OTUD6B regulates KIFC1-dependent centrosome clustering and breast cancer cell survival.

Cancer cells often display centrosome amplification, requiring the kinesin KIFC1/HSET for centrosome clustering to prevent multipolar spindles and cell death. In parallel siRNA screens of deubiquitinase enzymes, we identify OTUD6B as a positive regulator of KIFC1 expression that is required for centrosome clustering in triple-negative breast cancer (TNBC) cells. OTUD6B can localise to centrosomes and the mitotic spindle and interacts with KIFC1.

RAFT solution polymerisation of bio-based γ-methyl-α-methylene-γ-butyrolactone monomer in DMSO and Cyrene.

Reversible addition fragmentation chain transfer (RAFT) solution polymerisation of the bio-based lactone monomer γ-methyl-α-methylene-γ-butyrolactone (γMeMBL) has been demonstrated in DMSO and Cyrene. RAFT control was evidenced by control over molecular weights, low disperisites, and kinetic evaluation. Purified P(γMeMBL) homopolymers exhibited high glass transition temperatures (206-221 °C) and excellent thermal stabilities.

Near millimolar concentration of nucleosomes in mitotic chromosomes from late prometaphase into anaphase.

Chromosome compaction is a key feature of mitosis and critical for accurate chromosome segregation. However, a precise quantitative analysis of chromosome geometry during mitotic progression is lacking. Here, we use volume electron microscopy to map, with nanometer precision, chromosomes from prometaphase through telophase in human RPE1 cells.

Rules of engagement for condensins and cohesins guide mitotic chromosome formation.

During mitosis, interphase chromatin is rapidly converted into rod-shaped mitotic chromosomes. Using Hi-C, imaging, proteomics and polymer modeling, we determine how the activity and interplay between loop-extruding SMC motors accomplishes this dramatic transition. Our work reveals rules of engagement for SMC complexes that are critical for allowing cells to refold interphase chromatin into mitotic chromosomes.

Ras protein abundance correlates with Ras isoform mutation patterns in cancer.

Activating mutations of Ras genes are often observed in cancer. The protein products of the three Ras genes are almost identical. However, for reasons that remain unclear, KRAS is far more frequently mutated than the other Ras isoforms in cancer and RASopathies.

Combinatorial approaches for mitigating resistance to KRAS-targeted therapies.

Approximately 15% of all cancer patients harbor mutated KRAS. Direct inhibitors of KRAS have now been generated and are beginning to make progress through clinical trials. These include a suite of inhibitors targeting the KRASG12C mutation commonly found in lung cancer.

Novel roles of RTN4 and CLIMP-63 in regulating mitochondrial structure, bioenergetics and apoptosis.

The recruitment of DRP1 to mitochondrial membranes prior to fission is facilitated by the wrapping of endoplasmic reticulum (ER) membranes around the mitochondria. To investigate the complex interplay between the ER membranes and DRP1 in the context of mitochondrial structure and function, we downregulate two key ER shaping proteins, RTN4 and CLIMP-63, and demonstrate pronounced mitochondrial hyperfusion and reduced ER-mitochondria contacts, despite their differential regulation of ER architecture. Although mitochondrial recruitment of DRP1 is unaltered in cells lacking RTN4 or CLIMP-63, several aspects of mitochondrial function, such as mtDNA-encoded translation, respiratory capacity and apoptosis are significantly hampered.

Carcinogen-induced DNA structural distortion differences in the RAS gene isoforms; the importance of local sequence.

Background: Local sequence context is known to have an impact on the mutational pattern seen in cancer. The RAS genes and a smoking carcinogen, Benzo[a]pyrene diol epoxide (BPDE), have been utilised to explore these context effects. BPDE is known to form an adduct at the guanines in a number of RAS gene sites, KRAS codons 12, 13 and 14, NRAS codon 12, and HRAS codons 12 and 14.

