The MondoA-dependent TXNIP/GDF15 axis predicts oxaliplatin response in colorectal adenocarcinomas.

Chemotherapy, the standard of care treatment for cancer patients with advanced disease, has been increasingly recognized to activate host immune responses to produce durable outcomes. Here, in colorectal adenocarcinoma (CRC) we identify oxaliplatin-induced Thioredoxin-Interacting Protein (TXNIP), a MondoA-dependent tumor suppressor gene, as a negative regulator of Growth/Differentiation Factor 15 (GDF15). GDF15 is a negative prognostic factor in CRC and promotes the differentiation of regulatory T cells (Tregs), which inhibit CD8 T-cell activation.

Osimertinib and anti-HER3 combination therapy engages immune dependent tumor toxicity via STING activation in trans.

Over the past decade, immunotherapy delivered novel treatments for many cancer types. However, lung cancer still leads cancer mortality, and non-small-cell lung carcinoma patients with mutant EGFR cannot benefit from checkpoint inhibitors due to toxicity, relying only on palliative chemotherapy and the third-generation tyrosine kinase inhibitor (TKI) osimertinib. This new drug extends lifespan by 9-months vs.

HER2 Mediates PSMA/mGluR1-Driven Resistance to the DS-7423 Dual PI3K/mTOR Inhibitor in PTEN Wild-type Prostate Cancer Models.

Prostate cancer remains a major cause of male mortality. Genetic alteration of the PI3K/AKT/mTOR pathway is one of the key events in tumor development and progression in prostate cancer, with inactivation of the PTEN tumor suppressor being very common in this cancer type. Extensive evaluation has been performed on the therapeutic potential of PI3K/AKT/mTOR inhibitors and the resistance mechanisms arising in patients with PTEN-mutant background.

Insights Into Unveiling a Potential Role of Tertiary Lymphoid Structures in Metastasis.

Tertiary lymphoid structures (TLSs) develop in non-lymphatic tissue in chronic inflammation and cancer. TLS can mature to lymph node (LN) like structures with germinal centers and associated vasculature. TLS neogenesis in cancer is highly varied and tissue dependent.

Integrin-Mediated Macrophage Adhesion Promotes Lymphovascular Dissemination in Breast Cancer.

Lymphatic vasculature is crucial for metastasis in triple-negative breast cancer (TNBC); however, cellular and molecular drivers controlling lymphovascular metastasis are poorly understood. We define a macrophage-dependent signaling cascade that facilitates metastasis through lymphovascular remodeling. TNBC cells instigate mRNA changes in macrophages, resulting in β4 integrin-dependent adhesion to the lymphovasculature.

ALIX Regulates Tumor-Mediated Immunosuppression by Controlling EGFR Activity and PD-L1 Presentation.

The immunosuppressive transmembrane protein PD-L1 was shown to traffic via the multivesicular body (MVB) and to be released on exosomes. A high-content siRNA screen identified the endosomal sorting complexes required for transport (ESCRT)-associated protein ALIX as a regulator of both EGFR activity and PD-L1 surface presentation in basal-like breast cancer (BLBC) cells. ALIX depletion results in prolonged and enhanced stimulation-induced EGFR activity as well as defective PD-L1 trafficking through the MVB, reduced exosomal secretion, and its redistribution to the cell surface.

RORγt Innate Lymphoid Cells Promote Lymph Node Metastasis of Breast Cancers.

Cancer cells tend to metastasize first to tumor-draining lymph nodes, but the mechanisms mediating cancer cell invasion into the lymphatic vasculature remain little understood. Here, we show that in the human breast tumor microenvironment (TME), the presence of increased numbers of RORγt group 3 innate lymphoid cells (ILC3) correlates with an increased likelihood of lymph node metastasis. In a preclinical mouse model of breast cancer, CCL21-mediated recruitment of ILC3 to tumors stimulated the production of the CXCL13 by TME stromal cells, which in turn promoted ILC3-stromal interactions and production of the cancer cell motile factor RANKL.

Lamellipodin promotes invasive 3D cancer cell migration via regulated interactions with Ena/VASP and SCAR/WAVE.

