We studied the prognostic value of primary tumor sidedness in metastatic colorectal cancer over time and across treatment lines. Population data on synchronous metastatic colorectal cancer patients ...were extracted from the Netherlands Cancer Registry and SEER database. Pubmed, EMBASE and Cochrane library were searched for prospective studies on metastatic colorectal cancer to conduct a meta‐analysis. Inclusion criteria consisted of metastatic disease, systemic treatment with palliative intent and specification of primary tumor location. Data were pooled using a random‐effects model. For the population‐based data, multivariable Cox models were constructed. The Grambsch‐Therneau test was conducted to evaluate the potential time‐varying nature of sidedness. Meta‐regression incorporating treatment‐line as variable was conducted to test the pre‐specified hypothesis that the prognostic value of sidedness varies over time. Analysis of 12 885 and 16 160 synchronous metastatic colorectal cancer patients registered in the Netherlands Cancer Registry and SEER database, respectively, indicated a time‐varying prognostic value of sidedness (P < .01). Thirty‐one studies were selected for the meta‐analysis (9558 patients for overall survival analysis). Pooled univariable hazard ratioleft‐sided/right‐sided for overall survival was 0.71 (95% CI: 0.65‐0.76) in 1st‐line, 0.76 (0.54‐1.06) in 2nd‐line and 1.01 (0.86‐1.19) in 3rd‐line studies. Hazard ratios were significantly influenced by treatment line (P = .035). The prognostic value of sidedness of the primary tumor in metastatic colorectal cancer patients treated with palliative systemic therapy decreases over time since diagnosis, suggesting that sidedness may not be a useful stratification factor in late‐line trials. This decrease in prognostic value should be taken into account when providing prognostic information to patients.
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In colorectal cancer (CRC), sidedness is linked to prognosis, with left‐sided primary tumors associated with improved prognosis compared to right‐sided tumors. These associations suggest that sidedness is a potential stratification factor in clinical trials. Here, the authors analyzed published literature and population‐based registries to gain insight on the prognostic value of sidedness in metastatic CRC. Data show that, among metastatic CRC patients treated with palliative therapy, the prognostic utility of sidedness declines over time. Hence, CRC sidedness likely has little value as a stratification factor for clinical trials but may assist clinicians in providing prognostic information to metastatic CRC patients.
Multidrug resistance (MDR) remains a major obstacle to successful chemotherapeutic treatment of cancer and can be caused by
overexpression of P-glycoprotein, the MDR1 gene product. To further ...validate a knockdown approach for circumventing MDR, we developed a P-glycoprotein inhibition strategy
using short hairpin RNA interference (shRNAi) and now show efficacy and target specificity in vivo . Two of eight tested shRNAi constructs targeted against human MDR1 mRNA inhibited expression of P-glycoprotein by >90%, whereas control shRNAi had no effect. Ablation of P-glycoprotein in
cells stably transduced with retroviral-mediated shRNAi was documented by Western blot and functionally confirmed by increased
sensitivity of MDR1 -transfected cells toward the cytotoxic drugs vincristine, paclitaxel, and doxorubicin as well as by transport of 99m Tc-Sestamibi. shRNAi-mediated down-regulation of P-glycoprotein transport activity both in cultured cells and in tumor implants
in living animals could be followed by direct noninvasive bioluminescence imaging using the Renilla luciferase fluorophore, coelenterazine, a known P-glycoprotein transport substrate. Furthermore, after somatic gene transfer
by hydrodynamic infusion of a MDR1-Firefly luciferase ( MDR1-FLuc ) fusion construct into mouse liver, the effect of shRNAi delivered in vivo on P-glycoprotein-FLuc protein levels was documented with bioluminescence imaging using d -luciferin. ShRNAi against MDR1 reduced bioluminescence output of the P-glycoprotein-FLuc reporter 4-fold in vivo compared with mice treated with control or scrambled shRNAi. Targeted down-regulation of a somatically transferred P-glycoprotein-eGFP
fusion reporter also was observed using fluorescence microscopy. Our results show that shRNAi effectively inhibited MDR1 expression and function in cultured cells, tumor implants and mammalian liver, documenting the feasibility of a knockdown
approach to reversing MDR in vivo .
