Oncologic Outcome of Robotic-Assisted and Laparoscopic Sentinel Node Biopsy in Endometrial Cancer.

BACKGROUND: Recently, sentinel lymph node biopsy (SLNB) has been introduced in the surgical staging of endometrial cancer as an alternative to systematic lymph node dissection (LND). However, the survival impact of SLNB is not yet well characterised. METHODS: We performed a retrospective study of 419 patients with endometrial cancer treated with SLNB alone or with pelvic and para-aortic LND. For SLNB mapping, indocyanine green was used. RESULTS: Median follow-up was 66 months. After exclusions, 337 patients were eligible for analysis. Of them, 150 underwent SLNB and 187 LND. During the follow-up time, 27 (24.7%) of the 150 who underwent SLNB and 54 (28.9%) of the 187 who underwent LND were diagnosed with recurrent disease (p = 0.459). The estimated 5-year disease-free survival (DFS) rate was 76.7% and 72.2% for patients in the SLNB and LND group, respectively (p = 0.419). The 5-year overall survival (OS) rates were 80.7% and 77.0% in the SLNB and LND group, respectively (p = 0.895). Survival rates were similar in both groups independent of lymph node status. Multivariable analysis confirmed that the staging approach was not associated with oncological outcome. For patients without lymph node metastases, patient outcome was worsened by advanced tumour stage and non-endometrioid tumour histology. In the group of patients with confirmed lymph node metastases, advanced tumour stage and inadequate adjuvant treatment significantly reduced DFS and OS. CONCLUSION: Our data suggested that SLNB did not compromise the oncological outcome of patients with endometrial cancer compared to LND.

The representational geometry of emotional states in basolateral amygdala.

Sensory stimuli associated with aversive outcomes can cause multiple behavioral responses related to an animal's evolving emotional state. We employed chemogenetic inactivation and two-photon imaging to reveal how the basolateral amygdala (BLA) mediates these state changes. Mice were presented stimuli in a virtual burrow, causing two responses reflecting fear and flight to safety: tremble and ingress into the burrow. Inactivation eliminated differential tremble and ingress to aversive and neutral stimuli without eliminating responses themselves. Multiple variables, including stimulus valence and identity, and being in the tremble or ingressed state, typically modulated each neuron's activity (mixed-selectivity). BLA neural ensembles represented these variables even after neurons with apparent specialized selectivity were eliminated from analyses. Thus, implementing different readouts of BLA ensembles comprised of mixed-selectivity neurons can identify distinct emotional states defined by responses, like tremble for fear and ingress for safety. This mechanism relies on BLA's representational geometry, not its circuit specialization.

Methods for automating the analysis of live-cell single-molecule FRET data.

Single-molecule FRET (smFRET) is a powerful imaging platform capable of revealing dynamic changes in the conformation and proximity of biological molecules. The expansion of smFRET imaging into living cells creates both numerous new research opportunities and new challenges. Automating dataset curation processes is critical to providing consistent, repeatable analysis in an efficient manner, freeing experimentalists to advance the technical boundaries and throughput of what is possible in imaging living cells. Here, we devise an automated solution to the problem of multiple particles entering a region of interest, an otherwise labor-intensive and subjective process that had been performed manually in our previous work. The resolution of these two issues increases the quantity of FRET data and improves the accuracy with which FRET distributions are generated, increasing knowledge about the biological functions of the molecules under study. Our automated approach is straightforward, interpretable, and requires only localization and intensity values for donor and acceptor channel signals, which we compute through our previously published smCellFRET pipeline. The development of our automated approach is informed by the insights of expert experimentalists with extensive experience inspecting smFRET trajectories (displacement and intensity traces) from live cells. We test our automated approach against our recently published research on the metabotropic glutamate receptor 2 (mGluR2) and reveal substantial similarities, as well as potential shortcomings in the manual curation process that are addressable using the algorithms we developed here.

Protective effect of pre-operative conization in patients undergoing surgical treatment for early-stage cervical cancer.

