Opposite roles of FOXA1 and NKX2-1 in lung cancer progression.

Gene copy number profiles of primary lung tumors were screened for high-level amplifications. We detected 22 high-level amplifications in various loci, including 14q13. This locus is known to harbor the adenocarcinoma (AC) lineage-specific target gene NKX2-1, which is not expressed in squamous cell carcinoma (SCC). As the 14q amplification was also found in SCC, we investigated whether or not FOXA1 might be the corresponding target gene for SCC. Focusing on these two target genes, we assessed gene amplifications and protein expression of NKX2-1 and FOXA1 in primary lung tumors (n = 554) and brain metastases (n = 68). Primary AC (n = 194) showed positive protein expression of NKX2-1 in 58.2% of the samples compared with 4.2% of primary SCC samples (n = 212). Positive staining for FOXA1 was seen in 34.7% of the SCC samples, which was comparable with 39.6% in the AC samples. For brain metastases, FOXA1 expression was slightly higher in the SCC samples (55.6%) compared with the non-matched primary SCC tumor samples (43.4%), whereas NKX2-1 expression was comparable in both primary tumors and brain metastases. Positive FOXA1 and NKX2-1 expression was associated with a gain or amplification in 34.6% and 28.6% of cases, respectively. The expression of NKX2-1 was associated with early stage and grade among the AC cases. In contrast, FOXA1 expression in SCC was associated with distant metastases as well as an unfavorable survival rate (P = 0.039). These results suggest that both FOXA1 and NKX2-1 may act as lineage-specific target genes within the 14q amplicon with opposite functions in lung cancer.

Prognostic implications of netrin-1 expression and its receptors in patients with adenocarcinoma of the pancreas.

BACKGROUND: To assess the interaction between the expression of netrin-1 or of its receptors to the prognosis of ductal adenocarcinoma of the pancreas. METHODS: In 82 patients with resectable pancreatic adenocarcinoma who underwent curative operation, the expression patterns of netrin-1, deleted in colorectal carcinomas (DCC), UNC5H3, and neogenin were determined by immunohistochemical staining. Kaplan-Meier analysis was performed to assess the prognostic relevance of the examined expression patterns. RESULTS: Median follow-up was 15 +/- 19.9 months (range, 4-108 months). Patients suffering from tumors with no or little expression of netrin-1 (n = 67) had a median recurrence-free survival of 10 months (95% CI, 7-13 months), while a middle to strong expression (n = 15) was associated with a significantly worse median recurrence-free survival of only four months (95% CI, three to five months, p = 0.0165). Overall and recurrence-free survival showed no significant differences between the different expression patterns of DCC, UNC5H3 or neogenin. Netrin-1 expression had significant impact (p = 0.001) on overall survival of patients suffering from poorly differentiated tumors. Stratification according to the nodal status revealed significant influence (p = 0.007) of UNC5H3 expression on the overall survival of patients with pN1 status. CONCLUSION: Expression of netrin-1 has significant impact on time to tumor relapse in adenocarcinoma of the pancreas. Netrin-1 expression is associated with worse outcome in poorly differentiated pancreatic adenocarcinomas. Risk-stratification according to the UNC5H3 receptor expression pattern shows that node positive patients (pN1) with no to little UNC5H3 expression carry a significantly worse prognosis than those with middle to strong UNC5H3 expression.