Ramucirumab for metastatic gastric or gastroesophageal junction cancer: results and implications of the REGARD trial

Co-targeting CD47 and VEGF elicited potent anti-tumor effects in gastric cancer

BACKGROUND

CD47, serving as an intrinsic immune checkpoint, has demonstrated efficacy as an anti-tumor target in hematologic malignancies. Nevertheless, the clinical relevance of CD47 in gastric cancer and its potential as a therapeutic target remains unclear.

METHODS

The expression of CD47 in clinical gastric cancer tissues was assessed using immunohistochemistry and Western blot. Patient-derived cells were obtained from gastric cancer tissues and co-cultured with macrophages derived from human peripheral blood mononuclear cells. Flow cytometry analyses were employed to evaluate the rate of phagocytosis. Humanized patient-derived xenografts (Hu-PDXs) models were established to assess the efficacy of anti-CD47 immunotherapy or the combination of anti-CD47 and anti-VEGF therapy in treating gastric cancer. The infiltrated immune cells in the xenograft were analyzed by immunohistochemistry.

RESULTS

In this study, we have substantiated the high expression of CD47 in gastric cancer tissues, establishing a strong association with unfavorable prognosis. Through the utilization of SIRPα-Fc to target CD47, we have effectively enhanced macrophage phagocytosis of PDCs in vitro and impeded the growth of Hu-PDXs. It is noteworthy that anti-CD47 immunotherapy has been observed to sustain tumor angiogenic vasculature, with a positive correlation between the expression of VEGF and CD47 in gastric cancer. Furthermore, the successful implementation of anti-angiogenic treatment has further augmented the anti-tumor efficacy of anti-CD47 therapy. In addition, the potent suppression of tumor growth, prevention of cancer recurrence after surgery, and significant prolongation of overall survival in Hu-PDX models can be achieved through the simultaneous targeting of CD47 and VEGF using the bispecific fusion protein SIRPα-VEGFR1 or by combining the two single-targeted agents.

CONCLUSIONS

Our preclinical studies collectively offer substantiation that CD47 holds promise as a prospective target for gastric cancer, while also highlighting the potential of anti-angiogenic therapy to enhance tumor responsiveness to anti-CD47 immunotherapy.

BPTF Drives Gastric Cancer Resistance to EGFR Inhibitor by Epigenetically Regulating the C-MYC/PLCG1/Perk Axis

Erlotinib, an EGFR tyrosine kinase inhibitor, is used for treating patients with cancer exhibiting EGFR overexpression or mutation. However, the response rate of erlotinib is low among patients with gastric cancer (GC). The findings of this study illustrated that the overexpression of bromodomain PHD finger transcription factor (BPTF) is partially responsible for erlotinib resistance in GC, and the combination of the BPTF inhibitor AU-1 with erlotinib synergistically inhibited tumor growth both in vivo and in vitro. AU-1 inhibited the epigenetic function of BPTF and decreased the transcriptional activity of c-MYC on PLCG1 by attenuating chromosome accessibility of the PLCG1 promoter region, thus decreasing the expression of p-PLCG1 and p-Erk and eventually improving the sensitivity of GC cells to erlotinib. In patient-derived xenograft (PDX) models, AU-1 monotherapy exhibited remarkable tumor-inhibiting activity and is synergistic anti-tumor effects when combined with erlotinib. Altogether, the findings illustrate that BPTF affects the responsiveness of GC to erlotinib by epigenetically regulating the c-MYC/PLCG1/pErk axis, and the combination of BPTF inhibitors and erlotinib is a viable therapeutic approach for GC.

Association of FLG mutation with tumor mutation load and clinical outcomes in patients with gastric cancer

Background: Stomach adenocarcinoma (STAD) is one of the most frequently diagnosed cancers in the world with a poor prognosis due to genetic heterogeneity. The present study aimed to explore potential prognostic predictors and therapeutic targets that can be used for STAD treatment.

