Targeted Delivery of C/EBPα -saRNA by Pancreatic Ductal Adenocarcinoma-specific RNA Aptamers Inhibits Tumor Growth In Vivo.

The 5-year survival rate for pancreatic ductal adenocarcinoma (PDAC) remains dismal despite current chemotherapeutic agents and inhibitors of molecular targets. As the incidence of PDAC constantly increases, more effective multidrug approaches must be made. Here, we report a novel method of delivering antitumorigenic therapy in PDAC by upregulating the transcriptional factor CCAAT/enhancer-binding protein-α (C/EBPα), recognized for its antiproliferative effects. Small activating RNA (saRNA) duplexes designed to increase C/EBPα expression were linked onto PDAC-specific 2'-Fluropyrimidine RNA aptamers (2'F-RNA) - P19 and P1 for construction of a cell type-specific delivery vehicle. Both P19- and P1-C/EBPα-saRNA conjugates increased expression of C/EBPα and significantly suppressed cell proliferation. Tail vein injection of the saRNA/aptamer conjugates in PANC-1 and in gemcitabine-resistant AsPC-1 mouse-xenografts led to reduced tumor size with no observed toxicity. To exploit the specificity of the P19/P1 aptamers for PDAC cells, we also assessed if conjugation with Cy3 would allow it to be used as a diagnostic tool on archival human pancreatic duodenectomy tissue sections. Scoring pattern from 72 patients suggested a positive correlation between high fluorescent signal in the high mortality patient groups. We propose a novel aptamer-based strategy for delivery of targeted molecular therapy in advanced PDAC where current modalities fail.

Leukemia cell-targeted STAT3 silencing and TLR9 triggering generate systemic antitumor immunity.

Signal transducer and activator of transcription 3 (STAT3) is an oncogene and immune checkpoint commonly activated in cancer cells and in tumor-associated immune cells. We previously developed an immunostimulatory strategy based on targeted Stat3 silencing in Toll-like receptor 9 (TLR9)-positive hematopoietic cells using CpG-small interfering RNA (siRNA) conjugates. Here, we assessed the therapeutic effect of systemic STAT3 blocking/TLR9 triggering in disseminated acute myeloid leukemia (AML). We used mouse Cbfb-MYH11/Mpl-induced leukemia model, which mimics human inv(16) AML. Our results demonstrate that intravenously delivered CpG-Stat3 siRNA, but not control oligonucleotides, can eradicate established AML and impair leukemia-initiating potential. These antitumor effects require host's effector T cells but not TLR9-positive antigen-presenting cells. Instead, CpG-Stat3 siRNA has direct immunogenic effect on AML cells in vivo upregulating major histocompatibility complex class-II, costimulatory and proinflammatory mediators, such as interleukin-12, while downregulating coinhibitory PD-L1 molecule. Systemic injections of CpG-Stat3 siRNA generate potent tumor antigen-specific immune responses, increase the ratio of tumor-infiltrating CD8(+) T cells to regulatory T cells in various organs, and result in CD8(+) T-cell-dependent regression of leukemia. Our findings underscore the potential of using targeted STAT3 inhibition/TLR9 triggering to break tumor tolerance and induce immunity against AML and potentially other TLR9-positive blood cancers.

Anxiety in children and adolescents with chronic kidney disease--multicenter national study results.

BACKGROUND/AIMS: Chronic medical illness is a significant risk factor for the development of psychiatric disorders. The aims of the study were: to investigate the level of anxiety in children with chronic kidney disease (CKD) and to identify factors associated with the presence of that emotional problem. METHODS: CKD children on hemodialysis (HD, n=22), peritoneal dialysis (PD, n=20,) and on conservative treatment (CT, n=95) were enrolled in the study. We used State-Trait Anxiety Inventory (STAI) for adolescents and STAI-C for children. Socio-demographic and physical factors were assessed. RESULTS: There was a significantly higher level of anxiety-state among HD children (8-12 years) compared with other groups of participants of the same age and Polish population norms. The level of anxiety among adolescents (13-18 years), both anxiety-state and anxiety-trait, was significantly higher in the HD group compared with other groups, which did not differ among themselves. In the HD adolescents, there was a correlation between the anxiety-state and the duration of the disease as well as with the number of hospitalizations. PD adolescents in the mainstream education had higher levels of anxiety-state and anxiety-trait compared with home schooled patients. CONCLUSIONS: Even though children and adolescents with CKD are at risk of developing a variety of emotional disorders, the level of anxiety among the researched group, with the exception of HD patients, was not significantly different than the level of anxiety among healthy subjects. Adolescents on HD who present a high level of anxiety should undergo long-term psychological treatment.

