Substance use among adolescent and young adult cancer survivors.

OBJECTIVE: Health-promoting behaviors are recommended to childhood cancer survivors (CCS) to reduce late effects resulting from cancer treatment. Understanding factors associated with substance use is needed, especially among Hispanic CCS who are underrepresented in previous studies. The objective of this study is to examine substance use behaviors of recently treated Hispanic and non-Hispanic CCS. METHODS: One hundred ninety-three Los Angeles County CCS who were diagnosed between 2000 and 2007 (54% Hispanic; mean age 19.9 years, SD = 2.8; mean age at diagnosis = 12.1, SD = 3.0; mean years since diagnosis = 7.8, SD = 2.0) provided self-reported information on substance use, demographics, clinical factors, religiosity, and depressive symptoms. Risk and protective factors for substance use were examined using multivariable logistic regression. RESULTS: Prevalence of 30-day substance use was 11%, 25%, and 14% for tobacco, alcohol, and marijuana, respectively. In controlled regression models, age was positively associated with tobacco use, binge drinking, and polysubstance use (use of at least two of the three substances). Male gender, higher depressive symptoms, and higher socioeconomic status were associated with greater marijuana use. In addition, religiosity was negatively associated with the use of all substances. CONCLUSIONS: The prevalence rates for substance use in this ethnically diverse representative sample of CCS are lower than those observed in the general population. Older CCS were at higher risk of substance use, and depression was associated with greater marijuana use. No differences by ethnicity were observed. Interventions for substance use prevention/cessation among CCS may be most effective if implemented before the age of 21 years and address mental health as part of survivorship care. Copyright © 2015 John Wiley & Sons, Ltd.

Effect of Sensorineural Hearing Loss on Neurocognitive Functioning in Pediatric Brain Tumor Survivors.

BACKGROUND: Intensified therapy with platinum-based regimens for pediatric brain tumors has dramatically increased the number of pediatric brain tumor survivors (PBTS) but frequently causes permanent sensorineural hearing loss (SNHL). Although neurocognitive decline in PBTS is known to be associated with radiation therapy (RT), SNHL represents a potential additional contributor whose long-term impact has yet to be fully determined. METHODS: The neurocognitive impact of significant SNHL (Chang scale ≥ 2b) in PBTS was assessed through a retrospective cohort study of audiograms and neurocognitive testing. Scores for neurocognitive domains and subtest task performance were analyzed to identify specific strengths and weakness for PBTS with SNHL. RESULTS: In a cohort of PBTS (n = 58) treated with platinum therapy, significant SNHL was identified in more than half (55%, n = 32/58), of which the majority required hearing aids (72%, 23/32). RT exposure was approximately evenly divided between those with and without SNHL. PBTS were 6.7 ± 0.6 and 11.3 ± 0.7 years old at diagnosis and neurocognitive testing, respectively. In multivariate analyses adjusted for RT dose, SNHL was independently associated with deficits in intelligence, executive function, and verbal reasoning skills. Subtests revealed PBTS with SNHL to have poor learning efficiency but intact memory and information acquisition. CONCLUSIONS: SNHL in PBTS increases the risk for severe therapy-related intellectual and neurocognitive deficits. Additional prospective investigation in malignant brain tumors is necessary to validate these findings through integration of audiology and neurocognitive assessments and to identify appropriate strategies for neurocognitive screening and rehabilitation specific to PBTS with and without SNHL.

Cancer-related follow-up care among Hispanic and non-Hispanic childhood cancer survivors: The Project Forward study.

