Circulating tryptophan-kynurenine pathway metabolites are associated with all-cause mortality among patients with stage I-III colorectal cancer.

Alterations within the tryptophan-kynurenine metabolic pathway have been linked to the etiology of colorectal cancer (CRC), but the relevance of this pathway for prognostic outcomes in CRC patients needs further elucidation. Therefore, we investigated associations between circulating concentrations of tryptophan-kynurenine pathway metabolites and all-cause mortality among CRC patients. This study utilizes data from 2102 stage I-III CRC patients participating in six prospective cohorts involved in the international FOCUS Consortium. Preoperative circulating concentrations of tryptophan, kynurenine, kynurenic acid (KA), 3-hydroxykynurenine (HK), xanthurenic acid (XA), 3-hydroxyanthranilic acid (HAA), anthranilic acid (AA), picolinic acid (PA), and quinolinic acid (QA) were measured by liquid chromatography-tandem mass spectrometry. Using Cox proportional hazards regression, we examined associations of above-mentioned metabolites with all-cause mortality, adjusted for potential confounders. During a median follow-up of 3.2 years (interquartile range: 2.2-4.9), 290 patients (13.8%) deceased. Higher blood concentrations of tryptophan, XA, and PA were associated with a lower risk of all-cause mortality (per doubling in concentrations: tryptophan: HR = 0.56; 95%CI:0.41,0.76, XA: HR = 0.74; 95%CI:0.64,0.85, PA: HR = 0.76; 95%CI:0.64,0.92), while higher concentrations of HK and QA were associated with an increased risk of death (per doubling in concentrations: HK: HR = 1.80; 95%CI:1.47,2.21, QA: HR = 1.31; 95%CI:1.05,1.63). A higher kynurenine-to-tryptophan ratio, a marker of cell-mediated immune activation, was associated with an increased risk of death (per doubling: HR = 2.07; 95%CI:1.52,2.83). In conclusion, tryptophan-kynurenine pathway metabolites may be prognostic markers of survival in CRC patients.

Statin use and risks of breast cancer recurrence and mortality.

BACKGROUND: Preclinical evidence suggests improved breast cancer survival associated with statin use, but findings from observational studies are conflicting and remain inconclusive. The objective of this study was to assess the association between statin use after cancer diagnosis and cancer outcomes among breast cancer patients. METHODS: In this retrospective cohort study, 38,858 women aged ≥66 years who were diagnosed with localized and regional stage breast cancer from 2008 through 2017 were identified from the linked Surveillance, Epidemiology, and End Results Medicare database. Statin use was ascertained from Medicare Part D pharmacy claims data. Multivariable Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between post-diagnosis statin use and risks of breast cancer recurrence and breast cancer-specific mortality. RESULTS: Over a median follow-up of 2.9 years for recurrence and 3.7 years for mortality, 1446 women experienced a recurrence, and 2215 died from breast cancer. The mean duration of post-diagnosis statin use was 2.2 years. Statin use post-diagnosis was not associated with recurrence risk (HR, 1.05; 95% CI, 0.91-1.21), but was associated with a reduced risk of cancer-specific mortality (HR, 0.85; 95% CI, 0.75-0.96). The reduction was more pronounced in women with hormone receptor-positive/human epidermal growth factor receptor 2-negative breast cancer (HR, 0.71; 95% CI, 0.57-0.88). CONCLUSIONS: These findings suggest that post-diagnosis statin use is associated with improved cancer-specific survival in women with breast cancer and should be confirmed in randomized trials of statin therapy in breast cancer patients.

Assessing sociodemographic and regional disparities in Oncotype DX Genomic Prostate Score uptake.

