TACR3 Research Articles

A novel role of NK3 receptor signaling in bipolar disorder

Objective: Bipolar disorder (BD) affects more than 1% of the global population with limited therapeutic options. The neurokinin B (NKB)-neurokinin B receptor (NK3R) is involved in a variety of emotional activities. This study explored the role of NK3 receptor signaling in bipolar disorder.Materials and methods: In this study, a model of intracerebroventricular (ICV) administration of OUA-induced BD was used to investigate the possible role of NK3R signaling in BD. The involvement of NK3R in the expression of OUA-induced BD was assessed by genetically knocking down the NK3R-encoding TACR3 gene with shRNA approach in the hippocampus and systemic administration of a NK3R antagonist ESN364,. Biochemical techniques were used to examine the NK3R-associated signaling changes and the oxidative stress parameters in the hippocampus of BD rats.Result: The NK3R expression level was elevated in the hippocampus BD rats. Both TACR3 knockdown in the hippocampus and ESN364 treatment reversed the manic-like and depression-like behaviors in BD rats Inhibition of the NK3R signaling reversed oxidative stress-induced damage via upregulating the BDNF signaling pathway in the hippocampus.Conclusion: These results demonstrated that NK3R signaling plays a key role in the pathogenesis of BD and that pharmacological antagonist of NK3R such as ESN364 could represent a novel therapeutic strategy for the management of BD.

Interplay between hippocampal TACR3 and systemic testosterone in regulating anxiety-associated synaptic plasticity

Tachykinin receptor 3 (TACR3) is a member of the tachykinin receptor family and falls within the rhodopsin subfamily. As a G protein-coupled receptor, it responds to neurokinin B (NKB), its high-affinity ligand. Dysfunctional TACR3 has been associated with pubertal failure and anxiety, yet the mechanisms underlying this remain unclear. Hence, we have investigated the relationship between TACR3 expression, anxiety, sex hormones, and synaptic plasticity in a rat model, which indicated that severe anxiety is linked to dampened TACR3 expression in the ventral hippocampus. TACR3 expression in female rats fluctuates during the estrous cycle, reflecting sensitivity to sex hormones. Indeed, in males, sexual development is associated with a substantial increase in hippocampal TACR3 expression, coinciding with elevated serum testosterone and a significant reduction in anxiety. TACR3 is predominantly expressed in the cell membrane, including the presynaptic compartment, and its modulation significantly influences synaptic activity. Inhibition of TACR3 activity provokes hyperactivation of CaMKII and enhanced AMPA receptor phosphorylation, associated with an increase in spine density. Using a multielectrode array, stronger cross-correlation of firing was evident among neurons following TACR3 inhibition, indicating enhanced connectivity. Deficient TACR3 activity in rats led to lower serum testosterone levels, as well as increased spine density and impaired long-term potentiation (LTP) in the dentate gyrus. Remarkably, aberrant expression of functional TACR3 in spines results in spine shrinkage and pruning, while expression of defective TACR3 increases spine density, size, and the magnitude of cross-correlation. The firing pattern in response to LTP induction was inadequate in neurons expressing defective TACR3, which could be rectified by treatment with testosterone. In conclusion, our study provides valuable insights into the intricate interplay between TACR3, sex hormones, anxiety, and synaptic plasticity. These findings highlight potential targets for therapeutic interventions to alleviate anxiety in individuals with TACR3 dysfunction and the implications of TACR3 in anxiety-related neural changes provide an avenue for future research in the field.

TAC3 regulates GnRH/gonadotropin synthesis in female chickens

Neurokinin B (NKB), a peptide encoded by the tachykinin 3 (TAC3), is critical for reproduction in all studied species. However, its potential roles in birds are less clear. Using the female chicken (c-) as a model, we showed that cTAC3 is composed of five exons with a full-length cDNA of 787 bp, which was predicted to generate the mature NKB peptide containing 10 amino acids. Using cell-based luciferase reporter assays, we demonstrated that cNKB could effectively and specifically activate tachykinin receptor 3 (TACR3) in HEK293 cells, suggesting its physiological function is likely achieved via activating cTACR3 signaling. Notably, cTAC3 and cTACR3 were predominantly and abundantly expressed in the hypothalamus of hens and meanwhile the mRNA expression of cTAC3 was continuously increased during development, suggesting that NKB-TACR3 may emerge as important components of the neuroendocrine reproductive axis. In support, intraperitoneal injection of cNKB could significantly promote hypothalamic cGnRH-Ι, and pituitary cFSHβ and cLHβ expression in female chickens. Surprisingly, cTAC3 and cTACR3 were also expressed in the pituitary gland, and cNKB treatment significantly increased cLHβ and cFSHβ expression in cultured primary pituitary cells, suggesting cNKB can also act directly at the pituitary level to stimulate gonadotropin synthesis. Collectively, our results reveal that cNKB functionally regulate GnRH/gonadotropin synthesis in female chickens.

