Phytochemical Profile and In Vitro Cytotoxic, Genotoxic, and Antigenotoxic Evaluation of L. Leaf Extract.

L. () is used in Italian folk medicine. This study was performed to determine genotoxic and antigenotoxic effects of leaf extract against mitomycin C (MMC) using an in vitro cytokinesis-block micronucleus assay (CBMN) in the Chinese Hamster Ovarian K1 (CHO-K1) cell line.

Selective delivery of G-quadruplex ligand in glioma cell lines: the power of cyclic-RGD peptide.

Compounds targeting non-canonical secondary structures of nucleic acids, known as G-quadruplexes, are highly cytotoxic, both for cancer and healthy cells, because of their action mechanism's lack of appropriate selectivity. The targeted delivery of cytotoxic molecules to cancer cells is a valuable strategy to expand the repertoire of potential drugs, especially for cancer types for which new therapeutic tools are urgently needed, like glioblastoma. In this work, we conjugated a cyclic arginyl-glycyl-aspartic acid peptide to a naphthalene diimide, previously described as a highly performing stabilizing ligand for DNA G-quadruplexes, to specifically target glioma cells overexpressing RGD-binding integrin receptors.

Cell stretching activates an ATM mechano-transduction pathway that remodels cytoskeleton and chromatin.

Ataxia telangiectasia mutated (ATM) and ataxia telangiectasia and Rad3-related (ATR) DNA damage response (DDR) kinases contain elastic domains. ATM also responds to reactive oxygen species (ROS) and ATR to nuclear mechanical stress. Mre11 mediates ATM activation following DNA damage; ATM mutations cause ataxia telangiectasia (A-T).

Decellularized extracellular matrix as scaffold for cancer organoid cultures of colorectal peritoneal metastases.

Peritoneal metastases (PM) from colorectal cancer (CRC) are associated with poor survival. The extracellular matrix (ECM) plays a fundamental role in modulating the homing of CRC metastases to the peritoneum. The mechanisms underlying the interactions between metastatic cells and the ECM, however, remain poorly understood, and the number of in vitro models available for the study of the peritoneal metastatic process is limited.

Simultaneous Labeling of Adipogenic and Osteogenic Differentiating Stem Cells for Live Confocal Analysis.

Adipocytes and osteoblasts derive from a common mesenchymal progenitor present in a range of connective tissues. Differentiation of the progenitors toward the two cell lineages can be induced in vitro through well-established protocols, and leads to the appearance of lipid-laden adipocytes and osteoblasts embedded in a mineralized matrix. The formation of these two lineages in cell cultures can be monitored using lipophilic dyes such as Oil Red O and substances binding to mineral deposits such as Alizarin Red S, respectively.

Hecw controls oogenesis and neuronal homeostasis by promoting the liquid state of ribonucleoprotein particles.

Specialised ribonucleoprotein (RNP) granules are a hallmark of polarized cells, like neurons and germ cells. Among their main functions is the spatial and temporal modulation of the activity of specific mRNA transcripts that allow specification of primary embryonic axes. While RNPs composition and role are well established, their regulation is poorly defined.

IRSp53 controls plasma membrane shape and polarized transport at the nascent lumen in epithelial tubules.

It is unclear whether the establishment of apical-basal cell polarity during the generation of epithelial lumens requires molecules acting at the plasma membrane/actin interface. Here, we show that the I-BAR-containing IRSp53 protein controls lumen formation and the positioning of the polarity determinants aPKC and podocalyxin. Molecularly, IRSp53 acts by regulating the localization and activity of the small GTPase RAB35, and by interacting with the actin capping protein EPS8.

From injury to full repair: nerve regeneration and functional recovery in the common octopus, .

Spontaneous nerve regeneration in cephalopod molluscs occurs in a relative short time after injury, achieving functional recovery of lost capacity. In particular, transection of the pallial nerve in the common octopus () determines the loss and subsequent restoration of two functions fundamental for survival, i.e.

Redundant and nonredundant organismal functions of EPS15 and EPS15L1.

EPS15 and its homologous EPS15L1 are endocytic accessory proteins. Studies in mammalian cell lines suggested that EPS15 and EPS15L1 regulate endocytosis in a redundant manner. However, at the organismal level, it is not known to which extent the functions of the two proteins overlap.

Kinesin-2 Controls the Motility of RAB5 Endosomes and Their Association with the Spindle in Mitosis.

RAB5 is a small GTPase that belongs to the wide family of Rab proteins and localizes on early endosomes. In its active GTP-bound form, RAB5 recruits downstream effectors that, in turn, are responsible for distinct aspects of early endosome function, including their movement along microtubules. We previously reported that, at the onset of mitosis, RAB5positive vesicles cluster around the spindle poles and, during metaphase, move along spindle microtubules.

RAB2A controls MT1-MMP endocytic and E-cadherin polarized Golgi trafficking to promote invasive breast cancer programs.

The mechanisms of tumor cell dissemination and the contribution of membrane trafficking in this process are poorly understood. Through a functional siRNA screening of human RAB GTPases, we found that RAB2A, a protein essential for ER-to-Golgi transport, is critical in promoting proteolytic activity and 3D invasiveness of breast cancer (BC) cell lines. Remarkably, RAB2A is amplified and elevated in human BC and is a powerful and independent predictor of disease recurrence in BC patients.

DICER, DROSHA and DNA damage response RNAs are necessary for the secondary recruitment of DNA damage response factors.

The DNA damage response (DDR) plays a central role in preserving genome integrity. Recently, we reported that the endoribonucleases DICER and DROSHA contribute to DDR activation by generating small non-coding RNAs, termed DNA damage response RNA (DDRNA), carrying the sequence of the damaged locus. It is presently unclear whether DDRNAs act by promoting the primary recognition of DNA lesions or the secondary recruitment of DDR factors into cytologically detectable foci and consequent signal amplification.

