An Ep-ICD Based Index Is a Marker of Aggressiveness and Poor Prognosis in Thyroid Carcinoma

Background

Nuclear accumulation of the intracellular domain of epithelial cell adhesion molecule (Ep-ICD) in tumor cells was demonstrated to predict poor prognosis in thyroid carcinoma patients in our earlier study. Here, we investigated the clinical significance of Ep-ICD subcellular localization index (ESLI) in distinguishing aggressive papillary thyroid carcinoma (PTC) from non-aggressive cases.

Methods

Using domain specific antibodies against the intracellular (Ep-ICD) and extracellular (EpEx) domains of epithelial cell adhesion molecule, 200 archived tissues from a new cohort of patients with benign thyroid disease as well as malignant aggressive and non aggressive PTC were analyzed by immunohistochemistry (IHC). ESLI was defined as sum of the IHC scores for accumulation of nuclear and cytoplasmic Ep-ICD and loss of membranous EpEx; ESLI = [Ep-ICD_nuc + Ep-ICD_cyt + loss of membranous EpEx].

Results

For the benign thyroid tissues, non-aggressive PTC and aggressive PTC, the mean ESLI scores were 4.5, 6.7 and 11 respectively. Immunofluorescence double staining confirmed increased nuclear Ep-ICD accumulation and decreased membrane EpEx expression in aggressive PTC. Receiver-operating characteristic (ROC) curve analysis showed an area under the curve (AUC) of 0.841, 70.2% sensitivity and 83.9% specificity for nuclear Ep-ICD for differentiating aggressive PTC from non-aggressive PTC. ESLI distinguished aggressive PTC from non-aggressive cases with improved AUC of 0.924, 88.4% sensitivity and 85.5% specificity. Our study confirms nuclear accumulation of Ep-ICD and loss of membranous EpEx occurs in aggressive PTC underscoring the potential of Ep-ICD and ESLI to serve as diagnostic markers for aggressive PTC. Kaplan Meier survival analysis revealed significantly reduced disease free survival (DFS) for ESLI positive (cutoff >10) PTC (p<0.05), mean DFS = 133 months as compared to 210 months for patients who did not show positive ESLI.

Conclusion

ESLI scoring improves the identification of aggressive PTC and thereby may serve as a useful index for defining aggressiveness and poor prognosis among PTC patients.     

Expression of apoptosis genes in the brain of rats with genetically defined fear-induced aggression

The programmed cell death (or apoptosis) plays an important role both in developing and mature brains. Multiple data indicate the involvement of processes of apoptosis in mechanisms of different psychopathologies. At the same time, nothing is known about the role of apoptosis in the regulation of genetically defined aggression. In the present work, the expression of the genes that encode main pro- and antiapoptotic BAX and BCL-XL proteins, as well as caspase 3 (the main effector of apoptosis), in different brain structures of rats that were selected on a high aggression towards human (or its absence) was studied. A significant increase in the expression of the gene encoding caspase 3 was detected in the hypothalamus. This was accompanied by a significant decrease in the expression of proapoptotic Bax gene in the hippocampus and increase in mRNA level of antiapoptotic Bcl-xl gene in the raphe nuclei area of midbrain in highly aggressive rats. An increase in the ratio Bcl-xl: Bax was found in the midbrain and amygdala; a trend towards an increase in the ratio was also found in hippocampus of aggressive animals compared to tame animals. Thus, we demonstrated that genetically defined fear-induced aggression is associated with significant changes in the genetic control of apoptosis in the brain. It is assumed that an increase in the Bcl-xl gene expression (accompanied by a decrease in the Bax gene expression) can indicate an increase in the threshold of neuronal apoptosis in highly aggressive rats.     

Brain monoamine oxidase in mink selected for their reaction to man]

Monoamineoxidase activity was studied in minks of three behavioural groups--those bred for absence of aggression towards man, those bred for high aggression to man, and those of non-selected population. Breeding for the absence of aggression was accompanied by a decrease of MAO-B activity with unchanged MAO-A activity. The minks bred for aggressive behaviour towards man, as compared to those bred for the absence of aggression, were characterised by increased MAO-A and MAO-B activities in the brain stem. The effect of emotional stress on MAO-A and MAO-B was similar in aggressive, non-aggressive and unselected minks and was expressed in a decrease of both MAO-A and MAO-B activity. The MAO activity of cerebral hemispheres remained unaffected both by selection for behaviour and by the emotional stress.     

