Integrated analysis of whole genome and transcriptome sequencing in a young patient with gastric cancer provides insights for precision therapy

Gastric cancer is a leading cause of cancer-associated deaths worldwide and is considered to be an age-related disease. In younger patients, gastric cancer is biologically more aggressive, and prognosis is worse compared with that in elderly patients. In the present case report, the whole genome and transcriptome was sequenced in a 26-year-old patient with gastric cancer who presented with gastric cancer-related symptoms and was admitted to the First Affiliated Anhui Medical Hospital (Hefei, China) in December 2016. In total, 9 germline and 4 somatic mutations were identified in the patient, and there were more deleterious sites in the germline mutated genes. Genes with somatic mutations, such as MUC2, MUC4, SLC8A2, and with structural variations, including CCND3, FGFR2 and FGFR3, were found to be differentially expressed. Cancer-associated pathways, such as the ‘calcium signaling pathway’, ‘cGMP-PKG signaling pathway’ and ‘transcriptional mis-regulation’ were also enriched at both the genomic and transcriptomic levels. The genes found to have germline (SFRP4), somatic (MUC2, MUC4, SLC8A2) mutations, or structural variations (CCND3, FGFR2 and FGFR3) were differentially expressed in the patient and could be promising precision therapy targets.