Lipid-polymer hybrid nanoparticles (LPHNPs) are next-generation core-shell nanostructures, conceptually derived from both liposome and polymeric nanoparticles (NPs), where a polymer core remains ...enveloped by a lipid layer. Although they have garnered significant interest, they remain not yet widely exploited or ubiquitous. Recently, a fundamental transformation has occurred in the preparation of LPHNPs, characterized by a transition from a two-step to a one-step strategy, involving synchronous self-assembly of polymers and lipids. Owing to its two-in-one structure, this approach is of particular interest as a combinatorial drug delivery platform in oncology. In particular, the outer surface can be decorated in multifarious ways for active targeting of anticancer therapy, delivery of DNA or RNA materials, and use as a diagnostic imaging agent. This review will provide an update on recent key advancements in design, synthesis, and bioactivity evaluation as well as discussion of future clinical possibilities of LPHNPs.
Recently identified molecular subgroups of medulloblastoma have shown potential for improved risk stratification. We hypothesized that distinct MR imaging features can predict these subgroups.
All ...patients with a diagnosis of medulloblastoma at one institution, with both pretherapy MR imaging and surgical tissue, served as the discovery cohort (n = 47). MR imaging features were assessed by 3 blinded neuroradiologists. NanoString-based assay of tumor tissues was conducted to classify the tumors into the 4 established molecular subgroups (wingless, sonic hedgehog, group 3, and group 4). A second pediatric medulloblastoma cohort (n = 52) from an independent institution was used for validation of the MR imaging features predictive of the molecular subtypes.
Logistic regression analysis within the discovery cohort revealed tumor location (P < .001) and enhancement pattern (P = .001) to be significant predictors of medulloblastoma subgroups. Stereospecific computational analyses confirmed that group 3 and 4 tumors predominated within the midline fourth ventricle (100%, P = .007), wingless tumors were localized to the cerebellar peduncle/cerebellopontine angle cistern with a positive predictive value of 100% (95% CI, 30%-100%), and sonic hedgehog tumors arose in the cerebellar hemispheres with a positive predictive value of 100% (95% CI, 59%-100%). Midline group 4 tumors presented with minimal/no enhancement with a positive predictive value of 91% (95% CI, 59%-98%). When we used the MR imaging feature-based regression model, 66% of medulloblastomas were correctly predicted in the discovery cohort, and 65%, in the validation cohort.
Tumor location and enhancement pattern were predictive of molecular subgroups of pediatric medulloblastoma and may potentially serve as a surrogate for genomic testing.
Tumor location has been shown to be a significant prognostic factor in patients with glioblastoma. The purpose of this study was to characterize glioblastoma lesions by identifying MR imaging ...voxel-based tumor location features that are associated with tumor molecular profiles, patient characteristics, and clinical outcomes.
Preoperative T1 anatomic MR images of 384 patients with glioblastomas were obtained from 2 independent cohorts (n = 253 from the Stanford University Medical Center for training and n = 131 from The Cancer Genome Atlas for validation). An automated computational image-analysis pipeline was developed to determine the anatomic locations of tumor in each patient. Voxel-based differences in tumor location between good (overall survival of >17 months) and poor (overall survival of <11 months) survival groups identified in the training cohort were used to classify patients in The Cancer Genome Atlas cohort into 2 brain-location groups, for which clinical features, messenger RNA expression, and copy number changes were compared to elucidate the biologic basis of tumors located in different brain regions.
Tumors in the right occipitotemporal periventricular white matter were significantly associated with poor survival in both training and test cohorts (both, log-rank P < .05) and had larger tumor volume compared with tumors in other locations. Tumors in the right periatrial location were associated with hypoxia pathway enrichment and PDGFRA amplification, making them potential targets for subgroup-specific therapies.
Voxel-based location in glioblastoma is associated with patient outcome and may have a potential role for guiding personalized treatment.
