Oncogenic GNAQ and GNA11 mutations in uveal melanoma in Chinese

To examine whether GNAQ and GNA11 somatic mutations previously identified in uveal melanomas of Caucasians are associated with uveal melanomas in Chinese patients.

Uveal melanomas treated by primary enucleation in Chinese patients underwent a mutation analysis of GNAQ and GNA11 with sequencing of exon 5 and exon 4.

The study included 50 patients with uveal melanoma and with a mean age of 47.6±13.0 years. During the follow-up of at least 3 years, 20 (40%) patients developed extraocular metastases. The frequencies of GNAQ and GNA11 somatic mutations in uveal melanoma were 18% (9/50) and 20% (10/50), respectively. The mutations occurred exclusively in codon 209 of exon 5. No mutations were detected in exon 4. Mutations affecting codon 209 in GNAQ were c.626A>C(Q209P) (78%) and c.626A>T(Q209L) (22%). Mutations affecting codon 209 in GNA11 were exclusively c.626A>T(Q209L) (100%). In none of the tumors, mutations of BRAF and NRAS were detected. GNAQ/11 mutations were marginally (P = 0.045) associated with optic disc involvement. In Kaplan-Meier analysis, metastasis-free survival was not significantly (P = 0.94) associated with GNAQ/11 mutations.

Mutations of GNAQ and GNA11 can be found in Chinese patients as in Caucasian patients with uveal melanoma, with a higher frequency reported for Caucasian patients.