Search Results (25)

Menin, the product of the Multiple Endocrine Neoplasia type 1 (MEN1) gene, is a scaffold protein, the lack of which leads to the development of a tumor syndrome primarily affecting endocrine organs. Although it is classified as an oncosuppressor, menin is a ubiquitous protein whose expression is also abundant in non-endocrine tissues such as the central nervous system, where knowledge of menin’s role still remains limited. In this article, we aim to draw attention to an underestimated clinical aspect of MEN1 syndrome, i.e., the psychological/psychiatric manifestations, in which menin deficiency could have an important function. Our aim is to highlight that a multidisciplinary team caring for patients with MEN1 throughout their lives should include professionals such as psychologists and psychiatrists in order to better manage any mental illness associated with the syndrome and to further improve the patient’s quality of life. Full article

Pancreatic neuroendocrine tumors (pNETs) are rare malignancies, accounting for 1–2% of pancreatic cancers, with an incidence of ≤1 case per 100,000 individuals annually. Originating from pancreatic endocrine cells, pNETs display significant clinical and biological heterogeneity. Traditional classification based on proliferative grading does not fully capture the complex mechanisms involved, such as oxidative stress, mitochondrial dysfunction, and tumor-associated macrophage infiltration. Recent advances in molecular profiling have revealed key oncogenic drivers, including MEN1 (menin 1), DAXX (death domain–associated protein), ATRX (alpha thalassemia/mental retardation syndrome X-linked), CDKN1B (cyclin-dependent kinase inhibitor 1B) mutations, chromatin remodeling defects, and dysregulation of the mTOR pathway. Somatostatin receptors, particularly SSTR2, play a central role in tumor biology and serve as important prognostic markers, enabling the use of advanced diagnostic imaging (e.g., Gallium-68 DOTATATE PET/CT) and targeted therapies like somatostatin analogs and peptide receptor radionuclide therapy (PRRT). Established biomarkers such as Chromogranin A and the Ki-67 proliferation index remain vital for diagnosis and prognosis, while emerging markers, like circulating tumor DNA and microRNAs, show promise for enhancing disease monitoring and diagnostic accuracy. This review summarizes the molecular landscape of pNETs and highlights genomic, transcriptomic, proteomic, and epigenomic factors that support the identification of novel diagnostic, prognostic, and therapeutic biomarkers, ultimately advancing personalized treatment strategies. Full article

The aberrant localization of the mutated nucleophosmin (NPM1) protein in the cytoplasm is the hallmark of the development of acute myeloid leukemia (AML); the gene, located in the nucleolus, codes for a protein that normally shuttles between the nucleus and the cytoplasm of the normal hematopoietic cells. Patients harboring NPM1 mutations are diagnosed as having NPM1-mutated AMLs, which are types of leukemia with distinct clinical and laboratory characteristics. The essential diagnostics for investigating NPM1-mutated AMLs, the interactions with concomitant mutations affecting prognosis and the therapeutic interventions that the treatment of such patients requires are discussed in this review. Novel investigational agents in current clinical trials are also highlighted, along with the roles of exportin 1 (XPO1), menin-KMT2A inhibitors and immunotherapy in NPM1-mutated AMLs. This review focuses on critically evaluating the available data and aims to reveal the secrets of NPM1-mutated AMLs. Full article