BACKGROUND: The Oncotype DX Genomic Prostate Score (ODX-GPS) is a gene expression assay that predicts disease aggressiveness. The objective of this study was to identify sociodemographic and regional factors associated with ODX-GPS uptake. METHODS: Data from Surveillance Epidemiology and End Results registries on men with localized prostate cancer with a Gleason score of 3 + 3 or 3 + 4, PSA ≤20 ng/mL, and stage T1c to T2c disease from 2013 through 2017 were linked with ODX-GPS data. Census-tract level neighborhood socioeconomic status (nSES) quintiles were constructed using a composite socioeconomic score. Multivariable logistic regression was used to estimate the associations of ODX-GPS uptake with age at diagnosis, race and ethnicity, nSES, geographic region, insurance type, and marital status, accounting for National Comprehensive Cancer Network risk group, year of diagnosis, and clustering by census tract. RESULTS: Among 111,434 eligible men, 5.5% had ODX-GPS test uptake. Of these, 78.3% were non-Hispanic White, 9.6% were Black, 6.7% were Hispanic, and 3.6% were Asian American. Black men had the lowest odds of ODX-GPS uptake (odds ratio, 0.70; 95% confidence interval [CI], 0.63-0.76). Those in the highest versus lowest quintile of nSES were 1.64 times more likely (95% CI, 1.38-2.94) to have ODX-GPS uptake. The odds of ODX-GPS uptake were statistically significantly higher among men residing in the Northeast, West, and Midwest compared to the South. CONCLUSIONS: Disparities in ODX-GPS uptake by race, ethnicity, nSES, and geographical region were identified. Concerted efforts should be made to ensure that this clinical test is equitably available.

Association between racial residential segregation and screening uptake for colorectal and cervical cancer among Black and White patients in five US health care systems.

BACKGROUND: Despite increased recognition that structural racism contributes to poorer health outcomes for racial and ethnic minorities, there are knowledge gaps about how current patterns of racial residential segregation are associated with cancer screening uptake. The authors examined associations between Black residential segregation and screening for colorectal cancer (CRC) and cervical cancer among non-Hispanic Black and non-Hispanic White adults. METHODS: This was a retrospective study of CRC and cervical cancer screening-eligible adults from five health care systems within the Population-Based Research to Optimize the Screening Process (PROSPR II) Consortium (cohort entry, 2010-2012). Residential segregation was measured using site-specific quartiles of the Black local isolation score (LIS). The outcome was receipt of CRC or cervical cancer screening within 3 years of cohort entry (2010-2015). Logistic regression was used to calculate associations between the LIS and screening completion, adjusting for patient-level covariates. RESULTS: Among CRC (n = 642,661) and cervical cancer (n = 163,340) screening-eligible patients, 456,526 (71.0%) and 106,124 (65.0%), respectively, received screening. Across PROSPR sites, living in neighborhoods with higher LIS tended to be associated with lower odds of CRC screening (Kaiser Permanente Northern California: adjusted odds ratio [aOR] LIS trend in Black patients, 0.95 [p < .001]; aOR LIS trend in White patients, 0.98 [p < .001]; Kaiser Permanente Southern California: aOR LIS trend in Black patients, 0.98 [p = .026]; aOR LIS trend in White patients, 1.01 [p = .023]; Kaiser Permanente Washington: aOR LIS trend in White patients, 0.97 [p = .002]. However, for cervical cancer screening, associations with the LIS varied by site and race (Kaiser Permanente Washington: aOR LIS trend in White patients, 0.95 [p < .001]; Mass General Brigham: aOR LIS trend in Black patients, 1.12 [p < .001]; aOR LIS trend in White patients, 1.03 [p < .001]). CONCLUSIONS: Across five diverse health care systems, the direction of the association between Black residential segregation and screening varied by PROSPR site, race, and screening type. Additional research, including studies that examine multiple dimensions of segregation and structural racism using intersectional approaches, are needed to further disentangle these relationships.

Allometric versus traditional body-shape indices and risk of colorectal cancer: a Mendelian randomization analysis.

BACKGROUND: Traditional body-shape indices such as Waist Circumference (WC), Hip Circumference (HC), and Waist-to-Hip Ratio (WHR) are associated with colorectal cancer (CRC) risk, but are correlated with Body Mass Index (BMI), and adjustment for BMI introduces a strong correlation with height. Thus, new allometric indices have been developed, namely A Body Shape Index (ABSI), Hip Index (HI), and Waist-to-Hip Index (WHI), which are uncorrelated with weight and height; these have also been associated with CRC risk in observational studies, but information from Mendelian randomization (MR) studies is missing. METHODS: We used two-sample MR to examine potential causal cancer site- and sex-specific associations of the genetically-predicted allometric body-shape indices with CRC risk, and compared them with BMI-adjusted traditional body-shape indices, and BMI. Data were obtained from UK Biobank and the GIANT consortium, and from GECCO, CORECT and CCFR consortia. RESULTS: WHI was positively associated with CRC in men (OR per SD: 1.20, 95% CI: 1.03-1.39) and in women (1.15, 1.06-1.24), and similarly for colon and rectal cancer. ABSI was positively associated with colon and rectal cancer in men (1.27, 1.03-1.57; and 1.40, 1.10-1.77, respectively), and with colon cancer in women (1.20, 1.07-1.35). There was little evidence for association between HI and colon or rectal cancer. The BMI-adjusted WHR and HC showed similar associations to WHI and HI, whereas WC showed similar associations to ABSI only in women. CONCLUSIONS: This large MR study provides strong evidence for a potential causal positive association of the allometric indices ABSI and WHI with CRC in both sexes, thus establishing the association between abdominal fat and CRC without the limitations of the traditional waist size indices and independently of BMI. Among the BMI-adjusted traditional indices, WHR and HC provided equivalent associations with WHI and HI, while differences were observed between WC and ABSI.