Insights into the genetics of menopausal vasomotor symptoms: genome-wide analyses of routinely-collected primary care health records

BackgroundVasomotor symptoms (VMS) can often significantly impact women’s quality of life at menopause. In vivo studies have shown that increased neurokinin B (NKB) / neurokinin 3 receptor (NK3R) signalling contributes to VMS, with previous genetic studies implicating the TACR3 gene locus that encodes NK3R. Large-scale genomic analyses offer the possibility of biological insights but few such studies have collected data on VMS, while proxy phenotypes such as hormone replacement therapy (HRT) use are likely to be affected by changes in clinical practice. We investigated the genetic basis of VMS by analysing routinely-collected health records.MethodsWe performed a GWAS of VMS derived from linked primary-care records and cross-sectional self-reported HRT use in up to 153,152 women from UK Biobank, a population-based cohort. In a subset of this cohort (n = 39,356), we analysed exome-sequencing data to test the association with VMS of rare deleterious genetic variants. Finally, we used Mendelian randomisation analysis to investigate the reasons for HRT use over time.ResultsOur GWAS of health-records derived VMS identified a genetic signal near TACR3 associated with a lower risk of VMS (OR=0.76 (95% CI 0.72,0.80) per A allele, P=3.7x10-27), which was consistent with previous studies, validating this approach. Conditional analyses demonstrated independence of genetic signals for puberty timing and VMS at the TACR3 locus, including a rare variant predicted to reduce functional NK3R levels that was associated with later menarche (P = 5 × 10–9) but showed no association with VMS (P = 0.6). Younger menopause age was causally-associated with greater HRT use before 2002 but not after.ConclusionsWe provide support for TACR3 in the genetic basis of VMS but unexpectedly find that rare genomic variants predicted to lower NK3R levels did not modify VMS, despite the proven efficacy of NK3R antagonists. Using genomics we demonstrate changes in genetic associations with HRT use over time, arising from a change in clinical practice since the early 2000s, which is likely to reflect a switch from preventing post-menopausal complications in women with earlier menopause to primarily treating VMS. Our study demonstrates that integrating routinely-collected primary care health records and genomic data offers great potential for exploring the genetic basis of symptoms.

TAC3/TACR3 System Function in the Catadromous Migration Teleost, Anguilla japonica.

Neurokinin B (NKB), a member of the tachykinin (TAC) family, plays important roles in mammalian neuropeptide secretion in related to reproduction. However, its potential role in spawning migration teleost is less clear. In the present study, Japanese eel (Anguilla japonica) was employed to study the performance of NKB in regulating reproduction. Results showed that two tac3 and one tacr3 genes were identified in Japanese eel. Sequence analysis showed that two tac3 transcripts, tac3a and tac3b, encode four NKBs: NKBa-13, NKBa-10, NKBb-13, and NKBb-10. However, compared with other species, a mutation caused early termination of TACR3 protein was confirmed, leading to the loss of the 35 amino acid (aa) C-terminal of the receptor. Expression analysis in different tissues showed that both tac3a and tac3b mRNAs were highly expressed in the brain. In situ hybridization localized both tac3a and tac3b mRNAs to several brain regions, mainly in the telencephalon and hypothalamus. Because of the mutation in TACR3 of Japanese eel, we further analyzed whether it could activate the downstream signaling pathway. Luciferase assay results showed the negative regulation of cAMP Response Element (CRE) and Sterol Response Element (SRE) signal pathways by Japanese eel NKBs. Intraperitoneal injection of four different NKB mature peptides at 100 ng/g had negative effect on either gnrh or gth gene expression. However, the high concentration of NKBa-10 and NKBb-13 (1,000 ng/g) upregulated mgnrh and fshb or lhb expression level significantly, which may be mediated by other receptors. In general, the NKBs/NK3Rs system has important functions in regulating eel puberty onset.

Shared genetic influences on depression and menopause symptoms.

