Identifying specific Notch1 target proteins in lung carcinoma cells.

Background The Notch signaling pathway has different roles in many human neoplasms, being either tumor-promoting or anti-proliferative. In addition, Notch signaling in carcinogenesis can be tissue dependent. The aim of the current study is to elucidate the relation between Notch1 protein expression in lung cancer cells and the following Notch related proteins: Hes1, c-Myc, Jagged1 and Jagged2. Methods Notch1 and its related proteins were detected in human lung cancer cell lines and in 54 surgically resected different lung carcinoma tissues. Then, we used small interfering RNA (siRNA) technology, to down-regulate the expression of Notch1 in H69AR and SBC3 small cell lung carcinoma (SCLC) cells. Also, we transfected venus Notch1 intracellular domain (v.NICD) plasmid into human SCLC lines; H69. Results The expression of Hes1, c-Myc and Jagged2 is affected by Notch1 in SCLC. Conclusion There is a strong association between the expression of Notch1 protein and the expression of Hes1, c-Myc and Jagged2 proteins, which could aid in better understanding tumorigenesis in SCLC.