NuMA Phosphorylation by Aurora-A Orchestrates Spindle Orientation.

Spindle positioning is essential for tissue morphogenesis and homeostasis. The signaling network synchronizing spindle placement with mitotic progression relies on timely recruitment at the cell cortex of NuMA:LGN:Gαi complexes, in which NuMA acts as a receptor for the microtubule motor Dynein. To study the implication of Aurora-A in spindle orientation, we developed protocols for the partial inhibition of its activity.

Lamellipodial tension, not integrin/ligand binding, is the crucial factor to realise integrin activation and cell migration.

The molecular clutch (MC) model proposes that actomyosin-driven force transmission permits integrin-dependent cell migration. To investigate the MC, we introduced diverse talin (TLN) and integrin variants into Flp-In™ T-Rex™ HEK293 cells stably expressing uPAR. Vitronectin variants served as substrate providing uPAR-mediated cell adhesion and optionally integrin binding.

A gut-vascular barrier controls the systemic dissemination of bacteria.

In healthy individuals, the intestinal microbiota cannot access the liver, spleen, or other peripheral tissues. Some pathogenic bacteria can reach these sites, however, and can induce a systemic immune response. How such compartmentalization is achieved is unknown.

Regulation of the microtubular cytoskeleton by Polycystin-1 favors focal adhesions turnover to modulate cell adhesion and migration.

Background: Polycystin-1 (PC-1) is a large plasma membrane receptor, encoded by the PKD1 gene, which is mutated in most cases of Autosomal Dominant Polycystic Kidney Disease (ADPKD). The disease is characterized by renal cysts. The precise function of PC-1 remains elusive, although several studies suggest that it can regulate the cellular shape in response to external stimuli.

The Mps1 kinase modulates the recruitment and activity of Cnn1(CENP-T) at Saccharomyces cerevisiae kinetochores.

Kinetochores are conserved protein complexes that bind the replicated chromosomes to the mitotic spindle and then direct their segregation. To better comprehend Saccharomyces cerevisiae kinetochore function, we dissected the phospho-regulated dynamic interaction between conserved kinetochore protein Cnn1(CENP-T), the centromere region, and the Ndc80 complex through the cell cycle. Cnn1 localizes to kinetochores at basal levels from G1 through metaphase but accumulates abruptly at anaphase onset.

Collective cell motility promotes chemotactic prowess and resistance to chemorepulsion.

Collective cell migration is a widespread biological phenomenon, whereby groups of highly coordinated, adherent cells move in a polarized fashion. This migration mode is a hallmark of tissue morphogenesis during development and repair and of solid tumor dissemination. In addition to circulating as solitary cells, lymphoid malignancies can assemble into tissues as multicellular aggregates.

The CDC42-interacting protein 4 controls epithelial cell cohesion and tumor dissemination.

The role of endocytic proteins and the molecular mechanisms underlying epithelial cell cohesion and tumor dissemination are not well understood. Here, we report that the endocytic F-BAR-containing CDC42-interacting protein 4 (CIP4) is required for ERBB2- and TGF-β1-induced cell scattering, breast cancer (BC) cell motility and invasion into 3D matrices, and conversion from ductal breast carcinoma in situ to invasive carcinoma in mouse xenograft models. CIP4 promotes the formation of an E-cadherin-CIP4-SRC complex that controls SRC activation, E-cadherin endocytosis, and localized phosphorylation of the myosin light chain kinase, thereby impinging on the actomyosin contractility required to generate tangential forces to break cell-cell junctions.

The GTPase-activating protein RN-tre controls focal adhesion turnover and cell migration.

Background: Integrin-mediated adhesion of cells to the extracellular matrix (ECM) relies on the dynamic formation of focal adhesions (FAs), which are biochemical and mechanosensitive platforms composed of a large variety of cytosolic and transmembrane proteins. During migration, there is a constant turnover of ECM contacts that initially form as nascent adhesions at the leading edge, mature into FAs as actomyosin tension builds up, and are then disassembled at the cell rear, thus allowing for cell detachment. Although the mechanisms of FA assembly have largely been defined, the molecular circuitry that regulates their disassembly still remains elusive.

Investigation of in vitro cytotoxicity of the redox state of ionic iron in neuroblastoma cells.

Background: there is an intimate relation between transition metals and cell homeostasis due to the physiological necessity of metals in vivo. Particularly, iron (ferrous and ferric state) is utilized in many physiological processes of the cell but in excess has been linked with negative role contributing in many neurodegenerative processes.

Objective: the aim of this study was to investigate which oxidation state of ionic iron (Ferrous (II) versus Ferric (III)) is more toxic to neuronal cells (SHSY(5)Y).

Cnn1 inhibits the interactions between the KMN complexes of the yeast kinetochore.

Kinetochores attach the replicated chromosomes to the mitotic spindle and orchestrate their transmission to the daughter cells. Kinetochore-spindle binding and chromosome segregation are mediated by the multi-copy KNL1(Spc105), MIS12(Mtw1) and NDC80(Ndc80) complexes that form the so-called KMN network. KMN-spindle attachment is regulated by the Aurora B(Ipl1) and MPS1(Mps1) kinases.

Small GTPase Rab5 participates in chromosome congression and regulates localization of the centromere-associated protein CENP-F to kinetochores.

Rab5 is a small GTPase known to regulate vesicular trafficking during interphase. Here, we show that Rab5 also plays an unexpected role during mitotic progression. RNAi-mediated silencing of Rab5 caused defects in chromosome congression and extensive prometaphase delay, and it correlated with a severe reduction in the localization of the centromere-associated protein CENP-F to kinetochores.