Interventions to reduce harm associated with adolescent substance use

A major proportion of the disease burden and deaths for young people in developed nations is attributable to misuse of alcohol and illicit drugs. Patterns of substance use established in adolescence are quite stable and predict chronic patterns of use, mortality, and morbidity later in life. We integrated findings of systematic reviews to summarise evidence for interventions aimed at prevention and reduction of harms related to adolescent substance use. Evidence of efficacy was available for developmental prevention interventions that aim to prevent onset of harmful patterns in settings such as vulnerable families, schools, and communities, and universal strategies to reduce attractiveness of substance use. Regulatory interventions aim to increase perceived costs and reduce availability and accessibility of substances. Increasing price, restricting settings of use, and raising legal purchase age are effective in reducing use of alcohol and tobacco and related harms. Screening and brief intervention are efficacious, but efficacy of a range of treatment approaches has not been reliably established. Harm-reduction interventions are effective in young people involved in risky and injecting substance use.

LARP1 post-transcriptionally regulates mTOR and contributes to cancer progression

RNA-binding proteins (RBPs) bind to and post-transcriptionally regulate the stability of mRNAs. La-related protein 1 (LARP1) is a conserved RBP that interacts with poly-A-binding protein and is known to regulate 5'-terminal oligopyrimidine tract (TOP) mRNA translation. Here, we show that LARP1 is complexed to 3000 mRNAs enriched for cancer pathways. A prominent member of the LARP1 interactome is mTOR whose mRNA transcript is stabilized by LARP1. At a functional level, we show that LARP1 promotes cell migration, invasion, anchorage-independent growth and in vivo tumorigenesis. Furthermore, we show that LARP1 expression is elevated in epithelial cancers such as cervical and non-small cell lung cancers, where its expression correlates with disease progression and adverse prognosis, respectively. We therefore conclude that, through the post-transcriptional regulation of genes such as mTOR within cancer pathways, LARP1 contributes to cancer progression.

A targeted deletion in the endocytic receptor gene Endo180 results in a defect in collagen uptake

The four members of the mannose receptor family (the mannose receptor, the M-type phospholipase A(2) receptor, DEC-205 and Endo180) share a common extracellular arrangement of an amino-terminal cysteine-rich domain followed by a fibronectin type II (FNII) domain and multiple C-type lectin-like domains (CTLDs). In addition, all have a short cytoplasmic domain, which mediates their constitutive recycling between the plasma membrane and the endosomal apparatus, suggesting that these receptors function to internalize ligands for intracellular delivery. We have generated mice with a targeted deletion of Endo180 exons 2-6 and show that this mutation results in the efficient expression of a truncated Endo180 protein that lacks the cysteine-rich domain, the FNII domain and CTLD1. Analysis of embryonic fibroblasts reveals that this mutation does not disrupt the C-type lectin activity that is mediated by CTLD2, but results in cells that have a defect in collagen binding and internalization and an impaired migratory phenotype.

The collagen receptor Endo180 (CD280) Is expressed on basal-like breast tumor cells and promotes tumor growth in vivo

Tumor cell invasion into the surrounding stroma requires increased cell motility and extensive remodeling of the extracellular matrix. Endo180 (CD280, MRC2, urokinase-type plasminogen activator receptor-associated protein) is a recycling endocytic receptor that functions in both these cellular activities by promoting cell migration and uptake of collagens for intracellular degradation. In the normal breast, Endo180 is predominantly expressed by stromal fibroblasts. The contrary observation that Endo180 is expressed on epithelial tumor cell lines that display a high invasive capacity suggested that up-regulation of this receptor may be an associated and functional component in the acquisition of a more aggressive phenotype by tumor cells in vivo. Here, we show that high levels of Endo180 are found in a subset of basal-like breast cancers and that this expression is an independent prognostic marker for shorter disease-free survival. Two potential mechanisms for Endo180 up-regulation were uncovered. First, it was shown that Endo180 can be transcriptionally up-regulated in vitro following transforming growth factor-beta treatment of breast cancer cells. Second, a proportion of Endo180(+) tumors were shown to have Endo180 gene copy number gains and amplifications. To investigate the functional consequence of Endo180 up-regulation, MCF7 cells transfected with Endo180 were inoculated into immunocompromised mice. Expression of wild-type Endo180, but not an internalization-defective Endo180 mutant, resulted in enhanced tumor growth together with a reduction in tumor collagen content. Together, these data argue that elevated expression of this receptor in tumor cells could have important consequences in subsets of basal-like carcinomas for which there is a current lack of effective treatment.

