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BackgroundAllograft models enable characterisation of genomic drivers and treatment responses by modelling immune and micro-environmental changes more accurately than xenografts. Despite this, few models are available to the prostate cancer (PCa) community. This study presents a novel allograft model of high-risk, localised PCa. In characterising this model we have focused on its response to radiotherapy (RT).MethodsThe DVL3 cell line was derived from a transgenic trp53-/-/Pten-/- mouse model and characterised both in vitro and in vivo. The DVL3 cells were allografted and response to RT was investigated and compared to the TRAMP-C1 model. Extensive tumour profiling in the DVL3 model was performed using flow cytometry, immunohistochemistry and RNA-seq.ResultsIn vitro the DVL3 cells expressed basal and luminal markers. DVL3 cells formed tumours with distinct glandular morphology which expressed androgen receptor, similar to human localised PC. DVL3 tumour growth was delayed following administration of fractionated RT, with infiltration of myeloid derived suppressor cells (MDSC).ConclusionsThe DVL3 allograft model represents substantial progress in PCa modelling, displaying; luminal differentiation, strong AR expression, and an immunosuppressive microenvironment, similar to observations in high-risk PCa patients. This model is ideally suited for development and validation of novel therapeutics, in particular immune-modulatory agents in combination with RT.

Background Despite growing concern about the increased rates of synthetic cannabinoid (SC) use and their effects, only limited data are available that addresses these issues. This study assessed the extent of SC product use and reported effects among a cohort of adult marijuana and tobacco users. Methods A brief telephone interview was conducted with individuals who had given permission to be contacted for future research while screening for a cannabis/nicotine dependence medication development study (NCT01204723). Results Respondents ( N = 42; 88% participation rate) were primarily young adults, male, racially diverse, and high school graduates. Nearly all currently smoked tobacco and cannabis, with 86% smoking cannabis on 5 or more days per week. Nearly all (91%) were familiar with SC products, half (50%) reported smoking SC products previously, and a substantial minority (24%) reported current use (i.e., past month). Despite a federal ban on 5 common SCs, which went into effect on March 1, 2011, a number of respondents reported continued SC product use. Common reasons reported for use included, but were not limited to, seeking a new “high” similar to that produced by marijuana and avoiding drug use detection via a positive urine screen. The primary side effects were trouble thinking clearly, headache, dry mouth, and anxiety. No significant differences were found between synthetic cannabinoid product users (ever or current) and nonusers by demographics or other characteristics. Conclusions Among current marijuana and tobacco users, SC product consumption was common and persisted despite a federal ban. The primary reasons for the use of SC-containing products seem to be to evade drug detection and to experience a marijuana-like high.

Cannabis, the most commonly used illicit substance, exerts its primary psychoactive effect via delta-9 tetrahydrocannabinol (Δ(9) -THC) agonism of cannabinoid receptor type 1 (CB1). Some users develop a cannabis use disorder and physical dependence manifested by withdrawal symptoms during abstinence. Hence, there is growing public health concern about increasing use of a new generation of synthetic cannabinoid (SC) agonists (eg, JWH-018, CP 47,497) marketed as natural herbal incense mixtures under brand names such as "Spice" and "K2." Anecdotal reports suggest overlapping effects with marijuana when the mixtures are smoked, however, systematic evaluation of SC-related psychoactive properties and adverse effects is lacking. We conducted a systematic review of published reports on SC clinical effects in humans. Most highlight potential toxicity such as acute anxiety and psychosis. In addition, we carefully document three cases in which experienced marijuana users meeting criteria for cannabis dependence with physiologic dependence smoked SC products regularly. The SC mixture effects were reportedly similar to marijuana and well tolerated. The individuals all reported that SC product use effectively alleviated cannabis withdrawal. Biopsychosocial factors associated with SC initiation and usage by the cases help to shed light on psychopharmacologic, clinical, and public health aspects of SC product consumption.