Cancer invasion is a hallmark of metastasis. The mesenchymal mode of cancer cell invasion is mediated by elongated membrane protrusions driven by the assembly of branched F-actin networks. How deregulation of actin regulators promotes cancer cell invasion is still enigmatic.

c-Met PET Imaging Detects Early-Stage Locoregional Recurrence of Basal-Like Breast Cancer.

Unlabelled: Locoregional recurrence of breast cancer poses significant clinical problems because of frequent inoperability once the chest wall is involved. Early detection of recurrence by molecular imaging agents against therapeutically targetable receptors, such as c-Met, would be of potential benefit. The aim of this study was to assess (18)F-AH113804, a peptide-based molecular imaging agent with high affinity for human c-Met, for the detection of early-stage locoregional recurrence in a human basal-like breast cancer model, HCC1954.

A high speed multifocal multiphoton fluorescence lifetime imaging microscope for live-cell FRET imaging.

We demonstrate diffraction limited multiphoton imaging in a massively parallel, fully addressable time-resolved multi-beam multiphoton microscope capable of producing fluorescence lifetime images with sub-50ps temporal resolution. This imaging platform offers a significant improvement in acquisition speed over single-beam laser scanning FLIM by a factor of 64 without compromising in either the temporal or spatial resolutions of the system. We demonstrate FLIM acquisition at 500 ms with live cells expressing green fluorescent protein.

Tyrosine phosphorylation of WIP releases bound WASP and impairs podosome assembly in macrophages.

Podosomes are integrin-containing adhesion structures commonly found in migrating leukocytes of the monocytic lineage. The actin cytoskeletal organisation of podosomes is based on a WASP- and Arp2/3-mediated mechanism. WASP also associates with a second protein, WIP (also known as WIPF1), and they co-localise in podosome cores.

Steady-state acceptor fluorescence anisotropy imaging under evanescent excitation for visualisation of FRET at the plasma membrane.

We present a novel imaging system combining total internal reflection fluorescence (TIRF) microscopy with measurement of steady-state acceptor fluorescence anisotropy in order to perform live cell Förster Resonance Energy Transfer (FRET) imaging at the plasma membrane. We compare directly the imaging performance of fluorescence anisotropy resolved TIRF with epifluorescence illumination. The use of high numerical aperture objective for TIRF required correction for induced depolarization factors.

The ErbB4 CYT2 variant protects EGFR from ligand-induced degradation to enhance cancer cell motility.

The epidermal growth factor receptor (EGFR) is a member of the ErbB family that can promote the migration and proliferation of breast cancer cells. Therapies that target EGFR can promote the dimerization of EGFR with other ErbB receptors, which is associated with the development of drug resistance. Understanding how interactions among ErbB receptors alter EGFR biology could provide avenues for improving cancer therapy.

Vinculin binding angle in podosomes revealed by high resolution microscopy.

Podosomes are highly dynamic actin-rich adhesive structures formed predominantly by cells of the monocytic lineage, which degrade the extracellular matrix. They consist of a core of F-actin and actin-regulating proteins, surrounded by a ring of adhesion-associated proteins such as vinculin. We have characterised the structure of podosomes in macrophages, particularly the structure of the ring, using three super-resolution fluorescence microscopy techniques: stimulated emission depletion microscopy, structured illumination microscopy and localisation microscopy.

Megakaryocytes assemble podosomes that degrade matrix and protrude through basement membrane.

Megakaryocytes give rise to platelets via extension of proplatelet arms, which are released through the vascular sinusoids into the bloodstream. Megakaryocytes and their precursors undergo varying interactions with the extracellular environment in the bone marrow during their maturation and positioning in the vascular niche. We demonstrate that podosomes are abundant in primary murine megakaryocytes adherent on multiple extracellular matrix substrates, including native basement membrane.

Bayesian localization microscopy reveals nanoscale podosome dynamics.

We describe a localization microscopy analysis method that is able to extract results in live cells using standard fluorescent proteins and xenon arc lamp illumination. Our Bayesian analysis of the blinking and bleaching (3B analysis) method models the entire dataset simultaneously as being generated by a number of fluorophores that may or may not be emitting light at any given time. The resulting technique allows many overlapping fluorophores in each frame and unifies the analysis of the localization from blinking and bleaching events.

Tyrosine phosphorylation of WASP promotes calpain-mediated podosome disassembly.

