Combination of high on-treatment platelet aggregation and low deaggregation better predicts long-term cardiovascular events in PCI patients under dual antiplatelet therapy

High on-treatment platelet reactivity is associated with short-term major cardiovascular (CV) events in patients undergoing percutaneous coronary intervention (PCI). Maximum and final aggregation assessed by light transmission aggregometry (LTA) have both been used to predict short-term outcome after PCI, however their long-term prognostic impact remains controversial. There is currently no information regarding the prognostic role of deaggregation and its added value in combination with established aggregation parameters. About 1279 patients with symptomatic coronary artery disease (CAD) undergoing PCI were enrolled in this monocentric study. On-treatment platelet aggregation under clopidogrel maintenance therapy, as well as deaggregation was determined by maximum and final aggregation (5 min after adding of the agonist). Deaggregation was defined as slope of the tangent between Aggmax +0.5 min. Primary endpoints were the composite of myocardial infarction, stroke, and CV death or stent thrombosis according to the ARC criteria. Low deaggregation, defined as values in the lowest tertile (<1.5), was more frequent in patients with acute coronary syndromes (ACS) compared to patients with stable angina pectoris (SAP), ACS: 29.6% vs. SAP: 22.0%, p = 0.001. The combination of high on-treatment platelet reactivity, defined by the upper tertile of Aggmax and low deaggregation, was associated with significantly increased risk for combined long-term CV events. The combination of low deaggregation and high on-treatment platelet reactivity is associated with higher risk for recurrent events in patients with CAD undergoing PCI. Thus, deaggregation might be a more sensitive parameter providing added value in terms of risk prediction for long-term recurrent CV events in relation with established aggregation parameters.

The frontal cortex IGF system is down regulated in the term, intrauterine growth restricted fetal baboon

OBJECTIVE

The IGF system exerts systemic and local actions during development. We previously demonstrated that fetal cerebral cortical IGF1 is reduced at 0.5 gestation in our IUGR baboon nonhuman primate model. We hypothesized that by term protein expression of several key IGF system stimulatory peptide pathway components and downstream nutrient signaling effectors of IGF, mammalian target of rapamycin (mTOR) and S6, would decrease, indicating reduced cellular nutrient uptake and protein synthesis.

DESIGN

We fed 7 control baboons ad libitum while 6 baboons ate a globally reduced diet (70% of feed eaten by controls) from 0.16 gestation through pregnancy that produces IUGR. Fetuses were removed at Cesarean section at 0.9 gestation. Frontal cortex sections were stained for IGFI, IGFII, IGFRI, IGFR2, IGFBP2, 3, 5 and 6, and mTOR and ribosomal protein S6 and double stained with NeuN a neuron-specific nuclear antigen.

RESULTS

All proteins stained neuronal cytoplasm except IGFRI which showed only glial cell cytoplasmic and blood vessel staining. IUGR fetuses showed decreased frontal cortical immunoreactive IGFI, IGFII, IGFRI, IGFBP2, 5 and 6, and mTOR and S6 (p < 0.05). IGFBP3 increased (p < 0.05) and IGFR2 was unchanged (p > 0.05). There were no differences between male and female fetal brains.

CONCLUSIONS

When fetal nutrient availability is decreased, IUGR down regulates the IGF system and its mTOR signaling pathway in the fetal frontal cortex coincident with slowed growth. These findings emphasize the importance of the local tissue IGF system in fetal primate brain development.

Genetic variation of platelet function and pharmacology: an update of current knowledge

Platelets are critically involved in atherosclerosis and acute thrombosis. The platelet phenotype shows a wide variability documented by the inherited difference of platelet reactivity, platelet volume and count and function of platelet surface receptors. Several candidate genes have been put into focus and investigated for their functional and prognostic role in healthy individuals and patients with cardiovascular (CV) disease treated with antiplatelet agents. In addition to genetic variation, other clinical, disease-related and demographic factors are important so-called non-genetic factors. Due to the small effect sizes of single nucleotide polymorphisms (SNP) in candidate genes and due to the low allele frequencies of functional relevant candidate SNPs, the identification of genetic risk factors with high predictive values generally depends on the sample size of study cohorts. In the post-genome era new array and bioinformatic technologies facilitate high throughput genome-wide association studies (GWAS) for the identification of novel candidate genes in large cardiovascular cohorts. One of the crucial aspects of platelet genomic studies is the precise definition of a specific clinical phenotype (e.g. stent thrombosis) as this will impact importantly the findings of genomic studies like GWAS. Here, we provide an update on genetic variation of platelet receptors and drug metabolising enzymes under specific consideration of data derived by GWAS. The potential impact of this information and the role in personalised therapeutic concepts will be discussed.