Endosomes generate localized Rho-ROCK-MLC2-based contractile signals via Endo180 to promote adhesion disassembly

The regulated assembly and disassembly of focal adhesions and adherens junctions contributes to cell motility and tumor invasion. Pivotal in this process is phosphorylation of myosin light chain-2 (MLC2) by Rho kinase (ROCK) downstream of Rho activation, which generates the contractile force necessary to drive disassembly of epithelial cell–cell junctions and cell–matrix adhesions at the rear of migrating cells. How Rho–ROCK–MLC2 activation occurs at these distinct cellular locations is not known, but the emerging concept that endocytic dynamics can coordinate key intracellular signaling events provides vital clues. We report that endosomes containing the promigratory receptor Endo180 (CD280) can generate Rho–ROCK–MLC2–based contractile signals. Moreover, we provide evidence for a cellular mechanism in which Endo180-containing endosomes are spatially localized to facilitate their contractile signals directly at sites of adhesion turnover. We propose migration driven by Endo180 as a model for the spatial regulation of contractility and adhesion dynamics by endosomes.

N-WASP activation by a β1-integrin-dependent mechanism supports PI3K-independent chemotaxis stimulated by urokinase-type plasminogen activator

Urokinase-type plasminogen activator (uPA)-uPA receptor (uPAR) and epidermal growth factor (EGF)-EGF receptor (EGFR) expression is highly correlated with breast cancer metastasis. Phosphoinositide 3-kinase (PI3K),small Rho GTPases, such as Cdc42 and Rac1, and neuronal Wiskott Aldrich syndrome protein (N-WASP) are key effectors that regulate dynamic changes in the actin cytoskeleton and cell migration. uPA- and EGF-stimulated chemotaxis,cytoskeletal rearrangements and activation of Cdc42, Rac1 and N-WASP were studied in the highly metastatic human breast cancer cell line MDA MB 231. These studies reveal that divergent signalling occurs downstream of PI3K. The activity of PI3K was not necessary for uPA-induced chemotactic responses, but those induced by EGF were entirely dependent upon PI3K. Furthermore,PI3K-independent chemotactic signalling by uPA was shown to involve disruption of an interaction between β1-integrins and N-WASP and translocation of N-WASP to the actin cytoskeleton.

GPI-anchored uPAR requires Endo180 for rapid directional sensing during chemotaxis

Urokinase-type plasminogen activator (uPA) and its receptor (uPAR) play an important role in cell guidance and chemotaxis during normal and pathological events. uPAR is GPI-anchored and the mechanism by which it transmits intracellular polarity cues across the plasma membrane during directional sensing has not been elucidated. The constitutively recycling endocytic receptor Endo180 forms a trimolecular complex with uPAR in the presence of uPA, hence its alternate name uPAR-associated protein. Here, we demonstrate that Endo180 is a general promoter of random cell migration and has a more specific function in cell chemotaxis up a uPA gradient. Endo180 expression was demonstrated to enhance uPA-mediated filopodia production and promote rapid activation of Cdc42 and Rac. Expression of a noninternalizing Endo180 mutant revealed that promotion of random cell migration requires receptor endocytosis, whereas the chemotactic response to uPA does not. From these studies, we conclude that Endo180 is a crucial link between uPA-uPAR and setting of the internal cellular compass.

