The image represents an artistic coloration of a cluster of circulating tumor cells (CTCs), isolated from the blood of a patient with breast cancer, trapped on a microfluidic device. © M Oeggerli / Micronaut 2018, supported by Pathology-, C-CINA / Biozentrum-, and I Krol, and N Aceto, Faculty of Medicine-, University Hospital and University Basel.

The most deadly aspect of breast cancer is metastasis. It spreads cancer cells throughout the body. Researchers at the University and the University Hospital of Basel have now discovered a substance that suppresses the formation of metastases. In the journal Cell, the team of molecular biologists, computational biologists, and clinicians reports on their interdisciplinary approach. The development of metastasis is responsible for more than 90% of cancer-related deaths, and patients with a metastatic disease are considered incurable.

Small intestine mucosa, shown here with 400x magnification under the microscope. Cells of the intestinal mucosa (intestinal epithelial cells) - marked in red - develop DNA damage, because the repair enzyme RNase H2b is absent. Photo: Konrad Aden/IKMB

A study by the Cluster of Excellence "Inflammation at Interfaces" finds a new mechanism by which DNA repair protects the genome and prevents the development of bowel cancer. Cancer is caused by the body's own cells, which change and start growing out of control. With bowel cancer, this affects the cells of the intestinal mucosa. The starting point are mutations, i.e. changes in the genetic information (DNA) of the intestinal stem cells. Their task is to regularly renew the cells of the intestinal mucosa. Intestinal stem cells must retain their ability to divide for their entire lifetime, and are thus particularly susceptible to mutations.

The Gram-negative Klebsiella pneumoniae bacterium often becomes resistant to common antibiotics. NIAID/CC BY 2.0

Many common antibiotics are increasingly losing their effectiveness against multi-resistant pathogens, which are becoming ever more prevalent. Bacteria use natural means to acquire mechanisms that protect them from harmful substances. For instance against the agent albicidin: Harmful Gram-negative bacteria possess a protein that binds and inactivates albicidin. The underlying resistance mechanism has been investigated at atomic resolution by scientists from the Helmholtz Centre for Infection Research (HZI) and the associated Helmholtz Institute for Pharmaceutical Research Saarland (HIPS).

On the left, an expanded human cell with microtubules (blue) and a pair of centrioles (yellow-red) in the middle. On the right the detailed structure of two expanded pairs of centrioles. Picture: Fabian Zwettler / University of Würzburg

Does expansion microscopy deliver true-to-life images of cellular structures? That was not sure yet. A new publication in "Nature Methods" shows for the first time that the method actually works reliably. 

Immersing deeper and deeper into cells with the microscope. Imaging the nucleus and other structures more and more accurately. Getting the most detailed views of cellular multi-protein complexes. All of these are goals pursued by the microscopy expert Markus Sauer at the Biocenter of Julius-Maximilians-Universität Würzburg (JMU) in Bavaria, Germany. Together with researchers from Geneva and Lausanne in Switzerland, he has now shown that a hitherto doubted method of super-resolution microscopy is reliable.