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ABSTRACT: This study aimed at examining the association of gene silencing and promoter methylation of glutathione peroxidase 1 (GPX1) and glutathione peroxidase 3 (GPX3) in gastric cancer cells and determined the clinical significance of GPX1 and GPX3 expression loss in gastric cancer tissue.
Analysis of mRNA expression was carried out by reverse transcription-polymerase chain reaction (RT-PCR). Methylation of the GPX1 promoter region was analyzed by bisulfite sequencing, and that of the GPX3 promoter region was analyzed by methylation-specific PCR (MSP). Tissue microarray-based immunohistochemistry of GPX1 and GPX3 in 1,163 resected gastric cancer specimens was performed to assess the associations with clinicopathological parameters.
Reduced GPX1 and GPX3 mRNA expression was associated with promoter methylation in gastric cancer cell lines. A correlation between DNA promoter methylation and loss of GPX1 expression was noted in 16 gastric cancer tissue samples (p=0.005). Loss of GPX1 and GPX3 proteins was found in 24.4% and 30.8% of gastric cancer tissues. Loss of GPX1 expression was significantly associated with advanced gastric cancer (p=0.039) and lymphatic invasion (p=0.010); loss of GPX3 expression was associated with advanced gastric cancer (p<0.001) and lymph node metastasis (p<0.001). Kaplan-Meier analysis showed that low expression of GPX1 was associated with poor cancer-specific survival (p=0.010).
Data from this study implicate aberrant hypermethylation of promoter regions of GPX1 and GPX3 as a mechanism for down-regulation of GPX1 and GPX3 mRNA expression in gastric cancer cells. Loss of GPX1 expression was associated with aggressiveness and poor survival in patients with gastric cancer.
Anticancer research 08/2012; 32(8):3169-75. · 1.73 Impact Factor
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ABSTRACT: Fibroblast growth factor receptor 2 is a member of receptor tyrosine kinase family, and fibroblast growth factor receptor 2 gene amplification or missense mutation has been observed in various human cancers, including gastric carcinoma. Recent studies have shown that anti-fibroblast growth factor receptor 2 agents inhibit tumor progression in various human cancers, such as endometrial carcinoma and gastric carcinoma, which remains one of the most frequent causes of cancer-related death worldwide. We considered that knowledge of the status of fibroblast growth factor receptor 2 gene amplification in gastric carcinoma might aid in targeted cancer therapy. In this study, fibroblast growth factor receptor 2 amplification status was evaluated by fluorescence in situ hybridization in 313 surgically resected gastric carcinoma tissues, and the results were validated by quantitative real-time polymerase chain reaction. In addition, potential associations between clinicopathologic parameters and the presence of fibroblast growth factor receptor 2 amplification were investigated, and survival analysis was performed. Of the 313 cases, 14 (4.5%) showed fibroblast growth factor receptor 2 amplification by fluorescence in situ hybridization. Fibroblast growth factor receptor 2 amplification was found to be associated with a higher pT stage (P = .023), higher pN stage (P = .038), and distant metastasis (P = .009) and to be significantly associated with lower cancer-specific survival by univariate analysis (P = .012). Gastric carcinoma with fibroblast growth factor receptor 2 amplification was found to be associated with advanced disease and a poor prognosis. We believe that the determination of fibroblast growth factor receptor 2 amplification status could allow the identification of a subset of cancers sensitive to targeted fibroblast growth factor receptor 2 inhibitor-based therapy.
Human pathology 03/2012; 43(10):1559-66. · 3.03 Impact Factor
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ABSTRACT: Mucoepidermoid carcinoma of the bile duct is an extremely rare tumor. Seventeen cases originating from intrahepatic bile duct and 2 cases from common hepatic duct have been reported in the English literature. Mucoepidermoid carcinoma arising from the common bile duct has not been previously reported. A 68 year-old man was admitted due to obstructive jaundice. Computed tomography showed a malignant tumor of the common bile duct located in the intrapancreatic segment. Filling defects of the distal common bile duct was seen on endoscopic retrograde cholangiogram. Under the impression of bile duct cancer, pylorus-preserving pancreatoduodenectomy was performed. Histologic diagnosis of the resected specimen was mucoepidermoid carcinoma of the common bile duct. After surgery, the patient received concurrent chemoradiotherapy, and planned to receive additional chemotherapy. We herein report on a first case of primary mucoepidermoid carcinoma of the common bile duct, and review the literature.