BACKGROUND: Follow-up care is critical for childhood cancer survivors (CCS), who are at high risk for comorbidities and late effects of cancer treatments. Understanding the factors associated with maintaining follow-up care is needed, especially for Hispanic CCS, who have been under-represented in previous studies. METHODS: Risk factors and protective factors for receiving cancer-related follow-up care were examined among 193 Los Angeles County CCS diagnosed between 2000 and 2007 (54% Hispanic; mean ± standard deviation age, 19.9 ± 2.8 years; age at diagnosis, 12.1 ± 3.0 years; time since diagnosis, 7.8 ± 2.0 years). Self-report surveys were used to assess follow-up care, insurance status, demographics, clinical factors, and psychosocial risk (eg, depression) and protective (eg, self-efficacy [SE]) factors. Multivariable logistic regression was used to identify factors associated with the previous receipt of cancer-related follow-up care (in prior 2 years) and the intent to seek future cancer-related follow-up care. RESULTS: Seventy-three percent of CCS reported a cancer follow-up visit in the previous 2 years, which was positively associated (P < .05) with having health insurance, white ethnicity (vs Hispanic), younger age, and greater treatment intensity. Sixty-nine percent reported an intent to receive follow-up care in the next 2 years, which was positively associated (P < .05) with having health insurance and greater SE. CONCLUSIONS: Hispanics and older CCS were more likely to lack previous follow-up care. Because health insurance was strongly associated with both previous follow-up care and the intent to seek care, the current results indicate that recent changes in health coverage may improve follow-up among CCS. Interventions targeting improved SE may help increase intent to receive follow-up care for this population.

PedsQL™ Multidimensional Fatigue Scale in sickle cell disease: feasibility, reliability, and validity.

BACKGROUND: Sickle cell disease (SCD) is an inherited blood disorder characterized by a chronic hemolytic anemia that can contribute to fatigue and global cognitive impairment in patients. The study objective was to report on the feasibility, reliability, and validity of the PedsQL™ Multidimensional Fatigue Scale in SCD for pediatric patient self-report ages 5-18 years and parent proxy-report for ages 2-18 years. PROCEDURE: This was a cross-sectional multi-site study whereby 240 pediatric patients with SCD and 303 parents completed the 18-item PedsQL™ Multidimensional Fatigue Scale. Participants also completed the PedsQL™ 4.0 Generic Core Scales. RESULTS: The PedsQL™ Multidimensional Fatigue Scale evidenced excellent feasibility, excellent reliability for the Total Scale Scores (patient self-report α = 0.90; parent proxy-report α = 0.95), and acceptable reliability for the three individual scales (patient self-report α = 0.77-0.84; parent proxy-report α = 0.90-0.97). Intercorrelations of the PedsQL™ Multidimensional Fatigue Scale with the PedsQL™ Generic Core Scales were predominantly in the large (≥0.50) range, supporting construct validity. PedsQL™ Multidimensional Fatigue Scale Scores were significantly worse with large effects sizes (≥0.80) for patients with SCD than for a comparison sample of healthy children, supporting known-groups discriminant validity. Confirmatory factor analysis demonstrated an acceptable to excellent model fit in SCD. CONCLUSIONS: The PedsQL™ Multidimensional Fatigue Scale demonstrated acceptable to excellent measurement properties in SCD. The results demonstrate the relative severity of fatigue symptoms in pediatric patients with SCD, indicating the potential clinical utility of multidimensional assessment of fatigue in patients with SCD in clinical research and practice.

Mental health disparities between Hispanic and non-Hispanic parents of childhood cancer survivors.