Mercaptopurines have been used as anticancer agents for more than 40 years, and most acute lymphoblastic leukemias are treated
with 6-mercaptopurine (6MP) or 6-thioguanine (TG). Overexpression of the ...two related multidrug resistance proteins MRP4 and
MRP5 has been shown to confer some resistance against mercaptopurines, which has been attributed to extrusion of mercaptopurine
metabolites by these transporters. We have analyzed the mercaptopurine metabolites formed in human embryonic kidney cells
and determined which metabolites are extruded by MRP4 and MRP5. Incubation with 6MP led to the formation of thioinosine and
thioxanthosine metabolites and we found that thio-IMP was transported by both MRP4 and MRP5; MRP5 showed the highest transport
rate. In contrast, only MRP5 transported thioxanthosine monophosphate (tXMP). During incubation with TG, the monophosphorylated
form of thioguanosine was transported by both MRP4 and MRP5; the highest transport rate was for MRP4. Similarly, only 6-methyl-thio-IMP
was formed during incubation with 6-methyl mercaptopurine riboside. This compound was a substrate for both MRP4 and MRP5;
MRP4 showed the highest transport rate. Our results show that all major thiopurine monophosphates important in the efficacy
of mercaptopurine treatment are transported by MRP4 and MRP5, although the substrate specificity of the two transporters differs
in detail.
Inulin is a soluble dietary fibre, also classified as a prebiotic, extracted from chicory roots. The present study aimed to determine the effect of consumption of native chicory inulin on the stool ...frequency of middle-aged to older adults (40–75 years old) with uncomfortably but not clinically relevant low stool frequency, specified as two to four days without bowel movements per week. Two randomised, double blind, placebo-controlled crossover trials were conducted using similar protocols in differing populations. Trial A was conducted in Amsterdam, The Netherlands and subsequently Trial B was conducted in Newcastle, United Kingdom. Both trials involved supplementation for 5 weeks with 10 g per day of inulin or placebo, a washout period of 2 weeks, and then crossed over to receive the other treatment. In Trial B, faecal gut microbiota composition was assessed using 16S rRNA gene sequencing. In Trial A, which 10 volunteers completed, the stool frequency was significantly increased to an average 4.9 ± 0.23 (SEM) times per week during inulin periods versus 3.6 ± 0.25 in the periods with placebo (p = 0.01). In contrast, in Trial B which 20 volunteers completed, there was no significant effect of the inulin on stool frequency (7.5 ± 2.1 times per week with inulin, 8.1 ± 3.0 with placebo, p = 0.35). However, many subjects in Trial B had a stool frequency >5 per week also for the placebo period, in breach of the inclusion criteria. Combining the data of 16 low stool frequency subjects from Trials A and B showed a significant effect of inulin to increase stool frequency from 4.1 to 5.0 per week (p = 0.032). Regarding secondary outcomes, stool consistency was significantly softer with inulin treatment compared to placebo periods, it increased 0.29 on the Bristol stool scale (p = 0.008) when data from all subjects of Trials A and B were combined. No other differences in bowel habit parameters due to inulin consumption were significant. None of the differences in specific bacterial abundance, alpha or beta diversity were significant, however the trends were in directions consistent with published studies on other types of inulin. We conclude that 10 g per day of native chicory inulin can increase stool frequency in subjects with low stool frequency.
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•Inulin as 10g day-1 for 5 weeks significantly increased stool frequency in 16 older volunteers compared with maltodextrin..•This increase was found in volunteers with low stool frequency (2 days or more per week without bowel movements).•Directions of changes in secondary outcomes were generally consistent with expectations for prebiotic effects of inulin.•Secondary outcomes included quality of life symptoms, stool consistency and composition of the faecal microbiota.•Among secondary outcomes, only softening of stool consistency reached significance within the present study.
Chronic low-grade inflammatory profile (CLIP) is one of the pathways involved in type 2 diabetes (T2D). Currently, there is limited evidence for ameliorating effects of combined lifestyle ...interventions on CLIP in type 2 diabetes. We investigated whether a 13-week combined lifestyle intervention, using hypocaloric diet and resistance exercise plus high-intensity interval training with or without consumption of a protein drink, affected CLIP in older adults with T2D.
