Nerve injury triggers time-dependent activation of the locus coeruleus, influencing spontaneous pain-like behavior in rats

BACKGROUND

Dynamic changes in neuronal activity and in noradrenergic locus coeruleus (LC) projections have been proposed during the transition from acute to chronic pain. Thus, we explored the cellular cFos activity of the LC and its projections, in conjunction with spontaneous pain-like behavior in neuropathic rats.

METHODS

Tyrosine hydroxylase:Cre and wild-type Long-Evans rats, males and females, were subjected to chronic constriction injury (CCI) for 2 (short-term, CCI-ST) or 30 days (long-term, CCI-LT), evaluating cFos and Fluoro-Gold expression in the LC, and its projections to the spinal cord (SC) and rostral anterior cingulate cortex (rACC). These tests were carried out under basal conditions (unstimulated) and following noxious mechanical stimulation. LC activity was evaluated through chemogenetic and pharmacological approaches, as were its projections, in association with spontaneous pain-like behaviors.

RESULTS

CCI-ST enhanced basal cFos expression in the LC and in its projection to the SC, which increased further after noxious stimulation. Similar basal activation was found in the neurons projecting to the rACC, although this was not modified by stimulation. Strong basal cFos expression was found in CCI-LT, specifically in the projection to the rACC, which was again not modified by stimulation. No cFos expression was found in the CCI-LT LCipsi/contra→SC. Chemogenetics showed that CCI-ST is associated with greater spontaneous pain-like behavior when the LCipsi is blocked, or by selectively blocking the LCipsi→SC projection. Activation of the LCipsi or LCipsi/contra→SC dampened pain-like behavior. Moreover, DREADDs-mediated inactivation of the CCI-ST LCipsi→rACC or CCI-LT LCipsi/contra→rACC pathway, or intra-rACC antagonism of alpha-adrenoreceptors, also dampens pain-like behavior.

CONCLUSIONS

In the short term, activation of the LC following CCI attenuates spontaneous pain-like behaviors via projections to the SC while increases nociception via projections to the rACC. In the long term, only the projections from the LC to the rACC contribute to modulate pain-like behaviors in this model.

Inflammatory bowel disease induces pathological α-synuclein aggregation in the human gut and brain

AIMS

According to Braak's hypothesis, it is plausible that Parkinson's disease (PD) originates in the enteric nervous system (ENS) and spreads to the brain through the vagus nerve. In this work, we studied whether inflammatory bowel diseases (IBDs) in humans can progress with the emergence of pathogenic α-synuclein (α-syn) in the gastrointestinal tract and midbrain dopaminergic neurons.

METHODS

We have analysed the gut and the ventral midbrain from subjects previously diagnosed with IBD and form a DSS-based rat model of gut inflammation in terms of α-syn pathology.

RESULTS

Our data support the existence of pathogenic α-syn in both the gut and the brain, thus reinforcing the potential role of the ENS as a contributing factor in PD aetiology. Additionally, we have analysed the effect of a DSS-based rat model of gut inflammation to demonstrate (i) the appearance of P-α-syn inclusions in both Auerbach's and Meissner's plexuses (gut), (ii) an increase in α-syn expression in the ventral mesencephalon (brain) and (iii) the degeneration of nigral dopaminergic neurons, which all are considered classical hallmarks in PD.

CONCLUSION

These results strongly support the plausibility of Braak's hypothesis and emphasise the significance of peripheral inflammation and the gut-brain axis in initiating α-syn aggregation and transport to the substantia nigra, resulting in neurodegeneration.

Caecum OX40+CD4 T-cell subset associates with mucosal damage and key markers of disease in treated HIV-infection

BACKGROUND

Blood OX40-expressing CD4 T-cells from antiretroviral (ART)-treated people living with HIV (PWH) were found to be enriched for clonally-expanded HIV sequences, hence contributing to the HIV reservoir. OX40-OX40L is also a checkpoint regulator of inflammation in multiple diseases. We explored gut mucosal OX40+CD4+ T-cells and their potential significance in HIV disease.

METHODS

Biopsies of caecum and terminal-ileum of ART-treated PWH (n = 32) were obtained and mucosal damage and HIV reservoir were assessed. Mucosal OX40+ and Ki67+ CD4 T-cell subsets, as well as several tissue T-cell subsets modulating mucosal integrity and homeostasis (Th17, Th22, Treg, Tc17, Tc22, IL17+TCRγδ, IL22+TCRγδ) were quantified. Inflammatory-related markers, T-cell activation and thymic output were also determined in blood samples. Correlations were explored using Spearman rank test and corrected for multiple comparisons by Benjamini-Hochberg.

RESULTS

Compared to healthy controls, a high frequency of mucosal, mainly caecum, CD4 T-cells were OX40+ in PWH. Such frequency strongly correlated with nadir CD4 (r = -0.836; p < 0.0001), CD4/CD8 ratio (r = -0.630; p = 0.002), caecum mucosal damage (r = 0.606; p = 0.008), caecum Th22 (r = -0.635; p = 0.002), caecum Th17 (r = 0.474; p = 0.03) and thymic output (r = -0.686; p < 0.001). It also correlated with Neutrophil-to-Lymphocyte Ratio and blood CD4 T-cell activation and tended to with mucosal HIV reservoir.

CONCLUSION

High frequencies of caecum OX40+CD4 T-cells are found in people with HIV (PWH) and successful viral control. Interestingly, this cellular subset reflects key markers of disease and peripheral T-cell activation, as well as HIV-driven mucosal damage. OX40+CD4 T-cells deserve further investigation since they could expand because of T-cell homeostatic proliferation and relate to the Th22/Th17 gut mucosal ratio.