Podosomes are actin-based adhesions involved in migration of cells that have to cross tissue boundaries such as myeloid cells. The Wiskott Aldrich Syndrome Protein regulates de novo actin polymerization during podosome formation and it is cleaved by the protease calpain during podosome disassembly. The mechanisms that may induce the Wiskott Aldrich Syndrome Protein cleavage by calpain remain undetermined.

A targeted siRNA screen identifies regulators of Cdc42 activity at the natural killer cell immunological synapse.

Natural killer (NK) cells kill tumor cells and virally infected cells, and an effective NK cell response requires processes, such as motility, recognition, and directional secretion, that rely on cytoskeletal rearrangement. The Rho guanosine triphosphatase (GTPase) Cdc42 coordinates cytoskeletal reorganization downstream of many receptors. The Rho-related GTPase from plants 1 (ROP1) exhibits oscillatory activation behavior at the apical plasma membrane of growing pollen tubes; however, a similar oscillation in Rho GTPase activity has so far not been demonstrated in mammalian cells.

β1 integrins regulate fibroblast chemotaxis through control of N-WASP stability.

Chemotactic migration of fibroblasts towards growth factors, such as during development and wound healing, requires precise spatial coordination of receptor signalling. However, the mechanisms regulating this remain poorly understood. Here, we demonstrate that β1 integrins are required both for fibroblast chemotaxis towards platelet-derived growth factor (PDGF) and growth factor-induced dorsal ruffling.

The cortactin-binding domain of WIP is essential for podosome formation and extracellular matrix degradation by murine dendritic cells.

In immature dendritic cells (DCs) podosomes form and turn over behind the leading edge of migrating cells. The Arp2/3 complex activator Wiskott-Aldrich Syndrome Protein (WASP) localises to the actin core of forming podosomes together with WASP-Interacting Protein (WIP). A second weaker Arp2/3 activator, cortactin, is also found at podosomes where it has been proposed to participate in matrix metalloproteinase (MMP) secretion.

Role of WASP in cell polarity and podosome dynamics of myeloid cells.

The integrin-dependent migration of myeloid cells requires tight coordination between actin-based cell membrane protrusion and integrin-mediated adhesion to form a stable leading edge. Under this mode of migration, polarised myeloid cells including dendritic cells, macrophages and osteoclasts develop podosomes that sustain the extending leading edge. Podosome integrity and dynamics vary in response to changes in the physical and biochemical properties of the cell environment.

Cdc42 and Rac family GTPases regulate mode and speed but not direction of primary fibroblast migration during platelet-derived growth factor-dependent chemotaxis.

Cdc42 and Rac family GTPases are important regulators of morphology, motility, and polarity in a variety of mammalian cell types. However, comprehensive analysis of their roles in the morphological and behavioral aspects of chemotaxis within a single experimental system is still lacking. Here we demonstrate using a direct viewing chemotaxis assay that of all of the Cdc42/Rac1-related GTPases expressed in primary fibroblasts, Cdc42, Rac1, and RhoG are required for efficient migration towards platelet-derived growth factor (PDGF).

The membrane-anchored metalloproteinase regulator RECK stabilizes focal adhesions and anterior-posterior polarity in fibroblasts.

Accumulating evidence indicates that Reversion-inducing cysteine-rich protein with Kazal motifs (RECK), a membrane-anchored matrix metalloproteinase regulator, plays crucial roles in mammalian development and tumor suppression. Its mechanisms of action at the single cell level, however, remain largely unknown. In mouse fibroblasts, RECK is abundant around the perinuclear region, membrane ruffles and cell surface.

G-actin regulates rapid induction of actin nucleation by mDia1 to restore cellular actin polymers.

mDia1 belongs to the formin family of proteins that share FH1 and FH2 domains. Although formins play a critical role in the formation of many actin-based cellular structures, the physiological regulation of formin-mediated actin assembly within the cell is still unknown. Here we show that cells possess an acute actin polymer restoration mechanism involving mDia1.

The Rho-mDia1 pathway regulates cell polarity and focal adhesion turnover in migrating cells through mobilizing Apc and c-Src.

Directed cell migration requires cell polarization and adhesion turnover, in which the actin cytoskeleton and microtubules work critically. The Rho GTPases induce specific types of actin cytoskeleton and regulate microtubule dynamics. In migrating cells, Cdc42 regulates cell polarity and Rac works in membrane protrusion.