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1,006 result(s) for "craniopharyngioma"
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Molecular Analyses Reveal Inflammatory Mediators in the Solid Component and Cyst Fluid of Human Adamantinomatous Craniopharyngioma
Abstract Pediatric adamantinomatous craniopharyngioma (ACP) is a highly solid and cystic tumor, often causing substantial damage to critical neuroendocrine structures such as the hypothalamus, pituitary gland, and optic apparatus. Paracrine signaling mechanisms driving tumor behavior have been hypothesized, with IL-6R overexpression identified as a potential therapeutic target. To identify potential novel therapies, we characterized inflammatory and immunomodulatory factors in ACP cyst fluid and solid tumor components. Cytometric bead analysis revealed a highly pro-inflammatory cytokine pattern in fluid from ACP compared to fluids from another cystic pediatric brain tumor, pilocytic astrocytoma. Cytokines and chemokines with particularly elevated concentrations in ACPs were IL-6, CXCL1 (GRO), CXCL8 (IL-8) and the immunosuppressive cytokine IL-10. These data were concordant with solid tumor compartment transcriptomic data from a larger cohort of ACPs, other pediatric brain tumors and normal brain. The majority of receptors for these cytokines and chemokines were also over-expressed in ACPs. In addition to IL-10, the established immunosuppressive factor IDO-1 was overexpressed by ACPs at the mRNA and protein levels. These data indicate that ACP cyst fluids and solid tumor components are characterized by an inflammatory cytokine and chemokine expression pattern. Further study regarding selective cytokine blockade may inform novel therapeutic interventions.
Increased Wingless (Wnt) signaling in pituitary progenitor/stem cells gives rise to pituitary tumors in mice and humans
Wingless (Wnt)/β-catenin signaling plays an essential role during normal development, is a critical regulator of stem cells, and has been associated with cancer in many tissues. Here we demonstrate that genetic expression of a degradation-resistant mutant form of β-catenin in early Rathke's pouch (RP) progenitors leads to pituitary hyperplasia and severe disruption of the pituitary-specific transcription factor 1-lineage differentiation resulting in extreme growth retardation and hypopituitarism. Mutant mice mostly die perinatally, but those that survive weaning develop lethal pituitary tumors, which closely resemble human adamantinomatous craniopharyngioma, an epithelial tumor associated with mutations in the human β-catenin gene. The tumorigenic effect of mutant β-catenin is observed only when expressed in undifferentiated RP progenitors, but tumors do not form when committed or differentiated cells are targeted to express this protein. Analysis of affected pituitaries indicates that expression of mutant β-catenin leads to a significant increase in the total numbers of pituitary progenitor/stem cells as well as in their proliferation potential. Our findings provide insights into the role of the Wnt pathway in normal pituitary development and demonstrate a causative role for mutated β-catenin in an undifferentiated RP progenitor in the genesis of murine and human craniopharyngioma.
Tumour compartment transcriptomics demonstrates the activation of inflammatory and odontogenic programmes in human adamantinomatous craniopharyngioma and identifies the MAPK/ERK pathway as a novel therapeutic target
Adamantinomatous craniopharyngiomas (ACPs) are clinically challenging tumours, the majority of which have activating mutations in CTNNB1. They are histologically complex, showing cystic and solid components, the latter comprised of different morphological cell types (e.g. β-catenin-accumulating cluster cells and palisading epithelium), surrounded by a florid glial reaction with immune cells. Here, we have carried out RNA sequencing on 18 ACP samples and integrated these data with an existing ACP transcriptomic dataset. No studies so far have examined the patterns of gene expression within the different cellular compartments of the tumour. To achieve this goal, we have combined laser capture microdissection with computational analyses to reveal groups of genes that are associated with either epithelial tumour cells (clusters and palisading epithelium), glial tissue or immune infiltrate. We use these human ACP molecular signatures and RNA-Seq data from two ACP mouse models to reveal that cell clusters are molecularly analogous to the enamel knot, a critical signalling centre controlling normal tooth morphogenesis. Supporting this finding, we show that human cluster cells express high levels of several members of the FGF, TGFB and BMP families of secreted factors, which signal to neighbouring cells as evidenced by immunostaining against the phosphorylated proteins pERK1/2, pSMAD3 and pSMAD1/5/9 in both human and mouse ACP. We reveal that inhibiting the MAPK/ERK pathway with trametinib, a clinically approved MEK inhibitor, results in reduced proliferation and increased apoptosis in explant cultures of human and mouse ACP. Finally, we analyse a prominent molecular signature in the glial reactive tissue to characterise the inflammatory microenvironment and uncover the activation of inflammasomes in human ACP. We validate these results by immunostaining against immune cell markers, cytokine ELISA and proteome analysis in both solid tumour and cystic fluid from ACP patients. Our data support a new molecular paradigm for understanding ACP tumorigenesis as an aberrant mimic of natural tooth development and opens new therapeutic opportunities by revealing the activation of the MAPK/ERK and inflammasome pathways in human ACP.
