A clinicopathological study of non-functioning pituitary neuroendocrine tumours using the World Health Organization 2022 classification.

Background: The 2022 World Health Organization (WHO) classification of pituitary neuroendocrine tumour (PitNET) supersedes the previous one in 2017 and further consolidates the role of transcription factors (TF) in the diagnosis of PitNET. Here, we investigated the clinical utility of the 2022 WHO classification, as compared to that of 2017, in a cohort of patients with non-functioning PitNET (NF-PitNET). Methods: A total of 113 NF-PitNET patients who underwent resection between 2010 and 2021, and had follow-up at Queen Mary Hospital, Hong Kong, were recruited. Surgical specimens were re-stained for the three TF: steroidogenic factor (SF-1), T-box family member TBX19 (TPIT) and POU class 1 homeobox 1 (Pit-1). The associations of different NF-PitNET subtypes with tumour-related outcomes were evaluated by logistic and Cox regression analyses. Results: Based on the 2022 WHO classification, the majority of NF-PitNET was SF-1-lineage tumours (58.4%), followed by TPIT-lineage tumours (18.6%), tumours with no distinct lineage (16.8%) and Pit-1-lineage tumours (6.2%). Despite fewer entities than the 2017 classification, significant differences in disease-free survival were present amongst these four subtypes (Log-rank test p=0.003), specifically between SF-1-lineage PitNET and PitNET without distinct lineage (Log-rank test p<0.001). In multivariable Cox regression analysis, the subtype of PitNET without distinct lineage (HR 3.02, 95% CI 1.28-7.16, p=0.012), together with tumour volume (HR 1.04, 95% CI 1.01-1.07, p=0.017), were independent predictors of a composite of residual or recurrent disease. Conclusion: The 2022 WHO classification of PitNET is a clinically useful TF and lineage-based system for subtyping NF-PitNET with different tumour behaviour and prognosis.

Pegvisomant and pasireotide in PRL and GH co-secreting vs GH-secreting Pit-NETs.

The objective of the study was to evaluate the efficacy of second-line therapies in patients with acromegaly caused by a growth hormone (GH) and prolactin (PRL) co-secreting pituitary neuroendocrine tumor (GH&PRL-Pit-NET) compared to their efficacy in patients with acromegaly caused by a GH-secreting pituitary neuroendocrine tumor (GH-Pit-NET). This is a multicenter retrospective study of patients with acromegaly on treatment with pasireotide and/or pegvisomant. Patients were classified in two groups: GH&PRL-Pit-NETs when evidence of hyperprolactinemia and immunohistochemistry (IHC) for GH and PRL was positive or if PRL were >200 ng/dL regardless of the PRL-IHC and GH-Pit-NETs when the previously mentioned criteria were not met. A total of 28 cases with GH&PRL-Pit-NETs and 122 with GH-Pit-NETs met the inclusion criteria. GH&PRL-Pit-NETs presented at a younger age, caused hypopituitarism, and were invasive more frequently than GH-Pit-NETs. There were 124 patients treated with pegvisomant and 49 with pasireotide at any time. The efficacy of pegvisomant for IGF-1 normalization was of 81.5% and of pasireotide of 71.4%. No differences in IGF-1 control with pasireotide and with pegvisomant were observed between GH&PRL-Pit-NETs and GH-Pit-NETs. All GH&PRL-Pit-NET cases treated with pasireotide (n = 6) and 82.6% (n = 19/23) of the cases treated with pegvisomant normalized PRL levels. No differences in the rate of IGF-1 control between pegvisomant and pasireotide were detected in patients with GH&PRL-Pit-NETs (84.9% vs 66.7%, P = 0.178). We conclude that despite the more aggressive behavior of GH&PRL-Pit-NETs than GH-Pit-NETs, no differences in the rate of IGF-1 control with pegvisomant and pasireotide were observed between both groups, and both drugs have shown to be effective treatments to control IGF-1 and PRL hypersecretion in these tumors.

