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Several carcinomas including gastric cancer have been reported to contain Epstein‐Barr virus (EBV) infection. EBV‐associated gastric cancer (EBVaGC) is classified as one of four molecular subtypes of gastric cancer by The Cancer Genome Atlas (TCGA) group with increased immune‐related signatures. Identification of EBV‐dependent pathways with significant biological roles is needed for EBVaGC. To compare the biological changes between AGS gastric epithelial cells and EBV‐infected AGS (AGS‐EBV) cells, proliferation assay, CCK‐8 assay, invasion assay, cell cycle analysis, RT‐PCR, Western blot and ELISA were performed. BI836845, a humanized insulin‐like growth factor (IGF) ligand‐neutralizing antibody, was used for IGF‐related signalling pathway inhibition. AGS‐EBV cells showed slower proliferating rate and higher sensitivity to BI836845 compared to AGS cells. Moreover, invasiveness of AGS‐EBV was increased than that of AGS, and BI836845 treatment significantly decreased the invasiveness of AGS‐EBV. Although no apoptosis was detected, entry into the S phase of the cell cycle was delayed in BI836845‐treated AGS‐EBV cells. In conclusion, AGS‐EBV cells seem to modulate their proliferation and invasion through the IGF signalling pathway. Inhibition of the IGF signalling pathway therefore could be a potential therapeutic strategy for EBVaGC.

Purpose Precision oncology approach for recurrent and metastatic head and neck squamous cell carcinoma (HNSCC) is necessary due to its dismal prognosis. We performed a genomic profile-based umbrella trial of patients with platinum-refractory HNSCC (KCSG-TRIUMPH). Here, we present an in-depth report of the the nintedanib arm (arm 3) of the current trial.Materials and Methods The TRIUMPH study was a multicenter, open-label, single-arm phase 2 trial, in which patients were assigned to treatment arms based on next-generation sequencing (NGS)–based, matching genomic profiles. Patients whose tumors harbor fibroblast growth factor receptor (FGFR) alteration were enrolled in the nintedanib arm (arm 3) as part of the TRIUMPH study. The primary endpoint was the overall response rate (ORR), and secondary endpoints included overall survival (OS), progression-free survival (PFS), safety, and biomarker analysis.Results Between October 2017 and August 2020, 207 were enrolled in the TRIUMPH study, and eight were enrolled in the nintedanib arm. ORR and disease control rate were 42.9% and 57.1%, respectively. The median PFS was 5.6 months and the median duration of response was 9.1 months. Median OS was 11.1 months. One patient maintained the partial response for 36 months. Overall, the toxicity profiles were manageable.Conclusion Single-agent nintedanib has demonstrated significant efficacy in FGFR-mutated, recurrent or metastatic HNSCC patients, with tolerable toxicity profiles. The results from the study have provided the basis for routine NGS screening and FGFR-targeted therapy. Because of the small number of patients due to slow accrual in this study, further studies with a larger cohort are warranted for statistical power.

Purpose Epigenetic dysregulation is a common characteristic of cancers, including gastric cancer (GC), and contributes to cancer development and progression. Although the efficacy of BET (an epigenetic regulator) inhibition has been demonstrated in various cancer types, predictive genetic markers of its efficacy in GC are currently lacking. Therefore, we aimed to identify markers that predict the response of BET inhibition in GC and, suggest an effective treatment regimen through combined therapy. Methods The effect of BET inhibition was evaluated using iBET-151, a small-molecule inhibitor of BET proteins, in a large panel (n = 49) of GC cell lines and xenograft mouse models. Comprehensive genetic information was used to identify cell lines sensitive to iBET-151. Flow cytometry, Western blotting, and colony-formation and migration assays were used to evaluate the effects of iBET-151 and/or paclitaxel. The synergistic effect of iBET-151 and paclitaxel was evaluated using an organoid model. ResultsWe found that iBET-151 showed a modest growth-inhibitory effect in GC cells (73%, 36/49). iBET-151 inhibited tumorigenicity in vitro and significantly promoted cell cycle arrest and apoptosis. Based on comprehensive genetic information analysis in relation to BET family expression, we found that BRD4 was highly expressed in the iBET-151-sensitive cell lines. We also identified WNT5B and IRS2 as potential biomarkers that are predictive for sensitivity to iBET-151. In GC xenograft model mice, iBET-151 significantly decreased tumor volumes and Ki-67 and BRD4 expression. Combination treatment showed that iBET-151 increased the sensitivity of GC cells to paclitaxel in approximately 70% of the cell lines (34/49) tested. iBET-151 plus paclitaxel significantly promoted cell cycle arrest and apoptosis and suppressed c-Myc, Bcl-2 and Bcl-xL expression. In GC organoids, iBET-151 and paclitaxel showed a synergistic effect. Conclusions Collectively, our data suggest that iBET-151 is a potential therapeutic agent for GC, especially in combination with paclitaxel, and that WNT5B and IRS2 may predict iBET-151 sensitivity.