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1.
Expert Opin Ther Pat ; 34(1-2): 71-81, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38573177

RESUMO

INTRODUCTION: The neuropeptide relaxin-3/RXFP3 system belongs to the relaxin/insulin superfamily and is involved in many important physiological processes, such as stress responses, appetite control, and motivation for reward. Although relaxin-3 is the endogenous agonist for RXFP3, it can also bind to and activate RXFP1 and RXFP4. Consequently, research has been focused on the development of RXFP3-specific peptides and small-molecule ligands to validate the relaxin-3/RXFP3 system as a novel drug target. AREAS COVERED: This review provides an overview of patents on the relaxin-3/RXFP3 system covering ligand development and pharmacological studies since 2003. Related patents and literature reports were obtained from established sources including SciFinder, Google Patents, and Espacenet for patents and SciFinder, PubMed, and Google Scholar for literature reports. EXPERT OPINION: There has been an increasing amount of patent activities around relaxin-3/RXFP3, highlighting the importance of this novel neuropeptide system for drug discovery. The development of relaxin-3 derived peptides and small-molecule modulators, as well as behavioral studies in rodents, have shown that the relaxin-3/RXFP3 system is a promising drug target for treating various metabolic and neuropsychiatric diseases including obesity, anxiety, and alcohol addiction.


Assuntos
Neuropeptídeos , Relaxina , Humanos , Receptores Acoplados a Proteínas G/metabolismo , Relaxina/metabolismo , Patentes como Assunto , Insulina/metabolismo , Receptores de Peptídeos/agonistas , Receptores de Peptídeos/metabolismo
4.
Mol Pharmacol ; 105(5): 359-373, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38458773

RESUMO

Dual amylin and calcitonin receptor agonists (DACRAs) show promise as efficacious therapeutics for treatment of metabolic disease, including obesity. However, differences in efficacy in vivo have been observed for individual DACRAs, indicating that detailed understanding of the pharmacology of these agents across target receptors is required for rational drug development. To date, such understanding has been hampered by lack of direct, subtype-selective, functional assays for the amylin receptors (AMYRs). Here, we describe the generation of receptor-specific assays for recruitment of Venus-tagged Gs protein through fusion of luciferase to either the human calcitonin receptor (CTR), human receptor activity-modifying protein (RAMP)-1, RAMP1 (AMY1R), human RAMP2 (AMY2R), or human RAMP3 (AMY3R). These assays revealed a complex pattern of receptor activation by calcitonin, amylin, or DACRA peptides that was distinct at each receptor subtype. Of particular note, although both of the CT-based DACRAs, sCT and AM1784, displayed relatively similar behaviors at CTR and AMY1R, they generated distinct responses at AMY2R and AMY3R. These data aid the rationalization of in vivo differences in response to DACRA peptides in rodent models of obesity. Direct assessment of the pharmacology of novel DACRAs at AMYR subtypes is likely to be important for development of optimized therapeutics for treatment of metabolic diseases. SIGNIFICANCE STATEMENT: Amylin receptors (AMYRs) are important obesity targets. Here we describe a novel assay that allows selective functional assessment of individual amylin receptor subtypes that provides unique insight into the pharmacology of potential therapeutic ligands. Direct assessment of the pharmacology of novel agonists at AMYR subtypes is likely to be important for development of optimized therapeutics for treatment of metabolic diseases.


Assuntos
Doenças Metabólicas , Neuropeptídeos , Humanos , Receptores da Calcitonina/metabolismo , Proteínas Modificadoras da Atividade de Receptores , Receptores de Polipeptídeo Amiloide de Ilhotas Pancreáticas , Polipeptídeo Amiloide das Ilhotas Pancreáticas , Receptores de Peptídeos/metabolismo , Proteínas de Membrana/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular , Obesidade
5.
Clin Nucl Med ; 49(5): 454-456, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38465961

RESUMO

ABSTRACT: Extravasation of the radiopharmaceutical during peptide receptor radionuclide therapy infusion is an unwanted infrequently reported event. We present the case of a 74-year old woman with a neuroendocrine tumor who was referred for peptide receptor radionuclide therapy. During intravenous infusion of 7.4 GBq [ 177 Lu]Lu-HA-DOTATATE in the upper right arm, extravasation of the radiopharmaceutical occurred through a displaced intravenous catheter. Planar scintigraphy showed pooling of radioactivity in the right upper arm. After 24 hours, the swelling in the arm was decreased; however, erythema was increased. One week later, symptoms had disappeared, and the patient did not experience any complications during follow-up of 11 months.


