OBJECTIVETo investigate methylation status of Wif-1 and β-catenin expression in colorectal serrated lesions.

METHODSVarious colorectal lesions were collected including 52 cases of hyperplastic polyps, 41 cases of sessile serrated adenoma, 23 cases of traditional serrated adenoma, 24 cases of colorectal cancer and 24 cases of normal mucosa. All specimens were subject to immunohistochemical staining of β-catenin.SYBR Green PCR analysis of Wif-1 promoter methylation was performed in 29 cases of hyperplastic polyps, 29 cases of sessile serrated adenoma, 19 cases of traditional serrated adenoma, 14 cases of colorectal cancer and 16 cases of normal mucosa.

RESULTSAbnormal expression rates of β-catenin in normal mucosa, hyperplastic polyps, sessile serrated adenoma, traditional serrated adenoma and colorectal cancer were 12.5% (3/24), 59.6% (31/52), 63.4% (26/41), 73.9% (17/23) and 100.0% (24/24), respectively. The corresponding methylation rates of Wif-1 promoter were 2/16, 10/29 (34.5%), 16/29 (55.2%), 15/19 and 13/14 (P < 0.05), respectively. Abnormal β-catenin expression was positively correlated with Wif-1 promoter methylation in traditional serrated adenomas (r = 0.536, P < 0.05).

CONCLUSIONSAbnormal β-catenin expression and methylation rate of Wif-1 promoter are significantly higher in colorectal serrated lesions. Methylation of Wif-1 promoter may be related to the abnormal expression of β-catenin through activation of Wnt/β-catenin signaling pathway, which may contribute to the development of colorectal serrated lesions.

Adaptor Proteins, Signal Transducing ; genetics ; metabolism ; Adenoma ; genetics ; metabolism ; pathology ; Carcinoma ; genetics ; metabolism ; pathology ; Colorectal Neoplasms ; genetics ; metabolism ; pathology ; DNA Methylation ; Humans ; Hyperplasia ; Immunohistochemistry ; Intestinal Mucosa ; metabolism ; Intestinal Polyps ; pathology ; Repressor Proteins ; genetics ; metabolism ; Wnt Signaling Pathway ; beta Catenin ; metabolism

OBJECTIVETo investigate the expression differences of minichromosome maintenance 2 (MCM2) mRNA and protein among colon adenocarcinoma, colon adenoma and normal mucosa, and among different clinicopathological types of adenomas.

METHODSFifty specimens, including 33 colonic adenomas, 12 colonic adenocarcinomas and 5 normal colonic mucosa were selected. Each specimen was divided into two parts, one for immunohistochemistry and the other for real-time RT-PCR. Expression differences of MCM2 mRNA among the colonic adenocarcinoma, adenoma and normal colonic mucosa were evaluated by REST-XL software.

RESULTSThe expression of MCM2 was observed in the basal third to half of the colonic crypts in normal mucosa, while throughout the epithelium in the colonic adenocarcinomas and adenomas. However, the expression of MCM2 mRNA in the adenocarcinomas was significantly higher than that in the adenomas(P=0.001). The MCM2 mRNA expression was elevated in the adenoma with villous type, in the conditions of high-grade dysplasia, larger size, sessile morphology and in patients of older ages, but the difference was not significant by REST-XL (P>0.05).

CONCLUSIONThe difference of MCM2 expression between the adenoma and the adenocarcinoma indicates its potential value in the early diagnosis of colonic cancer.

Adenocarcinoma ; metabolism ; pathology ; Adenoma ; metabolism ; pathology ; Adult ; Aged ; Biomarkers, Tumor ; metabolism ; Cell Cycle Proteins ; genetics ; metabolism ; Colonic Neoplasms ; metabolism ; pathology ; Female ; Humans ; Male ; Middle Aged ; Minichromosome Maintenance Complex Component 2 ; Nuclear Proteins ; genetics ; metabolism ; RNA, Messenger ; Young Adult

Adenoma, Oxyphilic ; classification ; pathology ; Carcinoma, Renal Cell ; classification ; metabolism ; pathology ; Humans ; Kidney ; pathology ; Kidney Neoplasms ; classification ; genetics ; pathology ; therapy ; Molecular Biology ; methods ; trends