Background: Multiple endocrine neoplasia type 1 (MEN1)-related primary hyperparathyroidism (MPHPT) belongs to genetic PHPT that accounts for 10% of all PHPT cases, being considered the most frequent hereditary PHPT (less than 5% of all PHPT). Objective: We aimed to provide an updated clinical perspective with a double purpose: to highlight the clinical features in MPHPT, particularly, the bone health assessment, as well as the parathyroidectomy (PTx) impact. Methods: A comprehensive review of the latest 5-year, English-published, PubMed-accessed original studies. Results: The sample-based analysis (n = 17 studies) enrolled 2426 subjects (1720 with MPHPT). The study design was retrospective, except for one prospective and one case–control study. The maximum number of patients per study was of 517. Female predominance (an overall female-to-male ratio of 1.139) was confirmed (except for three studies). Age at MPHPT diagnosis (mean/median per study): 28.7 to 43.1 years; age at PTx: 32 to 43.5 years. Asymptomatic PHPT was reported in 38.3% to 67% of MPHPT. Mean total calcium varied between 1.31 and 2.88 mmol/L and highest PTH was of 317.2 pg/mL. Two studies reported similar PTH and calcaemic levels in MPHPT vs. sporadic PHPT, while another found higher values in MPHPT. Symptomatic vs. asymptomatic patients with MPHPT had similar PTH and serum calcium levels (n = 1). Osteoporosis (n = 8, N = 723 with MPHPT) was reported in 10% to 55.5% of cases, osteopenia in 5.88% to 43.9% (per study); overall fracture rate was 10% (of note, one study showed 0%). Lower bone mineral density (BMD) at DXA (n = 4) in MPHPT vs. sporadic PHPT/controls was found by some studies (n = 3, and only a single study provided third distal radius DXA-BMD assessment), but not all (n = 1). Post-PTx DXA (n = 3, N = 190 with MPHPT) showed a BMD increase (e.g., +8.5% for lumbar spine, +2.1% for total hip, +4.3% for femoral neck BMD); however, post-operatory, BMD remains lower than controls. Trabecular bone score (TBS) analysis (n = 2, N = 142 with MPHPT vs. 397 with sporadic PHPT) showed a higher prevalence of reduced TBS (n = 1) or similar (n = 1). PTx analysis in MPHPT (n = 14): rate of subtotal PTx of 39% to 66.7% (per study) or less than subtotal PTx of 46.9% (n = 1). Post-PTx complications: persistent PHPT (5.6% to 25%), recurrent PHPT (16.87% to 30%, with the highest re-operation rate of 71% in one cohort); hypoparathyroidism (12.4% to 41.7%). Genetic analysis pointed out a higher risk of post-PTx recurrence in exon 10 MEN1 pathogenic variant. Post-PTx histological exam showed a multi-glandular disease in 40% to 52.1% of MPHPT, and a parathyroid carcinoma prevalence of 1%. Conclusions: MPHPT remains a challenging ailment amid a multi-layered genetic syndrome. Current data showed a lower age at MPHPT diagnosis and surgery than found in general population, and a rate of female predominance that is lower than seen in sporadic PHPT cases, but higher than known, for instance, in MEN2. The bone involvement showed heterogeneous results, more consistent for a lower BMD, but not necessarily for a lower TBS vs. controls. PTx involves a rather high rate of recurrence, persistence and redo surgery. About one out of ten patients with MPHPT might have a prevalent fracture and PTx improves the overall bone health, but seems not to restore it to the general population level, despite the young age of the subjects. This suggests that non-parathyroid components and potentially menin protein displays negative bone effects in MEN1. Full article

Menin (MEN1) is a well-recognized powerful tumor promoter in acute leukemias (AL) with KMT2A rearrangements (KMT2Ar, also known as MLL) and mutant nucleophosmin 1 (NPM1m) acute myeloid leukemia (AML). MEN1 is essential for sustaining leukemic transformation due to its interaction with wild-type KMT2A and KMT2A fusion proteins, leading to the dysregulation of KMT2A target genes. MEN1 inhibitors (MIs), such as revumenib, ziftomenib, and other active small molecules, represent a promising new class of therapies currently under clinical development. By disrupting the MEN1-KMT2Ar complex, a group of proteins involved in chromatin remodeling, MIs induce apoptosis and differentiation AL expressing KMT2Ar or NPM1m AML. Phase I and II clinical trials have evaluated MIs as standalone treatments and combined them with other synergistic drugs, yielding promising results. These trials have demonstrated notable response rates with manageable toxicities. Among MIs, ziftomenib received orphan drug and breakthrough therapy designations from the European Medicines Agency in January 2024 and the Food and Drug Administration (FDA) in April 2024, respectively, for treating R/R patients with NPM1m AML. Additionally, in November 2024, the FDA approved revumenib for treating R/R patients with KMT2Ar-AL. This review focuses on the pathophysiology of MI-sensitive AL, primarily AML. It illustrates data from clinical trials and discusses the emergence of resistance mechanisms. In addition, we outline future directions for the use of MIs and emphasize the need for further research to fully realize the potential of these novel compounds, especially in the context of specific genetic subtypes of challenging AL. Full article