BACKGROUND: Parents of childhood cancer survivors (CCS) experience considerable distress related to their child's cancer. However, little is known about cultural variation in this experience. We examine parental distress, specifically symptoms of post-traumatic stress (PTSS) and depression, comparing Hispanic and non-Hispanic parents of CCS. PROCEDURE: Seventy-nine Hispanic and 60 non-Hispanic parents of CCS (currently aged 14-25, off treatment ≥2 years) completed questionnaires assessing demographics, depression, PTSS, perceived stress, and child's health status/quality of life (QOL). t-Tests and chi-square statistics were used to compare differences in demographic characteristics between Hispanic and non-Hispanic parents and multivariable regression was used to determine independent risk factors associated with parental PTSS and depression. RESULTS: Hispanic parents were significantly younger, had less education, lower incomes and reported significantly more PTSS and depressive symptoms than non-Hispanic parents (all P-values < 0.0001). Among Hispanic parents, foreign birthplace predicted higher PTSS after controlling for other factors (P < 0.001). Hispanic parents, regardless of birthplace, reported more depressive symptoms than non-Hispanic parents (US-born, P < 0.05; foreign-born, P < 0.01). For PTSS and depression, there were positive relationships with parental stress and negative relationships with the child's psychosocial QOL. Hispanic and non-Hispanic CCS did not differ significantly on disease and treatment factors or health-related QOL. CONCLUSIONS: Hispanic parents of CCS may be at greater risk for poorer mental health outcomes. Ethnic-specific factors (e.g., acculturation, immigration status, and previous trauma) may influence parents' responses and adjustment to their child's cancer. Research is needed to determine how to meet the needs of the most vulnerable parents.

PedsQL™ sickle cell disease module: feasibility, reliability, and validity.

BACKGROUND: Sickle cell disease (SCD) is an inherited chronic disease that is characterized by complications such as recurrent painful vaso-occlusive events that require frequent hospitalizations and contribute to early mortality. The objective of the study was to report on the initial measurement properties of the new PedsQL™ SCD Module for pediatric patient self-report ages 5-18 years and parent proxy-report for ages 2-18 years. PROCEDURE: The 43-item PedsQL™ SCD Module was completed in a multisite study by 243 pediatric patients with SCD and 313 parents. Participants also completed the PedsQL™ 4.0 Generic Core Scales and PedsQL™ Multidimensional Fatigue Scale. RESULTS: The PedsQL™ SCD Module Scales evidenced excellent feasibility, excellent reliability for the Total Scale Scores (patient self-report α = 0.95; parent proxy-report α = 0.97), and good reliability for the nine individual scales (patient self-report α = 0.69-0.90; parent proxy-report α = 0.83-0.97). Intercorrelations with the PedsQL™ Generic Core Scales and PedsQL™ Multidimensional Fatigue Scales were medium (0.30) to large (0.50) range, supporting construct validity. PedsQL™ SCD Module Scale Scores were generally worse for patients with severe versus mild disease. Confirmatory factor analysis demonstrated an acceptable to excellent model fit. CONCLUSIONS: The PedsQL™ SCD Module demonstrated acceptable measurement properties. The PedsQL™ SCD Module may be utilized in the evaluation of SCD-specific health-related quality of life in clinical research and practice. In conjunction with the PedsQL™ Generic Core Scales and the PedsQL™ Multidimensional Fatigue Scale, the PedsQL™ SCD Module will facilitate the understanding of the health and well-being of children with SCD.

Antineoplastic agent busulfan regulates a network of genes related to coagulation and fibrinolysis.

Purpose Hepatic veno-occlusive disease (HVOD) is one of the major complications following hematopoietic stem cell transplantation (HSCT). Although high-dose busulfan is associated with the development of HVOD, the underlying molecular mechanisms are still unknown.Methods Transcriptional gene regulation by busulfan was profiled using Affymetrix GeneChip® Human Genome U133 Plus 2.0 arrays. Messenger RNA (mRNA) expression of regulated genes was assessed by TaqMan real-time polymerase chain reaction (PCR), and protein expression and secretion was determined by enzyme-linked immunosorbent assay (ELISA)in cell supernatants, lysates, and patient plasma.Results Plasma levels of plasminogen activator inhibitor(PAI)-1 significantly increased 48 h after starting busulfan treatment IV in children preconditioned for HSCT. In vitro,busulfan significantly induced plasminogen activator inhibitor-1 (PAI-1) expression in endothelium-like ECV304 cells in a concentration- and time-dependent manner. Comparative transcriptional profiling of busulfan-treated and control ECV304 cells identified differential expression of genes related to coagulation and fibrinolysis, including tissue factor, tissue factor pathway inhibitor-1, protein S, thrombospondin-1, urokinase receptor, and PAI-1, as well as activin A and transforming growth factor beta 1 (TGF-ß1). Ingenuity pathway analysis (IPA) suggested TGF-ß1 as a central modulator of gene regulation by busulfan. Consequently, expression of tissue factor, urokinase receptor, and PAI-1 mRNA and PAI-1 protein secretion induced by busulfan were significantly reduced by the activin A/TGF-ß1 inhibitor SB 431542 in ECV304 and primary endothelial cells.Conclusions This is the first report that directly relates busulfan exposure to antifibrinolytic activity by PAI-1 and hypercoagulation possibly mediated by members of the TGF-ß1 family. This suggests further research to evaluate activin A and TGF-ß1 as potential targets for HVOD treatment.