Regulation by fibrinogen and its products of intercellular adhesion molecule-1 expression in human saphenous vein endothelial cells

It has been reported that fibrinogen may act as a bridging ligand, binding to intercellular adhesion molecule-1 (ICAM-1) on human umbilical vein endothelial cells and to Mac-1 on THP-1 cells (a monocytic cell line) to increase adhesion. In this study, we investigated whether fibrinogen altered the expression of ICAM-1 and, thus, increased the adhesion of THP-1 cells to cultured human saphenous vein endothelial cells (HSVECs). Incubation of HSVECs with 0.3 to 4 micromol/L fibrinogen caused a time- and concentration-dependent increase in ICAM-1, as determined by ELISA. The 4- to 5-fold increase in ICAM-1 protein concentration in HSVECs stimulated by 4 micromol/L fibrinogen for 6 hours was concomitant with a 4- to 5-fold increase in ICAM-1 mRNA. This fibrinogen-stimulated ICAM-1 upregulation was associated with a 2-fold increase in THP-1 cell adhesion to HSVECs. The fibrinogen-derived peptide Bbeta15-42 bound to HSVECs (K(d) 0.18 micromol/L). Preincubation of HSVECs with Bbeta15-42, a neutralizing antibody to urokinase plasminogen activator (uPA), or the F(ab)(1) fragment of a monoclonal antibody to vascular endothelial cadherin significantly attenuated the increase in ICAM-1 stimulated by fibrinogen. Capillary electrophoretic analysis indicated that anti-uPA prevented the release of any fibrinopeptide B (Bbeta1-14) in cultures of HSVECs incubated with 4 micromol/L fibrinogen for 6 hours. Moreover, incubation of HSVECs with either fibrin monomer (1 micromol/L) or monoclonal antibodies to vascular endothelial cadherin (25 microg/mL) increased ICAM-1 protein concentration 3- to 4-fold. These findings indicate that cleavage of fibrinopeptide B from fibrinogen by endothelial uPA permits the exposed Bbeta15-42 sequence of fibrinogen to bind to vascular endothelial cadherin on HSVECs and to upregulate the expression of ICAM-1.

Circulating sphingosine-1-phosphate and erythrocyte sphingosine kinase-1 activity as novel biomarkers for early prostate cancer detection

BACKGROUND

Current markers available for screening normal populations and for monitoring prostate cancer (PCa) treatment lack sensitivity and selectivity. Sphingosine-1-phosphate (S1P) is a circulating lipid second messenger involved in cell growth and migration, the immune response, angiogenesis, and malignant transformation.

METHODS

Eighty-eight patients with localised, locally advanced, or metastatic PCa were recruited into this prospective single-centre study. Plasma S1P levels were measured and compared with age-matched controls with benign prostate hyperplasia (BPH) (n=110) or with young healthy males with the very small chance of having PCa foci (n=20).

RESULTS

Levels of circulating S1P were significantly higher in healthy subjects (10.36 ± 0.69 pmol per mg protein, P<0.0001) and patients with BPH (9.39 ± 0.75, P=0.0013) than in patients with PCa (6.89 ± 0.58, ANOVA, P=0.0019). Circulating S1P levels were an early marker of PCa progression to hormonal unresponsiveness and correlated with prostate-specific antigen (PSA) levels and lymph node metastasis. During the course of the study, nine patients have died of PCa. Importantly, their circulating S1P levels were significantly lower (5.11 ± 0.75) than in the surviving patients (7.02 ± 0.22, n=79, P=0.0439). Our data suggest that the decrease in circulating S1P during PCa progression may stem from a highly significant downregulation of erythrocyte sphingosine kinase-1 (SphK1) activity (2.14 ± 0.17 pmol per mg protein per minute in PCa patients vs 4.7 ± 0.42 in healthy individuals, P<0.0001), which may be a potential mechanism of cancer-induced anaemia.