Women experience major depression and post-traumatic stress disorder (PTSD) approximately twice as often as men. Estrogen is thought to contribute to sex differences in these disorders, and reduced estrogen is also known to be a key driver of menopause symptoms such as hot flashes. Moreover, estrogen is used to treat menopause symptoms. In order to test for potential shared genetic influences between menopause symptoms and psychiatric disorders, we conducted a genome-wide association study (GWAS) of estrogen medication use (as a proxy for menopause symptoms) in the UK Biobank. The analysis included 232 993 women aged 39-71 in the UK Biobank. The outcome variable for genetic analyses was estrogen medication use, excluding women using hormonal contraceptives. Trans-ancestry GWAS meta-analyses were conducted along with genetic correlation analyses on the European ancestry GWAS results. Hormone usage was also tested for association with depression and PTSD. GWAS of estrogen medication use (compared to non-use) identified a locus in the TACR3 gene, which was previously linked to hot flashes in menopause [top rs77322567, odds ratio (OR) = 0.78, p = 7.7 × 10-15]. Genetic correlation analyses revealed shared genetic influences on menopause symptoms and depression (rg = 0.231, s.e.= 0.055, p = 2.8 × 10-5). Non-genetic analyses revealed higher psychiatric symptoms scores among women using estrogen medications. These results suggest that menopause symptoms have a complex genetic etiology which is partially shared with genetic influences on depression. Moreover, the TACR3 gene identified here has direct clinical relevance; antagonists for the neurokinin 3 receptor (coded for by TACR3) are effective treatments for hot flashes.

Genetic factors in precocious puberty

Pubertal onset is known to result from reactivation of the hypothalamic-pituitary-gonadal (HPG) axis, which is controlled by complex interactions of genetic and nongenetic factors. Most cases of precocious puberty (PP) are diagnosed as central PP (CPP), defined as premature activation of the HPG axis. The cause of CPP in most girls is not identifiable and, thus, referred to as idiopathic CPP (ICPP), whereas boys are more likely to have an organic lesion in the brain. ICPP has a genetic background, as supported by studies showing that maternal age at menarche is associated with pubertal timing in their offspring. A gain of expression in the kisspeptin gene (KISS1), gain-of-function mutation in the kisspeptin receptor gene (KISS1R), loss-of-function mutation in makorin ring finger protein 3 (MKRN3), and loss-of-function mutations in the delta-like homolog 1 gene (DLK1) have been associated with ICPP. Other genes, such as gamma-aminobutyric acid receptor subunit alpha-1 (GABRA1), lin-28 homolog B (LIN28B), neuropeptide Y (NPYR), tachykinin 3 (TAC3), and tachykinin receptor 3 (TACR3), have been implicated in the progression of ICPP, although their relationships require elucidation. Environmental and socioeconomic factors may also be correlated with ICPP. In the progression of CPP, epigenetic factors such as DNA methylation, histone posttranslational modifications, and noncoding ribonucleic acids may mediate the relationship between genetic and environmental factors. CPP is correlated with short- and long-term adverse health outcomes, which forms the rationale for research focusing on understanding its genetic and nongenetic factors.

Insights from RNA-Seq analysis of Alzheimer's data suggest upregulation of GPCRs

Alzheimer's disease (AD) a complex neurodegenerative disorder and the most common cause of dementia in older people. Recently computational approaches have been integrated with genomics to discover novel genes involved in pathogenesis as well as to understand their mechanism. In this study we analyzed RNA-Seq data from different brain regions of AD patients and compared them with healthy individuals. Quantitative analysis of AD and control samples helped to find out differentially expressed genes (DEGs). Gene enrichment and pathway analysis were also performed to explore additional knowledge about DEGs. Study about protein-protein interaction/gene interaction, hub genes and modules helped in identifying crucial genes. It was revealed that ACKR3, CXCR4, DACH1, CDC6, GMNC, PELI2, DPP4, HSPA1L and PCGF genes were downregulated while CHRM5, CYSTLTR2, DRD5, HTR2C, PTGFR, TACR3, TRHR, MAS1, CARTPTs, DDX3Y, KDMD5, SST, GALR1, NOV, SERPINE1, HLA-B, TRIM26, and BAG-6 genes were found to be upregulated in case of AD. Network analysis of DEGs helped in understanding key pathways involved in AD disease. The analytics revealed a connection between upregulated GPCRs, presence of Aβ granules and formation of Neurofibrillary tangles. It also provides a basis of identification of novel markers and therapeutic targets for Alzheimer's disease.

Tacr3/NK3R: Beyond Their Roles in Reproduction.

The Tacr3 gene encodes tachykinin receptor 3 (NK3R), which belongs to the tachykinin receptor family. This family of proteins includes typical G protein-coupled receptors and belongs to the rhodopsin subfamily. NK3R functions by binding to its high-affinity ligand, neurokinin B(NKB). The role of Tacr3/NK3R in growth and reproduction has been extensively studied, but Tacr3/NK3R is also widely expressed in the nervous system from the spinal cord to the brain and is involved in both physiological and pathological processes in the nervous system, including mood disorders, chronic pain, learning and memory deficiencies, Alzheimer's disease, Parkinson's disease, addiction-related processes, hypoxic-ischemic encephalopathy, body fluid management, neural development, and schizophrenia. Here, we summarize the structure of NK3R/NKB and its cellular signaling as well as the expression of Tacr3/NK3R in the nervous system, and we provide a comprehensive summary of the role of Tacr3/NK3R in neurological diseases, including reproduction-related disorders and other neurological diseases. At the end of this review, we propose the hypothesis that Tacr3/NK3R mediates a variety of brain functions by affecting the excitability of different neurons with specific functions. On the basis of this "excited or not" hypothesis, more studies related to Tacr3 should be carried out in other nervous system diseases in order to better understand the biological roles of Tacr3.

