• Asian Pacific Journal of Cancer Prevention
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• v.16 no.9
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• pp.3817-3825
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• 2015

Background: The human protein methyl-transferase DOT1L catalyzes the methylation of histone H3 on lysine 79 (H3K79) at homeobox genes and is also involved in a number of significant processes ranging from gene expression to DNA-damage response and cell cycle progression. Inhibition of DOT1L activity by shRNA or small-molecule inhibitors has been established to prevent proliferation of various MLL-rearranged leukemia cells in vitro, establishing DOT1L an attractive therapeutic target for mixed lineage leukemia (MLL). Most of the drugs currently in use for the MLL treatment are reported to have low efficacy, hence this study focused on various natural compounds which exhibit minimal toxic effects and high efficacy for the target receptor. Materials and Methods: Structures of human protein methyl-transferase DOT1L and natural compound databases were downloaded from various sources. Virtual screening, molecular docking, dynamics simulation and drug likeness studies were performed for those natural compounds to evaluate and analyze their anti-cancer activity. Results: The top five screened compounds possessing good binding affinity were identified as potential high affinity inhibitors against DOT1L's active site. The top ranking molecule amongst the screened ligands had a Glide g-score of -10.940 kcal/mol and Glide e-model score of -86.011 with 5 hydrogen bonds and 12 hydrophobic contacts. This ligand's behaviour also showed consistency during the simulation of protein-ligand complex for 20000 ps, which is indicative of its stability in the receptor pocket. Conclusions: The ligand obtained out of this screening study can be considered as a potential inhibitor for DOT1L and further can be treated as a lead for the drug designing pipeline.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.17
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• pp.7091-7095
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• 2014

Background: The study aimed to evaluate the incidence of CpG island promoter methylation of BMP6, a member of the transforming growth factor beta family, in tissue samples from colorectal cancers (CRC) and look for its association with BMP6 expression and clinicopathological correlation. Materials and Methods: Methylation specific PCR for the BMP6 promoter region was performed with 85 frozen tissue samples of CRC and 45 of normal colon. Methylation status of MLH1 was also determined by the same method. Expression of BMP6 was evaluated by immunohistochemistry (IHC), using Allred's scoring system. The methylation status was analyzed against clinical and pathological parameters in CRC. Results: The study revealed BMP6 hypermethylation in 34 of 85 tumor specimens (40%), and 15 out of 45 normal tissue samples from CRC (33%). The incidence of hypermethylation was inversely correlated with IHC score. Allred's scores of 7 or more were correlated with lower frequency of BMP6 hypermethylation (29% compared to 50% in the remaining, p-value 0.049). However, there was no association between hypermethylation status and any clinicopathological parameters. The methylation status of BMP6 was not correlated with that of MLH1, a key methylation determinant in CRC. On survival analysis, there was no significant difference in progress-free survival (PFS) between the cases with and without hypermethylation (2-year PFS 74% and 76%, respectively). Conclusions: CpG island methylation of BMP6 is found in high frequency in CRC and this epigenetic event is associated with suppressed protein expression in the tumor tissue. However, the marker is not associated with tumor progression of the disease.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.18
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• pp.7563-7567
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• 2014

Background: Hepatocellular carcinoma (HCC) is the first cause of death in cirrhotic patients, mostly due to viral hepatitis with HCV or HBV infection. This study was performed to estimate the true prevalence of viral hepatitis-related HCC and the demographic and clinical-pathological associations with the two virus types. Materials and Methods: This cross sectional observational study enrolled clinical data base of 188 HCC patients and variables included from baseline were age, sex, area of residence, clinical-pathological features such as underlying co-morbidity, presence or absence of liver cirrhosis, macrovascular involvement, tumor extension and metastasis, liver lobes involved, serum alpha-fetoprotein level, and hepatitis serologies. Results: Overall prevalence of HCV- and HBV-related HCC was 66.0% and 34.0%, respectively. Patients with HCV were more likely to develop HCC at advanced age ($52.4{\pm}11.9$ vs. $40.7{\pm}12.09$ years), with highly raised serum AFP levels (${\geq}400ng/ml$) 78.2% (HBV 67.1%), large tumor size (HCV-66% >5 cm, HBV-59.3%), and presence of portal vein thrombosis (8.06%, HBV 1.56%). A binominal multivariate analysis showed that HCV-HCC group were more likely to be cirrhotic (OR=0.245, 95%CI: 0.117, 0.516) and had more than two times higher rate of solitary macrovascular involvement (OR=2.533, 95%CI: 1.162, 5.521) as compared with HBV associated HCC. Conclusions: Statistically significant variations were observed from baseline to clinical-pathological characteristics in HCV vs HBV associated HCC. Our study suggests prompt and early screening for high risk patients so that the rate of progression of these chronic viral diseases to cirrhosis and cancer can be decreased.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.11
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• pp.6475-6479
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• 2013

Objectives: Glutathione S-transferase (GST) isoenzymes play important roles in resistance to cell apoptosis and carcinogenesis. We aimed to establish the relationship between GST expression and the prognosis of upper urinary tract urothelial carcinoma (UTT-UC) in Taiwan. Methods: This study retrospectively reviewed 46 patients with pathologically confirmed UUT-UC at Kaohsiung Medical University Hospital. In each patient, expression of GSTT1 and GSTP1 was compared between urothelial carcinoma and normal urothelial cells by Western blotting. Results: GSTP1 expression in the UUT-UC cells was significantly higher than that in normal urothelial cells (1.6 fold, p<0.001). Expression of GSTT1 was significantly associated with the invasiveness of the carcinoma (p=0.006). Conclusions: In UUT-UC, GSTP1 might be a potential tumor marker, whereas high GSTT1 expression could be used as an indicator of cancer progression. This study is the first to demonstrate potential applications of different GST isoenzymes for biomolecular analysis of UUT-UCs in Taiwan.