Assuntos
Lutécio , Tumores Neuroendócrinos , Compostos Organometálicos , Tomografia por Emissão de Pósitrons , Cintilografia , Feminino , Humanos , Idoso , Compostos Radiofarmacêuticos , Octreotida/efeitos adversos , Radioisótopos , Tumores Neuroendócrinos/diagnóstico por imagem , Tumores Neuroendócrinos/radioterapia , Receptores de Peptídeos , Compostos Organometálicos/efeitos adversos
6.
Mol Biol Evol ; 41(4)2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38518286

RESUMO

Post-mating responses play a vital role in successful reproduction across diverse species. In fruit flies, sex peptide binds to the sex peptide receptor, triggering a series of post-mating responses. However, the origin of sex peptide receptor predates the emergence of sex peptide. The evolutionary origins of the interactions between sex peptide and sex peptide receptor and the mechanisms by which they interact remain enigmatic. In this study, we used ancestral sequence reconstruction, AlphaFold2 predictions, and molecular dynamics simulations to study sex peptide-sex peptide receptor interactions and their origination. Using AlphaFold2 and long-time molecular dynamics simulations, we predicted the structure and dynamics of sex peptide-sex peptide receptor interactions. We show that sex peptide potentially binds to the ancestral states of Diptera sex peptide receptor. Notably, we found that only a few amino acid changes in sex peptide receptor are sufficient for the formation of sex peptide-sex peptide receptor interactions. Ancestral sequence reconstruction and molecular dynamics simulations further reveal that sex peptide receptor interacts with sex peptide through residues that are mostly involved in the interaction interface of an ancestral ligand, myoinhibitory peptides. We propose a potential mechanism whereby sex peptide-sex peptide receptor interactions arise from the preexisting myoinhibitory peptides-sex peptide receptor interface as well as early chance events both inside and outside the preexisting interface that created novel sex peptide-specific sex peptide-sex peptide receptor interactions. Our findings provide new insights into the origin and evolution of sex peptide-sex peptide receptor interactions and their relationship with myoinhibitory peptides-sex peptide receptor interactions.


Assuntos
Proteínas de Drosophila , Drosophila melanogaster , Animais , Drosophila melanogaster/metabolismo , Proteínas de Drosophila/metabolismo , Peptídeos/química , Drosophila/metabolismo , Receptores de Peptídeos/genética , Receptores de Peptídeos/metabolismo
7.
J Nucl Med ; 65(3): 409-415, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38428966

RESUMO

Posttreatment imaging of γ-emissions after peptide receptor radionuclide therapy (PRRT) can be used to perform quantitative dosimetry as well as assessment response using qualitative measures. We aimed to assess the impact of qualitative posttreatment imaging on the management of patients undergoing PRRT. Methods: In this retrospective study, we evaluated 100 patients with advanced well-differentiated neuroendocrine tumors undergoing PRRT, who had posttreatment SPECT/CT imaging at 24 h. First, we evaluated the qualitative assessment of response at each cycle. Then using a chart review, we determined the impact on management from the posttreatment imaging. The changes in management were categorized as major or minor, and the cycles at which these changes occurred were noted. Additionally, tumor grade was also evaluated. Results: Of the 100 sequential patients reviewed, most (80% after cycle 2, 79% after cycle 3, and 73% after cycle 4) showed qualitatively stable disease during PRRT. Management changes were observed in 27% (n = 27) of patients; 78% of those (n = 21) were major, and 30% (n = 9) were minor. Most treatment changes occurred after cycle 2 (33% major, 67% minor) and cycle 3 (62% major, 33% minor). Higher tumor grade correlated with increased rate of changes in management (P = 0.006). Conclusion: In this retrospective study, qualitative analysis of posttreatment SPECT/CT imaging informed changes in management in 27% of patients. Patients with higher-grade tumors had a higher rate of change in management, and most of the management changes occurred after cycles 2 and 3. Incorporating posttreatment imaging into standard PRRT workflows could potentially enhance patient management.


