Singh KP, Dhruva A, Flowers E, et al. - Researchers here examined two independent samples of oncology patients who did and did not experience chemotherapy-induced nausea (CIN) for differentially expressed genes and perturbed pathways linked with the gut-brain axis (GBA). Study questionnaires were completed by oncology patients (n = 735) in the week prior to their second or third cycle of chemotherapy. The Memorial Symptom Assessment Scale was used to assess the CIN occurrence. Two independent samples were assessed in gene expression analyses using RNA-sequencing (sample 1, n = 357) and microarray (sample 2, n = 352) methodologies. In sample 1 and sample 2, CIN was reported in 63.6% and 48.9% of the patients, respectively, indicating persistent CIN as a significant clinical problem. This work is identified to be the first recognizing novel GBA-related pathways associated with the occurrence of CIN. Across the two samples, differential expression of 703 genes was observed and they identified 37 pathways that were perturbed between the two CIN groups. Observations revealed nine perturbed pathways involved in mechanisms correlated with alterations in the GBA (ie, mucosal inflammation, disruption of gut microbiome).