The Inflammatory Milieu of Adamantinomatous Craniopharyngioma and Its Implications for Treatment

The oxytocin system in patients with craniopharyngioma: A systematic review

Craniopharyngioma is a benign tumour affecting the hypothalamic and pituitary regions, which are involved in the production and secretion of oxytocin. We conducted a systematic review to assess dysregulation of the oxytocin system in craniopharyngioma and associations with neurobehavioural, eating, and metabolic abnormalities. Eight studies (n = 72 patients) were included. Evidence for dysfunction of the endogenous oxytocin system in craniopharyngioma is limited and mixed. While no significant differences in baseline salivary oxytocin concentrations were reported between patients with craniopharyngioma and controls, patients with craniopharyngioma were found to have blunted salivary oxytocin response following exercise stimulation and this was associated with greater state anxiety and higher BMI. Studies administering exogenous oxytocin are sparse and do not meet required standards. Hypothalamic damage may pose an additional mechanism of oxytocin dysregulation. Improving understanding of the oxytocin system in craniopharyngioma could be pivotal for exploring the potential therapeutic role of exogenous oxytocin in this condition.

Differential proteomic profiles of exosomes in pediatric and adult adamantinomatous craniopharyngioma cyst fluid

BACKGROUND

Adamantinomatous craniopharyngiomas (ACPs), commonly seen in pediatrics and adults often present with large cystic cavities that can compress surrounding tissues, causing severe visual and endocrine symptoms. Complete resection of cystic ACP is challenging, frequently leading to postoperative recurrence. The composition of the cystic fluid is complex, and to date, there has been limited research focusing on exosomes within ACP cyst fluid.

METHODS

We collected cyst fluid from 12 ACP patients and confirmed the presence of exosomes. Subsequently, we conducted exosomal proteomic analysis using LC-MS/MS. The patients were divided into pediatric and adult groups for the analysis of differential protein enrichment, followed by comprehensive bioinformatics analysis, including GO analysis, KEGG analysis, and PPI network analysis, among other functional pathway and protein interaction analyses. Immunohistochemistry was used to determine the tissue expression distribution of the differential protein APOA1.

RESULTS

In our data analysis, 64 significantly differentially expressed proteins were identified, with 37 being overexpressed in the pediatric group and 27 in the adult group. Our results revealed that exosomal proteins in the pediatric group were predominantly enriched in modules and pathways related to high-density lipoprotein particle, apolipoprotein receptor binding, and the PPAR signaling pathway. Additionally, APOA1, as the hub protein with the highest connectivity in the differential protein interaction network, may play a critical role in β-amyloid metabolism pathways in pediatric ACP.

CONCLUSION

This study is the first to construct a proteomic map of ACP cyst fluid exosomes, suggesting significant differences in the tumor microenvironment's lipid metabolism between pediatrics and adults.

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.

Analysis of KLRB1-Mediated Immunosuppressive Regulation in Adamantinomatous Craniopharyngioma

BACKGROUND

 Adamantinomatous craniopharyngioma (ACP) is the most common type of craniopharyngioma (CP). Under the current surgery and/or radiotherapy strategies, the survival rate is high, but the long-term quality of life is poor because of the relationship between the hypothalamic-pituitary axis and the tumor. Many studies had shown that endocrine deficiencies caused by craniopharyngiomas of the hypothalamic-pituitary axis persist throughout almost the entire life of the patients after surgery, requiring them to receive hormone replacement therapy. Thus, we need to explore new treatments to improve the prognosis of patients. In recent years, there are more and more studies on the immunotherapy of various tumors. However, due to the rarity of the disease, immunotherapy for ACP is rarely researched. The discovery of the tumor immune-suppressive checkpoint KLRB1 (killer cell lectinlike receptor B1), which encodes CD161, may provide a novel target for the treatment of ACP.

METHODS

 Data analysis of retrospective RNA sequencing was conducted in a cohort of 51 pediatric samples in the GSE94349 dataset, and the results were well validated in the GSE68015 dataset including 31 pediatric samples. We used R language as the main tool for statistical analysis and graphical work.

RESULTS

 Our research showed that KLRB1 was enriched in ACP. Additionally, the expression of KLRB1 was positively related to immune functions and most inflammatory responses of ACP. We found that most of the T lineage-related immune responses were positively correlated with KLRB1 expression, and KLRB1 played an important role in the activation of inflammatory processes.

CONCLUSIONS

 KLRB1 is a promising target for immunotherapeutic strategies.

Childhood craniopharyngioma: a retrospective study of children followed in Hôpital Universitaire de Bruxelles

Introduction

Craniopharyngiomas (CPs) are benign brain tumors accounting for 5 - 11% of intracranial tumors in children. These tumors often recur and can cause severe morbidity. Postoperative radiotherapy efficiently controls and prevents progression and recurrence. Despite advancements in neurosurgery, endocrinological, visual, and neuropsychological complications are common and significantly lower the quality of life of patients.

Methods

We performed a retrospective study, including all patients younger than sixteen diagnosed with CP between July 1989 and August 2022 and followed up in Hôpital Universitaire de Bruxelles.

Results

Nineteen children with CP were included, with median age of 7 years at first symptoms and 7.5 at diagnosis. Common symptoms at diagnosis were increased intracranial pressure (63%), visual impairment (47%), growth failure (26%), polyuria/polydipsia (16%), and weight gain (10.5%). As clinical signs at diagnosis, growth failure was observed in 11/18 patients, starting with a median lag of 1 year and 4 months before diagnosis. On ophthalmological examination, 27% of patients had papillary edema and 79% had visual impairment. When visual disturbances were found, the average preoperative volume was higher (p=0.039). Only 6/19 patients had gross total surgical resection. After the first neurosurgery, 83% experienced tumor recurrence or progression at a median time of 22 months. Eleven patients (73%) underwent postsurgical radiotherapy. At diagnosis, growth hormone deficiency (GHD) was the most frequent endocrine deficit (8/17) and one year post surgery, AVP deficiency was the most frequent deficit (14/17). Obesity was present in 13% of patients at diagnosis, and in 40% six months after surgery. There was no significant change in body mass index over time (p=0.273) after the first six months post-surgery.

