Development and internal validation of a predictive risk model for anxiety after completion of treatment for early stage breast cancer

Objective To develop a predictive risk model (PRM) for patient-reported anxiety after treatment completion for early stage breast cancer suitable for use in practice and underpinned by advances in data science and risk prediction. Methods Secondary analysis of a prospective survey of > 800 women at the end of treatment and again 6 months later using patient reported outcome (PRO) the hospital anxiety and depression scale-anxiety (HADS-A) and > 20 candidate predictors. Multiple imputation using chained equations (for missing data) and least absolute shrinkage and selection operator (LASSO) were used to select predictors. Final multivariable linear model performance was assessed (R2) and bootstrapped for internal validation. Results Five predictors of anxiety selected by LASSO were HADS-A (Beta 0.73; 95% CI 0.681, 0.785); HAD-depression (Beta 0.095; 95% CI 0.020, 0.182) and having caring responsibilities (Beta 0.488; 95% CI 0.084, 0.866) increased risk, whereas being older (Beta − 0.010; 95% CI -0.028, 0.004) and owning a home (Beta 0.432; 95% CI -0.954, 0.078) reduced the risk. The final model explained 60% of variance and bias was low (− 0.006 to 0.002). Conclusions Different modelling approaches are needed to predict rather than explain patient reported outcomes. We developed a parsimonious and pragmatic PRM. External validation is required prior to translation to digital tool and evaluation of clinical implementation. The routine use of PROs and data driven PRM in practice provides a new opportunity to target supportive care and specialist interventions for cancer patients

Progressive genetic aberrations detected by comparative genomic hybridization in squamous cell cervical cancer

Genetic changes orchestrated by human papillomaviruses are the most important known factors in carcinogenesis of the uterine cervix. However, it is clear that additional genetic events are necessary for tumour progression. We have used comparative genomic hybridization to document non-random chromosomal gains and losses within a subset of 37 cervical carcinomas matched for clinical stage Ib, but with different lymph node status. There were significantly more chromosomal changes in the primary tumours when the lymph nodes were positive for metastases. The most frequent copy number alterations were loss of 3p, 11q, 6q and 10q and gain of 3q. The smallest areas of loss and gain on chromosome 3 were 3p14–22 and 3q24–26. The study identifies progressive DNA copy number changes associated with early-stage invasive cervical cancers with and without lymph node metastases, a factor of potential prognostic and therapeutic value. © 2000 Cancer Research Campaign http://www.bjcancer.co

Genetic aberrations detected by comparative genomic hybridisation in vulvar cancers

Squamous cell carcinoma of the vulva is a disease of significant clinical importance, which arises in the presence or absence of human papillomavirus. We used comparative genomic hybridisation to document non-random chromosomal gains and losses within human papillomavirus positive and negative vulvar cancers. Gain of 3q was significantly more common in human papillomavirus-positive cancers compared to human papillomavirus-negative cancers. The smallest area of gain was 3q22–25, a chromosome region which is frequently gained in other human papillomavirus-related cancers. Chromosome 8q was more commonly gained in human papillomavirus-negative compared to human papillomavirus-positive cancers. 8q21 was the smallest region of gain, which has been identified in other, non-human papillomavirus-related cancers. Chromosome arms 3p and 11q were lost in both categories of vulvar cancer. This study has demonstrated chromosome locations important in the development of vulvar squamous cell carcinoma. Additionally, taken together with previous studies of human papillomavirus-positive cancers of other anogenital sites, the data indicate that one or more oncogenes important in the development and progression of human papillomavirus-induced carcinomas are located on 3q. The different genetic changes seen in human papillomavirus-positive and negative vulvar squamous cell carcinomas support the clinicopathological data indicating that these are different cancer types

pH-Responsive diblock copolymers with two different fluorescent labels for simultaneous monitoring of micellar self-assembly and degree of protonation