Kinobead Profiling Reveals Reprogramming of BCR Signaling in Response to Therapy within Primary CLL Cells.

Purpose: B-cell receptor (BCR) signaling is critical for the pathogenesis of chronic lymphocytic leukemia (CLL), promoting both malignant cell survival and disease progression. Although vital, understanding of the wider signaling network associated with malignant BCR stimulation is poor. This is relevant with respect to potential changes in response to therapy, particularly involving kinase inhibitors.

One-step preparation of antimicrobial silicone materials based on PDMS and salicylic acid: insights from spatially and temporally resolved techniques.

In this work, we introduce a one-step strategy that is suitable for continuous flow manufacturing of antimicrobial PDMS materials. The process is based on the intrinsic capacity of PDMS to react to certain organic solvents, which enables the incorporation of antimicrobial actives such as salicylic acid (SA), which has been approved for use in humans within pharmaceutical products. By combining different spectroscopic and imaging techniques, we show that the surface properties of PDMS remain unaffected while high doses of the SA are loaded inside the PDMS matrix.

Danger zone.

What level of Ras genes activity leads to the development of cancer?

Absolute Quantitation of GTPase Protein Abundance.

Ras proteins and other small molecular weight GTPases are molecular switches controlling a wide range of cellular functions. High homology and functional redundancy between closely related family members are commonly observed. Antibody-based methods are commonly used to characterize their protein expression.

Ras Variant Biology and Contributions to Human Disease.

Analysis of cancer and RASopathy genetic databases reveals that ~19% of all cancer cases and ~4% of developmental disorders contain Ras mutations. Ras isoform and mutation variants differentially contribute to these diseases and provide an opportunity for deeper understanding of Ras function. The putative mechanisms underpinning these differences, new approaches that are being applied, and some of the key questions and challenges that remain are discussed.

The importance of Ras in drug resistance in cancer.

In this review, we analyse the impact of oncogenic Ras mutations in mediating cancer drug resistance and the progress made in the abrogation of this resistance, through pharmacological targeting. At a physiological level, Ras is implicated in many cellular proliferation and survival pathways. However, mutations within this small GTPase can be responsible for the initiation of cancer, therapeutic resistance and failure, and ultimately disease relapse.

Structural insights into loss of function of a pore forming toxin and its role in pneumococcal adaptation to an intracellular lifestyle.

The opportunistic pathogen Streptococcus pneumoniae has dual lifestyles: one of an asymptomatic colonizer in the human nasopharynx and the other of a deadly pathogen invading sterile host compartments. The latter triggers an overwhelming inflammatory response, partly driven via pore forming activity of the cholesterol dependent cytolysin (CDC), pneumolysin. Although pneumolysin-induced inflammation drives person-to-person transmission from nasopharynx, the primary reservoir for pneumococcus, it also contributes to high mortality rates, creating a bottleneck that hampers widespread bacterial dissemination, thus acting as a double-edged sword.

Exploring High Aspect Ratio Gold Nanotubes as Cytosolic Agents: Structural Engineering and Uptake into Mesothelioma Cells.

The generation of effective and safe nanoagents for biological applications requires their physicochemical characteristics to be tunable, and their cellular interactions to be well characterized. Here, the controlled synthesis is developed for preparing high-aspect ratio gold nanotubes (AuNTs) with tailorable wall thickness, microstructure, composition, and optical characteristics. The modulation of optical properties generates AuNTs with strong near infrared absorption.

Trypanosoma brucei colonizes the tsetse gut via an immature peritrophic matrix in the proventriculus.

The peritrophic matrix of blood-feeding insects is a chitinous structure that forms a protective barrier against oral pathogens and abrasive particles. Tsetse flies transmit Trypanosoma brucei, which is the parasite that causes human sleeping sickness and is also partially responsible for animal trypanosomiasis in Sub-Saharan Africa. For this parasite to establish an infection in flies, it must first colonize the area between the peritrophic matrix and gut epithelium called the ectoperitrophic space.