Proteomic analysis of doxorubicin-induced changes in the proteome of HepG2cells combining 2-D DIGE and LC-MS/MS approaches.

HepG-2 cells are widely used as a cell model to investigate hepatocellular carcinomas and the effect of anticancer drugs such as doxorubicin, an effective antineoplastic agent, which has broad antitumoral activity against many solid and hematological malignancies. To investigate the effect of doxorubicin on the protein pattern, we used complementary proteomic workflows including 2-D gel-based and gel-free methods. The analysis of crude HepG2 cell extracts by 2-D DIGE provided data on 1835 protein spots which was then complemented by MS-centered analysis of stable isotope labeling by amino acids in cell culture-labeled cells. The monitoring of more than 1300 distinct proteins, including proteins of the membrane fraction provides the most comprehensive overview on the proteome of the widely used model cell line HepG2. Of the proteins monitored in total, 155 displayed doxorubicin-induced changes in abundance. Functional analysis revealed major influences of doxorubicin on proteins involved in protein synthesis, DNA damage control, electron transport/mitochondrial function, and tumor growth. The strongest decrease in level was found for proteins involved in DNA replication and protein synthesis, whereas proteins with a function in DNA damage control and oxidative stress management displayed increased levels following treatment with doxorubicin compared with control cells. Furthermore, the doxorubicin-associated increase in levels of multiple forms of keratins 8, 18, and 19 and other structural proteins revealed an influence on the cytoskeleton network.

Expression of ABC-type transport proteins in human platelets.

We have identified the ATP-binding cassette (ABC) transporter ABCC4 as an active constituent of mediator-storing granules in human platelets. In addition to multidrug resistance protein 4, other ABC-type transport proteins may contribute to platelet secretory function as well as determine intended or adverse effects of drugs. Here, we provide a comprehensive expression profiling of ABC transporters in human platelets based on a novel screening approach by combining the TaqMan low-density array RNA screening platform with a recently developed liquid chromatography/mass spectrometry (MS)/MS method for the simultaneous detection of membrane proteins. Transcripts of 25 ABC transporters were detected and showed differential expression compared with megakaryocytic progenitor cells. On the protein level ABCA7, ABCB4, ABCC1, ABCC3 and ABCC4 were identified by liquid chromatography/MS/MS and localized by immunofluorescence microscopy. Their functions may be related to glutathione and lipid homeostasis, secretion of lipid mediators, cell protection as well as drug transport.

Human platelets express organic anion-transporting peptide 2B1, an uptake transporter for atorvastatin.