Preeclampsia and risk of maternal pulmonary hypertension at high altitude in Bolivia

Women with a history of preeclampsia (PE) have a greater risk of pulmonary arterial hypertension (PAH). In turn, pregnancy at high altitude is a risk factor for PE. However, whether women who develop PE during highland pregnancy are at risk of PAH before and after birth has not been investigated. We tested the hypothesis that during highland pregnancy, women who develop PE are at greater risk of PAH compared to women undergoing healthy highland pregnancies. The study was on 140 women in La Paz, Bolivia (3640m). Women undergoing healthy highland pregnancy were controls (C, n = 70; 29 ± 3.3 years old, mean±SD). Women diagnosed with PE were the experimental group (PE, n = 70, 31 ± 2 years old). Conventional (B- and M-mode, PW Doppler) and modern (pulsed wave tissue Doppler imaging) ultrasound were applied for cardiovascular íííassessment. Spirometry determined maternal lung function. Assessments occurred at 35 ± 4 weeks of pregnancy and 6 ± 0.3 weeks after birth. Relative to highland controls, highland PE women had enlarged right ventricular (RV) and right atrial chamber sizes, greater pulmonary artery dimensions and increased estimated RV contractility, pulmonary artery pressure and pulmonary vascular resistance. Highland PE women had lower values for peripheral oxygen saturation, forced expiratory flow and the bronchial permeability index. Differences remained 6 weeks after birth. Therefore, women who develop PE at high altitude are at greater risk of PAH before and long after birth. Hence, women with a history of PE at high altitude have an increased cardiovascular risk that transcends the systemic circulation to include the pulmonary vascular bed.

A metagenome-wide association study of HIV disease progression in HIV controllers

Some HIV controllers experience immunologic progression with CD4⁺ T cell decline. We aimed to identify genetic factors associated with CD4⁺ T cell lost in HIV controllers. A total of 561 HIV controllers were included, 442 and 119 from the International HIV controllers Study Cohort and the Swiss HIV Cohort Study, respectively. No SNP or gene was associated with the long-term non-progressor HIV spontaneous control phenotype in the individual GWAS or in the meta-analysis. However, SNPs previously associated with natural HIV control linked to HLA-B (rs2395029 [p = 0.005; OR = 1.70], rs59440261 [p = 0.003; OR = 1.78]), MICA (rs112243036 [p = 0.011; OR = 1.45]), and PSORS1C1 loci (rs3815087 [p = 0.017; OR = 1.39]) showed nominal association with this phenotype. Genetic factors associated with the long-term HIV controllers without risk of immunologic progression are those previously related to the overall HIV controller phenotype.

Microglial Caspase-3 is essential for modulating hippocampal neurogenesis

Adult hippocampal neurogenesis (AHN) is a process involved in numerous neurodegenerative diseases. Many researchers have described microglia as a key component in regulating the formation and migration of new neurons along the rostral migratory stream. Caspase-3 is a cysteine-aspartate-protease classically considered as one of the main effector caspases in the cell death program process. In addition to this classical function, we have identified the role of this protein as a modulator of microglial function; however, its action on neurogenic processes is unknown. The aim of the present study is to identify the role of Caspase-3 in neurogenesis-related microglial functions. To address this study, Caspase-3 conditional knockout mice in the microglia cell line were used. Using this tool, we wanted to elucidate the role of this protein in microglial function in the hippocampus, the main region in which adult neurogenesis takes place. After the reduction of Caspase-3 in microglia, mutant mice showed a reduction of microglia in the hippocampus, especially in the dentate gyrus region, a region inherently associated to neurogenesis. In addition, we found a reduction in doublecortin-positive neurons in conditional Caspase-3 knockout mice, which corresponds to a reduction in neurogenic neurons. Furthermore, using high-resolution image analysis, we also observed a reduction in the phagocytic capacity of microglia lacking Caspase-3. Behavioral analysis using object recognition and Y-maze tests showed altered memory and learning in the absence of Caspase-3. Finally, we identified specific microglia located specifically in neurogenic niche positive for Galectin 3 which colocalized with Cleaved-Caspase-3 in control mice. Taken together, these results showed the essential role of Caspase-3 in microglial function and highlight the relevant role of this specific microglial phenotype in the maintenance of AHN in the hippocampus.

Galectin-3 shapes toxic alpha-synuclein strains in Parkinson's disease

Parkinson's Disease (PD) is a neurodegenerative and progressive disorder characterised by intracytoplasmic inclusions called Lewy bodies (LB) and degeneration of dopaminergic neurons in the substantia nigra (SN). Aggregated α-synuclein (αSYN) is known to be the main component of the LB. It has also been reported to interact with several proteins and organelles. Galectin-3 (GAL3) is known to have a detrimental function in neurodegenerative diseases. It is a galactose-binding protein without known catalytic activity and is expressed mainly by activated microglial cells in the central nervous system (CNS). GAL3 has been previously found in the outer layer of the LB in post-mortem brains. However, the role of GAL3 in PD is yet to be elucidated. In post-mortem samples, we identified an association between GAL3 and LB in all the PD subjects studied. GAL3 was linked to less αSYN in the LB outer layer and other αSYN deposits, including pale bodies. GAL3 was also associated with disrupted lysosomes. In vitro studies demonstrate that exogenous recombinant Gal3 is internalised by neuronal cell lines and primary neurons where it interacts with endogenous αSyn fibrils. In addition, aggregation experiments show that Gal3 affects spatial propagation and the stability of pre-formed αSyn fibrils resulting in short, amorphous toxic strains. To further investigate these observations in vivo, we take advantage of WT and Gal3KO mice subjected to intranigral injection of adenovirus overexpressing human αSyn as a PD model. In line with our in vitro studies, under these conditions, genetic deletion of GAL3 leads to increased intracellular αSyn accumulation within dopaminergic neurons and remarkably preserved dopaminergic integrity and motor function. Overall, our data suggest a prominent role for GAL3 in the aggregation process of αSYN and LB formation, leading to the production of short species to the detriment of larger strains which triggers neuronal degeneration in a mouse model of PD.

