NOTCH1 and small cell lung carcinoma: Research found that SCLC cells showed a significant growth arrest with active Notch1/2, attributing to activation of p21 and arrest of G1 cell cycle.6 Notch knockdown may lead to an increase in cell proliferation, validating the antitumor effect in SCLC cells.80 Furthermore, the Notch pathway had an identifying role in regulating neuroendocrine gene expression in SCLC by specimens’ genomic analysis.