Characterization of additive gene-environment interactions for colorectal cancer risk.

BACKGROUND: Colorectal cancer (CRC) is a common, fatal cancer. Identifying subgroups who may benefit more from intervention is of critical public health importance. Previous studies have assessed multiplicative interaction between genetic risk scores and environmental factors, but few have assessed additive interaction, the relevant public health measure. METHODS: Using resources from colorectal cancer consortia including 45,247 CRC cases and 52,671 controls, we assessed multiplicative and additive interaction (relative excess risk due to interaction, RERI) using logistic regression between 13 harmonized environmental factors and genetic risk score including 141 variants associated with CRC risk. RESULTS: There was no evidence of multiplicative interaction between environmental factors and genetic risk score. There was additive interaction where, for individuals with high genetic susceptibility, either heavy drinking [RERI = 0.24, 95% confidence interval, CI, (0.13, 0.36)], ever smoking [0.11 (0.05, 0.16)], high BMI [female 0.09 (0.05, 0.13), male 0.10 (0.05, 0.14)], or high red meat intake [highest versus lowest quartile 0.18 (0.09, 0.27)] was associated with excess CRC risk greater than that for individuals with average genetic susceptibility. Conversely, we estimate those with high genetic susceptibility may benefit more from reducing CRC risk with aspirin/NSAID use [-0.16 (-0.20, -0.11)] or higher intake of fruit, fiber, or calcium [highest quartile versus lowest quartile -0.12 (-0.18, -0.050); -0.16 (-0.23, -0.09); -0.11 (-0.18, -0.05), respectively] than those with average genetic susceptibility. CONCLUSIONS: Additive interaction is important to assess for identifying subgroups who may benefit from intervention. The subgroups identified in this study may help inform precision CRC prevention.

Symmetry Protected Two-Photon Coherence Time.

We report the observation of symmetry protected two-photon coherence time of biphotons generated from backward spontaneous four-wave mixing in laser-cooled ^{87}Rb atoms. When biphotons are nondegenerate, nonsymmetric photonic absorption loss results in exponential decay of the temporal waveform of the two-photon joint probability amplitude, leading to shortened coherence time. In contrast, in the case of degenerate biphotons, when both paired photons propagate with the same group velocity and absorption coefficient, the two-photon coherence time, protected by space-time symmetry, remains unaffected by medium absorptive losses. Our experimental results validate these theoretical predictions. This outcome highlights the pivotal role of symmetry in manipulating and controlling photonic quantum states.

Crystallization of Poly(l-lactic acid) on Water Surfaces via Controlled Solvent Evaporation and Langmuir-Blodgett Films.

Solvent evaporation is one of the most fundamental processes in soft matter. Structures formed via solvent evaporation are often complex yet tunable via the competition between solute diffusion and solvent evaporation time scales. This work concerns the polymer evaporative crystallization on the water surface (ECWS). The dynamic and two-dimensional (2D) nature of the water surface offers a unique way to control the crystallization pathway of polymeric materials. Using poly(l-lactic acid) (PLLA) as the model polymer, we demonstrate that both one-dimensional (1D) crystalline filaments and two-dimensional (2D) lamellae are formed via ECWS, in stark contrast to the 2D Langmuir-Blodgett monolayer systems as well as polymer solution crystallization. Results show that this filament-lamella biphasic structure is tunable via chemical structures such as molecular weight and processing conditions such as temperature and evaporation rate.

Relationships Among Physical Activity, Sleep, and Cancer-related Fatigue: Results From the International ColoCare Study.

