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Background: Pancreatic Cancer (PC) is one of the most aggressive cancer types, with less than 10% of patients surviving at 5-years. One hallmark of PC is the frequent mutation of the oncogene KRAS resulting in the constitutive activation of the phosphoinositide-3-kinase (PI3K) signaling pathway. The PI3K pathway is an intracellular signaling pathway that regulates cell growth, metabolism, and survival in response to extracellular signals. Given the importance of deregulated phosphoinositide (PI) signaling in PC, we hypothesize that genes coding for PI-metabolizing enzymes and effectors may have significant and unappreciated roles in PC. Methods: We generated a CRISPR knockout (KO) library that targets 1,534 PI-associated genes to discover novel essential genes in PC. Results: In a PANC-1 screen, we identified 106 essential genes across all timepoints, including 28 novel candidate genes and 78 previously identified essential genes. Among six validated candidate genes, we demonstrate that Integrin Subunit Alpha V (ITGAV) is a protein with clinical importance in PC. Treatment of PC cell lines with an ITGAV integrin antagonist as well as KO of ITGAV resulted in reduced cancer associated phenotypes in vitro, including reduced proliferation rate and compromised migration and invasion capacity. Ongoing studies will investigate perturbations in signaling pathways associated with ITGAV, and aim to elucidate roles for ITGAV in metastatic progression and therapy response. Conclusions: Overall, these findings indicate that ITGAV inhibition represents a putative strategy for the treatment of PC. Citation Format: Daniel K.C. Lee, Ryan Loke, Lydia To, Keyue Chen, Jonathan T.S. Chow, Leonardo Salmena. Phosphoinositide focused CRISPR screen reveals ITGAV as a critical gene in pancreatic cancer growth and invasion [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer; 2022 Sep 13-16; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2022;82(22 Suppl):Abstract nr B024.

Signaling pathways that control vital features of leukemic stem cells including multipotency, self-renewal, clonal expansion and quiescence remain unclear. Emerging studies illustrate critical roles for lysosomes in hematopoietic and leukemic stem cell fate. By investigating consequences of INPP4B alterations in AML, we have discovered its role in driving leukemic ‘stemness’. We observed that INPP4B is highly expressed leukemic stem cell populations and Inpp4b-deficeint leukemias demonstrate increased disease latency, reduced leukemia initiating potential which is associated with a differentiated leukemic phenotype. Molecular analyses show that Inpp4b-deficient leukemias have compromised lysosomal gene expression, lysosomal content, and lysosomal activity. Our discovery of a novel pathway linking INPP4B, lysosomal biogenesis and leukemic stemness, provides a mechanism to explain the association of high INPP4B expression with poor AML prognosis, and highlights novel patient stratification strategies and LSC-specific leukemic therapies.Key PointsOur findings highlight a novel pathway linking INPP4B, lysosomal function and leukemic stemness that explains the prognostic role of INPP4B in AML.Our data reveal the utility of INPP4B as a biomarker of aggressive AML and provide a rationale to explore INPP4B and its associated function in lysosome biology as novel strategies to target LSC and AML

Acute myeloid leukemia (AML) is an aggressive clonal stem cell disorder characterized by invasion of bone marrow, impaired hematopoiesis and accumulation of functionally immature myeloblasts. Our previous studies demonstrated that the expression level of the lipid phosphatase, INPP4B, is associated with poor outcomes in AML. To gain an understanding of the role of Inpp4b in AML progression, we performed RNA sequencing on Inpp4b+/+ and Inpp4b−/− MLL-AF9 leukemias. Analysis of RNA sequencing data revealed that a disproportionately large number of lysosomal gene transcripts are decreased in Inpp4b−/− leukemias; these include cathepsins and lysosomal specific proteases responsible for proteolysis. This discovery provided evidence supporting a potential role for INPP4B in the lysosomal pathway. To validate these findings, immunofluorescence staining of the lysosomal protein LAMP1 was performed, which revealed a greater number of lysosomes in U2OS cells overexpressing INPP4B, and a decrease in lysosome number upon siRNA knockdown of INPP4B. Subsequently the DQ-BSA staining was used to assess INPP4B’s effect on lysosomal function. In both U2OS and the leukemia cells, we observed that INPP4B expression is positively associated with the proteolytic activity of lysosomes. Currently we are testing the role of INPP4B expression on sensitivity to lysosomal inhibitors; Lys05, Chloroquine, and Mefloquine. Overall, we aim to uncover how INPP4B expression in AML controls lysosomal mechanisms and biology and to test putative therapeutic strategies to exploit this pathway. Citation Format: Keyue Chen, Gizem E. Genc, John F. Woolley, Daniel K.C. Lee, Roberto J. Botelho, Leonardo Salmena. Investigating inositol polyphosphate-4-phosphatase, type II (INPP4B) signaling and role in acute myeloid leukemia [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2021 Oct 7-10. Philadelphia (PA): AACR; Mol Cancer Ther 2021;20(12 Suppl):Abstract nr P175.

