RNA-Binding Proteins and Their Emerging Roles in Cancer: Beyond the Tip of the Iceberg.

RNA-binding proteins (RBPs) represent a large family of proteins with an extensive array of roles that contribute to coordinating and directing multiple functions in RNA metabolism and transcription [...].

Asymmetric catalytic formation of quaternary carbons by iminium ion trapping of radicals.

An important goal of modern organic chemistry is to develop new catalytic strategies for enantioselective carbon-carbon bond formation that can be used to generate quaternary stereogenic centres. Whereas considerable advances have been achieved by exploiting polar reactivity, radical transformations have been far less successful. This is despite the fact that open-shell intermediates are intrinsically primed for connecting structurally congested carbons, as their reactivity is only marginally affected by steric factors. Here we show how the combination of photoredox and asymmetric organic catalysis enables enantioselective radical conjugate additions to ß,ß-disubstituted cyclic enones to obtain quaternary carbon stereocentres with high fidelity. Critical to our success was the design of a chiral organic catalyst, containing a redox-active carbazole moiety, that drives the formation of iminium ions and the stereoselective trapping of photochemically generated carbon-centred radicals by means of an electron-relay mechanism. We demonstrate the generality of this organocatalytic radical-trapping strategy with two sets of open-shell intermediates, formed through unrelated light-triggered pathways from readily available substrates and photoredox catalysts--this method represents the application of iminium ion activation (a successful catalytic strategy for enantioselective polar chemistry) within the realm of radical reactivity.

Nickel-Catalyzed Enantioselective Synthesis of Pre-Differentiated Homoallylic syn- or anti-1,2-Diols from Aldehydes and Dienol Ethers.

Nickel catalysis allied with cyclodiphosphazane or VAPOL-derived phosphoramidite ligands provides selective access to monoprotected vicinal diols by reductive coupling of dienol ethers and aldehydes. The observed regioselectivity is unprecedented, in that the diene reacts at the least nucleophilic and most hindered C atom that is attached to the oxygen substituent rather than at the terminal position. Notably, both syn and anti diastereomers of the products can be accessed depending on the configuration of the diene partner with usually excellent diastereo- and enantioselectivity.

AU-Rich Element RNA Binding Proteins: At the Crossroads of Post-Transcriptional Regulation and Genome Integrity.

Genome integrity must be tightly preserved to ensure cellular survival and to deter the genesis of disease. Endogenous and exogenous stressors that impose threats to genomic stability through DNA damage are counteracted by a tightly regulated DNA damage response (DDR). RNA binding proteins (RBPs) are emerging as regulators and mediators of diverse biological processes. Specifically, RBPs that bind to adenine uridine (AU)-rich elements (AREs) in the 3' untranslated region (UTR) of mRNAs (AU-RBPs) have emerged as key players in regulating the DDR and preserving genome integrity. Here we review eight established AU-RBPs (AUF1, HuR, KHSRP, TIA-1, TIAR, ZFP36, ZFP36L1, ZFP36L2) and their ability to maintain genome integrity through various interactions. We have reviewed canonical roles of AU-RBPs in regulating the fate of mRNA transcripts encoding DDR genes at multiple post-transcriptional levels. We have also attempted to shed light on non-canonical roles of AU-RBPs exploring their post-translational modifications (PTMs) and sub-cellular localization in response to genotoxic stresses by various factors involved in DDR and genome maintenance. Dysfunctional AU-RBPs have been increasingly found to be associated with many human cancers. Further understanding of the roles of AU-RBPS in maintaining genomic integrity may uncover novel therapeutic strategies for cancer.

Chagosensine: A Riddle Wrapped in a Mystery Inside an Enigma.