BACKGROUND: Risk factors for cancer-related fatigue are understudied in colorectal cancer. PURPOSE: This study aimed to address this critical gap in the literature by (a) describing changes in colorectal cancer-related fatigue and health behavior (physical activity, sleep problems) and (b) examining if physical activity and sleep problems predict fatigue trajectories from baseline (approximately at the time of diagnosis), to 6- and 12 months after enrollment. METHODS: Patients participating in the international ColoCare Study completed self-report measures at baseline (approximately time of diagnosis), 6-, and 12 months assessing physical activity using the International Physical Activity Questionnaire (IPAQ) and fatigue and sleep using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC-QLQ-C30). Mixed-effect models examined changes in physical activity, sleep problems, and fatigue. Cross-lagged panel models examined bidirectional relationships between physical activity or sleep and fatigue across time. RESULTS: Colorectal cancer patients (n = 649) had a mean age of 61 ± 13 years. Most were male (59%), non-Hispanic White (91%), diagnosed with Stages III-IV (56%) colon cancer (58%), and treated with surgery (98%). Within-person cross-lagged models indicated higher physical activity at Month 6 was associated with higher fatigue at Month 12 (ß = 0.26, p = .016). When stratified by cancer stage (I-II vs. III-IV), the relationship between physical activity at Month 6 and fatigue at Month 12 existed only for patients with advanced cancer (Stages III and IV, ß = 0.43, p = .035). Cross-lagged associations for sleep and fatigue from baseline to Month 6 were only observed in patients with Stages III or IV cancer, however, there was a clear cross-sectional association between sleep problems and fatigue at baseline and Month 6. CONCLUSIONS: Within-person and cross-lagged association models suggest fatiguability may become increasingly problematic for patients with advanced colorectal cancer the first year after diagnosis. In addition, sleep problems were consistently associated with higher fatigue in the first year, regardless of cancer stage. TRIAL REGISTRATION: The international ColoCare Study was registered on clinicaltrials.gov, NCT02328677, in December 2014.

Within-person and cross-lagged association models suggest fatiguability may become increasingly problematic for patients with advanced (Stages III and IV) colorectal cancer the first year after diagnosis.

Functional quality of life among newly diagnosed young adult colorectal cancer survivors compared to older adults: results from the ColoCare Study.

PURPOSE: Colorectal cancer (CRC) incidence and mortality are increasing among young adults (YAs) aged 18-39. This study compared quality of life (QOL) between YA and older adult CRC survivors in the ColoCare Study. METHODS: Participants were grouped by age (years) as follows: 18-39 (YA), 40-49, 50-64, and 65 + . Functional QOL (physical, social, role, emotional, cognitive) and global QOL were assessed with the EORTC-QLQ-C30 at enrollment, 3, 6, and 12 months. Average scores were compared between groups over time using longitudinal mixed-effect modeling. Proportions with clinically meaningful QOL impairment were calculated using age-relevant thresholds and compared between groups over time using logistic regression with mixed effects. RESULTS: Participants (N = 1590) were n = 81 YAs, n = 196 aged 40-49, n = 627 aged 50-64, and n = 686 aged 65 + . Average physical function was better among YAs than participants aged 50-64 (p = 0.010) and 65 + (p < 0.001), and average social function was worse among YAs than aged 65 + (p = 0.046). Relative to YAs, all age groups were less likely to report clinically meaningful social dysfunction (aged 40-49 OR = 0.13, 95%CI = 0.06-0.29; aged 50-64 OR = 0.10, 95%CI = 0.05-0.21; aged 65 + OR = 0.07, 95%CI = 0.04-0.15) and role dysfunction (aged 40-49 OR = 0.36, 95%CI = 0.18-0.75; aged 50-64 OR = 0.41, 95%CI = 0.22-0.78; aged 65 + OR = 0.32, 95%CI = 0.17-0.61). Participants aged 40-49 were also less likely to report physical dysfunction (OR = 0.42, 95%CI = 0.19-0.93). CONCLUSION: YA CRC survivors reported better physical and worse social function compared to older CRC survivors, and YA CRC survivors were more likely to report clinically meaningful social, role, and physical disfunction. Future work should further investigate QOL using age-relevant benchmarks to inform best practices for CRC survivorship care. TRIAL REGISTRATION: NCT02328677, registered December 2014.

Risk factors and health behaviors associated with loneliness among cancer survivors during the COVID-19 pandemic.

