Mutations of GNAQ, GNA11, SF3B1, EIF1AX, PLCB4 and CYSLTR in Uveal Melanoma in Chinese Patients.

BACKGROUND: The purpose of this study is to determine the mutation frequencies of key driver genes in uveal melanoma (UM) in Chinese patients and to detect associations between metastasis and the mutation of these genes.

METHOD: A total of 85 patients with UM were enrolled in this study, including 18 patients with metastasis and 67 without metastasis. Sanger sequencing covering the mutational hotspot regions of the G protein subunit alpha Q (GNAQ), GNA11, splicing factor 3B subunit 1 (SF3B1), X-linked eukaryotic translation initiation factor 1A (EIF1AX), phospholipase C beta 4 (PLCB4) and cysteinyl leukotriene receptor 2 (CYSLTR2) genes was used to analyse the mutations in Chinese patients.

RESULTS: The frequencies of GNAQ and GNA11 mutations in UM were 45% (38/85) and 35% (30/85) respectively. The frequencies of SF3B1 and EIF1AX mutations were 37% (31/85) and 9% (8/85) respectively. Only 2 mutations were detected in exon 4 of GNAQ, and no mutations were detected in exon 4 of GNA11. A novel mutation, c.627G>T (Q209H) in GNA11 was found. The detected mutations affecting SF3B1 were c.1873C>T (R625C), c.1874G>A (R625H) and c.1874G>T (R625L). The association between the mutations in SF3B1 and low risk of metastasis was statistically significant (OR 0.17, 95% CI 0.035-0.819). The mutations affecting EIF1AX were -23G>A (5'-UTR), c.5C>G (P2R), c.23G>A (G8Q), c.25G>C (G9A) and c.38_39GC>CT (R13P). No mutations were found in the PLCB4 and CYSLTR2 genes. Unfortunately, information on BRCA1-associated protein 1 could not be obtained.

CONCLUSIONS: These data indicate that mutations in the PLCB4 and CYSLTR2 genes are rare in Chinese UM patients. The mutations in GNAQ, GNA11 and EIF1AX were not associated with metastasis, whereas SF3B1 mutations were correlated with low risk of metastasis and demonstrated a protective effect in UM patients in China.