MAPK3 and esophageal cancer: The CXCL1/CXCR2 axis has been shown to participate in the regulation of ERK1/2 phosphorylation in esophageal cancer, which is responsible for the transcription of the EGR-1 gene, the crosstalk of among CXCL1/CXCR2 axis, ERK1/2 and EGR-1 result in a rapid increase in tumor cell proliferation [36].