We recently reported that the GG genotype of the interleukin‐6 (IL‐6)–174G>C promoter polymorphism is associated with clinical presentation of intracranial hemorrhage in brain arteriovenous ...malformation (AVM) patients. In this study, we investigated whether tissue IL‐6 expression was associated with IL‐6–174G>C genotype, and whether IL‐6 was linked to downstream targets involved in angiogenesis and vascular instability. Our results showed that the highest IL‐6 protein levels in brain AVM tissue were associated with IL‐6–174GG genotype (GG: 57.7 ± 20.2; GC: 35.6 ± 26.6; CC: 13.9 ± 10.2pg/mg; p = 0.001). IL‐6 protein levels were increased in AVM tissue from patients with hemorrhagic presentation compared with patients without hemorrhage (55 ± 22 vs 40 ± 27pg/mg; p = 0.038). IL‐6 messenger RNA expression strongly correlated with messenger RNA levels of IL‐1β, tumor necrosis factor‐α, IL‐8, matrix metalloproteinase‐3 (MMP‐3), MMP‐9, and MMP‐12. We further investigated the plausibility of IL‐6 being an upstream cytokine responsible for initiating the angiogenic cascade by cell culture and animal experiments. IL‐6 induced MMP‐3 and MMP‐9 expression and activity in mouse brain and increased proliferation and migration of cerebral endothelial cells. Together, our results suggest that the IL‐6 genotype associated with intracranial hemorrhage modulates IL‐6 expression in brain AVM tissue, which is consistent with the hypothesis that inflammatory processes induce angiogenic activity possibly contributory to brain AVM intracranial hemorrhage. Ann Neurol 2005
Accurate estimates for risk and rates of intracranial hemorrhage (ICH) in the natural course of patients harboring brain arteriovenous malformation (BAVM) are needed to provide a quantitative basis ...for planning clinical trials to evaluate interventional strategies and to help guide practice management.
We identified patients with BAVM at the Kaiser Permanente Northern California health maintenance organization and documented their clinical course. The influences of age at diagnosis, gender, race-ethnicity, ICH at presentation, venous draining pattern, and BAVM size on ICH subsequent to presentation were studied using the multivariate Cox proportional hazards model and Kaplan-Meier curves.
We identified 790 patients with BAVM (51% female; 63% white; mean age+/-SD at diagnosis: 38+/-19 years) between 1961 and 2001. Patients who presented with ICH experienced a higher rate of subsequent ICH than those who presented without ICH under multivariate analysis (hazard ratio, 3.6; 95% CI, 1.1 to 11.9; P<0.032). The effect was similar across race-ethnicity and gender. This difference in ICH rates was greatest in the first year (7% versus 3% per year) and converged over time. The effect of subsequent ICH on functional status was similar to that of the initial ICH.
Presentation with ICH was the most important predictor of future ICH, confirming previous studies. Future ICH had similar impact on functional outcome as incident ICH. Intervention to prevent ICH would be of potentially greater benefit to patients presenting with ICH, although the advantage decreases over time.
We hypothesized that patients with unruptured arteriovenous malformations (AVMs) at presentation have an increased risk of deterioration compared with patients with ruptured AVMs.
A consecutive ...series of 224 patients treated microsurgically by a single neurosurgeon during a period of 6.4 years was analyzed. Initial hemorrhagic presentation was the primary predictor variable. Neurological outcomes were assessed by use of the Modified Rankin Scale (MRS) and Glasgow Outcome Scale (GOS), and logistic regression identified predictors of deterioration at follow-up (mean duration, 1.3 yr) relative to baseline before any intervention.
Overall, 120 patients (54%) presented with hemorrhage, and all 224 patients underwent microsurgical resection. Complete resection was achieved in 220 patients (98%). According to GOS score, 13 patients (5.8%) deteriorated; according to MRS score, 45 patients (20.1%) deteriorated. Fifteen patients (6.7%) died. Hemorrhagic presentation was associated with improved outcomes, with a mean change in MRS score of +0.89 in patients with ruptured AVMs and -0.38 in patients with unruptured AVMs (P < 0.001). The final mean MRS scores in patients with unruptured AVMs were better than those in patients with ruptured AVMs (1.44 versus 1.90; P = 0.048). Presentation with an unruptured AVM was a predictor of worsening MRS score (odds ratio, 2.33; 95% confidence interval, 1.3-4.3; P = 0.006) but not of worsening GOS score.