The marine macrolide chagosensine is supposedly distinguished by a (Z,Z)-configured 1,3-chlorodiene contained within a highly strained 16-membered lactone ring, which also incorporates two trans-2,5-disubstituted tetrahydrofuran (THF) rings; this array is unique. After our initial synthesis campaign had shown that the originally proposed structure is incorrect, the published data set was critically revisited to identify potential mis-assignments. The "northern" THF ring and the anti-configured diol in the "southern" sector both seemed to be sites of concern, thus making it plausible that a panel of eight diastereomeric chagosensine-like compounds would allow the puzzle to be solved. To meet the challenge, the preparation of the required building blocks was optimized, and a convergent strategy for their assembly was developed. A key role was played by the cobalt-catalyzed oxidative cyclization of alken-5-ol derivatives ("Mukaiyama cyclization"), which is shown to be exquisitely chemoselective for terminal alkenes, leaving even terminal alkynes (and other sites of unsaturation) untouched. Likewise, a palladium-catalyzed alkyne alkoxycarbonylation reaction with formation of an α-methylene-γ-lactone proved instrumental, which had not found application in natural product synthesis before. Further enabling steps were a nickel-catalyzed "Tamaru-type" homocrotylation, stereodivergent aldehyde homologations, radical hydroindation, and palladium-catalyzed alkyne-1,2-bis-stannation. The different building blocks were assembled in a serial fashion to give the idiosyncratic chlorodienes by an unprecedented site-selective Stille coupling followed by copper-mediated tin/chlorine exchange. The macrolactones were closed under forcing Yamaguchi conditions, and the resulting products were elaborated into the targeted compound library. Yet, only one of the eight diastereomers turned out to be stable in the solvent mixture that had been used to analyze the natural product; all other isomers were prone to ring opening and/or ring expansion. In addition to this stability issue, our self-consistent data set suggests that chagosensine has almost certainly little to do with the structure originally proposed by the isolation team.

Prostate Cancer: The Role of Inflammation and Chemokines.

Prostate cancer (PC) is a leading cause of death in men. Inflammation is one of the initiating processes whereby cells are trafficked into the tumor microenvironment by specific cytokines termed chemokines. This recruitment is complex and involves diverse leukocyte subsets with procancer and anticancer functions. Chemokines promote/abrogate proliferation of cancerous cells, block/aid apoptosis, and are instrumental/detrimental in cancer cell migration required for metastasis. Chemokines guide the release/transport of immune cells that serve as chaperones at sites of inflammation, and after subsequent activation, they lead to an immune response. The variety of immune cells recruited at the site of tumor initiation possess unique functions, and the plethora of chemokines released by each cell derived from a progenitor cell activated under a defined set of conditions dictates its specific role in cancer progression/regression. Geographic consequences that govern the climate and endemic diseases, along with the associated evolutionary effects that at times protect populations from one disease, could lead to genetic variations that determine a role for ethnicity and race in PC risk and susceptibility. Dysregulated expression or an imbalance in the homeostatic mechanisms associated with chemokines is implicated in PC. This review discusses the role of inflammation and chemokines in PC.

Total Synthesis of Putative Chagosensine.

The marine macrolide chagosensine is the only natural product known to date that embodies a Z,Z-configured chloro-1,3-diene unit. This distinguishing substructure was prepared by a sequence of palladium-catalyzed 1,2-distannation of an alkyne precursor, regioselective Stille cross-coupling at the terminus of the resulting bisstannyl alkene with an elaborated alkenyl iodide, followed by chloro-destannation of the remaining internal site. The preparation of the required substrates centered on cobalt-catalyzed oxidative cyclization reactions of hydroxylated olefin precursors, which allowed the 2,5-trans-disubstituted tetrahydrofuran rings, embedded into each building block, to be formed with excellent selectivity. The highly strained macrolactone could ultimately be closed under forcing Yamaguchi conditions. Comparison of the spectral data of the synthetic sample with those of authentic chagosensine methyl ester confirmed that the structure of this intriguing compound has been mis-assigned by the isolation team.

Studies on the Enantioselective Iminium Ion Trapping of Radicals Triggered by an Electron-Relay Mechanism.

