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Ovarian cancer has a distinct tendency for metastasising via shedding of cancerous cells into the peritoneal cavity and implanting onto the peritoneum that lines the pelvic organs. Once ovarian cancer cells adhere to the peritoneal cells, they migrate through the peritoneal layer and invade the local organs. Alterations in the extracellular environment are critical for tumour initiation, progression and intra-peritoneal dissemination. To increase our understanding of the molecular mechanisms involved in ovarian cancer metastasis and to identify novel therapeutic targets, we recently studied the interaction of ovarian cancer and peritoneal cells using a proteomic approach. We identified several extracellular matrix (ECM) proteins including, fibronectin, TGFBI, periostin, annexin A2 and PAI-1 that were processed as a result of the ovarian cancer– peritoneal cell interaction. This review focuses on the functional role of these proteins in ovarian cancer metastasis. Our findings together with published literature support the notion that ECM processing via the plasminogen–plasmin pathway promotes the colonisation and attachment of ovarian cancer cells to the peritoneum and actively contributes to the early steps of ovarian cancer metastasis. [ABSTRACT FROM AUTHOR]

Normal reproductive function and fertility is considered a "sixth vital sign" because disruptions to this sensitive physiological system can forewarn other health issues, including exposure to environmental toxicants. We found that female mice exhibited profound loss of embryos during pre-implantation and fetal development coincident with a change to the source of their drinking water. When female mice were provided with tap water from the building in which they were housed (Water 2), instead of tap water from a neighboring building which was their previous supply (Water 1), ovulated oocytes were degenerated or had impaired meiotic maturation, and failed to form embryos. The harmful effects of Water 2 exposure were not reversible even following a recovery period; however, carbon-filtration of Water 2 removed the toxic contaminant. Water composition analysis to identify the responsible toxicant(s) found that trace elements were present at expected levels and phthalates were undetectable. Per- and Poly-fluoroalkyl Substances (PFAS), a family of persistent organic pollutants were detected at ∼4 ng/L. To investigate further, female mice were given drinking water categorized by level of PFAS contamination (0.6 ng/L, 2.8 ng/L, or 4.4 ng/L) for 9 weeks. Compared to mice consuming purified MilliQ water, mice consuming PFAS-contaminated water had decreased oocyte quality, impaired embryogenesis and reduced cell numbers in blastocysts. PFAS concentration in the drinking water was negatively correlated with oocyte viability. Importantly, the levels of PFAS detected in the tap water are within current "safe level" guidelines, and further research is needed to determine whether PFAS are responsible for the observed reproductive toxicity. However, this research demonstrating that water deemed suitable for human consumption has detrimental effects on mammalian embryo development has important implications for public health and water quality policies., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The handling editor AW declared a past co-authorship with the author SR., (© 2024 Winstanley, Gonzalez, Andreas, Connaughton, Bergen, Ween, Russell, Shearer, Robertson and Robker.)

Cigarette smoke (CS)-induced emphysema is an important contributor to chronic obstructive pulmonary disease (COPD). We have shown the efficacy of azithromycin in reducing airway inflammation in COPD and in reducing exacerbations in severe asthma; however, the effects of long-term azithromycin on emphysema development have not been shown. We employed live animal imaging to monitor emphysema-like development and the effects of interventional azithromycin treatment in CS-exposed mice. BALB/c mice (female, 10 weeks; n = 10) were exposed to CS for 1 hr twice daily, 5 days/week, and for 12 weeks (CS). Half were cotreated with low-dose azithromycin during weeks 7-12 (CS + Azi; 0.2 mg kg -1  day -1 ). Microcomputed tomography (CT) and magnetic resonance imaging (MRI) scans were acquired longitudinally. Histological examinations were performed post mortem (mean linear intercept (Lm) and leukocyte infiltration). CS increased median Lm (CS: 42.45 µm versus control: 34.7 µm; p = .0317), this was recovered in CS + Azi mice (33.03 µm). Average CT values were reduced in CS mice (CS: -399.5 Hounsfield units (HU) versus control: -384.9 HU; p = .0286) but not in CS + Azi mice (-377.3 HU). CT values negatively correlated with Lm (r = -.7972; p = .0029) and T 2 -weighted MRI (r = -.6434; p = .0278). MRI also showed significant CS-induced inflammatory changes that were attenuated by azithromycin in the lungs, and positively correlated with Lm (r = .7622; p = .0055) and inflammatory foci counts (r = .6503; p = .0257). Monitoring of emphysema development is possible via micro-CT and MRI. Interventional azithromycin treatment in CS-exposed mice attenuated the development of pulmonary emphysema-like changes., (© 2020 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.)