OBJECTIVE: The aim of this study was to investigate the impact of pre-operative conization on disease-free survival (DFS) in early-stage cervical cancer. METHODS: In this population-based cohort study we analysed from clinical cancer registries to determine DFS of women with International Federation of Gynecology and Obstetrics (FIGO) stage IA1-IB1 cervical cancer with respect to conization preceding radical hysterectomy performed between January 2010 and December 2015. RESULTS: Out of 993 datasets available for the analysis, 235 patients met the inclusion criteria of the current study. The median follow-up was 5.4 years. During the study period, 28 (11.9%) recurrences were observed. All of these occurred in patients with FIGO stage IB1. For further evaluation, patients with FIGO IB1 tumors <2 cm were further analysed and divided into two groups, based on pre-operative conization. Pre-operative conization was associated with a reduced rate of recurrence (p = 0.007), with only three (5.2%) recurrences in this group (CO) compared to 25 recurrences (21.0%) in the group without conization (NCO) preceding radical hysterectomy. DFS was estimated at 79.0% and 94.8% in NCO and CO, respectively (p = 0.008). After adjustment for other prognostic covariates, conization remained a favourable prognostic factor for DFS (HR 0.27; 95% CI 0.08-0.93, p = 0.037). Lymph node involvement was the only unfavourable factor (HR 4.38; 95% CI 1.36-14.14, p = 0.014) in the multivariable analysis. CONCLUSIONS: Pre-operative conization is associated with improved DFS in early-stage cervical cancer independently of the surgical approach.

Contralateral lymph node metastases in patients with vulvar cancer and unilateral sentinel lymph node metastases.

INTRODUCTION: The risk of contralateral lymph node metastases following unilateral sentinel lymph node (SLN) metastases in patients with vulvar cancer(s) remains to be systematically assessed. MATERIAL AND METHODS: We performed a multicenter, retrospective registry-based study of 476 patients with vulvar cancer. The primary outcome measure was the rate of contralateral non-SLN metastases in the case of positive unilateral SLN. RESULTS: Out of 476 patients with primary vulvar cancer, 202 received SLN biopsy: 58 unilateral and 144 bilateral. Out of 66 patients with unilateral metastatic SLN, 62 (93.9%) received contralateral lymphadenectomy-18 after unilateral and 44 after bilateral SLN biopsy. In the study group, 132 SLN were assessed with a median number of 2 (range 1-4) per patient and 76 of these were positive. Lymph node-positivity was associated with advanced tumor stage, as well as lymph and vascular space invasion. In the group of patients with bilateral inguino-femoral lymphadenectomy, 1004 lymph nodes were resected with a median number of 15 (range 10-29) per patient. After full dissection of the inguino-femoral lymph nodes, no contralateral non-SLN metastases were found. CONCLUSIONS: The risk of contralateral non-SLN metastases in patients with unilateral SLN metastases was low. Therefore, the impact of contralateral lymphadenectomy on patient survival should be investigated in further studies.

Single-molecule FRET imaging of GPCR dimers in living cells.

Class C G protein-coupled receptors (GPCRs) are known to form stable homodimers or heterodimers critical for function, but the oligomeric status of class A and B receptors, which constitute >90% of all GPCRs, remains hotly debated. Single-molecule fluorescence resonance energy transfer (smFRET) is a powerful approach with the potential to reveal valuable insights into GPCR organization but has rarely been used in living cells to study protein systems. Here, we report generally applicable methods for using smFRET to detect and track transmembrane proteins diffusing within the plasma membrane of mammalian cells. We leverage this in-cell smFRET approach to show agonist-induced structural dynamics within individual metabotropic glutamate receptor dimers. We apply these methods to representative class A, B and C receptors, finding evidence for receptor monomers, density-dependent dimers and constitutive dimers, respectively.

Minimal-invasive or open approach for surgery of early cervical cancer: the treatment center matters.

PURPOSE: The aim of the study was to compare recurrence-free survival (RFS) and overall survival (OS) of patients with early stage cervical cancer in dependence of surgical approach and treatment center. PATIENTS AND METHODS: A population-based cohort study including women with early stage IA1-IIB2 cervical cancer treated by radical hysterectomy between January 2010 and December 2015 was performed. RESULTS: The median follow-up time was 5.6 years. After exclusions, 413 patients were eligible for analysis: 111 (26.9%) underwent minimal-invasive surgery (MIS) and 302 (73.1%) open surgery. Both treatment groups were well balanced regarding the clinical and pathological characteristics. The mean age of the patients was 51.0 years. MIS was associated with improved RFS and OS compared with the open surgery. The 5-year RFS rates were 89.2% in the MIS group and 73.4% in the open surgery group (p = 0.004). The 5-year OS rates were 93.7% in the MIS group and 81.8% in the open surgery group (p = 0.016). After adjustment for other prognostic covariates, the MIS was further associated with improved RFS (HR = 0.45, 95% CI 0.24-0.86; p = 0.015) but not with OS. Nevertheless, after adjustment for treatment center, the surgical approach was not associated with significant difference in RFS (HR = 0.61, 95% CI 0.31-1.19; p = 0.143). Overall survival of patients treated in university cancer centers was significantly increased compared to patients treated in non-university cancer centers. The treatment center remains a strong prognostic factor regarding RFS (HR = 0.49, 95% CI 0.28-0.83; p = 0.009) and OS (HR = 0.50, 95% CI 0.26-0.94; p = 0.031). CONCLUSIONS: The treatment center but not the surgical approach was associated with the survival of patients treated with radical hysterectomy for early stage cervical cancer.