Assuntos
Tumores Neuroendócrinos , Octreotida , Humanos , Octreotida/uso terapêutico , Estudos Retrospectivos , Tumores Neuroendócrinos/diagnóstico por imagem , Tumores Neuroendócrinos/radioterapia , Tumores Neuroendócrinos/patologia , Radioisótopos , Receptores de Peptídeos
8.
J Med Chem ; 67(6): 4442-4462, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38502780

RESUMO

Relaxin H2 is a clinically relevant peptide agonist for relaxin family peptide receptor 1 (RXFP1), but a combination of this hormone's short plasma half-life and the need for injectable delivery limits its therapeutic potential. We sought to overcome these limitations through the development of a potent small molecule (SM) RXFP1 agonist. Although two large SM HTS campaigns failed in identifying suitable hit series, we uncovered novel chemical space starting from the only known SM RXFP1 agonist series, represented by ML290. Following a design-make-test-analyze strategy based on improving early dose to man ranking, we discovered compound 42 (AZ7976), a highly selective RXFP1 agonist with sub-nanomolar potency. We used AZ7976, its 10 000-fold less potent enantiomer 43 and recombinant relaxin H2 to evaluate in vivo pharmacology and demonstrate that AZ7976-mediated heart rate increase in rats was a result of RXFP1 agonism. As a result, AZ7976 was selected as lead for continued optimization.


Assuntos
Relaxina , Humanos , Masculino , Ratos , Animais , Relaxina/farmacologia , Receptores Acoplados a Proteínas G/agonistas , Receptores de Peptídeos/agonistas
9.
J Med Chem ; 67(6): 4419-4441, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38502782

RESUMO

Optimization of the highly potent and selective, yet metabolically unstable and poorly soluble hRXFP1 agonist AZ7976 led to the identification of the clinical candidate, AZD5462. Assessment of RXFP1-dependent cell signaling demonstrated that AZD5462 activates a highly similar panel of downstream pathways as relaxin H2 but does not modulate relaxin H2-mediated cAMP second messenger responsiveness. The therapeutic potential of AZD5462 was assessed in a translatable cynomolgus monkey heart failure model. Following 8 weeks of treatment with AZD5462, robust improvements in functional cardiac parameters including LVEF were observed at weeks 9, 13, and 17 without changes in heart rate or mean arterial blood pressure. AZD5462 was well tolerated in both rat and cynomolgus monkey and has successfully completed phase I studies in healthy volunteers. In summary, AZD5462 is a small molecule pharmacological mimetic of relaxin H2 signaling at RXFP1 and holds promise as a potential therapeutic approach to treat heart failure patients.


Assuntos
Insuficiência Cardíaca , Relaxina , Humanos , Ratos , Animais , Relaxina/farmacologia , Receptores Acoplados a Proteínas G/metabolismo , Macaca fascicularis/metabolismo , Receptores de Peptídeos/metabolismo , Insuficiência Cardíaca/tratamento farmacológico
10.
Clin Nucl Med ; 49(4): e161-e163, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38427960

RESUMO

ABSTRACT: Gastrinomas with predilection for the adult male population are located in the gastrinoma triangle (>90%). Primary hepatic gastrinoma especially in pediatric population is very rare. Peptide receptor radionuclide therapy has shown benefit in metastatic gastroenteropancreatic neuroendocrine tumors (NETs) with an increasing interest in expanding its role as neoadjuvant treatment modality to improve the surgical candidature in inoperable NETs. There is currently no literature supporting its role in the pediatric NET patients. We present a rare case of a young boy with primary hepatic gastrinoma where 177Lu-based peptide receptor radionuclide therapy in the neoadjuvant setting contributed to his final disease-free status.