In this post-hoc analysis of the PROBE study 114 adults (≥55 years) with obesity and type 2 (pre-)diabetes had measurements of C-reactive protein (CRP), pro-inflammatory cytokines interleukin (IL)-6, tumor-necrosis-factor (TNF)-α, and monocyte chemoattractant protein (MCP)-1, anti-inflammatory cytokines IL-10, IL-1 receptor antagonist (RA), and soluble tumor-necrosis-factor receptor (sTNFR)1, adipokines leptin and adiponectin, and glycation biomarkers carboxymethyl-lysine (CML) and soluble receptor for advanced glycation end products (sRAGE) from fasting blood samples. A linear mixed model was used to evaluate change in inflammatory biomarkers after lifestyle intervention and effect of the protein drink. Linear regression analysis was performed with parameters of body composition (by dual-energy X-ray absorptiometry) and parameters of insulin resistance (by oral glucose tolerance test).
There were no significant differences in CLIP responses between the protein and the control groups. For all participants combined, IL-1RA, leptin and adiponectin decreased after 13 weeks (p = 0.002, p < 0.001 and p < 0.001), while ratios TNF-α/IL-10 and TNF-α/IL-1RA increased (p = 0.003 and p = 0.035). CRP increased by 12 % in participants with low to average CLIP (pre 1.91 ± 0.39 mg/L, post 2.13 ± 1.16 mg/L, p = 0.006) and decreased by 36 % in those with high CLIP (pre 5.14 mg/L ± 1.20, post 3.30 ± 2.29 mg/L, p < 0.001). Change in leptin and IL-1RA was positively associated with change in fat mass (β = 0.133, p < 0.001; β = 0.017, p < 0.001) and insulin resistance (β = 0.095, p = 0.024; β = 0.020, p = 0.001). Change in lean mass was not associated with any of the biomarkers.
13 weeks of combined lifestyle intervention, either with or without protein drink, reduced circulating adipokines and anti-inflammatory cytokine IL-1RA, and increased inflammatory ratios TNF-α/IL-10 and TNF-α/IL-1RA in older adults with obesity and T2D. Effect on CLIP was inversely related to baseline inflammatory status.
•Chronic low-grade inflammatory profile (CLIP) is common in type 2 diabetes (T2D).•We tested lifestyle + protein intervention effect on CLIP in 114 older T2D patients.•IL-1RA and adipokines decreased while TNF-α/IL-10 and TNF-α/IL-1RA ratios increased.•Effect on CLIP was inversely related to baseline inflammatory status.•Additional lean mass gain due to protein supplementation was not affected by CLIP.
Far-red dyes such as cyanine 5 (Cy5) are gaining interest in (bio)medical diagnostics as they have promising features in terms of stability and brightness. Here, the electrostatic density and ...stacking tendency in different solvents of nine systematically altered asymmetrical Cy5 dyes are reported. In addition to this, the influence of molecular alterations on the vibronic coupling was reported. The data presented supplement to the recent study “The influence of systematic structure alterations on the photophysical properties and conjugation characteristics of asymmetric cyanine 5 dyes” (Spa et al., 2018).
Location of the primary tumor has prognostic value and predicts the effect of certain therapeutics in synchronous metastatic colorectal cancer. We investigated whether the association between primary ...tumor resection (PTR) and overall survival (OS) also depends on tumor location.
Data on synchronous metastatic colorectal cancer patients from the Netherlands Cancer Registry (n=16,106) and Surveillance, Epidemiology, and End Results (SEER) registry (n=19,584) were extracted. Cox models using time-varying covariates were implemented. Median OS for right-sided colon cancer (RCC), left-sided colon cancer, and rectal cancer was calculated using inverse probability weighting and a landmark point of 6 months after diagnosis as reference.
The association between PTR and OS was dependent on tumor location (P<0.05), with a higher median OS of upfront PTR versus upfront systemic therapy in Netherlands Cancer Registry (NCR) of 1.9 (95% confidence interval: 0.9-2.8), 4.3 (3.3-5.6), and 3.4 (0.6-7.6) months in RCC, left-sided colon cancer and rectal cancer, respectively. In SEER data, the difference was 6.0 (4.0-8.0), 8.0 (5.0-10.0), and 10.0 (7.0-13.0) months, respectively. Hazard plots indicate a higher hazard of death 2 to 3 months after PTR in RCC.