Three-dimensional chromatin landscapes in somatotroph tumour.

BACKGROUND: The three-dimensional (3D) genome architecture plays a critical role inregulating gene expression. However, the specific alterations in thisarchitecture within somatotroph tumors and their implications for gene expression remain largely unexplored. METHODS: We employed Hi-C and RNA-seq analyses to compare the 3D genomic structures of somatotroph tumors with normal pituitary tissue. This comprehensive approachenabled the characterization of A/B compartments, topologically associateddomains (TADs), and chromatin loops, integrating these with gene expression patterns. RESULTS: We observed a decrease in both the frequency of chromosomal interactions andthe size of TADs in tumor tissue compared to normal tissue. Conversely, the number of TADs and chromatin loops was found to be increased in tumors. Integrated analysis of Hi-C and RNA-seq data demonstrated that changes inhigher-order chromat in structure were associated with alterations in gene expression. Specifically, genes in A compartments showed higher density and increased expression relative to those in B compartments. Moreover, the weakand enhanced insulation boundaries were identified, and the associated genes were enriched in the Wnt/ß-Catenin signaling pathway. We identified the gainedand lost loops in tumor and integrated these differences with transcriptional changes to examine the functional relevance of the identified loops. Notably, we observed an enhanced insulation boundary and a greater number of loops in the TCF7L2 gene region within tumors, which was accompanied by an upregulation of TCF7L2 expression. Subsequently, TCF7L2 expression was confirmed through qRT-PCR, and upregulated TCF7L2 prompted cell proliferation and growth hormone (GH) secretion in vitro. CONCLUSION: Our results provide comprehensive 3D chromatin architecture maps of somatotroph tumors and offer a valuable resource for furthering the understanding of the underlying biology and mechanisms of gene expression regulation.

Demethylation of TIMP2 and TIMP3 Inhibits Cell Proliferation, Migration, and Invasion in Pituitary Adenomas.

OBJECTIVE: Tissue inhibitors of matrix metalloproteinases (TIMPs) are prognostic markers in cancers. However, the role of TIMPs in DNA methylation during invasive pituitary adenoma (PA) remains unclear. The purpose of this study was to assess the effects of TIMP2 and TIMP3 promoter demethylation on the proliferation, migration, and invasion of invasive PA cells. METHODS: Methylation-specific polymerase chain reaction (PCR), quantitative PCR, and western blots were used to analyze the promoter methylation and expression of TIMP1-3. Cell counting kit-8 (CCK-8), wound healing, and transwell assays were carried out to determine the effects of TIMP2 and TIMP3 demethylation. RESULTS: TIMP1-3 showed downregulated expression in invasive PA tissues and cell lines (p < 0.05). The low expression of TIMP1-3 was due to promoter methylation of these genes (p < 0.05). The results showed that downregulation of TIMP2 and TIMP3 can promote cell proliferation, migration, and invasion (p < 0.05), whereas overexpression of TIMP2 and TIMP3 can inhibit cell proliferation, migration, and invasion (p < 0.05). After treatment with 5-azacytidine (5-AzaC), the cell activity decreased, the proliferation rate decreased, and the invasion ability weakened (p < 0.05). Treatment with 5-AzaC increased TIMP2 and TIMP3 expression and decreased DNA (cytosine-5-)-methyltransferase 1 (DNMT1), DNMT3a, and DNMT3b expression (p < 0.05). CONCLUSIONS: We showed that DNA methylation causes the silencing of TIMP2 and TIMP3 in invasive PA, it can also lead to malignant cell proliferation and cause pathological changes, whereas the use of 5-AzaC can inhibit the methylation process and can inhibit cell proliferation. Our results provide a novel method for clinical diagnosis and prevention of invasive PA.

Expression analysis of necroptosis related genes and lncRNAs in patients with pituitary neuroendocrine tumors.