Gamma-aminobutyric acid A (GABA(A)) receptors moderate several of the behavioral effects of alcohol. In fact, recent studies have shown an association between the gene for the alpha2-subunit of the GABA(A) receptor (GABRA2) and alcoholism. In the present study, we examined the functional relevance of the GABRA2 gene in alcohol dependence by assessing brain GABRA2 mRNA and GABA(A)alpha2-subunit protein levels in post-mortem prefrontal cortical tissue collected from control and alcohol-dependent individuals. In addition, using an endophenotype approach, we tested whether the GABRA2 gene moderates sensitivity to the acute effects of alcohol in two independent samples from distinct human alcohol challenge studies. Results indicated that GABRA2 mRNA levels significantly differed by GABRA2 genotype. GABRA2 single nucleotide polymorphisms (rs573400, rs279871 and rs279858) were significantly associated with sensitivity to the acute effects of alcohol. Specifically, there was a significant main effect of GABRA2 x breath alcohol concentration on several measures of subjective responses to alcohol, including the hedonic value of alcohol. Importantly, reanalysis of a previous intravenous alcohol administration study confirmed the results of the oral alcohol challenge study. In summary, these results extend previous findings and provide new insights into the putative biobehavioral mechanisms that may moderate the association between the GABRA2 gene, sensitivity to the acute effects of alcohol and ultimately alcohol dependence.

The makaluvamines are marine natural products that were originally isolated because of their cytotoxicity in a cell-based mechanism screen. They have significant anti-cancer activity in animal models. There is, however, disagreement in the literature as to whether these compounds target topoisomerase II via a clinically relevant mechanism. This work shows that the makaluvamines can induce dose-dependent DNA cleavage via topoisomerase II. For most of the makaluvamines the levels of cleavage are significantly below those achieved by equimolar concentrations of etoposide. To some extent these results might explain the discrepancies present in the literature.

Context Given the probable importance of the α4 subunit of the neuronal nicotinic acetylcholine receptor, the gene that codes for this subunit ( CHRNA4 ) represents an excellent starting point for a genetic investigation of smoking behavior. Objective To achieve a better understanding of the role of this gene in the cause and treatment of tobacco dependence, we adopted a transdisciplinary pharmacogenetic approach. Design Study at the behavioral and clinical levels of analysis. Setting Academic research. Participants Smokers (n = 316) between the ages of 18 and 50 years were recruited from the Denver, Colorado, metropolitan area. Main Outcome Measures Bioinformatics analyses, cell culture experiments, and analyses of CHRNA4 expression and nicotine binding in postmortem human brain tissue advanced 2 single-nucleotide polymorphisms ( rs6122429 and rs2236196 ). Results Both single-nucleotide polymorphisms were associated with subjective responses to smoking in the laboratory among 316 smokers. Likewise, among 353 participants in a clinical trial, rs2236196 was associated with smoking cessation outcomes. Conclusions Results of analyses ranging from basic biological approaches to clinical outcome data provide consistent evidence that 2 single-nucleotide polymorphisms in CHRNA4 are functional at a biological level and are associated with nicotine dependence phenotypes. This interdisciplinary approach to the genetics of nicotine dependence provides a model for testing how functional genetic variation is translated from changes in messenger RNA and protein to individual differences in behavior and treatment outcome.

