The Notch signaling pathway is deregulated in numerous solid types of cancer including non-small cell lung cancer (NSCLC). However, the profile of Notch ligand expression remains unclear. Therefore, the present study aimed to determine the profile of Notch ligands in NSCLC patients and to investigate whether quantitative assessment of Notch ligand expression may have prognostic significance in NSCLC patients. The study was performed in 61 pairs of tumor and matched unaffected lung tissue specimens obtained from patients with various stages of NSCLC, which were analyzed by reverse transcription-polymerase chain reaction. The marked expression levels of certain analyzed genes were detected in NSCLC samples and in noncancerous lung samples. Of the five Notch ligands, jagged 1 (Jag1), jagged 2, delta-like protein 1 and delta-like protein 4 were expressed in the majority of tissues, but their expression levels were reduced in NSCLC when compared with noncancerous lung tissue (P<0.001). Delta-like protein 3 expression was consistently low and was observed only in 21/61 tumor tissue samples. Taken together, Notch ligands are expressed in NSCLC. However, the expression level is reduced when compared to noncancerous tissue. Furthermore, the present study revealed that quantitative assessment of Jag1 expression in NSCLC may improve prognostication of patient survival.
Keywords: Notch 1; delta-like protein 1; delta-like protein 3; delta-like protein 4; hairy and enhancer of split-1; jagged 1; jagged 2; non-small cell lung cancer; notch; notch ligands.