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Biomedical subjects

S Y Song

Publications and source records attributed to S Y Song.

At least 19 recordsLinked to original sources
PubMed2006

Increased expression of pAKT is associated with radiation resistance in cervical cancer.

Phosphorylated AKT (pAKT) is a major contributor to radioresistance in human cancers. The aim of this study was to investigate the association of pAKT expression and radiation resistance in cervical cancer. A retrospective review was made of the records of 27 women who received primary radiation therapy due to locally advanced cervical cancer (LACC) with FIGO stage IIB-IVA. Nine patients regarded as radiation resistant developed local recurrences with a median progression free interval of 9 months. Eighteen patients did not show local recurrences, and were regarded as a radiation-sensitive group. Using pretreatment paraffin-embedded tissues, we evaluated pAKT expression by immunohistochemistry. A significant association was found between the level of pAKT expression and local recurrence. Immunohistochemical staining for pAKT was significantly more frequent in the radiation-resistant than in the radiation-sensitive group (P=0.004). The mean progression-free survival was 86 months for patients with pAKT-negative staining (19 cases) and 44 months for patients with pAKT-positive expression (eight cases) (P=0.008). These results suggest that signalling from phosphatidylinositide 3-kinase/pAKT can lead to radiation resistance, and that evaluation of pAKT may be a prognostic marker for response to radiotherapy in LACC.

Adult↗
PubMed2006

Promoter methylation of helicase-like transcription factor is associated with the early stages of gastric cancer with family history.

BACKGROUND: To investigate the clinicopathological significance of promoter methylation of the helicase-like transcription factor (HLTF) in primary gastric cancer. PATIENTS AND METHODS: Two-hundred fifty six patients participated in this study. Methylation status of HLTF gene was evaluated in fresh-frozen tissues by the methylation-specific polymerase chain reaction. All statistical analyses were two-sided, with a 5% type I error rate. RESULTS: Aberrant methylation of HLTF was found in 98 (38%) of 256 gastric cancer patients. HLTF methylation was significantly associated with a family history in the early stages of gastric cancer, regardless of histologic types. In intestinal-type cases, HLTF methylation occurred in 15 (56%) of 27 patients with family histories, and in 26 (31%) of 85 patients without family histories (P = 0.02). In diffuse-type cases, patients with family histories were also found to exhibit a higher prevalence of HLTF methylation than those without family histories (61% vs. 34%; P = 0.009). HLTF methylation in both of the histologic types occurred in about 70-90% of the early stage cases in which the patient had a family history and in 15-30% of cases in which the patient did not have a family history. In our multivariate logistic regression analysis, the stage 1-2 cases with family histories were determined to carry a higher risk of HLTF methylation than did the stage 3-4 cases without family histories in both the intestinal-type (OR = 6.01, 95% CI = 1.20-30.01, P = 0.02) and the diffuse-type cancers (OR = 8.25, 95% CI = 1.67-40.86, P = 0.009). CONCLUSIONS: These results suggest that HLTF methylation may play a crucial role in the early stages of gastric carcinogenesis in patients with family histories and may be a valuable susceptible marker for the risk of gastric cancer in individuals with family histories.

Aged↗
PubMed2006

Enteroendocrine cell counts correlate with visceral hypersensitivity in patients with diarrhoea-predominant irritable bowel syndrome.

The objective of this study was to determine whether or not the number of enteroendocrine cells (ECs) in the gut is related to visceral hypersensitivity in patients with diarrhoea-predominant irritable bowel syndrome (D-IBS). Twenty-five subjects with D-IBS (mean, 43.1 years; 16 women, nine men) were recruited into our study, along with 13 healthy controls (mean, 40.7 years; nine women, four men). Maximally tolerable pressures were evaluated via barostat testing, and the levels of ECs were immunohistochemically identified and quantified via image analysis. The numbers of ECs between the D-IBS subjects and the controls were not significantly different in the terminal ileum, ascending colon and rectum. However, the maximally tolerable pressures determined in the D-IBS subjects were significantly lower than those of the control subjects (P < 0.01), and we detected a significant relationship between the maximally tolerable pressures and the numbers of ECs in the rectum (r = -0.37, P < 0.01). Rectal sensitivity was enhanced to a greater degree in D-IBS patients exhibiting an elevated level of rectal ECs. This study provides some evidence to suggest that ECs play an important role in visceral hypersensitivity.