ARG1-expressing microglia show a distinct molecular signature and modulate postnatal development and function of the mouse brain

Molecular diversity of microglia, the resident immune cells in the CNS, is reported. Whether microglial subsets characterized by the expression of specific proteins constitute subtypes with distinct functions has not been fully elucidated. Here we describe a microglial subtype expressing the enzyme arginase-1 (ARG1; that is, ARG1⁺ microglia) that is found predominantly in the basal forebrain and ventral striatum during early postnatal mouse development. ARG1⁺ microglia are enriched in phagocytic inclusions and exhibit a distinct molecular signature, including upregulation of genes such as Apoe, Clec7a, Igf1, Lgals3 and Mgl2, compared to ARG1^- microglia. Microglial-specific knockdown of Arg1 results in deficient cholinergic innervation and impaired dendritic spine maturation in the hippocampus where cholinergic neurons project, which in turn results in impaired long-term potentiation and cognitive behavioral deficiencies in female mice. Our results expand on microglia diversity and provide insights into microglia subtype-specific functions.

Targeting galectin-3 to counteract spike-phase uncoupling of fast-spiking interneurons to gamma oscillations in Alzheimer's disease

BACKGROUND

Alzheimer's disease (AD) is a progressive multifaceted neurodegenerative disorder for which no disease-modifying treatment exists. Neuroinflammation is central to the pathology progression, with evidence suggesting that microglia-released galectin-3 (gal3) plays a pivotal role by amplifying neuroinflammation in AD. However, the possible involvement of gal3 in the disruption of neuronal network oscillations typical of AD remains unknown.

METHODS

Here, we investigated the functional implications of gal3 signaling on experimentally induced gamma oscillations ex vivo (20-80 Hz) by performing electrophysiological recordings in the hippocampal CA3 area of wild-type (WT) mice and of the 5×FAD mouse model of AD. In addition, the recorded slices from WT mice under acute gal3 application were analyzed with RT-qPCR to detect expression of some neuroinflammation-related genes, and amyloid-β (Aβ) plaque load was quantified by immunostaining in the CA3 area of 6-month-old 5×FAD mice with or without Gal3 knockout (KO).

RESULTS

Gal3 application decreased gamma oscillation power and rhythmicity in an activity-dependent manner, which was accompanied by impairment of cellular dynamics in fast-spiking interneurons (FSNs) and pyramidal cells. We found that the gal3-induced disruption was mediated by the gal3 carbohydrate-recognition domain and prevented by the gal3 inhibitor TD139, which also prevented Aβ42-induced degradation of gamma oscillations. Furthermore, the 5×FAD mice lacking gal3 (5×FAD-Gal3KO) exhibited WT-like gamma network dynamics and decreased Aβ plaque load.

CONCLUSIONS

We report for the first time that gal3 impairs neuronal network dynamics by spike-phase uncoupling of FSNs, inducing a network performance collapse. Moreover, our findings suggest gal3 inhibition as a potential therapeutic strategy to counteract the neuronal network instability typical of AD and other neurological disorders encompassing neuroinflammation and cognitive decline.

The HERC proteins and the nervous system

The HERC protein family is one of three subfamilies of Homologous to E6AP C-terminus (HECT) E3 ubiquitin ligases. Six HERC genes have been described in humans, two of which encode Large HERC proteins -HERC1 and HERC2- with molecular weights above 520 kDa that are constitutively expressed in the brain. There is a large body of evidence that mutations in these Large HERC genes produce clinical syndromes in which key neurodevelopmental events are altered, resulting in intellectual disability and other neurological disorders like epileptic seizures, dementia and/or signs of autism. In line with these consequences in humans, two mice carrying mutations in the Large HERC genes have been studied quite intensely: the tambaleante mutant for Herc1 and the Herc2^+/530 mutant for Herc2. In both these mutant mice there are clear signs that autophagy is dysregulated, eliciting cerebellar Purkinje cell death and impairing motor control. The tambaleante mouse was the first of these mice to appear and is the best studied, in which the Herc1 mutation elicits: (i) delayed neural transmission in the peripheral nervous system; (ii) impaired learning, memory and motor control; and (iii) altered presynaptic membrane dynamics. In this review, we discuss the information currently available on HERC proteins in the nervous system and their biological activity, the dysregulation of which could explain certain neurodevelopmental syndromes and/or neurodegenerative diseases.

P-104 A STEP-UP APPROACH FROM IPOM + IN MINIMALLY INVASIVE ABDOMINAL WALL SURGERY

Aim

To compare the early outcomes of two different techniques for ventral hernia repair in our abdominal wall surgery unit.

Materials and Methods

A prospective non-randomized review was perfomed including patients who underwent laparoscopic hernia repair from January 2018 to April 2022. All patients were followed-up for 1 month and the hernia orifice was closed in all cases. Patients and hernias characteristics, operative data and early complications were reviewed. Postoperative pain was defined as ≥4 value in Visual Analogue Scale.

