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Epigenetic Strategy Restores Tumor Suppressor in Acute Myeloid Leukemia Models

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Scientists from The Jackson Laboratory (JAX) and their collaborators elsewhere have found a potential way to treat cases of acute myeloid leukemia that involves turning a key cancer fighting gene back on. Besides potentially treating AML without harsh chemotherapy regimens, their work also highlights a promising strategy for studying gene-silencing mechanisms in other diseases. Full details of the study, which was done in mice, are available in a paper published in Science Translational Medicine titled “Epigenetic reactivation of the tumor suppressor ZBTB7A by KDM4 inhibition in human acute myeloid leukemia.”

Normally, tumor suppressor genes work to prevent cells from becoming cancerous. But in cancers like AML, some of these genes are switched off epigenetically. These changes to gene activity are difficult to track because standard DNA sequencing technologies are designed to find mutated DNA. “If we can identify which genes have been silenced and understand how to turn them back on, that could open up entirely new therapeutic possibilities,” said Eric Wang, PhD, an assistant professor JAX who led the research. “Instead of only trying to kill these cells, we may be able to restore the mechanisms that normally keep them under control.”

Though scientists have made great strides in developing therapies for AML, prognosis for the disease is still relatively poor. Part of the challenge is that AML cells remain in an immature, stem cell-like state. According to the paper, Wang and his team developed a tool that combines fluorescence in situ hybridization and flow cytometry with CRISPR gene editing technology to map gene activity in cells. They used the tool, called FISHnCRISP, to identify a tumor-suppressing gene called ZBTB7A that is silenced in AML patients. By restoring ZBTB7A expression, the scientists forced the cancer cells into a state where they grew less aggressively.

Digging into the details, AML cells produce a longer version of ZBTB7A’s regulatory tail, that contains sites that attract a protein called ZFP36L2, which reduces the gene’s activity. Additionally, a family of enzymes known as KDM4 modify how DNA is packaged inside AML cells, which effectively silences ZBTB7A expression. Data from experiments in mice with AML showed that when KDM4 enzymes were blocked, ZBTB7A regained its expression, reducing leukemia burden while leaving normal blood formation largely unaffected.

Importantly, “there are drug candidates out there to inhibit KDM4, and in our study we just repurposed one of them to treat AML cells,” Wang said. “We won’t know unless we test it in clinical trials, but this approach could be better than chemotherapy, because we showed it’s not toxic at all to normal blood cells.” 

Future studies will focus on refining the approach and determining whether it might be combined with existing treatments. The team plans to test an experimental drug that targets KDM4, which is currently being tested in a clinical trial for solid tumors. 

“We demonstrated that downregulating ZBTB7A causes this hyperinflammatory state that promotes cancer growth” and “now, we’re proposing this epigenetic approach to force AML cells to differentiate into white blood cells that eventually undergo cell death,” Wang said. “We could potentially translate our research into an early phase clinical trial more readily than developing a whole new compound from scratch.” 

The post Epigenetic Strategy Restores Tumor Suppressor in Acute Myeloid Leukemia Models appeared first on GEN – Genetic Engineering and Biotechnology News.

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STAT+: At hospital finance conference, a call to end the friction that’s keeping costs high

NATIONAL HARBOR, Md. — At this week’s annual meeting of hospital finance leaders, the exhibit hall was packed with dozens of billing and collections companies. Armed with candy, tote bags, and pens, they smiled at passersby, eager to explain why their tactics would extract the most money from health insurers. 

The sheer number of “revenue cycle” vendors who attended the Healthcare Financial Management Association’s annual conference in Maryland — outnumbering even the hospital attendees, according to a list shared by an organizer — was a visible reminder of the enormous industry built around just paying medical bills. 

The U.S. health care industry spends roughly $200 billion annually on financial transactions: claims processing, payment, collections, and prior authorization. And yet the proliferation of billing vendors seemed to clash with the main theme of HFMA’s conference, affordability, spotlighting the need to simplify the billing process so that health care is less costly and more accessible for patients. 

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NATIONAL HARBOR, Md. — At this week’s annual meeting of hospital finance leaders, the exhibit hall was packed with dozens of billing and collections companies. Armed with candy, tote bags, and pens, they smiled at passersby, eager to explain why their tactics would extract the most money from health insurers. 

The sheer number of “revenue cycle” vendors who attended the Healthcare Financial Management Association’s annual conference in Maryland — outnumbering even the hospital attendees, according to a list shared by an organizer — was a visible reminder of the enormous industry built around just paying medical bills. 

The U.S. health care industry spends roughly $200 billion annually on financial transactions: claims processing, payment, collections, and prior authorization. And yet the proliferation of billing vendors seemed to clash with the main theme of HFMA’s conference, affordability, spotlighting the need to simplify the billing process so that health care is less costly and more accessible for patients. 