Psychosocial aspects of children and families of children treated with automated peritoneal dialysis.

BACKGROUND: The aim of this study was to analyze psychosocial aspects of chronic kidney disease (CKD) in children treated with automated peritoneal dialysis (APD). METHODS: The study assessed 41 children > 2 (range 2.1-18) years of age and their parents. Data concerning the illness and sociodemographic parameters were collected. Patients completed the Paediatric Quality of Life Inventory (PedsQL) and their parents the PedsQL-proxy version, General Health Questionnaire (GHQ-12), Berlin Social Support Scales (BSSS), and Caregiver's Burden Scale (CBS). RESULTS: Parents rated their children's overall health-related quality of life (QoL) as well as their physical and emotional functioning lower than the patients themselves. The majority of primary caregivers had a medium level of the total burden index in the CBS and higher values in the scales need for support and perceived available support than in the received support (BSSS). In the GHQ-12, 51.2% of primary caregivers had scores >2 points, which indicated the possible occurrence of abnormal mental functioning. CONCLUSIONS: Financial support for patients' families is necessary. Parents who provide primary care to children on PD require, above all, emotional support and assistance in self-fulfilment. More than half of them may have impaired mental function. There is the strong need to provide continuous psychological care for caregivers. Differences in perception of the children's activity in varied areas by the patients themselves and their caregivers may contribute to further problems within families.

Perception of health-related quality of life in children with chronic kidney disease by the patients and their caregivers: multicentre national study results.

OBJECTIVE: The aim of the study was to analyse the health-related quality of life (HRQoL) in Polish children with chronic kidney disease (CKD) dependant on the CKD stage, treatment modality and selected social life elements in families of the patients. Furthermore, potential differences between self-report and parent/proxy reports and the factors influencing them were assessed. METHODS: A total of 203 CKD children (on haemodialysis (HD), peritoneal dialysis (PD) and conservative treatment (CT)) and their 388 parent/proxies were enrolled into a cross-sectional national study. The demographic and social data were evaluated. We used the Paediatric Quality of Life Inventory 4.0 Generic Core Scales to assess the HRQoL in children. RESULTS: Health-related quality of life scores for all CKD groups were significantly lower in all domains compared with population norms, the lowest one being in the HD group. In CT children, HRQoL did not depend on the CKD stage. Both parents assessed the HRQoL of their children differently depending on their involvement in the care. There are differences between the HRQoL scores of the children and their parents. CONCLUSION: The HRQoL in children with CKD is lower than in healthy children. This is already observed in the early stages of the disease. The disease itself influences the child's mental state. Children on HD require special support on account of the lowest demonstrated overall HRQoL. Children's lower rating of the quality of life observed by their parents may render the patients unmotivated and adversely affect their adjustment to life in later years. It may also create conflicts between the parents and the children.

Synthesis and anticancer activity of 5'-chloromethylphosphonates of 3'-azido-3'-deoxythymidine (AZT).

A series of novel N-alkyl 5'-chloromethylphosphonates of 3'-azido-3'-deoxythymidine (6-15) was synthesized by means of phosphonylation of 3'-azido-3'-deoxythymidine (4) with P-chloromethylphosphonic ditriazolide (3) followed by a reaction with the appropriate amine. The synthesized phosphonamidates 6-15 were evaluated for their cytotoxic activity in two human cancer cell lines: oral (KB) and breast (MCF-7) using the sulforhodamine B (SRB) assay. The highest activity in KB human cancer cells was displayed by phosphonamidate 8 (IC(50)=5.8 µg/mL), however, this compound was less potent than the parent AZT (IC(50)=3.1 µg/mL). Phosphonamidate 10 showed only moderate activity (IC(50)=12.1 µg/mL) whereas the other phosphonamidates proved inactive. Similarly, the highest activity in MCF-7 human cancer cells was displayed by phosphonamidate 8 (IC(50)=3.7 µg/mL) but it proved somewhat less active than AZT (IC(50)=2.6 µg/mL). Some activity was also displayed by phosphonamidate 10 (IC(50)=12.8 µg/mL) but the other phosphonamidates were found inactive. Hydrolysis studies indicate that the synthesized phosphonamidates are likely to act as prodrugs of the parent nucleoside (AZT). Transport measurements showed that the most active phosphonamidates (8 and 10) were able to permeate across the intestinal epithelium in vitro. The apparent permeability coefficients determined in Caco-2 cell monolayers indicated that these compounds could be moderately absorbed in humans.

Planarians as a model of aging to study the interaction between stem cells and senescent cells in vivo.