Assuntos
Gastrinoma , Segunda Neoplasia Primária , Tumores Neuroendócrinos , Neoplasias Pancreáticas , Adulto , Humanos , Criança , Masculino , Gastrinoma/diagnóstico por imagem , Gastrinoma/radioterapia , Terapia Neoadjuvante , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/radioterapia , Receptores de Peptídeos
11.
Endocr Relat Cancer ; 31(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38329269

RESUMO

We observed that some patients with well-differentiated neuroendocrine tumors (NET) who received peptide receptor radionuclide therapy (PRRT) with Lutetium-177 (177Lu) DOTATATE developed rapid disease progression with biopsy-proven histologic transformation to neuroendocrine carcinoma (NEC), an outcome that has not been previously described. Therefore, we conducted a retrospective review of all patients with well-differentiated G1-G2 NET who received at least one cycle of PRRT with (177Lu) DOTATATE at our center from January 2019 to December 2020. Among 152 patients, we identified 7 patients whose NET transformed to NEC. Median time from start of PRRT to transformation was 8.2 months (range: 2.6-14.4 months). All patients whose tumors underwent transformation had pancreatic tail as the primary site and had prior chemotherapy with temozolomide. No differences in the incidence of transformation were observed according to gender, race, original tumor grade, or number of prior therapies. Six patients received treatment with platinum and etoposide after transformation with two patients having partial response as best response. All patients with transformation died from progressive disease with median overall survival (OS) after transformation of 3.3 months (95% CI 2.1-4.4). Molecular testing of transformed NEC identified mutation(s) in TP53 and/or ATM in all cases. Transformation of NET to NEC following PRRT is associated with aggressive course and dismal prognosis. Patients with pancreatic tail as the primary site who had prior therapy with temozolomide may be at a higher risk. Further investigation is necessary to determine the best treatment sequence in this patient population.


Assuntos
Carcinoma Neuroendócrino , Lutécio , Tumores Neuroendócrinos , Radioisótopos , Humanos , Tumores Neuroendócrinos/tratamento farmacológico , Tumores Neuroendócrinos/radioterapia , Temozolomida , Carcinoma Neuroendócrino/tratamento farmacológico , Carcinoma Neuroendócrino/radioterapia , Biópsia , Receptores de Peptídeos
12.
Am J Hum Genet ; 111(3): 456-472, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38367619

RESUMO

The impact of tobacco exposure on health varies by race and ethnicity and is closely tied to internal nicotine dose, a marker of carcinogen uptake. DNA methylation is strongly responsive to smoking status and may mediate health effects, but study of associations with internal dose is limited. We performed a blood leukocyte epigenome-wide association study (EWAS) of urinary total nicotine equivalents (TNEs; a measure of nicotine uptake) and DNA methylation measured using the MethylationEPIC v1.0 BeadChip (EPIC) in six racial and ethnic groups across three cohort studies. In the Multiethnic Cohort Study (discovery, n = 1994), TNEs were associated with differential methylation at 408 CpG sites across >250 genomic regions (p < 9 × 10-8). The top significant sites were annotated to AHRR, F2RL3, RARA, GPR15, PRSS23, and 2q37.1, all of which had decreasing methylation with increasing TNEs. We identified 45 novel CpG sites, of which 42 were unique to the EPIC array and eight annotated to genes not previously linked with smoking-related DNA methylation. The most significant signal in a novel gene was cg03748458 in MIR383;SGCZ. Fifty-one of the 408 discovery sites were validated in the Singapore Chinese Health Study (n = 340) and the Southern Community Cohort Study (n = 394) (Bonferroni corrected p < 1.23 × 10-4). Significant heterogeneity by race and ethnicity was detected for CpG sites in MYO1G and CYTH1. Furthermore, TNEs significantly mediated the association between cigarettes per day and DNA methylation at 15 sites (average 22.5%-44.3% proportion mediated). Our multiethnic study highlights the transethnic and ethnic-specific methylation associations with internal nicotine dose, a strong predictor of smoking-related morbidities.