Localized semi-nonnegative matrix factorization (LocaNMF) of widefield calcium imaging data.

Widefield calcium imaging enables recording of large-scale neural activity across the mouse dorsal cortex. In order to examine the relationship of these neural signals to the resulting behavior, it is critical to demix the recordings into meaningful spatial and temporal components that can be mapped onto well-defined brain regions. However, no current tools satisfactorily extract the activity of the different brain regions in individual mice in a data-driven manner, while taking into account mouse-specific and preparation-specific differences. Here, we introduce Localized semi-Nonnegative Matrix Factorization (LocaNMF), a method that efficiently decomposes widefield video data and allows us to directly compare activity across multiple mice by outputting mouse-specific localized functional regions that are significantly more interpretable than more traditional decomposition techniques. Moreover, it provides a natural subspace to directly compare correlation maps and neural dynamics across different behaviors, mice, and experimental conditions, and enables identification of task- and movement-related brain regions.

Detecting G protein-coupled receptor complexes in postmortem human brain with proximity ligation assay and a Bayesian classifier.

Despite the controversy regarding the existence and physiological relevance of class A G protein-coupled receptor dimerization, there is substantial evidence for functional interactions between the dopamine D2 receptor (D2R) and the adenosine A2A receptor (A2AR). A2AR-D2R complexes have been detected in rodent brains by proximity ligation assay; however, their existence in the human brain has not been demonstrated. In this study, we used Brightfield proximity ligation assay, combined with a systematic sampling and a parameter-free naive Bayesian classifier, and demonstrated proximity between the D2R and the A2AR in the adult human ventral striatum, consistent with their colocalization within complexes and the possible existence of D2R-A2AR heteromers. These methods are applicable to the relative quantification of proximity of two proteins, as well as the expression levels of individual proteins.

Evoked transients of pH-sensitive fluorescent false neurotransmitter reveal dopamine hot spots in the globus pallidus.

Dopamine neurotransmission is suspected to play important physiological roles in multiple sparsely innervated brain nuclei, but there has not been a means to measure synaptic dopamine release in such regions. The globus pallidus externa (GPe) is a major locus in the basal ganglia that displays a sparse innervation of en passant dopamine axonal fibers. Due to the low levels of innervation that preclude electrochemical analysis, it is unknown if these axons engage in neurotransmission. To address this, we introduce an optical approach using a pH-sensitive fluorescent false neurotransmitter, FFN102, that exhibits increased fluorescence upon exocytosis from the acidic synaptic vesicle to the neutral extracellular milieu. In marked contrast to the striatum, FFN102 transients in the mouse GPe were spatially heterogeneous and smaller than in striatum with the exception of sparse hot spots. GPe transients were also significantly enhanced by high frequency stimulation. Our results support hot spots of dopamine release from substantia nigra axons.

Accumbens dopamine D2 receptors increase motivation by decreasing inhibitory transmission to the ventral pallidum.

Dopamine D2 receptors (D2Rs) in the nucleus accumbens (NAc) regulate motivated behavior, but the underlying neurobiological mechanisms remain unresolved. Here, we show that selective upregulation of D2Rs in the indirect pathway of the adult NAc enhances the willingness to work for food. Mechanistic studies in brain slices reveal that D2R upregulation attenuates inhibitory transmission at two main output projections of the indirect pathway, the classical long-range projections to the ventral pallidum (VP), as well as local collaterals to direct pathway medium spiny neurons. In vivo physiology confirms the reduction in indirect pathway inhibitory transmission to the VP, and inhibition of indirect pathway terminals to VP is sufficient to enhance motivation. In contrast, D2R upregulation in the indirect pathway does not disinhibit neuronal activity of the direct pathway in vivo. These data suggest that D2Rs in ventral striatal projection neurons promote motivation by weakening the canonical output to the ventral pallidum.

Decreasing Striatopallidal Pathway Function Enhances Motivation by Energizing the Initiation of Goal-Directed Action.