Background and Objectives: Revumenib (SNDX-5613) is a powerful and specific inhibitor of the menin–KMT2A binding interaction. It is a small molecule that is currently being researched to treat KMT2A-rearranged (KMT2Ar) acute leukemias. Revumenib (RVB) has received Orphan Drug Designation from the US FDA for treating patients with AML. It has also been granted Fast Track designation by the FDA for treating pediatric and adult patients with R/R acute leukemias that have a KMT2Ar or NPM1 mutation. Materials and Methods: The target of this research was to create a fast, precise, green, and extremely sensitive UPLC-MS/MS technique for the estimation of the RVB level in human liver microsomes (HLMs), employing an ESI source. The validation procedures were carried out in accordance with the bioanalytical technique validation requirements established by the US Food and Drug Administration that involve linearity, selectivity, precision, accuracy, stability, matrix effect, and extraction recovery. The outcome data of the validation features of the UPLC-MS/MS approach were acceptable according to FDA guidelines. RVB parent ions were formed in the positive ESI source and its two fragment ions were estimated employing multiple reaction monitoring (MRM) mode. The separation of RVB and encorafenib was achieved using a C8 column (2.1 mm, 50 mm, and 3.5 µm) and isocratic mobile phase. Results: The RVB calibration curve linearity ranged from 1 to 3000 ng/mL (y = 0.6515x − 0.5459 and R² = 0.9945). The inter-day precision and accuracy spanned from −0.23% to 11.33%, while the intra-day precision and accuracy spanned from −0.88% to 11.67%, verifying the reproducibility of the UPLC-MS/MS analytical technique. The sensitivity of the developed methodology demonstrated its capability to quantify RVB levels at an LOQ of 0.96 ng/mL. The AGREE score was 0.77, confirming the greenness of the current method. The low in vitro t_1/2 (14.93 min) and high intrinsic clearance (54.31 mL/min/kg) of RVB revealed that RVB shares similarities with medications that have a high extraction ratio. Conclusions: The present LC-MS/MS approach is considered the first analytical approach with the application of metabolic stability assessment for RVB estimation in HLMs. These methods are essential for advancing the development of new pharmaceuticals, particularly in enhancing metabolic stability. Full article

Germline mutations in the MEN1 gene encoding menin protein cause multiple endocrine neoplasia type 1 (MEN1) syndrome. Recent evidence suggests that inhibiting the interaction of menin with its crucial oncogenic protein partners represents a promising therapeutic strategy to AML. Menin plays a critical role in lysine methyltransferase 2A (KMT2A)-gene-rearranged and NPM1-m acute leukemias, both associated with adverse outcomes with current standard therapies, especially in the relapsed/refractory setting. Disrupting the menin–KMT2A interaction affects the proleukemogenic HOX/MEIS transcription program. This disruption leads to the differentiation of KMT2Ar and NPM1-m AML cells. Small molecular inhibitors of the menin–KMT2A interaction target the central cavity of MEN1 to inhibit the MEN1-KMT2A interaction and could target a similar transcriptional dependency in other leukemia subsets, broadening their therapeutic potential. These agents, both as monotherapies and in combination with synergistic drugs, are undergoing preclinical and clinical evaluation with promising early results. With the growing literature around menin inhibitors in AML, we discussed the biology of menin, its mechanism of action, its interacting partners in leukemia, possible inhibitors, their implications, synergistic drugs, and future therapeutic strategies in this review. Full article

The protein menin is encoded by the MEN1 gene and primarily serves as a nuclear scaffold protein, regulating gene expression through its interaction with and regulation of chromatin modifiers and transcription factors. While the scope of menin’s functions continues to expand, one area of growing investigation is the role of menin in cancer. Menin is increasingly recognized for its dual function as either a tumor suppressor or a tumor promoter in a highly tumor-dependent and context-specific manner. While menin serves as a suppressor of neuroendocrine tumor growth, as seen in the cancer risk syndrome multiple endocrine neoplasia type 1 (MEN1) syndrome caused by pathogenic germline variants in MEN1, recent data demonstrate that menin also suppresses cholangiocarcinoma, pancreatic ductal adenocarcinoma, gastric adenocarcinoma, lung adenocarcinoma, and melanoma. On the other hand, menin can also serve as a tumor promoter in leukemia, colorectal cancer, ovarian and endometrial cancers, Ewing sarcoma, and gliomas. Moreover, menin can either suppress or promote tumorigenesis in the breast and prostate depending on hormone receptor status and may also have mixed roles in hepatocellular carcinoma. Here, we review the rapidly expanding literature on the role and function of menin across a broad array of different cancer types, outlining tumor-specific differences in menin’s function and mechanism of action, as well as identifying its therapeutic potential and highlighting areas for future investigation. Full article