Necroptosis can either be the cause of tumorigenesis or it can impede its process. Recently, it has been proved that long non-coding RNAs (lncRNAs) have different crucial roles at cellular level, especially on cell death. Regarding the important role of necroptosis and lncRNAs in the pathogenesis of different cancers, especially pituitary adenomas (PAs), we assessed expression levels of two necroptosis related genes, namely TRADD and BIRC2, in addition to three related lncRNAs, namely FLVCR1-DT, MAGI2-AS3, and NEAT1 in PAs compared with adjacent normal tissues (ANTs). TRADD had no significant difference between two groups; however, BIRC2, FLVCR1-DT, MAGI2-AS3, and NEAT1 were upregulated in PAs compared to ANTs (Expression ratios [95% CI] = 2.3 [1.47-3.6], 2.13 [1.02-4.44], 3.01 [1.76-5.16] and 2.47 [1.37-4.45], respectively). When taking into account different types of PAs, significant upregulation of BIRC2, MAGI2-AS3 and NEAT1 was recorded in non-functioning PAs compared with corresponding ANTs (Expression ratios [95% CI] =1.9 [1.04-3.43], 2.69 [1.26-5.72] and 2.22 [0.98-5.01], respectively). Additionally, higher levels of BIRC2 were associated with higher flow of CSF (P value=0.048). Moreover, higher Knosp classified tumors had lower levels of BIRC2 (P value=0.001). Finally, lower levels of MAGI2-AS3 were associated with larger tumor size (P value=0.006). NEAT1 expression was correlated with FLVCR1-DT and TRADD. TRADD expression was correlated with FLVCR1-DT. Additional correlation was observed between expression of BIRC2 and MAGI2-AS3. In sum, this study provides evidence that dysregulated levels of studied genes could contribute to the pathogenesis of pituitary tumors.

TNF-α can promote membrane invasion by activating the MAPK/MMP9 signaling pathway through autocrine in bone-invasive pituitary adenoma.

AIMS: A bone-invasive pituitary adenoma exhibits aggressive behavior, leading to a worse prognosis. We have found that TNF-α promotes bone invasion by facilitating the differentiation of osteoclasts, however, before bone-invasive pituitary adenoma invades bone tissue, it needs to penetrate the dura mater, and this mechanism is not yet clear. METHODS: We performed transcriptome microarrays on specimens of bone-invasive pituitary adenomas (BIPAs) and noninvasive pituitary adenomas (NIPAs) and conducted differential expressed gene analysis and enrichment analysis. We altered the expression of TNF-α through plasmids, then validated the effects of TNF-α on GH3 cells and verified the efficacy of the TNF-α inhibitor SPD304. Finally, the effects of TNF-α were validated in in vivo experiments. RESULTS: Pathway act work showed that the MAPK pathway was significantly implicated in the pathway network. The expression of TNF-α, MMP9, and p-p38 is higher in BIPAs than in NIPAs. Overexpression of TNF-α elevated the expression of MAPK pathway proteins and MMP9 in GH3 cells, as well as promoted proliferation, migration, and invasion of GH3 cells. Flow cytometry indicated that TNF-α overexpression increased the G2 phase ratio in GH3 cells and inhibited apoptosis. The expression of MMP9 was reduced after blocking the P38 MAPK pathway; overexpression of MMP9 promoted invasion of GH3 cells. In vivo experiments confirm that the TNF-α overexpression group has larger tumor volumes. SPD304 was able to suppress the effects caused by TNF-α overexpression. CONCLUSION: Bone-invasive pituitary adenoma secretes higher levels of TNF-α, which then acts on itself in an autocrine manner, activating the MAPK pathway and promoting the expression of MMP9, thereby accelerating the membrane invasion process. SPD304 significantly inhibits the effect of TNF-α and may be applied in the clinical treatment of bone-invasive pituitary adenoma.

Curcumin affects autophagy of prolactinoma cells by upregulating miR-206 to exert antitumor effects.

