title: Gene expression analysis of early and advanced gastric cancers.
abstract: Gastric carcinoma is one of the major causes of cancer mortality worldwide. Early detection results in excellent prognosis for patients with early cancer (EGC), whereas the prognosis of advanced cancer (AGC) patients remains poor. It is not clear whether EGC and AGC are molecularly distinct, and whether they represent progressive stages of the same tumor or different entities ab initio. Gene expression profiles of EGC and AGC were determined by Affymetrix technology and quantitative polymerase chain reaction. Representative regulated genes were further analysed by in situ hybridization (ISH) on tissue microarrays. Expression analysis allowed the identification of a signature that differentiates AGC from EGC. In addition, comparison with normal gastric mucosa indicated that the majority of alterations associated with EGC are retained in AGC, and that further expression changes mark the transition from EGC to AGC. Finally, ISH analysis showed that representative genes, differentially expressed in the invasive areas of EGC and AGC, are not differentially expressed in the non-invasive areas of the same tumors. Our data are more directly compatible with a progression model of gastric carcinogenesis, whereby EGC and AGC may represent different molecular stages of the same tumor. Finally, the identification of an AGC-specific signature might help devising novel therapeutic strategies for advanced gastric cancer.
authors.affiliation: IFOM Fondazione Istituto FIRC di Oncologia Molecolare, Milan, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Vecchi
authors.forename: P
authors.initials: P
authors.lastname: Nuciforo
authors.forename: S
authors.initials: S
authors.lastname: Romagnoli
authors.forename: S
authors.initials: S
authors.lastname: Confalonieri
authors.forename: C
authors.initials: C
authors.lastname: Pellegrini
authors.forename: G
authors.initials: G
authors.lastname: Serio
authors.forename: M
authors.initials: M
authors.lastname: Quarto
authors.forename: M
authors.initials: M
authors.lastname: Capra
authors.forename: G C
authors.initials: GC
authors.lastname: Roviaro
authors.forename: E
authors.initials: E
authors.lastname: Contessini Avesani
authors.forename: C
authors.initials: C
authors.lastname: Corsi
authors.forename: G
authors.initials: G
authors.lastname: Coggi
authors.forename: P P
authors.initials: PP
authors.lastname: Di Fiore
authors.forename: S
authors.initials: S
authors.lastname: Bosari
mesh_terms: D014408:Biomarkers, Tumor / Q000096:biosynthesis* / Q000235:genetics*; D002454:Cell Differentiation / Q000235:genetics; D049109:Cell Proliferation; D018450:Disease Progression; D005500:Follow-Up Studies; D020869:Gene Expression Profiling; D006801:Humans; D020411:Oligonucleotide Array Sequence Analysis; D012720:Severity of Illness Index; D013274:Stomach Neoplasms / Q000145:classification / Q000235:genetics* / Q000378:metabolism / Q000473:pathology*
chemical_list: D014408:Biomarkers, Tumor