CONCLUSION

This current study has provided a potential mechanism for cancer-related anaemia and the first evidence that plasma S1P and erythrocyte SphK1 activity are the potential markers for the diagnosis, monitoring, and predicating for PCa mortality.

AGE-modified basement membrane cooperates with Endo180 to promote epithelial cell invasiveness and decrease prostate cancer survival

Biomechanical strain imposed by age-related thickening of the basal lamina and augmented tissue stiffness in the prostate gland coincides with increased cancer risk. Here we hypothesized that the structural alterations in the basal lamina associated with age can induce mechanotransduction pathways in prostate epithelial cells (PECs) to promote invasiveness and cancer progression. To demonstrate this, we developed a 3D model of PEC acini in which thickening and stiffening of basal lamina matrix was induced by advanced glycation end-product (AGE)-dependent non-enzymatic crosslinking of its major components, collagen IV and laminin. We used this model to demonstrate that antibody targeted blockade of CTLD2, the second of eight C-type lectin-like domains in Endo180 (CD280, CLEC13E, KIAA0709, MRC2, TEM9, uPARAP) that can recognize glycosylated collagens, reversed actinomyosin-based contractility [myosin-light chain-2 (MLC2) phosphorylation], loss of cell polarity, loss of cell-cell junctions, luminal infiltration and basal invasion induced by AGE-modified basal lamina matrix in PEC acini. Our in vitro results were concordant with luminal occlusion of acini in the prostate glands of adult Endo180(Δ) (Ex2-6/) (Δ) (Ex2-6) mice, with constitutively exposed CTLD2 and decreased survival of men with early (non-invasive) prostate cancer with high epithelial Endo180 expression and levels of AGE. These findings indicate that AGE-dependent modification of the basal lamina induces invasive behaviour in non-transformed PECs via a molecular mechanism linked to cancer progression. This study provides a rationale for targeting CTLD2 in Endo180 in prostate cancer and other pathologies in which increased basal lamina thickness and tissue stiffness are driving factors. © 2014 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

Mannose receptor regulation of macrophage cell migration

The migration of macrophages through peripheral tissues is an essential step in the host response to infection, inflammation, and ischemia as well as in tumor progression and tissue repair. The mannose receptor (MR; CD206, previously known as the macrophage MR) is a 175-kDa type I transmembrane glycoprotein and is a member of a family of four recycling endocytic receptors, which share a common extracellular domain structure but distinct ligand-binding properties and cell type expression patterns. MR has been shown to bind and internalize carbohydrate and collagen ligands and more recently, to have a role in myoblast motility and muscle growth. Given that the related Endo180 (CD280) receptor has also been shown to have a promigratory role, we hypothesized that MR may be involved in regulating macrophage migration and/or chemotaxis. Contrary to expectation, bone marrow-derived macrophages (BMM) from MR-deficient mice showed an increase in random cell migration and no impairment in chemotactic response to a gradient of CSF-1. To investigate whether the related promigratory Endo180 receptor might compensate for lack of MR, mice with homozygous deletions in MR and Endo180 were generated. These animals showed no obvious phenotypic abnormality, and their BMM, like those from MR-deficient mice, retained an enhanced migratory behavior. As MR is down-regulated during macrophage activation, these findings have implications for the regulation of macrophage migration during different stages of pathogenesis.

Endo180 expression with cofunctional partners MT1-MMP and uPAR-uPA is correlated with prostate cancer progression