We explored the effects of curcumin on the aberrant biological behaviors of prolactinoma cells and the downstream pathways through which curcumin exerts its antitumor effects. We used quantitative reverse transcription-polymerase chain reaction assays to measure miR-206 expression levels in peripheral blood samples from patients with prolactinoma before and after curcumin treatment. We also investigated the proliferation level, viability, and invasion ability of groups of cells treated with different concentrations of curcumin using 3-(4,5)-dimethylthiahiazo (-z-y1)-3-di-phenytetrazoliumromide (MTT) assays, cell cloning assays, and Transwell assays, respectively. Furthermore, we determined the levels of autophagy-related proteins and protein kinase B/mammalian target of the rapamycin (Akt/mTOR) signaling pathway-related proteins in each group of treated cells by western blot. Curcumin treatment upregulated miR-206 expression levels in the peripheral blood of patients with prolactinoma and in GH3 cells. Knockdown of miR-206 expression enhanced the proliferation and invasive ability of GH3 cells, while curcumin treatment effectively inhibited the aberrant biological behavior of GH3 cells enhanced by miR-206 knockdown. miR-206 knockdown also activated the Akt/mTOR signaling pathway and inhibited autophagy in GH3 cells, and these changes were effectively reversed by curcumin treatment. Thus, curcumin inhibited the Akt/mTOR signaling pathway and promoted cell autophagy by miR-206 upregulation, resulting in antitumor effects that inhibited prolactinoma cell proliferation and invasion.

Metabolic and inflammatory parameters in relation to baseline characterization and treatment outcome in patients with prolactinoma: insights from a retrospective cohort study at a single tertiary center.

Background: Prolactinomas (PRLs) are prevalent pituitary adenomas associated with metabolic changes and increased cardiovascular morbidity. This study examined clinical, endocrine, metabolic, and inflammatory profiles in PRL patients, aiming to identify potential prognostic markers. Methods: The study comprised data from 59 PRL patients gathered in a registry at the University Hospital of Zurich. Diagnostic criteria included MRI findings and elevated serum prolactin levels. We assessed baseline and follow-up clinical demographics, metabolic markers, serum inflammation-based scores, and endocrine parameters. Treatment outcomes were evaluated based on prolactin normalization, tumor shrinkage, and cabergoline dosage. Results: The PRL cohort exhibited a higher prevalence of overweight/obesity, prediabetes/diabetes mellitus, and dyslipidemia compared to the general population. Significant correlations were found between PRL characteristics and BMI, HbA1c, and fT4 levels. Follow-up data indicated decreases in tumor size, tumor volume, prolactin levels, and LDL-cholesterol, alongside increases in fT4 and sex hormones levels. No significant associations were observed between baseline parameters and tumor shrinkage at follow-up. A positive association was noted between PRL size/volume and the time to achieve prolactin normalization, and a negative association with baseline fT4 levels. Conclusion: This study underscores the metabolic significance of PRL, with notable correlations between PRL parameters and metabolic indices. However, inflammatory markers were not significantly correlated with patient stratification or outcome prediction. These findings highlight the necessity for standardized follow-up protocols and further research into the metabolic pathogenesis in PRL patients.

Single-cell transcriptomics reveal distinct immune-infiltrating phenotypes and macrophage-tumor interaction axes among different lineages of pituitary neuroendocrine tumors.