A transcriptional network associated with natural variation in Drosophila aggressive behavior

Background  

Aggressive behavior is an important component of fitness in most animals. Aggressive behavior is genetically complex, with natural variation attributable to multiple segregating loci with allelic effects that are sensitive to the physical and social environment. However, we know little about the genes and genetic networks affecting natural variation in aggressive behavior. Populations of Drosophila melanogaster harbor quantitative genetic variation in aggressive behavior, providing an excellent model system for dissecting the genetic basis of naturally occurring variation in aggression.     

Male urine signals social rank in the Mozambique tilapia (Oreochromis mossambicus)

Background  

The urine of freshwater fish species investigated so far acts as a vehicle for reproductive pheromones affecting the behaviour and physiology of the opposite sex. However, the role of urinary pheromones in intra-sexual competition has received less attention. This is particularly relevant in lek-breeding species, such as the Mozambique tilapia (Oreochromis mossambicus), where males establish dominance hierarchies and there is the possibility for chemical communication in the modulation of aggression among males. To investigate whether males use urine during aggressive interactions, we measured urination frequency of dye-injected males during paired interactions between size-matched males. Furthermore, we assessed urinary volume stored in the bladder of males in a stable social hierarchy and the olfactory potency of their urine by recording of the electro-olfactogram.     

Association of dopamine‐ and serotonin‐related genes with canine aggression

Human‐directed canine aggression was studied using 50 aggressive and 81 non‐aggressive dogs. We examined 62 single nucleotide polymorphisms (SNPs) occurring in or in the close vicinity of 16 neurotransmitter‐related genes. Allelic associations with aggression were identified for DRD1, HTR1D, HTR2C and SLC6A1. Risk or protective haplotypes for aggressive behaviour based on 2–5 SNPs were identified. The frequency of aggressive dogs varied significantly between the haplotypes within loci and the odds ratios of aggression in dogs with risk haplotypes compared with protective haplotypes varied from 4.4 (HTR2C) to 9.0 (SLC6A1). A risk haplotype across the neurotransmitter receptor gene HTR1D harboured a non‐synonymous SNP with a potential effect on protein function. We identified no haplotypes in complete association with the recorded phenotypes, supporting a complex inheritance of aggression.     

Biogenic amines in the ponerine ant Harpegnathos saltator: serotonin and dopamine immunoreactivity in the brain

Many studies suggest a role for biogenic amines in a variety of insect behaviors including intraspecific aggression. In ants, despite a rich behavioral repertoire and prominent aggressive interactions, little is known about the potential impact of biogenic amines. This may partly be due to the general lack of information about aminergic systems in the ant brain. The present study investigates serotonergic and dopaminergic neuronal systems in the brain of the ponerine ant Harpegnathos saltator. In H. saltator, intraspecific aggression is important for the regulation of reproduction. This species, therefore, is amenable to comparative studies of aminergic neuronal effects on long-term changes in aggression. Using immunocytochemistry and confocal microscopy, we found that in the brains of sterile workers, the distributions of serotonergic and dopaminergic neuronal processes differed substantially. In addition, branching patterns of serotonergic neurons showed marked differences between males and females. Brains of workers after 3 days and 3 weeks of aggressive interactions revealed no marked differences in serotonergic and dopaminergic neurons compared to those of reproductive and non-aggressive individuals. We conclude that different levels of intraspecific aggression do not involve profound anatomical changes in serotonergic and dopaminergic neurons. Subtle changes may be masked by inter-individual variances.     

Impact of gasoline inhalation on some neurobehavioural characteristics of male rats

Background  

This paper examines closely and compares the potential hazards of inhalation of two types of gasoline (car fuel). The first type is the commonly use leaded gasoline and the second is the unleaded type enriched with oxygenate additives as lead substituent in order to raise the octane number. The impacts of gasoline exposure on Na⁺, K⁺-ATPase, superoxide dismutase (SOD), acetylcholinesterase (AChE), total protein, reduced glutathione (GSH), and lipid peroxidation (TBARS) in the cerebral cortex, and monoamine neurotransmitters dopamine (DA), norepinephrine (NE) and serotonin (5-HT) in the cerebral cortex, hippocampus, cerebellum and hypothalamus were evaluated. The effect of gasoline exposure on the aggressive behaviour tests was also studied.     

