Regarding the influence of catecholamines on therapy for severe gastric cancer, it has been observed that the stimulation of gastric cancer cells with catecholamines in vitro increases trastuzumab resistance by not only activating STAT3 and extracellular signal-regulated kinases (ERKs) but also by upregulating mucin 4 (MUC4) expression [29]. The gene discussed is MUC4; the disease is gastric cancer.