Statins are widely used to treat dyslipidemia. Effects of statins in addition to low-density lipoprotein lowering include altered platelet aggregation, requiring drug uptake into platelets. Possible candidates for mediating intraplatelet accumulation of statins include members of the organic anion-transporting polypeptide family such as OATP2B1 (SLCO2B1), a high-affinity uptake transporter for atorvastatin. Therefore, we analyzed OATP expression, localization, and function in human platelets. OATP2B1, but not OATP1B1, was detected in platelets and megakaryocytes on transcript and protein levels. Protein localization was almost exclusively confined to the plasma membrane. Moreover, we could demonstrate significant inhibition of estrone sulfate uptake into platelets by atorvastatin as well as direct transport of atorvastatin into platelets using a liquid chromatography-tandem mass spectrometry method. As a consequence of OATP2B1-mediated uptake of atorvastatin, we observed significant atorvastatin-mediated reduction of thrombin-induced Ca(2+) mobilization in platelets (37.3 +/- 6.7% of control at 15 microM atorvastatin), mechanistically explainable by reduced lipid modification of signal proteins. This effect was reversed by addition of mevalonate. Finally, we demonstrated expression of HMG-CoA reductase, the primary target of atorvastatin, in platelet cytosol. In conclusion, OATP2B1 is an uptake transporter expressed in platelets and is involved in statin-mediated alteration of platelet aggregation.

Toll-like receptor-4 deficiency attenuates doxorubicin-induced cardiomyopathy in mice.

BACKGROUND: Cardiac inflammation and generation of oxidative stress are known to contribute to doxorubicin (Dox)-induced cardiomyopathy. Toll-like receptors (TLRs) are a part of the innate immune system and are involved in cardiac stress reactions. Since TLR4 might play a relevant role in cardiac inflammatory signalling, we investigated whether or not TLR4 is involved in Dox-induced cardiotoxicity. METHODS AND RESULTS: Five days after a single injection of Dox (20 mg/kg; i.p.), left ventricular pressure-volume loops were measured in wild-type and TLR4-deficient mice (TLR4-/-) Dox-treated and control mice. Analyses of possible pathophysiological mechanisms were performed in left ventricular tissue and isolated myocytes, respectively. Dox injection resulted in an impairment of left ventricular function and neurohumoral activation, indexed by increased ET-1 expression. This was further associated with an increase in cardiac oxidative stress, inflammation and apoptosis, as indicated by an up-regulation of cardiac lipid peroxidation, TNF-alpha expression and enhanced content of TUNEL-positive cells. In contrast, TLR4-/- Dox mice showed improved left ventricular function with reduced oxidative and inflammatory stress response including reduced cardiac apoptosis. These results were found to be associated with an increase of GATA-4 expression. CONCLUSIONS: TLR4 deficiency improves left ventricular function and attenuates pathophysiological key mechanisms in Dox-induced cardiomyopathy.

Subfractionation and purification of intracellular granule-structures of human platelets: an improved method based on magnetic sorting.

Functional analysis of intracellular structures requires isolation and purification of these cellular compartments. With regard to platelet function both delta and alpha granules are relevant target structures. However, the availability of sufficient purification protocols for these structures is rather limited and restricted to density gradient centrifugation. Because this method is time-consuming and the resulting products are often of limited purity, we designed a new purification method based on immunolabeling followed by magnetic sorting. We directly compared this new method with the conventional method of ultracentrifugation. We were able to get highly purified subcellular fractions of human platelets using several antibodies against specific markers for dense granules (LAMP2), alpha granules (P-selectin) and the plasma membrane (GPIIb/IIIa) in combination with antibody-coated magnetic beads. In the respective fractions the marker proteins used for isolation as well as further independent, structure specific markers (for example MRP4 for dense granules, von Willebrand factor (vWF) for alpha granules and protein disulfide isomerase, PDI and GPIb beta, for plasma membrane) could be detected by Western blotting. The method describes purification of membranal structures of human platelets such as the plasma membrane and both types of granules. Therefore, studies requiring highly purified material (e.g. identification of specific transporters and receptors) will benefit from these results.

Impact of Caregiving for a Child With Cancer on Parental Health Behaviors, Relationship Quality, and Spiritual Faith: Do Lone Parents Fare Worse?