BACKGROUND: Pituitary neuroendocrine tumors (PitNETs) are common gland neoplasms demonstrating distinctive transcription factors. Although the role of immune cells in PitNETs has been widely recognized, the precise immunological environment and its control over tumor cells are poorly understood. METHODS: The heterogeneity, spatial distribution, and clinical significance of macrophages in PitNETs were analyzed using single-cell RNA sequencing (scRNA-seq), bulk RNA-seq, spatial transcriptomics, immunohistochemistry, and multiplexed quantitative immunofluorescence (QIF). Cell viability, cell apoptosis assays, and in vivo subcutaneous xenograft experiments have confirmed that INHBA-ACVR1B influences the process of tumor cell apoptosis. RESULTS: The present study evaluated scRNA-seq data from 23 PitNET samples categorized into 3 primary lineages. The objective was to explore the diversity of tumors and the composition of immune cells across these lineages. Analyzed data from scRNA-seq and 365 bulk RNA sequencing samples conducted in-house revealed the presence of three unique subtypes of tumor immune microenvironment (TIME) in PitNETs. These subtypes were characterized by varying levels of immune infiltration, ranging from low to intermediate to high. In addition, the NR5A1 lineage is primarily associated with the subtype characterized by limited infiltration of immune cells. Tumor-associated macrophages (TAMs) expressing CX3CR1+, C1Q+, and GPNMB+ showed enhanced contact with tumor cells expressing NR5A1 + , TBX19+, and POU1F1+, respectively. This emphasizes the distinct interaction axes between TAMs and tumor cells based on their lineage. Moreover, the connection between CX3CR1+ macrophages and tumor cells via INHBA-ACVR1B regulates tumor cell apoptosis. CONCLUSIONS: In summary, the different subtypes of TIME and the interaction between TAM and tumor cells offer valuable insights into the control of TIME that affects the development of PitNET. These findings can be utilized as prospective targets for therapeutic interventions.

[Acidophil stem cell pituitary neuroendocrine tumors/adenoma: a clinicopathological analysis of five cases].

Objective: To investigate the clinicopathological characteristics of acidophil stem cell pituitary neuroendocrine tumors (PitNET)/adenoma. Methods: Five cases of acidophil stem cell PitNET/adenoma were diagnosed between May 2022 and July 2023 at the Second Hospital of Hebei Medical University, Shijiazhuang, China. The clinicopathological features of the tumor were analyzed by using histology, immunohistochemistry, and electron microscopy. The relevant literature was reviewed. Results: There were 1 male and 4 females, aged from 23 to 69 years. Patient 3 was 55 years old at the time of diagnosis and first surgery, and relapsed 5 years later. The patients' median age was 32 years. Patients 1 and 5 showed elevated blood prolactin, with various degrees of hormonal symptoms except Patient 3, who showed only tumor compression symptoms. Imaging studies showed that all cases involved the sellar floor. The tumors of Patients 1, 2 and 5 were closely related to the cavernous sinus segment of the internal carotid artery. The tumors exhibited a diffuse growth pattern with chromophobic to slightly acidophilic cytoplasm. A few of tumor cells showed chromophobic cytoplasm. The nucleoli were conspicuous. Intranuclear inclusion bodies and variably-sized clear vacuoles were observed occasionally. Under electron microscope, marked mitochondrial abnormalities were observed, including increased mitochondria number, expanded hypertrophy, and absence of mitochondrial ridge fracture. Some mitochondrial matrices were dense, while some were vacuolated. Conclusions: Acidophil stem cell PitNET/adenoma is a rare type of pituitary adenomas/PitNETs. It often has a more clinically aggressive manner with immature cells, diffuse expression of PIT1, prolactin, and varying degrees of growth hormone expression. Because of the obvious diversity of their clinical hormone status and hormone immune expression, the diagnosis of this type tumor is still a challenge.

Identification of core genes of craniopharyngioma angiogenesis based on single-cell nuclear transcriptome sequencing.

This study aimed to explore the core genes of craniopharyngioma angiogenesis for targeted vascular therapy based on single-cell nuclear transcriptome sequencing. For single-cell nuclear transcriptome sequencing, we collected six samples from the tumor center and adjacent hypothalamic tumor tissues from three patients with craniopharyngioma, as well as four normal brain tissues based on Gene Expression Omnibus. We screened genes with differential up-regulation between vascular endothelial cells of craniopharyngioma and those of normal brain tissues, performed GO and KEGG analysis, constructed the protein-protein interaction network, and selected key genes verified using immunofluorescence. After data cleaning and quality control, 623 craniopharyngioma endothelial cells and 439 healthy brain endothelial cells were obtained. Compared with normal brain endothelial cells, craniopharyngioma endothelial cells were screened for 394 differentially up-expressed genes (DEGs). GO and KEGG results showed that DEGs probably modulated endothelial cells, adherens junction, focal adhesion, migration, actin cytoskeleton, and invasion via the PI3K-AKT, Rap1, Ras, Wnt, and Hippo pathways. The core genes screened were CTNNB1, PTK2, ITGB1, STAT3, FYN, HIF1A, VCL, SMAD3, PECAM1, FOS, and CDH5. This study obtained possible anti-angiogenic genes in craniopharyngioma. Our results shed novel insights into molecular mechanisms and craniopharyngioma treatment.