We report the synthesis of a novel amphiphilic pH-responsive diblock copolymer labeled with two different fluorophores. This copolymer comprises a water-soluble poly(glycerol monomethacrylate) [PGMA] block and a pH-responsive poly(2-(diisopropylamino)ethyl methacrylate) [PDPA] block. Pyrene methacrylate [PyMA] is statistically copolymerized with glycerol monomethacrylate (GMA) to introduce a suitable fluorescent label. The chain-ends of the PDPA block are labelled using cresyl violet perchlorate [CV] by exploiting the spin trap properties of this dye molecule. Below pH 6, fluorescence from both dye labels can be detected, but deprotonation of the PDPA block between pH 6 and 7 leads to strong attenuation of the CV fluorescence owing to formation of a charge transfer complex with the tertiary amine units in the PDPA block. Therefore, changes in the Cresyl Violet fluorescence intensity can be correlated to changes in PDPA protonation. Diblock copolymer self-assembly to form PDPA-core aggregates occurs under these conditions, leading to pyrene fluorescence at an excitation wavelength of 405 nm. This allows direct measurement of chain aggregation, whereas using pH-responsive dyes is simply a measure of the degree of protonation. Here we focus on the synthesis and characterisation of dual-labeled copolymers and their spectroscopic properties in different environments. Finally, we show that using CV as a spin trap provides a convenient and versatile route to fluorescently-labeled copolymers prepared by either RAFT or ATRP. Moreover, this cost-effective dye fluoresces in the red part of the visible spectrum at both neutral and acidic pH

Refractive index matched, nearly hard polymer colloids

Refractive index matched particles serve as essential model systems for colloid scientists, providing nearly hard spheres to explore structure and dynamics. The poly(methyl methacrylate) latexes typically used are often refractive index matched by dispersing them in binary solvent mixtures, but this can lead to undesirable changes, such as particle charging or swelling. To avoid these shortcomings, we have synthesized refractive index matched colloids using polymerization-induced self-assembly (PISA) rather than as polymer latexes. The crucial difference is that these diblock copolymer nanoparticles consist of a single core-forming polymer in a single non-ionizable solvent. The diblock copolymer chosen was poly(stearyl methacrylate)-poly(2,2,2trifluoroethyl methacrylate) (PSMA-PTFEMA), which self-assembles to form PTFEMA core spheres in n-alkanes. By monitoring scattered light intensity, n-tetradecane was found to be the optimal solvent for matching the refractive index of such nanoparticles. As expected for PISA syntheses, the diameter of the colloids can be controlled by varying the PTFEMA degree of polymerization. Concentrated dispersions were prepared, and the diffusion of the PSMA-PTFEMA nanoparticles as a function of volume fraction was measured. These diblock copolymer nanoparticles are a promising new system of transparent spheres for future colloidal studies

Polydimethylsiloxane-Based Diblock Copolymer Nano-objects Prepared in Nonpolar Media via RAFT-Mediated Polymerization-Induced Self-Assembly

Monocarbinol-functionalized polydimethylsiloxane (PDMS; mean degree of polymerization = 66) was converted via esterification into a chain transfer agent (CTA) for reversible addition–fragmentation chain transfer (RAFT) polymerization. The degree of esterification was determined to be 94 ± 1% by 1H NMR spectroscopy and 92 ± 1% by UV absorption spectroscopy. This PDMS CTA was then utilized for the dispersion polymerization of benzyl methacrylate (BzMA) in n-heptane at 70 °C. As the PBzMA block grows, it becomes insoluble in the reaction medium, which drives the in situ formation of PDMS–PBzMA diblock copolymer nanoparticles via polymerization-induced self-assembly (PISA). Depending on the precise reaction conditions, the final diblock copolymer chains can self-assemble to form spheres, worms, or vesicles. Systematic variation of the copolymer concentration and the target degree of polymerization (DP) of the PBzMA block enables construction of a phase diagram that allows the reproducible targeting of pure copolymer morphologies, as judged by transmission electron microscopy and dynamic light scattering studies. 1H NMR spectroscopy studies confirm that relatively high BzMA conversions (>90%) can be achieved within 8 h at 70 °C. Gel permeation chromatography studies (THF eluent) indicate high blocking efficiencies and relatively low final polydispersities (Mw/Mn = 1.14–1.34). Small-angle X-ray scattering (SAXS) has been used to characterize selected examples of the spherical nanoparticles in order to obtain volume-average diameters, which increase monotonically when targeting longer DPs for the core-forming PBzMA block. A relatively high copolymer concentration (>25% w/v) is required to obtain a pure worm phase, which occupies an extremely narrow region within the phase diagram. Selected worm and vesicle dispersions were also analyzed by SAXS, which enables determination of the mean worm cross section, mean worm length and vesicle membrane thickness. In addition, the highly anisotropic worms formed free-standing gels in n-heptane, with rheology measurements indicating viscoelastic behavior and a gel storage modulus of around 104 Pa