The Korean journal of gastroenterology = Taehan Sohwagi Hakhoe chi 05/2011; 57(5):319-22.
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ABSTRACT: The early B-cell factors (EBFs) are a group of four highly conserved DNA-binding transcription factors with an atypical zinc-finger and a helix-loop-helix domain. The EBF3 locus on chromosome 10q26.3 is epigenetically silenced or deleted in several types of cancers. In addition, EBF3 activates genes involved in cell cycle arrest and inhibits cell survival. However, inactivation of EBF3 gene expression was not fully studied in gastric carcinoma and the functions of EBF3 that underlie EBF3-regulated tumor suppression have not been identified. In our study, we found that inactivation of the EBF3 gene is frequently accompanied by promoter region hypermethylation in several gastric cancer cell lines and that the gene is reactivated by 5-aza-2'-deoxycytidine (5-aza-dc) and/or trichostatin A (TSA) in all ten gastric cancer cell lines. We performed functional analysis using small interfering RNA or expressional cDNA transfection in gastric cancer cell lines and demonstrate that EBF3 represses gastric cancer cell growth and migration, but activates cell cycle arrest and apoptosis. Promoter methylation of EBF3 was detected in 42/104 (40.4%) gastric cancer tissues but not in normal gastric tissues. Furthermore, promoter methylation of EBF3 was found to be significantly correlated with lymphatic invasion (p = 0.013) and poor survival (p = 0.038) in gastric carcinoma. These results suggest that EBF3 tumor suppressor is epigenetically silenced and that it serves as an independent prognostic marker in gastric carcinoma.
International Journal of Cancer 03/2011; 130(4):817-26. · 5.44 Impact Factor
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ABSTRACT: The methylthioadenosine phosphorylase (MTAP) gene is located on 9p21 telomeric to the CDKN2A tumor suppressor gene. Loss of MTAP gene is frequently associated with CDKN2A homozygous deletion. Although the homozygous deletion of MTAP has been reported in various human cancers, its function in gastric carcinogenesis is unknown. Here, we determined the status of the MTAP gene by using a combination of array-based comparative genomic hybridization and oligonucleotide microarray. It was found that MTAP was deleted and downregulated in 2 of 10 gastric cancer cell lines. Of the 494 primary gastric carcinomas examined, MTAP expression at the protein level was reduced in 59 (11.9%). Furthermore, a lack of MTAP expression was found to be associated with poor survival (P = 0.038). The genomic loss of MTAP and CDKN2A in gastric carcinomas was investigated by quantitative real-time PCR. Among 20 gastric carcinomas, two cases showed deletion of both MTAP and CDKN2A, and three samples showed homozygous deletion of MTAP, but not of CDKN2A. An analysis of gastric carcinomas revealed that reduced MTAP expression correlated significantly with a genomic deletion. Furthermore, functional assays by transfecting the siRNA or the expressional cDNA into gastric cancer cell lines demonstrated that MTAP regulates cell growth and invasion. The present study suggests that MTAP plays an important role in the regulation of gastric carcinogenesis and, in particular, that MTAP loss is implicated in some way with tumor growth via the modulation of cellular properties, which, in turn, suggests that MTAP has therapeutic applications.
Genes Chromosomes and Cancer 03/2011; 50(6):421-33. · 3.31 Impact Factor
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Keun Su Son,
Han-Sung Kang,
Sun Jung Kim,
So-Youn Jung, Sun Young Min,
See Youn Lee,
Seok Won Kim,
Youngmee Kwon,
Keun Seok Lee,
Kyung Hwan Shin,
Jungsil Ro
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ABSTRACT: The purpose of the study was to evaluate the methylation status of the interleukin-10 (IL-10) gene in breast cancer tissues compared with normal and benign breast disease tissues. Between 2000 and 2001, we used paraffin-embedded specimens of 30 normal, 31 benign and 72 breast cancer tissues from the National Cancer Center, Korea. The methylation patterns of the IL-10 gene were evaluated using bisulfite DNA sequencing and the expression levels of IL-10 mRNA were evaluated using real-time reverse transcriptase-polymerase chain reaction (qRT-PCR) and reverse transcriptase-polymerase chain reaction (RT-PCR). The methylation rates of the IL-10 gene were significantly lower in malignant tumors than in benign and normal tissues (normal; 63.3%, benign; 74.2%, cancer; 45.8%, p = 0.02). The methylation density rates of the IL-10 gene were also significantly lower in malignant tumors (normal; 59.68 ± 7.12%, benign; 48.89 ± 7.45%, cancer; 30.56 ± 4.18%, p = 0.001). Tissues with aberrant methylation of the IL-10 gene showed significantly lower rates of mRNA expression compared with unmethylated cases (12.5% vs. 68.0%, p = 0.012). The mRNA expression of tissues with unmethylated IL-10 was upregulated approximately ten thousand-fold compared to those with IL-10 methylation in the real-time RT-PCR experiment. IL-10 methylation demonstrated a significant association with lower expression of Ki-67 (9.36 ± 2.43 vs. 19.68 ± 3.42, p = 0.02). IL-10 methylation in cancer tissues is lower than that in normal and benign breast tissues, and DNA hypomethylation in the gene influences gene activation. Our data suggest that hypomethylation of the IL-10 gene can be involved in the process of breast carcinogenesis.