Methods: We collected relevant data of STAD patients from the Cancer Genome Atlas (TCGA), including somatic mutation, transcriptome, and survival data. We performed a series of analyses such as tumor mutational burden (TMB), immune infiltration, and copy number variation (CNV) analysis to evaluate the potential mechanism of filaggrin (FLG) mutation in gastric cancer. Gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, and gene set enrichment analysis (GSEA) were performed for annotation of differentially expressed genes (DEGs). The STRING online database was used to construct the protein–protein interaction (PPI) and ceRNA network and hub genes were identified. Univariate and multivariate Cox regression analyses were used to determine the effect of selected DEGs on tumor prognosis.

Results: The FLG-mutant group (FLG-MT) showed a higher mutation load and immunogenicity in gastric cancer. GO and KEGG analyses identified and ranked unique biologic processes and immune-related pathway maps that correlated with the FLG-mutant target. GSEA analysis showed that several tumorigenesis and metastasis-related pathways were indeed enriched in FLG-mutant tumor tissue. Both cell cycle–related pathways and the DNA damage and repair associated pathways were also enriched in the FLG-MT group. The FLG mutations resulted in increased gastric cancer sensitivity to 24 chemotherapeutic drugs. The ceRNA network was established using Cytoscape and the PPI network was established in the STRING database. The results of the prognostic information further demonstrated that the OS and DFS were significantly higher in FLG mutation carriers, and the FLG gene mutation might be a protective factor.

Conclusion: The multiple molecular mechanisms of the FLG gene in STAD are worthy of further investigation and may reveal novel therapeutic targets and biomarkers for STAD treatment.

Clinical management patterns of advanced and metastatic gastro-oesophageal carcinoma after fluoropyrimidine/platinum treatment in France, Germany, Spain and the United Kingdom

OBJECTIVE

To describe treatment patterns and resource utilisation in France, Germany, Spain and the United Kingdom (UK) in patients with unresectable locally advanced and/or metastatic gastro-oesophageal adenocarcinoma (GEA), who failed first-line fluoropyrimidine/platinum treatment.

METHODS

Treating physicians completed a web-based chart review (2013-2015). Eligible patients were ≥ 18 years old; had unresectable locally advanced and/or metastatic gastric adenocarcinoma including the gastro-oesophageal junction; received first-line fluoropyrimidine/platinum-based therapy; and had ≥ 3 months of follow-up after first-line discontinuation. Data were summarised descriptively for each country.

RESULTS

There were n = 201 patients in France, n = 202 in Germany, n = 208 in Spain and n = 200 in the UK whose charts were reviewed. Percentages of patients receiving second-line therapy were 55% (France), 48% (Germany), 54% (Spain) and 29% (UK). At the start of second-line therapy, most patients had an ECOG performance status of 1 (range 0-3). Second-line therapy was primarily monotherapy, but agents used varied within and across countries. Supportive care use and resource utilisation were frequent whether receiving additional therapy or not; >60% patients had clinic visits unrelated to chemotherapy administration, and > 30% has ≥ 1 hospital admission.

CONCLUSIONS

For the time of study, established GEA treatment guidelines were generally followed. However, therapies varied widely in the second-line setting.

Risk of gastrointestinal perforation in cancer patients receiving ramucirumab: a meta-analysis of randomized controlled trials

PURPOSE

Although existing evidence from clinical trials has demonstrated manifestation of gastrointestinal perforation with the use of ramucirumab, overall risks have yet to be reported. Therefore, we performed a meta-analysis of published randomized controlled trials (RCTs) to get a better understanding of the overall incidence and risk of gastrointestinal perforation associated with ramucirumab.

METHODS

The PubMed and Web of Science databases as well as abstracts presented at American Society of Clinical Oncology conferences were searched to identify relevant studies published up to 01 May 2015. Eligible studies included randomized trials of ramucirumab either alone or in combination with another agent compared with the control arm without ramucirumab and that reported gastrointestinal perforation event. Overall incidence, relative risk (RR) and 95% confidence intervals (CI) were computed using fixed- or random-effects models depending on the heterogeneity of the included studies.