A meta-analysis of CYP2D6 metabolizer phenotype and metoprolol pharmacokinetics

Metoprolol, a commonly prescribed beta-blocker, is primarily metabolized by cytochrome P450 2D6 (CYP2D6), an enzyme with substantial genetic heterogeneity. Several smaller studies have shown that metoprolol pharmacokinetics is influenced by CYP2D6 genotype and metabolizer phenotype. To increase robustness of metoprolol pharmacokinetic estimates, a systematic review and meta-analysis of pharmacokinetic studies that administered a single oral dose of immediate release metoprolol was performed. Pooled analysis (n= 264) demonstrated differences in peak plasma metoprolol concentration, area under the concentration-time curve, elimination half-life, and apparent oral clearance that were 2.3-, 4.9-, 2.3-, and 5.9-fold between extensive and poor metabolizers, respectively, and 5.3-, 13-, 2.6-, and 15-fold between ultra-rapid and poor metabolizers (all p<0.001). Enantiomer-specific analysis revealed genotype-dependent enantio-selective metabolism, with nearly 40% greater R- vs S-metoprolol metabolism in ultra-rapid and extensive metabolizers. This study demonstrates a marked effect of CYP2D6 metabolizer phenotype on metoprolol pharmacokinetics and confirms enantiomer specific metabolism of metoprolol.

Stronger prognostic power of the CpG island methylator phenotype than methylation of individual genes in neuroblastomas

OBJECTIVE

The CpG island methylator phenotype is strongly associated with poor survival in neuroblastomas. Neuroblastomas with the CpG island methylator phenotype include almost all neuroblastomas with MYCN amplification, and, even among neuroblastomas without MYCN amplification, have worse prognosis. At the same time, methylation of individual tumor-suppressor genes is also reported to be associated with poor survival. The purpose of this study was to compare the prognostic power of the CpG island methylator phenotype with that of methylation of individual genes.

METHODS

Methylation-specific polymerase chain reaction was performed for five individual genes (CASP8, EMP3, HOXA9, NR1I2 and CD44) in 140 Japanese and 152 German neuroblastomas. Kaplan-Meier analysis and log-rank tests were conducted to compare the survival between groups defined by methylation status.

RESULTS

Among the five individual genes, only CASP8 methylation had a significant association with poor overall survival both in Japanese (hazard ratio = 3.1; 95% confidence interval = 1.5-6.4; P = 0.002) and German (hazard ratio = 4.8; 95% confidence interval = 2.1-11; P = 0.0002) neuroblastomas. HOXA9 and NR1I2 methylation were associated with poor survival only in German neuroblastomas. On the other hand, the CpG island methylator phenotype had a strong and consistent association in Japanese (hazard ratio = 22; 95% confidence interval = 5.3-93; P = 1.5 × 10(-5)) and German (hazard ratio = 9.5; 95% confidence interval = 3.2-28; P = 4.7 × 10(-5)) neuroblastomas.

CONCLUSION

The CpG island methylator phenotype is likely to have stronger prognostic power than methylation of individual genes in neuroblastomas.

Instability at the FRA8I common fragile site disrupts the genomic integrity of the KIAA0146, CEBPD and PRKDC genes in colorectal cancer