We compared 2 laparoscopic techniques: intraperitoneal mesh fixed with a double crown of resorbable tackers (IPOM+) and self gripping sublay positioned mesh (preperitoneal –PREP- or retromuscular –RIVES- position).

Outcomes

During the study period, 44 patients were assigned into 2 groups: 31 (70%) in IPOM+ group and 13 (30%) in Rives/Preperitoneal group. No differences were found in risk factors, population and hernia data between both groups. 6 patients (19%) from IPOM+ group presented postoperative pain and only 1 patient (7,7%) in Rives/Prep group (p: 0,30). There was no differences in other complications, length of stay or operative time.

Conlusion

Early outcomes of sublay techniques (Rives or preperitoneal) do not report more complications during perioperative time, but they could help reducing immediately postoperatorive pain.

The Other Side of SARS-CoV-2 Infection: Neurological Sequelae in Patients

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread around the globe causing coronavirus disease 2019 (COVID-19). Because it affects the respiratory system, common symptoms are cough and breathing difficulties with fever and fatigue. Also, some cases progress to acute respiratory distress syndrome (ARDS). The acute phase of COVID-19 has been also related to nervous system symptoms, including loss of taste and smell as well as encephalitis and cerebrovascular disorders. However, it remains unclear if neurological complications are due to the direct viral infection of the nervous system, or they appear as a consequence of the immune reaction against the virus in patients who presented pre-existing deficits or had a certain detrimental immune response. Importantly, the medium and long-term consequences of the infection by SARS-CoV-2 in the nervous system remain at present unknown. This review article aims to give an overview of the current neurological symptoms associated with COVID-19, as well as attempting to provide an insight beyond the acute affectation.

Selective deletion of Caspase-3 gene in the dopaminergic system exhibits autistic-like behaviour

Apoptotic caspases are thought to play critical roles in elimination of excessive and non-functional synapses and removal of extra cells during early developmental stages. Hence, an impairment of this process may thus constitute a basis for numerous neurological and psychiatric diseases. This view is especially relevant for dopamine due to its pleiotropic roles in motor control, motivation and reward processing. Here, we have analysed the effect of caspase-3 depletion on the development of catecholaminergic neurons and performed a wide array of neurochemical, ultrastructural and behavioural assays. To achieve this, we performed selective deletion of the Casp3 gene in tyrosine hydroxylase (TH)-expressing cells using Cre-loxP-mediated recombination. Histological evaluation of most relevant catecholaminergic nuclei revealed the ventral mesencephalon as the most affected region. Stereological analysis demonstrated an increase in the number of TH-positive neurons in both the substantia nigra and ventral tegmental area along with enlarged volume of the ventral midbrain. Analysis of main innervating tissues revealed a rather contrasting profile. In striatum, basal extracellular levels and potassium-evoked DA release were significantly reduced in mice lacking Casp3, a clear indication of dopaminergic hypofunction in dopaminergic innervating tissues. This view was sustained by analysis of TH-labelled dopaminergic terminals by confocal and electron microscopy. Remarkably, at a behavioural level, Casp3-deficient mice exhibited impaired social interaction, restrictive interests and repetitive stereotypies, which are considered the core symptoms of autism spectrum disorder (ASD). Our study revitalizes the potential involvement of dopaminergic transmission in ASD and provides an excellent model to get further insights in ASD pathogenesis.

HERC1 Ubiquitin Ligase Is Required for Hippocampal Learning and Memory

Mutations in the human HERC1 E3 ubiquitin ligase protein develop intellectual disability. The tambaleante (tbl) mouse carries a HERC1 mutation characterized by cerebellar ataxia due of adult cerebellar Purkinje cells death by extensive autophagy. Our previous studies demonstrated that both the neuromuscular junction and the peripheral nerve myelin sheaths are also affected in this mutant. Moreover, there are signs of dysregulated autophagy in the central nervous system in the tbl mouse, affecting spinal cord motor neurons, and pyramidal neurons of the neocortex and the hippocampal CA3 region. The tbl mutation affects associative learning, with absence of short- and long-term potentiation in the lateral amygdala, altered spinogenesis in their neurons, and a dramatic decrease in their glutamatergic input. To assess whether other brain areas engaged in learning processes might be affected by the tbl mutation, we have studied the tbl hippocampus using behavioral tests, ex vivo electrophysiological recordings, immunohistochemistry, the Golgi-Cox method and transmission electron microscopy. The tbl mice performed poorly in the novel-object recognition, T-maze and Morris water maze tests. In addition, there was a decrease in glutamatergic input while the GABAergic one remains unaltered in the hippocampal CA1 region of tbl mice, accompanied by changes in the dendritic spines, and signs of cellular damage. Moreover, the proportions of immature and mature neurons in the dentate gyrus of the tbl hippocampus differ relative to the control mice. Together, these observations demonstrate the important role of HERC1 in regulating synaptic activity during learning.