Adult↗
PubMed2005

Giant fibrovascular polyp of the esophagus: CT findings.

Giant fibrovascular polyp of the esophagus is a rare intraluminal benign tumor that is covered with normal esophageal mucosa, which consists of fibrous tissue, adipose tissue, and vascular structures. We report a case of a giant fibrovascular polyp of the esophagus in which feeding vessels were well visualized within the stalk of the mass at contrast-enhanced helical computed tomography.

Esophageal Neoplasms↗
PubMed2005

Intraoperative tumor localization using laparoscopic ultrasonography in laparoscopic-assisted gastrectomy.

BACKGROUND: During laparoscopic-assisted gastrectomy, it is impossible to identify early gastric cancer (EGC) lesions; therefore, a precise localization technique is needed. In this study, we used laparoscopic ultrasonography (LUS) after endoscopic clipping as a method of localizing EGC and evaluated the effectiveness of this method. METHODS: A prospective study of 17 patients who had undergone laparoscopic-assisted gastrectomy was performed. Three endoscopic clips were applied just proximal to the tumor during the preoperative endoscopy. The applied clips were detected from the serosal side of the stomach using LUS. The serosal surface of the lesion was marked with dye. RESULTS: In all patients, endoscopic clips were applied proximal to the lesion without complications, and the applied clips were confirmed by plain abdominal radiography. The clips were successfully detected by LUS in all patients. In the resected specimen, the serosal surface, marked with dye, was always just above the clips in the anterior wall or on the anterior wall opposite the clips applied in the posterior wall. The mean detection time was 4.7 min (range, 2-8). With this procedure, two patients underwent total gastrectomy and 15 patients underwent distal subtotal gastrectomy with gastroduodenostomy or gastrojejunostomy. Histological examination confirmed that the resection margins were tumor free in all patients. There was no operative morbidity related to the LUS procedure. CONCLUSIONS: Using LUS to detect endoscopic clips is an easy, safe, and accurate method to localize EGC lesions in laparoscopic-assisted gastrectomy.

Adult↗
PubMed2005

Characteristics of submucosal gastric carcinoma with lymph node metastatic disease.

AIM: To study the correlation between lymph node metastatic disease and various pathological parameters. Lymph node metastasis is the most important factor in determining the prognosis of patients with early gastric cancer and is significantly associated with the submucosal invasion of neoplastic cells. However, the depth of submucosal layer as well as the depth of submucosal tumour invasion varies among different cases. METHODS AND RESULTS: We studied various pathological parameters including the macroscopic appearance, location, size, area, differentiation, invasion depth, vascularity and fibrosis of submucosal gastric carcinomas (SMGC), using 248 age- and sex-matched tissue samples. The presence of lymphatic emboli, a larger area, greater size, a non-flat gross type and an increased vascularity of the tumour were significantly associated with node-positive SMGC. Among the three depth-related parameters, the ocular scale measurement, the sm3 method and the sm2 method, only the ocular scale measurement showed a significant correlation with node-positive SMGC. Using multivariate analysis, the incidence of lymph node metastasis increased in the lymphatic tumour emboli and in the tumours that invaded more than half of the submucosal layer. CONCLUSIONS: These histological indicators seem to be a feasible and easy way to predict lymph node metastatic disease from limited surgery specimens. Pathologists should carefully investigate the lymphatic invasion of tumour cells and measure the invasion depth of the tumour.

Adult↗
PubMed2005

Expression of the licensing factors, Cdt1 and Geminin, in human colon cancer.

Licensing of chromatin for replication is an evolu-tionarily conserved step in the control of cell division and genomic integrity. Proteins that participate in licensing have been recently documented to denote the proliferative state of cells and they have been proposed as diagnostic and prognostic markers in human cancer. Cdt1 was recently discovered as an important licensing factor, that is inhibited by Geminin. In the present study we analyzed Cdt1 and Geminin expression in human colon cancer. We showed that Cdt1 protein is highly expressed in human neoplastic lesions of the colon while its cell-cycle phase-specific expression profile appears preserved during human carcinogenesis. Similarly, Geminin, Cdt1's inhibitor, is also overexpressed in colon carcinomas and its expression correlates with significant clinicopathological parameters of the disease. Moreover, both Cdt1 and Geminin expression are severely downregulated upon differentiation of Caco-2 cells, an in vitro model of intestinal epithelial differentiation.

