Whole-exome sequencing identifies MST1R as a genetic susceptibility gene in nasopharyngeal carcinoma.

Multiple factors, including host genetics, environmental factors, and Epstein-Barr virus (EBV) infection, contribute to nasopharyngeal carcinoma (NPC) development. To identify genetic susceptibility genes for NPC, a whole-exome sequencing (WES) study was performed in 161 NPC cases and 895 controls of Southern Chinese descent. The gene-based burden test discovered an association between macrophage-stimulating 1 receptor (MST1R) and NPC. We identified 13 independent cases carrying the MST1R pathogenic heterozygous germ-line variants, and 53.8% of these cases were diagnosed with NPC aged at or even younger than 20 y, indicating that MST1R germline variants are relevant to disease early-age onset (EAO) (age of ≤20 y). In total, five MST1R missense variants were found in EAO cases but were rare in controls (EAO vs. control, 17.9% vs. 1.2%, P = 7.94 × 10(-12)). The validation study, including 2,160 cases and 2,433 controls, showed that the MST1R variant c.G917A:p.R306H is highly associated with NPC (odds ratio of 9.0). MST1R is predominantly expressed in the tissue-resident macrophages and is critical for innate immunity that protects organs from tissue damage and inflammation. Importantly, MST1R expression is detected in the ciliated epithelial cells in normal nasopharyngeal mucosa and plays a role in the cilia motility important for host defense. Although no somatic mutation of MST1R was identified in the sporadic NPC tumors, copy number alterations and promoter hypermethylation at MST1R were often observed. Our findings provide new insights into the pathogenesis of NPC by highlighting the involvement of the MST1R-mediated signaling pathways.

Phase II trial of capecitabine plus cisplatin as first-line therapy in patients with metastatic nasopharyngeal cancer.

BACKGROUND: Capecitabine is an oral fluoropyrimidine with single-agent activity in metastatic nasopharyngeal carcinoma (NPC). This multicenter phase II study was conducted to investigate the efficacy and safety of capecitabine plus cisplatin as a first-line treatment for metastatic NPC. METHODS: Patients with metastatic NPC received cisplatin 100 mg/m(2) day 1 plus capecitabine 1000 mg/m(2) twice daily on days 1 to 14 every 3 weeks for 6-8 cycles. The primary endpoint was overall response rate. RESULTS: Forty-four patients were enrolled; 39 patients were evaluable for efficacy. The overall response rate was 53.8% (95% confidence interval [CI], 37%-70%), including 1 complete response. Median time to tumor progression was 7.3 months (95% CI, 5.6-9.9 months) and median overall survival was 28.0 months (95% CI, 14.5 months-not reached). Common grade 3/4 adverse events were neutropenia (50%), vomiting (11%), thrombocytopenia (9%), and nausea (7%). CONCLUSIONS: Capecitabine plus cisplatin is an active first-line combination in metastatic NPC that requires a short hospital stay.