Endo180 (CD280; MRC2; uPARAP) regulates collagen remodelling and chemotactic cell migration through cooperation with membrane type-1 matrix metalloproteinase (MT1-MMP), urokinase-type plasminogen activator receptor (uPAR) and urokinase-type plasminogen activator (uPA). One hundred and sixty nine prostate tissue sections clinically graded as benign prostatic hyperplasia (BPH) (n=29) or prostate cancer (PCA) with Gleason scores indicating low (< or =7(3+4); n=26), intermediate (7(4+3)-8; n=96) or high (9-10; n=19) clinical risk were immunofluorescently stained for Endo180, pan-cytokeratin (pCk), vimentin, MT1-MMP and uPAR-uPA. Quantification of % Endo180(+)/pCk(-) and Endo180(+)/pCk(+) cells in entire tissue cores revealed stromal (p=0.0001) and epithelial (p=0.0001) upregulation of Endo180 in PCA compared to BPH. Epithelial Endo180 expression was significantly different between the three clinical risk groups of PCA (p<0.05). Correlations with MT1-MMP and uPAR-uPA confirmed the functionality of Endo180 during PCA progression. This molecular evaluation is the first step in the exploration of Endo180 in PCA diagnosis and therapy.

A 18F radiolabelled Zn(ii) sensing fluorescent probe

A selective fluorescent probe for Zn(ii), AQA-F, has been synthesized. AQA-F exhibits a ratiometric shift in emission of up to 80 nm upon binding Zn(ii) ([AQA-F] = 0.1 mM, [Zn(ii)Cl2] = 0-300 μM). An enhancement of quantum yield from Φ = 4.2% to Φ = 35% is also observed. AQA-F has a binding constant, Kd = 15.2 μM with Zn(ii). This probe has been shown to respond to endogenous Zn(ii) levels in vitro in prostate and prostate cancer cell lines. [18F]AQA-F has been synthesized with a radiochemical yield of 8.6% and a radiochemical purity of 97% in 88 minutes. AQA-F shows the potential for a dual modal PET/fluorescence imaging probe for Zn(ii).

Survival Outcome and EMT Suppression Mediated by a Lectin Domain Interaction of Endo180 and CD147

Epithelial cell-cell contacts maintain normal glandular tissue homeostasis, and their breakage can trigger epithelial-to-mesenchymal transition (EMT), a fundamental step in the development of metastatic cancer. Despite the ability of C-type lectin domains (CTLD) to modulate cell-cell adhesion, it is not known if they modulate epithelial adhesion in EMT and tumor progression. Here, the multi-CTLD mannose receptor, Endo180 (MRC2/uPARAP), was shown using the Kaplan-Meier analysis to be predictive of survival outcome in men with early prostate cancer. A proteomic screen of novel interaction partners with the fourth CTLD (CTLD4) in Endo180 revealed that its complex with CD147 is indispensable for the stability of three-dimensional acini formed by nontransformed prostate epithelial cells (PEC). Mechanistic study using knockdown of Endo180 or CD147, and treatment with an Endo180 mAb targeting CTLD4 (clone 39.10), or a dominant-negative GST-CTLD4 chimeric protein, induced scattering of PECs associated with internalization of Endo180 into endosomes, loss of E-cadherin (CDH1/ECAD), and unzipping of cell-cell junctions. These findings are the first to demonstrate that a CTLD acts as a suppressor and regulatory switch for EMT; thus, positing that stabilization of Endo180-CD147 complex is a viable therapeutic strategy to improve rates of prostate cancer survival.

IMPLICATIONS

This study identifies the interaction between CTLD4 in Endo180 and CD147 as an EMT suppressor and indicates that stabilization of this molecular complex improves prostate cancer survival rates.

TGFβ1-Endo180-dependent collagen deposition is dysregulated at the tumour-stromal interface in bone metastasis