Background: Altered noradrenergic neurotransmission is associated with depression and may contribute to drug abuse and alcoholism. Differential initial sensitivity to ethanol is an important predictor of risk for future alcoholism, making the inbred long-sleep (ILS) and inbred short-sleep (ISS) mice a useful model for identifying genes that may contribute to alcoholism. Methods: In this study, molecular biological, neurochemical, and behavioral approaches were used to test the hypothesis that the norepinephrine transporter (NET) contributes to the differences in ethanol-induced loss of righting reflex (LORR) in ILS and ISS mice. Results: We used these mice to investigate the NET as a candidate gene contributing to this phenotype. The ILS and ISS mice carry different DNA haplotypes for NET, showing eight silent differences between allelic coding regions. Only the ILS haplotype is found in other mouse strains thus far sequenced. Brain regional analyses revealed that ILS mice have 30 to 50% lower [3H]NE uptake, NET binding, and NET mRNA levels than ISS mice. Maximal [3H]NE uptake and NET number were reduced, with no change in affinity, in the ILS mice. These neurobiological changes were associated with significant influences on the behavioral phenotype of these mice, as demonstrated by (1) a differential response in the duration of ethanol-induced LORR in ILS and ISS mice pretreated with a NET inhibitor and (2) increased ethanol-induced LORR in LXS recombinant inbred (RI) strains, homozygous for ILS in the NET chromosomal region (44–47 cM), compared with ISS homozygous strains. Conclusions: This is the first report to suggest that the NET gene is one of many possible genetic factors influencing ethanol sensitivity in ILS, ISS, and LXS RI mouse strains.

Multiple administrations of methamphetamine (METH) rapidly decreased serotonin (5HT) transporter (SERT) function in rat striatum and hippocampus. The purpose of this study was to identify the mechanisms/ factors contributing to this METH-induced decrease in SERT function. Multiple high-dose METH injections rapidly decreased 5HT uptake without altering binding of the 5HT transporter ligand paroxetine. Hyperthermia contributed to this deficit in transporter function in striatum and hippocampus, as prevention of METH-induced hyperthermia attenuated this decrease. A role for dopamine (DA) was suggested by findings that pretreatment with the tyrosine hydroxylase inhibitor alpha-methyl-p-tyrosine, the D1 antagonist SCH-23390, or the D2 antagonist eticlopride attenuated the METH-induced decrease in striatal, but not hippocampal, SERT activity. These effects were independent of the ability of these DA-antagonizing drugs to prevent METH-induced hyperthermia. These results suggest that DA contributes to the decrease in SERT function caused by multiple METH injections in the striatum, but not hippocampus, and that hyperthermia facilitates these deficits in SERT function in both brain regions. In contrast, the response of SERT to a single administration of METH was DA and hyperthermia independent. These findings suggest that the mechanisms/ factors involved in decreasing SERT activity after a single administration of METH are distinct from that caused by multiple administrations.

High-dose administrations of amphetamine, methamphetamine, cathinone, methcathinone or methylenedioxymethamphetamine rapidly decrease dopamine and serotonin transporter function in vivo, as assessed in striatal synaptosomes obtained from drug-treated rats. In contrast, high-dose injections of fenfluramine, cocaine or methylphenidate had little or no effect on the activity of these transporters. Interestingly, the capacity of these agents to directly alter dopamine and serotonin uptake, as assessed in vitro by direct application to rat striatal synaptosomes, did not predict their potential to modulate transporter activity following in vivo administration. These findings demonstrate heretofore-unreported differences in the effects of these agents on monoamine transporter function, and a distinction between drug effects after direct application in vitro vs. administration in vivo.

Administration of high doses of methamphetamine (METH) produces both short- and long-term enzymatic deficits in central monoaminergic systems. To determine whether a correlative relationship exists between these acute and long-term consequences of METH treatment, in the present study we examined the regional effects of METH on tryptophan hydroxylase (TPH) and tyrosine hydroxylase (TH) activities in various regions of the caudate nucleus, nucleus accumbens, and globus pallidus. A single METH administration decreased TPH activity 1 h after treatment in the globus pallidus, in the nucleus accumbens, and throughout the caudate; in the anterior caudate, the ventral-medial was more affected than the dorsal-lateral region. In contrast, TH activity was not decreased in either the caudate or the globus pallidus after a single METH administration; however, it was altered in the nucleus accumbens. Seven days after multiple METH administrations, TH and TPH activities were decreased in most caudate regions but not in the nucleus accumbens or globus pallidus. These data demonstrate that (1) the effects of METH on TPH and TH vary regionally; and (2) the short-term and long-term regional responses of TPH to METH in the caudate and globus pallidus correlated. In contrast, METH-induced acute TH responses did not predict the long-term changes in TH activity.