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Mariarita Santi

Publications and source records attributed to Mariarita Santi.

15 recordsLinked to original sources
PubMed2026

Proteogenomic analysis of pediatric and AYA high-grade glioma reveals age-dependent biology, female-male differences, and kinase targets.

High-grade gliomas (HGGs) in children and adolescents and young adults (AYA) exhibit distinct biology across the neurodevelopmental spectrum. To dissect tumor-intrinsic molecular characteristics independent of developmental variation, we perform comprehensive proteogenomic analyses of tumors from 112 HGG patients aged 0-40 years. Our multi-omics analysis identifies two AYA subgroups-adolescents (aged 15-26 years) and young adults (aged 26-40 years)-with distinct molecular profiles and survival outcomes. Tumor-normal comparisons and survival modeling highlight roles of oxidative phosphorylation and neuronal system biology in glioma progression. Causal network analysis and cell line studies provide a rationale for personalized therapies targeting candidate kinases, such as CDK8. Survival modeling, clustering, and immune-landscape analyses identify proteins, post-translational modifications, and immune signatures linked to outcomes and reveal clinically relevant differences between male and female patients.

adolescent and young adult glioma↗
PubMed2026

High-grade astrocytoma with piloid features: a clinical and genomic analysis of prognostic factors using a large cohort.

BACKGROUND: High-grade astrocytoma with piloid features (HGAP) is a recently defined tumor type that is not well-understood. Prognostic factors of clinical outcomes are not well-established. METHODS: Methylation profiling was performed on tumor samples, many at the National Cancer Institute (NCI) Laboratory of Pathology, and others from publicly available sources. Methylation classifier scores of ≥ 0.90 to the HGAP class on the NCI-Bethesda classifier version 3 were included. Clinical features were collected from the medical record. Survival analyses were performed using the Kaplan-Meier and Cox-proportional hazards methods. RESULTS: The cohort comprised 421 patients. There were high rates of ATRX alteration (62%), CDKN2A/B homozygous loss (78%) and MGMT promoter methylation (53%). MAPK alterations were identified in 74% of evaluable samples. The median age was 46 years, and posterior fossa location was predominant (52%). The median overall survival (OS) was 88 months. Older age (p = 0.01) and the presence of an ATRX alteration (p = 0.04) were found to be negative prognostic factors. The presence of cystic features on magnetic resonance imaging (MRI) was found to be favorably prognostic (p = 0.01). Factors that were not significantly associated with prognosis included histologic high-grade features, CDKN2A/B homozygous deletion, MGMT promoter methylation, extent of resection, and presence of NF1 syndrome. CONCLUSIONS: This large cohort establishes relative frequencies of several important markers. Additionally, older age, the presence of an ATRX alteration, and cystic features on MRI were found to be prognostic. Our work may aid in optimizing treatment regimens for patients with this tumor type.

ATRX alteration↗
PubMed2026

A longitudinal single-cell and spatial multiomic atlas of pediatric high-grade glioma.

Pediatric high-grade glioma (pHGG) is an incurable central nervous system malignancy that is a leading cause of pediatric cancer death. While pHGG shares many similarities with adult glioma, it comprises distinct disease entities. In this study, we longitudinally profile a molecularly diverse cohort of 16 pHGG patients through single-nucleus RNA and ATAC sequencing, whole-genome sequencing, and CODEX spatial proteomics to capture the evolution of neoplastic and microenvironmental features during disease progression and treatment. We define a set of core pHGG neoplastic cell states and observe differential tumor-myeloid interactions between malignant cell phenotypes. We find that essential neuromodulators and the interferon response are upregulated post-therapy, implicating them as malignant cell-intrinsic targets. We observe an increase in oligodendrocytes upon progression and that they coordinate spatial motifs with proneural tumor cells. This multiomic atlas of longitudinal pHGG captures features of therapy response and provides a scalable reference for the study of pediatric brain tumors.

Humans↗
PubMed2006

Evaluation of RB gene and cyclin-dependent kinase inhibitors P21 and P27 in pleomorphic xantoastrocytoma.

Pleomorphic xantoastrocytoma (PXA) is a rare, circumscribed astrocytic tumor that usually occurs in the superficial cerebral hemispheres in children and young adults. Most patients have a favorable prognosis, but recurrence and malignant transformation have been reported. In diffuse gliomas, approximately one third demonstrate mutations of the RB gene. Low expression level and high activity of p27 are known to constitute an independent prognostic factor in patients with malignant gliomas, while p21 expressions have variable labeling ranges. The molecular and genetic basis for tumorigenesis and progression of PXA are still largely unknown. In this study, 13 PXAs were examined immunohistochemically for pRb, p21, and p27 expression. Nine PXAs expressed homogeneous pRb positivity in the most nuclei of the tumor cells. Four cases showed an abnormal pRb staining pattern. All PXAs were positive for nuclear expression of p21. Diffuse nuclear positivity of p27 was seen in 10 cases, focal in 2, and in 1 case was not present. The cases with focal and negative p27 nuclear expression had few pRb-positive nuclei. The majority of PXAs appear to have preserved pRb, p21, and p27 functions. Additional studies are necessary to investigate whether cases with altered pRb and p27 expressions are associated with increased risk of recurrence or malignant transformation.

