BRAF V600E VARIANT IDENTIFIED AS A TARGETABLE SOMATIC VARIANT PICKED UP BY NEXT GENERATION SEQUENCING IN THYROID TISSUE SAMPLES FROM SOUTH INDIA

Abstract

Molecular targeted therapy is custom tailored treatment aiming at the molecular variations that drive the cancer growth.
BRAF (B-homologue of the Rapidly Accelerated Fibrosarcoma) V600E variant is one such variant seen in several cancers
that serves as a promising target for therapy. The aim of the present study was to evaluate the percentage of Thyroid
Cancer (TC) cases harboring BRAF V600E mutation, from patients of two tertiary care hospitals of south India to plan
specific molecular therapy irrespective of the tumor pathology. Samples were recruited into the study after the
histopathological confirmation as, Papillary TC (PTC), Follicular TC (FTC), Medullary TC (MTC) and Anaplastic TC
(ATC) cases based on the morphology. In the study, 106 different FFPE thyroid cancer samples were recruited of which
13 samples were subjected to Next Generation Sequencing using Comprehensive Onco CEPT panel. BRAF V600E
variation was analyzed using Polymerase Chain Reaction followed by Restriction Fragment Length Polymorphism. 2
samples out of 13 sequenced harbored BRAF V600E variation, which was tested on the rest of the samples. In total 38%
of the TC samples were found to harbor BRAF V600E variation located in the exon 15 implying that these could be
benefitted from the targeted therapy. It is the most common variation seen in TC and also in several other cancers. It
serves as a promising target for therapy and a better prognosis for radio-iodine refractory thyroid carcinomas. Tyrosine
Kinase inhibitors like Dabrafenib and Trametinib can be given to these patients.