Bushfires are increasing in frequency and severity worldwide. Bushfire smoke contains organic/inorganic compounds including aldehydes and acrolein. We described suppressive effects of tobacco smoke on the phagocytic capacity of airway macrophages, linked to secondary necrosis of uncleared apoptotic epithelial cells, persistence of non-typeable H. influenzae (NTHi), and inflammation. We hypothesised that bushfire smoke extract (BFSE) would similarly impair macrophage function. THP-1 or monocyte-derived macrophages (MDM) were exposed to 1-10% BFSE prepared from foliage of 5 common Australian native plants (genus Acacia or Eucalyptus), or 10% cigarette smoke extract (CSE). Phagocytic recognition receptors were measured by flow cytometry; pro-inflammatory cytokines and caspase 1 by immunofluorescence or cytometric bead array; viability by LDH assay; and capsase-3/PARP by western blot. BFSE significantly decreased phagocytosis of apoptotic cells or NTHi by both THP-1 macrophages and MDM vs air control, consistent with the effects of CSE. BFSE significantly decreased MDM expression of CD36, CD44, SR-A1, CD206 and TLR-2 and increased active IL-1β, caspase-1 and secreted IL-8. BFSE dose-dependently decreased THP-1 macrophage viability (5-fold increase in LDH at 10%) and significantly increased active caspase-3. BFSE impairs macrophage function to a similar extent as CSE, highlighting the need for further research, especially in patients with pre-existing lung disease.

Introduction: We have previously established a link between impaired phagocytic capacity and deregulated S1P signaling in alveolar macrophages from COPD subjects. We hypothesize that this defect may include a disruption of epithelial-macrophage crosstalk via Spns2-mediated intercellular S1P signaling., Methods: Primary alveolar macrophages and bronchial epithelial cells from COPD subjects and controls, cell lines, and a mouse model of chronic cigarette smoke exposure were studied. Cells were exposed to 10% cigarette smoke extract, or vehicle control. Spns2 expression and subcellular localization was studied by immunofluorescence, confocal microscopy and RT-PCR. Phagocytosis was assessed by flow-cytometry. Levels of intra- and extracellular S1P were measured by S1P [3H]-labeling., Results: Spns2 expression was significantly increased (p<0.05) in alveolar macrophages from current-smokers/COPD patients (n = 5) compared to healthy nonsmokers (n = 8) and non-smoker lung transplant patients (n = 4). Consistent with this finding, cigarette smoke induced a significant increase in Spns2 expression in both human alveolar and THP-1 macrophages. In contrast, a remarkable Spns2 down-regulation was noted in response to cigarette smoke in 16HBE14o- cell line (p<0.001 in 3 experiments), primary nasal epithelial cells (p<0.01 in 2 experiments), and in smoke-exposed mice (p<0.001, n = 6 animals per group). Spns2 was localized to cilia in primary bronchial epithelial cells. In both macrophage and epithelial cell types, Spns2 was also found localized to cytoplasm and the nucleus, in line with a predicted bipartile Nuclear Localization Signal at the position aa282 of the human Spns2 sequence. In smoke-exposed mice, alveolar macrophage phagocytic function positively correlated with Spns2 protein expression in bronchial epithelial cells., Conclusion: Our data suggest that the epithelium may be the major source for extracellular S1P in the airway and that there is a possible disruption of epithelial/macrophage cross talk via Spns2-mediated S1P signaling in COPD and in response to cigarette smoke exposure.

We reported defective efferocytosis associated with cigarette smoking and/or airway inflammation in chronic lung diseases, including chronic obstructive pulmonary disease, severe asthma, and childhood bronchiectasis. We also showed defects in phagocytosis of nontypeable Haemophilus influenzae (NTHi), a common colonizer of the lower airway in these diseases. These defects could be substantially overcome with low-dose azithromycin; however, chronic use may induce bacterial resistance. The aim of the present study was therefore to investigate two novel macrolides-2'-desoxy-9-(S)-erythromycylamine (GS-459755) and azithromycin-based 2'-desoxy molecule (GS-560660)-with significantly diminished antibiotic activity against Staphylococcus aureus , Streptococcus pneumonia , Moraxella catarrhalis , and H. influenzae We tested their effects on efferocytosis, phagocytosis of NTHi, cell viability, receptors involved in recognition of apoptotic cells and/or NTHi (flow cytometry), secreted and cleaved intracellular IL-1β (cytometric bead array, immunofluorescence/confocal microscopy), and nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3) using primary alveolar macrophages and THP-1 macrophages ± 10% cigarette smoke extract. Dose-response experiments showed optimal prophagocytic effects of GS-459755 and GS-560660 at concentrations of 0.5-1 µg/ml compared with our findings with azithromycin. Both macrolides significantly improved phagocytosis of apoptotic cells and NTHi (e.g., increases in efferocytosis and phagocytosis of NTHi: GS-459755, 23 and 22.5%, P = 0.043; GS-560660, 23.5 and 22%, P = 0.043, respectively). Macrophage viability remained >85% following 24 h exposure to either macrolide at concentrations up to 20 µg/ml. Secreted and intracellular-cleaved IL-1β was decreased with both macrolides with no significant changes in recognition molecules c-mer proto-oncogene tyrosine kinase; scavenger receptor class A, member 1; Toll-like receptor 2/4; or CD36. Particulate cytoplasmic immunofluorescence of NLRP3 inflammasome was also reduced significantly. We conclude that GS-459755 and GS-560660 may be useful for reducing airway inflammation in chronic lung diseases without inducing bacterial resistance., (Copyright © 2017 the American Physiological Society.)

