BACKGROUND/AIMS: Serrated adenomas of the colon show mixed characteristics of both hyperplastic and adenomatous polyps. Serrated adenomas are known to progress via the serrated pathway than the adenoma-carcinoma pathway. The aim of this study was to evaluate the characteristics of traditional serrated adenomas compared to hyperplastic polyps and tubular adenomas by using immunohistochemical staining for p53, Bcl-2, and Ki-67. METHODS: Age, sex, location, size and the immunoexpression of p53, Bcl-2, and Ki-67 were retrospectively analyzed in 20 traditional serrated adenomas, 20 hyperplastic polyps, and 20 tubular adenomas from January 2007 to December 2012 at The Catholic University of Korea, Yeouido St. Mary's Hospital. RESULTS: There was no difference in Bcl-2 and p53 expression between traditional serrated adenomas and hyperplastic polyps. Ki-67 Expression of traditional serrated adenomas was higher than that of hyperplastic polyps (p=0.001). Ki-67 and p53 expression was similar between traditional serrated and tubular adenomas. Bcl-2 expression of traditional serrated adenomas was lower than that of tubular adenomas (p=0.001). Regarding the expression of p53, Bcl-2, and Ki-67 in traditional serrated adenomas, there were no statistical differences among age, sex, location, and size. CONCLUSIONS: Our study suggested that Ki-67 may be helpful in distinguishing traditional serrated adenomas from hyperplastic polyps, and p53 expression may be ineffective in distinguishing between traditional serrated and tubular adenomas. From Bcl-2 expression, it is suggested that the tumorigenesis of traditional serrated adenomas is lower than that of tubular adenomas.
Adenoma/genetics/metabolism/*physiopathology ; Aged ; Colonic Polyps/physiopathology ; Colorectal Neoplasms/genetics/metabolism/*physiopathology ; Female ; *Gene Expression Regulation, Neoplastic ; Humans ; Immunohistochemistry ; Ki-67 Antigen/*genetics/metabolism ; Male ; Middle Aged ; Proto-Oncogene Proteins c-bcl-2/*genetics/metabolism ; Retrospective Studies ; Tumor Suppressor Protein p53/*genetics/metabolism

BACKGROUND/AIMS: Serrated adenomas of the colon show mixed characteristics of both hyperplastic and adenomatous polyps. Serrated adenomas are known to progress via the serrated pathway than the adenoma-carcinoma pathway. The aim of this study was to evaluate the characteristics of traditional serrated adenomas compared to hyperplastic polyps and tubular adenomas by using immunohistochemical staining for p53, Bcl-2, and Ki-67. METHODS: Age, sex, location, size and the immunoexpression of p53, Bcl-2, and Ki-67 were retrospectively analyzed in 20 traditional serrated adenomas, 20 hyperplastic polyps, and 20 tubular adenomas from January 2007 to December 2012 at The Catholic University of Korea, Yeouido St. Mary's Hospital. RESULTS: There was no difference in Bcl-2 and p53 expression between traditional serrated adenomas and hyperplastic polyps. Ki-67 Expression of traditional serrated adenomas was higher than that of hyperplastic polyps (p=0.001). Ki-67 and p53 expression was similar between traditional serrated and tubular adenomas. Bcl-2 expression of traditional serrated adenomas was lower than that of tubular adenomas (p=0.001). Regarding the expression of p53, Bcl-2, and Ki-67 in traditional serrated adenomas, there were no statistical differences among age, sex, location, and size. CONCLUSIONS: Our study suggested that Ki-67 may be helpful in distinguishing traditional serrated adenomas from hyperplastic polyps, and p53 expression may be ineffective in distinguishing between traditional serrated and tubular adenomas. From Bcl-2 expression, it is suggested that the tumorigenesis of traditional serrated adenomas is lower than that of tubular adenomas.
Adenoma/genetics/metabolism/*physiopathology ; Aged ; Colonic Polyps/physiopathology ; Colorectal Neoplasms/genetics/metabolism/*physiopathology ; Female ; *Gene Expression Regulation, Neoplastic ; Humans ; Immunohistochemistry ; Ki-67 Antigen/*genetics/metabolism ; Male ; Middle Aged ; Proto-Oncogene Proteins c-bcl-2/*genetics/metabolism ; Retrospective Studies ; Tumor Suppressor Protein p53/*genetics/metabolism

Several molecular and genetic changes have been found in pituitary adenomas. We looked for correlations between these changes and the degree of invasiveness of the tumors. The invasiveness of 11 pituitary adenomas was graded by Hardy classification. We examined the retinoblastoma gene (RB1.20 on chromosome 13q) and the region around the MEN1 locus (chromosome 11q13.1-5) for loss of heterozygosity. Also examined are p53 mutations using single strain conformation polymorphism, p53 protein overexpression using immuno cytochemistry, homozygous deletions of p15 and p16 by polymerase chain reaction, and cellular proliferative activity using MIB-1 antibody. Six tumors (54.5%) had an LOH at either RB1.20 or the MEN1 locus. LOHs were found more frequently in Grade 4 and stage E tumors (72% and 67%) than in Grade 3 and stage D tumors (25% and 40%). However, no mutation or overexpression of p53 was found. No homozygous deletions of p15 or p16 were identified. The cell proliferative index ranged from 0 to 3%. LOH at 11q13 and 13q may be valuable in predicting the invasiveness of pituitary adenomas.
Adenoma/*genetics/*pathology/physiopathology/radiography ; Adult ; Aged ; Aged, 80 and over ; Cell Cycle Proteins/genetics ; Cell Transformation, Neoplastic ; Chromosomes, Human, Pair 11 ; Chromosomes, Human, Pair 13 ; Female ; *Genes, Retinoblastoma ; Genes, Tumor Suppressor ; Genes, p53 ; Human ; Loss of Heterozygosity ; Male ; Middle Age ; Mutation ; Neoplasm Invasiveness ; Neoplasm Proteins/*genetics ; Pituitary Neoplasms/*genetics/*pathology/physiopathology/radiography ; Polymorphism, Single-Stranded Conformational ; Protein p16/genetics ; Protein p53/genetics/metabolism