Caregiving stress has been associated with changes in the psychological and physical health of parents of children with cancer, including both partnered and single parents. While parents who indicate "single" on a demographic checklist are typically designated as single parents, a parent can be legally single and still have considerable support caring for an ill child. Correspondingly, an individual can be married/partnered and feel alone when caring for a child with serious illness. In the current study, we report the results from our exploratory analyses of parent self-reports of behavior changes during their child's treatment. Parents (N = 263) of children diagnosed with cancer were enrolled at 10 cancer centers. Parents reported significant worsening of all their own health behaviors surveyed, including poorer diet and nutrition, decreased physical activity, and less time spent engaged in enjoyable activities 6 to 18 months following their child's diagnosis. More partnered parents found support from friends increased or stayed the same since their child's diagnosis, whereas a higher proportion of lone parents reported relationships with friends getting worse. More lone parents reported that the quality of their relationship with the ill child's siblings had gotten worse since their child's diagnosis. Spiritual faith increased for all parents.

Expression and localization of P-glycoprotein in human heart: effects of cardiomyopathy.

ABC-type transport proteins, such as P-glycoprotein (P-gp), modify intracellular concentrations of many substrate compounds. They serve as functional barriers against entry of xenobiotics (e.g., in the gut or the blood-brain barrier) or contribute to drug excretion. Expression of transport proteins in the heart could be an important factor modifying cardiac concentrations of drugs known to be transported by P-gp (e.g., beta-blockers, cardiac glycosides, doxorubicin). We therefore investigated the expression and localization of P-gp in human heart. Samples from 15 human hearts (left ventricle; five non-failing, five dilated cardiomyopathy, and five ischemic cardiomyopathy) were analyzed for expression of P-gp using real-time RT-PCR, immunohistochemistry, and in situ hybridization. Immunohistochemistry revealed expression of P-gp in endothelium of both arterioles and capillaries of all heart samples. Although P-gp mRNA was detected in all samples, its expression level was significantly reduced in patients with dilated cardiomyopathy. We describe variable expression of P-gp in human heart and its localization in the endothelial wall. Thus, intracardiac concentrations of various compounds may be modified, depending on the individual P-gp level.

Involvement of AP-2 binding sites in regulation of human beta-glucuronidase.

The lysosomal hydrolase beta-glucuronidase (beta-gluc) can be used for the bioactivation of non-toxic glucuronide prodrugs of anticancer agents. The enzyme is present at high levels in many tumours and hence may lead to an enhanced drug targeting by tumour-selective release of the active anticancer drug. Individual expression and regulation of this enzyme is one factor modulating the bioactivation of glucuronide prodrugs. Nevertheless, in contrast to murine beta-gluc, which is inducible by androgens, the human enzyme has been regarded as an unregulated housekeeping gene due to a lacking TATA box and high G+C contents within the putative promotor sequence. Despite these facts, we were able to demonstrate downregulation of human beta-gluc expression by the calcium ionophore A23187 and the calcium ATPase inhibitor thapsigargin in the human hepatoma cell line HepG2. However, cis-acting elements responsible for this regulation have not yet been identified. We therefore characterised the 5'-untranslated region of the human beta-gluc gene using transient transfection assays with promotor-luciferase constructs in HepG2 cells and cloned fragments between 3,770 bp and 107 bp. A23187 reduced the beta-gluc promotor activity. This effect disappeared using fragments smaller than 356 bp. Using site-directed in vitro mutagenesis and gel-electrophoretic-mobility shift assays, we found evidence of an involvement of transcription factor activating protein-2 (AP-2) binding sites on the regulation of human beta-glucuronidase by A23187. Our studies provide a basis for the understanding of the transcriptional regulation of the human beta-glucuronidase gene and could be useful for the optimisation of glucuronide prodrug therapy.

Evaluation of the psychometric properties of the Pediatric Parenting Stress Inventory (PPSI).