Reformulating Pro-Oxidant Microglia in Neurodegeneration

In neurodegenerative diseases, microglia-mediated neuroinflammation and oxidative stress are central events. Recent genome-wide transcriptomic analyses of microglial cells under different disease conditions have uncovered a new subpopulation named disease-associated microglia (DAM). These studies have challenged the classical view of the microglia polarization state’s proinflammatory M1 (classical activation) and immunosuppressive M2 (alternative activation). Molecular signatures of DAM and proinflammatory microglia (highly pro-oxidant) have shown clear differences, yet a partial overlapping gene profile is evident between both phenotypes. The switch activation of homeostatic microglia into reactive microglia relies on the selective activation of key surface receptors involved in the maintenance of brain homeostasis (a.k.a. pattern recognition receptors, PRRs). Two relevant PRRs are toll-like receptors (TLRs) and triggering receptors expressed on myeloid cells-2 (TREM2), whose selective activation is believed to generate either a proinflammatory or a DAM phenotype, respectively. However, the recent identification of endogenous disease-related ligands, which bind to and activate both TLRs and TREM2, anticipates the existence of rather complex microglia responses. Examples of potential endogenous dual ligands include amyloid β, galectin-3, and apolipoprotein E. These pleiotropic ligands induce a microglia polarization that is more complicated than initially expected, suggesting the possibility that different microglia subtypes may coexist. This review highlights the main microglia polarization states under disease conditions and their leading role orchestrating oxidative stress.

Abstract P3-08-18: Clinicopathological characteristics associated with intermediate and high-risk ODx RS

Background: The gene expression profiling assay OncotypeDx (ODx) prognosticates the risk of estrogen receptor positive (ER+) breast cancer (BC) recurrence and assesses the likely benefit from adjuvant chemotherapy in addition to endocrine therapy. There have been several attempts to develop algorithms that provide similar outcome prediction to the ODx assay with the use of routine clinicopathological characteristics. These models appear to predict high-risk ODx RS but are unable to reliably rule out the presence of patients with intermediate-risk disease. Our objective was to identify the clinicopathological factors associated with intermediate and high-risk categories.

Methods: We retrospectively reviewed the electronic medical records of patients with early-stage ER+ BC for whom ODx recurrence score (RS) was available. Patients were diagnosed and treated at 3 specialized cancer centers between 2010 and 2017. Two multinomial logistic regression models (crude and adjusted) were constructed to assess the association between clinicopathological characteristics and ODx RS as a categorical variable. The adjusted model included the following variables: ODx RS, age, tumor size, node status, grade, lymphovascular invasion and hormonal receptors. The reported association measure was the relative prevalence ratio (RPR) with its respective 95%CI.

Results: A total of 551 patients were included. Patients had a mean age of 56.2 ± 11.9 (SD) (range: 26-89). 9.6% (n=53) of patients were≤40 years old.The size of the tumors ranged from 0.1 cm to 7.2 cm (median = 1.5 cm; IQR 1.0-2.2cm). A minority of patients had lymph node involvement (5.8%, n=32). By subtype, carcinomas were mostly ductal (83.5%, n=460), followed by lobular (10.0%, n=55) and mucinous (3.5%, n=19). The majority of tumor exhibited an intermediate histological grade (71.6%, n=386). Ki 67 was available in 58.8% patients (n= 324), with a median Ki67 of 20 (IQR 10-30). In the adjusted multinomial logistic regression model, factors associated with ODx intermediate-risk category were grade 3 (RPR=4.78; 95%CI: 2.01-11.39) and having either ER or PR &lt;50 (RPR=2.80; 95%CI: 1.83-4.27). Factors associated with ODx high-risk category were grade 3 (RPR=15.89; 95%CI: 3.23-78.19), having either ER or PR &lt;50 (RPR=4.58; 95%CI: 2.37-8.87), age≤40 (RPR=2.96; 95%CI: 1.20-7.29) and T2-3 (RPR=2.20; 95%CI: 1.13-4.32).

Conclusion: Grade 3, ER o PR &lt;50, age ≤40 years and T2-3 are clinicopathological characteristics strongly associated with high-risk ODx RS. The associations with intermediate-risk ODx RS are weaker. The way these factors could be integrated into a clinicopathologic risk prediction model to identify high-risk patients needs further analysis.

Citation Format: Ruiz R, Morante Z, Namuche F, Urrunaga D, Leon M, Ziegler G, Aguilar A, Chavez Mac Gregor M, Gomez H. Clinicopathological characteristics associated with intermediate and high-risk ODx RS [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-08-18.

Abstract P3-08-16: Age's importance in early breast cancer: Oncotype Dx results in patients ≤40 years

Background

The 21-gene recurrence score (RS) predicts the benefit of adjuvant chemotherapy (CT) in ER-positive HER2-negative breast cancer (BC) and has been validated in population where women under 40 are underrepresented.Young BC pts are more likely to receive adjuvant chemotherapy (CT) in addition to endocrine therapy (ET). Our objective was to assess the RS results in young (≤40 yo) vs older (&gt;40 yo) pts and evaluate the impact of age on clinical decision-making according to RS categories.

Methods

We retrospectively reviewed electronic medical files of all patients with early stage hormone receptor BC for whom RS was available between 2007 and 2017 in 3 specialized cancer centers. We used the Mann-Whitney and Chi-squared tests to assess differences between age group. Similarly, we evaluated the association between age groups and treatment, within each ODx category. To determine if age was associated with CT use in the low risk category, a logistic regression model was constructed.

Results

A total of 551 pts were included, 53 (9.6%) ≤40 yo and 498 (90.4%) &gt;40 yo. No statistical differences were found between the younger and older groups in T (p=0.874), N (p=0.794), stage (p=0.188), or grade (p=0.791). Young patients underwent radical surgery more frequently than their older counterparts (41.5 vs 25.7%, p=0.014). Statistically significant differences were also observed in ER mean, which was lower in the younger group (80 vs 90%, p&lt;0.001). The median RS result was significantly higher in the younger group (19 vs 16, p=0.009). Also, high-risk recurrence score category was significantly more frequent in the younger group (22.6 vs 9.2%, p=0.009). In the intermediate-risk category there were no differences in the proportion of patients who received CT according to age groups (p=0.484). In the low-risk category, 28.0% of patients ≤40 years vs 11.3% of patients &gt;40 years received CT (p=0.037).