Breast (Edinburgh, Scotland) 12/2010; 19(6):484-8. · 2.09 Impact Factor
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Sun Young Min,
Seung Ju Lee,
Kyung Hwan Shin,
In Hae Park,
So-Youn Jung,
Keun Seok Lee,
Jungsil Ro,
Seeyoun Lee,
Seok Won Kim,
Tae Hyun Kim,
Han-Sung Kang,
Kwan Ho Cho
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ABSTRACT: Breast conservation surgery (BCS) and radiotherapy (RT) following neoadjuvant chemotherapy (NCT) have been linked with high locoregional recurrence (LRR) rates and ipsilateral breast tumor recurrence (IBTR) rates. The purpose of this study was to analyze clinical outcomes in patients who exhibited LRR and IBTR after being treated by BCS and RT following NCT.
In total, 251 breast cancer patients treated with BCS and RT following NCT between 2001 and 2006 were included. All patients had been shown to be clinically node-positive. Clinical stage at diagnosis (2003 AJCC) was II in 68% of patients and III in 32% of patients. Of those, 50%, 35%, and 15% of patients received anthracycline-based, taxane-based, and combined anthracycline-taxane NCT, respectively. All patients received RT.
During follow-up (median, 55 months), 26 (10%) patients had LRR, 19 of these patients had IBTR. Five-year actuarial rates of IBTR-free and LRR-free survival were 91% and 89%, respectively. In multivariate analyses, lack of hormone suppression therapy was found to increase both LRR and IBTR rates. Hazard ratios were 7.99 (p<0.0001) and 4.22 (p=0.004), respectively. Additionally, pathology stage N2 to N3 increased LRR rate (hazard ratio, 4.22; p=0.004), and clinical AJCC stage III IBTR rate (hazard ratio, 9.05; p=0.034). Achievement of pathological complete response and presence of multifocal tumors did not affect LRR or IBTR.
In patients with locally advanced disease, who were clinically node-positive at presentation, BCS after NCT resulted in acceptably low rates of IBTR and LRR. Mastectomy should be considered as an option in patients who present with clinical stage III tumors or who are not treated with adjuvant hormone suppression therapy, because they exhibit high IBTR rates after NCT and BCS.
International journal of radiation oncology, biology, physics 12/2010; 81(5):e697-705. · 4.59 Impact Factor
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ABSTRACT: The biological mechanisms underlying resistance to tamoxifen are of considerable clinical significance. However, little is known about the correlation between tamoxifen resistance and methylation of genes related to drug-metabolizing enzymes. To address this issue, we examined the methylation pattern and expression of the selected genes coding for drug-metabolizing enzymes, including COMT, CYP1A1, CYP2D6, NAT1, and SULT1A1 in tamoxifen-resistant and control breast cancers. Bisulfite genomic sequencing and methylation-specific PCR were carried out to evaluate the methylation patterns of the five genes from control (n = 74) and tamoxifen-resistant tissues (n = 37) chosen by an age-matched sampling method. Also, end-point reverse transcriptase polymerase chain reaction (RT-PCR) and real-time RT-PCR were performed to determine RNA expression of the genes. Bisulfite genomic sequencing revealed methylation of the NAT1 gene in 25 of the control cancers (33.8%) and 23 of the resistant tumors (62.2%). Of the five genes, only NAT1 showed a significant lower methylation rate in the control group than in the resistant group (p = 0.004). No significant difference of the methylation rate was found in the other four genes including COMT, CYP1A1, CYP2D6, and SULT1A1 (p > 0.05). Furthermore, the expression rate of NAT1 mRNA was lower in the tumors from the resistant group than in control tumors (28.6% vs. 65.2%, p = 0.031). Real-time RT-PCR analysis demonstrated that the NAT1 gene was more down-regulated in resistant tissues than in control group (p = 0.023). Moreover, malignant cells from the resistant cases demonstrated a higher percentage of positive staining for Ki67 (p = 0.001) and cyclin D1 (p = 0.043) than those from the control group. Taken together, the higher methylation rate of the NAT1 gene is related to tamoxifen resistance, and this fact supports the hypothesis that hypermethylation of the NAT1 gene might affect the initiation of tamoxifen resistance.
