title: Nuclear overexpression of bcl-2 oncoprotein during the progression of human stomach cancer.
abstract: We unexpectedly observed strong nuclear overexpression of bcl-2 protein in advanced stomach cancer. As far as we know, such expression has not yet been reported. To investigate the significance of nuclear expression of bcl-2 protein in gastric carcinoma, we immunohistochemically analyzed bcl-2 overexpression in a gastric carcinogenic sequence, including 19 tubular adenomas (TA), 20 early carcinomas (EGC), and 20 advanced carcinomas (AGC). While TA displayed a specific granular and supranuclear cytoplasmic staining pattern, adenocarcinomas showed a strong nuclear staining pattern. Nuclear staining of bcl-2 was observed in 50% of AGC, 30% of EGC, and 10% of TA; cytoplasmic staining, on the other hand, was observed in all TA, 5% of EGC, and 10% of AGC. Nuclear bcl-2 overexpression differed according to the histologic type of AGC, occurring in 67% of the diffuse type and 25% of the moderately-to-well differentiated type. In the diffuse type, nuclear bcl-2 positive AGC predominated. In metastatic lesions, the pattern of bcl-2 immunostaining was almost identical to that seen in primary tumor. These results suggest that nuclear expression of bcl-2 may be related to malignant transformation in the stomach and is frequently associated with diffuse type advanced gastric adenocarcinomas.
authors.affiliation: Department of Anatomic Pathology, Korea Cancer Center Hospital, Seoul National University College of Medicine.
authors.forename: S S
authors.initials: SS
authors.lastname: Lee
authors.forename: K J
authors.initials: KJ
authors.lastname: Cho
authors.forename: S I
authors.initials: SI
authors.lastname: Hong
authors.forename: N K
authors.initials: NK
authors.lastname: Myoung
authors.forename: J J
authors.initials: JJ
authors.lastname: Jang
mesh_terms: D000236:Adenoma / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D002277:Carcinoma / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D002467:Cell Nucleus / Q000378:metabolism*; D018450:Disease Progression; D006801:Humans; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000096:biosynthesis*; D013274:Stomach Neoplasms / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology
chemical_list: D019253:Proto-Oncogene Proteins c-bcl-2