Piglet- and stockperson-directed sow aggression after farrowing and the relationship with a pre-farrowing,human approach test

The aims of the experiment were to determine the incidence and severity of piglet- and stockperson-directed aggression in two different farrowing systems and to determine whether either could be predicted using behavioural and physiological measures recorded previously during a standard human approach test. Sixty-two gilts, permanently housed in groups of 4–5, were approach tested at 6–8 weeks prior to parturition. Gilts were moved to a handling area, fitted with a heart rate monitor and moved to a square test arena. After 2 min familiarisation, an unfamiliar human entered the pen and stood for 3 min against one wall. Then, the human approached the gilt and touched her snout. Behaviour and heart rate were recorded continuously. Social rank was determined for each gilt using pair-wise food competition tests. At farrowing, gilts were randomly assigned to either open pens or conventional crates. At parturition, litter size and piglet weights were recorded and causes of any deaths ascertained, with emphasis on those piglets dying due to savaging. The aggression directed at the stockperson during piglet weighing at birth, 7 days and 14 days of age was scored on a scale of 1–5 (non-aggressive to extremely aggressive). Five gilts savaged their piglets and five other gilts were particularly aggressive towards the stockperson. Savaging of piglets and levels of stockperson-directed aggression were higher in the open pen system than in farrowing crates. Gilts that savaged piglets were more likely to show ‘shy’ behaviour during the human approach test, whereas gilts that were highly aggressive towards the stockperson were more likely to show ‘bold’ behaviour in the same test. Stockperson-directed aggression was displayed consistently, both within the same lactation and between subsequent lactations. Stockperson-directed aggression was unrelated to piglet survival but did confer advantages in piglet growth rate between birth and 7 days of age.     

Modifications of serotonergic and adrenergic receptor concentrations in the brain of aggressive Canis familiaris

The aim of the study was to measure beta-adrenergic (beta-AR) and serotonergic (5-HTR) receptor concentrations in different brain areas (frontal cortex, hippocampus, hypothalamus and thalamus) of normal and aggressive dogs. Eight adult male dogs, 4.2+/-0.6 years old, showing no clinical signs but aggression, were used for the study. Eight healthy male dogs, 4.4+/-0.8 years old, with no history of neurological and/or behavioural disorders and accidental death, were used as controls. The whole frontal cortex, hippocampus, thalamus and hypothalamus were collected after euthanasia and plasma membrane fractions obtained by ultracentrifugation. beta-AR and 5-HTR were measured by binding assays using specific radioligand [(-)[3H]CGP 12177 and 5-hydroxy[3H]-tryptamine trifluoroacetate, respectively]. A significant decrease in beta-AR levels was observed in the frontal cortex (P=0.001), hippocampus (P<0.0001), and thalamus (P<0.0001) of aggressive dogs compared to controls. As far as 5-HTR are concerned, two receptor subtypes were detected. The two subtypes were classified as low-affinity (5-HTR LA) and high-affinity (5-HTR HA) serotonergic receptors for [3H]-hydroxytryptamine, on the basis of their affinity for [3H]-hydroxytryptamine. 5-HTR LA significantly increased in the whole central nervous system (CNS) area of aggressive dogs (frontal cortex P=0.071; hippocampus P=0.0013; thalamus P<0.0001; hypothalamus P=0.0004); 5-HTR HA significantly increased only in the thalamus (P=0.0005) and hypothalamus (P=0.0002). Results suggest the possible role played by the catecholaminergic and serotonergic systems in canine aggressive behaviour. The understanding of the biological basis of canine aggression may enable the development of pharmacological treatments that would target specific neurotransmitter systems.     

