In this study, we found a dramatic decrease in SPDEF expression after ERKi treatment, and also established the negative regulation of Slug by SPDEF in NSCLC cells, further underlining the importance of SPDEF in regulating Slug and Slug-mediated EMT, and supporting the concept that SPDEF can be considered a therapeutic target 56. The gene discussed is SNAI2; the disease is non-small cell lung carcinoma.