BACKGROUND/AIMS: DNA double strand break (DSB) is one of the critical types of DNA damage. When unrepaired DSB is accumulated in the nucleus of the cells having mutations in such genes as p53, it will lead to chromosomal instability and further more to mutation of tumor-activating genes resulting in tumorogenesis. Some of malignant cancers and its premalignant lesions were proven to have DSB in their nuclei. The aim of this study was to define the differences in expression of 53BP1 and gamma-H2AX, the markers of DSB, among normal, gastric adenoma, and gastric adenocarcinoma tissues. METHODS: Tissue microarray was made with the tissues taken from 121 patients who underwent gastrectomy for gastric adenocarcinoma, and 51 patients who underwent endoscopic mucosal resection for gastric adenoma. Immunochemical stain was performed for the marker of DSB, 53BP1 and gamma-H2AX in the tissue microarray. The normal tissues were collected from histologically confirmed tissues with no cellular atypia obtained from the patients with gastric adenocarcinoma. RESULTS: In gastric carcinoma cells, 53BP1 and gamma-H2AX were highly expressed as compared to normal epithelial cells and gastric adenoma (p<0.01). There were no differences in the expression of 53BP1 and gamma-H2AX between normal epithelium and gastric adenoma. The expression of 53BP1 in the adenoma with grade II and III atypism was more elevated than in those with grade I atypism. The expression of 53BP1 and gamma-H2AX were not significantly different according to the clinicopathologic parameters in the patients with gastric adenocarcinoma. CONCLUSIONS: The DSB in DNA seems to be associated with the development of gastric adenocarcinoma, but does not affect the premalignant adenoma cells.
Adenocarcinoma/genetics/*metabolism/secondary ; Adenoma/genetics/*metabolism/pathology ; Adult ; Aged ; Aged, 80 and over ; Chromosomal Instability ; *DNA Breaks, Double-Stranded ; Female ; Histones/metabolism ; Humans ; Intracellular Signaling Peptides and Proteins/metabolism ; Male ; Middle Aged ; Neoplasm Staging ; Stomach Neoplasms/genetics/*metabolism/pathology

OBJECTIVETo study Twist expression in thyroid papillary carcinoma (PTC) by immunohistochemistry and to assess its usefulness as marker in the differential diagnosis of PTC, follicular adenomas (FA) and benign papillary lesions (BPL).

METHODSFifty cases of PTC, 48 cases of FA and 47 cases of BPL were evaluated using manual tissue chip and SP immunohistochemical stain to detect the expression of Twist and HBME-1, and comparing the staining to that of cytokeratin 19 (CK19).

RESULTSIn PTC, positive rates of Twist, HBME-1 and CK19 were 100% (48/48), 94.0% (47/50) and 78.0% (39/ 50) respectively; in FA, positive rates were 0, 6.7% (3/45) and 0 respectively; in BPL, positive rates were 7.0% (3/34), 2.1% (1/47) and 0, respectively. The differences between PTC and FA and between PTC and BPL were both statistically significant (P = 0. 000). The sensitivity of Twist, HBME-1 and CK19 was 100%, 94.0% and 78.0%; the specifity was 96.4%, 95.7% and 100%; overall accurary was 97.7%, 95.1% and 91.9%, respectively.

CONCLUSIONSPositive rates of Twist is higher than the other markers in PTC. Immunohistochemical staining of Twist has important significance in the differential diagnosis of thyroid lesions. Twist immunohistochemistry maybe helpful in diagnosis and differential diagnosis of PTC.

Adenocarcinoma, Follicular ; metabolism ; Adenocarcinoma, Papillary ; pathology ; Adenoma ; diagnosis ; metabolism ; Biomarkers, Tumor ; immunology ; Carcinoma, Papillary ; diagnosis ; metabolism ; pathology ; Carcinoma, Papillary, Follicular ; metabolism ; Diagnosis, Differential ; Galectin 3 ; genetics ; metabolism ; Immunohistochemistry ; Keratin-19 ; genetics ; Keratins ; genetics ; metabolism ; Nuclear Proteins ; genetics ; metabolism ; Thyroid Neoplasms ; diagnosis ; metabolism ; pathology ; Thyroid Nodule ; pathology ; Twist-Related Protein 1 ; genetics ; metabolism

OBJECTIVETo explore the significance of mitochondrial D-loop alterations in hyperplastic pancreatic ductal cells in vicinity of pancreatic cancer coexisting with chronic pancreatitis.

METHODSMalignant lesions and foci of pancreatic ductal intraepithelial neoplasia of the pancreas and paired normal gastric mucosal epithelial cells from the same patients, respectively, were assessed by polymerase chain reaction. Somatic point mutations and sequence variants of D-loop were searched by direct sequencing of the mitochondrial genome. D-loops were sequenced by BLAST to identify their mutations.

RESULTSEleven of 12 pancreatic cancers displayed at least one D-loop variants and one tumor presented heteroplasmy. There was an apparent increase in incidence of D-loop mutational rate from PanIN1 (33.3%) to PanIN3 (75%, P < 0.01).