Presentation with AVM hemorrhage is an underappreciated predictor of outcome after therapy that includes microsurgical resection. Patients with ruptured AVMs tended to have deficits at presentation and generally improved after surgery, whereas patients with unruptured AVMs tended to have normal or nearly normal neurological function at presentation and were susceptible to worsening, albeit slight, as measured by MRS scores. Sensitive outcome measures such as MRS detect subtle symptoms and impairments missed by coarser measures such as GOS. Patients should be counseled that the risks associated with elective resection of unruptured AVMs may be higher than recognized previously. Hemorrhagic brain injury and its secondary effects may mask this surgical morbidity.
Children with brain arteriovenous malformations (BAVMs) are said to be at higher risk for intracranial hemorrhage (ICH) than adults. Although this notion affects treatment decisions, the evidence to ...support this claim is limited.
To compare the risk of ICH in children versus adults with BAVM, we studied all cases of BAVM evaluated at the University of California, San Francisco (January 2000 to December 2004; n=400) and Kaiser Permanente Northern California (January 1993 to December 2004; n=819). In Kaplan-Meier survival analyses, the index date was the date of initial BAVM detection; cases were censored at time of subsequent ICH (the primary outcome, defined as ICH after initial presentation), first BAVM treatment, or loss to follow-up. Cox proportional hazards models included childhood presentation (<20 years old), hemorrhagic presentation, and other potential confounders.
Our study included 996 person-years of follow-up in the childhood presentation group and 3260 in the adult presentation group. In the unadjusted survival analysis, the subsequent ICH rates were similar for the 2 age groups (average annual rate 2.0% for children; 2.2% for adults; P=0.82 by log-rank test). BAVMs in childhood were more likely to present initially with ICH (P<0.001). After adjustment for presentation in the multivariate model, subsequent ICH rates were lower in children (hazard ratio, 0.10; 95% CI, 0.01 to 0.86; P=0.036).
Children with BAVMs do not appear to be at increased risk for a subsequent ICH compared with adults, and may even be relatively protected. Confounding by hemorrhagic presentation should be considered in any study comparing BAVM hemorrhage rates in children versus adults.
Accurate estimates of intracranial hemorrhage (ICH) risk in patients harboring brain arteriovenous malformation (BAVM) are needed to evaluate interventional strategies and to help guide clinical ...management. Identification of genetic polymorphisms associated with ICH would facilitate risk stratification in BAVM patients.
We identified patients with BAVM and documented clinical presentation, demographic data, venous drainage pattern, and BAVM size. Patients were genotyped for 5 polymorphisms in 3 inflammatory cytokine genes, and 9 polymorphisms in 5 angiogenesis-related genes. Association of genotype with risk of hemorrhagic BAVM presentation was evaluated using logistic regression analysis.
We genotyped 180 patients with BAVM (53% female, 57% white, mean age at diagnosis 35+/-17 years, 41% presenting with ICH). BAVM patients homozygous for the interleukin 6 (IL6)-174G allele had a greater risk of ICH presentation (OR, 2.62, P=0.003) than IL6-174C carriers. In a multivariate logistic regression model, IL6-174G>C genotype, small BAVM size, and exclusively deep venous drainage were independent predictors of ICH presentation. A similar univariate trend was noted for the TNFalpha-308 GG genotype (P=0.055). The other polymorphisms genotyped were not associated with ICH.
A polymorphism in the inflammatory cytokine IL6, but not polymorphisms in angiogenesis-related genes, was associated with ICH presentation of BAVM. Further studies are needed to define the role of inflammatory cytokines in the pathogenesis of BAVM hemorrhage.
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