Adenoma↗
PubMed2004

A phase II trial of capecitabine in previously untreated patients with advanced and/or metastatic gastric cancer.

BACKGROUND: Capecitabine (Xeloda) is a novel, oral, selectively tumor-activated fluoropyrimidine with proven activity in the treatment of advanced colorectal cancer. This trial was conducted to evaluate the efficacy, safety and feasibility of capecitabine in previously untreated patients with advanced and/or metastatic gastric cancer, with a view to replacing 5-fluorouracil (5-FU) in such patients. PATIENTS AND METHODS: Forty-four patients received capecitabine 1250 mg/m2 twice daily (2500 mg/m2/day) for 14 days followed by 7 days of rest, for up to six cycles. RESULTS: Capecitabine produced an objective response rate of 34% (all partial responses) and stable disease in 14 patients (30%). The median time to disease progression (TTP) was 3.2 months [95% confidence interval (CI) 2.7-6.4 months] and median overall survival was 9.5 months (95% CI 6.9-13.2 months). Hand-foot syndrome (HFS), nausea, anorexia, diarrhea and vomiting were the most common adverse events. While HFS was the most frequent grade 3/4 toxicity (National Cancer Institute Common Toxicity Criteria), only 9% of patients experienced grade 3 HFS. Severe myelosuppression was not reported during the study. CONCLUSIONS: Capecitabine monotherapy is active and well tolerated as first-line therapy in patients with advanced/metastatic gastric cancer. Larger comparative trials investigating capecitabine-based combination regimens in patients with advanced gastric cancer are warranted.

Administration, Oral↗
PubMed2004

Characteristics of intramucosal gastric carcinoma with lymph node metastatic disease.

AIM: Recent trends in treatment strategy for early gastric cancer (EGC) are towards minimal surgical procedures, such as endoscopic mucosal resection and laparoscopic partial resection. There is a possibility of incomplete removal of regional lymph nodes in minimal procedures, which may subsequently decrease the chance of a cure. Therefore, it is essential to be able to predict lymph node status and to make careful selection of candidates for mucosal resection. METHODS AND RESULTS: We studied the relationship between lymph node status and various pathological parameters including macroscopic appearance, location, size, differentiation, presence of ulceration, vascularity, presence of gastritis cystica profunda-like glandular proliferation, disruption of the muscularis mucosae and invasion into the muscularis mucosae, using age- and sex-matched samples of 40 node-positive and 80 node-negative tumours to define the characteristics of intramucosal EGCs. Histological differentiation (P < 0.001), increased submucosal vascularity (P < 0.05), breakdown of the muscularis mucosae (P < 0.05), and invasion of tumour cells into the muscularis mucosae (P < 0.05) were correlated with the lymph node status of intramucosal gastric carcinoma. Furthermore, diffuse type histology (P < 0.001) and deep invasion into the muscularis mucosae (P < 0.05) were indicators of node-positive intramucosal EGCs. CONCLUSIONS: These histological indicators are easily accessible and seem to predict lymph node metastatic disease in limited surgical specimens. Patients should be carefully selected despite the recent trend toward less invasive resection of EGCs, especially for those apparently confined to the mucosa.

Adult↗
PubMed2003

Pathologic characteristics of prostatic adenocarcinomas: a mapping analysis of Korean patients.

Pathologic characteristics of the prostatic adenocarcinoma in Koreans are not clear. We studied 132 cases of prostatectomy specimens using mapping analysis to discover the pathologic characteristics of the Korean prostatic adenocarcinoma. Mean values were as follows: serum prostate-specific antigen level (sPSA), 16.4 ng/ml; tumor volume, 27.5%; size, 2.4 cm; Gleason score, 7.7; and p53 expression, 9.8%. Rates of multifocal tumors and high-grade prostatic intraepithelial neoplasm (HPIN) were 33.3 and 65.2%. The Gleason score, tumor volume%, tumor size and sPSA were correlated with each other. Korean prostatic adenocarcinomas showed higher Gleason scores, lower rates of HPIN and multifocality, and lower p53 expression in comparison to Western prostatic adenocarcinomas. These data may be a basis for pathologic characteristics of Korean prostatic adenocarcinoma that has now been increasing.