Damaged DNA shows increased mobility, which can promote interactions with repair-conducive nuclear pore complexes (NPCs). This apparently random mobility is paradoxically abrogated upon disruption of microtubules or kinesins, factors that typically cooperate to mediate the directional movement of macromolecules. Here, we resolve this paradox by uncovering DNA damage-inducible intranuclear microtubule filaments (DIMs) that mobilize damaged DNA and promote repair. Upon DNA damage, relief of centromeric constraint induces DIMs that cooperate with the Rad9 DNA damage response mediator and Kar3 kinesin motor to capture DNA lesions, which then linearly move along dynamic DIMs. Decreasing and hyper-inducing DIMs respectively abrogates and hyper-activates repair. Accounting for DIM dynamics across cell populations by measuring directional changes of damaged DNA reveals that it exhibits increased non-linear directional behavior in nuclear space. Abrogation of DIM-dependent processes or repair-promoting factors decreases directional behavior. Thus, inducible and dynamic nuclear microtubule filaments directionally mobilize damaged DNA and promote repair., Following DNA damage, different processes come to action to aid repair. The authors here find that microtubule filaments within the cell nucleus capture and non-randomly mobilize damaged chromatin to mediate DNA repair.

DNA double-strand breaks (DSBs) are often targeted to nuclear pore complexes (NPCs) for repair. How targeting is achieved and the DNA repair pathways involved in this process remain unclear. Here, we show that the kinesin-14 motor protein complex (Cik1–Kar3) cooperates with chromatin remodellers to mediate interactions between subtelomeric DSBs and the Nup84 nuclear pore complex to ensure cell survival via break-induced replication (BIR), an error-prone DNA repair process. Insertion of a DNA zip code near the subtelomeric DSB site artificially targets it to NPCs hyperactivating this repair mechanism. Kinesin-14 and Nup84 mediate BIR-dependent repair at non-telomeric DSBs whereas perinuclear telomere tethers are only required for telomeric BIR. Furthermore, kinesin-14 plays a critical role in telomerase-independent telomere maintenance. Thus, we uncover roles for kinesin and NPCs in DNA repair by BIR and reveal that perinuclear telomere anchors license subtelomeric DSBs for this error-prone DNA repair mechanism. Damaged DNA is often targeted to nuclear pore complexes for repair. Here, the authors show that kinesin-14 mediates this process ensuring error-prone repair, while perinuclear telomere attachment licenses damaged telomeric loci for this repair and kinesin-14 blocks senescence in the absence of telomerase.

The extensively documented antiallergic and anti-inflammatory properties of second-generation H 1 -antihistamines further enhance their therapeutic potential in asthma. Modern H 1 -antihistamines such as desloratadine, fexofenadine and levocetirizine, with wider therapeutic windows and similar antiallergic and anti-inflammatory properties as the older compounds, may prove a safer alternative in the treatment of asthma. Further studies are needed to elucidate the role of modern H 1 -antihistamines in asthma management including their use in severe persistent or perennial asthma, and to evaluate their effects on lung function, tolerability at higher doses and long-term safety and efficacy.