Investigating the adsorption of anisotropic diblock copolymer worms onto planar silica and nanocellulose surfaces using a quartz crystal microbalance

Electrostatic adsorption of cationic polyelectrolytes onto anionic cellulosic substrates is an attractive route for facile surface modification of biorenewable materials. Recently, attention has focused on adsorbing cationic spherical diblock copolymer nanoparticles onto model cellulose and/or nanocellulosic substrates. Herein, we investigate physical adsorption of highly anisotropic copolymer worms bearing either anionic or cationic charge onto planar silica, cellulose nanocrystal (CNC) or cellulose nanofibril (CNF) surfaces using quartz crystal microbalance with dissipation monitoring. Electrostatic interactions dominate in the case of anionic silica and CNC surfaces because the adsorbed mass of cationic worms was greater than that of anionic worms. However, either anionic or cationic worms could be adsorbed onto in situ generated CNF substrates, suggesting that additional interactions were involved: hydrogen bonding, van der Waals forces, and possibly covalent bond formation. Scanning electron and atomic force microscopy studies of the dried planar substrates after adsorption experiments confirmed the presence of adsorbed copolymer worms. Finally, composite worm/CNF films exhibited restricted swelling behavior when immersed in water compared to reference CNF films, suggesting that the worms reinforce CNF films by acting as a physical crosslinker. This study is the first investigation of the physical adsorption of highly anisotropic diblock copolymer worms onto cellulosic surfaces

Determining the Effective Density and Stabilizer Layer Thickness of Sterically Stabilized Nanoparticles.

A series of model sterically stabilized diblock copolymer nanoparticles has been designed to aid the development of analytical protocols in order to determine two key parameters: the effective particle density and the steric stabilizer layer thickness. The former parameter is essential for high resolution particle size analysis based on analytical (ultra)centrifugation techniques (e.g., disk centrifuge photosedimentometry, DCP), whereas the latter parameter is of fundamental importance in determining the effectiveness of steric stabilization as a colloid stability mechanism. The diblock copolymer nanoparticles were prepared via polymerization-induced self-assembly (PISA) using RAFT aqueous emulsion polymerization: this approach affords relatively narrow particle size distributions and enables the mean particle diameter and the stabilizer layer thickness to be adjusted independently via systematic variation of the mean degree of polymerization of the hydrophobic and hydrophilic blocks, respectively. The hydrophobic core-forming block was poly(2,2,2-trifluoroethyl methacrylate) [PTFEMA], which was selected for its relatively high density. The hydrophilic stabilizer block was poly(glycerol monomethacrylate) [PGMA], which is a well-known non-ionic polymer that remains water-soluble over a wide range of temperatures. Four series of PGMA x -PTFEMA y nanoparticles were prepared (x = 28, 43, 63, and 98, y = 100-1400) and characterized via transmission electron microscopy (TEM), dynamic light scattering (DLS), and small-angle X-ray scattering (SAXS). It was found that the degree of polymerization of both the PGMA stabilizer and core-forming PTFEMA had a strong influence on the mean particle diameter, which ranged from 20 to 250 nm. Furthermore, SAXS was used to determine radii of gyration of 1.46 to 2.69 nm for the solvated PGMA stabilizer blocks. Thus, the mean effective density of these sterically stabilized particles was calculated and determined to lie between 1.19 g cm(-3) for the smaller particles and 1.41 g cm(-3) for the larger particles; these values are significantly lower than the solid-state density of PTFEMA (1.47 g cm(-3)). Since analytical centrifugation requires the density difference between the particles and the aqueous phase, determining the effective particle density is clearly vital for obtaining reliable particle size distributions. Furthermore, selected DCP data were recalculated by taking into account the inherent density distribution superimposed on the particle size distribution. Consequently, the true particle size distributions were found to be somewhat narrower than those calculated using an erroneous single density value, with smaller particles being particularly sensitive to this artifact