UNLABELLED: Altered dopamine D2 receptor (D2R) binding in the striatum has been associated with abnormal motivation in neuropsychiatric disorders, including schizophrenia. Here, we tested whether motivational deficits observed in mice with upregulated D2Rs (D2R-OEdev mice) are reversed by decreasing function of the striatopallidal "no-go" pathway. To this end, we expressed the Gαi-coupled designer receptor hM4D in adult striatopallidal neurons and activated the receptor with clozapine-N-oxide (CNO). Using a head-mounted miniature microscope we confirmed with calcium imaging in awake mice that hM4D activation by CNO inhibits striatopallidal function measured as disinhibited downstream activity in the globus pallidus. Mice were then tested in three operant tasks that address motivated behavior, the progressive ratio task, the progressive hold-down task, and outcome devaluation. Decreasing striatopallidal function in the dorsomedial striatum or nucleus accumbens core enhanced motivation in D2R-OEdev mice and control littermates. This effect was due to increased response initiation but came at the cost of goal-directed efficiency. Moreover, response vigor and the sensitivity to changes in reward value were not altered. Chronic activation of hM4D by administering CNO for 2 weeks in drinking water did not affect motivation due to a tolerance effect. However, the acute effect of CNO on motivation was reinstated after discontinuing chronic treatment for 48 h. Used as a therapeutic approach, striatopallidal inhibition should consider the risk of impairing goal-directed efficiency and behavioral desensitization. SIGNIFICANCE STATEMENT: Motivation involves a directional component that allows subjects to efficiently select the behavior that will lead to an optimal outcome and an activational component that initiates and maintains the vigor and persistence of actions. Striatal output pathways modulate motivated behavior, but it remains unknown how these pathways regulate specific components of motivation. Here, we found that the indirect pathway controls response initiation without affecting response vigor or the sensitivity to changes in the reward outcome. A specific enhancement in the activational component of motivation, however, can come at the cost of goal-directed efficiency when a sustained response is required to obtain the goal. These data should inform treatment strategies for brain disorders with impaired motivation such as schizophrenia and Parkinson's disease.

Fluorescent false neurotransmitter reveals functionally silent dopamine vesicle clusters in the striatum.

Neurotransmission at dopaminergic synapses has been studied with techniques that provide high temporal resolution, but cannot resolve individual synapses. To elucidate the spatial dynamics and heterogeneity of individual dopamine boutons, we developed fluorescent false neurotransmitter 200 (FFN200), a vesicular monoamine transporter 2 (VMAT2) substrate that selectively traces monoamine exocytosis in both neuronal cell culture and brain tissue. By monitoring electrically evoked Ca(2+) transients with GCaMP3 and FFN200 release simultaneously, we found that only a small fraction of dopamine boutons that exhibited Ca(2+) influx engaged in exocytosis, a result confirmed with activity-dependent loading of the endocytic probe FM1-43. Thus, only a low fraction of striatal dopamine axonal sites with uptake-competent VMAT2 vesicles are capable of transmitter release. This is consistent with the presence of functionally 'silent' dopamine vesicle clusters and represents, to the best of our knowledge, the first report suggestive of presynaptically silent neuromodulatory synapses.

Evidence for limited D1 and D2 receptor coexpression and colocalization within the dorsal striatum of the neonatal mouse.

The striatum is the major input nucleus of the basal ganglia involved in reward processing, goal-directed behaviors, habit learning, and motor control. The striatum projects to the basal ganglia output nuclei via the "direct" and "indirect" pathways, which can be distinguished by their projection fields and their opposing effects on behavior. In adult animals, the functional opposition is modulated by the differential actions of D1 and D2 dopamine receptors (D1R, D2R), the expression of which is largely separated between these pathways. To determine whether a similar degree of separation exists earlier in development, we used dual-label immunohistochemistry to map dorsal-striatal D1R and D2R expression at the promoter level in postnatal day 0 (PD0) Drd1a-tdTomato/Drd2-GFP BAC transgenic mice, and at the receptor level by costaining for native D1R and D2R in wildtype (WT) PD0 animals. To assess for potential molecular interactions between D1R and D2R we also employed a recently developed proximity-ligation assay (PLA). Limited coexpression and colocalization of the D1R and D2R proteins was found in clusters of neurons endemic to the "patch" compartment as identified by costaining with tyrosine hydroxylase, but not outside these clusters. Moreover, in contrast to our recent findings where we failed to detect a D1R-D2R PLA signal in the adult striatum, in PD0 striatum we did identify a clear PLA signal for this pair of receptors. This colocalization at close proximity points to a possible role for D1R/D2R-mediated crosstalk in early striatal ontogeny.