Conclusion

CP is a challenging brain tumor that requires multimodal therapy and lifelong multidisciplinary follow-up including hormonal substitution therapy. Early recognition of symptoms is crucial for prompt surgical management. The management of long-term sequelae and morbidity are crucial parts of the clinical path of the patients. The results of this study highlight the fundamental importance of carrying out a complete assessment (ophthalmological, endocrinological, neurocognitive) at the time of diagnosis and during follow-up so that patients can benefit from the best possible care.

Exploration of the shared pathways and common biomarker in adamantinomatous craniopharyngioma and type 2 diabetes using integrated bioinformatics analysis

Craniopharyngiomas are rare tumors of the central nervous system that typically present with symptoms such as headache and visual impairment, and those reflecting endocrine abnormalities, which seriously affect the quality of life of patients. Patients with craniopharyngiomas are at higher cardiometabolic risk, defined as conditions favoring the development of type 2 diabetes and cardiovascular disease. However, the underlying common pathogenic mechanisms of craniopharyngiomas and type 2 diabetes are not clear. Especially due to the difficulty of conducting in vitro or in vivo experiments on craniopharyngioma, we thought the common pathway analysis between craniopharyngioma and type 2 diabetes based on bioinformatics is a powerful and feasible method. In the present study, using public datasets (GSE94349, GSE68015, GSE38642 and GSE41762) obtained from the GEO database, the gene expression associated with adamantinomatous craniopharyngioma, a subtype of craniopharyngioma, and type 2 diabetes were analyzed using a bioinformatic approach. We found 11 hub genes using a protein-protein interaction network analysis. Of these, seven (DKK1, MMP12, KRT14, PLAU, WNT5B, IKBKB, and FGF19) were also identified by least absolute shrinkage and selection operator analysis. Finally, single-gene validation and receptor operating characteristic analysis revealed that four of these genes (MMP12, PLAU, KRT14, and DKK1) may be involved in the common pathogenetic mechanism of adamantinomatous craniopharyngioma and type 2 diabetes. In addition, we have characterized the differences in immune cell infiltration that characterize these two diseases, providing a reference for further research.

Preoperative peripheral inflammatory markers are predictors of postoperative central diabetes insipidus in craniopharyngioma patients: a retrospective study

BACKGROUND

Postoperative central diabetes insipidus (CDI) is commonly observed in craniopharyngioma (CP) patients, and the inflammatory response plays an important role in CPs. We aimed to evaluate the predictive value of preoperative peripheral inflammatory markers and their combinations regarding CDI occurrence in CPs.

METHODS

The clinical data including preoperative peripheral inflammatory markers of 208 CP patients who underwent surgical treatment were retrospectively collected and analyzed. The preoperative peripheral white blood cells (WBC), neutrophils, lymphocytes, monocytes, platelet (PLT), neutrophil-to-lymphocyte ratio (NLR), derived-NLR (dNLR), monocyte-to-lymphocyte ratio (MLR) and PLT-to-lymphocyte ratio (PLR) were assessed in total 208 CP patients and different age and surgical approach CP patient subgroups. Their predictive values were evaluated by the receiver operator characteristic curve analysis.

RESULTS

Preoperative peripheral WBC, neutrophils, NLR, dNLR, MLR, and PLR were positively correlated and lymphocyte was negatively associated with postoperative CDI occurrence in CP patients, especially when WBC ≥ 6.66 × 109/L or lymphocyte ≤ 1.86 × 109/L. Meanwhile, multiple logistic regression analysis showed that WBC > 6.39 × 109/L in the > 18 yrs age patients, WBC > 6.88 × 109/L or lymphocytes ≤ 1.85 × 109/L in the transcranial approach patients were closely associated with the elevated incidence of postoperative CDI. Furthermore, the area under the curve obtained from the receiver operator characteristic curve analysis showed that the best predictors of inflammatory markers were the NLR in total CP patients, the MLR in the ≤ 18 yrs age group and the transsphenoidal group, the NLR in the > 18 yrs age group and the dNLR in the transcranial group. Notably, the combination index NLR + dNLR demonstrated the most valuable predictor in all groups.

CONCLUSIONS

Preoperative peripheral inflammatory markers, especially WBC, lymphocytes and NLR + dNLR, are promising predictors of postoperative CDI in CPs.

Proteomics study of primary and recurrent adamantinomatous craniopharyngiomas

BACKGROUND

Adamantinomatous craniopharyngiomas (ACPs) are rare benign epithelial tumours with high recurrence and poor prognosis. Biological differences between recurrent and primary ACPs that may be associated with disease recurrence and treatment have yet to be evaluated at the proteomic level. In this study, we aimed to determine the proteomic profiles of paired recurrent and primary ACP, gain biological insight into ACP recurrence, and identify potential targets for ACP treatment.

METHOD

Patients with ACP (n = 15) or Rathke's cleft cyst (RCC; n = 7) who underwent surgery at Sanbo Brain Hospital, Capital Medical University, Beijing, China and received pathological confirmation of ACP or RCC were enrolled in this study. We conducted a proteomic analysis to investigate the characteristics of primary ACP, paired recurrent ACP, and RCC. Western blotting was used to validate our proteomic results and assess the expression of key tumour-associated proteins in recurrent and primary ACPs. Flow cytometry was performed to evaluate the exhaustion of tumour-infiltrating lymphocytes (TILs) in primary and recurrent ACP tissue samples. Immunohistochemical staining for CD3 and PD-L1 was conducted to determine differences in T-cell infiltration and the expression of immunosuppressive molecules between paired primary and recurrent ACP samples.

RESULTS

The bioinformatics analysis showed that proteins differentially expressed between recurrent and primary ACPs were significantly associated with extracellular matrix organisation and interleukin signalling. Cathepsin K, which was upregulated in recurrent ACP compared with that in primary ACP, may play a role in ACP recurrence. High infiltration of T cells and exhaustion of TILs were revealed by the flow cytometry analysis of ACP.

CONCLUSIONS

This study provides a preliminary description of the proteomic differences between primary ACP, recurrent ACP, and RCC. Our findings serve as a resource for craniopharyngioma researchers and may ultimately expand existing knowledge of recurrent ACP and benefit clinical practice.