OBJECTIVE: This work evaluated the psychometric properties of the Pediatric Parenting Stress Inventory (PPSI), a new measure of problems and distress experienced by parents of children with chronic illnesses. METHOD: This secondary data analysis used baseline data from 1 sample of English-, Spanish-, and Hebrew-speaking mothers of children recently diagnosed with cancer (n = 449) and 1 sample of English- and Spanish-speaking mothers of children recently diagnosed with cancer (n = 399) who participated in 2 problem-solving skills training interventions. The PPSI was administered at baseline with other measures of maternal distress. Factor structure was evaluated using exploratory factor analysis (EFA) on the first sample and confirmatory factor analysis (CFA) on both samples. Internal consistency was evaluated using Cronbach's alpha. Construct validity was assessed via Spearman correlations with measures of maternal distress. RESULTS: EFA resulted in a stable four-factor solution with 35 items. CFA indicated that the four-factor solution demonstrated reasonable fit in both samples. Internal consistency of the subscales and full scale was adequate to excellent. Construct validity was supported by moderate to strong correlations with measures of maternal distress, depression, and posttraumatic stress symptoms. CONCLUSIONS: The PPSI demonstrated good psychometric properties in assessing current problems and distress experienced by mothers of children newly diagnosed with cancer. This tool may be used to identify individualized targets for intervention in families of children with cancer. Future studies could evaluate the utility and psychometrics of the PPSI with other pediatric populations.

Acute exposure to doxorubicin results in increased cardiac P-glycoprotein expression.

Doxorubicin is a frequently used anticancer drug, but its use is restricted due to the occurrence of severe side effects, namely strong cardiotoxicity. It is known from cancer cells that doxorubicin enhanced the expression of its efflux pump P-glycoprotein (P-gp), which may modulate local drug concentrations. We therefore studied the cardiac expression of P-gp in doxorubicin-treated mice. Mice were treated with doxorubicin, and P-gp expression was studied after 1, 3, and 5 days. Thereby, we could show a significant upregulation of abcb1a (162 ± 15% of control) and abcb1b (418 ± 110% of control) mRNA transcripts after 3 days. On protein level, western blot analysis and immunofluorescence staining revealed a similar finding 5 days after doxorubicin administration. In addition, these results could be confirmed by in vitro models using primary rat cardiomyocytes and the murine cardiomyocyte-like HL-1 cells. Besides an enhanced mRNA and protein expression, doxorubicin-treated HL-1 cells also demonstrated an enhanced P-gp function as assessed by a daunorubicin accumulation assay. Our in vivo and in vitro results demonstrate a cardiac upregulation of P-gp in doxorubicin-treated mice on expression and functional level. This finding may be relevant for cardiac tissue concentrations of P-gp substrates and may represent a mechanism in cardiac self-protection against xenobiotics.

Quantifying the relationship among hospital design, satisfaction, and psychosocial functioning in a pediatric hematology-oncology inpatient unit.

BACKGROUND: Studies show that hospital built environments can affect physical and psychological outcomes and healthcare satisfaction in adults, but pediatric research is sparse. OBJECTIVE: To investigate the effects of the built environment on hospitalized pediatric hematology-oncology patients and their parents by testing the hypothesis that perceived built environment satisfaction mediates the relationship between the objective built environment and psychosocial functioning, as well as parental healthcare satisfaction. METHODS: The hospital built environment was evaluated subjectively through the PedsQL™ Hospital Healing Environment Module satisfaction questionnaires and objectively by quantifying environmental features. Outcomes for patients and parents included present functioning and affect. Healthcare satisfaction was also assessed for parents. Structural equation modeling (SEM) was used to test the mediational hypothesis. SUBJECTS: Participants were 90 hospitalized pediatric hematology-oncology patients and 149 parents of pediatric hematology-oncology patients. RESULTS: For both parents and children, analyses revealed a significant positive relationship between the quality of the objective built environment and built environment satisfaction. For parents, significant relationships emerged in the expected direction between built environment satisfaction and present functioning, healthcare satisfaction, and negative affect. CONCLUSIONS: Both pediatric hematology-oncology patients and their parents can reliably report their own perceived built environment satisfaction, which is significantly related to the quality of the objective built environment. For parents, results support the mediational hypothesis, highlighting the importance that perceived built environment satisfaction plays in psychosocial functioning and healthcare satisfaction.