Astrocytoma↗
PubMed2006

Germinoma: unusual imaging and pathological characteristics. Report of two cases.

Primary germ cell neoplasms of the central nervous system typically develop as midline mass lesions during the first three decades of life. The authors present two cases with atypical clinicopathological features that stimulate discussion on the diagnosis and management of these tumors. The first patient was an 11-year-old boy of Japanese-American heritage who presented with a 6-month-long history of cognitive decline, difficulty swallowing, unsteady gait, and intermittent right-sided posturing. The initial magnetic resonance (MR) image of the brain displayed a mildly increased T2 signal in the cerebral peduncles, putamen, and globus pallidus bilaterally. Follow-up MR images showed an increase in the T2 signal abnormality in the left basal ganglia. The second patient was a 10-year-old Caucasian boy who presented with diabetes insipidus and subsequently displayed progressive fatigue, involuntary eye and mouth movements, and obsessive-compulsive behavior. An MR image demonstrated signs of mineral deposition and foci of increased T2 signal in both basal ganglia. Follow-up MR images demonstrated a progressive increase in the T2 signal (which was then located within the mesial temporal lobe). A biopsy performed on the left thalamic lesion in the first patient revealed a germinoma. The patient was treated with chemotherapy and died 2 years later. The second patient underwent a lumbar puncture, which demonstrated an elevated level of beta-human chorionic gonadotropin. Despite the lack of a mass on MR images in this child, the need for a tissue diagnosis prompted the authors to perform an anterior temporal lobectomy. The diagnosis of diffuse germinoma was confirmed, and the patient was treated with adjunctive chemotherapy. Although uncommon, germ cell tumors can present outside the midline and exhibit a multifocal growth pattern.

Basal Ganglia↗
PubMed2005

Proteomic analysis of apoptotic pathways reveals prognostic factors in follicular lymphoma.

Follicular lymphoma (FL) is the second most common non-Hodgkin's lymphoma and generally is incurable. Reliable prognostic markers to differentiate patients who progress rapidly from those who survive for years with indolent disease have not been established. Most cases overexpress Bcl-2, but the pathogenesis of FL remains incompletely understood. To determine whether a proteomic approach could help overcome these obstacles, we procured lymphoid follicles from 20 cases of FL and 15 cases of benign follicular hyperplasia (FH) using laser capture microdissection. Lysates were spotted on reverse-phase protein microarrays and probed with 21 antibodies to proteins in the intrinsic apoptotic pathway, including those specific for posttranslational modifications such as phosphorylation. A panel of three antibodies [phospho-Akt(Ser473), Bcl-2, and cleaved poly(ADP-ribose) polymerase] segregated most cases of FL from FH. Phospho-Akt(Ser473) and Bcl-2 were significantly increased in FL (P = 0.001 and P < 0.0001, respectively). Additionally, the Bcl-2/Bak ratio completely segregated FL from FH. High ratios of Bcl-2/Bak and Bcl-2/Bax were associated with early death from disease with differences in median survival times of 7.3 years (P = 0.0085) and 3.8 years (P = 0.018), respectively. Using protein microarrays, we identified candidate proteins that may signify clinically relevant molecular events in FL. This approach showed significant changes at the posttranslational level, including Akt phosphorylation, and suggested new prognostic markers, including the Bcl-2/Bak and Bcl-2/Bax ratios. Proteomic end points should be incorporated in larger, multicenter trials to validate the clinical utility of these protein microarray findings.

Adult↗
PubMed2005

Analysis of chromosome 7 in adult and pediatric ependymomas using chromogenic in situ hybridization.

Few studies have yielded reliable data that distinguish between ependymal neoplasms based on molecular genetic attributes. The present study utilizes chromogenic in situ hybridization (CISH), a relatively recent hybridization technique, to retrospectively examine chromosome 7-copy number in pediatric and adult ependymomas. Of the 27 hybridizations, polysomy of chromosome 7 was detected in 10 out of 15 (66%) adult ependymomas, and in only three out of 12 (25%) pediatric lesions. All myxopapillary ependymomas showed polysomy. The remaining tumors were diploid. The authors conclude that (1) there are distinct genetic subsets of ependymoma, in particular, increases in copy number of chromosome 7 are almost exclusively found in myxopapillary ependymoma, and that (2) CISH is a rapid and sensitive method of stratifying morphological variants of ependymoma and potentially other central nervous system (CNS) tumors. These results encourage further investigations with CISH on a larger scale to determine its merit as an ancillary diagnostic and prognostic tool.

