PROJECT SUMMARY/ABSTRACT
Despite advances in surgical techniques and clinical regimens, malignant gliomas usually progress or recur after
treatment. Currently, visual inspection of imaging data is the mainstay to monitor glioma progression; however,
this approach may not be accurate or refined enough to monitor treatment response or evolving prognostic
subtypes. Imaging data has limited ability to distinguish 1) gliomas from other tumors (e.g., primary central
nervous system lymphoma), 2) progression from pseudoprogression (pseudoPD) resulting from therapy-induced
necrosis, or 3) minimal or remnant tumoral burden. Recently, we and others found that potential drivers of glioma
progression are mediated by gene mutation and epigenetic abnormalities. Generally, cancer molecular
signatures are identifiable in tumoral tissue; however, several groups have reported that tumor specific
signatures using both genetics and DNA methylation can be captured by non- or minimally-invasive approach
such as liquid biopsy (LB) using biospecimens such as blood and cerebrospinal fluid. To address this knowledge
gap in the role of LB to monitor glioma progression/recurrence, we aim to establish a novel approach to detect
postoperative malignant glioma using DNA methylation of blood-derived cell-free DNA (cfDNA) markers with the
ultimate goal to fine-tune surveillance and treatment in real time. With available DNA methylation data extracted
from serum/plasma cfDNA at initial diagnosis, we will develop a non-invasive Glioma-score that is associated
with prognostically relevant subtypes of glioma (e.g., G-CIMP-high vs -low), gliomas harboring unique and
druggable genetic alterations (FGFR3-TACC3 [F3-T3]) and gliomas developing in patients with
Neurofibromatosis type 1 (NF1-glioma) (Aim 1). From available cohorts spanning longitudinal specimens
accrued for more than a decade, we will profile the epigenome of paired primary and recurrent sets (e.g., first,
second /or third recurrence), and develop a Glioma recurrence (GliomaR)-score associated with recurrence, and
response to therapy (Aim 2). Based on our defined scores, we will classify patients into defined prognostic
groups (e.g., good and poor outcome) and risk to recur as a more aggressive subtype upon recurrence
subgroups. This will assess the accuracy of LB to monitor postoperative progression of different molecular
subtypes of glioma throughout an individual’s disease. We will utilize the quantitative and semi-quantitative
imaging features routinely used in the diagnosis and monitoring of glioma to correlate the epigenomic markers
of the LB Glioma-score with well established glioma imaging standards and tailor the LB score towards the
resolution of the current limitations of imaging data for human glioma (e.g., pseudoPD and radiation necrosis)
(Aim 3). Our study will be the first to investigate glioma whole-epigenome LB markers to detect aggressive
gliomas at initial diagnosis and during tumor progression. Accurate diagnosis through a simple blood test will
allow clinicians to detect the evolution of the disease in real-time, thus identifying high-risk patients who may
benefit from more aggressive therapy at an earlier point when intervention could be more effective.