TAC3 Gene Products Regulate Brain and Digestive System Gene Expression in the Spotted Sea Bass (Lateolabrax maculatus).

Neurokinin B (NKB) is a member of the tachykinin (tac) family that plays important roles in mammalian growth by modulating prolactin (PRL) synthesis and secretion and causing contraction of the stomach and intestine. However, its potential role in regulating growth of teleosts is less clear. We aimed to explore the role that NKB plays in regulating fish growth using the spotted sea bass (Lateolabrax maculatus) as a model. In the present study, two tac3 and two tacr3 genes were identified in the spotted sea bass. Sequence analysis showed that two tac3 transcripts, tac3a and tac3b, encode four NKBs: NKBa-13, NKBa-10, NKBb-13, and NKBb-10. Expression analysis in different tissues showed that both genes are highly expressed in the brain, stomach and intestine of the spotted sea bass. In situ hybridization indicated that the tac3a and tac3b mRNAs are both localized in several brain regions, such as the telencephalon and hypothalamus, and that tacr3a and tacr3b are localized in the intestinal villus and gastric gland. To investigate the potential role of NKBs in regulating growth, in vitro experiments were performed to detect the effect of NKBs on growth-related gene expression in the brain and brain-gut peptide (BGP)-related genes in the stomach and intestine. NKBb-13 was the most critical ligand in regulating the expression of growth-related genes in the brain and brain-gut peptide (BGP)-related genes in the stomach. The expression of cholecystokinin (cck) was enhanced by NKBa-13, NKBa-10, and NKBb-10 but not NKBb-13 in the intestine. In general, our results showed that NKBs participate in regulating the growth of spotted sea bass.

IGFs Potentiate TAC3-induced SLα Expression via Upregulation of TACR3 Expression in Grass Carp Pituitary Cells.

In mammals, the tachykinin 3 (TAC3)/tachykinin receptor 3 (TACR3) systems have been confirmed to play an important role in the regulation of puberty onset. Using grass carp pituitary cells as the model, our recent study found that the TAC3 gene products could significantly induce somatolactin α (SLα) synthesis and secretion via TACR3 activation. In the present study, we seek to examine if pituitary TACR3 can serve as a regulatory target and contribute to TAC3 interactions with other SLα regulators. Firstly, grass carp TACR3 was cloned and tissue distribution showed that it could be highly detected in grass carp pituitary. Using HEK293 cells as the model, functional expression also revealed that grass carp TACR3 exhibited ligand binding selectivity and post-receptor signaling highly comparable to its mammalian counterpart. Using grass carp pituitary cells as the model, TACR3 mRNA expression could be stimulated by insulin-like growth factor (IGF)-I and -II via the IGF-I receptor coupled to phosphatidylinositol-3-kinase (PI3K)/protein kinase B (Akt) and mitogen-activated protein kinase (MAPK) pathways. Interestingly, IGF-I/-II cotreatment could also significantly enhance TAC3-induced SLα mRNA expression and the potentiating effect was dependent on TACR3 expression and activation of adenylate cyclase (AC)/cAMP/protein kinase A (PKA), phospholipase C (PLC)/inositol 1,4,5-triphosphate (IP3)/protein kinase C (PKC), and Ca2+/calmodulin (CaM)/calmodulin-dependent protein kinase II (CaMK-II) cascades. Besides, IGF-I-induced Akt phosphorylation but not MEK, extracellular signal-regulated kinase (ERK1/2), and P38MAPK phosphorylation was notably enhanced by TACR3 activation. These results, as a whole, suggest that the potentiating effect of IGFs on TAC3 gene products-induced SLα mRNA expression was mediated by TACR3 upregulation and functional crosstalk of post-receptor signaling in the pituitary.

A novel stopgain mutation c.G992A (p.W331X) in TACR3 gene was identified in nonobstructive azoospermia by targeted next-generation sequencing.