Upfront PTR is associated with improved survival regardless of primary tumor location. Patients with RCC appear to have less benefit because of higher mortality during 2 to 3 months after PTR.
The light spectrum above 650 nm allows for good tissue penetration depths, therefore far-red and near-infrared fluorescent dyes are popular fluorophores applied in (bio)medical diagnostics, including ...image-guided surgery. Unfortunately, near-infrared fluorescent dyes often suffer from instability and limited brightness, two important features that, together with the labelling efficiency (e.g., non- one- or di-conjugated products) and serum-dye interactions are key elements that drive in vivo characteristics. Due to the fact that stability and brightness of far-red fluorophores are often superior over near-infrared dyes, interest in the use of dyes such as Cy5 is increasing. As there are clear indications that the chemical structure of a dye influences the (photo)physical properties, these properties of ten structural variants of asymmetrical Cy5-(R1)R2-(R3)COOH (R representing the varied substituents) dyes were extensively studied. While stacking in solution was not induced in most of the Cy5 far-red dyes, multimers and stacking characteristics were observed in protein conjugates. Although all dye variants were shown to be stable towards photobleaching, clear differences in brightness and serum interactions were found. Combined, these findings indicate that there is a direct relation between chemical substituents and the properties of Cy5 dyes, and that this feature should be considered when using fluorescent dyes in future tracer development.
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•Clear differences in brightness were found upon changing the fluorophore substituents.•The investigated fluorophores were optical and chemically stable.•Increasing number of sulfonates on the Cy5 decreased non-specific serum protein interactions.•Clear differences in labelling efficiencies between the dyes were found during protein conjugation.
A series of nine luminescent cyclometalated octahedral iridium(III) tris(2-phenylpyridine) complexes has been synthesized, functionalized with three different amino acids (glycine, alanine, and ...lysine), on one, two, or all three of the phenylpyridine ligands. All starting complexes and final compounds have been fully analyzed by one-dimensional (1D) and two-dimensional (2D) NMR spectroscopy, and photophysical data have been obtained for all the mono-, bis-, and tri- substituted iridium(III) complexes. Cellular uptake and localization have been studied with flow cytometry and confocal microscopy, respectively. Confocal experiments demonstrate that all nine substituted iridium(III) complexes show variable uptake in the tumor cells. The monosubstituted iridium(III) complexes give the highest cellular uptake, and the series substituted with lysines shows the highest toxicity. This systematic study of amino acid-functionalized Ir(ppy)3 complexes provides guidelines for further functionalization and possible implementation of luminescent iridium complexes, for example, in (automated) peptide synthesis or biomarker specific targeting.
The projections from the Ammon's horn to the cholinergic cell groups in the medial septal and diagonal band nuclei were investigated with anterograde tracing of Phaseolus vulgaris leucoagglutinin ...combined with immunocytochemical detection of choline acetyltransferase, in the rat. Tracer injections were placed into various fields of the septal and temporal parts of the Ammon's horn (CA1-3). These injections revealed differential distributions of Phaseolus vulgaris leucoagglutinin-labeled projections in both the lateral septal area and the medial septum-diagonal band complex. In addition to the labeling of dense axonal networks in the lateral septal area, significant numbers of arborizing fibers were labeled in the medial septal and diagonal band nuclei, in particular after tracer injections into the fields CA2-3. The distributions of the projections to the medial septum-diagonal band complex arising from the septal portion of fields CA1 and CA2-3 are similar. In contrast, the septal part and temporal portion of field CA3 project in a topographically differentiated manner to the medial septum and nuclei of the diagonal band. The septal pole of the Ammon's horn innervates the dorsal and medial parts of the medial septal nucleus and the anterior and dorsal parts of the vertical limb of the diagonal band. Axons of the temporal pole of the hippocampus reach the lateral and ventral parts of the medial septum and the intermediate, caudal and ventral parts of the vertical limb of the diagonal band. These results demonstrate direct feedback projections of the Ammon's horn to the medial septum-diagonal band complex, which show a topographic organization mainly as a function of the septotemporal level of the hippocampus. Within the medial septal and diagonal band nuclei, the labeled varicosities are formed in close proximity to the cell bodies and dendrites of the cholinergic neurons.