SOX2 and small cell lung carcinoma: According to citation analysis and sigma value detection, the class literature was Leora, Horn, 2018, New Engl J Med (3) titled “First-line atezolizumab plus chemotherapy in extensive-stage small-cell lung cancer” in “the New England Journal of Medicine” and Rudin, Charles M., Nat Genet, 2012 (30) titled “Comprehensive genomic analysis identifies SOX2 as a frequently amplified gene in small-cell lung cancer” in “Nature Genetics”.