Electronic Structures of LNA Phosphorothioate Oligonucleotides

Important oligonucleotides in anti-sense research have been investigated in silico and experimentally. This involves quantum mechanical (QM) calculations and chromatography experiments on locked nucleic acid (LNA) phosphorothioate (PS) oligonucleotides. iso-potential electrostatic surfaces are essential in this study and have been calculated from the wave functions derived from the QM calculations that provide binding information and other properties of these molecules. The QM calculations give details of the electronic structures in terms of e.g., energy and bonding, which make them distinguish or differentiate between the individual PS diastereoisomers determined by the position of sulfur atoms. Rules are derived from the electronic calculations of these molecules and include the effects of the phosphorothioate chirality and formation of electrostatic potential surfaces. Physical and electrochemical descriptors of the PS oligonucleotides are compared to the experiments in which chiral states on these molecules can be distinguished. The calculations demonstrate that electronic structure, electrostatic potential, and topology are highly sensitive to single PS configuration changes and can give a lead to understanding the activity of the molecules.

Ankyrin-rich membrane spanning protein as a novel modulator of transient receptor potential vanilloid 1-function in nociceptive neurons

BACKGROUND

The ion channel TRPV1 is mainly expressed in small diameter dorsal root ganglion (DRG) neurons, which are involved in the sensation of acute noxious thermal and chemical stimuli. Direct modifications of the channel by diverse signalling events have been intensively investigated, but little is known about the composition of modulating macromolecular TRPV1 signalling complexes. Here, we hypothesize that the novel adaptor protein ankyrin-rich membrane spanning protein/kinase D interacting substrate (ARMS) interacts with TRPV1 and modulates its function in rodent DRG neurons.

METHODS

We used immunohistochemistry, electrophysiology, microfluorimetry and immunoprecipitation experiments to investigate TRPV1 and ARMS interactions in DRG neurons and transfected cells.

RESULTS

We found that TRPV1 and ARMS are co-expressed in a subpopulation of DRG neurons. ARMS sensitizes TRPV1 towards capsaicin in transfected HEK 293 cells and in mouse DRG neurons in a PKA-dependent manner. Using a combination of functional imaging and immunocytochemistry, we show that the magnitude of the capsaicin response in DRG neurons depends not only on TRPV1 expression, but on the co-expression of ARMS alongside TRPV1.

CONCLUSION

These data indicate that ARMS is an important component of the signalling complex regulating the sensitivity of TRPV1.

SIGNIFICANCE

The study identifies ARMS as an important component of the signalling complex regulating the sensitivity of excitatory ion channels (TRPV1) in peripheral sensory neurons (DRG neurons) and transfected cells.

6BIO Enhances Oligonucleotide Activity in Cells: A Potential Combinatorial Anti-androgen Receptor Therapy in Prostate Cancer Cells

Approximately 15%-25% of men diagnosed with prostate cancer do not survive their disease. The American Cancer Society estimated that for the year 2016 the number of prostate cancer deaths will be 26,120. Thus, there is a critical need for novel approaches to treat this deadly disease. Using high-throughput small-molecule screening, we found that the small molecule 6-bromo-indirubin-3'-oxime (6BIO) significantly improves the targeting of antisense oligonucleotides (ASOs) delivered by gymnosis (i.e., in the absence of any transfection reagents) in both the cell cytoplasm and the nucleus. Furthermore, as a single agent, 6BIO had the unexpected ability to simultaneously downregulate androgen receptor (AR) expression and AR signaling in prostate cancer cells. This includes downregulating levels of the AR-V7, a drug-resistance-related AR splice variant that is important in the progression of prostate cancer. Combining 6BIO and an anti-AR oligonucleotide (AR-ASO) can augment the downregulation of AR expression. We also demonstrated that 6BIO enhances ASO function and represses AR expression through the inhibition of the two main glycogen synthase kinase 3 (GSK-3) isoforms: GSK-3α and GSK-3β activity. Our findings provide a rationale for the use of 6BIO as a single agent or as part of a combinatorial ASO-based therapy in the treatment of human prostate cancer.

Prostate cancer, version 2.2014

Prostate cancer has surpassed lung cancer as the most common cancer in men in the United States. The NCCN Guidelines for Prostate Cancer provide multidisciplinary recommendations on the clinical management of patients with prostate cancer based on clinical evidence and expert consensus. NCCN Panel guidance on treatment decisions for patients with localized disease is represented in this version. Significant updates for early disease include distinction between active surveillance and observation, a new section on principles of imaging, and revisions to radiation recommendations. The full version of these guidelines, including treatment of patients with advanced disease, can be found online at the NCCN website.

Pharmacokinetic properties of MH84, a γ-secretase modulator with PPARγ agonistic activity