Adenocarcinoma↗
PubMed2002

Structure of an acidic phospholipase A(2) from the venom of Deinagkistrodon acutus in a new crystal form.

The three-dimensional structure of an acidic phospholipase A(2) purified from the venom of Deinagkistrodon acutus (Agkistrodon acutus) was determined in a new crystal form by molecular replacement at 0.28 nm resolution with a crystallographic R factor of 21.9% (R-free=25.7%) and reasonable stereochemistry. Being similar to the previous reported crystal form, a significant conformational adaptation of segment 14-23 at the dimer interface was observed. This segment was related to the "interface recognition site" (IRS). It was found that a positively charged residue at position 34 seems to be a common feature for most of hemolytic PLA(2)s belonging to group II. Structural comparison between the two crystal forms showed that NaCl had significant effects on the crystal packing, thus leading to dramatic changes of the unit cell parameters. In the new crystal form, MPD (2-methyl-2, 4-pentanediol) molecules exist in the hydrophobic channel of the enzyme.

Agkistrodon↗
PubMed2001

Clinical significance of molecular genetic changes in sporadic invasive pituitary adenomas.

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↗
PubMed2001

Multiple G-protein-coupled receptors mediate presynaptic inhibition at single excitatory synapses in the rat visual cortex.

Modulation of excitatory synaptic transmission by agonists for several neurotransmitter receptors was investigated at intrinsic cortical synapses derived from single presynaptic neurons. Excitatory postsynaptic currents (EPSCs) were recorded from layer 5 pyramidal neurons in the rat visual cortex in response to minimal stimulation within the same layer. 5-hydroxytryptamine, adenosine, baclofen, carbachol and DCG-IV all suppressed EPSCs with an increase in paired-pulse ratio. These agonists reduced the frequency of miniature EPSCs without significantly affecting their amplitude distribution. These results suggest that glutamatergic excitatory transmission in the neocortex is under the control of presynaptic inhibition mediated by multiple neuromodulator receptors co-expressed in single presynaptic terminals.

Adenosine↗
PubMed2001

Cytologic clue of so-called nodular histiocytic hyperplasia of the pleura.

So-called "nodular histiocytic hyperplasia" (NHH) is a benign histiocytic lesion caused by mechanical irritation, inflammation, and tumor. Frequently, it has been confused with mesothelial lesions and other malignant neoplasms. The diagnostic clue is proliferating cells in the lesion showing diffuse, strong immunoreactivity against the histiocytic marker, CD68. Recently, we encountered a case of so-called NHH of the pleura and confused it with various malignant neoplasms on histologic examination. An 80-yr-old Korean female presented with ascites, pleural effusions, and nodules on the pleural base. Both ascites and pleural effusion tapping smears displayed moderate cellularity, vaguely nodular cellular aggregates mainly composed of mononuclear cells with bland morphology, entrapped mesothelial cells, and background lymphocytes. Pleural biopsy demonstrated vaguely nodular, compact cellular aggregates of reactive histiocytes which were immunoreactive against CD68. Based on our case, cytologic examination as well as immunohistochemical study should be stressed in the case of so-called NHH. They can provide us more credible morphologic clues to reach a more accurate diagnosis than histologic examination alone, and we can avoid invasive procedures or unnecessary therapies to patients. To our best knowledge, this is the first report describing the cytologic features of so-called NHH in the English-language literature.

Aged↗
PubMed2001

Relationship between sonographic and pathologic findings in epidermal inclusion cysts.

