['The B cell leukemia 11A (BCL11A) gene was identified as a proto-oncogene in hematopoietic cell malignancies and breast cancer. Alternative RNA splicing generates three main transcripts designated as Extra-long (XL; 5.9 kb/125 kD), Long (L; 3.8 kb/100 kD) and Short (S; 2.4 kb/35 kD). Our previous study results demonstrated that BCL11A expression levels were specifically upregulated in non-small cell lung cancer (NSCLC) tissues, especially in squamous cell carcinoma (SCC) and large cell carcinoma (LCC).', 'In this study, we detected the BCL11A protein isoforms with immunohistochemistry (IHC) method in NSCLC with in a cohort (n=40) of BCL11A overexpression NSCLC patients. All 40 cases were BCL11A overexpression including 27 SCCs, 8 LCCs and 5 adenocarcinomas (ACs). Relationship between BCL11A isoforms and the clinicopathological parameters were also analyzed.', 'Compare to the BCL11A-L and S isoforms, the BCL11A-XL isoform was specifically expressed in SCC and LCC (P=0.006). There were 19 (19/40, 47.5%) cases positive for BCL11A-XL expression, SCC accounted for 63.2% (12/19) and LCC accounted for 36.8% (7/19). The survival analysis indicated that BCL11A-XL expression was an independent prognostic factor for disease-free survival (DFS) [hazards ratio (HR) 0.246; 95% confidence interval (CI), 0.065-0.939, P=0.040] but not for overall survival (OS) in patients with SCC and LCC.'] Does the BCL11A-XL expression predict relapse in squamous cell carcinoma and large cell carcinoma?