RESULTS

A total of 4579 patients with a variety of solid malignancies from six RCTs were included in our meta-analysis. The incidence of gastrointestinal perforation related to ramucirumab was 1.5% (95% CI 1.1-2.1%) with a mortality of 29.8% (95% CI 14.9-50.7%). The RR of gastrointestinal perforation associated with ramucirumab was 2.56 (95% CI 1.29-5.09; P  =  0.007).

CONCLUSIONS

Treatment with the ramucirumab is associated with a significant increase in risk of gastrointestinal perforation in cancer patients.

Ramucirumab: A Review in Advanced Gastric Cancer

Ramucirumab (Cyramza(®)), an intravenously administered, monoclonal antibody against vascular endothelial growth factor receptor-2, is approved in the USA, EU and Japan (either as a single agent or in combination with paclitaxel) as second-line treatment in adults with advanced gastric or gastro-oesophageal junction adenocarcinoma. In two phase III trials (REGARD and RAINBOW) in this indication, overall survival and progression-free survival were significantly prolonged with ramucirumab 8 mg/kg every 2 weeks compared with placebo, and with ramucirumab 8 mg/kg every 2 weeks plus weekly paclitaxel compared with placebo plus paclitaxel. Ramucirumab had a generally acceptable tolerability profile in phase III trials; hypertension was the most common non-haematological adverse event of grade 3 or higher with ramucirumab (either alone or with paclitaxel). As the first antiangiogenic agent to provide significant survival benefit in patients with advanced gastric cancer, ramucirumab is a valuable option in the second-line treatment of advanced gastric or gastro-oesophageal junction adenocarcinoma.

Incidence and risk of hypertension with ramucirumab in cancer patients: a meta-analysis of published studies

BACKGROUND AND OBJECTIVE

Ramucirumab is a novel antiangiogenic agent approved as second-line therapy for patients with advanced stomach cancer and gastroesophageal junction adenocarcinoma. Although existing evidence from clinical trials has demonstrated hypertension is one of the major adverse events of this agent, overall risks have yet to be reported.

METHODS

We carried out a meta-analysis of published studies to determine the overall incidence and relative risk (RR) of hypertension associated with ramucirumab. Statistical analyses were conducted to calculate the summary incidence, RRs, and 95 % confidence intervals (CIs) by using a random effects model.

RESULTS

Eleven studies with a total of 3,851 patients with multiple cancers were included. The overall incidence of all-grade hypertension was 20.0 % (95 % CI 15.0-26.0) with 8.6 % (95 % CI 6.3-11.7) being high-grade hypertension. The risk of developing hypertension was greater in ramucirumab-treated patients (RR for all grades 2.77, 95 % CI 1.94-3.94, p < 0.001, RR for high-grade 3.58, 95 % CI 2.45-5.23, p < 0.001).

CONCLUSIONS

Administration of ramucirumab to patients with cancer is associated with increased risk of hypertension.

Genomic assays for Epstein-Barr virus-positive gastric adenocarcinoma

A small set of gastric adenocarcinomas (9%) harbor Epstein–Barr virus (EBV) DNA within malignant cells, and the virus is not an innocent bystander but rather is intimately linked to pathogenesis and tumor maintenance. Evidence comes from unique genomic features of host DNA, mRNA, microRNA and CpG methylation profiles as revealed by recent comprehensive genomic analysis by The Cancer Genome Atlas Network. Their data show that gastric cancer is not one disease but rather comprises four major classes: EBV-positive, microsatellite instability (MSI), genomically stable and chromosome instability. The EBV-positive class has even more marked CpG methylation than does the MSI class, and viral cancers have a unique pattern of methylation linked to the downregulation of CDKN2A (p16) but not MLH1. EBV-positive cancers often have mutated PIK3CA and ARID1A and an amplified 9p24.1 locus linked to overexpression of JAK2, CD274 (PD-L1) and PDCD1LG2 (PD-L2). Multiple noncoding viral RNAs are highly expressed. Patients who fail standard therapy may qualify for enrollment in clinical trials targeting cancer-related human gene pathways or promoting destruction of infected cells through lytic induction of EBV genes. Genomic tests such as the GastroGenus Gastric Cancer Classifier are available to identify actionable variants in formalin-fixed cancer tissue of affected patients.