Specific patterns of genomic aberrations have been associated with different types of malignancies. In colorectal cancer, losses of chromosome arm 8p and gains of chromosome arm 8q are among the most common chromosomal rearrangements, suggesting that the centromeric portion of chromosome 8 is particularly sensitive to breakage. Genomic alterations frequently occur in the early stages of tumorigenesis at specific genomic regions known as common fragile sites (cFSs). CFSs represent parts of the normal chromosome structure that are prone to breakage under replication stress. In this study, we identified the genomic location of FRA8I, spanning 530 kb at 8q11.21 and assessed the composition of the fragile DNA sequence. FRA8I encompasses KIAA0146, a large protein-coding gene with yet unknown function, as well as CEBPD and part of PRKDC, two genes encoding proteins involved in tumorigenesis in a variety of cancers. We show that FRA8I is unstable in lymphocytes and epithelial cells, displaying similar expression rates. We examined copy number alteration patterns within FRA8I in a panel of 25 colorectal cancer cell lines and surveyed publically available profiles of 56 additional colorectal cancer cell lines. Combining these data shows that focal recombination events disrupt the genomic integrity of KIAA0146 and neighboring cFS genes in 12.3% of colorectal cancer cell lines. Moreover, data analysis revealed evidence that KIAA0146 is a translocation partner of the immunoglobulin heavy chain gene in recurrent t(8;14)(q11;q32) translocations in a subset of patients with B-cell precursor acute lymphoblastic leukemia. Our data molecularly describe a region of enhanced chromosomal instability in the human genome and point to a role of the KIAA0146 gene in tumorigenesis.

[Implementation and results of a geriatric medication database]

BACKGROUND

The aim of this project was to obtain information about drug therapy in geriatric units.

PATIENTS AND METHODS

Members of the geriatrics in Bavaria database (GiB-DAT) collected data on discharge medication and transferred them to the database. A total of 88,840 data sets of geriatric rehabilitation clinics and acute geriatric units were evaluated according to the anatomical therapeutic chemical (ATC) system.

RESULTS

Patients (mean age: 81.1 years, female 67.7%) had an average of 10.4 diagnoses and took 8.0 drugs at discharge. A peak number of prescribed drugs was reached at the age of 60-70 years with a decrease in the following decades of life. Female patients received more drugs, significantly those in the decades from 71 to 80 and 81 to 90 years old. The bulk of the drugs were from the ATC groups "Cardiovascular system" (89.9%), "Nervous system" (82.3%) and "Alimentary tract and metabolism" (78%).

Low p14ARF expression in neuroblastoma cells is associated with repressed histone mark status, and enforced expression induces growth arrest and apoptosis

The TP53 tumor suppressor pathway is abrogated by TP53 mutations in the majority of human cancers. Increased levels of wild-type TP53 in aggressive neuroblastomas appear paradox but are tolerated by tumor cells due to co-activation of the TP53 ubiquitin ligase, MDM2. The role of the MDM2 antagonist, p14(ARF), in controlling the TP53-MDM2 balance in neuroblastoma is unresolved. In the present study, we show that conditional p14(ARF) expression substantially suppresses viability, clonogenicity and anchorage-independent growth in p14(ARF)-deficient or MYCN-amplified neuroblastoma cell lines. Furthermore, ectopic 14(ARF) expression induced accumulation of cells in the G1 phase and apoptosis, which was paralleled by accumulation of TP53 and its targets. Comparative genomic hybridization analysis of 193 primary neuroblastomas detected one homozygous deletion of CDKN2A (encoding both p14(ARF) and p16(INK4A)) and heterozygous loss of CDKN2A in 22% of tumors. Co-expression analysis of p14(ARF) and its transactivator, E2F1, in a set of 68 primary tumors revealed only a weak correlation, suggesting that further regulatory mechanisms govern p14(ARF) expression in neuroblastomas. Intriguingly, analyses utilizing chromatin immunoprecipitation revealed different histone mark-defined epigenetic activity states of p14(ARF) in neuroblastoma cell lines that correlated with endogenous p14(ARF) expression but not with episomal p14(ARF) promoter reporter activity, indicating that the native chromatin context serves to epigenetically repress p14(ARF) in neuroblastoma cells. Collectively, the data pinpoint p14(ARF) as a critical factor for efficient TP53 response in neuroblastoma cells and assign p14(ARF) as a neuroblastoma suppressor candidate that is impaired by genomic loss and epigenetic repression.

Differential effects of clinically used derivatives and metabolites of artemisinin in the activation of constitutive androstane receptor isoforms

BACKGROUND AND PURPOSE

Widespread resistance to antimalarial drugs requires combination therapies with increasing risk of pharmacokinetic drug-drug interactions. Here, we explore the capacity of antimalarial drugs to induce drug metabolism via activation of constitutive androstane receptors (CAR) by ligand binding.

EXPERIMENTAL APPROACH

A total of 21 selected antimalarials and 11 major metabolites were screened for binding to CAR isoforms using cellular and in vitro CAR-coactivator interaction assays, combined with in silico molecular docking. Identified ligands were further characterized by cell-based assays and primary human hepatocytes were used to elucidate induction of gene expression.

