Research Projects

Background Gliomas are the most common primary, intra-axial neoplasms of the CNS. The latest 2021 World Health Organization classification of tumors of the Central Nervous System, has introduced the concept of “histomolecular” that is, combining the histopathological and molecular features to classify and grade gliomas. IDH-mutation is the most common genetic alteration is adult-type diffuse gliomas, astrocytomas and oligodendrogliomas and is a marker of good prognosis. CDKN2A gene deletion is a marker of poor prognosis in diffuse astrocytomas. Confocal Raman spectroscopy is a high-resolution imaging technique widely used for the characterization of specimens by their chemical composition. Raman histology is a useful surgical adjunct for identifying tumor infiltration in vivo. There is a paucity of studies on the utility of Raman spectroscopy for identification of IDH gene mutation status and other histomolecular subtypes of gliomas. Rationale To the best of our knowledge, there are as yet, no studies from the Indian subcontinent regarding the utility of Raman spectroscopy in the histomolecular subtyping of adult-type diffuse gliomas. This project, to evaluate the biofingerprint of the histomolecular glioma subtypes by Raman spectroscopy can be considered as the first step towards the incorporation of Raman spectroscopy in the intra-operative workflow with definite translational relevance. Objectives Major objectives: 1) Identification of Raman spectroscopic features of adult-type diffuse astrocytomas and oligodendrogliomas in comparison with normal cerebral cortical tissue from temporal lobe 2) Characterization and comparison of Raman spectroscopic features of IDH-mutant astrocytomas (CNS WHO grades 3 and 4) and IDH-wildtype glioblastomas 3) Characterization and comparison of Raman spectroscopic features in blood (serum) and tumor tissue of glioma patients Minor objectives: 1) Differentiating between CNS WHO grade 3 and grade 4 IDH-mutant astrocytomas by Raman spectroscopy 2) Identification of Raman spectroscopic features of IDH-mutant astrocytomas with and without CDKN2A gene deletion Methods 1) Confocal Raman spectroscopy 2) DNA extraction 3) Sanger sequencing 4) Fluorescence in situ hybridization (FISH) 5) Immunohistochemistry Expected outcome 1) Identification of the differences in Raman spectroscopic biofingerprint of adult-type diffuse gliomas in comparison with normal cerebral cortex. 2) Identification of the differences in Raman spectroscopic biofingerprint between IDH-mutant and IDH-wildtype glioblastomas 3) Identification of the differences in Raman spectroscopic biofingerprint between IDH-mutant astrocytomas CNS WHO grade 3 and grade 4 4) Detection of biochemical alterations in peripheral blood from glioma patients may lead to identification of novel biomarkers 5) Identification of the biochemical composition of gliomas may contribute towards better understanding of tumor biology