregnant women to cellphone towers had any effect on whether their kids developed tumors or leukemia. The result: a big no.
Researchers from Imperial College London identified 1,397 children under five who were diagnosed with leukaemia or a tumour of the brain or central nervous system between 1999 and 2001. They compared each child with four children of the same gender who were born on the same day but had not developed cancer [The Guardian].
They then cross-compared all those children to how much radiation their mothers likely received during pregnancy, based on a survey of more than 80,000 cell towers and their radiation output. No matter how they ran the numbers, the team couldn’t find a significant effect.
For instance, the mothers whose children were diagnosed with cancer lived an average of 1,173 yards from a cellphone tower while they were pregnant — statistically indistinguishable from the 1,211 yards that separated the other pregnant women from their nearest cellphone towers. Tallying up the total power output of all cellphone towers within 766 yards of each pregnant woman’s home, they found that both groups had nearly the same exposure — 2.89 kilowatts for the mothers of cancer victims and 3.00 kilowatts for the other mothers [Los Angeles Times].
In very rare cases, the womb is a dangerous place for a developing fetus. Researchers have found that pregnant women can pass on cancer cells to their unborn babies, if those cancer cells carry a particular genetic mutation. The new study resolves a longstanding puzzle, because in theory any cancer cells that manage to cross the placenta into the baby’s bloodstream should be targeted for destruction by the child’s immune system. But there are records of 17 cases of a mother and baby appearing to share the same cancer – usually leukaemia or melanoma [BBC News].
In the study, which will be published in Proceedings of the National Academy of Sciences, researchers used a genetic “fingerprinting” technique to match the cancer cells found in a mother and baby. The case, involving a Japanese mother aged 28 and her daughter, revealed that both patients’ leukaemic cells carried the identical mutated cancer gene BCR-ABL1 even though the infant had not inherited this gene [The Times]. This meant that the child, who was diagnosed with cancer at the age of 11 months, could not have developed leukemia independently.
In a remarkable announcement, German researchers have declared that they “functionally cured” a patient of AIDS, eradicating all traces of the virus from his body. The feat was accomplished with a bone marrow transplant from a donor who had a genetic resistance to the virus, and researchers say that 20 months later they can find no trace of the virus in the patient’s blood, bone marrow, or organ tissue.
But the accomplishment shouldn’t be taken as a sign that a cure for the 33 million people living with AIDS is around the corner, researchers are hasty to add. Professor Rodolf Tauber from the [German] clinic said: “This is an interesting case for research. But to promise to millions of people infected with HIV that there is hope of a cure would not be right” [BBC News]. Reasons for this caution include the small number of potential donors with the HIV-resistant mutation, and the difficulty and expense of bone marrow transplants.
For the first time researchers have sequenced the complete genome of a cancer cell, and they say the process turned up eight previously unknown genetic mutations that played a role in the patient’s terminal leukemia. As it gets cheaper and easier to decode entire genomes, as opposed to just checking “usual suspect” stretches of DNA, doctors hope to decode the genomes of many different types of cancer. Eventually, researchers say cheap techniques may allow doctors to study the cancer genomes of individual patients.
Lead researcher Richard Wilson said he hoped that in 5 to 20 years, decoding a patient’s cancer genome would consist of dropping a spot of blood onto a chip that slides into a desktop computer and getting back a report that suggests which drugs will work best.“That’s personalized genomics, personalized medicine in a box,” he said. “It’s holy grail sort of stuff, but I think it’s not out of the realm of possibility” [The New York Times].