Assuntos
MicroRNAs , Fumantes , Humanos , Nicotina , Epigênese Genética/genética , Epigenoma , Estudos de Coortes , Estudos Prospectivos , Estudo de Associação Genômica Ampla , Metilação de DNA/genética , Ilhas de CpG/genética , Receptores de Peptídeos/genética , Receptores Acoplados a Proteínas G/genética
13.
Cell Commun Signal ; 22(1): 140, 2024 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-38378560

RESUMO

Hostile microenvironment of cancer cells provoke a stressful condition for endoplasmic reticulum (ER) and stimulate the expression and secretion of ER chaperones, leading to tumorigenic effects. However, the molecular mechanism underlying these effects is largely unknown. In this study, we reveal that the last four residues of ER chaperones, which are recognized by KDEL receptor (KDELR), is required for cell proliferation and migration induced by secreted chaperones. By combining proximity-based mass spectrometry analysis, split venus imaging and membrane yeast two hybrid assay, we present that EGF receptor (EGFR) may be a co-receptor for KDELR on the surface. Prior to ligand addition, KDELR spontaneously oligomerizes and constantly undergoes recycling near the plasma membrane. Upon KDEL ligand binding, the interactions of KDELR with itself and with EGFR increase rapidly, leading to augmented internalization of KDELR and tyrosine phosphorylation in the C-terminus of EGFR. STAT3, which binds the phosphorylated tyrosine motif on EGFR, is subsequently activated by EGFR and mediates cell growth and migration. Taken together, our results suggest that KDELR serves as a bona fide cell surface receptor for secreted ER chaperones and transactivates EGFR-STAT3 signaling pathway.


Assuntos
Receptores ErbB , Receptores de Peptídeos , Transdução de Sinais , Humanos , Ligantes , Receptores ErbB/metabolismo , Chaperonas Moleculares/metabolismo , Proliferação de Células , Tirosina , Fator de Transcrição STAT3/metabolismo
14.
Nature ; 626(7997): 128-135, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38233523

RESUMO

The assembly and specification of synapses in the brain is incompletely understood1-3. Latrophilin-3 (encoded by Adgrl3, also known as Lphn3)-a postsynaptic adhesion G-protein-coupled receptor-mediates synapse formation in the hippocampus4 but the mechanisms involved remain unclear. Here we show in mice that LPHN3 organizes synapses through a convergent dual-pathway mechanism: activation of Gαs signalling and recruitment of phase-separated postsynaptic protein scaffolds. We found that cell-type-specific alternative splicing of Lphn3 controls the LPHN3 G-protein-coupling mode, resulting in LPHN3 variants that predominantly signal through Gαs or Gα12/13. CRISPR-mediated manipulation of Lphn3 alternative splicing that shifts LPHN3 from a Gαs- to a Gα12/13-coupled mode impaired synaptic connectivity as severely as the overall deletion of Lphn3, suggesting that Gαs signalling by LPHN3 splice variants mediates synapse formation. Notably, Gαs-coupled, but not Gα12/13-coupled, splice variants of LPHN3 also recruit phase-transitioned postsynaptic protein scaffold condensates, such that these condensates are clustered by binding of presynaptic teneurin and FLRT ligands to LPHN3. Moreover, neuronal activity promotes alternative splicing of the synaptogenic Gαs-coupled variant of LPHN3. Together, these data suggest that activity-dependent alternative splicing of a key synaptic adhesion molecule controls synapse formation by parallel activation of two convergent pathways: Gαs signalling and clustered phase separation of postsynaptic protein scaffolds.


