OBJECTIVETo investigate the correlation between the expression of key proto-oncogenes playing major roles in tumorigenic process and abnormal sarring.

METHODSImmunohistochemical technique was performed to detect the expressions of c-myc, c-fos and ras p21 proteins on hypertrophic scars, keloids and normal skin. Image analysis was used to compare their quantitative difference of expression.

RESULTSC-myc and c-fos expressions on the nucleus of fibroblasts of hypertrophic and keloid scars were significantly higher than normal skin controls, and there was no difference between the two lesions. Ras p21 expression was not detected on the fibroblasts of hypertrophic and keloid scars.

CONCLUSION1. c-myc and c-fos oncogenes are activated on hypertrophic and keloid scars, which may contribute to proliferation and differentiation of fibroblasts, synthesis and degradation of collagen and regulation of cytokines and induce abnormal scarring, the mechanisms of their effects remain to be further studied. 2. Ras gene may not mutate or its mutations may not play a major role in the process of abnormal scarring. 3. Only part of proto-oncogenes moderately expressed on abnormal scars. The expression of multiple oncogenes does not coexist in abnormal scars may be the cause of their less chances to induce malignant transformation.

Cicatrix, Hypertrophic ; metabolism ; Humans ; Immunohistochemistry ; Proto-Oncogene Proteins c-fos ; analysis ; Proto-Oncogene Proteins c-myc ; analysis ; Proto-Oncogene Proteins p21(ras) ; analysis ; Proto-Oncogenes

OBJECTIVETo investigate mutations frequencies of KRAS,NRAS and BRAF genes in colorectal carcinoma.

METHODSTissue specimens from 200 colorectal cancer patients at diagnosis were collected and subject to KRAS,NRAS and BRAF mutation analyses by PCR-based direct DNA sequencing targeting exons 2, 3 and 4 of KRAS gene, exons 2, 3 and 4 of NRAS gene and exon 15 of BRAF gene.

RESULTSActivating mutations were detected in KRAS (44%, 88/200), NRAS (2%, 4/200) and BRAF (5%, 10/200) in this study cohort.Among KRAS mutations, 64.8% (57/88) occurred in codon 12 and 12.5% (11/88) occurred in codon 13. KRAS gene mutation in exon 3 mainly involved codons 59 and 61. KRAS gene mutation in exon 4 mainly involved codons 117 and 146.

CONCLUSIONSMutations at exon 2 of KRAS gene have the highest frequency in colorectal carcinoma. Expanding the detection sites of KRAS gene combined with NRAS and BRAF genes may help to identify patients who will most likely benefit from targeted therapies.

Base Sequence ; Codon ; Colorectal Neoplasms ; genetics ; DNA Mutational Analysis ; Exons ; Female ; Genes, ras ; Humans ; Mutation ; Proto-Oncogene Proteins ; Proto-Oncogene Proteins B-raf ; genetics ; Sequence Analysis, DNA

PURPOSE: To assess the prevalence of KRAS, BRAF, and TP53 mutations in cases of low-grade and high-grade serous carcinomas and to evaluate the clinical outcomes of these morphologically distinct carcinomas. MATERIALS AND METHODS: Patients with primary invasive serous carcinomas were classified according to the universal grading system. Grade 2 serous tumors were excluded. A total of 100 patients were included for clinical evaluation. Thirty-seven patients, including 20 with low-grade and 17 with high-grade carcinomas, were selected for mutational analysis. RESULTS: The low-grade carcinoma group was characterized by young age and premenopausal period compared with the high-grade carcinoma group, but there were no statistically significant differences in stage, metastasis of lymph node and residual disease. There were no statistically significant differences in survival rates, however, the low-grade carcinoma group showed a trend for improved progression-free survival compared with the high-grade carcinoma group of early stage (p = 0.064). Mutations in KRAS and BRAF were found in 6 (30%) and 2 (10%) patients in the low-grade carcinoma group, respectively, however, they were not found in the high-grade carcinoma group. KRAS and BRAF mutations were mutually exclusive, and both mutations were observed in 40% (8/20). The frequency of TP53 mutations in low-grade and high-grade carcinoma groups were found in 20% (4/20) and 70.6% (12/17), respectively (p = 0.009). CONCLUSION: Low-grade serous carcinoma shows mutation pattern different from that with high-grade carcinoma. As there were no significant differences in stage distribution and survival, especially in advanced stage, we suggest that more studies are needed to segregate these patients into distinct disease entities.
Adult ; Cystadenocarcinoma, Serous/*genetics ; DNA Mutational Analysis ; Female ; Humans ; Middle Aged ; Ovarian Neoplasms/*genetics ; Proto-Oncogene Proteins/*genetics ; Proto-Oncogene Proteins B-raf/*genetics ; ras Proteins/*genetics

OBJECTIVETo investigate the expression of cytokeratins and ret in thyroid papillary carcinoma (TPC) and their diagnostic value.

METHODSDuring the period of October 1999 to March 2002, 69 cases of TPC (42 cases with adjacent normal thyroid tissue) and 14 cases of nodular goiter with papillary hyperplasia were enrolled into the study. Immunohistochemistry for CK19, CK17, CK8, CK20 and ret was performed in all cases using EnVision and LSAB methods respectively.

RESULTSThe positive rates for CK19 and ret in TPCs were 85.5% and 68.1% respectively, which were significantly (P < 0.01) higher than those in nodular goiter and normal thyroid tissue (25.0% and 5.4% respectively). The expression of CK17 was also observed in a few cases of TPCs (11/69, 15.9%), which was mainly localized in areas of squamous metaplasia, poorly differentiated carcinoma and/or in the small infiltrative foci. The positive rates for CK8 were 75.4% and 26.8% in TPCs and benign thyroid tissue respectively. All cases were negative for CK20.