A combination of electrochemical, spectroscopic, computational, and kinetic studies has been used to elucidate the key mechanistic aspects of the previously reported enantioselective iminium ion trapping of photochemically generated carbon-centered radicals. The process, which provides a direct way to forge quaternary stereocenters with high fidelity, relies on the interplay of two distinct catalytic cycles: the aminocatalytic electron-relay system, which triggers the stereoselective radical trap upon iminium ion formation, and the photoredox cycle, which generates radicals under mild conditions. Critical to reaction development was the use of a chiral amine catalyst, bearing a redox-active carbazole unit, which could rapidly reduce the highly reactive and unstable intermediate generated upon radical interception. The carbazole unit, however, is also involved in another step of the electron-relay mechanism: the transiently generated carbazole radical cation acts as an oxidant to return the photocatalyst into the original state. By means of kinetic and spectroscopic studies, we have identified the last redox event as being the turnover-limiting step of the overall process. This mechanistic framework is corroborated by the linear correlation between the reaction rate and the reduction potential of the carbazole unit tethered to the aminocatalyst. The redox properties of the carbazole unit can thus be rationally tuned to improve catalytic activity. This knowledge may open a path for the mechanistically driven design of the next generation of electron-relay catalysts.

A dismantling study of the Partners for Change Outcome Management System.

The current study used a dismantling design to investigate the relative efficacy of components of the Partners for Change Outcome Management System (PCOMS; Duncan, 2012). Clients (n = 94) from a university counseling center were randomly assigned to 1 of 3 conditions: PCOMS Full, Outcome Rating Scale (ORS)-only, or Session Rating Scale (SRS)-only and nested within therapists (n = 12). Results from hierarchical linear modeling and a 2-way analysis of variance indicated no statistically significant differences in outcome or rate of change on the Behavior Symptom Checklist-18 (BSI-18; Derogatis, 2001) across all 3 conditions. These findings suggest that using either the ORS or SRS component of the PCOMS may yield equivalent outcomes to that of the full PCOMS. Additional dismantling studies with various populations and settings are needed to further clarify the relative influence of the ORS, SRS, and full PCOMS on client outcomes. (PsycINFO Database Record

Photo-organocatalytic Enantioselective Perfluoroalkylation of ß-Ketoesters.

The visible-light-driven, phase-transfer-catalyzed, enantioselective perfluoroalkylation and trifluoromethylation of cyclic ß-ketoesters is described. The photo-organocatalytic process, which occurs at ambient temperature and under visible light illumination, is triggered by the photochemical activity of in situ-generated electron donor-acceptor complexes, arising from the association of chiral enolates and perfluoroalkyl iodides. Preliminary mechanistic studies are reported.

AU-rich RNA binding proteins in hematopoiesis and leukemogenesis.

Posttranscriptional mechanisms are now widely acknowledged to play a central role in orchestrating gene-regulatory networks in hematopoietic cell growth, differentiation, and tumorigenesis. Although much attention has focused on microRNAs as regulators of mRNA stability/translation, recent data have highlighted the role of several diverse classes of AU-rich RNA-binding protein in the regulation of mRNA decay/stabilization. AU-rich elements are found in the 3'-untranslated region of many mRNAs that encode regulators of cell growth and survival, such as cytokines and onco/tumor-suppressor proteins. These are targeted by a burgeoning number of different RNA-binding proteins. Three distinct types of AU-rich RNA binding protein (ARE poly-U-binding degradation factor-1/AUF1, Hu antigen/HuR/HuA/ELAVL1, and the tristetraprolin/ZFP36 family of proteins) are essential for normal hematopoiesis. Together with 2 further AU-rich RNA-binding proteins, nucleolin and KHSRP/KSRP, the functions of these proteins are intimately associated with pathways that are dysregulated in various hematopoietic malignancies. Significantly, all of these AU-rich RNA-binding proteins function via an interconnected network that is integrated with microRNA functions. Studies of these diverse types of RNA binding protein are providing novel insight into gene-regulatory mechanisms in hematopoiesis in addition to offering new opportunities for developing mechanism-based targeted therapeutics in leukemia and lymphoma.

A deep learning workflow for quantification of micronuclei in DNA damage studies in cultured cancer cell lines: A proof of principle investigation.