Nonobstructive azoospermia (NOA) is one of the most severe forms of male infertility because of impaired spermatogenesis with the absence of spermatozoa in the ejaculate. The causes of this disease can be partly attributed to genetic factors. Some common structural variants and single nucleotide polymorphisms (SNPs) were reported to be associated with NOA. However, the underlying etiology and genetic mechanism(s) remain largely unclear. The aim of this study was to investigate the associated mutations of spermatogenic genes in Chinese infertile men with NOA. The entire coding region of 25 genes associated with spermatogenesis was sequenced from 200 infertile men with NOA. Screening was carried out using the targeted exome sequencing to identify genetic variations and SNPs of the entire coding region of these genes. After the targeted exome sequencing data were filtered through several currently existing variation databases, a series of variations were found. In this paper, we report one novel stopgain variation c.G992A (p.W331X) in the exon 4 of TACR3 gene. The variant was heterozygous and categorized as pathogenic. In conclusion, our study revealed a novel stopgain mutation c.G992A (p.W331X) in TACR3 which expanded the mutation spectrum of TACR3 in Chinese NOA infertile men and advanced our understanding of the genetic susceptibility to NOA.

Characterisation, localisation and expression of porcine TACR1, TACR2 and TACR3 genes

Substance P is involved in many physiological and pathophysiological processes. This functional diversity is mediated by three neurokinin receptor subtypes (NK1R, NK2R and NK3R) encoded by the TACR1, TACR2 and TACR3 genes, respectively. Despite the increasing interest in using pigs (Sus scrofa) to study human disease mechanisms, the sequences of these receptors are still unconfirmed or in the case of the NK1 receptor, not yet even unpredicted. We employed in silico analysis to define the localisation of the porcine tachykinin receptor genes, and to predict the structures and amino acid sequences of the respective proteins. A reverse transcription polymerase chain reaction (RT-PCR) assay was performed to analyse the expression of tachykinin receptor genes in different porcine tissues. The data show that the TACR1 gene is located on chromosome 3, TACR2 on chromosome 14 and TACR3 on chromosome 8. All three genes encode proteins with structures that incorporate features of G-protein-coupled receptors with sizes of 407, 381 and 464 amino acids, respectively. The receptors display a high degree of similarity to other mammalian neurokinin receptors. The NK1R subtype is expressed in both the central nervous system and peripheral tissues, while NK2R expression seems to be localised mostly to peripheral tissues. The expression of NK3R is found mainly in the central nervous system. This report provides for the first time the results of a comprehensive analysis of the structure and distribution of porcine NK1R, as well as other porcine neurokinin receptors and their genes. We hope that our data may offer an invaluable foundation for the future studies on the function of diverse tachykinin peptides in the central nervous system and peripheral tissues.

Association of genetic variation in the tachykinin receptor 3 locus with hot flashes and night sweats in the Women's Health Initiative Study.

Vasomotor symptoms (VMS, ie, hot flashes or night sweats) are reported by many, but not all, women. The extent to which VMS are genetically determined is unknown. We evaluated the relationship of genetic variation and VMS. In this observational study, we accessed data from three genome-wide association studies (GWAS) (SNP Health Association Resource cohort [SHARe], WHI Memory Study cohort [WHIMS+], and Genome-Wide Association Studies of Treatment Response in Randomized Clinical Trials [GARNET] studies, total n = 17,695) of European American, African American, and Hispanic American postmenopausal women aged 50 to 79 years at baseline in the Women's Health Initiative Study. We examined genetic variation in relation to VMS (yes/no) in each study and using trans-ethnic inverse variance fixed-effects meta-analysis. A total of 11,078,977 single-nucleotide polymorphisms (SNPs) met the quality criteria. After adjustment for covariates and population structure, three SNPs (on chromosomes 3 and 11) were associated with VMS at the genome-wide threshold of 5 × 10 in the African American SHARe GWAS, but were not associated in the other cohorts. In the meta-analysis, 14 SNPs, all located on chromosome 4 in the tachykinin receptor 3 (TACR3) locus, however, had P < 5 × 10. These SNPs' effect sizes were similar across studies/participants' ancestry (odds ratio ∼1.5). Genetic variation in TACR3 may contribute to the risk of VMS. To our knowledge, this is the first GWAS to examine SNPs associated with VMS. These results support the biological hypothesis of a role for TACR3 in VMS, which was previously hypothesized from animal and human studies. Further study of these variants may lead to new insights into the biological pathways involved in VMS, which are poorly understood.