Journal of Molecular Medicine 11/2010; 88(11):1123-31. · 4.67 Impact Factor
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ABSTRACT: This study was conducted to mine novel breast-specific unigenes and analyze their epigenetic regulation in breast cancer. Differential digital display and methylation analysis identified the Hs.137007 gene containing a Kelch domain as a candidate novel epigenetic marker. In 50 pairs of breast cancer tissues and nearby normal tissues the methylation level of the 14 CpG sites at the promoter region (-778 to -485) of the gene was higher in cancer tissues (72-93%) than in normal tissues (31-83%), with a high correlation rate (p<0.05). End-point RT-PCR and real-time RT-PCR revealed that Hs.137007 was up-regulated in cancer tissues. A clear relationship between high methylation levels and up-regulated expression was also observed in the cultured breast cell lines. The MCF7 (90-100%) and MDAMB468 (100%) cancer cell lines that showed higher methylation than the BT549 (20-90%) and 184B5 (10-100%) at the 14 CpGs also showed elevated gene expression. Taken together, these results indicate that the Hs.137007 gene is a novel gene specifically expressed in the breast that can be utilized as an epigenetic marker of breast cancer.
International Journal of Oncology 05/2010; 36(5):1105-11. · 2.40 Impact Factor
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So-Youn Jung,
Hyun Yul Kim,
Byung-Ho Nam, Sun Young Min,
Seung Ju Lee,
Chansung Park,
Youngmee Kwon,
Eun-A Kim,
Kyoung Lan Ko,
Kyung Hwan Shin,
Keun Seok Lee,
In Hae Park,
Seeyoun Lee,
Seok Won Kim,
Han-Sung Kang,
Jungsil Ro
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ABSTRACT: The present study was designed to assess the clinical characteristics and outcomes of metaplastic breast cancer (MBC) compared to general invasive ductal carcinoma (IDC) and the triple-negative subtype (TN-IDC). The study population included 35 MBC and 2,839 IDC patients, including 473 TN-IDC diagnoses, from the National Cancer Center, Korea between 2001 and 2008. The clinicopathological characteristics and clinical outcomes were retrospectively reviewed. Mean age of patients was 47.4 years for the MBC group and 48.3 years for the IDC group. The MBC patients presented with a larger tumor size (>/=T2, 74.3% vs. 38.8%, P < 0.001), more distant metastasis at the first diagnosis (8.6% vs. 2.0%, P = 0.04), higher histologic grade (grade 3, 65.7% vs. 41.4%, P < 0.001), fewer estrogen receptor (ER), and progesterone receptor (PgR) positivity (ER+, 5.7% vs. 65.4%, P < 0.001; PgR+, 8.6% vs. 55.8%, P < 0.001), higher Ki-67 expression (35.5 +/- 26.2% vs. 20.6 +/- 19.8%, P = 0.024), and more TN subtypes (80.0% vs. 16.7%, P < 0.001) compared to the IDC group. Fifteen (46.8%) MBC patients and 260 (9.3%) IDC patients experienced disease recurrence with a median follow-up of 47.2 months (range 4.9-100.6 months). MBC was a poor prognostic factor for disease recurrence and overall survival in univariate and multivariate analysis (HR 3.89 in recurrence, 95% CI: 1.36-11.14, P = 0.01; HR 5.29 in death, 95% CI: 2.15-13.01, P < 0.001). MBC patients also experienced more disease recurrence (HR 3.99, 95% CI: 1.31-12.19, P = 0.01) and poorer overall survival (HR 3.14, 95% CI: 1.19-8.29, P = 0.02) compared to the 473 TN-IDC patients, as reflected by aggressive pathological features. Patients with MBC appeared to have inherently aggressive tumor biology with poorer clinical outcomes than those with general IDC or TN-IDC.
