title: The growth inhibitory effect of lapatinib, a dual inhibitor of EGFR and HER2 tyrosine kinase, in gastric cancer cell lines.
abstract: HER2 overexpression is observed in 5-25% of gastric cancers. Lapatinib is a dual inhibitor of the epidermal growth factor receptor and HER2 tyrosine kinase. We examined the antitumor effect of lapatinib in gastric cancer cell lines. Lapatinib induced selective and potent growth inhibition in two HER2-amplified gastric cancer cell lines (SNU-216 and NCI-N87). Lapatinib inhibited the phosphorylation of HER2, EGFR and downstream signaling proteins, resulting in G1 arrest in both cell lines with down-regulation of cMyc and induction of p27kip1. Lapatinib also induced apoptosis in NCI-N87 which has high HER2 amplification ratio. Lapatinib combined with 5-fluorouracil, cisplatin, oxaliplatin or paclitaxel showed an additive or synergistic effect. These results provide a rationale for the future clinical trials of lapatinib combined with cytotoxic drugs in the treatment of HER2-positive gastric cancer.
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, 28 Yongon-dong, Chongno-gu, Seoul 110-744, Republic of Korea.
authors.forename: Jin Won
authors.initials: JW
authors.lastname: Kim
authors.forename: Hwang-Phill
authors.initials: HP
authors.lastname: Kim
authors.forename: Seock-Ah
authors.initials: SA
authors.lastname: Im
authors.forename: Soyeong
authors.initials: S
authors.lastname: Kang
authors.forename: Hyung Seok
authors.initials: HS
authors.lastname: Hur
authors.forename: Young-Kwang
authors.initials: YK
authors.lastname: Yoon
authors.forename: Do-Youn
authors.initials: DY
authors.lastname: Oh
authors.forename: Jee Hyun
authors.initials: JH
authors.lastname: Kim
authors.forename: Dong Soon
authors.initials: DS
authors.lastname: Lee
authors.forename: Tae-You
authors.initials: TY
authors.lastname: Kim
authors.forename: Yung-Jue
authors.initials: YJ
authors.lastname: Bang
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D015153:Blotting, Western; D002455:Cell Division / Q000187:drug effects*; D045744:Cell Line, Tumor; D066246:ErbB Receptors / Q000037:antagonists & inhibitors*; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D000077341:Lapatinib; D010766:Phosphorylation; D047428:Protein Kinase Inhibitors / Q000494:pharmacology*; D011799:Quinazolines / Q000494:pharmacology*; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000037:antagonists & inhibitors*
chemical_list: D000970:Antineoplastic Agents; D066246:ErbB Receptors; D000077341:Lapatinib; D047428:Protein Kinase Inhibitors; D011799:Quinazolines; D018719:Erb-b2 Receptor Tyrosine Kinases