KEY RESULTS

Only two artemisinin derivatives arteether and artemether, the metabolite deoxyartemisinin and artemisinin itself demonstrated agonist binding to the major isoforms CAR1 and CAR3, while arteether and artemether were also inverse agonists of CAR2. Dihydroartemisinin and artesunate acted as weak inverse agonists of CAR1. While arteether showed the highest activities in vitro, it was less active than artemisinin in inducing hepatic CYP3A4 gene expression in hepatocytes.

CONCLUSIONS AND IMPLICATIONS

Artemisinin derivatives and metabolites differentially affect the activities of CAR isoforms and of the pregnane X receptor (PXR). This negates a common effect of these drugs on CAR/PXR-dependent induction of drug metabolism and further provides an explanation for artemisinin consistently inducing cytochrome P450 genes in vivo, whereas arteether and artemether do not. All these drugs are metabolized very rapidly, but only artemisinin is converted to an enzyme-inducing metabolite. For better understanding of pharmacokinetic drug-drug interaction possibilities, the inducing properties of artemisinin metabolites should be considered.

Amplification of satellite DNA at 16q11.2 in the germ-line of a patient with breast-cancer

Cytogenetic analyses of peripheral blood cells of breast cancer patients unveiled in one case a grossly enlarged G-band in one copy of chromosome 16 (16qh+), which scored also strongly positive in C-banding. Fluorescence in situ hybridization with both a total chromosome 16 library and with probe pHuR195 detecting locus D16Z3 further documented the increase of the copy number of the corresponding satellite DNA at 16q-11.2. Slot-blot analyses with pHuR195 revealed an approximately 10-fold amplification compared to a random selection of normal chromosomes 16. The chromosome 16 carrying amplified DNA is passed on to one of 3 children, who shows no obvious anomaly. Previous studies (Kokalj-Vokac N, Alemeida A, Gerbault-Seureau M, Malfoy B, Dutrillaux B: Gene Chromosome Cancer 7: 8-14, 1993) had revealed that satellite DNA in chromosome 16 often participates in interchromosomal recombinations, preferentially with chromosome 1, in breast cancer cells. Although the increased copy number of satellite DNA could represent a polymorphism, it might provide an enlarged target for recombination events and therefore could be a determinant for cancer predisposition.

Effects of atorvastatin metabolites on induction of drug-metabolizing enzymes and membrane transporters through human pregnane X receptor

BACKGROUND AND PURPOSE

Atorvastatin metabolites differ in their potential for drug interaction because of differential inhibition of drug-metabolizing enzymes and transporters. We here investigate whether they exert differential effects on the induction of these genes via activation of pregnane X receptor (PXR) and constitutive androstane receptor (CAR).

EXPERIMENTAL APPROACH

Ligand binding to PXR or CAR was analysed by mammalian two-hybrid assembly and promoter/reporter gene assays. Additionally, surface plasmon resonance was used to analyse ligand binding to CAR. Primary human hepatocytes were treated with atorvastatin metabolites, and mRNA and protein expression of PXR-regulated genes was measured. Two-hybrid co-activator interaction and co-repressor release assays were utilized to elucidate the molecular mechanism of PXR activation.

KEY RESULTS

All atorvastatin metabolites induced the assembly of PXR and activated CYP3A4 promoter activity. Ligand binding to CAR could not be proven. In primary human hepatocytes, the para-hydroxy metabolite markedly reduced or abolished induction of cytochrome P450 and transporter genes. While significant differences in co-activator recruitment were not observed, para-hydroxy atorvastatin demonstrated only 50% release of co-repressors.

CONCLUSIONS AND IMPLICATIONS

Atorvastatin metabolites are ligands of PXR but not of CAR. Atorvastatin metabolites demonstrate differential induction of PXR target genes, which results from impaired release of co-repressors. Consequently, the properties of drug metabolites have to be taken into account when analysing PXR-dependent induction of drug metabolism and transport. The drug interaction potential of the active metabolite, para-hydroxy atorvastatin, might be lower than that of the parent compound.

Heart rate variability - a potential early marker of sub-acute post-stroke infections

OBJECTIVE

Infection is the most relevant complication after acute ischemic stroke. Activity of the autonomic nervous system seems to control post-stroke immunodepression. We investigated heart rate variability (HRV) indices that reflect autonomic readjustments as predictors of post-stroke infection.

