title: MDM2 gene amplification: a new independent factor of adverse prognosis in non-small cell lung cancer (NSCLC).
abstract: The prognostic impact of MDM2 amplification in non-small cell lung cancer (NSCLC) remains unknown. In this study, we investigated the occurrence of MDM2 amplification in surgically treated NSCLC patients. Molecular data were correlated with clinicopathological factors and evaluated for their prognostic value. The study group included 116 NSCLC patients who underwent pulmonary resection between 1996 and 1999. MDM2 amplification was assessed by real-time PCR using hybridization probe format on a LightCycler (Roche). The calculated ratio was a MDM2 value normalized to the amplification of the housekeeping gene phenylalaninhydroxylase (PAH). Survival curves were drawn according to the Kaplan-Meier method and compared with the use of the log-rank test. Multivariate analysis was based on Cox regression analysis. MDM2 amplification was found in 24 patients (21%). There was no relationship between MDM2 amplification and clinicopathological factors, such as sex, age and stage of disease, pT, pN, histology and tumor differentiation. Median disease-free survival (DFS) in patients with and without MDM2 amplification was 3 and 31 months, and 5-year DFS 24 and 33%, respectively (log-rank, P = 0.02). Likewise, median overall survival (OS) in patients with and without MDM2 amplification was 9 and 33 months, respectively, and 5-year OS 24 and 39%, respectively (log-rank, P = 0.01). The strong prognostic relevance of MDM2 amplification for both DFS and OS was confirmed in multivariate analysis (P < 0.01 for both comparisons). Our results suggest that MDM2 gene amplification analysis provides additional prognostic information in surgically treated NSCLC patients.
authors.affiliation: Department of Internal Medicine, Endocrinology and Haemostatic Disorders, Medical University of Gdańsk, Gdańsk, Poland.
authors.forename: Dorota
authors.initials: D
authors.lastname: Dworakowska
authors.forename: Ewa
authors.initials: E
authors.lastname: Jassem
authors.forename: Jacek
authors.initials: J
authors.lastname: Jassem
authors.forename: Brigitte
authors.initials: B
authors.lastname: Peters
authors.forename: Rafał
authors.initials: R
authors.lastname: Dziadziuszko
authors.forename: Maciej
authors.initials: M
authors.lastname: Zylicz
authors.forename: Joanna
authors.initials: J
authors.lastname: Jakóbkiewicz-Banecka
authors.forename: Grazyna
authors.initials: G
authors.lastname: Kobierska-Gulida
authors.forename: Amelia
authors.initials: A
authors.lastname: Szymanowska
authors.forename: Jan
authors.initials: J
authors.lastname: Skokowski
authors.forename: Albert
authors.initials: A
authors.lastname: Roessner
authors.forename: Regine
authors.initials: R
authors.lastname: Schneider-Stock
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D018287:Carcinoma, Large Cell / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D002289:Carcinoma, Non-Small-Cell Lung / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D002294:Carcinoma, Squamous Cell / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D005260:Female; D005784:Gene Amplification; D006801:Humans; D007124:Immunoenzyme Techniques; D008175:Lung Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009687:Nuclear Proteins / Q000235:genetics*; D011379:Prognosis; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D051736:Proto-Oncogene Proteins c-mdm2; D012333:RNA, Messenger / Q000235:genetics; D012334:RNA, Neoplasm / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015996:Survival Rate
chemical_list: D009687:Nuclear Proteins; D011518:Proto-Oncogene Proteins; D012333:RNA, Messenger; D012334:RNA, Neoplasm; C497206:MDM2 protein, human; D051736:Proto-Oncogene Proteins c-mdm2