Conclusions

Our results indicate that RS tends to be higher in patients with BC ≤ 40 yo and that the frequency of high-risk RS is significantly higher in the younger group, suggesting biological differences between groups. 28% of young patients with low-risk RS from our cohort are overtreated. Based on these results, it should be considered to develop a test adjusted to the age of the patients.

Citation Format: Ruiz R, Namuche F, Morante Z, Aguilar A, Urrunaga D, Ziegler G, Chavez Mac Gregor M, Leon M, Gomez H. Age's importance in early breast cancer: Oncotype Dx results in patients ≤40 years [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-08-16.

Abstract P3-08-22: Oncotype Dx recurrence score risk groups according to Ki67, a predictor to be considered

Background

The gene expression profiling assay OncotypeDx (ODx) prognosticates the risk of estrogen receptor positive (ER+) breast cancer (BC) recurrence and assesses the likely benefit from adjuvant chemotherapy in addition to endocrine therapy. There have been several attempts to develop algorithms that provide similar outcome prediction to the ODx assay with the use of routine clinicopathological characteristics. Ki67 is frequently incorporated into these assessments, although there is no standard cut-off for its use.

Methods

We retrospectively reviewed the electronic medical records of 330 patients with early stage ER+ BC for whom ODx recurrence score (RS) was available. Patients were diagnosed and treated at two specialized cancer centers between 2014 and 2017.

Our objective was to determine the ki67's median differences between ODx risk groups.

We used Spearman rho for the correlation between Ki67 and ODx score and used Kruskal-Wallis test for compare medians, pairwaise comparison for the intergroup relations.

Results

Mean age at diagnosis was 57.42 years (range 28-89). Mean tumor diameter was 15.67 mm. 78.9% were intermediate histologic grade and 9.7% patients had lymph node involvement. Median expression of ER and PR were 90% (5-100) and 70% (0-100), respectively. We assessed the correlation between Ki67 and ODx score, with a pearson r:0.31, p&lt;0.001. The data showed a directly proportional trend between Ki67 and ODx score.

Median Ki67 was 20 (1-100). According to ODX RS, 61.5% of tumors were low risk, 30.3% were intermediate risk and, 8.2% were high risk. Median Ki67 within each category group is as follows: low: 15 (IQR:15), intermediate: 20 (IQR:18) and high: 40 (IQR:35), with a statistically significant difference between medians (p&lt;0.001). In the Pairwise comparison intergroup the data showed: Low-Intermediate (p&lt;0.05), Low-High (p&lt;0.001), Intermediate-High (p&lt;0.001).

Conclusions

The data showed directly proportional trend between Ki67 and ODx score. In our population there is a statistically significant difference between Ki67 medians according to ODx risk groups.

Citation Format: Namuche F, Ruiz R, Morante Z, Aguilar A, Gomez H. Oncotype Dx recurrence score risk groups according to Ki67, a predictor to be considered [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-08-22.

Abstract P3-08-17: Evaluation of Oncotype DX testing and subsequent treatment choices in the Latin American setting

Background: The gene expression profiling assay OncotypeDx (ODx) prognosticates the risk of estrogen receptor positive (ER+) breast cancer (BC) recurrence and assesses the likely benefit from adjuvant chemotherapy in addition to endocrine therapy. Numerous clinical utility studies have shown that acknowledging the RS impacts on clinical decision making, leading to a decrease in chemotherapy (CT) use. However, the cost of the assay limits it widespread use, especially in low and middle-income countries. Our objective was to determine the patterns of use of ODx, its results and the subsequent treatment choices in a large Latin American cohort.

Methods: We retrospectively reviewed the electronic medical records of patients with early-stage ER+ BC for whom ODx recurrence score (RS) was available. Patients were diagnosed and treated at 3 specialized Peruvian cancer centers between 2007 and 2017. Descriptive results for numeric variables were presented as means with standard deviation (SD) or medians with interquartile range (IQR), depending on their distributions; otherwise, we expressed the qualitative variables as numbers with percentages. We evaluated the association between ODx RS category and treatment using the Chi-squared test.

Results: A total of 551 patients were included. Patients had a mean age of 56.2 ± 11.9 (SD) (range: 26-89). 9.6% (n=53) of patients were ≤40 years old. The size of the tumors ranged from 0.1 cm to 7.2 cm (median = 1.5 cm; IQR 1.0-2.2cm). 36 (6.5%) patients had tumors ≤ 0.5cm and 7 (1%) had tumors &gt; 5cm. A minority of patients had lymph node involvement (5.8%, n=32). ODx was ordered in 55 cases (10%) of lobular carcinoma and in 23 cases (4%) of favorable histology tumors (19 mucinous, 4 tubular). Most tumors exhibited an intermediate histological grade (71.6%, n=386). Ki67 was available in 58.8% patients (n= 324), with a median Ki67 of 20 (IQR 10-30). Using commercial cutoffs RS was distributed as follows: low (0–17) = 316 (57.4%), intermediate (18–30) = 177 (32.1%), and high (≥31) = 58 (10.5%). In general, 57.5% (n=317) of patients received endocrine therapy (ET) as their only systemic treatment and 42.5% (n=234), also received CT (ET + CT). In the low-risk category, 87.3% (n=276) of patients received ET and 12.7% (n=40), ET + CT. Within the intermediate-risk category, most patients received ET + CT (77.4%, n=137). Only one patient in the high-risk category did not receive CT. There was a significant association between the RS group and treatment choice (p&lt;0.001).