Multi-omics analysis of adamantinomatous craniopharyngiomas reveals distinct molecular subgroups with prognostic and treatment response significance

BACKGROUND

Adamantinomatous craniopharyngioma (ACP) is the commonest pediatric sellar tumor. No effective drug is available and interpatient heterogeneity is prominent. This study aimed to identify distinct molecular subgroups of ACP based on the multi-omics profiles, imaging findings, and histological features, in order to predict the response to anti-inflammatory treatment and immunotherapies.

METHODS

Totally 142 Chinese cases diagnosed with craniopharyngiomas were profiled, including 119 ACPs and 23 papillary craniopharyngiomas. Whole-exome sequencing (151 tumors, including recurrent ones), RNA sequencing (84 tumors), and DNA methylome profiling (95 tumors) were performed. Consensus clustering and non-negative matrix factorization were used for subgrouping, and Cox regression were utilized for prognostic evaluation, respectively.

RESULTS

Three distinct molecular subgroups were identified: WNT, ImA, and ImB. The WNT subgroup showed higher Wnt/β-catenin pathway activity, with a greater number of epithelial cells and more predominantly solid tumors. The ImA and ImB subgroups had activated inflammatory and interferon response pathways, with enhanced immune cell infiltration and more predominantly cystic tumors. Mitogen-activated protein kinases (MEK/MAPK) signaling was activated only in ImA samples, while IL-6 and epithelial-mesenchymal transition biomarkers were highly expressed in the ImB group, mostly consisting of children. The degree of astrogliosis was significantly elevated in the ImA group, with severe finger-like protrusions at the invasive front of the tumor. The molecular subgrouping was an independent prognostic factor, with the WNT group having longer event-free survival than ImB (Cox, P = 0.04). ImA/ImB cases were more likely to respond to immune checkpoint blockade (ICB) therapy than the WNT group ( P <0.01). In the preliminary screening of subtyping markers, CD38 was significantly downregulated in WNT compared with ImA and ImB ( P = 0.01).

CONCLUSIONS

ACP comprises three molecular subtypes with distinct imaging and histological features. The prognosis of the WNT type is better than that of the ImB group, which is more likely to benefit from the ICB treatment.

Pediatric Neuro-oncology

OBJECTIVE

This article reviews the most common pediatric brain tumors, neurocutaneous syndromes, treatment-related neurotoxicities, and the long-term outcomes of survivors.

LATEST DEVELOPMENTS

In the era of molecular diagnostics, the classification, management, and prognostication of pediatric brain tumors and neurocutaneous syndromes has been refined, resulting in advancements in patient management. Molecular diagnostics have been incorporated into the most recent World Health Organization 2021 classification. This knowledge has allowed for novel therapeutic approaches targeting the biology of these tumors with the intent to improve overall survival, decrease treatment-related morbidity, and improve quality of life. Advances in management have led to better survival, but mortality remains high and significant morbidity persists. Current clinical trials focus on tumor biology targeted therapy, deescalation of therapy, and multimodal intensified approaches with targeted therapy in more high-risk tumors.

ESSENTIAL POINTS

Molecular diagnostics for pediatric brain tumors and neurocutaneous syndromes have led to novel therapeutic approaches targeting the biology of these tumors with the goals of improving overall survival and decreasing treatment-related morbidity. Further understanding will lead to continued refinement and improvement of tumor classification, management, and prognostication.

Revealing Pan-Histology Immunomodulatory Targets in Pediatric Central Nervous System Tumors

BACKGROUND

The application of immunotherapy for pediatric CNS malignancies has been limited by the poorly understood immune landscape in this context. The aim of this study was to uncover the mechanisms of immune suppression common among pediatric brain tumors.

METHODS

We apply an immunologic clustering algorithm validated by The Cancer Genome Atlas Project to an independent pediatric CNS transcriptomic dataset. Within the clusters, the mechanisms of immunosuppression are explored via tumor microenvironment deconvolution and survival analyses to identify relevant immunosuppressive genes with translational relevance.

RESULTS

High-grade diseases fall predominantly within an immunosuppressive subtype (C4) that independently lowers overall survival time and where common immune checkpoints (e.g., PDL1, CTLA4) are less relevant. Instead, we identify several alternative immunomodulatory targets with relevance across histologic diseases. Specifically, we show how the mechanism of EZH2 inhibition to enhance tumor immunogenicity in vitro via the upregulation of MHC class 1 is applicable to a pediatric CNS oncologic context. Meanwhile, we identify that the C3 (inflammatory) immune subtype is more common in low-grade diseases and find that immune checkpoint inhibition may be an effective way to curb progression for this subset.

CONCLUSIONS

Three predominant immunologic clusters are identified across pediatric brain tumors. Among high-risk diseases, the predominant immune cluster is associated with recurrent immunomodulatory genes that influence immune infiltrate, including a subset that impacts survival across histologies.

Adamantinomatous craniopharyngioma: evolution in the management

BACKGROUND

In spite of the continuous progresses in pediatric neurosurgery, adamantinomatous craniopharyngioma (AC) remains a challenging tumor due to its proximity to optic pathways, pituitary gland, hypothalamus, and Willis' circle, which can result in significant endocrine, cognitive, and neurological morbidity after treatment with subsequent impact on the patient's quality of life (QoL). The relevance that QoL has today explains the changes in the management of AC observed over the time. The goal of the present article is to provide a historical background, to show the milestones in the changes of the AC treatment, and to analyze the current main options to manage such a challenging tumor.

MATERIAL AND METHODS

The pertinent literature has been reviewed. Moreover, a comparison between the past and recent personal series is reported.

RESULTS

Three main eras have been identified. The first (named Cushing era) was characterized by the need to realize a harmless surgery and to define the best way to approach AC; the second (microscope era) was characterized by a tremendous technical and technological development, with remarkable results in term of safe tumor resection and control but relatively poor QoL outcomes; and the third one (current period) is characterized by an increasing integration between surgery and adjuvant treatments, with relatively minor tumor control but significant improvement of QoL (comparable overall survival). The authors' experience reflects these changes. Two groups of children were compared: 52 cases (mean follow-up: 17.5 years) belong to the historical series (group 1, 1985-2003, aggressive surgical management) and 41 (mean follow-up: 8.5 years) to the current one (Group 2, 2004-2021, integrated management). No significant differences between the two groups were detected about recurrence rate, surgical mortality, and overall survival. However, Group 2 showed significant lower rates of postoperative panhypopituitarism, obesity, and visual deterioration.