The molecular biology of sporadic acromegaly.

GH-secreting tumors represent 15 % to 20 % of all pituitary neuroendocrine tumors (pitNETs), of which 95 % occur in a sporadic context, without an identifiable inherited cause. Recent multi-omic approaches have characterized the epigenomic, genomic, transcriptomic, proteomic and kynomic landscape of pituitary tumors. Transcriptomic analysis has allowed us to discover specific transcription factors driving the differentiation of pituitary tumors and gene expression patterns. GH-secreting, along with PRL- and TSH-secreting pitNETs are driven by POU1F1; ACTH-secreting tumors are determined by TBX19; and non-functioning tumors, which are predominantly of gonadotrope differentiation are conditioned by NR5A1. Upregulation of certain miRNAs, such as miR-107, is associated with tumor progression, while downregulation of others, like miR-15a and miR-16-1, correlates with tumor size reduction. Additionally, miRNA expression profiles are linked to treatment resistance and clinical outcomes, providing insights into potential therapeutic targets. Specific somatic mutations in GNAS, PTTG1, GIPR, HGMA2, MAST and somatic variants associated with cAMP, calcium signaling, and ATP pathways have also been associated with the development of acromegaly. This review focuses on the oncogenic mechanisms by which sporadic acromegaly can develop, covering a complex series of molecular alterations that ultimately alter the balance between proliferation and apoptosis, and dysregulated hormonal secretion.

Axl as a potential therapeutic target for adamantinomatous craniopharyngiomas: Based on single nucleus RNA-seq and spatial transcriptome profiling.

Craniopharyngiomas (CPs), particularly Adamantinomatous Craniopharyngiomas (ACPs), often exhibit a heightened risk of postoperative recurrence and severe complications of the endocrine and hypothalamic function. The primary objective of this study is to investigate potential novel targeted therapies within the microenvironment of ACP tumors. Cancer-Associated Fibroblasts (CAFs) were identified in the craniopharyngioma microenvironment, notably in regions characterized by cholesterol clefts, wet keratin, ghost cells, and fibrous stroma in ACPs. CAFs, alongside ghost cells, basaloid-like epithelium cells and calcifications, were found to secrete PROS1 and GAS6, which can activate AXL receptors on the surface of tumor epithelium cells, promoting immune suppression and tumor progression in ACPs. Additionally, the AXL inhibitor Bemcentinib effectively inhibited the proliferation organoids and enhanced the immunotherapeutic efficacy of Atezolizumab. Furthermore, neural crest-like cells were observed in the glial reactive tissue surrounding finger-like protrusions. Overall, our results revealed that the AXL might be a potentially effective therapeutic target for ACPs.

Histopathology of growth hormone-secreting pituitary tumors: State of the art and new perspectives.

Somatotroph (GH) adenomas/PitNETs typically arise from adenohypophysis and are biochemically active, leading to acromegaly and gigantism. More rarely, they present with ectopic origin and do not present overt biochemical or clinical features (silent variants). Histopathological examination should consider the clinical and radiological background, and include multiple steps assessing tumor morphology, pituitary transcription factors (PTFs), hormone secretion, proliferation markers, granulation, and somatostatin receptors (STRs), aimed at depicting as better as possible tumor origin (in case of non-functioning and/or metastatic tumor), and clinical behavior, including response to treatment. GH-secreting tumors are part of the Pit-1 family tumors and can secrete GH only (pure somatotrophs) or co-secrete prolactin (mixed tumors; in this case, various histological subtypes have been identified). Each subtype presents unique radiological, biochemical, and clinical characteristic. Therefore, the integration of biochemical, clinical, radiological, and histopathological elements is fundamental for proper diagnosis and management of pituitary adenomas/PitNETs, to be performed in referral Centers. In more recent times, the importance of genetic and epigenetic evaluation in the characterization of pituitary tumors (i.e., early identification of aggressive variants) has been outlined by some large studies, with the intention of improving targeted treatments.