Impact of ODx RS results on treatment recommendations Oncotype risk categories  LowIntermediateHighp valueTreatmentn%n%n%&lt;0.001Endocrine therapy27687.34022.611.7 Chemotherapy + Endocrine therapy4012.713777.45798.3 

Conclusion: ODx significantly influenced treatment decisions in our cohort, however an overutilization of CT was found in low-risk patients. Further data analysis is needed to explain the higher than expected use of CT. Also, there is room for improvement in the selection of cases that undergo ODx testing.

Citation Format: Ruiz R, Morante Z, Namuche F, Urrunaga D, Aguilar A, Schwarz J, Leon M, Ziegler G, Chavez Mac Gregor M, Gomez H. Evaluation of Oncotype DX testing and subsequent treatment choices in the Latin American setting [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-08-17.

HERC1 Ubiquitin Ligase Is Required for Normal Axonal Myelination in the Peripheral Nervous System

A missense mutation in HERC1 provokes loss of cerebellar Purkinje cells, tremor, and unstable gait in tambaleante (tbl) mice. Recently, we have shown that before cerebellar degeneration takes place, the tbl mouse suffers from a reduction in the number of vesicles available for release at the neuromuscular junction (NMJ). The aim of the present work was to study to which extent the alteration in HERC1 may affect other cells in the nervous system and how this may influence the motor dysfunction observed in these mice. The functional analysis showed a consistent delay in the propagation of the action potential in mutant mice in comparison with control littermates. Morphological analyses of glial cells in motor axons revealed signs of compact myelin damage as tomacula and local hypermyelination foci. Moreover, we observed an alteration in non-myelinated terminal Schwann cells at the level of the NMJ. Additionally, we found a significant increment of phosphorylated Akt-2 in the sciatic nerve. Based on these findings, we propose a molecular model that could explain how mutated HERC1 in tbl mice affects the myelination process in the peripheral nervous system. Finally, since the myelin abnormalities found in tbl mice are histological hallmarks of neuropathic periphery diseases, tbl mutant mice could be considered as a new mouse model for this type of diseases.

Abstract P1-06-12: Optimizing the use of oncotype Dx in early breast cancer

Background: Oncotype Dx (ODX) prognosticates the risk of recurrence and predicts the benefit of adjuvant chemotherapy in estrogen-receptor-positive breast cancer (BC). However, its cost makes it prohibitive for many health care systems. Our objective was to develop a model that uses routine clinical and pathological parameters to identify ODX high risk patients which require adjuvant chemotherapy.

Methods: We retrospectively reviewed ODX and pathology reports from 190 early BC patients treated between 2014 and 2016 in a specialized cancer center. Our population was divided into a training (n:133) and validation set (n:57). In the training set, among available clinico-pathological variables (age, T, ER, PR, Ki67, Elston-Ellis grade) a multiple linear regression model was carried out to select those significantly associated with ODX. Coefficients of statistically significant variables were used to build an equation. The equation was applied in the training set. These results were confronted to ODX categories. The best threshold for selecting high risk patients was identified in the training set and tested in the validation set.

Results: Among the tested variables, tumor size (pT), progesterone receptor (PR), Ki67 and Ellston-Ellis grade were significantly associated with ODX RS (Table 1). The linear predictor is: (0.2544 x pT) – (0.0739 x PR) + (0.0861 x Ki67) + (5.4232 x Elston grade). The threshold score for this equation was set on 14 to discriminate high from low-intermediate risk patients. The test was able to correctly classify high risk patients with a sensitivity of 78%, a specificity of 72% and a negative predictive value of 98%.

Conclusion: With further refinement ODX could be omitted in patients classified as high risk by our predictor therefore restricting and optimizing the use of ODX to a smaller population of patients. The observed ODX distribution in our patients is similar to previously reported series suggesting that this equation could be informative in similar clinical settings. Additional external testing using new datasets is ongoing.

Citation Format: Ruiz R, Namuche F, Flores C, Aguilar A, Gomez HL. Optimizing the use of oncotype Dx in early breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P1-06-12.

Abstract P6-09-11: Ki67 cut offs and oncotype DX recurrence score in early breast cancer

Background: The gene expression profiling assay OncotypeDx (ODX) predicts the likelihood of estrogen receptor (ER) positive breast cancer (BC) recurrence and assesses the likely benefit from both hormonal therapy and chemotherapy. Many clinical scores that estimate the risk category of ODX are being tested. Ki67 is frequently incorporated into these assessments, although there is no standard cut-off for its use.

Methods: We retrospectively reviewed the electronic medical records of 190 patients with early stage ER+ BC for whom ODX recurrence score (RS) was available. Patients were diagnosed and treated at a specialized cancer center between 2014 and 2016. Our objective was to find out the degree to which an optimal ki67 cut-off correlates with ODX risk category. We also aim to determine an association between classical clinicopathological variables (St. Gallen (SG) 2015) could predict ODX risk category. Chi square test was used.