Assuntos
Processamento Alternativo , Receptores Acoplados a Proteínas G , Receptores de Peptídeos , Sinapses , Animais , Camundongos , Processamento Alternativo/genética , Subunidades alfa G12-G13 de Proteínas de Ligação ao GTP , Subunidades alfa Gs de Proteínas de Ligação ao GTP , Ligantes , Receptores Acoplados a Proteínas G/deficiência , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Peptídeos/deficiência , Receptores de Peptídeos/genética , Receptores de Peptídeos/metabolismo , Sinapses/metabolismo , Transdução de Sinais
15.
Clin J Oncol Nurs ; 28(1): 79-87, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38252861

RESUMO

BACKGROUND: Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) are a diverse family of cancers that occur within the gastrointestinal tract and pancreas. Peptide receptor radionuclide therapy (PRRT) via 177Lu-DOTATATE is a newer therapeutic option for certain patients with somatostatin receptor-positive GEP-NETs. OBJECTIVES: This review informs on how oncology nurses treating patients with GEP-NETs receiving PRRT using 177Lu-DOTATATE can facilitate care. METHODS: Guidance on the monitoring, management, and care of patients undergoing PRRT for GEP-NETs was developed based on published literature and the nursing experience of the authors. A case study is summarized to highlight key concepts. FINDINGS: Oncology nurses provide assessment, education, direct care, and emotional support when caring for patients with GEP-NETs receiving PRRT with 177Lu-DOTATATE. As the treatment landscape evolves, so too will these roles and responsibilities.


Assuntos
Neoplasias Intestinais , Tumores Neuroendócrinos , Octreotida/análogos & derivados , Compostos Organometálicos , Neoplasias Pancreáticas , Neoplasias Gástricas , Humanos , Tumores Neuroendócrinos/radioterapia , Receptores de Peptídeos , Radioisótopos
16.
J Nucl Med ; 65(2): 258-263, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38212066

RESUMO

A mesenteric mass (MM), characterized by fibrotic reaction, is present in most small-intestinal neuroendocrine tumors (SI-NETs). 177Lu-DOTATATE peptide receptor radionuclide therapy (PRRT) has shown its efficacy in patients with progressive SI-NETs. However, because of specific tissue characteristics of desmoplastic MMs, we hypothesize that these lesions may be refractory to 177Lu-DOTATATE PRRT. Methods: From the national French Groupe d'étude des Tumeurs Endocrines database, we identified patients with an advanced SI-NET and a MM (≥2 cm with a retractile aspect) of a SI-NET treated by at least 1 course of 177Lu-DOTATATE PRRT. The primary endpoint was a MM objective response rate (ORR) of less than 5%. Secondary endpoints were metabolic response, MM-related safety, and clinical response, as well as MM progression-free survival (PFS) and non-MM PFS. Results: In total, 52 patients were included. The MM ORR was 4% (n = 2), and the non-MM ORR was 8% (n = 4). No patient had a MM metabolic response, and the non-MM metabolic response rate was 12% (n = 6). Among the 26 patients with baseline MM-related symptoms, 46% had a clinical response. Four patients presented with gastrointestinal complications during PRRT. The median MM-related PFS was not reached, and the non-MM PFS was 50.3 mo (95% CI, 38.2-61.7 mo). Conclusion: This study confirms that 177Lu-DOTATATE PRRT does not lead to morphologic response on MMs (ORR < 5%). However, it allows MM stability, with few MM-related side effects, and has a relevant impact on MM-related symptoms.


Assuntos
Neoplasias das Glândulas Endócrinas , Neoplasias Intestinais , Tumores Neuroendócrinos , Compostos Organometálicos , Tomografia por Emissão de Pósitrons , Cintilografia , Humanos , Tumores Neuroendócrinos/metabolismo , Resultado do Tratamento , Octreotida/efeitos adversos , Neoplasias Intestinais/radioterapia , Neoplasias Intestinais/tratamento farmacológico , Radioisótopos/uso terapêutico , Receptores de Peptídeos/metabolismo , Compostos Organometálicos/efeitos adversos
17.
Theranostics ; 14(3): 940-953, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38250038