Gut microbiota composition and metabolic characteristics in patients with Craniopharyngioma.

BACKGROUND: Emerging evidence suggests that the gut microbiota is associated with various intracranial neoplastic diseases. It has been observed that alterations in the gut microbiota are present in gliomas, meningiomas, and pituitary neuroendocrine tumors (Pit-NETs). However, the correlation between gut microbiota and craniopharyngioma (CP), a rare embryonic malformation tumor in the sellar region, has not been previously mentioned. Consequently, this study aimed to investigate the gut microbiota composition and metabolic patterns in CP patients, with the goal of identifying potential therapeutic approaches. METHODS: We enrolled 15 medication-free and non-operated patients with CP and 15 healthy controls (HCs), conducting sequential metagenomic and metabolomic analyses on fecal samples to investigate changes in the gut microbiota of CP patients. RESULTS: The composition of gut microbiota in patients with CP compared to HCs show significant discrepancies at both the genus and species levels. The CP group exhibits greater species diversity. And the metabolic patterns between the two groups vary markedly. CONCLUSIONS: The gut microbiota composition and metabolic patterns in patients with CP differ significantly from the healthy population, presenting potential new therapeutic opportunities.

miR-200b-3p accelerates progression of pituitary adenomas by negatively regulating expression of RECK.

MicroRNA (miR)-200b-3p has been associated with many tumors, but its involvement in pituitary adenoma is unclear. This study investigated the molecular mechanism underlying miR-200b-3p regulation in pituitary adenomas to provide a theoretical basis for treatment. Bioinformatics was used to analyze pituitary adenoma-related genes and screen new targets related to RECK and miRNA. As well, the relationship between miR-200b-3p and RECK protein was verified using a double-luciferase reporter gene assay. The expression of miR-200b-3p in clinical samples was analyzed by in situ hybridization. Transfection of the miR-200b-3p inhibitor and small interfering-RECK (si-RECK) was verified by qPCR. GH3 cell viability and proliferation were detected using CCK8 and EdU assays. Apoptosis was detected by flow cytometry and western blotting. Wound healing and Transwell assays were used to detect cell migration and invasion. The effects of miR-200b-3p and RECK on GH3 cells were verified using salvage experiments. miR-200b-3p was highly expressed in pituitary tumor tissue. Inhibitors of miR-200b-3p inhibited cell proliferation promoted cell apoptosis, inhibited invasion and migration, and inhibited the expression of matrix metalloproteinases. Interestingly, miR-200b-3p negatively regulated RECK. The expression of RECK in pituitary adenoma tissues was lower than that in neighboring tissues. Si-RECK rescued the function of miR-200b-3p inhibitors in the above cellular behaviors, and miR-200b-3p accelerated the development of pituitary adenoma by negatively regulating RECK expression. In summary, this study investigated the molecular mechanism by which miR-200b-3p regulates the progression of pituitary adenoma through the negative regulation of RECK. The findings provide a new target for the treatment of pituitary adenoma.

Lysine Methyltransferase 5A Promotes the Progression of Growth Hormone Pituitary Neuroendocrine Tumors through the Wnt/ß-Catenin Signaling Pathway.

