It is still uncertain if targeted therapy-based regimens in advanced gastric cancer actually produce survival benefit. To shed light on this important question, we performed a systematic review and meta-analyses on each relevant targeted-pathway. By searching literature databases and proceedings of major cancer meetings in the time-frame 2005-2014, 22 randomized clinical trials exploring targeted therapy for a total of 7022 advanced gastric cancer patients were selected and included in the final analysis. Benefit was demonstrated for antiangiogenic agents in terms of overall survival (HR 0.759; 95%CI 0.655-0.880; p < 0.001). Conversely no benefit was found for EGFR pathway (HR 1.077; 95%CI 0.847-1.370; p D 0.543). Meta-analysis of HER-2 pathway confirmed improvement in terms of survival outcome, already known for this class of drugs (HR 0.823; p D 0.004). Pooled analysis demonstrated a significant survival benefit (OS: HR 0.823; PFS: HR 0.762) with acceptable tolerability profile for targeted-based therapies as compared to conventional treatments. This finding conflicts with the outcome of most individual studies, probably due to poor trial design or patients selection. In conclusion, our findings demonstrate a significant survival benefit for targeted therapy in its whole, which can be ascribed to anti-angiogenic and anti-HER2 agents.

Myopericytoma (MPC) is a rare tumor with perivascular proliferation of pluripotent stem-cell-like pericytes. Although indolent, MPC may be locally aggressive with recurrent disease. The pathogenesis and diagnostic biomarkers of MPC are poorly understood. We discovered that 15% of benign MPCs (thyroid, skin; 3 of 20 samples) harbored BRAF(WT/V600E); 33.3% (1 of 3 samples) of BRAF(WT/V600E)-MPCs were multifocal/infiltrative/recurrent. Patient-MPC and primary MPC cells harbored BRAF(WT/V600E), were clonal and expressed pericytic-differentiation biomarkers crucial for its microenvironment. BRAF(WT/V600E)-positive thyroid MPC primary cells triggered in vitro (8.8-fold increase) and in vivo (3.6-fold increase) angiogenesis. Anti-BRAF(V600E) therapy with vemurafenib disrupted angiogenic and metabolic properties (~3-fold decrease) with down-regulation (~2.2-fold decrease) of some extracellular-matrix (ECM) factors and ECM-associated long non-coding RNA (LincRNA) expression, with no effects in BRAF(WT)-pericytes. Vemurafenib also inhibited (~3-fold decrease) cell viability in vitro and in BRAF(WT/V600E)-positive thyroid MPC patient-derived xenograft (PDX) mice (n = 5 mice per group). We established the first BRAF(WT/V600E)-dependent thyroid MPC cell culture. Our findings identify BRAF(WT/V600E) as a novel genetic aberration in MPC pathogenesis and MPC-associated biomarkers and imply that anti-BRAF(V600E) agents may be useful adjuvant therapy in BRAF(WT/V600E)-MPC patients. Patients with BRAF(WT/V600E)-MPC should be closely followed because of the risk for multifocality/recurrence.