Approach to the Patient With Hypothalamic Obesity
Abstract Hypothalamic obesity (HO) is defined as abnormal weight gain due to physical destruction of the hypothalamus. Suprasellar tumors, most commonly craniopharyngiomas, are a classic cause of HO. HO often goes unnoticed initially as patients, families, and medical teams are focused on oncologic treatments and management of panhypopituitarism. HO is characterized by rapid weight gain in the first year after hypothalamic destruction followed by refractory obesity due to an energy imbalance of decreased energy expenditure without decreased food intake. Currently available pharmacotherapies are less effective in HO than in common obesity. While not a cure, dietary interventions, pharmacotherapy, and bariatric surgery can mitigate the effects of HO. Early recognition of HO is necessary to give an opportunity to intervene before substantial weight gain occurs. Our goal for this article is to review the pathophysiology of HO and to discuss available treatment options and future directions for prevention and treatment.
Tumor features in adult papillary and adamantinomatous craniopharyngioma: neuroradiological evaluation of pituitary-hypothalamic-axis dysfunction and outcome prediction
PurposeTo identify radiological features distinguishing adamantinomatous craniopharyngioma (ACP) from papillary craniopharyngioma (PCP) and assess their impact on pituitary-hypothalamic-axis dysfunction and post-surgery recurrence.MethodsMRIs of 80 patients (48 with ACP, 32 with PCP) were analyzed for tumor topography, size, cystic-solid composition, peritumoral edema, signal intensity, and CT for calcification patterns. Volumes, normalized signal intensity minimum (nT2min) and maximum (nT1Max) values were measured from T2 and T1-weighted images, respectively. These variables were correlated with pituitary-hypothalamic-axis dysfunction and surgical outcomes.ResultsThere were no significant topographic differences between ACP and PCP (P > 0.85). ACP tumors had larger volumes (4992.2 ± 5195.5 mm³ vs. 814.4 ± 1023 mm³), a predominant cystic component, lower nT2min values (42.57% vs. 55.55%), higher nT1Max values (273.25% vs. 216.67%), and more peripheral calcifications (P < 0.001). In ACP lower nT2min and higher nT1Max values correlated with incomplete surgical excision (nT2min: P < 0.001, r = -0.607; nT1Max: P < 0.001, r = 0.817) while only lower nT2min values correlated with higher recurrence likelihood (nT2min: P < 0.001, r = -0.485). Regardless of histotype, tumors invading the third ventricle floor were more likely to show peritumoral edema (P < 0.001), hypothalamic infiltration (P < 0.001), and dysfunction (P = 0.013).ConclusionTumor location relative to the third ventricle and associated parenchymal changes are independent predictors of hypothalamic dysfunction, regardless of tumor histotype. ACP’s cystic composition characterized by a higher concentration of thick or proteinaceous material and peripheral calcifications predict poorer surgical outcomes.
The clinical significance of inflammatory mediators in predicting obesity and progression-free survival in patients with adult-onset Craniopharyngioma
Background Craniopharyngioma (CP) is a rare malformational tumor characterized by high rates of recurrence and morbid obesity. However, the role of inflammatory mediators in obesity and the prognosis of patients with CP remains unknown. Therefore, the present study aimed to analyze associations of inflammatory mediators with weight-related outcomes and the prognosis of patients with CP. Methods A total of 130 consecutive patients with CP were included in this study. The expression levels of seven inflammatory mediators and the plasma leptin concentration were investigated. Clinical parameters, weight changes, new-onset obesity, and progression-free survival (PFS) were recorded. The relationships between inflammatory mediators, clinicopathologic parameters, weight-related outcomes, and PFS were explored. Results Compared with those in normal pituitary tissue, the expressions of inflammatory mediators in tumor tissue were higher. Higher expression levels of CXCL1 and CXCL8 were identified as independent risk factors for significant weight gain, and CXCL1 and TNF were identified as independent risk factors for new-onset postoperative obesity. Poor PFS was associated with higher expression levels of CXCL1, CXCL8, IL1A, IL6, and TNF. Conclusion The present study revealed that inflammatory mediators are associated with morbid obesity in patients with CP. Inflammatory mediators may be the critical bridge between elevated leptin and weight-related outcomes. Additionally, PFS was associated with the expression of inflammatory mediators. Further research is needed to elucidate the underlying mechanisms of inflammatory mediators and their potential as targets for novel therapies for CP.