CONCLUSIONMitochondrial D-loop alterations in the pancreas occur in the earliest premalignant lesions and exhibite an increasing occurence that parallels histological severity. These alterations may serve as a valuable marker to follow the histopathological progression of the lesions. Large number of further studies are required to clarify clinical implications of the mitochondrial DNA alterations.

Adenoma ; complications ; genetics ; Adult ; Aged ; Base Sequence ; DNA, Mitochondrial ; genetics ; Epithelial Cells ; metabolism ; pathology ; Female ; Humans ; Male ; Middle Aged ; Mutation ; Pancreatic Ducts ; metabolism ; pathology ; Pancreatic Neoplasms ; complications ; genetics ; Pancreatitis, Chronic ; complications ; genetics ; Precancerous Conditions ; complications ; genetics ; Sequence Analysis, DNA

Adenoma ; genetics ; metabolism ; pathology ; surgery ; Adult ; Carcinoma, Renal Cell ; genetics ; metabolism ; pathology ; Chromosomes, Human, Pair 3 ; genetics ; Chromosomes, Human, Pair 7 ; genetics ; Diagnosis, Differential ; Diploidy ; Female ; Follow-Up Studies ; Humans ; Kidney Neoplasms ; genetics ; metabolism ; pathology ; surgery ; Male ; Middle Aged ; Retrospective Studies ; S100 Proteins ; metabolism ; Vimentin ; metabolism ; WT1 Proteins ; metabolism ; Wilms Tumor ; metabolism ; pathology

OBJECTIVETo detect the BRAF(V599E) mutation and the RET/PTC chimeric gene in benign and malignant thyroid diseases and to explore their correlation with the clinicopathologic features of papillary thyroid carcinoma (PTC).

METHODSPCR and RT-PCR were employed to detect BRAF(V599E) mutation and RET/PTC chimeric genes in 95 frozen and parraffine-embeded thyroid tissue.

RESULTS(1) BRAF(V599E) mutation was detected only in PTC (56%, 37/66) and had a high prevalence in both classic and tall cell types (70%, 29/41 and 2/3). However, follicular types of PTC and other benign and malignant thyroid diseases were negative for BRAF(V599E) mutation. (2) Fourteen (21.2%) PTC cases expressed RET/PTC chimeric gene. Among them, 5 cases (7.6%) were RET/PTC1 and 9 cases (13.6%) were RET/PTC3 respectively. (3) Statistic data did not show any correlation between the BRAF(V599E) mutation, RET/PTC and clinicopathologic features of PTC (P > 0.05). There was no overlap between BRAF(V599E) mutation and RET/PTC rearrangements.

CONCLUSIONS(1) BRAF(V599E) mutation and RET/PTC rearrangements were unique to PTC. The high prevalence of BRAF(V599E) mutation indicates that it is an important molecular hallmark of PTC. (2) BRAF(V599E) mutation rate was high in classic type PTC and tall cell type inferred that BRAF(V599E) mutation played an important role in their etiopathogenesis. (3) There was no overlap between BRAF(V599E) mutation and RET/PTC rearrangements suggest that they are alternative events in PTC.

Adenocarcinoma, Follicular ; genetics ; pathology ; Adenoma ; genetics ; pathology ; Adolescent ; Adult ; Aged ; Carcinoma, Papillary ; genetics ; pathology ; Diagnosis, Differential ; Female ; Gene Rearrangement ; Hashimoto Disease ; genetics ; pathology ; Humans ; Lymphatic Metastasis ; Male ; Middle Aged ; Oncogene Proteins, Fusion ; genetics ; metabolism ; Point Mutation ; Protein-Tyrosine Kinases ; genetics ; metabolism ; Proto-Oncogene Proteins B-raf ; genetics ; metabolism ; Thyroid Neoplasms ; genetics ; pathology

OBJECTIVETo investigate the significance and mechanisms of overexpression of p21-activated kinase 1 gene (PAK1) in epithelial ovarian neoplasms.

METHODSImmunohistochemistry, fluorescence in situ hybridization and terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling methods were used to examine the protein expression and amplification of PAK1 and cell apoptosis in 30 benign ovarian adenomas, 20 borderline tumors and 80 ovarian carcinomas by tissue microarray.

RESULTSIn immunohistochemistry study, overexpression of PAK1 protein was observed in 7 (25.9%) informative benign ovarian adenomas, 7 (36.8%) borderline tumors and 53 (68.8%) ovarian carcinomas. A significant inverse correlation of PAK1 overexpression and cell apoptosis was observed in these epithelial ovarian neoplasm cohorts (P = 0.002). In addition, 27/31 (87.1%) poorly differentiated (G3) carcinomas showed overexpression of PAK1, the frequency was significantly higher than that in tumors of G1 - G2 (26/46, 56.5% , P =0.01). In fluorescence in situ hybridization study, only 2 (4.7%) informative ovarian carcinomas showed amplification of PAK1 gene. None of the borderline and benign ovarian tumors showed PAK1 amplification.