MATERIALS AND METHODS

Forty-three patients with acute ischemic stroke were enrolled in a prospective study. The predictability of sub-acute infections (day 4 ± 1 after admission) was investigated in 34 patients without acute infection by means of HRV indices obtained in the acute period (48 h after admission).

RESULTS

Sub-acute infection could be predicted in patients without clinical or paraclinical (white blood cell count and C-reactive protein) signs of infection in the acute period at (i) day: increased HFnorm, reduced LFnorm and LF/HF; (ii) night: reduced LF and VLF (P < 0.05).

CONCLUSIONS

HRV indices are candidates for early markers of developing post-stroke infections, preceding routine blood samples. Thus, HRV-based early diagnosis of post-stroke infection should be investigated in more detail as it may have implications as a novel tool for timely and appropriate treatment. A corresponding continuous HRV-based risk assessment using the ECG provided by the routine stroke monitoring system would be possible without any additional burden for patients and staff.

Pulmonary delivery and tissue distribution of aerosolized antisense 2'-O-Methyl RNA containing nanoplexes in the isolated perfused and ventilated rat lung

Pulmonary delivery of drugs, particularly in the treatment of lung cancer, is an attractive strategy for future targeted therapy. In this context, inhalation of nanoplexes might offer a new mode for drug delivery in gene therapy. However, limited data are currently available demonstrating pulmonary delivery, cellular uptake as well as local tolerability in lung tissue. The aim of this study was to elucidate the pulmonary delivery, tissue distribution and local tolerability of aerosolized chitosan-coated poly(lactide-co-glycolide) based nanoplexes containing antisense 2'-O-Methyl RNA (OMR). Therefore, an aerosol of OMR-nanoplexes or OMR alone was administered intra-tracheally using the model of the isolated perfused and ventilated rat lung. Localization of OMR in rat lung tissue was examined by immunohistochemistry. Administration of the OMR-nanoplex formulation resulted in significantly higher cellular OMR uptake of the respiratory epithelium in contrast to the administration of OMR alone, indicating that drug administration via aerosolized nanoplexes is able to target lung tissue. No prominent changes in lung physiology parameters were observed following inhalation, suggesting good local tolerability of OMR-nanoplex formulation.

Genomic rearrangements at the FRA2H common fragile site frequently involve non-homologous recombination events across LTR and L1(LINE) repeats

Common fragile sites (cFSs) are non-random chromosomal regions that are prone to breakage under conditions of replication stress. DNA damage and chromosomal alterations at cFSs appear to be critical events in the development of various human diseases, especially carcinogenesis. Despite the growing interest in understanding the nature of cFS instability, only a few cFSs have been molecularly characterised. In this study, we fine-mapped the location of FRA2H using six-colour fluorescence in situ hybridisation and showed that it is one of the most active cFSs in the human genome. FRA2H encompasses approximately 530 kb of a gene-poor region containing a novel large intergenic non-coding RNA gene (AC097500.2). Using custom-designed array comparative genomic hybridisation, we detected gross and submicroscopic chromosomal rearrangements involving FRA2H in a panel of 54 neuroblastoma, colon and breast cancer cell lines. The genomic alterations frequently involved different classes of long terminal repeats and long interspersed nuclear elements. An analysis of breakpoint junction sequence motifs predominantly revealed signatures of microhomology-mediated non-homologous recombination events. Our data provide insight into the molecular structure of cFSs and sequence motifs affected by their activation in cancer. Identifying cFS sequences will accelerate the search for DNA biomarkers and targets for individualised therapies.

P1-06-26: The EndoPredict Score Is a Response Predictor for Neoadjuvant Chemotherapy in ER-Positive, HER2−Negative Breast Cancer

Background:

The EndoPredict (EP) score is a multigene classifier to predict the likelihood of distant recurrence in ER-positive, HER2−negative breast cancer patients treated with adjuvant endocrine therapy. Two large randomized phase III trials involving endocrine therapy only (n &gt; 1700) demonstrated additional prognostic information of the EP score independent from clinicopathological parameters by classifying 49% as low risk. However, the predictive role of the EP is not clear. Therefore, we examined whether the EP Score also predicts sensitivity towards neoadjuvant chemotherapy in ER-positive, HER2−negative breast cancer patients.

