title: [Growth inhibition of combined pathway inhibitors on KRAS mutated non-small cell lung cancer cell line].
abstract: OBJECTIVE
  To investigate the effect of the selective PI3K inhibitor and MEK inhibitor on KRAS and PTEN co-mutated non-small cell lung cancer cell line NCI-H157 and the relevant mechanisms.
  
  
  METHODS
  NCI-H157 was cultured routinely and treated with different concentrations of the two inhibitors. Cell proliferation was detected by MTT cell cycle assay. Based on the MTT results the cells were divided into four groups: the control group, PI3K inhibitor group (GDC-0941, 0.5 and 5.0 µmol/L), combination group I (0.5 µmol/L AZD6244 + 0.5 µmol/L GDC-0941) and combination group II (5.0 µmol/L AZD6244 + 5.0 µmol/L GDC-0941). Colony formation assay was performed to detect colony formation efficiency. The cell cycle and apoptosis were analyzed by flow cytometry. The expression of protein related to apoptosis was tested with Western blot.
  
  
  RESULTS
  Cell growth was inhibited by the two inhibitors. Combination groups led to stronger cell proliferation inhibition: combination group Ishowed synergistic effect of their actions and combination group II showed an additive effect; in both groups, there were decreased colony number [(77.2 ± 1.54)/well vs (61.50 ± 2.12)/well, P < 0.01] and [(51.00 ± 4.00)/ well vs (22.50 ± 3.53)/well, P < 0.01]; and enhanced apoptotic ratios [(18.30 ± 0.82)% vs (21.32 ± 0.56)%, P < 0.01] and [(27.14 ± 1.58)% vs (42.45 ± 4.42)%, P < 0.01]. In addition, compared to the PI3K inhibitor alone group, the NCI-H157 cells in the combination groups showed increased G0/G1 phase and decreased S phase (P < 0.01). Western blotting showed that the combination groups demonstrated significantly decreased expression of cyclin D1 and cyclin B1, increased p21 and cleaved PARP and decreased bcl-2/bax ratio, compared to the PI3K inhibitor only group.
  
  
  CONCLUSIONS
  The combined inhibition of PI3K (AZD6244) and MEK (GDC-0941) has synergistic effects on the proliferation of NCI-H157 cells, but such effects appear to be in a dose-dependent manner.
authors.affiliation: Department of Pathology, Peking Union Medical College, Beijing, China.
authors.forename: Zhan-wen
authors.initials: ZW
authors.lastname: Li
authors.forename: Zhen-li
authors.initials: ZL
authors.lastname: Yang
authors.forename: Hai-liang
authors.initials: HL
authors.lastname: Feng
authors.forename: Xiao-cui
authors.initials: XC
authors.lastname: Bian
authors.forename: Yan-yan
authors.initials: YY
authors.lastname: Liu
authors.forename: Yu-qin
authors.initials: YQ
authors.lastname: Liu
mesh_terms: D017209:Apoptosis / Q000187:drug effects; D001562:Benzimidazoles / Q000008:administration & dosage / Q000494:pharmacology*; D002289:Carcinoma, Non-Small-Cell Lung / Q000235:genetics / Q000473:pathology; D002453:Cell Cycle / Q000187:drug effects; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects*; D056744:Cyclin B1 / Q000378:metabolism; D019938:Cyclin D1 / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004357:Drug Synergism; D006801:Humans; D007191:Indazoles / Q000008:administration & dosage / Q000494:pharmacology*; D008175:Lung Neoplasms / Q000235:genetics / Q000473:pathology; D020929:Mitogen-Activated Protein Kinase Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D009154:Mutation; D051059:PTEN Phosphohydrolase / Q000235:genetics; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D000081082:Phosphoinositide-3 Kinase Inhibitors; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D016283:Proto-Oncogene Proteins p21(ras) / Q000378:metabolism; D015398:Signal Transduction; D013449:Sulfonamides / Q000008:administration & dosage / Q000494:pharmacology*; D051028:bcl-2-Associated X Protein / Q000378:metabolism; D018631:ras Proteins / Q000235:genetics*
chemical_list: D001562:Benzimidazoles; D056744:Cyclin B1; D019938:Cyclin D1; D007191:Indazoles; D020929:Mitogen-Activated Protein Kinase Kinases; D051059:PTEN Phosphohydrolase; D019869:Phosphatidylinositol 3-Kinases; D000081082:Phosphoinositide-3 Kinase Inhibitors; D011065:Poly(ADP-ribose) Polymerases; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D016283:Proto-Oncogene Proteins p21(ras); D013449:Sulfonamides; D051028:bcl-2-Associated X Protein; D018631:ras Proteins; C532162:2-(1H-indazol-4-yl)-6-(4-methanesulfonylpiperazin-1-ylmethyl)-4-morpholin-4-ylthieno(3,2-d)pyrimidine; C517975:AZD 6244; C534699:CCNB1 protein, human; C530104:CCND1 protein, human; C117307:KRAS protein, human