A total of 59 PTCs from both groups were evaluated for BRAF mutation on tumor tissue and on ctDNA from plasma samples by real-time polymerase chain reaction (PCR) and digital PCR.
We identified 14 hits whose silencing was able to significantly reduce the viability and the proliferation of TPC1 cells; most of them were active also in BRAF-mutant BCPAP (papillary thyroid cancer) and 8505C (anaplastic thyroid cancer) and in RAS-mutant CAL62 (anaplastic thyroid cancer) cells.
In this work, we analyzed the expression of PDE5 in a series of human papillary thyroid carcinomas (PTCs) presenting or not BRAFV600E mutation and classified according to ATA risk criteria.
It was significantly associated with extrathyroidal and vascular invasion of FVPTC and FTC and, remarkably, a 50%-60% rate of multifocality and recurrence of BRAF mutation-positive PTC (P = 0.01 and 0.02, respectively).
Thirty-five pediatric PTCs were screened for the most prevalent fusions (RET/PTC1, RET/PTC2, RET/PTC3, ETV6-NTRK3, and AGK-BRAF) and point mutations (BRAF<sup>V600E</sup> and NRAS<sup>Q61</sup>) described in sporadic pediatric PTCs.
These preliminary results may provide evidence for the involvement of the common genetic variants scattered throughout the BRAF oncogene in the prediction of PTC onset and progression.
We found that numerical changes in BRAF copy number were rare in papillary thyroid carcinomas, while they occurred in 16-45% of follicular tumors of conventional and oncocytic (Hürthle cell) types.
BRAF(V600E) status of FNAB cell blocks from 55 patients with PTC was analyzed by immunohistochemistry (IHC) with the new BRAF(V600E) antibody (clone VE1) and by Sanger sequencing (SaS).
In conclusion, BRAF fusions are rare driver alterations in a wide variety of malignant neoplasms, but enriched in Spitzoid melanoma, pilocytic astrocytomas, pancreatic acinar and papillary thyroid cancers.
Activating point mutation of the BRAF gene resulting in V600E (previously designated as V599E) is a common event in thyroid papillary carcinoma, being found in approx 40% of this tumor.