cyclin-d1 and beta-lapachone

Objective To investigate the effect and molecular mechanism of β-lapachone combined with NVP-BEZ235 on the proliferation and migration of BGC-823 human gastric cancer cells. Methods BGC-823 cells were randomly divided into four groups: control group, 1 μmol/L β-lapachone group, 50 nmol/L NVP-BEZ235 group and 1 μmol/L β-lapachone combined with 50 nmol/L NVP-BEZ235 group. The proliferation of cells was determined using the MTT assay and colony formation assay. The expression levels of proliferation-related proteins phosphorylated AKT (p-AKT), phosphorylated NF-κB (p-NF-κB), phosphorylated extracellular signal-regulated kinase (p-ERK) and cyclin D1 were detected by Western blotting. The migration of cells was measured by wound healing assay and Transwell

Topics: Antineoplastic Agents; Apoptosis; beta Catenin; Cell Line, Tumor; Cell Movement; Cell Proliferation; Cyclin D1; Humans; Imidazoles; Naphthoquinones; NF-kappa B; Phosphatidylinositol 3-Kinases; Phosphorylation; Proto-Oncogene Proteins c-akt; Quinolines; Signal Transduction; Stomach Neoplasms; TOR Serine-Threonine Kinases

Anticancer effects of beta-lapachone (beta-lap) are due to generation of ROS and metabolic catastrophes as a result of NAD(P)H:quinone oxidoreductase (NQO1)-mediated futile cycling between the oxidized and reduced forms of beta-lap. It has been shown that NQO1 is also essential for the TNF-induced activation of NF-kappaB and that beta-lap suppresses the TNF-induced NF-kappaB activation. We investigated whether or not NQO1 is involved and beta-lap suppresses the radiation-induced NF-kappaB activation using A549 human lung cancer cells and NQO1-knock down A549 cells (shNQO1 A549 cells). Irradiation with 4 Gy markedly increased the DNA binding activity of NF-kappaB in A549 cells, but not in the shNQO1 A549 cells, thus demonstrating that NQO1 plays a pivotal role in irradiation-induced NF-kappaB activation. Treatment with 10 micronM beta-lap for 4 h almost completely abrogated the radiation-induced increase in NF-kappaB activation and the transcription of NF-kappaB target genes such as bcl2, gadd45beta and cyclinD1. Moreover, beta-lap markedly suppressed the activation of IkappaB kinase gamma (IKKgamma) and the subsequent phosphorylation of IkappaBalpha, thereby inhibiting NF-kappaB activation. It is concluded that beta-lap suppresses the radiation-induced activation of NF-kappaB by interrupting the involvement of NQO1 in the activation of NF-kappaB, thereby inhibiting the transcription of survival signals. The radiosensitization caused by beta-lap may, in part, be attributed to beta-lap-induced suppression of NF-kappaB activation.

Topics: Antigens, Differentiation; Cell Line, Tumor; Cell Survival; Cyclin D1; Humans; I-kappa B Kinase; Lung Neoplasms; NAD(P)H Dehydrogenase (Quinone); Naphthoquinones; NF-kappa B; Proto-Oncogene Proteins c-bcl-2; Radiation-Sensitizing Agents; Radiation, Ionizing