Extensive Reorganization of Behavior Accompanies Ontogeny of Aggression in Male Flesh Flies

Aggression, costly in both time and energy, is often expressed by male animals in defense of valuable resources such as food or potential mates. Here we present a new insect model system for the study of aggression, the male flesh fly Sarcophaga crassipalpis, and ask whether there is an ontogeny of aggression that coincides with reproductive maturity. After establishing that reproductive maturity occurs by day 3 of age (post-eclosion), we examined the behavior of socially isolated males from different age cohorts (days 1, 2, 3, 4, and 6) upon introduction, in a test arena, with another male of the same age. The results show a pronounced development of aggression with age. The change from relative indifference to heightened aggression involves a profound increase in the frequency of high-intensity aggressive behaviors between days 1 and 3. Also noteworthy is an abrupt increase in the number of statistically significant transitions involving these full-contact agonistic behaviors on day 2. This elevated activity is trimmed back somewhat by day 3 and appears to maintain a stable plateau thereafter. No convincing evidence was found for escalation of aggression nor the establishment of a dominance relationship over the duration of the encounters. Despite the fact that aggressive interactions are brief, lasting only a few seconds, a major reorganization in the relative proportions of four major non-aggressive behaviors (accounting for at least 96% of the total observation time for each age cohort) accompanies the switch from low to high aggression. A series of control experiments, with single flies in the test arenas, indicates that these changes occur in the absence of the performance of aggressive behaviors. This parallel ontogeny of aggressive and non-aggressive behaviors has implications for understanding how the entire behavioral repertoire may be organized and reorganized to accommodate the needs of the organism.     

Mutations in many genes affect aggressive behavior in Drosophila melanogaster

Background  

Aggressive behavior in animals is important for survival and reproduction. Identifying the underlying genes and environmental contexts that affect aggressive behavior is important for understanding the evolutionary forces that maintain variation for aggressive behavior in natural populations, and to develop therapeutic interventions to modulate extreme levels of aggressive behavior in humans. While the role of neurotransmitters and a few other molecules in mediating and modulating levels of aggression is well established, it is likely that many additional genetic pathways remain undiscovered. Drosophila melanogaster has recently been established as an excellent model organism for studying the genetic basis of aggressive behavior. Here, we present the results of a screen of 170 Drosophila P-element insertional mutations for quantitative differences in aggressive behavior from their co-isogenic control line.     

Oral malignant melanomas and other head and neck neoplasms in Danish dogs - data from the Danish Veterinary Cancer Registry

Background  

Head and neck cancers (HNC) are relatively common and often very serious diseases in both dogs and humans. Neoplasms originating in the head and neck region are a heterogeneous group. HNC often has an unfavourable prognosis and the proximity of the tissue structures renders extirpation of tumours with sufficient margins almost incompatible with preservation of functionality. In humans oral malignant melanoma (OMM) is extremely rare, but represents a particular challenge since it is highly aggressive as is the canine counterpart, which thus may be of interest as a spontaneous animal model.     

A note on the effectiveness of behavioural rehabilitation for reducing inter-dog aggression in shelter dogs

The effectiveness of a rehabilitation program for reducing inter-dog aggression was evaluated at the municipal animal shelter. Sixteen dogs (of 60 examined) met the study criteria of medium inter-dog aggression as determined by an inter-dog aggression test. These dogs received a 10-day treatment of daily rehabilitation for 30 min (rehabilitation group, n = 9) or daily release into an outdoor enclosure for 30 min (control group, n = 7). Rehabilitation consisted of desensitising and counter-conditioning dogs to the approach of other “stimulus” dogs. Most dogs in the rehabilitation group showed a decline in aggression scores when re-tested after the last treatment (day 11), and differed significantly from the control dogs which showed either an increase or no change in aggression scores (U = 8.5, P < 0.01). Rehabilitation dogs also showed lower frequencies of aggressive body postures (“facing the stimulus dog”, P < 0.05, and “stiff posture”, P < 0.10) and higher frequencies of less assertive postures (“ears back”, P < 0.05, and “lowered neck”, P < 0.10) on day 11. The differences between groups were no longer significant when a reduced sample of dogs was tested 1 week after rehabilitation ended (day 18). The study shows short-term reduction of inter-dog aggression through rehabilitation, but further work is needed on effective ways of maintaining the behavioural change.     

