SMARCB1 Gene Mutation Predisposes to Earlier Development of Glioblastoma: A Case Report of Familial GBM

Abstract

Glioblastoma (GBM) is the most aggressive adult brain tumor. While GBM typically occurs sporadically, familial GBM can be associated with certain hereditary disorders and isolated familial GBMs in the absence of syndrome are rare. Relevant hereditary factors have remained elusive in these cases. Understanding specific genetic abnormality may potentially lead to better treatment strategies in these patients. Here, we analyzed GBM tissue from our patient and 2 afflicted family members, with next generation sequencing to better understand the genetic alterations associated with this disease development. DNA was extracted and sequenced and the data were then analyzed. Results revealed 2 common mutations in afflicted family members; PDGFRA and HRAS. In addition, both siblings showed a mutation of the SMARCB1 gene. The sister of our patient exhibited a homozygous mutation, while our patient had heterozygous mutation of this gene in the tumor tissue. This result suggests that mutation of SMARCB1, either alone or in the presence of PDGFRA and HRAS mutations, is associated with earlier onset GBM.