The role of BRAF testing of Rathke’s cleft cysts to identify missed papillary craniopharyngioma
Aim The differential diagnosis of cystic sellar/suprasellar lesions includes craniopharyngioma (CP) and Rathke’s cleft cyst (RCC). Histological differentiation between cystic papillary craniopharyngioma (pCP) and RCC using light microscopy alone is challenging. A major point of difference is that virtually all pCPs are clonal for the BRAF V600E variant, whereas RCCs are not. Noting that BRAF testing of RCCs is not current standard practice, we hypothesised that routinely performing BRAF studies in RCCs might uncover otherwise missed pCPs. Method We performed a retrospective cohort study of all RCCs operated on at Flinders Medical Centre, the Memorial and Royal Adelaide Hospitals, between 2001 and 2023. In cases with sufficient tissue, we performed BRAF V600E immunohistochemistry (IHC) and BRAF next generation sequencing (NGS) of extracted tumour DNA. Results Of eleven patients with suitable operative specimens, one patient with an initial diagnosis of RCC was revised to pCP following BRAF testing with equivocal positivity on BRAF IHC and clear identification of the V600E variant on NGS. The patient’s subsequent clinical course was aggressive and more compatible with pCP than RCC. Conclusion This study highlights the potential value of BRAF testing in RCCs to identify missed pCP, which is an especially timely finding given the advent of primary medical therapy with BRAF inhibition for pCP. In the absence of guidelines advising on the use of BRAF studies in sellar lesions, we suggest consideration of BRAF testing of all RCCs, particularly if there is squamous metaplasia or disease recurrence.
Galactose‐modified duocarmycin prodrugs as senolytics
Senescence is a stable growth arrest that impairs the replication of damaged, old or preneoplastic cells, therefore contributing to tissue homeostasis. Senescent cells accumulate during ageing and are associated with cancer, fibrosis and many age‐related pathologies. Recent evidence suggests that the selective elimination of senescent cells can be effective on the treatment of many of these senescence‐associated diseases. A universal characteristic of senescent cells is that they display elevated activity of the lysosomal β‐galactosidase, and this has been exploited as a marker for senescence (senescence‐associated β‐galactosidase activity). Consequently, we hypothesized that galactose‐modified cytotoxic prodrugs will be preferentially processed by senescent cells, resulting in their selective killing. Here, we show that different galactose‐modified duocarmycin (GMD) derivatives preferentially kill senescent cells. GMD prodrugs induce selective apoptosis of senescent cells in a lysosomal β‐galactosidase (GLB1)‐dependent manner. GMD prodrugs can eliminate a broad range of senescent cells in culture, and treatment with a GMD prodrug enhances the elimination of bystander senescent cells that accumulate upon whole‐body irradiation treatment of mice. Moreover, taking advantage of a mouse model of adamantinomatous craniopharyngioma (ACP), we show that treatment with a GMD prodrug selectively reduced the number of β‐catenin‐positive preneoplastic senescent cells. In summary, the above results make a case for testing the potential of galactose‐modified duocarmycin prodrugs to treat senescence‐related pathologies. Galactose‐modified duocarmycin prodrugs get preferentially processed in senescent cells and behave as senolytics.
Rathke's Cleft Cyst and Craniopharyngioma: A Continuum of the Same Spectrum? Insights from an Interesting Case and Previous Literature
Rathke's Cleft Cysts (RCCs) and Craniopharyngiomas (CPs) may represent disease entities on the same etio-pathological spectrum. We report the case of a 36-year-old female presenting with vision loss and menstrual irregularities, imaging shows a predominantly cystic lesion in the sellar region with suprasellar extension. She underwent a microscopic transnasal resection of the lesion. She later presented with recurrent symptoms and increased residual lesion size on imaging, a transcranial excision of the lesion was performed. Histopathology from the initial operative specimen revealed RCC with squamous metaplasia which was BRAF negative, while the specimen from the second surgery revealed BRAF positive papillary stratified squamous architecture suggestive of Papillary CP. This case adds to the evidence that both RCCs and papillary CPs may be the spectrum of the same disease. Further, papillary CPs may be an evolution from the RCCs.
Craniopharyngioma
Craniopharyngiomas are rare malformational tumours of low histological malignancy arising along the craniopharyngeal duct. The two histological subtypes, adamantinomatous craniopharyngioma (ACP) and papillary craniopharyngioma (PCP), differ in genesis and age distribution. ACPs are diagnosed with a bimodal peak of incidence (5–15 years and 45–60 years), whereas PCPs are restricted to adults mainly in the fifth and sixth decades of life. ACPs are driven by somatic mutations in CTNNB1 (encoding β-catenin) that affect β-catenin stability and are predominantly cystic in appearance. PCPs frequently harbour somatic BRAF V600E mutations and are typically solid tumours. Clinical manifestations due to increased intracranial pressure, visual impairment and endocrine deficiencies should prompt imaging investigations, preferentially MRI. Treatment comprises neurosurgery and radiotherapy; intracystic chemotherapy is used in monocystic ACP. Although long-term survival is high, quality of life and neuropsychological function are frequently impaired due to the close anatomical proximity to the optic chiasm, hypothalamus and pituitary gland. Indeed, hypothalamic involvement and treatment-related hypothalamic lesions frequently result in hypothalamic obesity, physical fatigue and psychosocial deficits. Given the rarity of these tumours, efforts to optimize infrastructure and international collaboration should be research priorities. Craniopharyngiomas are rare malformational intracranial tumours that arise along the craniopharyngeal duct. This Primer describes their formation, diagnosis and treatment, distinguishing between the two histological subtypes — adamantinomatous craniopharyngioma and papillary craniopharyngioma.