Asthma is a worldwide chronic disorder that is characterised by airway inflammation and hyper-responsiveness, which results in intermittent airflow obstruction and subsequent perception of symptoms and exacerbations. Inhaled corticosteroids are a fundamental component in the prevention of the short- and long-term complications associated with inadequately controlled asthma. However, many individuals experience persistent symptoms and exacerbations despite receiving low-to-medium doses of an inhaled corticosteroid (400-800 microg/day of beclometasone or equivalent). In these symptomatic asthmatic patients, guidelines advocate the initiation of a long-acting beta2-adrenoceptor agonist (LABA) as additional second-line controller therapy. The recent SMART (Salmeterol Multi-centre Asthma Research Trial) study was designed to compare the effects of add-on salmeterol 42 microg (ex-actuator) twice daily with placebo over 28 weeks in a randomised, double-blind, parallel-group fashion, with the intention to enrol 60,000 asthmatic patients. However, the study was halted prematurely because preliminary data revealed an increased mortality associated with regular use of salmeterol. Moreover, concerning rates of respiratory-related deaths, asthma-related deaths and life-threatening events were observed among African Americans, who constituted up to 18% of the study population. This in turn prompted the US FDA to announce important safety information regarding inhalers containing LABAs and advise that new labelling be produced outlining the "small but significant risk in asthma-related deaths" associated with their regular use. This evidence-based review discusses the data from SMART and highlights potentially important drawbacks with regular use of LABAs in persistent asthma.

Recording and understanding the behaviour of customers is paramount and a key factor influencing the success of any retail business. This paper reports the initial stages of an EPSRC funded research project, which presents a new methodological approach to analysing in-store customer behaviour with a view to optimising space and store performance. Using existing in-store CCTV cameras from a major clothing discount retailer, consumers are tracked to detect patterns of behaviour. Analysis of these “real-time” data exhibited flaws in the arrangement of customer service facilities, and insight into the problems associated with merchandise return policies. Understanding these customer processes and movement patterns thus helped the retail collaborator maximise the performance of the store.

In this paper, we investigate the price changes and trading volume reactions during the days surrounding the announcements of annual earnings based on a 31-day observation window for a sample of Hong Kong firms listed on the Stock Exchange of Hong Kong (SEHK). The major findings of our study: (1) materially support the findings of Morse (1981) , (2) demonstrate significant price and volume reactions over four days surrounding the annual earnings announcement over the years 1992 to 1995, (3) show similar market reaction for Blue Chip stocks compared to Non–Blue Chip stocks, and (4) indicate a larger overall price reaction for Non–Blue Chip stocks and mixed results regarding volume reaction when comparing the Blue Chip and Non–Blue Chip stocks. These results show that, although the Hong Kong results are largely in line with the U.S. and international evidence, the Blue Chip stocks are followed more and remain the mainstream stocks for Hong Kong investors.

