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The Aurora kinase family comprises three serine/threonine kinases, Aurora-A, -B and -C. Among these, Aurora-A and -B play central roles in mitosis, whereas Aurora-C executes unique roles in meiosis. Overexpression or gene amplification of Aurora kinases have been reported in a broad range of human malignancies, pointing to their role as potent oncogenes in tumorigenesis.Aurora kinases therefore represent promising targets for anticancer therapeutics. So far, a number of Aurora kinase inhibitors (AKIs) have been generated, of which some are currently undergoing clinical trials. Recent studies have unveiled novel unexpected functions of Aurora kinases during cancer development and the mechanisms underlying the anticancer actions of AKIs. In this review, we discuss the most recent advances in Aurora-A kinase research and targeted cancer therapy, focusing on the oncogenic roles and signaling pathways of Aurora-A kinases in contributing tumorigenesis, the recent preclinical and clinical AKI data and potential alternative routes for Aurora-A kinase inhibition.Key words: Aurora-A; Aurora kinase inhibitors (AKIs); targeted cancer therapy; mitosis; tumorigenesis 3 In mammals, the Aurora family of serine/threonine kinases consists of Aurora-A, -B and -C, which share a highly conserved catalytic domain containing auto-phosphorylating sites. The catalytic domain is flanked by a very short C-terminal tail and an N-terminal domain of variable lengths 1,2 . In the C-terminal regions of Auroras, there exists a short amino-acid peptide motif called "destruction box" (D-box). The D-box is recognized by the anaphase-promoting complex/cyclosome (APC/C) for degradation through the ubiquitin/proteasome-dependent pathway ( Fig. 1A). Despite their structural similarities, the expression patterns, cellular localization and physiological functions of these three Aurora kinases are largely distinct.Aurora-A and -B are commonly expressed in most cell types whereas Aurora-C is specially expressed in the testis. Both Aurora-A and -B play key roles in regulating cell-cycle progression from G2 through to cytokinesis. Aurora-C has a unique physiological role in spermatogenesis and functions as a chromosomal passenger protein similar to Aurora-B in mitosis 2 .Overexpression of Aurora-A and -B have been found in multiple types of cancer (Table 1), which function as oncogenes to promote tumorigenesis, providing potential targets for cancer therapy.However, comparatively little information is available regarding the roles of Aurora-C in cancer.In this review, we will focus on recent progress as well as the main unresolved issues associated with Aurora-A in cancer.4 1 FUNCTIONS OF AURORA-A In normal cells a. MitosisIn G1 phase, the level of Aurora-A is rarely detectable. During S phase, a small proportion of Aurora-A is first detected at centrosomes. At late G2 phase, Aurora-A accumulates evidently at centrosomes and becomes activated 3 . During prometaphase and metaphase, active Aurora-A localizes on bipolar spindles and spindle poles after...

Extinction therapy has been suggested to suppress the conditioned motivational effect of drug cues to prevent relapse. However, extinction forms a new inhibiting memory rather than erasing the original memory trace and drug memories invariably return. Perineuronal nets (PNNs) are a specialized extracellular matrix around interneurons in the brain that have been suggested to be a permissive factor that allows synaptic plasticity in the adolescent brain. The degradation of PNNs caused by chondroitinase ABC (ChABC) may generate induced juvenile-like plasticity (iPlasticity) and promote experience-dependent plasticity in the adult brain. In the present study, we investigated the effect of removing PNNs in the amygdala of rat on the extinction of drug memories. We found that extinction combined with intra-amygdala injections of ChABC (0.01 U/side) prevented the subsequent priming-induced reinstatement of morphine-induced and cocaine-induced, but not food -induced, conditioned place preference (CPP). Intra-amygdala injections of ChABC alone had no effect on the retention, retrieval, or relearning of morphine-induced CPP and storage of acquired food-induced CPP. Moreover, we found that the procedure facilitated the extinction of heroin-and cocaine-seeking behavior and prevented the spontaneous recovery and druginduced reinstatement of heroin-and cocaine-seeking behavior. We also found that the effect of PNNs degradation combined with extinction may be mediated by the potentiation of several plasticity-related proteins in the amygdala. Altogether, our findings demonstrate that a combination of extinction training with PNNs degradation in the amygdala erases drug memories and suggest that ChABC may be an attractive candidate for the prevention of relapse.