Loneliness may exacerbate poor health outcomes particularly among cancer survivors during the COVID-19 pandemic. Little is known about the risk factors of loneliness among cancer survivors. We evaluated the risk factors of loneliness in the context of COVID-19 pandemic-related prevention behaviors and lifestyle/psychosocial factors among cancer survivors. Cancer survivors (n = 1471) seen at Huntsman Cancer Institute completed a survey between August-September 2020 evaluating health behaviors, medical care, and psychosocial factors including loneliness during COVID-19 pandemic. Participants were classified into two groups: 'lonely' (sometimes, usually, or always felt lonely in past month) and 'non-lonely' (never or rarely felt lonely in past month). 33% of cancer survivors reported feeling lonely in the past month. Multivariable logistic regression showed female sex, not living with a spouse/partner, poor health status, COVID-19 pandemic-associated lifestyle factors including increased alcohol consumption and marijuana/CBD oil use, and psychosocial stressors such as disruptions in daily life, less social interaction, and higher perceived stress and financial stress were associated with feeling lonely as compared to being non-lonely (all p < 0.05). A significant proportion of participants reported loneliness, which is a serious health risk among vulnerable populations, particularly cancer survivors. Modifiable risk factors such as unhealthy lifestyle behaviors and psychosocial stress were associated with loneliness. These results highlight the need to screen for unhealthy lifestyle factors and psychosocial stressors to identify cancer survivors at increased risk of loneliness and to develop effective management strategies.

Genome-wide Modeling of Polygenic Risk Score in Colorectal Cancer Risk.

Accurate colorectal cancer (CRC) risk prediction models are critical for identifying individuals at low and high risk of developing CRC, as they can then be offered targeted screening and interventions to address their risks of developing disease (if they are in a high-risk group) and avoid unnecessary screening and interventions (if they are in a low-risk group). As it is likely that thousands of genetic variants contribute to CRC risk, it is clinically important to investigate whether these genetic variants can be used jointly for CRC risk prediction. In this paper, we derived and compared different approaches to generating predictive polygenic risk scores (PRS) from genome-wide association studies (GWASs) including 55,105 CRC-affected case subjects and 65,079 control subjects of European ancestry. We built the PRS in three ways, using (1) 140 previously identified and validated CRC loci; (2) SNP selection based on linkage disequilibrium (LD) clumping followed by machine-learning approaches; and (3) LDpred, a Bayesian approach for genome-wide risk prediction. We tested the PRS in an independent cohort of 101,987 individuals with 1,699 CRC-affected case subjects. The discriminatory accuracy, calculated by the age- and sex-adjusted area under the receiver operating characteristics curve (AUC), was highest for the LDpred-derived PRS (AUC = 0.654) including nearly 1.2 M genetic variants (the proportion of causal genetic variants for CRC assumed to be 0.003), whereas the PRS of the 140 known variants identified from GWASs had the lowest AUC (AUC = 0.629). Based on the LDpred-derived PRS, we are able to identify 30% of individuals without a family history as having risk for CRC similar to those with a family history of CRC, whereas the PRS based on known GWAS variants identified only top 10% as having a similar relative risk. About 90% of these individuals have no family history and would have been considered average risk under current screening guidelines, but might benefit from earlier screening. The developed PRS offers a way for risk-stratified CRC screening and other targeted interventions.

Prospective and Mendelian randomization analyses on the association of circulating fatty acid binding protein 4 (FABP-4) and risk of colorectal cancer.

BACKGROUND: Fatty acid binding protein 4 (FABP-4) is a lipid-binding adipokine upregulated in obesity, which may facilitate fatty acid supply for tumor growth and promote insulin resistance and inflammation and may thus play a role in colorectal cancer (CRC) development. We aimed to investigate the association between circulating FABP-4 and CRC and to assess potential causality using a Mendelian randomization (MR) approach. METHODS: The association between pre-diagnostic plasma measurements of FABP-4 and CRC risk was investigated in a nested case-control study in 1324 CRC cases and the same number of matched controls within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. A two-sample Mendelian randomization study was conducted based on three genetic variants (1 cis, 2 trans) associated with circulating FABP-4 identified in a published genome-wide association study (discovery n = 20,436) and data from 58,131 CRC cases and 67,347 controls in the Genetics and Epidemiology of Colorectal Cancer Consortium, Colorectal Cancer Transdisciplinary Study, and Colon Cancer Family Registry. RESULTS: In conditional logistic regression models adjusted for potential confounders including body size, the estimated relative risk, RR (95% confidence interval, CI) per one standard deviation, SD (8.9 ng/mL) higher FABP-4 concentration was 1.01 (0.92, 1.12) overall, 0.95 (0.80, 1.13) in men and 1.09 (0.95, 1.25) in women. Genetically determined higher FABP-4 was not associated with colorectal cancer risk (RR per FABP-4 SD was 1.10 (0.95, 1.27) overall, 1.03 (0.84, 1.26) in men and 1.21 (0.98, 1.48) in women). However, in a cis-MR approach, a statistically significant association was observed in women (RR 1.56, 1.09, 2.23) but not overall (RR 1.23, 0.97, 1.57) or in men (0.99, 0.71, 1.37). CONCLUSIONS: Taken together, these analyses provide no support for a causal role of circulating FABP-4 in the development of CRC, although the cis-MR provides some evidence for a positive association in women, which may deserve to be investigated further.

