Warren symposium follows legacy of geneticist giant

If we want to understand how the brain creates memories, and how genetic disorders distort the brain’s machinery, then the fragile X gene is an ideal place to start. That’s why the Stephen T. Warren Memorial Symposium, taking place November 28-29 at Emory, will be a significant event for those interested in neuroscience and genetics. Stephen T. Warren, 1953-2021 Warren, the founding chair of Emory’s Department of Human Genetics, led an international team that discovered Read more

Mutations in V-ATPase proton pump implicated in epilepsy syndrome

Why and how disrupting V-ATPase function leads to epilepsy, researchers are just starting to figure Read more

Tracing the start of COVID-19 in GA

At a time when COVID-19 appears to be receding in much of Georgia, it’s worth revisiting the start of the pandemic in early 2020. Emory virologist Anne Piantadosi and colleagues have a paper in Viral Evolution on the earliest SARS-CoV-2 genetic sequences detected in Georgia. Analyzing relationships between those virus sequences and samples from other states and countries can give us an idea about where the first COVID-19 infections in Georgia came from. We can draw Read more
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brain tumor

Progesterone could become tool vs glioblastoma

The hormone progesterone could become part of therapy against the most aggressive form of brain cancer. High concentrations of progesterone kill glioblastoma cells and inhibit tumor growth when the tumors are implanted in mice, researchers have found.

The results were recently published in the Journal of Steroid Biochemistry and Molecular Biology.

Glioblastoma is the most common and the most aggressive form of brain cancer in adults, with average survival after diagnosis of around 15 months. Surgery, radiation and chemotherapy do prolong survival by several months, but targeted therapies, which have been effective with other forms of cancer, have not lengthened survival in patients fighting glioblastoma.

The lead author of the current paper is assistant professor of emergency medicine Fahim Atif, PhD. The findings with glioblastoma came out of Emory researchers’ work on progesterone as therapy for traumatic brain injury and more recently, stroke. Atif, Donald Stein and their colleagues have been studying progesterone for the treatment of traumatic brain injury for more than two decades, prompted by Stein’s initial observation that females recover from brain injury more readily than males. There is a similar tilt in glioblastoma as well: primary glioblastoma develops three times more frequently in males compared to females.

These results could pave the way for the use of progesterone against glioblastoma in a human clinical trial, perhaps in combination with standard-of-care therapeutic agents such as temozolomide. However, Stein says that more experiments are necessary with grafts of human tumor cells into animal brains first. His team identified a factor that may be important for clinical trial design: progesterone was not toxic to all glioblastoma cell lines, and its toxicity may depend on whether the tumor suppressor gene p53 is mutated.

Atif, Stein, and colleague Seema Yousuf found that low, physiological doses of progesterone stimulate the growth of glioblastoma tumor cells, but higher doses kill the tumor cells while remaining nontoxic for healthy cells. Similar effects have been seen with the progesterone antagonist RU486, but the authors cite evidence that progesterone is less toxic to healthy cells. Progesterone has also been found to inhibit growth of neuroblastoma cells (neuroblastoma is the most common cancer in infants), as well as breast, ovarian and colon cancers in cell culture and animal models.

 

Posted on May 14, 2014 by Quinn Eastman in Cancer, Neuro Leave a comment

High-contrast brain tumor imaging

This month’s intriguing images come from radiation oncologist Ian Crocker and colleagues. Each one shows a patient with a glioblastoma, an aggressive brain tumor. The patient’s brain was scanned in two ways: on the left, MRI (magnetic resonance imaging) and on the right, PET (positron emission tomography), using a probe developed at Emory. We can see that the tumor’s PET signal is more distinct than the tumor’s appearance on MRI.

Since the 1990s, Mark Goodman, John Votaw and colleagues at Emory’s Center for Systems Imaging have been developing the probe FACBC (fluoro-1-amino-3-cyclobutyl carboxylic acid) as a probe for the detection of tumors.

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Posted on October 9, 2013 by Quinn Eastman in Cancer Leave a comment

Blocking glioblastoma escape

Treatment strategies for several types of cancer have been transformed by the discovery of “targeted therapies,” drugs directed specifically against the genetic mutations that drive tumor growth. So far, these strategies have been relatively unsuccessful when it comes to glioblastoma, the most common and most deadly form of brain tumor affecting adults. Glioblastoma was one of the first tumor types to be analyzed in the Cancer Genome Atlas mega-project, but many of the molecular features of glioblastoma have been difficult to exploit.

For example, about 40 percent of glioblastoma tumors ray ban baratas have extra copies of the EGFR (epidermal growth factor receptor) gene. EGFR provides a pedal-to-the-metal growth signal and is known to play a role in driving the growth of lung and colon cancers as well. But drugs targeted against EGFR that have extended patient survival in lung cancer have shown disappointing results with glioblastoma. The reason: the tumor cells can quickly mutate the EGFR gene or switch to reliance on other growth signals.

Keqiang Ye, PhD and colleagues recently described the discovery of a compound that may be valuable in fighting glioblastoma. The Emory researchers devised a scheme to stop tumor cells from using well-known escape routes to avoid EGFR-based drugs. Their results are published in the journal Science Signaling. Postdoctoral fellow Kunyan He, PhD, is the first author.

The compound they identified inhibits the enzyme JAK2, one of the apparent escape Ray Ban outlet routes taken by glioblastoma cells. The compound can pass the blood-brain barrier and inhibit glioblastoma growth while having low toxicity, the researchers report.

Posted on July 23, 2013 by Quinn Eastman in Cancer 1 Comment