Low frequency of BRAF and KRAS mutations in Chinese patients with low-grade serous carcinoma of the ovary

Abstract

BackgroundMounting evidence has shown that KRAS and BRAF are somatic mutations associated with low grade serous carcinoma (LGSC) of the ovary. However, the frequency of KRAS or BRAF mutation was variable in literatures, with a frequency of 16–54% for KRAS mutation and 2–33% for BRAF mutation. Meanwhile, the prognostic significance of KRAS or BRAF mutation remains controversial.MethodsCodons 12 and 13 of exon 2 of KRAS gene and exon 15 of BRAF gene were analyzed using direct Sanger sequencing in 32 cases of LGSC of the ovary. The associations between KRAS or BRAF mutation and clinicopathological characteristics, overall survival (OS) and disease-free survival (DFS) were statistically analyzed.ResultsKRAS mutation was observed in nine cases (9/32, 28%) and BRAF mutation in two cases (2/32, 6%). KRAS and BRAF mutations were mutually exclusive. Neither KRAS nor BRAF mutation was statistically associated with OS or DFS in our cohort, although there was a favorable prognostic trend in patients with KRAS G12D mutation than those with KRAS G12 V mutation or wild-type KRAS for OS.ConclusionsThe present study indicated a low frequency of BRAF or KRAS mutation in Chinese patients with LGSC of the ovary, and neither KRAS nor BRAF mutation is a prognostic factor.

BRAFV600E mutations and immunohistochemical expression of VE1 protein in low‐grade serous neoplasms of the ovary

“…Patients with BRAF -mutated SBTs have been shown to present at earlier stages (37). However, no significant differences were found in overall survival or disease-free survival among BRAF -mutated and non-mutated SBTs or LGSCs in some studies (11, 37).…”

“…In our study, V600E BRAF V600E mutations were present in 48% (25/52) of SBTs and 5% (1/22) of all LGSCs. BRAF mutations have been described in up to 48% of SBTs (6–11). Some studies have reported BRAF mutations in 19-33% of LGSCs (6, 35).…”

“…KRAS and BRAF mutations are usually mutually exclusive in these tumours, with reported mutation frequencies of up to 54% for KRAS and up to 48% for BRAF . BRAF mutations have been reported in 23-48% of SBTs but in only 0-6% of LGSCs (6–11). BRAF encodes a protein from the RAF family of serine/threonine protein kinases, involved in regulating the mitogen-activated protein kinase (MAPK)/extracellular signal regulated kinase (ERK) cell signaling pathway.…”

COX-2/C-MET/KRAS status-based prognostic nomogram for colorectal cancer: A multicenter cohort study

“…Cycling conditions were as described previously. [18] After identification by agarose gel electrophoresis, the PCR products were purified with the DNA Clean/Extraction Kit (GeneMark), then submitted to direct sequencing on an ABI 3730xl genetic analyzer (Invitrogen Life Technologies, Carlsbad, CA, USA), and detailed steps were consistent with those reported earlier. [19] The resulting reads were aligned using Chromas software, and all mutations were confirmed in both the sense and anti-sense directions.…”

Prioritizing and characterizing functionally relevant genes across human tissues

“…PUS1, whose deficiency affects muscle morphology in mice (17), has a z-score of -0.78 in muscle but a FUGUE score of 0.94. KRAS, mutations in which cause ovarian carcinoma (18), has a z-score of -0.12 in ovary and FUGUE score of 0.82. TGF-beta functions in gonadal development (19).…”