CONCLUSIONS

Radical surgery allows for a good AC control with a low rate of recurrence but high risk of permanent morbidity. Despite the greater number of recurrences and surgeries, the more conservative policy, based on a combination of treatments, seems to provide the same tumor control with a better QoL. The advances in trans-nasal and trans-ventricular endoscopy, in proton therapy and in the management of the AC cyst are the main factors that allowed such an improvement.

Transcription Factor GLI1 Induces IL-6-Mediated Inflammatory Response and Facilitates the Progression of Adamantinomatous Craniopharyngioma

Adamantinomatous craniopharyngioma (ACP) is a neuroendocrine tumor whose pathogenesis remains unclear. This study investigated the role of glioma-associated oncogene family zinc finger 1 (GLI1), a transcription factor in the sonic hedgehog (SHH) signaling pathway, in ACP. We discovered that GLI1 regulates the expression of IL-6, thereby triggering inflammatory responses in ACP and influencing the tumor's progression. Analyzing the Gene Expression Omnibus (GEO) database chip GSE68015, we found that GLI1 is overexpressed in ACP, correlating positively with the spite of ACP and inflammation markers. Knockdown of GLI1 significantly inhibited the levels of tumor necrosis factor α, interleukin-6 (IL-6), and IL-1β in ACP cells, as well as cell proliferation and migration. We further identified a binding site between GLI1 and the promoter region of IL-6, demonstrating that GLI1 can enhance the expression of IL-6. These findings were verified in vivo, where activation of the SHH pathway significantly promoted GLI1 and IL-6 expressions in nude mice, inducing inflammation and tumor growth. Conversely, GLI1 knockdown markedly suppressed these processes. Our study uncovers a potential molecular mechanism for the occurrence of inflammatory responses and tumor progression in ACP.

OpenPBTA: The Open Pediatric Brain Tumor Atlas

Pediatric brain and spinal cancers are collectively the leading disease-related cause of death in children; thus, we urgently need curative therapeutic strategies for these tumors. To accelerate such discoveries, the Children's Brain Tumor Network (CBTN) and Pacific Pediatric Neuro-Oncology Consortium (PNOC) created a systematic process for tumor biobanking, model generation, and sequencing with immediate access to harmonized data. We leverage these data to establish OpenPBTA, an open collaborative project with over 40 scalable analysis modules that genomically characterize 1,074 pediatric brain tumors. Transcriptomic classification reveals universal TP53 dysregulation in mismatch repair-deficient hypermutant high-grade gliomas and TP53 loss as a significant marker for poor overall survival in ependymomas and H3 K28-mutant diffuse midline gliomas. Already being actively applied to other pediatric cancers and PNOC molecular tumor board decision-making, OpenPBTA is an invaluable resource to the pediatric oncology community.

Expression of S100A9 in adamantinomatous craniopharyngioma and its association with wet keratin formation

Wet keratin is a hallmark of adamantinomatous craniopharyngioma (ACP), which is frequently infiltrated by inflammatory cells. S100 calcium-binding protein A9 (S100A9) has been confirmed to play a decisive role in the development of inflammation. However, the relationship between wet keratin (keratin nodules) and S100A9 in ACP is poorly understood. The objective of the present study was to explore the expression of S100A9 in ACP and its association with wet keratin formation. Immunohistochemistry and immunofluorescence were used to detect the expression of S100A9, β-catenin and Ki67 in 46 cases of ACP. A total of three online databases were used to analyze S100A9 gene expression and protein data. The results revealed that S100A9 was primarily expressed in wet keratin and some intratumoral and peritumoral cells, and its expression in wet keratin was upregulated in the high inflammation group (P=1.800x10^-3). In addition, S100A9 was correlated with the degree of inflammation (r=0.6; P=7.412x10^-3) and the percentage of Ki67-positive cells (r=0.37; P=1.000x10^-2). In addition, a significant correlation was noted between the area of wet keratin and the degree of inflammation (r=0.51; P=2.500x10^-4). In conclusion, the present study showed that S100A9 was upregulated in ACP and may be closely associated with wet keratin formation and the infiltration of inflammatory cells in ACP.

Precision based approach to tailoring radiotherapy in the multidisciplinary management of pediatric central nervous system tumors

Modern day survivorship from childhood malignancies is estimated to be over 80%. However, central nervous system tumors remain the leading cause of cancer mortality in children and is the most common solid tumor in this population. Improved survivorship is, in part, a result of improved multidisciplinary care, often with a combination of surgery, radiation therapy, and systemic therapy. With improved survival, long term effects of treatment and quality of life impacts have been recognized and pose a challenge to maximize the therapeutic ratio of treatment. It has been increasingly more apparent that precise risk stratification, such as with the inclusion of molecular classification, is instrumental in efforts to tailor radiotherapy for appropriate treatment, generally towards de-intensification for this vulnerable patient population. In addition, advances in radiotherapy techniques have allowed greater conformality and accuracy of treatment for those who do require radiotherapy for tumor control. Ongoing efforts to tailor radiotherapy, including de-escalation, omission, or intensification of radiotherapy, continue to improve as increasing insight into tumor heterogeneity is recognized, coupled with advances in precision medicine employing novel molecularly-targeted therapeutics.