Adult↗
PubMed2005

Central nervous system meningiomas in the first two decades of life: a clinicopathological analysis of 87 patients.

OBJECT: The occurrence of meningiomas in children younger than 20 years of age is rare, accounting for less than 3% of all childhood tumors of the central nervous system. The authors of this study sought to add to the limited available information regarding clinicopathological factors that influence outcome, disease progression, and survival in children with meningiomas. METHODS: Eighty-seven cases of childhood meningiomas were identified and classified according to World Health Organization (WHO) 2000 criteria. In addition to the WHO classification, the following potential prognostic factors were analyzed: age, sex, extent of resection, history of radiotherapy, diagnosis of neurofibromatosis Type 2 (NF2) or other inherited syndromes, and the presence of a comorbidity. There was a sex predilection for male patients (35 females and 52 males). Patient age ranged from 5 months to 20 years (mean 14 years). The most common clinical presentations were seizures (33%), headaches (13%), ataxia (10%), and hemiparesis (10%). Nine patients had NF2 and two had Gorlin syndrome. Seven patients had undergone radiotherapy for a prior neoplasm. Tumor location was supratentorial in 64% of the patients, infratentorial in 16%, intraventricular in 12%, and spinal in 8%. Fifty-three patients (62%) underwent gross-total resection and 28 (33%) underwent subtotal resection. Histopathological analysis revealed 62 (71%) WHO Grade I, 21 (24%) Grade II, and four (5%) Grade III meningiomas. One patient received adjuvant chemotherapy and four received radiotherapy. CONCLUSIONS: Using survival data from this unique patient cohort, the authors found that recurrence-free survival time was significantly related to WHO grade (p = 0.002), but overall survival time was not significantly linked to any of the potential prognostic factors considered in this study (p = 0.06).

Adolescent↗
PubMed2004

Epstein-Barr virus-associated smooth muscle tumor of the basal ganglia in an HIV+ child: case report and review of the literature.

We describe the clinicopathologic features of an Epstein-Barr virus (EBV)-associated smooth muscle tumor arising in the basal ganglia of a 10-year-old human immunodeficiency virus (HIV)-positive child. Only a few cases of intracranial smooth muscle tumors are reported in the literature and virtually all of these have been extra-axial, involving the dura or sinuses in HIV+ adults. Our case underscores the need to include an EBV-associated smooth muscle tumor in the differential diagnosis when evaluating intracranial mass lesions in immunodeficient children.

Basal Ganglia↗
PubMed2004

Spinal adrenal cortical adenoma with oncocytic features: report of the first intramedullary case and review of the literature.

Ectopic adrenal cortical neoplasms are extremely rare, and only a few have involved the CNS. We report the first case of an intramedullary oncocytic adrenal cortical neoplasm of the spinal cord with immunohistochemical (IMHC) confirmation. A 27-year-old man presented with progressive lower extremity weakness, spastic paraparesis, decreased reflexes, and hypoesthesia below T10. A spinal myelogram showed cauda equina blockade and obliteration of sacral nerve roots. This prompted emergent surgical intervention. A well-circumscribed, approximately 3 x 2 cm, light brown to tan, intramedullary tumor was identified at the level of the conus medullaris. Histologically, the tumor showed sheets and nests of plump, cytologically bland polygonal cells with abundant eosinophilic cytoplasm. A single mitosis, but no necrosis, was identified. By IMHC, the cells were positive for inhibin, melan-A, and synaptophysin, and negative for GFAP, EMA, cytokeratins, S-100, HMB-45, and chromogranin. Electron microscopy study performed from paraffin-embedded tissues demonstrated abundant mitochondria, and lipid vacuoles. This case confirms the occurrence of adrenal cortical neoplasms in the CNS and is the first report of an intradural, intramedullary adrenal cortical adenoma of the spinal cord, and the first to occur in a male. This tumor should be considered in the differential diagnosis of tumors of the CNS.

Adrenal Cortex Neoplasms↗
PubMed2004

Hypothalamic hamartoma secreting corticotropin-releasing hormone. Case report.