Genome-Wide Association Study of the Human Genetic Factors Influencing the Risk of Adverse Events during Idelalislib Therapy in Patients with Relapsed Indolent Lymphoma

Introduction: Idelalisib (IDELA) is a selective inhibitor of PI3Kδ that has demonstrated efficacy in indolent lymphoma. In the NCT01659021 (101-09) study in patients (pts) with previously treated iNHL, the ORR was 57%. However, in this heavily-treated and refractory population, 27.2% (34/125 pts) discontinued the study due to reported ≥ grade 3 adverse events (AEs). This analysis aims to investigate an underlying genetic molecular mechanism(s) that may contribute to IDELA associated AEs.Methods: We performed a genome-wide association study (GWAS) to determine if common genetic factors influence the risk of AEs. We utilized available DNA samples from 66 subjects from the 101-09 clinical study to conduct genotyping at 2,088,393 single nucleotide polymorphisms (SNPs) using the Illumina HumanOmni2.5 high-density BeadArray chip. In parallel, we also conducted Illumina whole exome sequencing (WES) to identify causal functional variation, as well as to examine the role of rare functional variations that may influence the development of AEs. The phenotypic endpoints assessed in this GWAS analysis were: grade ≥3 any AE, diarrhea/colitis (DC), abnormal liver function test (LFT) and pneumonitis. True controls were defined as subjects with no reported AEs of any grade.Results: Logistic regression analysis of the combined AE groups, DC, and pneumonitis status, identified no common SNPs among Caucasians, or any ethnic subgroups that exceeded the genome-wide threshold for statistical significance. For the abnormal LFT phenotype, a total of seven SNPs (four in the all ethnicity and three in the Caucasian subgroup analysis) were found to exceed the genome-wide threshold for statistical significance. Six of these SNPs were considered false positives resulting from the small sample size. The remaining SNP (rs1351623), located in intron 1 of the tachykinin receptor 3 (TACR3) gene, was present in 12 out of 23 controls (minor allele frequency of 28.3% vs. 17.6% in the general population), but was completely absent from the 9 pts in the abnormal LFT case group, suggesting that the minor allele may be protective against altered liver function. However, TACR3 does not have an obvious biological role in mediating liver function and we were unable to identify any potentially causal functional variants in TACR3 or any other genes in close proximity which could sufficiently explain the observed association. Follow-up analysis of this association using statistical tests more robust for rare data indicated that this association may much more likely be due to chance (p=0.0187; Firth logistic regression). Analyses of the WES dataset using single variant and gene-based collapsing tests showed no single nucleotide variants or genes that exceeded the threshold for statistical significance after correcting for multiple testing.Conclusion: With the current dataset, no evidence was observed to support a role for human genetic variation of large effect size in influencing the risk of AEs during IDELA therapy. In pts with abnormal LFTs, we identified 7 SNPs that exceeded the genome-wide threshold for statistical significance. All but one of these associations were found to be false positives and there was no compelling evidence to support the remaining association with the rs1351623 SNP in TACR3. In both the GWAS and WES, significance scores from virtually all association analyses showed evidence of moderate p-value deflation, suggesting that the analyses were underpowered due to the limited sample size of the study. Therefore, further genetic studies using larger cohorts of patients treated with IDELA are needed to determine if genetic factors influence the risk of adverse events. DisclosuresGoldstein:Astra Zeneca: Consultancy; Janssen: Consultancy; Pairnomix: Consultancy, Equity Ownership, Membership on an entity's Board of Directors or advisory committees; Clarus: Consultancy, Equity Ownership, Membership on an entity's Board of Directors or advisory committees; LabCorp: Consultancy, Equity Ownership, Membership on an entity's Board of Directors or advisory committees; Lilly: Consultancy. Munugalavadla:Gilead Sciences: Employment, Equity Ownership. Dreiling:Gilead Sciences: Employment, Equity Ownership. Jurczak:Acerta: Research Funding; Janssen: Research Funding; Bayer: Research Funding; Gilead Sciences: Research Funding; Celltrion, Inc: Research Funding. Flinn:Janssen: Research Funding; Pharmacyclics LLC, an AbbVie Company: Research Funding; Gilead Sciences: Research Funding; ARIAD: Research Funding; RainTree Oncology Services: Equity Ownership. Salles:Mundipharma: Honoraria; Amgen: Consultancy, Honoraria; Novartis: Consultancy, Honoraria; Celgene: Consultancy, Honoraria; Gilead: Honoraria, Research Funding; Janssen: Consultancy, Honoraria; Roche/Genentech: Consultancy, Honoraria, Research Funding.

Tachykinin Receptor 3 Distribution in Human Oral Squamous Cell Carcinoma.

Tachykinin 3 (TAC3) and its preferred tachykinin receptor 3 (TACR3) that are prominently detected in the central nervous system, play significant roles in physiological development and specifically in the human reproductive system. The roles of TAC3/TACR3 in oral squamous cell carcinoma are unknown. We examined the expression pattern of TAC3/TACR3 in clinically-resected oral squamous cell carcinoma samples using immunohistochemistry and immunofluorescence analysis. We found that even though the expression level of TACR3 was negative in the normal epithelium, it was highly elevated in tumor cells. A more intense signal was observed in the invasive front of tumor cells that had migrated into the mandible bone matrix. TAC3 was not detected in tumor cells, but was expressed in PGP-9.5-positive sensory nerves in the mandible. Our results suggest that peripheral sensory nerve-derived TAC3 may affect gingival oral squamous cell carcinoma cells through TACR3 in the bone matrix.