Single-cell RNA sequencing highlights intratumor heterogeneity and intercellular network featured in adamantinomatous craniopharyngioma

Despite improvements in microscopically neurosurgical techniques made in recent years, the prognosis of adamantinomatous craniopharyngioma (ACP) is still unsatisfactory. Little is known about cellular atlas and biological features of ACP. Here, we carried out integrative analysis of 44,038 single-cell transcriptome profiles to characterize the landscape of intratumoral heterogeneity and tumor microenvironment (TME) in ACP. Four major neoplastic cell states with distinctive expression signatures were defined, which further revealed the histopathological features and elucidated unknown cellular atlas of ACP. Pseudotime analyses suggested potential evolutionary trajectories between specific neoplastic cell states. Notably, a distinct oligodendrocyte lineage was identified in ACP, which was associated with immunological infiltration and neural damage. In addition, we described a tumor-centric regulatory network based on intercellular communication in TME. Together, our findings represent a unique resource for deciphering tumor heterogeneity of ACP, which will improve clinical diagnosis and treatment strategies.

Current Advances in Papillary Craniopharyngioma: State-Of-The-Art Therapies and Overview of the Literature

Craniopharyngiomas are commonly classified as low-grade tumors, although they may harbor a malignant behavior due to their high rate of recurrence and long-term morbidity. Craniopharyngiomas are classically distinguished into two histological types (adamantinomatous and papillary), which have been recently considered by the WHO classification of CNS tumors as two independent entities, due to different epidemiological, radiological, histopathological, and genetic patterns. With regard to papillary craniopharyngioma, a BRAF V600 mutation is detected in 95% of cases. This genetic feature is opening new frontiers in the treatment of these tumors using an adjuvant or, in selected cases, a neo-adjuvant approach. In this article, we present an overview of the more recent literature, focusing on the specificities and the role of oncological treatment in the management of papillary craniopharyngiomas. Based on our research and experience, we strongly suggest a multimodal approach combining clinical, endocrinological, radiological, histological, and oncological findings in both preoperative workup and postoperative follow up to define a roadmap integrating every aspect of this challenging condition.

Molecular biological features of cyst wall of adamantinomatous craniopharyngioma

The molecular biological differences between cyst walls and those in solid bodies are the foundation of the outcomes. In this study, the CTNNB1 mutations were confirmed by DNAsequencing; CTNNB1 expression levels were detected by PCR; the differences between solid bodies and cyst walls in proliferative capacity and tumor stem cell niches were assessed by immunohistochemistry; the effect of the residual cyst wall on recurrence was assessed by follow-up. Mutations in the CTNNB1 in the cyst wall and the solid body were identical in each case. No differences were found in the transcriptional level of CTNNB1 between the cyst walls and the solid bodies (P = 0.7619). The cyst wall showed a pathological structure similar to the solid body. Proliferative capacity of cyst walls was stronger than that of solid body (P = 0.0021), and β-catenin nuclear positive cells (cell clusters) in cyst walls were more than that in solid tumor (P = 0.0002). The retrospective 45 ACPs showed residual cyst wall was significantly associated with tumor recurrence or regrowth (P = 0.0176). Kaplan-Meier analysis showed there was a significant difference in the prognosis between GTR and STR (P < 0.0001).The cyst wall of ACP contained more tumor stem cell niches which could lead to the recurrence. According to the above-mentioned, a special attention to the management of the cyst wall should be paid.

Response assessment in pediatric craniopharyngioma: recommendations from the Response Assessment in Pediatric Neuro-Oncology (RAPNO) Working Group

BACKGROUND

Craniopharyngioma is a histologically benign tumor of the suprasellar region for which survival is excellent but quality of life is often poor secondary to functional deficits from tumor and treatment. Standard therapy consists of maximal safe resection with or without radiation therapy. Few prospective trials have been performed, and response assessment has not been standardized.

METHODS

The Response Assessment in Pediatric Neuro-Oncology (RAPNO) committee devised consensus guidelines to assess craniopharyngioma response prospectively.

RESULTS

Magnetic resonance imaging is the recommended radiologic modality for baseline and follow-up assessments. Radiologic response is defined by 2-dimensional measurements of both solid and cystic tumor components. In certain clinical contexts, response to solid and cystic disease may be differentially considered based on their unique natural histories and responses to treatment. Importantly, the committee incorporated functional endpoints related to neuro-endocrine and visual assessments into craniopharyngioma response definitions. In most circumstances, the cystic disease should be considered progressive only if growth is associated with acute, new-onset or progressive functional impairment.

CONCLUSIONS

Craniopharyngioma is a common pediatric central nervous system tumor for which standardized response parameters have not been defined. A RAPNO committee devised guidelines for craniopharyngioma assessment to uniformly define response in future prospective trials.

Immune infiltration in aggressive papillary craniopharyngioma: High infiltration but low action

Papillary craniopharyngiomas (PCPs) are biologically benign but clinically aggressive lesions hence affect the quality of life. The expression of inflammatory mediators and regulation of the immune microenvironment in PCPs have not been investigated much. In this study, for the first time, we assessed the immune cell infiltration and immune cell signatures in PCPs by analyzing the bulk-RNA sequencing data and immunohistochemical staining. Additionally, we performed qRT-PCR analysis to detect inflammatory mediators interleukin-1α (IL1A) and interleukin-6 (IL6) in different aggressive groups and then developed the IL1A and IL6 prediction models for defining the degree of hypothalamic invasion. Lastly, we defined differentially expressed genes related to invasiveness and implemented enrichment analysis to them. Our results indicated that PCPs are in a state of high immune infiltration but low action with abundant inflammatory cells. High infiltration of neutrophils may lead a low active immune microenvironment. Furthermore, the high expression level of IL1A and IL6 was positively correlated with the invasion of PCP tumors in the hypothalamus. These findings provide new pathological insights into the underlying mechanism of the immune microenvironment in PCP tumors. Moreover, IL1A and IL6 might serve as potential therapeutic targets for PCP tumors, especially to prevent their invasion into the hypothalamus.

A Rare Case of Adamantinomatous Craniopharyngioma in an Adult

Craniopharyngiomas represent a rare group of intracranial tumors that often arise in the sellar/suprasellar region of the brain. Adamantinomatous craniopharyngioma is significantly more common than papillary craniopharyngioma. The former most often arises in children whereas the papillary craniopharyngioma is mainly limited to adults. We present the case of a 34-year-old female with visual disturbances and other vague complaints who was found to have a large lobulated sellar mass on neuroimaging studies. She was subsequently diagnosed with an adamantinomatous craniopharyngioma after undergoing transsphenoidal resection. We discuss the patient's clinical, radiological, and pathological findings in correlation with the current literature and recommendations regarding this type of tumor. Given that adamantinomatous craniopharyngioma rarely presents in adulthood, especially in middle-aged adults, this case is considered rare, and we hope to increase awareness to include adamantinomatous craniopharyngioma in the differential diagnosis for sellar lesions in this age group.