The depletion of stem cell pools and the accumulation of senescent cells in animal tissues are linked to aging. Planarians are invertebrate flatworms and are unusual in that their stem cells, called neoblasts, are constantly replacing old and dying cells. By eliminating neoblasts in worms via irradiation, the biological principles of aging are exposed in the absence of wound healing and regeneration, making planaria a powerful tool for aging research.

Disease-related social situation in family of children with chronic kidney disease--parents` assessment. A multicentre study.

INTRODUCTION AND OBJECTIVE: Chronic kidney disease (CKD) in children burdens life of patients and their families. Little is known about parents` assessment of families' social situation. However, the knowledge of the details of a patient's and his family's life standards might influence modification and optimization of applied therapy. Therefore, the main goal of the present study was to explore the selected elements of life situation of patients suffering with CKD as well as their parents, depending on the CKD stage and appropriate treatment. MATERIALS AND METHODS: Cross-sectional national study was conducted. A total of 203 children with CKD and 388 their parent-proxies (196 women and 192 men) were enrolled into this study. Patient data and questionnaires filled by both parents, concerning social-demographic parameters and assessment of changes in families after CKD diagnosis in the child, were analysed. RESULTS: CKD children are being brought up in proper families whose financial situation is not good. Children need help in process of education. Perception of current situation differed between both parents in the change of the income source, taking care of CKD child, change in social relations and evaluating relations with medical staff. Parents do not obtain proper support from social workers. CONCLUSION: Families of CKD children require support in area of financial and educational help for school children. The discrepancies in evaluation of family situation between mothers and fathers of ill children might be the source of conflicts possibly resulting in worsening the outcome for CKD children.

Intracellular processing of immunostimulatory CpG-siRNA: Toll-like receptor 9 facilitates siRNA dicing and endosomal escape.

Dicer-substrate siRNAs equipped with CpG oligodeoxyribonucleotides overcome the major hurdle in cell-specific siRNA delivery. The CpG-siRNA molecules are actively internalized by TLR9+ cells, without the need for transfection reagents, leading to RNA interference both in vitro and in vivo. Here, we elucidate the molecular mechanisms of CpG-siRNA processing in target cells. We show that shortly after uptake into early endosomes (EE), CpG and siRNA parts of the conjugate are uncoupled in the presence of Dicer endonuclease. Diced siRNA molecules are translocated from endosomes to endoplasmic reticulum, where they can interact with the RNA interference machinery. We previously observed that even though TLR9 is not involved in CpG-siRNA uptake, it is indispensable for induction of gene silencing. To explain the role of TLR9 in intracellular processing of CpG-siRNA, we used primary macrophages derived from wild-type and Tlr9-deficient mice. Macrophages lacking TLR9 showed extended endosomal colocalization of CpG and siRNA parts of the conjugate. However, Tlr9 ablation did not interfere with the interaction of CpG-siRNA with Dicer as shown by in situ proximity ligation assay. Using CpG-siRNA labeled with pH-sensitive dye, we finally identified that lack of TLR9 in macrophages resulted in significant retention of the siRNA in endosomes. Thus, TLR9 facilitates the critical step following CpG-siRNA uncoupling, which is cytoplasmic release of the diced siRNA. These findings suggest that the class of immunostimulatory siRNAs may benefit from activation of certain endosomal immune receptors, such as TLR9, in augmented gene silencing and therapeutic efficacy.

Stability of thioester intermediates in ubiquitin-like modifications.

Ubiquitin-like modifications are important mechanisms in cellular regulation, and are carried out through several steps with reaction intermediates being thioester conjugates of ubiquitin-like proteins with E1, E2, and sometimes E3. Despite their importance, a thorough characterization of the intrinsic stability of these thioester intermediates has been lacking. In this study, we investigated the intrinsic stability by using a model compound and the Ubc9 approximately SUMO-1 thioester conjugate. The Ubc9 approximately SUMO-1 thioester intermediate has a half life of approximately 3.6 h (hydrolysis rate k = 5.33 +/- 2.8 x10(-5) s(-1)), and the stability decreased slightly under denaturing conditions (k = 12.5 +/- 1.8 x 10(-5) s(-1)), indicating a moderate effect of the three-dimensional structural context on the stability of these intermediates. Binding to active and inactive E3, (RanBP2) also has only a moderate effect on the hydrolysis rate (13.8 +/- 0.8 x 10(-5) s(-1) for active E3 versus 7.38 +/- 0.7 x 10(-5) s(-1) for inactive E3). The intrinsically high stability of these intermediates suggests that unwanted thioester intermediates may be eliminated enzymatically, such as by thioesterases, to regulate their intracellular abundance and trafficking in the control of ubiquitin-like modifications.