Results: The characteristics of patients according to ODX risk category are shown in Table 2. Mean age at diagnosis was 59 years (range 28-89). Mean tumor diameter was 15mm, 84.2% were intermediate grade and 4.7% patients had lymph node involvement. Mean expression of ER, PR and Ki67 were 87%, 53% and 22%, respectively. According to ODX 62.1% patients were low risk, 30.5% were intermediate risk and 7.4% were high risk. An overall concordance of 46.8% (73/190) was found between SG 2015 and the risk category of ODX (75.7% for low, 33.3% for intermediate and 23.9% for high RS). When changing SG Ki67 cutoffs to ≤20% (for low Ki67) and ≥30% (for high Ki67), an overall concordance of 56.3% (107/190) was found (69.6% for low, 47.3% for intermediate and 23.9% for high RS) and this was statistically significant (p=0.00) (Table 3).

Conclusion: In our population there is no a direct correlation between classical clinicopathological variables and ODX score. Despite being a specialized center, the utility of classical clinicopathological variables for predicting ODX risk category is limited.

Citation Format: Namuche F, Ruiz R, Flores C, Gomez HL, Aguilar A. Ki67 cut offs and oncotype DX recurrence score in early breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P6-09-11.

Technique for precaval and laterocaval nodes excision at extraperitoneal paraaortic lymphadenectomy

STUDY OBJECTIVE

To describe our technique for excision of the pre-caval and laterocaval nodes using an extraperitoneal approach. This technique was developed to make the dissection and excision of the less accessible nodes in an easier and safer way by minimizing the risk of great vessels injury and bleeding.

DESIGN

Step-by-step description of the surgical procedure using video (Canadian Task Force classification III).

SETTING

The procedure was performed at a teaching hospital, Hospital Universitario Donostia (Spain).

PATIENTS

A 52-year-old woman with a body mass index of 33 underwent endoscopic extraperitoneal paraaortic lymphadenectomy for advanced high grade cervical adenocarcinoma FIGO IIB.

INTERVENTIONS

The patient underwent an endoscopic extraperitoneal para-aortic lymphadenectomy. An anatomical dissection is being performed being the upper limit of the dissection the left renal vein. Focus of the video involves the challenging dissection of the right nodes.

MEASUREMENTS AND MAIN RESULTS

Firstly we complete a dissection of all the anatomical aortic limits until the renal vein and exeresis of aortic nodes. A plane just above the cava vein is carefully developed by pushing all the lymph nodes to the roof of the dissection. Special care must be taken close to the aortic bifurcation due to the perforating vessels that can be found more frequently in this location. Once all this space is dissected, nodes attached to the roof are easily pushed down. It is useful to use a clip in the upper part, close to the renal vein, to prevent lymphorrhea. Nodes are excised in four blocks, supramesenteric and inframesenteric aortic and precaval nodes. The proximity to the peritoneal roof and the chance for a peritoneal hole and loss of pneumoperitoneum can be less problematic if the right dissection is performed at the end of the procedure.

CONCLUSION

A complete para-aortic retroperitoneal dissection can be achieved with this extraperitoneal approach. Benefits of this technique are based on the absence of the bowel or other intraperitoneal structures invading the operative field given the barrier-free nature of the retroperitoneal space. Despite the challenge of the access to the right nodes in a retroperitoneal paraaortic lymphadenectomy they can be successfully excised reaching the renal vein including obese patients.

[Triple arthrodesis for correction of cavovarus deformity]

OBJECTIVE

The aim is to correct the underlying cavovarus deformity and to achieve a pain-free and stable hindfoot.

INDICATIONS

Rigid neurologic, posttraumatic, congenital, and idiopathic cavovarus deformities.

CONTRAINDICATIONS

General surgical or anesthesiological risks, infections, critical soft tissue conditions, neurovascular impairment of the lower extremity, noncompliance, patients with severely reduced bone quality, insulin-dependent diabetes mellitus, smoking.

SURGICAL TECHNIQUE

The talonavicular and subtalar joints are exposed using a single medial approach. Joint cartilage is carefully debrided. Hindfoot reposition with complete correction of cavovarus deformity in all three planes. Joints are stabilized using cannulated screws, followed by wound closure.

POSTOPERATIVE MANAGEMENT

A soft wound dressing is used. Thromboprophylaxis is recommended. Patient mobilization starts on postoperative day 1 using a stabilizing walking boot or cast for 6 weeks with 15 kg partial weight bearing. Clinical and radiographic follow-up 6 weeks postoperatively to assess osseous consolidation at the arthrodesis site. Following clinical and radiographic follow-up at 6 weeks, full weight bearing is gradually initiated.

RESULTS

Between January 2012 and July 2014, triple arthrodesis was performed in 11 patients with a mean age of 62 ± 14 years due to cavovarus deformity. The mean follow-up was 34 ± 8 months (range 24-48 months). In all patients, the cavovarus deformity was substantially corrected. Significant pain relief from 7.1 ± 2.2 (range 5-10) to 1.8 ± 1.5 (range 0-4) on the visual analogue scale was observed.

AMPK Function in Aging Process

Aging involves the progressive deterioration of physiological functions, diminishing the individual's capacity for survival. Indeed, aging is the main risk factor for cancer, diabetes, cardiovascular disorders and neurodegenerative diseases. The discovery that the rate of aging is controlled by conserved genetic and biochemical pathways represented an unprecedented advance in aging research. The AMPK protein is a metabolic sensor that acts as a qualified cellular housekeeper, as well as controlling energy homeostasis and resistance to stress. Thus, the correct regulation of this factor enhances health and survival. In this manuscript we will review the molecular pathways regulated by AMPK that are related to the aging process, paying special attention to mitochondrial dysfunction, metabolic deregulation, cell senescence and autophagy.