RESUMO

A growing body of literature reports on the combined use of peptide receptor radionuclide therapy (PRRT) with other anti-tumuor therapies in order to anticipate synergistic effects with perhaps increased safety issues. Combination treatments to enhance PRRT outcome are based on improved tumour perfusion, upregulation of somatostatin receptors (SSTR), radiosensitization with DNA damaging agents or targeted therapies. Several Phase 1 or 2 trials are currently recruiting patients in combined regimens. The combination of PRRT with cytotoxic chemotherapy, capecitabine and temozolomide (CAPTEM), seems to become clinically useful especially in pancreatic neuroendocrine tumours (pNETs) with acceptable safety profile. Neoadjuvant PRRT prior to surgery, PRRT combinations of intravenous and intraarterial routes of application, combinations of PRRT with differently radiolabelled (alpha, beta, Auger) SSTR-targeting agonists and antagonists, inhibitors of immune checkpoints (ICIs), poly (ADP-ribose) polymerase-1 (PARP1i), tyrosine kinase (TKI), DNA-dependent protein kinase, ribonucleotide reductase or DNA methyltransferase (DMNT) are tested in currently ongoing clinical trials. The combination with [131I]I-MIBG in rare NETs (such as paraganglioma, pheochromocytoma) and new non-SSTR-targeting radioligands are used in the personalization process of treatment. The present review will provide an overview of the current status of ongoing PRRT combination treatments.


Assuntos
Neoplasias das Glândulas Suprarrenais , Tumores Neuroendócrinos , Humanos , Tumores Neuroendócrinos/tratamento farmacológico , Tumores Neuroendócrinos/radioterapia , Radioisótopos do Iodo , DNA , Receptores de Peptídeos
18.
Proc Natl Acad Sci U S A ; 121(3): e2312380120, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38215185

RESUMO

Across internally fertilising species, males transfer ejaculate proteins that trigger wide-ranging changes in female behaviour and physiology. Much theory has been developed to explore the drivers of ejaculate protein evolution. The accelerating availability of high-quality genomes now allows us to test how these proteins are evolving at fine taxonomic scales. Here, we use genomes from 264 species to chart the evolutionary history of Sex Peptide (SP), a potent regulator of female post-mating responses in Drosophila melanogaster. We infer that SP first evolved in the Drosophilinae subfamily and has since followed markedly different evolutionary trajectories in different lineages. Outside of the Sophophora-Lordiphosa, SP exists largely as a single-copy gene with independent losses in several lineages. Within the Sophophora-Lordiphosa, the SP gene family has repeatedly and independently expanded. Up to seven copies, collectively displaying extensive sequence variation, are present in some species. Despite these changes, SP expression remains restricted to the male reproductive tract. Alongside, we document considerable interspecific variation in the presence and morphology of seminal microcarriers that, despite the critical role SP plays in microcarrier assembly in D. melanogaster, appears to be independent of changes in the presence/absence or sequence of SP. We end by providing evidence that SP's evolution is decoupled from that of its receptor, Sex Peptide Receptor, in which we detect no evidence of correlated diversifying selection. Collectively, our work describes the divergent evolutionary trajectories that a novel gene has taken following its origin and finds a surprisingly weak coevolutionary signal between a supposedly sexually antagonistic protein and its receptor.


Assuntos
Proteínas de Drosophila , Drosophila melanogaster , Animais , Feminino , Masculino , Evolução Biológica , Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Proteínas de Drosophila/metabolismo , Peptídeos/genética , Peptídeos/metabolismo , Receptores de Peptídeos/genética , Receptores de Peptídeos/metabolismo , Reprodução/genética , Comportamento Sexual Animal
19.
J Nucl Med ; 65(2): 228-235, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38164592