Methods: Four publicly available gene expression data sets (Affymetrix HG-U133A) were retrieved from the gene expression omnibus (GEO) data repository. All analyzed breast cancer patients were treated with anthracycline or taxane/anthracycline-based neoadjuvant chemotherapy. Microarray cel files were MAS5 normalized with a global scaling procedure and a target intensity of 500. The analysis was restricted to ER-positive, HER2−negative breast cancer patients according to pre-specified cut-off levels for the respective ESR1/ERBB2 Affymetrix probesets. The EP score was calculated and patients were classified as having low or high risk according to the pre-specified validated cut-off value. Pathological complete response (pCR) — defined as no residual invasive cancer in the breast or lymph nodes — was used as the primary endpoint for the assessment of treatment response.

Results: The EP Score was examined in 221 ER-positive, HER2−negative breast cancer patients treated with neoadjuvant therapy. Among the 221 patients, 61 tumors (27.6%) were classified as EP-low-risk, whereas 160 tumors (72.4%) were EP-high-risk. Only one of the EP-low-risk tumors achieved a pCR after neoadjuvant therapy, whereas 24 of the 25 pCR events were classified as EP high risk. The sensitivity of the EP score was 96% and the negative predictive value 98% with an area under the receiver operating characteristic curve of 0.73.

Conclusions: The EP Score is a predictor of chemosensitivity in the neoadjuvant setting. The test correctly identified all but one of the patients achieving a pCR suggesting that the benefit of cytotoxic chemotherapy is limited to the EP high risk group.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-06-26.

ABCC multidrug transporters in childhood neuroblastoma: clinical and biological effects independent of cytotoxic drug efflux

Background

Although the prognostic value of the ATP-binding cassette, subfamily C (ABCC) transporters in childhood neuroblastoma is usually attributed to their role in cytotoxic drug efflux, certain observations have suggested that these multidrug transporters might contribute to the malignant phenotype independent of cytotoxic drug efflux.

Methods

A v-myc myelocytomatosis viral related oncogene, neuroblastoma derived (MYCN)–driven transgenic mouse neuroblastoma model was crossed with an Abcc1-deficient mouse strain (658 hMYCN^1/−, 205 hMYCN^+/1 mice) or, alternatively, treated with the ABCC1 inhibitor, Reversan (n = 20). ABCC genes were suppressed using short interfering RNA or overexpressed by stable transfection in neuroblastoma cell lines BE(2)-C, SH-EP, and SH-SY5Y, which were then assessed for wound closure ability, clonogenic capacity, morphological differentiation, and cell growth. Real-time quantitative polymerase chain reaction was used to examine the clinical significance of ABCC family gene expression in a large prospectively accrued cohort of patients (n = 209) with primary neuroblastomas. Kaplan–Meier survival analysis and Cox regression were used to test for associations with event-free and overall survival. Except where noted, all statistical tests were two-sided.

Results

Inhibition of ABCC1 statistically significantly inhibited neuroblastoma development in hMYCN transgenic mice (mean age for palpable tumor: treated mice, 47.2 days; control mice, 41.9 days; hazard ratio [HR] = 9.3, 95% confidence interval [CI] = 2.65 to 32; P < .001). Suppression of ABCC1 in vitro inhibited wound closure (P < .001) and clonogenicity (P = .006); suppression of ABCC4 enhanced morphological differentiation (P < .001) and inhibited cell growth (P < .001). Analysis of 209 neuroblastoma patient tumors revealed that, in contrast with ABCC1 and ABCC4, low rather than high ABCC3 expression was associated with reduced event-free survival (HR of recurrence or death = 2.4, 95% CI = 1.4 to 4.2; P = .001), with 23 of 53 patients with low ABCC3 expression experiencing recurrence or death compared with 31 of 155 patients with high ABCC3. Moreover, overexpression of ABCC3 in vitro inhibited neuroblastoma cell migration (P < .001) and clonogenicity (P = .03). The combined expression of ABCC1, ABCC3, and ABCC4 was associated with patients having an adverse event, such that of the 12 patients with the “poor prognosis” expression pattern, 10 experienced recurrence or death (HR of recurrence or death = 12.3, 95% CI = 6 to 27; P < .001).

Conclusion

ABCC transporters can affect neuroblastoma biology independently of their role in chemotherapeutic drug efflux, enhancing their potential as targets for therapeutic intervention.