Cellular niches in adult tissue can harbour dysregulated microenvironments that become the driving force behind disease progression. The major environmental change when metastatic cells arrive in the bone is the destruction of mineralized type I collagen matrix. Once metastatic niches establish in bone, the invading tumour cells initiate a vicious cycle of osteolytic lesion formation via the dysregulation of paracrine signals and uncoupling of normal bone resorption and production. Here we report that the collagen receptor Endo180 (CD280, MRC2, uPARAP) participates in collagen deposition by primary human osteoblasts during de novo osteoid formation. This newly recognized function of Endo180 was suppressed in osteoblasts following heterotypic direct cell-cell contact in co-culture with prostate tumour cells. Reciprocal Endo180 up-regulation in osteolytic prostate tumour cells (PC3 and DU145) followed their direct contact with osteoblasts and promoted de novo collagen internalization, which is a previously characterized function of the constitutively recycling Endo180 receptor. The osteoblastic suppression and tumour cell-associated enhancement of Endo180 expression were equally sustained in these direct co-cultures. These findings are the first to demonstrate that increased tumour cell participation in collagen degradation and decreased collagen formation by osteoblasts in the osteolytic microenvironment are linked to the divergent regulation of a collagen-binding receptor. Immunohistochemical analysis of core biopsies from bone metastasis revealed higher levels of Endo180 expression in tumour cell foci than cells in the surrounding stroma. Additional experiments in prostate cell-osteoblast co-cultures indicate that divergent regulation of Endo180 is the result of dysregulated TGFβ1 signalling. The findings of this study provide a rationale for targeting collagen remodelling by Endo180 in bone metastases and other collagen matrix pathologies.

Evaluation of blood collected on filter paper for detection of antibodies to human immunodeficiency virus type 1

This study was undertaken to evaluate the sensitivity and specificity of a commercial enzyme immunoassay in detecting antibody to human immunodeficiency virus type 1 using whole-blood specimens collected onto filter paper. Results obtained with specimens collected onto filter paper were comparable with those obtained with the corresponding serum or plasma specimens.

Fluorescence-based experimental model to evaluate the concomitant effect of drugs on the tumour microenvironment and cancer cells

The response of the tumour microenvironment to anti-cancer drugs can influence treatment efficacy. Current drug-screening methodologies fail to distinguish and quantify simultaneously the concomitant effect of drugs on the tumour stroma and cancer cells. To overcome this limitation we have developed a fluorescence-based experimental model that employs mCherry-labelled stromal cells (e.g. bone marrow fibroblastic stromal cells) co-cultured in direct contact with enhanced green fluorescent protein-labelled tumour cell lines for accurate assessment of proliferation and viability in both cell compartments and adhesion of tumour cells. Additionally, we used fluorescence-based image analysis to determine morphological changes that correlate with cell function (e.g. morphology of the actin cytoskeleton and nuclearity of osteoclasts to predict their bone resorption activity). Using this platform we have revealed that dexamethasone induces HS5 fibroblast proliferation and contact with multiple myeloma cells via a process involving Src/c-Abl kinases. Osteoclasts also inhibited dexamethasone-induced apoptosis in myeloma cells while retaining their normal morphology and functionality in bone resorption. Myeloma resistance to dexamethasone mediated by HS5 cells and osteoclasts was reversed by treatment with the Src/c-Abl inhibitor dasatinib but not with bortezomib. This new experimental platform provides a more precise screening of new therapeutics for improved efficacy of tumour cell killing within the bone marrow microenvironment.

Fibrin monomer and fibrinopeptide B act additively to increase DNA synthesis in smooth muscle cells cultured from human saphenous vein

PURPOSE

We investigated the hypothesis that fibrinogen increased DNA synthesis (and cell proliferation) of smooth muscle cells (SMCs) cultured from human saphenous vein and that the increased DNA synthesis was attenuated when cells were cultured on polymeric collagen.

METHODS

SMCs were cultured from human saphenous vein on plastic, fibronectin, monomeric, and polymeric collagen. Fibrinogen products were prepared by proteolytic digestion. DNA synthesis was measured by bromodeoxyuridine incorporation into DNA, cell proliferation by cell counting, cyclic adenosine monophosphate by enzyme-linked immunosorbent assay, and fibrinopeptide B labeled with iodine 125 used for binding studies.

