Two items relevant to long COVID

One of the tricky issues in studying in long COVID is: how widely do researchers cast their net? Initial reports acknowledged that people who were hospitalized and in intensive care may take a while to get back on their feet. But the number of people who had SARS-CoV-2 infections and were NOT hospitalized, yet experienced lingering symptoms, may be greater. A recent report from the United Kingdom, published in PLOS Medicine, studied more than Read more

All your environmental chemicals belong in the exposome

Emory team wanted to develop a standard low-volume approach that would avoid multiple processing steps, which can lead to loss of material, variable recovery, and the potential for Read more

Signature of success for an HIV vaccine?

Efforts to produce a vaccine against HIV/AIDS have been sustained for more than a decade by a single, modest success: the RV144 clinical trial in Thailand, whose results were reported in 2009. Now Emory, Harvard and Case Western Reserve scientists have identified a gene activity signature that may explain why the vaccine regimen in the RV144 study was protective in some individuals, while other HIV vaccine studies were not successful. The researchers think that this signature, Read more

metastasis

Invasive lung cancer cells have distinct roles

When cancer cells split off from a tumor to seed deadly metastases, they are thought to travel as clusters or packs, a phenomenon known as collective invasion. The members of an invasive pack are not all alike, scientists at Winship Cancer Institute of Emory University have learned.

Lung cancer cells making up an invasive pack have specialized roles as leaders and followers, which depend on each other for mobility and survival, the scientists report in Nature Communications.

The differences between leaders and followers — and their interdependence — could be keys for future treatments aimed at impairing or preventing cancer metastasis, says senior author Adam Marcus, PhD, associate professor of hematology and medical oncology at Winship Cancer Institute and Emory University School of Medicine.

“We’re finding that leader and follower cells have a symbiotic relationship and depend on each for survival and invasion,” he says. “Because metastatic invasion is the deadliest aspect of cancer, our goal is to find agents that disrupt that symbiotic relationship.”

Marcus and former graduate student Jessica Konen, PhD began by observing how a mass of lung cancer cells behaves when embedded in a 3-D protein gel. The cells generally stick together, but occasionally, a few cells extend out of the mass like tentacles, with the leader cell at the tip.

“We saw that when the leader cell became detached or died unexpectedly, the followers could no longer move,” says Konen, now a postdoctoral fellow at MD Anderson. “In one particular movie, we saw a leader cell come out away from the rest of the cells, and then seem to realize that nobody was following him. He actually did a 180, and went back to grab cells to bring with him.” Read more

Posted on by Quinn Eastman in Cancer 1 Comment

Lung cancer cells go amoeboid

Cancer biologists Jessica Konen and Scott Wilkinson, in Adam Marcus’ lab, recently published a paper on the function of LKB1, a gene that is often mutated in lung cancer cells. [Number three behind K-ras and p53.]

Amoeboid

Mesenchymal shape is defined as having a length more than twice the width. Amoeboid looks more like the cell on the right: rounded up. Thanks to Jessica Konen for photo.

Konen and Marcus were featured in a prize-winning video that our team produced last year, which discusses how they developed a technique for isolating “leader cells” — lung cancer cells that migrate and invade more quickly — from a large group and studying those cells’ properties more intensively.

The Molecular Biology of the Cell paper covers a related topic: how LKB1 mutation affects cell shape. In particular, losing LKB1 converts lung cancer cells from a “mesenchymal” morphology to an “amoeboid” morphology.  Read more

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Stop the blob!

For your viewing pleasure, we have two videos, courtesy of Winship Cancer Institute’s Adam Marcus. He and his colleagues are investigating whether Withania somnifera, a root used in Indian traditional medicine, could be a source for drugs that inhibit breast cancer invasion and metastasis. Metastasis occurs when cells from a primary tumor migrate to a new location and invade the tissues at the new location.

The first video, the blob that grows, shows MCF10a mammary Ray Ban outlet epithelial cells undergoing epithelial-mesenchymal transition (EMT) in response to TGF-beta. This is a laboratory model for understanding breast cancer invasion and metastasis.

The second shows what happens when the same cells are treated with an extract from Withania somnifera. The blob doesn’t expand in such a threatening way anymore! The results were recently published in PLOS One.

 

Posted on by Quinn Eastman in Cancer Leave a comment