Over the past few decades, the worldwide incidence of cutaneous melanoma, a malignant neoplasm arising from melanocytes, has been increasing markedly, leading to the highest rate of skin cancer-related deaths. While localized tumors are easily removed by excision surgery, late-stage metastatic melanomas are refractory to treatment and exhibit a poor prognosis. Consequently, unraveling the molecular mechanisms underlying melanoma tumorigenesis and metastasis is crucial for developing novel targeted therapies. We found that the multiple endocrine neoplasia type 1 (MEN1) gene product Menin is required for the transforming growth factor beta (TGFβ) signaling pathway to induce cell growth arrest and apoptosis in vitro and prevent tumorigenesis in vivo in preclinical xenograft models of melanoma. We further identified point mutations in two MEN1 family members affected by melanoma that led to proteasomal degradation of the MEN1 gene product and to a loss of TGFβ signaling. Interestingly, blocking the proteasome degradation pathway using an FDA-approved drug and RNAi targeting could efficiently restore MEN1 expression and TGFβ transcriptional responses. Together, these results provide new potential therapeutic strategies and patient stratification for the treatment of cutaneous melanoma. Full article

Encoded by the MEN1 gene, menin protein is a fusion protein that is essential for the oncogenic transformation of mixed-lineage leukemia (MLL) and leads to acute leukemia (AL). Therefore, accumulating evidence has demonstrated that inhibition of the high-affinity relationship between menin and mixed-lineage leukemia 1 (MLL1 and KMT2A) is an effective treatment for MLL-rearranged (MLL-r) leukemia in vitro and in vivo. Meanwhile, recent studies found that menin–MLL1 interaction inhibitors exhibited a firm tumor suppressive ability in specific cancer cells, such as prostate cancer, breast cancer, liver cancer, and lung cancer. Overall, it seems to serve as a novel therapeutic means for cancers. Herein, we review the recent progress in exploring the inhibitors of small molecule menin–MLL1 interactions. The molecular mechanisms of these inhibitors’ functions and their application prospects in the treatment of AL and cancers are explored. Full article

Acute myeloid leukemia (AML) represents 80% of acute leukemia in adults and is characterized by clonal expansion of hematopoietic stem cells secondary to genomic mutations, rendering a selective growth advantage to the mutant clones. NPM1mut is found in around 30% of AML and clinically presents with leukocytosis, high blast percentage and extramedullary involvement. Considered as a “gate-keeper” mutation, NPM1mut appears to be a “first hit” in the process of leukemogenesis and development of overt leukemia. Commonly associated with other mutations (e.g., FLT 3, DNMT3A, TET2, SF3B1), NPM1 mutation in AML has an important role in diagnosis, prognosis, treatment and post-treatment monitoring. Several novel therapies targeting NPM1 are being developed in various clinical phases with demonstration of efficacy. In this review, we summarize the pathophysiology of the NPM1 gene mutation in AML, clinical implications and the novel targeted therapies to date. Full article

After forty years of essentially unchanged treatment in acute myeloid leukemia (AML), innovation over the past five years has been rapid, with nine drug approvals from 2016 to 2021. Increased understanding of the molecular changes and genetic ontology of disease have led to targeting mutations in isocitrate dehydrogenase, FMS-like tyrosine kinase 3 (FLT3), B-cell lymphoma 2 and hedgehog pathways. Yet outcomes remain variable; especially in defined molecular and genetic subgroups such as NPM1 (Nucleophosmin 1) mutations, 11q23/KMT2A rearranged and TP53 mutations. Emerging therapies seek to address these unmet needs, and all three of these subgroups have promising new therapeutic approaches. Here, we will discuss the normal biological roles of menin in acute leukemia, notably in KMT2A translocations and NPM1 mutation, as well as current drug development. We will also explore how CD47 inhibition may move immunotherapy into front-line settings and unlock new treatment strategies in TP53 mutated disease. We will then consider how these new therapeutic advances may change the management of AML overall. Full article