INTRODUCTION: Growth hormone (GH) secreting pituitary adenoma is considered one of the most harmful types of Pituitary Neuroendocrine Tumors (PitNETs). Our previous research has found that high expression of Lysine methyltransferase 5A (KMT5A) is closely related to the proliferation of PitNETs. The aim of this study was to investigate the role and molecular mechanism of KMT5A in the progression of GH PitNETs. METHODS: Immunohistochemistry, qRT-PCR, and Western blot (WB) were used to assess the expression levels of KMT5A in human normal pituitary and GH PitNETs, as well as in rat normal pituitary and GH3 cells. Additionally, we utilized RNA interference technology and treatment with a selective KMT5A inhibitor to decrease the expression of KMT5A in GH3 cells. CCK-8, EdU, flow cytometry (FCM), clone formation, and WB assay were further employed to evaluate the impact of KMT5A on the proliferation of GH3 cells in vitro. A xenograft model was established to evaluate the role of KMT5A in GH PitNETs progression in vivo. RESULTS: KMT5A was highly expressed in GH PitNETs and GH3 cells. Moreover, the reduction of KMT5A expression led to inhibited growth of GH PitNETs and increased apoptosis of tumor cells, as indicated by the findings from CCK-8, EdU, clone formation, and FCM assays. Additionally, WB analysis identified the Wnt/ß-catenin signaling pathway as a potential mechanism through which KMT5A promotes GH PitNETs progression. CONCLUSION: Our research suggests that KMT5A may facilitate the progression of GH PitNETs via the Wnt/ß-catenin signaling pathway. Therefore, KMT5A may serve as a potential therapeutic target and molecular biomarker for GH PitNETs.

Acquired hypothalamic obesity: A clinical overview and update.

Hypothalamic obesity (HO) is a rare and complex disorder that confers substantial morbidity and excess mortality. HO is a unique subtype of obesity characterized by impairment in the key brain pathways that regulate energy intake and expenditure, autonomic nervous system function, and peripheral hormonal signalling. HO often occurs in the context of hypothalamic syndrome, a constellation of symptoms that follow from disruption of hypothalamic functions, for example, temperature regulation, sleep-wake circadian control, and energy balance. Genetic forms of HO, including the monogenic obesity syndromes, often impact central leptin-melanocortin pathways. Acquired forms of HO occur as a result of tumours impacting the hypothalamus, such as craniopharyngioma, surgery or radiation to treat those tumours, or other forms of hypothalamic damage, such as brain injury impacting the region. Risk for severe obesity following hypothalamic injury is increased with larger extent of hypothalamic damage or lesions that contain the medial and posterior hypothalamic nuclei that support melanocortin signalling pathways. Structural damage in these hypothalamic nuclei often leads to hyperphagia, central insulin and leptin resistance, decreased sympathetic activity, low energy expenditure, and increased energy storage in adipose tissue, the collective effect of which is rapid weight gain. Individuals with hyperphagia are perpetually hungry. They do not experience fullness at the end of a meal, nor do they feel satiated after meals, leading them to consume larger and more frequent meals. To date, most efforts to treat HO have been disappointing and met with limited, if any, long-term success. However, new treatments based on the distinct pathophysiology of disturbed energy homeostasis in acquired HO may hold promise for the future.

Primary Cilia as a Tumor Marker in Pituitary Neuroendocrine Tumors.

Pituitary neuroendocrine tumors (PitNETs) account for approximately 15% of all intracranial neoplasms. Although they usually appear to be benign, some tumors display worse behavior, displaying rapid growth, invasion, refractoriness to treatment, and recurrence. Increasing evidence supports the role of primary cilia (PC) in regulating cancer development. Here, we showed that PC are significantly increased in PitNETs and are associated with increased tumor invasion and recurrence. Serial electron micrographs of PITNETs demonstrated different ciliation phenotypes (dot-like versus normal-like cilia) that represented PC at different stages of ciliogenesis. Molecular findings demonstrated that 123 ciliary-associated genes (eg, doublecortin domain containing protein 2, Sintaxin-3, and centriolar coiled-coil protein 110) were dysregulated in PitNETs, representing the upregulation of markers at different stages of intracellular ciliogenesis. Our results demonstrate, for the first time, that ciliogenesis is increased in PitNETs, suggesting that this process might be used as a potential target for therapy in the future.