CXCR4 and small cell lung carcinoma: CXCR4-targeted therapies in SCLC show promise in preclinical studies; a study by Otani et al. showed a significant decrease in the number and size of lung metastases in mice with CXCR4-expressing SCLC treated with the peptide-based inhibitor of CXCR4, TF14016 [54].