Lessons to inform interventions to reduce racial and ethnic health disparities within hematologic malignancies.

Although racial and ethnic disparities in diagnosis, treatment, and survival have been well documented within the field of hematologic malignancies, very little work has focused on testing interventions that may reduce these disparities. The aim of this commentary is to review prior work in hematologic malignancies and explore new opportunities to develop disparity-reducing interventions by drawing from evidence-based strategies that have been successfully implemented in fields related to hematologic malignancies, including oncology and solid organ transplants. Relevant literature demonstrates that patient navigation and broader insurance coverage have been shown to reduce racial and ethnic disparities among patients with solid malignancies such as colorectal and breast cancer. Evidence-based strategies that might be most applicable to the field of hematologic malignancies include patient navigation and policy changes.

Theoretical understanding of evolutionary dynamics on inhomogeneous networks.

Evolution is the main feature of all biological systems that allows populations to change their characteristics over successive generations. A powerful approach to understand evolutionary dynamics is to investigate fixation probabilities and fixation times of novel mutations on networks that mimic biological populations. It is now well established that the structure of such networks can have dramatic effects on evolutionary dynamics. In particular, there are population structures that might amplify the fixation probabilities while simultaneously delaying the fixation events. However, the microscopic origins of such complex evolutionary dynamics remain not well understood. We present here a theoretical investigation of the microscopic mechanisms of mutation fixation processes on inhomogeneous networks. It views evolutionary dynamics as a set of stochastic transitions between discrete states specified by different numbers of mutated cells. By specifically considering star networks, we obtain a comprehensive description of evolutionary dynamics. Our approach allows us to employ physics-inspired free-energy landscape arguments to explain the observed trends in fixation times and fixation probabilities, providing a better microscopic understanding of evolutionary dynamics in complex systems.

Evaluation and management of drug-eluting stent in-stent restenosis.

PURPOSE OF REVIEW: In-stent restenosis (ISR) is the most common cause of stent failure. Although the rate of ISR is significantly lower with contemporary drug-eluting stents (DES), it remains a challenging clinical entity to treat. RECENT FINDINGS: In this review, we focus on a practical approach to management of DES ISR with intravascular imaging at its core, as supported by several recently published articles. This facilitates assessment of the underlying mechanism(s) essential to the successful treatment of ISR allowing for a tailored selection of treatment modalities. SUMMARY: The successful treatment of DES ISR requires identification of the causative mechanism(s). Individualized treatment may include high-pressure balloon angioplasty alone, cutting or scoring balloons, intravascular lithotripsy, atheroablative therapies and a selection of either repeat DES implantation or drug-coated balloon treatment.

Associations of combined physical activity and body mass index groups with colorectal cancer survival outcomes.

