Current and future biomarkers in gastric cancer

Gastric cancer is the fourth most common worldwide cause of cancer-related death. Early gastric cancer has no associated symptoms, for this reason, patients come to the attention of the clinicians only in advanced stages. This paper aims to give a global view on the biomarkers for gastric cancer and the therapy in use. We discuss VEGF family, HER family, E-cadherin, PD-L1, and PD-L2, FGFR, mTOR. Finally, we considered emerging biomarkers as MET, microsatellite instability, and microRNA variations. Furthermore, we have analyzed in depth the chemotherapeutic and adjuvant therapies used in the clinic nowadays, comparing the overall and progression-free survival between them. Identifying and validating diagnostic, prognostic, predictive, and pharmacodynamic biomarkers will be mandatory to the huge impact on patients' outcomes and for improving the efficiency of the drug development process.