Integrative analyses identify HIF-1α as a potential protective role with immune cell infiltration in adamantinomatous craniopharyngioma

Craniopharyngiomas (CPs) are histologically benign tumors located in the sellar–suprasellar region. Although the transcriptome development in recent years have deepened our knowledge to the tumorigenesis process of adamantinomatous craniopharyngioma (ACP), the peritumoral immune infiltration of tumor is still not well understood. In this study, weighted gene coexpression network analysis (WGCNA) was applied to identify different gene modules based on clinical characteristics and gene expression, and then, the protein–protein interaction (PPI) network with the Cytohubba plug-in were performed to screen pivotal genes. In addition, immune cell infiltration (ICI) analysis was used to evaluate the immune microenvironment of ACP patients. In total, 8,568 differential expression genes were identified based on our datasets and two microarray profiles from the public database. The functional enrichment analysis revealed that upregulated genes were mainly enriched in immune-related pathways while downregulated genes were shown in the hormone and transduction of signaling pathways. The WGCNA investigated the most relevant modules, and 1,858 hub genes was detected, from which the PPI network identified 14 pivotal genes, and the Hypoxia-inducible factor 1-alpha (HIF-1α) pathway including four critical genes may be involved in the development of ACP. Moreover, naïve CD4+ and CD8+ T cells were decreased while specific subtypes of T cells were significantly increased in ACP patients according to ICI analysis. Validation by immunofluorescence staining revealed a higher expression of HIF-1α in ACP (ACP vs. control) and adult-subtype (adult vs. children), suggesting a possible state of immune system activation. Notably, children with low HIF-1α scores were related to the hypothalamus involvement and hydrocephalus symptoms. In this study, we successfully identified HIF-1α as a key role in the tumorigenesis and development of ACP through comprehensive integrated analyses and systematically investigated the potential relationship with immune cells in ACP. The results may provide valuable resources for understanding the underlying mechanisms of ACP and strengthen HIF-1α as a potential immunotherapeutic target in clinical application.

Exploring the pathological relationships between adamantinomatous craniopharyngioma and contiguous structures with tumor origin

PURPOSE

Identifying relationships between craniopharyngiomas (CPs) and contiguous structures, and tumor origin are crucial for treatments. This study attempted to explore the relationships and tumor origin.

METHODS

CPs that underwent endoscopic surgeries were enrolled. The interfacial specimens of CPs attaching the hypothalamus, pituitary stalk (PS), pituitary grand (PG), optic chiasma (OC) and brain tissue (BT) were pathologically examined. Boundaries between CPs and these structures were observed during operations. Expression of β-catenin and stem cell markers were analyzed to explore the tumor origin. Outcomes of patients were assessed.

RESULTS

A total of 34 CPs were categorized into two groups based on the locations of finger-like protrusions (FP). Group A comprised 18 CPs with FP only present in the specimens attaching to hypothalamus. The surface of these CPs was fused with hypothalamus under endoscopic videos. However, the specimens attaching to the PS, PG, OC, and BT showed no FP. Clear boundaries was observed between these CPs and these structures. Group B comprised 16 CPs with FP only present in the specimens attaching to PS. The tumor surface was fused with PS. Specimens attaching to the hypothalamus, PG, OC and BT showed no FP. Clear boundary was observed among these CPs with these structures. These results implied CPs only invaded a certain part of hypothalamic-pituitary axis. β-catenin and stem cells markers mainly distributed in the FP tissues of both groups. Patients in group B achieved better outcomes than group A.

CONCLUSIONS

CPs only invade the hypothalamic-pituitary axis with FP and the FP would be the tumor origin.

Targeted therapies in the medical management of craniopharyngioma

Craniopharyngioma (CP) is an intracranial benign tumor that behaves aggressively due to its location, infiltration of the surrounding nervous tissue and high capacity for recurrence. Treatment of choice is surgery followed or not by radiotherapy. Recent advances in molecular biology techniques and the better understanding of the genetic alterations of the two histological types of CP have open new therapeutic perspectives with targeted drugs. Adamantinomatous CP (ACP) is associated with activating mutations of the CTNNB1 gene. Such mutations are accompanied by intracellular accumulation of β-catenin, an oncogenic protein that activates the intracellular Wnt/ β-catenin signaling pathway, which regulates the transcription of genes involved in cell proliferation. Therefore, the use of molecular therapies directed against the activation of the Wnt/ β-catenin pathway could be an attractive and promising therapeutic option in the management of ACPs. On the other hand, papillary CP (PCP) is associated with activating mutations in the BRAF gene. This gene encodes a BRAF protein that plays an important role in the intracellular mitogen-activated protein kinase (MAPK) signaling pathway, which also regulates cell proliferation. The use of BRAF inhibitors either in monotherapy or in combination with mitogen-activated protein kinase (MEK) inhibitors has demonstrated therapeutic efficacy in isolated clinical cases of relapsed PCPs. A preliminary report of a recent phase II clinical trial has shown a therapeutic response in 93.7% of patients with BRAF ^V600E -mutated PCP, with an 85% reduction in tumor size. In the present review we comment on the efficacy and safety of the different drugs being used in patients with PCP.

Adamantinomatous craniopharyngioma cyst fluid can trigger inflammatory activation of microglia to damage the hypothalamic neurons by inducing the production of β-amyloid

INTRODUCTION

The mechanism by which adamantinomatous craniopharyngioma (ACP) damages the hypothalamus is still unclear. Cyst fluid rich in lipids and inflammatory factors is a characteristic pathological manifestation of ACP and may play a very important role in hypothalamic injury caused by tumors.

OBJECTIVE

The objective of this study was to construct a reliable animal model of ACP cyst fluid-induced hypothalamic injury and explore the specific mechanism of hypothalamic injury caused by cyst fluid.