RESUMO

Metastatic insulinoma is a rare malignant neuroendocrine tumor characterized by inappropriate insulin secretion, resulting in life-threatening hypoglycemia, which is often difficult to treat. There is currently very limited information about the efficacy of peptide receptor radionuclide therapy (PRRT) for clinical control of hypoglycemia. The aim of this long-term retrospective study was to evaluate the therapeutic efficacy of PRRT for improving hypoglycemia, to evaluate the change of medication after PRRT, and to calculate progression-free survival (PFS) and overall survival (OS). Methods: Inclusion criteria were histologically proven somatostatin receptor-positive metastatic malignant insulinoma and at least 2 cycles of [90Y]Y-DOTATOC or [177Lu]Lu-DOTATOC therapy from early 2000 to early 2022. A semiquantitative scoring system was used to quantify the severity and frequency of hypoglycemic episodes under background antihypoglycemic therapy (somatostatin analog, diazoxide, everolimus, corticosteroids): score 0, no hypoglycemic episodes; score 1, hypoglycemic events requiring additional conservative treatment with optimization of nutrition; score 2, severe hypoglycemia necessitating hospitalization and combined medication or history of hypoglycemic coma. Hypoglycemic score before and after PRRT was analyzed. Time of benefit was defined as a time range of fewer hypoglycemic episodes in the observation period than at baseline. Information on antihypoglycemic medication before and after therapy, PFS, and OS was recorded. Results: Twenty-six of 32 patients with a total of 106 [90Y]Y-DOTATOC/[177Lu]Lu-DOTATOC cycles were included. The average observation period was 21.5 mo (range, 2.3-107.4 mo). Before therapy, 81% (n = 21) of the patients had a hypoglycemia score of 2 and 19% (n = 5) had a score of 1. After PRRT, 81% of patients (n = 21) had a decreased score, and the remaining 5 patients showed a stable situation. There was temporary worsening of hypoglycemia just after injection of [90Y]Y-DOTATOC/[177Lu]Lu-DOTATOC in 19% of patients. The average time of benefit in the observation period was 17.2 mo (range, 0-70.2 mo). Antihypoglycemic medication reduction was achieved in 58% (n = 15) of patients. The median OS and PFS after the start of PRRT were 19.7 mo (95% CI, 6.5-32.9 mo) and 11.7 mo (95% CI, 4.9-18.5 mo), respectively. Conclusion: To our knowledge, our study included the largest cohort of patients with malignant insulinoma to be evaluated. Long-lasting symptom control and reduction of antihypoglycemic medications were shown in most patients after late-line PRRT.


Assuntos
Hipoglicemia , Insulinoma , Tumores Neuroendócrinos , Compostos Organometálicos , Neoplasias Pancreáticas , Humanos , Estudos Retrospectivos , Insulinoma/radioterapia , Resultado do Tratamento , Tumores Neuroendócrinos/radioterapia , Tumores Neuroendócrinos/tratamento farmacológico , Octreotida/efeitos adversos , Neoplasias Pancreáticas/radioterapia , Neoplasias Pancreáticas/tratamento farmacológico , Radioisótopos , Hipoglicemia/induzido quimicamente , Hipoglicemia/tratamento farmacológico , Receptores de Peptídeos/química , Hipoglicemiantes , Compostos Organometálicos/uso terapêutico
20.
BMJ Case Rep ; 17(1)2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38272512

RESUMO

Congenital hypogonadotropic hypogonadism (CHH) is a genetically and clinically diverse disorder encompassing Kallmann syndrome (KS) and normosmic CHH (nCHH). Although mutations in numerous genes account for nearly 50% of CHH cases, a significant portion remains genetically uncharacterized. While most mutations follow the traditional Mendelian inheritance patterns, evidence suggests oligogenic interactions between CHH genes, acting as modifier genes to explain variable expressivity and incomplete penetrance associated with certain mutations.In this study, the proband presented with nCHH, while his son exhibited KS. We employed whole-exome sequencing (WES) to investigate the genetic differences between the two, and Sanger sequencing was used to validate the results obtained from WES.Genetic analysis revealed that both the proband and his son harboured a mutation in FGFR1 gene. Notably, an additional rare mutation in PROKR2 gene was exclusively identified in the son, which suggests the cause of the phenotypic difference between KS and nCHH.


Assuntos
Hipogonadismo , Síndrome de Kallmann , Humanos , Síndrome de Kallmann/genética , Mutação de Sentido Incorreto , Hipogonadismo/genética , Mutação , Família , Receptores de Peptídeos/genética , Receptores Acoplados a Proteínas G/genética , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética
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