RationaleThe majority of drug abusers are incapable of sustaining abstinence over any length of time. Accumulating evidence has linked intense and involuntary craving, Impulsive decision-making and mood disturbances to risk for relapse. However, little is known about temporal changes of these neuropsychological functions in methamphetamine (METH)-dependent individuals.ObjectivesTo investigate the effect of length of abstinence on decision-making, craving (baseline and cue-induced), and emotional state in METH-addicted individuals.MethodsIn this cross-sectional study, 183 adult METH-dependent patients at an addiction rehabilitation center who were abstinent for 6 days (n = 37), 14 days (n = 33), 1 month (n = 31), 3 months (n = 30), 6 months (n = 26), or 1 year (n = 30) and 39 healthy subjects were administered the Iowa Gambling Task (IGT) to assess decision-making performance. Depression, anxiety, and impulsivity were also examined. One hundred thirty-nine METH abusers who were abstinent for the aforementioned times then underwent a cue session, and subjective and physiological measures were assessed.ResultsMETH dependent individuals who were abstinent for longer periods of time exhibited better decision-making than those who were abstinent for shorter periods of time. And self-reported emotional symptoms improved with abstinence. METH abusers’ ratings of craving decreased with the duration of abstinence, while cue-induced craving increased until 3 months of abstinence and decreased at 6 months and 1 year of abstinence.ConclusionsWe present time-dependent alterations in decision-making, emotional state, and the incubation of cue-induced craving in METH-dependent individuals, which might have significant clinical implications for the prevention of relapse.

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Background Morinda officinalis oligosaccharides have been reported to exert neuroprotective and antidepressant-like effects in the forced swim test in mice. However, the mechanisms that underlie the antidepressant-like effects of Morinda officinalis oligosaccharides are unclear.MethodsChronic unpredictable stress and forced swim test were used to explore the antidepressant-like effects of Morinda officinalis oligosaccharides and resilience to stress in rats. The phosphoinositide-3 kinase inhibitor LY294002 was microinjected in the medial prefrontal cortex to explore the role of glycogen synthase kinase-3β in the antidepressant-like effects of Morinda officinalis oligosaccharides. The expression of brain-derived neurotrophic factor, phosphorylated-Ser9-glycogen synthase kinase 3β, β-catenin, and synaptic proteins was determined in the medial prefrontal cortex and the orbitofrontal cortex by western blot.ResultsWe found that Morinda officinalis oligosaccharides effectively ameliorated chronic unpredictable stress-induced depression-like behaviors in the sucrose preference test and forced swim test. The Morinda officinalis oligosaccharides also significantly rescued chronic unpredictable stress-induced abnormalities in the brain-derived neurotrophic factor-glycogen synthase kinase-3β-β-catenin pathway and synaptic protein deficits in the medial prefrontal cortex but not orbitofrontal cortex. The activation of glycogen synthase kinase-3β by the phosphoinositide-3 kinase inhibitor LY294002 abolished the antidepressant-like effects of Morinda officinalis oligosaccharides in the forced swim test. Naïve rats that were treated with Morinda officinalis oligosaccharides exhibited resilience to chronic unpredictable stress, accompanied by increases in the expression of brain-derived neurotrophic factor, phosphorylated-Ser9-glycogen synthase kinase-3β, and β-catenin in the medial prefrontal cortex.ConclusionOur findings indicate that the brain-derived neurotrophic factor-glycogen synthase kinase-3β-β-catenin pathway in the medial prefrontal cortex may underlie the antidepressant-like effect of Morinda officinalis oligosaccharides and resilience to stress.

The ephrin B2 (EphB2) receptor is a tyrosine kinase receptor that is associated with synaptic development and maturation. It has recently been implicated in cognitive deficits and anxiety. However, still unknown is the involvement of EphB2 in the vulnerability to stress. In the present study, we observed decreases in EphB2 levels and their downstream molecules in the medial prefrontal cortex (mPFC) but not in the orbitofrontal cortex (OFC) in mice that were susceptible to chronic social defeat stress. The activation of EphB2 receptors with EphrinB1-Fc in the mPFC produced stress-resistant and antidepressant-like behavioral effects in susceptible mice that lasted for at least 10 days. EphB2 receptor knockdown by short-hairpin RNA in the mPFC increased the susceptibility to stress and induced depressive-like behaviors in a subthreshold chronic social defeat stress paradigm. These behavioral effects were associated with changes in the phosphorylation of cofilin and membrane α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) trafficking and the expression of some synaptic proteins in the mPFC. We also found that EphB2 regulated stress-induced spine remodeling in the mPFC. Altogether, these results indicate that EphB2 is a critical regulator of stress vulnerability and might be a potential target for the treatment of depression.