CONCLUSIONOverexpression of PAK1 protein may be involved in the tumorigenesis of epithelial ovarian neoplasms and it is associated closely with the malignant histological phenotype of ovarian carcinomas. Mechanism other than gene amplification of PAK1 may play a more important role in the regulation of protein expression of PAK1 in ovarian tumors.

Adenoma ; genetics ; metabolism ; pathology ; Apoptosis ; Cystadenocarcinoma, Mucinous ; genetics ; metabolism ; pathology ; Cystadenocarcinoma, Serous ; genetics ; metabolism ; pathology ; Female ; Gene Amplification ; Gene Expression Regulation, Neoplastic ; Humans ; Immunohistochemistry ; In Situ Hybridization, Fluorescence ; In Situ Nick-End Labeling ; Middle Aged ; Neoplasm Staging ; Ovarian Neoplasms ; genetics ; metabolism ; pathology ; p21-Activated Kinases ; genetics ; metabolism

OBJECTIVETo investigate the incidence and clinicopathologic significance of MSI and LOH on 3P in breast carcinoma and its precancerous lesions, intraductal papillary adenoma and ductal carcinoma in situ.

METHODS41 paired sporadic invasive breast carcinomas, 13 archival precancerous lesion specimens of the breast and 14 couples of benign hyperplasia were collected. Twelve microsatellites on chromosomes 2p, 3p, 5q, 6q, 16q, 17q, eleven markers on chromosome 3p were amplified for MSI and LOH, respectively, by polymerase chain reaction ( PCR ) with designed primers and detecting after polyacrylamide gel electrophoresis. In addition, the expression of protein of hMSH2, hMLHI, FHIT, ER, and PR were detected by immunohistochemistry.

RESULTSMSI was observed, at least two microsatellite markers, in 15 out of 41 (36. 6%) of the carcinomas, almost all belonging to poorly or intermediately differentiated carcinoma. Instability was shown in 9 of the 13 cases of precancerous lesions, but only 2 among them had more than 2 MSI sites. There was no MSI in benign hyperplasia. MSI was targeted predominately at D3S1766, D2S2739 in both carcinomas and precancerous lesions. Of the 11 loci examined, D3S1295, D3S1029 and D3S1038 were identified as the locus with most frequent LOH which were all correlated significantly with some clinicopathological parameters such as histological type, lymph node metastasis in breast cancer, while D3S1295 and D3S1029 were the most frequent markers in precancerous lesions. LOH of D3S1295 had significant correlation with negative expression of FHIT. Positive expression of hMLH1 and hMSH2 protein was detected in breast carcinomas in scattered distribution and their positive rate was 45% and 40% , respectively. In precancerous lesions, hMLH1 and hMSH2 protein showed diffuse expression and their positive rate was 61. 54% and 76. 92% , respectively, significantly lower than that in the control tissues.

CONCLUSIONDefective expression of MMR genes is closely associated with the development of breast cancer. Genomic instability might play a role in the early stage during multi-step mammary carcinogenesis. MSI indicates poor histological differentiation in breast carcinoma. D3S1766 and D2S2739 might be the sensitive sites to detect MSI in breast carcinoma and precancerous lesions. The smallest common LOH deletion regions seem likely to be situated between 3p14 and 3p25, indicating the existence of breast tumor related genes in those regions and some of them might affect tumor development.

Acid Anhydride Hydrolases ; metabolism ; Adaptor Proteins, Signal Transducing ; metabolism ; Adenoma ; genetics ; metabolism ; pathology ; Adult ; Aged ; Breast ; metabolism ; pathology ; Breast Neoplasms ; genetics ; metabolism ; pathology ; Carcinoma, Ductal, Breast ; genetics ; metabolism ; pathology ; Chromosome Deletion ; Chromosomes, Human, Pair 3 ; genetics ; DNA Mismatch Repair ; Female ; Humans ; Hyperplasia ; Immunohistochemistry ; Loss of Heterozygosity ; Lymphatic Metastasis ; Microsatellite Instability ; Middle Aged ; MutL Protein Homolog 1 ; MutL Proteins ; Neoplasm Proteins ; metabolism ; Neoplasm Staging ; Nuclear Proteins ; metabolism ; Polymerase Chain Reaction ; Precancerous Conditions ; genetics ; metabolism ; pathology ; Receptors, Estrogen ; metabolism ; Receptors, Progesterone ; metabolism