RESULTS

Fibrin monomer (0.003-0.1 micromol/L) stimulated a concentration-dependent increase in DNA synthesis of up to 10-fold, which could be inhibited by the peptide Bbeta15-42. The stimulation of DNA synthesis was highest for cells cultured on plastic and lowest for cells cultured on type I collagen polymer. Much higher concentrations of fibrinogen (0.3-1 micromol/L) were required to effect similar increases in DNA synthesis. Fibrinogen had a particular effect to augment DNA synthesis, up to 14-fold, when cells were cultured on monomeric type I collagen. This augmented DNA synthesis was inhibited by a neutralizing antibody to urokinase-type plasminogen activator. Incubation of cells cultured on collagen monomer with fibrinogen resulted in production of fibrinopeptide B. Fibrinopeptide B (5 micromol/L) increased DNA synthesis by fourfold and had additive effects with fibrin monomer to increase DNA synthesis. Iodinated tyrosine fibrinopeptide B bound to SMCs (dissociation constant 0.6 micromol/L).

CONCLUSION

Cultured human saphenous vein SMCs appear to have high-affinity receptors for fibrin monomer and fibrinopeptide B, the engagement of which stimulates DNA synthesis. These mechanisms may be pertinent to the association between fibrinogen and vein graft stenosis in vivo.

Endo180 at the cutting edge of bone cancer treatment and beyond

Skeletal bone is an attractive site for secondary tumour growth and is also home to spontaneous primary cancer. Treatment of bone metastasis is focused on limiting the vicious cycle of bone destruction with bisphosphonates or inhibition of receptor activator of nuclear factor‐κB ligand (RANKL) with the fully human monoclonal antibody denosumab. The estimated 1 million deaths/year where bone metastasis is present, and the high healthcare costs required for its management, have ignited intensive research into the cellular and molecular pathology of osteolysis, involving interplay between tumour cells, bone‐forming osteoblasts and bone‐degrading osteoclasts. Compared to bone metastasis, knowledge about the pathology of primary bone cancers is limited. In recent work published in this journal, Engelholm et al provide a unique insight into how this poorly understood disease manifests and destroys bone. For the first time they have demonstrated that a mouse monoclonal antibody targeting the collagen receptor Endo180 (CD280, MRC2 uPARAP) can prevent osteolysis and bone destruction in a syngeneic model of advanced osteosarcoma. Their convincing findings make an important contribution towards Endo180‐based therapy being developed as an option for the treatment of bone cancer amongst other malignancies. © 2015 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

Confirmation of Legionella pneumophila cultures with a fluorescein-labeled monoclonal antibody

We compared a fluorescein-labeled monoclonal antibody directed against an outer membrane protein of Legionella pneumophila (Genetic Systems Corp. [GSC], Seattle, Wash.) with a similarly labeled polyclonal reagent (L. pneumophila serogroups 1 to 6, poly; BioDx, Inc., Denville, N.J.) for the confirmation of L. pneumophila isolates grown in culture. Duplicate suspensions of 52 organisms, including 21 L. pneumophila and 8 non-L. pneumophila species of legionella, were placed on individual glass slides, fixed, and stained with both reagents, and the results were compared. Both antisera correctly identified all L. pneumophila serogroups 1 to 6, but only the GSC reagent produced definitive staining of the L. pneumophila isolates of serogroups 7, 8, and 9. Additionally, the GSC reagent produced more uniform staining patterns around the legionella bacilli and displayed little background fluorescence when compared with the BioDx reagent.

How to Study Basement Membrane Stiffness as a Biophysical Trigger in Prostate Cancer and Other Age-related Pathologies or Metabolic Diseases

