Consensus framework for conducting phase I/II clinical trials for children, adolescents, and young adults with pediatric low-grade glioma: Guidelines established by the International Pediatric Low-Grade Glioma Coalition Clinical Trial Working Group

Basic mechanism of mobilizing cell movement during invasion of glioblastoma and target selection of targeted therapy

BACKGROUND

Glioblastoma (GBM), also known as glioblastoma multiforme, is a rapidly growing and highly invasive malignant tumor. Due to the inability to clearly distinguish between glioblastoma and normal tissue, surgery cannot achieve safe resection, often leading to poor patient prognosis and inevitable tumor recurrence. According to previous studies, GBM invasion is related to intercellular adhesion, matrix degradation, extracellular matrix and its related adhesion molecules, as well as the molecular matrix of protein hydrolases in the microenvironment of GBM cells and stromal cells.

AIM OF REVIEW

The aim is to enhance our understanding of the molecular mechanisms underlying GBM invasion and to advance research on targeted therapies for inhibiting GBM invasion.

KEY SCIENTIFIC CONCEPTS OF REVIEW

This article describes the protein hydrolases that may affect GBM cell invasion, changes in the cytoskeleton during motility, and the regulatory mechanisms of intracellular signaling pathways in GBM invasion. In addition, we also explored the possibility of targeted therapy against invasion related molecules in GBM.

A Phase 2 PBTC Study of Selumetinib for Recurrent/Progressive Pediatric Low-Grade Glioma: Strata 2, 5, and 6 with Long-term Outcomes on Strata 1, 3, and 4

BACKGROUND

PBTC-029B was a phase 2 trial evaluating efficacy of selumetinib in children with recurrent/progressive low-grade glioma. We report results of strata 2, 5, and 6 with updated survivals for strata 1, 3, and 4.

METHODS

Stratum 2 included recurrent/progressive pilocytic astrocytoma (PA) not associated with neurofibromatosis type-1 (NF1) that screened negative for the BRAF-KIAA1549 fusion and BRAFV600E mutation. Stratum 5 enrolled non-PA that screened positive for one of the BRAF aberrations. Stratum 6 enrolled children who consented to tissue screening, but there was an assay failure. For long-term survivals, stratum 1 included non-NF1 PA positive for one of the BRAF aberrations; stratum 3 included NF1-associated pLGG; and stratum 4 included non-NF1 optic pathway/hypothalamic tumors.

RESULTS

Stratum 2: among 14 evaluable patients, there was 1 partial response (PR), 7 stable disease (SD) and 6 progressive disease (PD); overall response rate (ORR) was 7.1%. Two-year progression-free survival (PFS)/overall survival (OS) were 57.1%/100%, respectively. Stratum 5: among 23 evaluable patients, there was 1 complete response (CR), 4 PR, 12 SD, and 6 PD; ORR was 21.7%. Two-year PFS/OS were 74.8%/100%, respectively. Stratum 6: among 26 evaluable patients, there were 7 PR, 14 SD, and 5 PD; ORR was 26.9%. Two-year PFS/OS were 72.0%/100%, respectively. The median follow-up for patients on strata 1, 3, and 4 without events are 60.4, 60.4, and 58.1 months, and 5-year PFS/OS were 30.8%/88.9%, 54.2%/100%, and 51.0%/100%, respectively.

CONCLUSIONS

Selumetinib provided stability and responses across many pLGG subgroups, and some patients achieved prolonged disease control without additional therapy.

Paediatric low-grade glioma: the role of classical pathology in integrated diagnostic practice

Low-grade gliomas are a cause of severe and often life-long disability in children. Pathology plays a key role in their management by establishing the diagnosis, excluding malignant alternatives, predicting outcomes and identifying targetable genetic alterations. Molecular diagnosis has reshaped the terrain of pathology, raising the question of what part traditional histology plays. In this review, we consider the classification and pathological diagnosis of low-grade gliomas and glioneuronal tumours in children by traditional histopathology enhanced by the opportunities afforded by access to comprehensive genetic and epigenetic characterisation.