BACKGROUND: Physical activity and BMI have been individually associated with cancer survivorship but have not yet been studied in combinations in colorectal cancer patients. Here, we investigate individual and combined associations of physical activity and BMI groups with colorectal cancer survival outcomes. METHODS: Self-reported physical activity levels (MET hrs/wk) were assessed using an adapted version of the International Physical Activity Questionnaire (IPAQ) at baseline in 931 patients with stage I-III colorectal cancer and classified into 'highly active' and'not-highly active'(≥ / < 18 MET hrs/wk). BMI (kg/m2) was categorized into 'normal weight', 'overweight', and 'obese'. Patients were further classified into combined physical activity and BMI groups. Cox-proportional hazard models with Firth correction were computed to assess associations [hazard ratio (HR), 95% profile HR likelihood confidence interval (95% CI) between individual and combined physical activity and BMI groups with overall and disease-free survival in colorectal cancer patients. RESULTS: 'Not-highly active' compared to 'highly active' and 'overweight'/ 'obese' compared to 'normal weight' patients had a 40-50% increased risk of death or recurrence (HR: 1.41 (95% CI: 0.99-2.06), p = 0.03; HR: 1.49 (95% CI: 1.02-2.21) and HR: 1.51 (95% CI: 1.02-2.26), p = 0.04, respectively). 'Not-highly active' patients had worse disease-free survival outcomes, regardless of their BMI, compared to 'highly active/normal weight' patients. 'Not-highly active/obese' patients had a 3.66 times increased risk of death or recurrence compared to 'highly active/normal weight' patients (HR: 4.66 (95% CI: 1.75-9.10), p = 0.002). Lower activity thresholds yielded smaller effect sizes. CONCLUSION: Physical activity and BMI were individually associated with disease-free survival among colorectal cancer patients. Physical activity seems to improve survival outcomes in patients regardless of their BMI.

Poly (3-hexylthiophene) (P3HT) Crystalsomes: Tiling 1D Polymer Crystals on a Spherical Surface.

Polymer crystalsomes are a class of hollow crystalline polymer nanoparticles with shells formed by single crystals with broken translational symmetry. They have shown intriguing mechanical, thermal, and biomedical properties associated with spherical packing. Previously reported crystalsomes are formed by quasi-2D lamellae which can readily tile on a spherical surface. In this work, the formation of polymer crystalsomes formed by 1D polymer crystals is reported. Poly (3-hexylthiophene) (P3HT) is chosen as the model polymer because of its 1D growth habit. P3HT crystalsomes are successfully fabricated using a miniemulsion solution crystallization method, as confirmed by scanning electron microscopy and transmission electron microscopy. X-ray diffraction (XRD) and selected area electron diffraction experiments confirm that P3HT crystallized into a Form I crystal structure. XRD, differential scanning calorimetry and UV-Vis results reveal curvature-dependent structural, thermal and electro-optical properties.

Fabrication of Surface Polymer Brushes Via Thin Film Crystallization and Solvent Annealing.

Polymer single crystals are used as templates to synthesize polymer brushes, known as the "polymer-single-crystal-assisted-grafting-to" (PSCAGT) approach. Polymer brushes with controlled grafting densities and spatial tethering locations are demonstrated. Previous works focused on solution crystallization, which involves large amounts of organic solvent, and the grafting density can only be tuned by varying crystallization temperatures. In this work, thin film crystallization is utilized to fabricate 2D polymer crystals on flat surfaces. Subsequent chemical tethering leads to polymer brushes that retain the original morphology of the crystals with high fidelity. Furthermore, it is shown that the grafting density of the polymer brushes fabricated using this method depends on the chain end distribution on the top/bottom surfaces of the crystal, which can be facilely controlled by annealing the crystals at various nonsolvent media. This work broadens the scope of the PSCAGT method and provides a new route to achieve polymer brushes with controlled structures.

Trajectories and risk factors of fatigue following colorectal cancer diagnosis.

AIM: This study sought to identify groups of colorectal cancer patients based upon trajectories of fatigue and examine how demographic, clinical and behavioural risk factors differentiate these groups. METHOD: Patients were from six cancer centres in the United States and Germany. Fatigue was measured using the fatigue subscale of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30) at five time points (baseline/enrolment and 3, 6, 12 and 24 months after diagnosis). Piecewise growth mixture models identified latent trajectories of fatigue. Logistic regression models examined differences in demographic, clinical and behavioural characteristics between fatigue trajectory groups. RESULTS: Among 1615 participants (57% men, 86% non-Hispanic White, mean age 61 ± 13 years at diagnosis), three distinct groups were identified. In the high fatigue group (36%), fatigue significantly increased in the first 6 months after diagnosis and then showed statistically and clinically significant improvement from 6 to 24 months (P values < 0.01). Throughout the study period, average fatigue met or exceeded cutoffs for clinical significance. In the moderate (34%) and low (30%) fatigue groups, fatigue levels remained below or near population norms across the study period. Patients who were diagnosed with Stage II-IV disease and/or current smokers were more likely to be in the high fatigue than in the moderate fatigue group (P values < 0.05). CONCLUSION: A large proportion of colorectal cancer patients experienced sustained fatigue after initiation of cancer treatment. Patients with high fatigue at the time of diagnosis may benefit from early supportive care.