Recent Advances in Liquid Biopsy of Brain Cancers

Abstract

Brain cancers are among the top causes of death worldwide. Although, the survival rates vary widely depending on the type of the tumor, early diagnosis could generally benefit in better prognosis outcomes of the brain cancer patients. Conventionally, neuroimaging and biopsy are the most widely used approaches in diagnosis, subtyping, and prognosis monitoring of brain cancers, while emerging liquid biopsy assays using peripheral blood or cerebrospinal fluid have demonstrated many favorable characteristics in this task, especially due to their minimally invasive and easiness in sampling nature. Here, we review the recent studies in the liquid biopsy of brain cancers. We discuss the methodologies and performances of various assays on diagnosis, tumor subtyping, relapse prediction as well as prognosis monitoring in brain cancers, which approaches have made a big step toward clinical benefits of brain cancer patients.

Beyond blood: Advancing the frontiers of liquid biopsy in oncology and personalized medicine

“…The low biomarker concentration requires highly sensitive methods for isolation. 19 Pleural effusions, rich in nucleic acids and proteins, are essential for diagnosing thoracic malignancies. Distinguishing malignant from benign effusions often involves density gradient centrifugation and immunoaffinity methods.…”

Advances in nano-based materials for glioblastoma multiforme diagnosis: A mini-review

“…Different approaches are employed to synthesize these HNPs: 1) top-down, a physical method where bulk material is used to form the nanostructure; and 2) bottomup, a more accessible, eco-friendly process that can control the physicochemical properties (e.g., shape, size, surface composition), once NPs are constructed from molecules and/ or atoms. Accordingly, HNPs can perform bioimaging analysis of the internalization kinetics process, endocytic pathways, and intracellular tracking of live brain cancer cells (Carvalho et al, 2020;An et al, 2021;Lee et al, 2021). Self-assembled organic−inorganic hybrids are the building blocks that can create hybrid nanosystems.…”

“…Due to limitations in acquiring blood fluid under ideal conditions, CSF has been evaluated as it is near the brain tissues and presents a higher concentration of biomarkers than plasma. Recent studies have indicated that ultrasound applied with LB increases the concentration of markers, stimulating deep tissue penetration into the tumor noninvasively (Liu et al, 2019;Liang et al, 2020;An et al, 2021).…”

Immunohistochemistry Detection of Histone H3 K27M Mutation in Human Glioma Tissue

“…Alternatively, investigations into liquid biopsy for circulating tumor DNA in plasma, serum, or cerebrospinal fluid are underway, as this method would not require invasive surgery; however, this indirect method is still in development. [14][15][16][17][18] IHC is performed using formalin-fixed paraffin-embedded (FFPE) tissue; in contrast to NGS, IHC requires less tissue, can be conducted more quickly, is less expensive, and is more readily available. 19 Available H3 K27M-specific antibodies are capable of detecting H3.1 or 3.3 K27M mutations and are agnostic to which of several genes can encode for such alteration.…”

“…Furthermore, next-generation sequencing (NGS) is time-consuming, expensive, requires specialized laboratory equipment that may not be available in community institutions, and often does not sequence for all histone H3-encoding genes. Alternatively, investigations into liquid biopsy for circulating tumor DNA in plasma, serum, or cerebrospinal fluid are underway, as this method would not require invasive surgery; however, this indirect method is still in development 14–18 …”