The cytokinesis block micronucleus assay is widely used for measuring/scoring/counting micronuclei, a marker of genome instability in cultured and primary cells. Though a gold standard method, this is a laborious and time-consuming process with person-to-person variation observed in quantification of micronuclei. We report in this study the utilisation of a new deep learning workflow for detection of micronuclei in DAPI stained nuclear images. The proposed deep learning framework achieved an average precision of >90% in detection of micronuclei. This proof of principle investigation in a DNA damage studies laboratory supports the idea of deploying AI powered tools in a cost-effective manner for repetitive and laborious tasks with relevant computational expertise. These systems will also help improving the quality of data and wellbeing of researchers.

Veteran and Staff Experience from a Pilot Program of Health Care System-Distributed Wearable Devices and Data Sharing.

OBJECTIVE: The growing trend to use wearable devices to track activity and health data has the potential to positively impact the patient experience with their health care at home and with their care team. As part of a pilot program, the U.S. Department of Veterans Affairs (VA) distributed Fitbits to Veterans through four VA medical centers. Our objective was to assess the program from both Veterans' and clinicians' viewpoints. Specifically, we aimed to understand barriers to Fitbit setup and use for Veterans, including syncing devices with a VA mobile application (app) to share data, and assess the perceived value of the device functions and ability to share information from the Fitbit with their care team. In addition, we explored the clinicians' perspective, including how they expected to use the patient-generated health data (PGHD). METHODS: We performed semi-structured interviews with 26 Veterans and 16 VA clinicians to assess the program. Responses to each question were summarized in order of frequency of occurrence across participants and audited by an independent analyst for accuracy. RESULTS: Our findings reveal that despite setup challenges, there is support for the use of Fitbits to engage Veterans and help manage their health. Clinicians believed there were benefits for having Veterans use the Fitbits and expected to use the PGHD in a variety of ways as part of the Veterans' care plans, including monitoring progress toward health behavior goals. Veterans were overwhelmingly enthusiastic about using the Fitbits; this enthusiasm seems to extend beyond the 3 month "novelty period." CONCLUSION: The pilot program for distributing Fitbits to Veterans appears to be successful from both Veterans' and clinicians' perspectives and suggests that expanded use of wearable devices should be considered. Future studies will need to carefully consider how to incorporate the PGHD into the electronic health record and clinical workflow.

Veterans' response to an automated text messaging protocol during the COVID-19 pandemic.

The US Department of Veterans Affairs (VA) is using an automated short message service application named "Annie" as part of its coronavirus disease 2019 (COVID-19) response with a protocol for coronavirus precautions, which can help the veteran monitor symptoms and can advise the veteran when to contact his or her VA care team or a nurse triage line. We surveyed 1134 veterans on their use of the Annie application and coronavirus precautions protocol. Survey results support what is likely a substantial resource savings for the VA, as well as non-VA community healthcare. Moreover, the majority of veterans reported at least 1 positive sentiment (felt more connected to VA, confident, or educated and/or felt less anxious) by receiving the protocol messages. The findings from this study have implications for other healthcare systems to help manage a patient population during the coronavirus pandemic.

Negative energy balance alters global gene expression and immune responses in the uterus of postpartum dairy cows.

Most dairy cows suffer uterine microbial contamination postpartum. Persistent endometritis often develops, associated with reduced fertility. We used a model of differential feeding and milking regimes to produce cows in differing negative energy balance status in early lactation (mild or severe, MNEB or SNEB). Blood hematology was assessed preslaughter at 2 wk postpartum. RNA expression in endometrial samples was compared using bovine Affymetrix arrays. Data were mapped using Ingenuity Pathway Analysis. Circulating concentrations of IGF-I remained lower in the SNEB group, whereas blood nonesterified fatty acid and beta-hydroxybutyrate concentrations were raised. White blood cell count and lymphocyte number were reduced in SNEB cows. Array analysis of endometrial samples identified 274 differentially expressed probes representing 197 recognized genes between the energy balance groups. The main canonical pathways affected related to immunological and inflammatory disease and connective tissue disorders. Inflammatory response genes with major upregulation in SNEB cows included matrix metalloproteinases, chemokines, cytokines, and calgranulins. Expression of several interferon-inducible genes including ISG20, IFIH1, MX1, and MX2 were also significantly increased in the SNEB cows. These results provide evidence that cows in SNEB were still undergoing an active uterine inflammatory response 2 wk postpartum, whereas MNEB cows had more fully recovered from their energy deficit, with their endometrium reaching a more advanced stage of repair. SNEB may therefore prevent cows from mounting an effective immune response to the microbial challenge experienced after calving, prolonging the time required for uterine recovery and compromising subsequent fertility.