Prevalence of KISS1 Receptor mutations in a series of 603 patients with normosmic congenital hypogonadotrophic hypogonadism and characterization of novel mutations: a single-centre study.

What is the exact prevalence of Kisspeptin Receptor (KISS1R) mutations in the population of patients with normosmic congenital hypogonadotrophic hypogonadism (nCHH) by comparison with other genes, involved in gonadotrophin-releasing hormone (GnRH) release or action? KISS1R mutants are responsible for the nCHH phenotype in only a small minority of cases and were less prevalent than GnRH Receptor (GNRHR) mutations. The respective prevalence of each of the genetic causes of nCHH is unclear. Large series of patients are very rare and suffer from heterogeneity of the population of CHH studied. Patients with nCHH were consecutively enrolled in a single French referral centre and were gradually tested for KISS1R between January 2006 and April 2015. A total of 603 patients with nCHH (399 men and 204 women) were diagnosed at the Bicêtre Hospital and underwent KISS1R analysis. The GNRHR, tachykinin receptor 3 (TACR3), gonadotrophin-releasing hormone 1 (GNRH1), tachykinin 3 (TAC3) and KISS1 genes were also sequenced. Functional characterization of KISS1R mutations included a study of signal transduction using a reporter gene (serum response element-luciferase (SRE-Luc) involved in the mitogen-activated protein (MAP) kinase pathway. We detected 15 KISS1R variants (10 novel), in 12 of the 603 patients (2.0%, 95% CI [0.9-3.1]. KISS1R mutations were less prevalent than GNRHR (4.7%) and TACR3 (2.6%) mutations but more prevalent than GNRH1 (1.5%), TAC3 (1.0%) and KISS1 (0%) mutations. KISS1R mutants were present in the biallelic state in 8 of the 12 patients concerned. Among 5 men with biallelic KISS1R mutations, 4 had either micropenis or cryptorchidism. In vitro analysis of the 5 new variants present in the biallelic state (C95W, Y103*, C115W, P176R and A287E) showed a loss of function. The prevalence of TACR3, GNRH1, TAC3 and KISS1 mutations was calculated from a smaller number of nCHH patients than KISS1R and GNRHR. This should prompt caution concerning the reported prevalence of mutations in these four genes. We show that KISS1R mutants are responsible for the nCHH phenotype in only a small minority of cases. Together, the genes analysed here were mutated in fewer than 15% of patients, suggesting a role of other genes in nCHH. The presence of cryptorchidism and/or micropenis in the majority of men with biallelic KISS1R mutations strongly suggests that this gene is essential for prenatal GnRH secretion. This work was supported in part by grants from Paris-Sud University (Bonus Qualité Recherche, and Attractivité grants) to J.B., French Ministry of Health, Hospital Clinical Research Program on Rare Diseases. Assistance Publique Hôpitaux de Paris, Programme Hospitalier de Recherche Clinique (PHRC # P081212 HYPOPROTEO) to J.Y. C.P. was supported by student fellowships 'Année Recherche' from Agence Régionale de Santé Provence Alpes Côtes d'Azur. The authors have nothing to disclose.

Assessment of Tachykinin Receptor 3' Gene Polymorphism rs3733631 in Rosacea.

Background. Rosacea is a chronic skin disease, possibly following the neurogenic skin inflammation model. Neurokinin B, involved in the pathogenesis of Parkinson's disease, frequently coexisting with subsequent onset of rosacea, is an endogenous ligand of the tachykinin receptor 3 (TACR3). Methods. 128 rosacea patients and 121 matched controls were genotyped for rs3733631 by PCR-RFLP and analyzed by chi-square test. Results. We observed statistically significant predominance of the C/G or G/G genotype (p = 0.006) and of the G allele (p = 0.004) in the papulopustular (PP) form of rosacea and statistically marginal significance of the C/G or G/G genotype in erythematotelangiectatic (ET) rosacea (p = 0.052). Significantly higher frequency of the C/G or G/G genotype and G allele in PP rosacea (p = 0.021 and p = 0.008, resp.) was ascertained within male patients. Conclusion. TACR3 rs3733631 G allele possibly predisposes the evolution of the initial phase of rosacea to the PP and not the ET form in male patients.

TACkling NKB's role in puberty.