Alzheimer's disease (AD) is the most common cause of dementia. Since no causative treatment is available, new therapeutic options are utmost needed. Several pirinixic acid derivatives, including MH84 (2-((4,6-bis(4-(trifluoromethyl)phenethoxy)pyrimidin-2-yl)thio)hexanoic acid), have shown promising in vitro results as γ-secretase modulators as well as PPARγ activators as potential pharmacological compounds against AD. Using a newly developed and validated sensitive LC-MS (APCI-qTOF mass analyzer) method, the pharmacokinetic and long-term accumulating properties as well as the blood-brain-barrier permeability of MH84 were evaluated in a preclinical animal study. MH84 was administered to mice by oral gavage with a dose of 12 mg/kg. Nine time points from 0.5 to 48 h with 6 animals per point were investigated. Additionally 6 animals were fed daily, for 21 days with an identical dose to determine possible long-term accumulation in plasma and brain tissue. The sample preparation was performed by a liquid-liquid extraction on Extrelut(®) columns whereas the LC separation was operated on a MulthoHigh 100 RP 18-5 μ column (125 × 4 mm) using an isocratic mobile phase of formic acid (0.1% (v/v))-methanol mixture (11:89 (v/v)) at a flow rate of 1 ml/min. The validation confirmed the new LC-MS method to be precise, accurate and reliable. After oral application, Cmax and Tmax of unmetabolized MH84 was determined to be 10.90 μg/ml and 3h in plasma. In brain tissue a constant level of 300 to maximum 320.64 ng/g was found after 1.5-6h. Daily gavage for 21 days did not lead to a long-term drug accumulation in the brain. The efficacy of the obtained MH84 levels needs to be investigated in further preclinical pharmacodynamic animal studies.

Prostate cancer, version 1.2014

The NCCN Guidelines for Prostate Cancer provide multidisciplinary recommendations on the clinical management of patients with prostate cancer. This report highlights notable recent updates. Radium-223 dichloride is a first-in-class radiopharmaceutical that recently received approval for the treatment of patients with symptomatic bone metastases and no known visceral disease. It received a category 1 recommendation as both a first-line and second-line option. The NCCN Prostate Cancer Panel also revised recommendations on the choice of intermittent or continuous androgen deprivation therapy based on recent phase III clinical data comparing the 2 strategies in the nonmetastatic and metastatic settings.

Analgesic efficacy of opioids in chronic pain: recent meta-analyses

Opioids are regularly administered in acute and cancer pain. In chronic non-cancer pain (CNCP), however, their use is controversial. Previous meta-analyses and randomized controlled trials (RCTs) lack methodological homogeneity and comparable data. Here we analysed the maximum analgesic efficacies of opioids and non-opioids compared with placebo, and of physiotherapy and psychotherapy compared with active or waiting-list controls. We screened 3647 citations and included RCTs if treatment duration was at least 3 weeks, data were sufficient for meta-analysis, and criteria for high quality were met. Only 46 studies (10 742 patients) met the criteria. Weighted and standardized mean differences (WMD, SMD) between pain intensities were pooled to conduct separate meta-analyses for each treatment category. At the end of treatment the WMD for pain reduction (100-point scale) was 12.0 for 'strong' opioids, 10.6 for 'weak' opioids, 8.4 for non-opioids (each vs. placebo), 5.5 for psychotherapy and 4.5 for physiotherapy (each vs. active controls). Dropout rates were high in pharmacological studies. The 95% confidence intervals using the outcomes of control groups did not indicate statistical differences between efficacies of the five interventions. Because not enough eligible head-to-head trials were available, our analysis is limited to adjusted indirect comparisons. The heterogeneity of pre-post pain differences in control groups did not allow the definition of a common comparator. In conclusion, although there were statistically significant differences between maximum treatment efficacies, no intervention per se produced clinically important improvements in average pain intensity. Thus, opioids alone are inappropriate and multimodal treatment programmes may be required for CNCP.

LINKED ARTICLES

This article is part of a themed section on Opioids: New Pathways to Functional Selectivity. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2015.172.issue-2.

"Extreme" renal preservation: neoadjuvant chemotherapy and percutaneous resection for upper-tract urothelial carcinoma in a patient with solitary kidney--a case report

BACKGROUND AND PURPOSE

Renal preservation in selected patients with upper-tract urothelial cancer (UTUC) has been well described, offering an alternative to radical nephroureterectomy. We present our experiences in performing percutaneous treatments after neoadjuvant chemotherapy in one such patient with a large, complex, high-grade UTUC in a solitary kidney.

CASE REPORT

A 55-year-old woman with a solitary kidney presented with a 5.2 cm enhancing mass with calcifications involving the left renal pelvis and lower pole. Cystoscopy and retrograde pyelography demonstrated normal bladder mucosa. Ureteroscopy revealed a large, papillary tumor occupying the renal pelvis. Ureteroscopic treatment was deemed impossible because of the lesion's volume. We proceeded with percutaneous resection after downsizing the tumor after a course of neoadjuvant chemotherapy. Using a 25F resectoscope via a percutaneous tract, resection was performed to fully excise the tumor, and the patient received two postoperative chemotherapy courses. A recurrence developed within an isolated calix 8 months postoperatively, which was also managed percutaneously.

CONCLUSION

A multimodal approach in a highly motivated patient could represent a reasonable strategy for patients in whom such a therapy is desired.

Involvement of cytokines, chemokines and adhesion molecules in opioid analgesia

Tissue destruction is accompanied by an inflammatory reaction. The inflammatory reaction leads to activation of nociceptors and the sensation of pain. Several mediators are responsible for pain and hyperalgesia in inflammation including cytokines, chemokines, nerve growth factor as well as bradykinin, prostaglandins and ATP. Simulatenously however, analgesic mediators are secreted: opioid peptides, somatostatin, endocannabinoids and certain cytokines. Opioid peptides secreted from immune cells are so far the best studied peptides in peripheral inflammatory pain control. This system is hampered for example by anti-adhesion molecule treatment. Novel immunosuppressive drugs for treatment of autoimmune disease targetting cytokines, chemokines or adhesion molecules should therefore be evaluated for potential harmful effects on pain.