Breast Cancer Research and Treatment 02/2010; 120(3):627-37. · 4.43 Impact Factor
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ABSTRACT: Pylephlebitis, a rare complication of acute appendicitis, is defined as thrombophlebitis of the portal venous system. Pylephlebitis usually occurs due to secondary infection in the region drained into the portal system. We report a case of pylephlebitis caused by acute appendicitis. The patient was transferred from a private clinic 1 wk after appendectomy with the chief complaints of high fever and abdominal pain. He was diagnosed with pylephlebitis of the portal vein and superior mesenteric vein by CT-scan. The patient was treated with antibiotics and anticoagulation therapy, and discharged on the 25th day and follow-up CT scan showed a cavernous transformation of portal thrombosis.
World Journal of Gastroenterology 08/2008; 14(28):4580-2. · 2.47 Impact Factor
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ABSTRACT: To investigate the structure-activity relationships of 3-arylisoquinolines, diverse substituted 3-aryisoquinolinamines were synthesized and tested in vitro antitumor activity against four tumor cell lines. Some of the compounds showed potent topoisomerase I inhibitory activity. Docking study of 7d with topoisomerase I-DNA complex was also performed.
Bioorganic & Medicinal Chemistry Letters 01/2004; 13(24):4451-4. · 2.55 Impact Factor
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ABSTRACT: A series of 43 stilbene derivatives that showed cytotoxicity against human lung carcinoma (A549) was analyzed using comparative molecular field analysis (CoMFA) for defining the hypothetic pharmacophore model. The polyoxylated stilbenes were found to be active inhibitors of tubulin polymerization. Several cis-stilbenes are structurally similar to combretastatins. However, the trans-stilbenes are assumed to be close to resveratrol found in grapes and have been reported to be potential cancer chemopreventive agents by modulating the initiation, promotion, and progression of the carcinogenic process. With several synthesized compounds that were evaluated for antitumor cytotoxicity against human lung tumor cells (A549), the stilbene derivatives were subjected to CoMFA. To perform systematic molecular modeling of these compounds, a conformational search was carried out based on the precise dihedral angle analysis of the lead compound (1p). The X-ray crystallographic structure of combretastatin A-1 was also used for defining the active conformers of the compounds. After determining the energy-minimized conformers of the lead compound (1p), CoMFA was performed using five different alignments. The three dimensional (3D)-quantitative structure-activity relationship study resulted in reasonable cross-validated, conventional r(2) values equal to 0.640 and 0.958, respectively.
CHEMICAL & PHARMACEUTICAL BULLETIN 06/2003; 51(5):516-21. · 1.59 Impact Factor
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ABSTRACT: To determine the quality of life (QoL) of breast cancer patients who underwent mastectomy and immediate breast reconstruction with a latissimus dorsi myocutaneous flap (LD), and the oncological safety of the procedure. Between May 2001 and March 2007, 2,566 patients had breast cancer surgery at the National Cancer Center, Korea. Of the 2,566 patients, 1,699 had breast-conserving surgery (BCS) and 120 had a mastectomy with an immediate LD. We retrospectively compared the oncologic safety of the two techniques. We also assessed the QoL using the EORTC QLQ BR-23 and Zung's self-rating depression scale in 52 LD patients, 104 age- and stage-matched patients who underwent BCS, and 104 age-matched healthy women. The LD group had earlier stage disease than the BCS group at baseline, but following surgery, the groups did not differ in the rates of local recurrence or systemic metastases. Compared with the healthy group, the patient groups had poorer functioning and more depression (p < 0.001). Among the patient groups, the LD group reported lower scores for body image (p = 0.007) and future perspective (p = 0.023) than the BCS group. In the LD group, patients who received neoadjuvant chemotherapy reported lower scores for future perspective and higher scores for depression than those who did not receive neoadjuvant chemotherapy (p < 0.001). The BCS and LD groups did not differ in oncological outcome, and the QoL of patients in the LD group was not always good. Mastectomy with immediate reconstruction should be considered carefully and tailored to the patient's needs and characteristics.
The Breast Journal 16(4):356-61. · 1.64 Impact Factor