Alveolar macrophages from chronic obstructive pulmonary disease patients and cigarette smokers are deficient in their ability to phagocytose apoptotic bronchial epithelial cells (efferocytosis). We hypothesized that the defect is mediated via inhibition of sphingosine kinases and/or their subcellular mislocalization in response to cigarette smoke and can be normalized with exogenous sphingosine-1-phosphate or FTY720 (fingolimod), a modulator of sphingosine-1-phosphate signaling, which has been shown to be clinically useful in multiple sclerosis. Measurement of sphingosine kinase 1/2 activities by [(32)P]-labeled sphingosine-1-phosphate revealed a 30% reduction of sphingosine kinase 1 (P < 0.05) and a nonsignificant decrease of sphingosine kinase 2 in THP-1 macrophages after 1 h cigarette smoke extract exposure. By confocal analysis macrophage sphingosine kinase 1 protein was normally localized to the plasma membrane and cytoplasm and sphingosine kinase 2 to the nucleus and cytoplasm but absent at the cell surface. Cigarette smoke extract exposure (24 h) led to a retraction of sphingosine kinase 1 from the plasma membrane and sphingosine kinase 1/2 clumping in the Golgi domain. Selective inhibition of sphingosine kinase 2 with 25 µM ABC294640 led to 36% inhibition of efferocytosis (P < 0.05); 10 µM sphingosine kinase inhibitor/5C (sphingosine kinase 1-selective inhibitor) induced a nonsignificant inhibition of efferocytosis, but its combination with ABC294640 led to 56% inhibition (P < 0.01 vs. control and < 0.05 vs. single inhibitors). Cigarette smoke-inhibited efferocytosis was significantly (P < 0.05) reversed to near-control levels in the presence of 10-100 nM exogenous sphingosine-1-phosphate or FTY720, and FTY720 reduced cigarette smoke-induced clumping of sphingosine kinase 1/2 in the Golgi domain. These data strongly support a role of sphingosine kinase 1/2 in efferocytosis and as novel therapeutic targets in chronic obstructive pulmonary disease., (© Society for Leukocyte Biology.)

Unlabelled: A defective ability of alveolar macrophages to phagocytose both apoptotic airway epithelial cells and bacteria in chronic lung diseases potentially associated with inflammation and bacterial colonisation of the lower airways, often with non-typeable Haemophilus influenzae (NTHi), has been shown. We routinely assess phagocytosis in the airway of children: however, the small volume of BAL obtained usually precludes the investigation of phagocytosis of both (potentially equally relevant) apoptotic cells and NTHi., Methods: We established a 'one-tube, dual target' flow-cytometric assay for investigating alveolar macrophage phagocytosis of both apoptotic cells and NTHi. The effect of bacterial presence on phagocytosis of apoptotic cells was assessed by comparing results using this technique to standard 'two tube, single target' methods. The comparative ability of alveolar macrophages to phagocytose NTHi or apoptotic cells was assessed in 10/group of healthy adult controls and patients with COPD, 12 children with bronchiectasis, and 10 children controls. We then assessed the influence of increasing concentrations of NTHi targets on the ability of THP-1 macrophages to simultaneously phagocytose apoptotic cells., Results: Alveolar macrophages phagocytosed NTHi more avidly than apoptotic cells (mean ± SEM: apoptotic cells 15.4% ± 0.5 vs. NTHi 17.2% ± 0.7, p<0.05). The presence of NTHi targets (ratio of 1:100 macrophage: NTHi; 2 × 1 0(7) CFU routinely applied in our assay) had no effect on the ability of macrophages to simultaneously phagocytose apoptotic cells. However, when bacterial numbers were increased (up to 4-fold) there was a small but significant suppressive effect on the ability of macrophages to phagocytose apoptotic cells., Conclusions: We describe a small volume 'one tube, dual target' technique to measure phagocytosis of apoptotic cells and NTHi. We show that alveolar macrophages phagocytose NTHi more avidly than apoptotic cells, and that an increased presence of NTHi in the airway may reduce the ability of alveolar macrophages to phagocytose apoptotic cells., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Over 80% of ovarian cancer patients develop chemoresistance which results in a lethal course of the disease. A well-established cause of chemoresistance involves the family of ATP-binding cassette transporters, or ABC transporters that transport a wide range of substrates including metabolic products, nutrients, lipids, and drugs across extra- and intra-cellular membranes. Expressions of various ABC transporters, shown to reduce the intracellular accumulation of chemotherapy drugs, are increased following chemotherapy and impact on ovarian cancer survival. Although clinical trials to date using ABC transporter inhibitors have been disappointing, ABC transporter inhibition remains an attractive potential adjuvant to chemotherapy. A greater understanding of their physiological functions and role in ovarian cancer chemoresistance will be important for the development of more effective targeted therapies. This article will review the role of the ABC transporter family in ovarian cancer progression and chemoresistance as well as the clinical attempts used to date to reverse chemoresistance., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)