Here we describe a protocol that can be used to study the biophysical microenvironment related to increased thickness and stiffness of the basement membrane (BM) during age-related pathologies and metabolic disorders (e.g. cancer, diabetes, microvascular disease, retinopathy, nephropathy and neuropathy). The premise of the model is non-enzymatic crosslinking of reconstituted BM (rBM) matrix by treatment with glycolaldehyde (GLA) to promote advanced glycation endproduct (AGE) generation via the Maillard reaction. Examples of laboratory techniques that can be used to confirm AGE generation, non-enzymatic crosslinking and increased stiffness in GLA treated rBM are outlined. These include preparation of native rBM (treated with phosphate-buffered saline, PBS) and stiff rBM (treated with GLA) for determination of: its AGE content by photometric analysis and immunofluorescent microscopy, its non-enzymatic crosslinking by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS PAGE) as well as confocal microscopy, and its increased stiffness using rheometry. The procedure described here can be used to increase the rigidity (elastic moduli, E) of rBM up to 3.2-fold, consistent with measurements made in healthy versus diseased human prostate tissue. To recreate the biophysical microenvironment associated with the aging and diseased prostate gland three prostate cell types were introduced on to native rBM and stiff rBM: RWPE-1, prostate epithelial cells (PECs) derived from a normal prostate gland; BPH-1, PECs derived from a prostate gland affected by benign prostatic hyperplasia (BPH); and PC3, metastatic cells derived from a secondary bone tumor originating from prostate cancer. Multiple parameters can be measured, including the size, shape and invasive characteristics of the 3D glandular acini formed by RWPE-1 and BPH-1 on native versus stiff rBM, and average cell length, migratory velocity and persistence of cell movement of 3D spheroids formed by PC3 cells under the same conditions. Cell signaling pathways and the subcellular localization of proteins can also be assessed.

The toxic effect of cytostatics on primary cilia frequency and multiciliation

The primary cilium is considered as a key component of morphological cellular stability. However, cancer cells are notorious for lacking primary cilia in most cases, depending upon the tumour type. Previous reports have shown the effect of starvation and cytostatics on ciliogenesis in normal and cancer cells although with limited success, especially when concerning the latter. In this study, we evaluated the presence and frequency of primary cilia in breast fibroblasts and in triple-negative breast cancer cells after treatment with cytostatics finding that, in the case of breast fibroblasts, primary cilia were detected at their highest incidence 72 hours after treatment with 120 nM doxorubicin. Further, multiciliated cells were also detected after treatment with 80 nM doxorubicin. On the other hand, treatment with taxol increased the number of ciliated cells only at low concentrations (1.25 and 3.25 nM) and did not induce multiciliation. Interestingly, triple-negative breast cancer cells did not present primary cilia after treatment with either doxorubicin or taxol. This is the first study reporting the presence of multiple primary cilia in breast fibroblasts induced by doxorubicin. However, the null effect of these cytostatics on primary cilia incidence in the evaluated triple negative breast carcinomas cell lines requires further research.

Regulation of breast cancer cell chemotaxis by the phosphoinositide 3-kinase p110delta

Class IA phosphoinositide 3'-kinases (PI3Ks) regulate many cellular processes downstream of tyrosine kinases and Ras. Despite a clear implication of PI3K in cancer, little is known about the distribution of the different PI3K isoforms in malignant cells. We screened a large panel of tissues and cell lines for expression of class IA PI3Ks, and document a ubiquitous expression of the p110alpha and p110beta isoforms but a variable and more restricted tissue distribution of the p110delta isoform. Originally found in WBCs, p110delta was also detected in some nonhematopoietic cell types especially those of breast or melanocytic origin, both in the untransformed and transformed state. Isoform-specific neutralization of PI3K isoforms in breast cancer cell lines (by PI3K antibody microinjection or a p110delta-selective pharmacological inhibitor) demonstrated that p110delta is the most important class IA PI3K in the regulation of epidermal growth factor-driven motility in vitro, controlling the directionality and, to a lesser extent, the speed of migration. In contrast, p110beta was required for the direction but not the speed of migration, whereas p110alpha did not impact on either of these parameters. These results show a nonredundant function of PI3K isoforms downstream of the epidermal growth factor receptor and indicate that the presence of p110delta may confer breast cancer cells with selective migratory capacities. The potential clinical implications of p110delta expression in non-WBC-derived tumors are discussed.