Over the past decade, scientists have unveiled the central importance of kisspeptin (Kiss1) signaling in the brain for control of GnRH secretion (1). However, neurokinin B (NKB), a member of the tachykinin peptide family, enjoys prominence as a Kiss1 cotransmitter and harbors secrets untold. NKB, along with Kiss1 and dynorphin, is synthesized and released by so-called “KNDy” neurons located within the arcuate nucleus of the hypothalamus (a homologue of the infundibular nucleus in primates) (2–5). NKB is encoded by the TAC3 gene in humans and the Tac2 gene in mice; the NKB receptor (NK3R) is encoded by the TACR3 gene in humans and the Tacr3 gene in mice. Kiss1 reigns as the most potent secretagogue for GnRH and LH secretion, and KNDy neurons serve as the nodal point for sex steroiddependent feedback control of GnRH and LH secretion in both sexes (6, 7). Dynorphin suppresses GnRH release by inhibiting KNDy neuronal activity and may be responsible for interrupting GnRH secretion during the interpulse intervals of Kiss1/GnRH secretion (8, 9). In contrast, NKB stimulates KNDy neuronal activity and thereby indirectly triggers GnRH (and LH) secretion (8, 10–12). Kiss1 and NKB play key roles in modulating GnRH secretion and, thus, reproductive function in both male and female animals (13– 16). Indeed, humans with impaired TAC3 and TACR3 signaling (as a result of mutations) exhibit hypogonadotropic hypogonadism, reminiscent of patients with KISS1R mutations (17–20). However, the observation of a “reversal” phenomenon in which TAC3/TAC3R-impaired hypogonadotropic hypogonadism patients regain hypothalamicpituitary-gonadal function after treatment disputes the notion that NKB signaling is a prerequisite for sustaining normal reproduction (21–23). Studies of NKB signaling in mice have generated intriguing, albeit paradoxical, findings. In 2012, Seminara and coworkers (24) demonstrated that mice lacking the gene encoding NK3R (Tacr3-null) exhibit significant reproductive impairment, despite being technically “fertile” as adults. In an editorial commentary on this article, we noted incongruities between the effects of genetically targeted NKB receptor ablations in mice and TACR3 mutations in humans, and we posed several questions. Why do humans bearing a TACR3 mutation exhibit infertility (notwithstanding phenotypic reversal after treatment), whereas Tacr3-null mice enter puberty normally and exhibit normal fertility? Why do humans with TACR3 mutations exhibit delayed puberty, but mice lacking Tacr3 exhibit no reproductive impairment until adulthood? To address these and other questions, the Seminara team broadened its approach and began searching for a better model of disrupted NKB signaling. In the current issue of Endocrinology, True et al (25) present a detailed analysis of the reproductive phenotypes of male and female mice that are homozygous for mutations in Tac2. On the one hand, male Tac2 / mice progress normally through puberty and become fertile in adulthood. To the contrary, female Tac2 / mice exhibit delayed sexual maturation, with abnormal cycling and reduced fertility in adulthood. However, by postnatal day 94, Tac2 / females recover estrous cyclicity and exhibit normal physiological levels of LH and FSH. The finding of delayed puberty in female Tac2 / mice contrasts with female Tacr3 / mice, which show normal timing of puberty. However, the reproductive effects of Tac2 ablation in female mice closely recapitulate the reproductive deficits, and cycle recovery, observed in women with disrupted NKB signaling. These observations support the argument of True et al (25) that NKB is necessary for proper timing of sexual maturation, but not for sustaining normal adult reproductive function once it begins. Curiously, the re-

Identification of the genes regulated by Wnt-4, a critical signal for commitment of the ovary

The indifferent mammalian embryonic gonad generates an ovary or testis, but the factors involved are still poorly known. The Wnt-4 signal represents one critical female determinant, since its absence leads to partial female-to-male sex reversal in mouse, but its signalling is as well implicated in the testis development. We used the Wnt-4 deficient mouse as a model to identify candidate gonadogenesis genes, and found that the Notum, Phlda2, Runx-1 and Msx1 genes are typical of the wild-type ovary and the Osr2, Dach2, Pitx2 and Tacr3 genes of the testis. Strikingly, the expression of these latter genes becomes reversed in the Wnt-4 knock-out ovary, suggesting a role in ovarian development. We identified the transcription factor Runx-1 as a Wnt-4 signalling target gene, since it is expressed in the ovary and is reduced upon Wnt-4 knock-out. Consistent with this, introduction of the Wnt-4 signal into early ovary cells ex vivo induces Runx-1 expression, while conversely Wnt-4 expression is down-regulated in the absence of Runx-1. We conclude that the Runx-1 gene can be a Wnt-4 signalling target, and that Runx-1 and Wnt-4 are mutually interdependent in their expression. The changes in gene expression due to the absence of Wnt-4 in gonads reflect the sexually dimorphic role of this signal and its complex gene network in mammalian gonad development.