METHODS

An animal model was established by injecting human ACP cyst fluid into the bilateral hypothalamus of mice. ScRNA-seq was performed on the mice hypothalamus and on an ACP sample to obtain a complete gene expression profile for analysis. Data verification was performed through pathological means.

RESULTS

ACP cystic fluid caused growth retardation and an increased obesity index in mice, affected the expression of the Npy, Fgfr2, Rnpc3, Sst, and Pcsk1n genes that regulate growth and energy metabolism in hypothalamic neurons, and enhanced the cellular interaction of Agrp-Mc3r. ACP cystic fluid significantly caused inflammatory activation of hypothalamic microglia. The cellular interaction of CD74-APP is significantly strengthened between inflammatory activated microglia and hypothalamic neurons. Beta-amyloid, a marker of neurodegenerative diseases, was deposited in the ACP tumor tissues and in the hypothalamus of mice injected with ACP cyst fluid.

CONCLUSION

In this study, a novel animal model of ACP cystic fluid-hypothalamic injury was established. For the first time, it was found that ACP cystic fluid can trigger inflammatory activation of microglia to damage the hypothalamus, which may be related to the upregulation of the CD74-APP interaction and deposition of β-amyloid, implying that there may be a similar mechanism between ACP cystic fluid damage to the hypothalamus and neurodegenerative diseases.

Parafoveal and peripapillary vessel density in pediatric and juvenile craniopharyngioma patients

We assessed the retinal microvascular alterations detected by optical coherence tomography angiography (OCT-A) in pediatric and juvenile craniopharyngioma (CP) patients with chiasmal compression. We included 15 eyes of 15 pediatric or juvenile CP patients and 18 eyes of 18 healthy subjects. The evaluation of vessel density from the superficial retinal capillary plexus (SRCP), the deep retinal capillary plexus, and the radial peripapillary capillary (RPC) segments was obtained by OCT-A. The association between vessel density measures and functional and structural measurements was also analyzed. There were significant reductions in the nasal sector of the SRCP (p < 0.0001) and all sectors of the RPC segment vessel density (nasal, temporal, and superior; p < 0.0001, inferior; p = 0.0015) in CP patients postoperatively compared to the healthy subjects. The peripapillary retinal nerve fiber layer (r = 0.6602, p = 0.0074) and ganglion cell-inner plexiform layer thicknesses (r = 0.7532, p = 0.0030) were associated with RPC segment vessel density. Visual acuity (r = − 0.5517, p = 0.0330) and temporal visual field sensitivity loss (r = 0.5394, p = 0.0465) showed an association with SRCP vessel density. In pediatric and juvenile patients with CP, parafoveal and peripapillary vascular changes following chiasmal compression were observed. The changes in vascular structures were closely related to structural and functional outcomes.

Expression of Insulin-Like Growth Factor Type 1 Receptor Is Linked to Inflammation in Adamantinomatous Craniopharyngioma

INTRODUCTION

Insulin-like growth factor type 1 receptor (IGF1R) is overexpressed in various malignant tumors, which relates to their transformation and recurrence. Craniopharyngioma is a benign tumor with malignant results, often accompanied by a severe inflammatory reaction. However, the relationship between IGF1R expression and the inflammatory response of craniopharyngioma is unclear.

METHODS

We enrolled 85 patients with adamantinomatous craniopharyngioma (ACP) in a study to explore the relationship between IGF1R expression and clinical features of this disease.

RESULTS

Patients in the IGF1R high-expression group had a significantly higher incidence of hypopituitarism, higher recurrence rate, and lower progression-free survival. β-Catenin can further regulate expression of the stem cell marker, CD44, by regulating IGF1R. Using immunofluorescence, we found that tumor stem cell-like cells did not express phosphorylated (p)-ERK, although p-ERK activation was evident in the surrounding cells. Picropodophyllin, a specific inhibitor of IGF1R, increased the expression of p-ERK protein and decreased the transcription level of interleukin-6.

CONCLUSIONS

High expression of IGF1R might promote inflammation of ACP, which might be an unfavorable factor for pituitary function and prognosis. The high expression of IGF1R in tumor stem cell-like cells might inhibit the expression of p-ERK and promote the generation of inflammatory factors. IGF1R plays a stemness maintenance role in ACP and regulates the production of inflammatory factors through a p-ERK pathway, which suggests that targeting IGF1R and p-ERK might provide a new direction for alleviating tumor inflammation.

Treatment of Cystic Craniopharyngiomas: An Update

In spite of the significant technical and technological progress in neurosurgery and the continuous discoveries by the basic research, adamantinomatous craniopharyngioma remains a significant clinical challenge. Actually, the huge size of the tumor, its multiple cystic components, the encasement of Willis' circle and optic pathways, and the invasion of the hypothalamus often prevent its safe surgical resection. Moreover, the local aggressiveness of the tumor accounts for a high risk of recurrence even after a gross total resection. For these reasons, more and more efforts are being dedicated to enhance the knowledge about AC and improve the tools for its treatment.This paper is dedicated to the most recent advances concerning the AC management. Promising, new insights come for the basic research, thanks to the updates on the role of the WNT-β-catenin pathway (important for the tumor genesis and progression, not yet developed enough for a safe target therapy in children but useful for determining the prognosis) and the inflammatory mediators (widely overexpressed, especially by the cyst of the tumor, and for which target therapies are being developed). Moreover, further factors and pathways are under investigation.Also the development of new treatment strategies accounts for the improvement of the prognosis and the quality of life of AC patients. The enhancement of the experience with the endoscopic techniques (both transsphenoidal and transventricular approaches) actually allows to perform a less invasive but effective surgery that can be coupled with new modalities of radiation therapy aiming at obtaining a reliable control of the disease and protecting the endocrinological, ophthalmological, and neurological functions. A special mention is finally deserved by the techniques specifically designed for the intracystic therapy (as cyst fenestration alone or in combination with administration of radionuclides or bleomycin or interferon-α) that are here analyzed together with the aforementioned advances.