Most of the genome of a eukaryotic cell is located in its nucleus, which is a ball-like entity defined by a membrane bilayer known as the nuclear envelope. Constitutive physical interactions between certain chromosomal domains and inner nuclear membrane proteins can directly promote genome stability and cellular lifespan by preventing aberrant DNA recombination events [1, 2]. In addition, DNA loci experiencing DNA double-strand breaks (DSBs) exhibit increased interactions with nuclear pore complexes at the nuclear envelope and this is thought to contribute to DNA repair [3, 4, 5]. That a change in the subnuclear positioning of a damaged DNA locus may contribute to its repair has been observed in various organisms including yeast and human [3-6]. DSBs changing location may be escaping subnuclear neighbourhoods that are not conducive to repair, moving to specialized regions that directly promote repair, and/or searching for homologous DNA sequences to serve as donors for repair. How DSBs move within the eukaryotic nucleus and what DNA repair pathways are engaged via this movement is unclear. We recently utilized the power of yeast genetics in order to address these questions. We assessed the ability of cells to survive DSBs precisely induced at different locations across the genome and analyzed the chromosomes of cells surviving the DNA break [7]. This analysis revealed that DSBs close to linear chromosome ends, or telomeres, are preferentially repaired via an error-prone type of homologous recombination called break-induced replication (BIR) [7]. Essential to this repair process were inner nuclear membrane proteins that typically work to tether telomeres to the nuclear envelope. Also critical to DSB survival was a particular nuclear pore complex. Abrogating the inner nuclear membrane proteins but not the nuclear pore complex released telomeres from the nuclear envelope in the absence of DNA damage. This is consistent with the fact that yeast telomeres are typically arranged in a handful of clusters abutting the inner nuclear membrane but away from nuclear pore regions. Interestingly however, genetic and molecular biology experiments revealed that DSB induction greatly increases physical interactions between the damaged chromosome ends and nuclear pore complexes. This increased interaction is dependent on perinuclear telomere tethers as well as a kinesin motor protein complex called Kinesin-14. This BIR-dependent DNA repair process was promoted via disruption of chromatin silencing but repressed upon abrogation of chromatin remodelling, DNA damage responses, or microtubule stability. Interestingly, artificially targeting DNA loci to nuclear pore complexes via the use of so-called ‘DNA zip codes’ hyper-activated this DNA repair process. Importantly, repair of a DSB induced at a locus located more internally on the same chromosome arm did not require perinuclear telomere tethers, motor proteins, nuclear pore complexes, or the homologous recombination machinery [7]. Instead, repair of this control site was dependent on non-homologous end joining. In contrast, strong DNA resection near chromosome ends ensures the engagement of homologous recombination/BIR. We also found that kinesin-14 and nuclear pore complexes, but not perinuclear telomere tethers, cooperate to repair nontelomeric DSBs that are repairable via BIR. Monitoring DSB mobility profiles in living cells in combination with molecular biology experiments indicates that Kinesin-14 allows for the transient relocation of DSBs to nuclear pore complexes for repair. BIR is physiologically important for the maintenance of telomeres in the absence of telomerase via a recombination-based mechanism that is akin to the ‘alternative lengthening of telomeres’ seen in telomerasenegative human cancers. Interestingly, we found that Kinesin-14 promotes recombination-based telomere maintenance and limits senescence in the absence of telomerase [7]. Thus, motor proteins can help cells survive stressful events such as DSBs or telomerase loss by engaging DNA recombination pathways that actually promote the propagation of a compromised genome in a cell population, a scenario that commonly leads to cancer. Taken together, our findings indicate that motor proteins can act like a ‘DNA ambulance’ that helps transport damaged DNA to ‘DNA hospitals’, or NPCs [7]. Importantly, this hospital helps repair damaged DNA via an error-prone process that promotes cell survival at the expense of genome fidelity. On a broader level, it is well established that motor proteins perform various critical roles in the cell. This includes the transport of vesicles in the cytoplasm and the movement of chromosomes during cell division. Our study expands the functional repertoire of motor proteins to nuclear DNA repair and the movement of interphase chromosomes. Our work also raises many new and important questions. For example, how do microtubules cooperate with motor proteins to mediate DNA repair? Can motor proteins move interphase chromosomes to regulate other DNA related processes such as replication and gene expression? Can motor proteins transport other nuclear nucleic acids including various types of RNA molecules? If some motor proteins promote cancer by ensuring the propagation of a compromised genome, can this help us develop novel anti-cancer drugs? In conclusion, since most of the macromolecules linked to this novel DNA repair mechanism are evolutionarily conserved, we expect that similar DNA movement and repair processes exist in various organisms.

Inhaled treatment forms the cornerstone of drug management of chronic obstructive pulmonary disease (COPD). However, some patients—especially those who are elderly, cognitively impaired, or with upper limb musculoskeletal problems—are unable to use inhaler devices successfully. Theophylline is one of the oldest oral bronchodilators available for the treatment of COPD. It has a similar chemical structure to caffeine, which is also a bronchodilator in large amounts. Additive effects of theophylline and the bronchodilator salmeterol on lung function in patients with COPD at day 1 and at 12 weeks after starting treatment Theophylline is a non-selective phosphodiesterase inhibitor, and it causes an increase in the intracellular concentration of cyclic AMP in various cell types and organs (including the lung). Increased cyclic AMP concentrations are implicated in inhibition of inflammatory and immunomodulatory cells. One result is that phosphodiesterase inhibition causes smooth muscle relaxation and airway dilation. View this table: Adverse effects of theophylline Other potentially beneficial mechanisms of action of theophylline in COPD have been suggested, including ### Clinical use of theophylline Consider a long acting theophylline preparation in patients with advanced COPD, especially when symptoms persist despite the use of inhaled long acting bronchodilators or in patients unable to use inhaler devices. Studies have shown that theophylline generally …

Seafood-borne illnesses are a common but under recognised source of morbidity. We report the case of an 80-year-old woman who presented to hospital after collapsing in a restaurant following lunch consisting of mackerel fish. A detailed food history and clinical exclusion helped diagnose the condition as scombroid poisoning. The patient made a complete recovery following antihistamine therapy.

This paper presents a workflow specification language developed in the WIDE project. The language provides a rich organisation model, an information model including presentation details, and a sophisticated process model. Workflow application developers should find the language a useful and compact means to capture and investigate design details. Workflow system developers would discover the language a good vehicle to study the interaction between different features as well as facilitate the development of more advanced features. Others would attain a better understanding of the workflow paradigm and could use the language ms a basis of evaluation for the functionality of workflow systems.