TIS11 family proteins and their roles in posttranscriptional gene regulation.

Posttranscriptional regulation of gene expression of mRNAs containing adenine-uridine rich elements (AREs) in their 3' untranslated regions is mediated by a number of different proteins that interact with these elements to either stabilise or destabilise them. The present review concerns the TPA-inducible sequence 11 (TIS11) protein family, a small family of proteins, that appears to interact with ARE-containing mRNAs and promote their degradation. This family of proteins has been extensively studied in the past decade. Studies have focussed on determining their biochemical functions, identifying their target mRNAs, and determining their roles in cell functions and diseases.

Interrelationships between negative energy balance (NEB) and IGF regulation in liver of lactating dairy cows.

In dairy cows, negative energy balance (NEB) during the early post-partum period is associated with major alterations in the growth hormone-insulin-like growth factor (GH-IGF) axis. Since the liver mediates nutrient partitioning during lactation, we aimed to determine how NEB alters the endocrine regulation of the insulin-like growth factor (IGF) system by investigating the expression of IGF family members and related steroid receptors. On the second day of lactation, cows were allocated to one of two treatments designed to produce mild (MNEB) or severe NEB (SNEB). MNEB cows (n=5) were fed ad lib grass silage supplemented with concentrate and milked x1 daily and SNEB cows (n=6) were restricted in dietary intake and milked x3 daily. Energy balance (EB) status was monitored until the second week of lactation when plasma and liver samples revealed a markedly divergent metabolic profile. At this time, plasma protein and hepatic mRNA for IGF-I was reduced in SNEB cows compared with MNEB cows. Both levels of expression correlated highly when data from all animals was pooled (r=0.963; P<0.01). SNEB cows also exhibited reduced hepatic expression for transcripts encoding IGF-1R, IGF-2R, IGF binding proteins (IGFBPs) -3, -4, -5, -6, acid labile subunit, and receptors for oestrogen (ERalpha) and growth hormone (total GHR and 1A variant), while the expression of IGFBP-2 was elevated. Expression of mRNA for IGF-II, IGFBP-1 and receptors for insulin (A/B) and glucocorticoid (alpha) was unaffected by EB. Results demonstrate that SNEB affects hepatic synthesis of IGF-I, and other components known to modulate the bioavailability and stability of circulating IGF-I.

A randomized controlled trial of financial incentives for smoking cessation.

BACKGROUND: Although 435,000 Americans die each year of tobacco-related illness, only approximately 3% of smokers quit each year. Financial incentives have been shown to be effective in modifying behavior within highly structured settings, such as drug treatment programs, but this has not been shown in treating chronic disease in less structured settings. The objective of this study was to determine whether modest financial incentives increase the rate of smoking cessation program enrollment, completion, and quit rates in a outpatient clinical setting. METHODS: 179 smokers at the Philadelphia Veterans Affairs Medical Center who reported smoking at least 10 cigarettes per day were randomized into incentive and non-incentive groups. Both groups were offered a free five-class smoking cessation program at the Philadelphia Veterans Affairs Medical Center. The incentive group was also offered $20 for each class attended and $100 if they quit smoking 30 days post program completion. Self-reported smoking cessation was confirmed with urine cotinine tests. RESULTS: The incentive group had higher rates of program enrollment (43.3% versus 20.2%; P<0.001) and completion (25.8% versus 12.2%; P=0.02). Quit rates at 75 days were 16.3% in the incentive group versus 4.6% in the control group (P=0.01). At 6 months, quit rates in the incentive group were not significantly higher (6.5%) than in the control group (4.6%; P>0.20). CONCLUSION: Modest financial incentives are associated with significantly higher rates of smoking cessation program enrollment and completion and short-term quit rates. Future studies should consider including an incentive for longer-term cessation.