Multiple endocrine neoplasia type 1 (MEN1) is an inherited disease caused by mutations in the MEN1 gene encoding a nuclear protein menin. Among those different endocrine tumors of MEN1, the pancreatic neuroendocrine tumors (PNETs) are life-threatening and frequently implicated. Since there are uncertainties in genotype and phenotype relationship and there are species differences between humans and mice, it is worth it to replenish the mice model with human cell resources. Here, we tested whether the patient-origin induced pluripotent stem cell (iPSC) lines could phenocopy some defects of MEN1. In vitro β-cell differentiation revealed that the percentage of insulin-positive cells and insulin secretion were increased by at least two-fold in MEN1-iPSC derived cells, which was mainly resulted from significantly higher proliferative activities in the pancreatic progenitor stage (Day 7–13). This scenario was paralleled with increased expressions of prohormone convertase1/3 (PC1/3), glucagon-like peptide-1 (GLP-1), GLP-1R, and factors in the phosphatidylinositol 3-kinase (PI3K)/AKT signal pathway, and the GLP-1R was mainly expressed in β-like cells. Blockages of either GLP-1R or PI3K significantly reduced the percentages of insulin-positive cells and hypersecretion of insulin in MEN1-derived cells. Furthermore, in transplantation of different stages of MEN1-derived cells into immune-deficient mice, only those β-like cells produced tumors that mimicked the features of the PNETs from the original patient. To the best of our knowledge, this was the first case using patient-origin iPSCs modeling most phenotypes of MEN1, and the results suggested that GLP-1R may be a potential therapeutic target for MEN1-related hyperinsulinemia. Full article

Human menin is a nuclear protein that participates in many cellular processes, as transcriptional regulation, DNA damage repair, cell signaling, cell division, proliferation, and migration, by interacting with many other proteins. Mutations of the gene encoding menin cause multiple endocrine neoplasia type 1 (MEN1), a rare autosomal dominant disorder associated with tumors of the endocrine glands. In order to characterize the structural and functional effects at protein level of the hundreds of missense variations, we investigated by computational methods the wild-type menin and more than 200 variants, predicting the amino acid variations that change secondary structure, solvent accessibility, salt-bridge and H-bond interactions, protein thermostability, and altering the capability to bind known protein interactors. The structural analyses are freely accessible online by means of a web interface that integrates also a 3D visualization of the structure of the wild-type and variant proteins. The results of the study offer insight into the effects of the amino acid variations in view of a more complete understanding of their pathological role. Full article

Multiple endocrine neoplasia type 1 (MEN1) is a rare autosomal dominant inherited multiple cancer syndrome of neuroendocrine tissues. Tumors are caused by an inherited germinal heterozygote inactivating mutation of the MEN1 tumor suppressor gene, followed by a somatic loss of heterozygosity (LOH) of the MEN1 gene in target neuroendocrine cells, mainly at parathyroids, pancreas islets, and anterior pituitary. Over 1500 different germline and somatic mutations of the MEN1 gene have been identified, but the syndrome is completely missing a direct genotype-phenotype correlation, thus supporting the hypothesis that exogenous and endogenous factors, other than MEN1 specific mutation, are involved in MEN1 tumorigenesis and definition of individual clinical phenotype. Epigenetic factors, such as microRNAs (miRNAs), are strongly suspected to have a role in MEN1 tumor initiation and development. Recently, a direct autoregulatory network between miR-24, MEN1 mRNA, and menin was demonstrated in parathyroids and endocrine pancreas, showing a miR-24-induced silencing of menin expression that could have a key role in initiation of tumors in MEN1-target neuroendocrine cells. Here, we review the current knowledge on the post-transcriptional regulation of MEN1 and menin expression by miR-24, and its possible direct role in MEN1 syndrome, describing the possibility and the potential approaches to target and silence this miRNA, to permit the correct expression of the wild type menin, and thereby prevent the development of cancers in the target tissues. Full article