The authors describe a unique case of a 2-year-old boy with a hypothalamic hamartoma secreting corticotropin-releasing hormone (CRH). The patient presented with a history of behavioral disturbances progressing over 12 months. His neurological status was intact. Magnetic resonance imaging demonstrated a 1.8 x 1.6 x 1.2-cm isointense, nonenhancing hypothalamic lesion. Endocrinological workup revealed elevated serum CRH and adrenocorticotropic hormone levels, nonsuppression with low-dose dexamethasone, and partial suppression with high-dose dexamethasone. He underwent tumor resection via a right frontotemporal craniotomy. Pathological examination of the tissue confirmed a hypothalamic hamartoma with CRH immunostaining. Postoperatively, his hormone levels normalized and his behavioral disturbances abated. The radiographic and clinical characteristics of hypothalamic hamartomas are reviewed and therapeutic considerations discussed.

Adrenocorticotropic Hormone↗
PubMed2003

Spinal cord malignant astrocytomas. Clinicopathologic features in 36 cases.

BACKGROUND: Malignant astrocytomas of the spinal cord are uncommon neoplasms with a dismal prognosis. To the authors' knowledge, little information has been published to date regarding the prognostic impact of clinicopathologic factors. METHODS: The authors studied 36 cases to investigate the prognostic effect of the World Health Organization (WHO) tumor grade, tumor localization, cell proliferative activity, p53 expression, and therapy. RESULTS: Sixteen patients (44%) underwent biopsy alone, 11 (31%) underwent subtotal resection, and 7 (19%) underwent macroscopic total excision. For two patients, there were no data available regarding surgical treatment. Among the 36 patients (mean age, 32.4 years), there were 23 males (63%) and 13 (36%) females. Their initial biopsies showed 21 (63%) glioblastoma multiforme (GBM) cases (WHO Grade 4), 13 (36%) anaplastic astrocytomas (AA) (WHO Grade 3), and 2 (6%) astrocytomas (A) (WHO Grade 2). After initial surgery, 10 (29%) patients were treated with radiation therapy alone and 7 (19%) received radiation therapy with chemotherapy. Patterns of disease recurrence included extraneural metastases (two cases), brain metastases (five cases), local extension (one case), and diffuse spread along the neuraxis (six cases). Two A (100%) and six AA (46%) cases progressed to GBM. The overall median survival time was 33 months (range, 24-42 months) for A, 10 months (range, 1-84 months) for AA, and 10 months (range, 1-43 months) for GBM. CONCLUSIONS: Patients older than 40 years have a shorter survival period compared with younger patients. There is a high risk of central nervous system dissemination in patients with this disease.

Adolescent↗
PubMed2002

'Spindle cell oncocytoma' of the adenohypophysis: a tumor of folliculostellate cells?

We describe five primary tumors of the adenohypophysis featuring mitochondrion-rich spindle cells. The patient ages ranged from 53 to 71 years (mean 61.6 years); two were female. All presented with panhypopituitarism. Two also had visual field defect. On neuroimaging all tumors showed suprasellar extension and were indistinguishable from pituitary adenoma. None showed imaging or operative evidence of dural involvement. All were gross totally removed: four by transsphenoidal surgery and one by frontal craniotomy. Follow-up ranged from 2 to 68 months (mean 35.4 months). No recurrences were noted. The clinical workup was noncontributory in all but two patients: one (case no. 4) with an oncocytic thyroid adenoma and another (case no. 5) with squamous carcinoma of both the uterine cervix and of vocal cord. Histologically, the five tumors were composed mainly of fascicles of spindle cells with eosinophilic, granular cytoplasm. Mitoses were rare and necrosis was absent. Neoplastic cells were immunoreactive for vimentin, epithelial membrane antigen, S-100 protein, and galectin-3. Stains for pituitary hormones, synaptophysin, chromogranin, glial fibrillary acidic protein, cytokeratin CAM5.2, smooth muscle actin, CD34, and CD68 were negative. No thyroglobulin immunoreactivity was noted in the tumor of case no. 4. Ultrastructurally, the neoplastic cells contained numerous mitochondria with lamellar cristae. The neoplastic cells were linked by intermediate junctions and desmosomes. No secretory granules were noted. The histologic, immunohistochemical, and fine structural features of these tumors were unlike those of pituitary adenoma or any other primary sellar tumor. A derivation from adenohypophyseal folliculostellate cells is suggested.

Adenoma, Oxyphilic↗
PubMedDate not supplied

Subepidermal calcified nodules.

Subepidermal calcified nodules (SCNs) are uncommon, benign lesions usually presenting in childhood which occasionally involve the eyelids. Only a handful of cases have been reported in the ophthalmologic literature. We present 2 cases, one in a 7-year-old Hispanic boy, the other in a 13-year-old African American boy, with eyelid lesions which were clinically thought to be possible juvenile xanthogranuloma, but which on histopathologic examination showed the characteristic features of SCNs.

Adolescent↗