Calcium electroporation of esophageal cancer induces gene expression changes: a sub-study of a phase I clinical trial

Purpose In this study, we aim to investigate gene expression changes in tumor samples obtained from patients with esophageal cancer treated with calcium electroporation. Previously, local treatment with calcium electroporation has been shown to induce gene expression alterations, potentially contributing to a more tumor-hostile microenvironment. Methods In this sub-study of a phase I clinical trial, we included five patients with esophageal cancer treated with calcium electroporation. We compared cancer-associated gene expression patterns in tumor samples before and after treatment. Furthermore, we used linear support vector regression to predict the cellular composition of tumor samples. Results Using differential expression analysis, we identified the downregulation of CXCL14 and upregulation of CCL21 , ANGPTL4 , and CRABP2 genes. We also found a decreased predicted proportion of dendritic cells while the proportion of neutrophils was increased. Conclusion This study provides evidence that calcium electroporation for esophageal cancer induces local transcriptional changes and possibly alters the cellular composition of the tumor microenvironment. The results are explorative, larger studies are needed to confirm and further correlate our findings with clinical outcomes.