Pretreatment with statin attenuates the cardiotoxicity of Doxorubicin in mice.

Cardiotoxicity, which may result from intense cardiac oxidative stress and inflammation, is the main limiting factor of the anticancer therapy using doxorubicin. Because statins might exert beneficial pleiotropic cardiovascular effects, among other things, by anti-inflammatory and antioxidative mechanisms, we investigated whether or not fluvastatin pretreatment can attenuate doxorubicin-induced cardiotoxicity. Five days after a single injection of doxorubicin (20 mg/kg; i.p.), left ventricular (LV) function was measured in fluvastatin-treated (DoxStatin; 100 mg/kg/day, p.o.) and saline-treated (doxorubicin) mice (n = 8 per group) by a micro conductance catheter. Untreated mice served as controls (placebo; n = 8 per group). After measurement of cardiac function, LV tissues were analyzed by molecular biological and immunohistologic methods. Injection resulted in significantly impaired LV function (LV pressure, -29%; dp/dtmax, -45%; cardiac output, -68%; P < 0.05) when compared with placebo. This was associated with a significant increase in cardiac oxidative stress, inflammation and apoptotic mechanisms, as indicated by significant increased cardiac lipid peroxidation activity, protein expression of nitrotyrosine, tumor necrosis factor alpha and Bax (P < 0.05). In contrast, DoxStatin mice showed improved LV function (LV pressure, +24%; dp/dtmax, +87%; cardiac output, +87%; P < 0.05) when compared with untreated doxorubicin mice. This was associated with reduced cardiac expression of nitrotyrosine, enhanced expression of the mitochondrial located antioxidative SOD 2, attenuated mitochondrial apoptotic pathways, and reduced cardiac inflammatory response. Statin pretreatment attenuates doxorubicin-induced cardiotoxicity via antioxidative and anti-inflammatory effects.

Reduced expression of Rho guanine nucleotide dissociation inhibitor-alpha modulates the cytotoxic effect of busulfan in HEK293 cells.

High-dose busulfan is an important component in many conditioning protocols for hematopoietic stem cell or bone marrow transplantation. Treatment with busulfan results in the inhibition of cell cycle progression and apoptosis of tumor cells. As Rho GTPases are involved in cell cycle regulation, we investigated the influence of modified Rho guanine nucleotide dissociation inhibitor-alpha (GDI), a physiological inhibitor of Rho GTPases, on busulfan activity in cancer cells. RhoGDIalpha has been shown to be overexpressed in multiple types of tumors such as ovarian and breast cancer. To investigate the role of RhoGDIalpha, we established a RhoGDIalpha knockdown by the transient transfection of HEK293 cells with specific small interfering RNA resulting in strongly reduced RhoGDIalpha mRNA and protein expression. Other members of the RhoGDI family such as RhoGDIbeta and RhoGDIgamma were not affected. In RhoGDIalpha knockdown cells, cell cycle regulation was not altered by the downregulation of RhoGDIalpha; however, the rate of apoptotic cells increased when compared with the control small interfering RNA-transfected cells. In addition, treatment of cells with busulfan resulted in a further increased apoptotic rate, as determined by fluorescence-activated cell sorter analysis and caspase-3 activation. Such a sensitization of RhoGDIalpha small interfering RNA transfected cells was also found upon treatment with doxorubicin and taxol. In summary, we could demonstrate that the expression of RhoGDIalpha influences the sensitivity of cells toward busulfan-induced cytotoxicity.