PURPOSE: We evaluated the sonographic findings in epidermal inclusion cysts and related them to the pathologic findings. METHODS: We retrospectively reviewed the sonograms and pathology specimens of 24 patients with pathologically proven epidermal inclusion cysts. We evaluated the lesions for shape, size, internal echogenicity, posterior sound enhancement, and presence of color Doppler signals. We classified the masses into 5 sonographic types according to their internal echogenicity. The relationship between the sonographic types and the pathologic findings was examined. RESULTS: The masses were ovoid or spherical in 17 cases (71%), lobulated in 5 (21%), and tubular in 2 (8%). The longest diameter ranged from 1 to 6 cm (mean, 3.1 cm). Twenty-three cases (96%) were associated with posterior sound enhancement. Color Doppler signals were absent in 20 cases, but some vascularity was noted in 4 ruptured epidermal cysts, in areas of granulation tissue. The most common sonographic type was a hypoechoic lesion with scattered echogenic reflectors (10 cases). Sonographic findings were related to the lamellation of keratin debris and the granulation tissue secondary to rupture. Most cases with a lobulated configuration (4 of 5) or color Doppler signals (4 of 4) were ruptured cysts. CONCLUSIONS: Epidermal inclusion cysts most often appeared sonographically as a hypoechoic mass containing variable echogenic foci without color Doppler signals. Ruptured epidermal cysts, however, may have lobulated contours and show color Doppler signals, mimicking a solid mass.

Adolescent↗
PubMed2001

Aberrant expression of cyclin D1 is associated with poor prognosis in early stage cervical cancer of the uterus.

OBJECTIVE: Many investigators have studied the expression of G1 phase regulatory protein in uterine cervical cancer. However, it is unclear which step of the genetic expression participates in cyclin D1 expression and what its prognostic meaning is. The aims of this study were to evaluate the regulatory level of cyclin D1 expression and the relationship between the expression of cyclin D1 and its inhibitor, p21WAF1/CIP1, and to evaluate their impact on the prognosis of early stage cervical cancer. METHODS: The presence of cyclin D1 mRNA was studied using Northern blot in 6 normal cervices and 7 invasive cervical cancer specimens. Western blot was used to detect the cyclin D1 protein in 8 normal cervices and 8 invasive cancer specimens. Thirty-two cases of FIGO stage Ib-IIa cervical cancers (28 squamous cell carcinomas, 3 adenocarcinomas, 1 adenosquamous cell carcinoma), 31 cases of cervical intraepithelial neoplasia 3 (CIN 3), and 28 normal cervices were stained for cyclin D1 and p21(WAF1/CIP1) using monoclonal antibody. Statistical analysis was performed to assess the differences in expression and their prognostic significance. RESULTS. Cyclin D1 mRNA was found to be underexpressed in cervical cancer. Western blot also revealed underexpression of cyclin D1 protein in cervical cancer compared to normal controls. Positive immunohistochemical staining of cyclin D1 was noted in 28/28 (100%) of the normal controls, 1/31 (3%) cases of CIN 3, and 9/32 (28%) cases of invasive cancer. The number of positively stained specimens was lower than that of normal controls in CIN 3 and cervical cancer specimens (P = 0.005). Fifteen of 28 (54%) normal controls, 15/31 cases (48%) of CIN 3, and 27/32 cases (84%) of invasive cancer were proved positive for p21WAF1/CIP1 immunohistochemistry. p21WAF1/CIP1 was more highly expressed in cervical cancer than in that of either normal controls or CIN specimens (P = 0.001). Positive immunostaining of cyclin D1 and p21WAF1/CIP1 was not related to high-risk factors (pelvic lymph node metastasis, deep cervical stromal invasion, parametrial invasion, large tumor size, and unusual histologic type) and human papilloma virus infection. Positive cyclin D1 immunostaining was associated with decreased disease-free survival and a lower overall survival (P = 0.0175 and 0.0189, respectively). On multivariate analysis, positive cyclin D1 expression was a significant prognostic variable for recurrence (P = 0.0004). CONCLUSION: Underexpression of cyclin D1 was regulated at the level of transcription in cervical cancer. Although cyclin D1 was underexpressed in cervical neoplasias, it was more frequently expressed in malignant lesions. p21WAF1/CIP1 was more highly expressed in cervical cancers than in either normal cervices or CIN 3 specimens. Unfavorable prognoses were associated with cyclin D1 expression, and not with the expression of its inhibitor, p21WAF1/CIP1.We conclude that immunohistochemical assessment of cyclin D1 can be a useful molecular marker for predicting prognosis in early stage cervical cancer of the uterus.

Blotting, Northern↗