Contexts and predictability of aggression in chimpanzees

Reasons for aggression may be deduced from the situations preceding aggressive behaviour. This we may call the retrospective approach. In addition to results from this conventional procedure the present paper investigates the predictability of aggressive behaviour. In this so-called anticipatory approach, particular non-agonistic events were used as predictors of aggression. These events had in common that they were intuitively judged to be unpleasant for one of the chimpanzees. This individual was observed during the next 10 min in order to establish if its inclination to exhibit aggression had increased shortly after that seemingly frustrating event. The studies reported here were carried out on a colony of 20 semi-free-living chimpanzees Pan troglodytes in Arnhem Zoo. The data show that: (1) half of all aggressive actions arose in agonistic context: thus aggression was contagious; (2) adult males performed apparent spontaneous aggression remarkably often: this result is suggested to reflect dominance-rivalry among males; (3) aggressive behaviour was predictable on the basis of intuition, but attempts to account for the observer's intuitive knowledge were not entirely successful.     

Influence of aggressive computer games on the brain cortex activity level in adolescents

Dynamic changes in the activities of different areas of the brain cortex were studied in order to determine cortical structures responsible for playing aggressive computer games, with the degree of initial aggression of the adolescent subjects taken into account. Changes in anxiety and aggression produced by aggressive computer games were found to depend on the initial level of aggression of the subjects. In adolescents with a high baseline level of aggression, the amplitude of the N200 component increased in the frontal and decreased in the temporal areas of the cortex, whereas, in adolescents with a low baseline aggression level, N200 decreased in the frontal and increased in the temporal cortical areas.     

Juvenile hormone levels are increased in winners of cockroach fights

In lobster cockroach (Nauphoeta cinerea) adult males, concomitant expression of attack behavior and an increase in juvenile hormone (JH) III titer can be induced by contact with an isolated antenna [Chou et al., 2007. Antenna contact and agonism in the male lobster cockroach, Nauphoeta cinerea. Horm. Behav. 52, 252–260]. In the present study, socially naïve N. cinerea males that were either aggressive posture-adopting (i.e., “ready-for-fight”) or not (i.e., “non-ready-for-fight”) were paired to ask if status was determined by JH III levels before the encounter and if JH III levels were altered in dominants and subordinates after the encounter. The results showed that, although in the non-aggressive posture-adopting male pairs, the one with higher JH titers before the encounter was more likely to become the dominant, this was not the case in pairs formed between aggressive posture-adopting males or between non-aggressive posture-adopting and aggressive posture-adopting males. In all types of male pairs combined, JH III levels in the dominant were significantly increased after the encounter compared with before the encounter and were significantly higher than those in the subordinates, suggesting that the JH III increase in the dominants may serve to sustain aggression. JH III application before rank formation had a significant effect on establishment of dominant status in non-aggressive posture-adopting, but not aggressive posture-adopting, males. After rank formation, JH III application to subordinates had no effect on rank switch. These results indicate that the relationship between JH and aggression in this cockroach species is broadly consistent with the vertebrate challenge hypothesis, which predicts that testosterone levels increase in response to social stimuli to modulate aggression.     

Effect of the stage of the reproductive cycle on vocalization and behaviour in female bank voles

Females of several species of rodents are known to emit audible and ultrasonic sounds during same-sex encounters. There is very little information about factors affecting this vocalization. The present study was undertaken to investigate the effect of the stage of the reproductive cycle on vocalization and behaviour of adult bank vole females during various same-sex encounters. Pregnancy and lactation were studied as important phases of female life. The possible role of ovarian hormones in the emission of acoustic signals was also investigated as these hormones are known to be important in the regulation of other female social behaviour. The behaviour and vocalization of sexually naive, ovariectomized, pregnant and lactating females were studied using 10-min confrontation tests. The results demonstrate that the behaviour displayed and the emission of sounds in female–female bank vole encounters depend on the phase of reproductive cycle. Ultrasounds are produced more often by sexually naive and ovariectomized females which present mainly non-aggressive behaviour than by more aggressive lactating females. Audible sounds are emitted only occasionally by naive and by ovariectomized females but pregnant and especially lactating females emitted such calls more often, with shorter latencies and for longer than the unmated groups. Ultrasonic vocalization therefore seems to be related to non-aggressive behaviour and audible vocalization to aggression.