Continue to STAT+ to read the full story…

Read More

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Beyond sunshine: Iberia’s biotech moment has arrived with developing capital networks

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Strong science, lower costs and growing capital networks are putting Spain and Portugal on the biotech investment map, even as structural bottlenecks persist, according to two investors.

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Laser‑Driven Phase Contrast Enhances Cryo‑EM Resolution of Small Proteins

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You know when you are at the eye doctor getting an updated prescription, and suddenly the world snaps into sharper focus? Physicists at the University of California (UC), Berkeley, have now done something similar for electron microscopy. By introducing phase contrast into a cryo‑electron microscope, they have delivered dramatically sharper images of some of biology’s smallest and most elusive proteins.

The advance comes from a new laser phase plate (LPP), described in the paper “Laser phase plate improves structure determination of small proteins by cryo‑EM,” which was published recently in Science. Led by physicist Holger Mueller, PhD, of UC Berkeley and Lawrence Berkeley National Laboratory, the team demonstrated that a laser‑driven phase plate can overcome one of cryo‑EM’s most persistent limitations: poor contrast for small proteins.

Cryo-EM images of two proteins, apoferritin and hemoglobin, taken without and with a laser phase plate. The images are analyzed in a computer to produce detailed 3D structures of the proteins. [Holger Müller, Jessie Zhang/UC Berkeley]

Cryo‑EM has transformed structural biology over the past decade, earning a Nobel Prize in 2017 for enabling high‑resolution structures without crystallization. But despite its impact, the technique still struggles with proteins below ~70 kilodaltons—a size range that includes about 90% of the human proteome. “Because of signal-to-noise limitations, the majority of human and animal proteins are too small to be analyzed by these methods [cryo-EM and cryoelectron tomography]. The increase in signal-to-noise ratio provided by this laser phase plate is expected to overcome these important limitations.”

The new LPP begins to address that problem. The LPP uses an intense, continuous‑wave laser to shift the phase of the electron beam itself. This produces true phase contrast without dimming or destabilizing the beam. Mueller described the laser focus as “75 kilowatts focused to a few microns… That’s more powerful than what you use for welding. It has more power than a military laser. It builds up the brightest continuous laser focus ever.”

Installed in a custom Thermo Fisher Titan Krios, the LPP immediately improved the clarity and resolvability of small proteins, including hemoglobin, which sits at the lower limit of what today’s cryo‑EM instruments can handle. As the authors wrote in the abstract: “Here, we show that the laser phase plate (LPP)… enhances the resolution in single-particle reconstruction of small proteins by improving specimen-motion correction, recovery of information from the early frames, as well as particle visualization, 3D classification, and alignment.”

phase plate cover Cryo-EM
A laser (purple) is powerfully amplified by highly polished mirrors and focused on the electron beam (blue) to shift its phase and increase the cryo-EM microscope’s contrast, allowing biologists to image smaller proteins and the crowded structures inside cells. [Sayo Studio]

These improvements were achieved using standard defocus ranges and reconstruction workflows. “For the most challenging cases—small particles, bad specimens—the laser produces a very considerable advantage,” Mueller said.

 

The impact extends beyond single‑particle analysis. Cryo‑electron tomography (cryo‑ET), which assembles multiple angular views of a molecule or protein into a three-dimensional image, stands to benefit even more. “With cryo-ET, we’re looking at small, very complicated cellular material that’s incredibly crowded inside the cell,” said Bridget Carragher, PhD, founding technical director of imaging at Biohub. “It’s like a forest of trees, and you’re trying to find one leaf on one tree in there. Cryo-ET needs a dramatic step forward in contrast, so we can start to see what’s going on inside the cell. That’s what the laser phase plate promises to give us.”

Biohub is developing a dual‑laser version of the system, designed to reduce component wear and minimize aberrations. Meanwhile, Mueller’s team is pushing toward imaging proteins as small as 17 kilodaltons, a threshold that would open access to vast regions of the human proteome previously invisible to cryo‑EM.

“This technology is a step function change for biology,” said Stephani Otte, PhD, Biohub’s vice president of imaging science. “What was once invisible will become visible—and that changes everything about how we understand disease.”

“The bottom line is, if you have a large protein and a really good sample—a fresh one or one frozen without bubbles, for example—you may not need the phase plate to get a single, high-quality image. But for a small protein and a bad sample, laser-on is best,” Mueller said. “This could fill an enormous gap in our knowledge of protein structures that can’t be crystallized or are too small for today’s cryo-EM. And it will be revolutionary for cryo-ET.”

The post Laser‑Driven Phase Contrast Enhances Cryo‑EM Resolution of Small Proteins appeared first on GEN – Genetic Engineering and Biotechnology News.

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