The Frequency of Ras Mutations in Cancer.

Ras is frequently mutated in cancer, however, there is a lack of consensus in the literature regarding the cancer mutation frequency of Ras, with quoted values varying from 10%-30%. This variability is at least in part due to the selective aggregation of data from different databases and the dominant influence of particular cancer types and particular Ras isoforms within these datasets. To provide a more definitive figure for Ras mutation frequency in cancer, we cross-referenced the data in all major publicly accessible cancer mutation databases to determine reliable mutation frequency values for each Ras isoform in all major cancer types.

Exploiting Covalent, H-Bonding, and π-π Interactions to Design Antibacterial PDMS Interfaces That Load and Release Salicylic Acid.

Smart antimicrobial surfaces are a powerful tool to prevent bacterial colonization at surfaces. In this work, we report a successful strategy for the functionalization of polydimethylsiloxane (PDMS) surfaces, widely used in medical devices, with salicylic acid (SA), a biocide approved for use in humans. Antimicrobial PDMS surfaces were fabricated via a rational design in which bifunctional silane linker molecules were covalently grafted onto the PDMS via one end, while soft intermolecular interactions with SA were generated at the other end to enable reversible load and release of the biocide.

LAP-like non-canonical autophagy and evolution of endocytic vacuoles in pancreatic acinar cells.

Unlabelled: Activation of trypsinogen (formation of trypsin) inside the pancreas is an early pathological event in the development of acute pancreatitis. In our previous studies we identified the activation of trypsinogen within endocytic vacuoles (EVs), cellular organelles that appear in pancreatic acinar cells treated with the inducers of acute pancreatitis. EVs are formed as a result of aberrant compound exocytosis and subsequent internalization of post-exocytic structures.

ER stress-linked autophagy stabilizes apoptosis effector PERP and triggers its co-localization with SERCA2b at ER-plasma membrane junctions.

Specific molecular interactions that underpin the switch between ER stress-triggered autophagy-mediated cellular repair and cellular death by apoptosis are not characterized. This study reports the unexpected interaction elicited by ER stress between the plasma membrane (PM)-localized apoptosis effector PERP and the ER Ca pump SERCA2b. We show that the p53 effector PERP, which specifically induces apoptosis when expressed above a threshold level, has a heterogeneous distribution across the PM of un-stressed cells and is actively turned over by the lysosome.

Targeting centrosome amplification, an Achilles' heel of cancer.

Due to cell-cycle dysregulation, many cancer cells contain more than the normal compliment of centrosomes, a state referred to as centrosome amplification (CA). CA can drive oncogenic phenotypes and indeed can cause cancer in flies and mammals. However, cells have to actively manage CA, often by centrosome clustering, in order to divide.

Concentric lamellae - novel microanatomical structures in the articular calcified cartilage of mice.

The structure, ultrastructure and function of hyaline articular cartilage (HAC) and subchondral bone (SCB), and their involvement in the pathogenesis of osteoarthritis (OA) have been extensively researched. However, much less attention has been focused on the intervening tissue, articular calcified cartilage (ACC) and its role in the initiation and progression of OA. Using both light microscopy (LM) and transmission electron microscopy (TEM), a study of ACC in wild type (WT) mice, and mice with genetic osteoarthropathies (AKU) was undertaken to further understand the role played by ACC in the early stages of OA.

DRP-1 functions independently of mitochondrial structural perturbations to facilitate BH3 mimetic-mediated apoptosis.

Maintenance of mitochondrial integrity is critical for normal cellular homoeostasis. Most cells respond to stress stimuli and undergo apoptosis by perturbing mitochondrial structure and function to release proteins, such as cytochrome , which are essential for the execution of the intrinsic apoptotic cascade. Cancer cells evade these events by overexpressing the anti-apoptotic BCL-2 family of proteins on mitochondrial membranes.