A Novel Immune Classification for Predicting Immunotherapy Responsiveness in Patients With Adamantinomatous Craniopharyngioma

Adamantinomatous craniopharyngioma (ACP) is the most common tumor of the sellar region in children. The aggressive behavior of ACP challenges the treatment for it. However, immunotherapy is rarely studied in ACP. In this research, we performed unsupervised cluster analysis on the 725 immune-related genes and arrays of 39 patients with ACP patients in GSE60815 and GSE94349 databases. Two novel immune subtypes were identified, namely immune resistance (IR) subtype and immunogenic (IG) subtype. Interestingly, we found that the ACPs with IG subtype (34.78%, 8/23) were more likely to respond to immunotherapy than the ACPs with IR subtype (6.25%, 1/16) via tumor immune dysfunction and exclusion (TIDE) method. Simultaneously, the enrichment analysis indicated that the differentially expressed genes (DEGs) (p < 0.01, FDR < 0.01) of the IG subtype were chiefly involved in inflammatory and immune responses. However, the DEGs of the IR subtype were mainly involved in RNA processing. Next, immune infiltration analysis revealed a higher proportion of M2 macrophage in the IG subtype than that in the IR subtype. Compared with the IR subtype, the expression levels of immune checkpoint molecules (PD1, PDL1, PDL2, TIM3, CTLA4, Galectin9, LAG3, and CD86) were significantly upregulated in the IG subtype. The ssGSEA results demonstrated that the biofunction of carcinogenesis in the IG subtype was significantly enriched, such as lymphocyte infiltration, mesenchymal phenotype, stemness maintenance, and tumorigenic cytokines, compared with the IR subtype. Finally, a WDR89 (the DEG between IG and IR subtype)-based nomogram model was constructed to predict the immune classification of ACPs with excellent performance. This predictive model provided a reliable classification assessment tool for clinicians and aids treatment decision-making in the clinic.

Clinical features and prognosis of pediatric infradiaphragmatic craniopharyngioma relative to the tumor inflammatory response

BACKGROUND

The relationship between clinical responses in pediatric infradiaphragmatic craniopharyngioma (Q-CP) and inflammatory response is still unclear. The objective of this study was to investigate the clinical significance of tumor inflammatory response in pediatric Q-CPs.

METHODS

The inflammatory response was evaluated by measuring the number of inflammatory cells in the tumor near adenohypophysis junction. The specimens were classified as mild, moderate, or severe based on the number of inflammatory cells. In addition, the levels of pro-inflammatory cytokines and chemokines in the specimens were measured using a cytokine antibody array. Clinical outcomes were analyzed and compared to the markers of inflammatory response.

RESULTS

IL-6 and IL-8 were highly expressed in pediatric Q-CPs, and the transcription level of IL-6 was the highest in the severe group. Most patients (87.3%) had hypopituitarism; the severe inflammation group had an increased incidence of hypopituitarism, which correlated with significantly lower probability of recurrence-free survival and worsened functional status.

CONCLUSIONS

Inflammatory response is common in craniopharyngiomas and is closely related to their biological behavior and the patients' clinical prognosis. Further studies of the relationship between craniopharyngiomas and the inflammatory response will enable the discovery of potential therapeutic targets, which will reduce morbidity and result in better outcomes for pediatric Q-CP patients.

IMPACT

Pediatric infradiaphragmatic craniopharyngiomas are histologically benign brain tumors that often follow an aggressive clinical course. The inflammatory response in craniopharyngioma is common, which is closely related to the biological behavior and clinical prognosis. Several inflammatory and immune markers have been identified in CP; inflammation is an important role in the pathogenesis of hypopituitarism. The aim was to study the relationship between craniopharyngioma and inflammatory response and find potential therapeutic targets can reduce morbidity and result in better outcomes.

Adamantinomatous craniopharyngioma: advances in proteomic research

BACKGROUND

Many efforts have been performed in the last decade to accomplish the genomic and proteomic characterization of pediatric adamantinomatous craniopharyngioma with the purpose to elucidate the molecular mechanisms underlying the onset and development of this pediatric brain tumor, its high recurrence rate, and, although classified as a histologically benign neoplasm, its aggressive behavior.

METHODS

The focus of this review is to perform the new comparison of the proteomic profiles of the solid component and the intracystic fluid of adamantinomatous craniopharyngioma based on our previous results, obtained by both the top-down and the bottom-up proteomic approaches, to disclose differences and similarities, and to discuss the results in the context of the most recent literature.

RESULTS AND CONCLUSIONS

Proteins and peptides identified in the cyst fluid and in the solid component of adamantinomatous craniopharyngioma (AC) include beyond markers of inflammation (i.e., alpha-defensins), proteins involved in cell migration and protein degradation (i.e., beta-thymosin and ubiquitin peptides), whose main role might be in tumor growth and infiltration of the surrounding neural structures. These last appeared different in the solid components compared with the cyst fluid, missing their terminal part in the solid tissue, a feature generally associated to malignancies, which might represent a distinct molecular site for an aggressive behavior of AC.

Craniopharyngioma treatment: an updated summary of important clinicopathological concepts

INTRODUCTION

Craniopharyngiomas (CPs) are benign histological tumors that may develop at different positions along the hypothalamic-pituitary axis. Their close, heterogenous relationship to the hypothalamus makes surgical removal challenging even though this remains the primary treatment strategy.

AREAS COVERED

This article presents a critical overview of the pathological and clinical concepts regarding CPs that should be considered when planning treatment. Thus, we have performed a comprehensive review of detailed CP reports published between 1839 and 2020.

EXPERT OPINION

CP surgery should pursue maximal tumor resection while minimizing the risk of injuring the hypothalamus. Therefore, surgical strategies should be individualized for each patient. Accurate assessment of presenting symptoms and preoperative MRI has proven useful to predict the type of CP-hypothalamus relationship that will be found during surgery. CPs with dense and extensive adhesions to the hypothalamus should be highly suspected when MRI shows the hypothalamus positioned around the mid-third of the tumor and an amputated upper portion of the pituitary stalk. Symptoms related to functional impairment of the infundibulo-tuberal area of the third ventricle floor, such as obesity/hyperphagia, Fröhlich's syndrome, diabetes insipidus, and/or somnolence, also indicate risky CP-hypothalamic adhesions. In these cases, limited tumor removal is strongly advocated followed by radiation therapy.