In Situ Small-Angle X-ray Scattering Studies During Reversible Addition–Fragmentation Chain Transfer Aqueous Emulsion Polymerization

Polymerization-induced self-assembly (PISA) is a powerful platform technology for the rational and efficient synthesis of a wide range of block copolymer nano-objects (e.g., spheres, worms or vesicles) in various media. In situ small-angle X-ray scattering (SAXS) studies of reversible addition–fragmentation chain transfer (RAFT) dispersion polymerization have previously provided detailed structural information during self-assembly (see M. J. Derry et al., Chem. Sci. 2016, 7, 5078–5090). However, conducting the analogous in situ SAXS studies during RAFT aqueous emulsion polymerizations poses a formidable technical challenge because the inherently heterogeneous nature of such PISA formulations requires efficient stirring to generate sufficiently small monomer droplets. In the present study, the RAFT aqueous emulsion polymerization of 2-methoxyethyl methacrylate (MOEMA) has been explored for the first time. Chain extension of a relatively short non-ionic poly(glycerol monomethacrylate) (PGMA) precursor block leads to the formation of sterically-stabilized PGMA-PMOEMA spheres, worms or vesicles, depending on the precise reaction conditions. Construction of a suitable phase diagram enables each of these three morphologies to be reproducibly targeted at copolymer concentrations ranging from 10 to 30% w/w solids. High MOEMA conversions are achieved within 2 h at 70 °C, which makes this new PISA formulation well-suited for in situ SAXS studies using a new reaction cell. This bespoke cell enables efficient stirring and hence allows in situ monitoring during RAFT emulsion polymerization for the first time. For example, the onset of micellization and subsequent evolution in particle size can be studied when preparing PGMA29-PMOEMA30 spheres at 10% w/w solids. When targeting PGMA29-PMOEMA70 vesicles under the same conditions, both the micellar nucleation event and the subsequent evolution in the diblock copolymer morphology from spheres to worms to vesicles are observed. These new insights significantly enhance our understanding of the PISA mechanism during RAFT aqueous emulsion polymerization

RESTORE: an exploratory trial of an online intervention to enhance self-efficacy to manage problems associated with cancer-related fatigue following primary cancer treatment: study protocol for a randomized controlled trial

Background: There are over 25 million people worldwide living with or beyond cancer and this number is increasing. Cancer survivors face a range of problems following primary treatment. One of the most frequently reported and distressing symptoms experienced by cancer survivors is fatigue. There is growing support for survivors who are experiencing problems after cancer treatment to engage in supported self-management. To date there is some evidence of effective interventions to manage fatigue in this population; however, to our knowledge there are no online resources that draw on this information to support self-management of fatigue. This paper describes the protocol for an exploratory randomized controlled trial of an online intervention to support self-management of cancer-related fatigue after primary cancer treatment.Methods/design: This is a parallel-group two-armed (1:1) exploratory randomized controlled trial including 125 cancer survivors experiencing fatigue (scoring ≥4 on a unidimensional 11-point numeric rating scale for fatigue intensity) within five years of primary treatment completion with curative intent. Participants will be recruited from 13 NHS Trusts across the UK and randomized to either the online intervention (RESTORE), or a leaflet comparator (Macmillan Cancer Backup, Coping with Fatigue). The primary outcome is a change in Perceived Self-Efficacy for Fatigue Self-Management (as measured by the Perceived Self-Efficacy for Fatigue Self-Management Instrument). Secondary outcomes include impact on perception and experience of fatigue (measured by the Brief Fatigue Inventory), and quality of life (measured by the Functional Assessment of Cancer Therapy - General and the Personal Wellbeing Index). Outcome measures will be collected at baseline, 6 weeks (completion of intervention), and 3 months. Process evaluation (including telephone interviews with recruiting staff and participants) will determine acceptability of the intervention and trial processes.Discussion: Data from this trial will be used to refine the intervention and contribute to the design of an effectiveness trial. This intervention will be expanded to address other cancer-related problems important to cancer survivors following primary cancer treatment