CONCLUSIONSCK19, CK17 and ret expressions are significantly higher in TPCs than benign thyroid tissue; and this characteristic can have important diagnostic value.

Carcinoma, Papillary ; metabolism ; pathology ; Humans ; Immunohistochemistry ; Keratins ; analysis ; biosynthesis ; Proto-Oncogene Proteins ; biosynthesis ; Proto-Oncogene Proteins c-ret ; Receptor Protein-Tyrosine Kinases ; biosynthesis ; Thyroid Neoplasms ; metabolism ; pathology

Cell Membrane ; metabolism ; Gastrointestinal Stromal Tumors ; diagnosis ; metabolism ; Humans ; Immunohistochemistry ; Proto-Oncogene Proteins c-kit ; analysis

OBJECTIVETo define the frequency and spectrum of c-kit gene mutations in gastrointestinal stromal tumors (GIST).

METHODSFifty two cases of GIST and 28 cases of other tumors were examined for mutations in exon 11, 9 and 13 of c-kit gene using PCR amplification and DNA sequencing.

RESULTSFourteen out of 25 malignant GIST (56%), while 2 of 27 benign and borderline GIST (7.4%) revealed mutations in exon 11 of c-kit gene (P < 0.01). Most of the mutations consisted of in-frame deletion or replication from 3 to 48 bp in heterozygous and homozygous fashions, but none of the mutations disrupted the downstream reading frame of the gene. Point mutation and deletion concentrated at 550 - 570 codons but replication clustered within 570 - 585 codons. The mutation pattern in recurrence tissues was the same as the primary ones. Normal tissues adjacent to GIST with or without c-kit gene mutations showed wild type c-kit gene sequence. No mutation was found in exon 9 and 13. Neither c-kit gene expression nor gene mutations was found in 3 leiomyomas, 8 leiomyosarcomas, 2 schwannomas, 2 intra-abdomenal fibromitoses and 8 adenocarcinomas.

CONCLUSIONThe mutations in exon 11 of c-kit gene might partially represent one of the molecular mechanisms of GIST. It can be used as a marker for distinguishing benignancy and malignancy of GIST. The mutations did not involve the reading frame. Except for long frame deletion, most mutations also did not affect protein expression. Mutation of c-kit gene in GIST provides a new genotypic marker to distinguish GIST from authentic leiomyomas, leiomyosarcomas, schwannomas and etc.

Base Sequence ; Gastrointestinal Neoplasms ; genetics ; Humans ; Molecular Sequence Data ; Mutation ; Proto-Oncogene Proteins c-kit ; analysis ; genetics ; Proto-Oncogenes

Colorectal Neoplasms ; genetics ; DNA Mutational Analysis ; standards ; Humans ; Mutation ; Proto-Oncogene Proteins B-raf ; genetics ; ras Proteins ; genetics

A primary benign schwannoma of the liver is extremely rare. Only nine cases have been reported in the medical literature worldwide and no case has been reported in Korea previously. A 36-yr-old woman was admitted to our hospital with vague epigastric pain. The ultrasound and computed tomography scan revealed a multiseptated cystic mass in the right lobe of the liver. The mass was resected; it was found to be a 5x4x2 cm mass filled with reddish yellow fluid. The histological examination confirmed the diagnosis of a benign schwannoma, proven by positive immunoreaction with the neurogenic marker S-100 protein and a negative response to CD34, CD117 and smooth muscle actin. This is the first report of a benign schwannoma of the liver parenchyma in a Korean patient.
Adult ; Antigens, CD34/analysis ; Female ; Humans ; Liver Neoplasms/diagnosis/*pathology ; Neurilemmoma/diagnosis/*pathology ; Proto-Oncogene Proteins c-kit/analysis

Humans ; In Situ Hybridization, Fluorescence ; Membrane Proteins ; analysis ; NF-kappa B ; analysis ; Proto-Oncogene Proteins c-bcl-2 ; analysis ; Tissue Array Analysis ; methods ; Tumor Cells, Cultured

OBJECTIVETo study the expression and significance of apoptosis-related protein p53, Bcl-2, and Bax during the development of oral squamous cell carcinoma (SCC).

METHODSThe expression was observed in 10 normal oral epithelia, 48 dysplasia epithelia and 42 SCC by immunohistochemical evaluation.

RESULTSIn normal mucosa, the positive rate of p53, Bcl-2 and Bax were 0%, 20% and 60%. In dysplasia epithelia, the positive rate of p53 is increased (P < 0.05), the positive rate of Bcl-2 and Bax remained no significant change (P > 0.05), but the positive intensity in severe dysplasia was higher than in mild group. In SCC, the positive rate of Bcl-2 increased significantly (compared with dysplasia, P < 0.05), while the expression of Bax was decreased with the increase of SCC histological grade. Further analysis showed the correlation was evident in p53 and Bax in dysplasia, and in p53 and Bcl-2 in SCC.

CONCLUSIONSIn dysplasia, p53 gene mutation results in accumulation of dysplasia cells. In SCC, the cooperation of p53, Bcl-2 and Bax results in the progression of SCC. Apoptosis genes could work either independently or cooperatively.

Apoptosis ; genetics ; Carcinoma, Squamous Cell ; chemistry ; Humans ; Immunohistochemistry ; Mouth Mucosa ; chemistry ; pathology ; Mouth Neoplasms ; chemistry ; Proto-Oncogene Proteins ; analysis ; Proto-Oncogene Proteins c-bcl-2 ; analysis ; Tumor Suppressor Protein p53 ; analysis ; bcl-2-Associated X Protein