• The Journal of Internal Korean Medicine
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• v.34 no.1
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• pp.31-45
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• 2013

Objectives : Gokgisaeng (Korean mistletoe) is used for the treatment of inflammatory and cancer diseases in traditional Korean medicine and its major component lectins have been reported to induce nitric oxide (NO) in RAW 264.7 macrophages, and also induce apoptosis of various types of cancer cells, although its modulatory effects on cancer cell migration and macrophage activation is poorly understood. The aim of this study is to clarify molecular mechanisms of action responsible for the anti-inflammatory and antitumor migration potentials of Korean mistletoe extract (KME). Methods : We investigated the anti-inflammatory activity of KME on NO production and inducible nitric oxide synthase (iNOS) expression by lipopolysaccharide (LPS) in both RAW 264.7 macrophages and rat C6 glioma cells, and also evaluated inhibitory efficacy on glioma cell growth and migration. For assessment, XTT assay, nitrite assay, RT-PCR, scratch-wound and Boyden chamber assay, and western blot analysis were performed. Results : Previously reported, unlike the efficacy of Gokgisaeng lectin, KME inhibited NO production and iNOS expression, and suppressed pro-inflammatory mediators including IL-$1{\beta}$, IL-6, COX-2, iNOS in LPS-stimulated RAW 264.7 cells. Furthermore, KME suppressed tumor cell growth and migration, and it also inhibited LPS-induced NO release and iNOS activation by down-regulating expression of protein kinase C (PKC) and phosphorylation of ERK in C6 glioma cells. Conclusions : Our research findings provide evidence that KME can play a significant role in blocking pro-inflammatory reaction and malignant progression of tumors through the suppression of NO/iNOS by down-regulating of inflammatory signaling pathways, PKC/ERK.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.8
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• pp.3537-3540
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• 2014

Background: Osteosarcomas are the most common solid malignancies of bone. In the last two decades there have been no concrete developments in their systemic treatment. In this trial we aimed to present our osteosarcoma patient clinical and demographic outcomes. Materials and Methods: Patients treated and followed up for osteosarcoma in Ankara Numune Education and Research Hospital from 2002 to 2012 were reviewed retrospectively. Results: A total of 21 patients (15 male, 6 female) were diagnosed with osteosarcoma. The disease was located at extremities in 76% and in 14% was metastatic at the time of diagnosis. Median disease free survival (DFS) was 36 months in non-metastatic patients and median progression free survival (PFS) was 2 months in metastatic patients (p<0.0001). Median overall survival (OS) was 80 months and 4 months, respectively (p=0.012). There were no survival differences in terms of presentation with pathological fracture, tumor size, tumor grade, alkaline phosphatase and lactate dehydrogenase level and type of chemotherapy regimen. Conclusions: Tumor site and stages are the most important prognostic factors for osteosarcoma. Extremity primary tumors have beter survival rates than non-extremity tumors. As a result of the use of effective chemotherapy the long term survival rates have improved from 10-20% to 60-70% in the last decades but we need more active agents, especially for metastatic cases.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.7
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• pp.3045-3050
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• 2014

Renal cell carcinoma (RCC) is the most lethal of all urological cancers and tumor angiogenesis is closely related with its growth, invasion, and metastasis. Recent studies have suggested that epidermal growth factor-like domain multiple 7 (EGFL7) is overexpressed by many tumors, such as colorectal cancer and hepatocellular carcinoma; it is also correlated with progression, metastasis, and a poor prognosis. However, the role of EGFL7 in RCC is not clear. In this study, we examined how EGFL7 contributes to the growth of RCC using a co-culture system in vitro and a xenograft model in vivo. Downregulated EGFL7 expression in RCC cells affected the migration and tubule formation of HMEC-1 cells, but not their growth and apoptosis in vitro. The level of focal adhesion kinase (FAK) phosphorylation in HMEC-1 cells decreased significantly when co-cultured with 786-0/iEGFL7 cells compared with 786-0 cells. After adding rhEGFL7, the level of FAK phosphorylation in HMEC-1 cells was significantly elevated compared with phosphate-buffered saline (PBS) control. However, FAK phosphorylation was abrogated by EGFR inhibition. The average size of RCC local tumors in the 786-0/iEGFL7 group was noticeably smaller than those in the 786-0 cell group and their vascular density was also significantly decreased. These data suggest that EGFL7 has an important function in the growth of RCC by facilitating angiogenesis.

• Journal of Yeungnam Medical Science
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• v.32 no.2
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• pp.138-142
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• 2015

L-thyroxine (LT4) withdrawal prior to radioactive iodine (RAI) ablation therapy is a commonly used method for successful treatment of patients with papillary thyroid cancer (PTC). However, a prolonged period of hypothyroidism induced by LT4 withdrawal is sometimes associated with impaired quality of life and cardiopulmonary dysfunction in PTC patients. Furthermore, LT4 withdrawal may have a trophic effect on residual cancer by means of increased thyrotropin. We report on 2 cases of metastatic PTC patients with malignant pleural effusion (MPE) whose disease showed rapid worsening after LT4 withdrawal and RAI therapy. The first case is a 65-year-old woman who had PTC with multiple distant metastases and MPE. During LT4 withdrawal for RAI therapy, MPE showed rapid worsening, and the patient required repetitive therapeutic thoracentesis. The second case is a 49-year-old woman with PTC who underwent 3 additional operations for cancer recurrence in the neck lymph nodes and 6 times of RAI treatments. While preparing for the $7^{th}$ RAI treatment by withdrawing LT4, she developed MPE which became progressively aggravated after RAI therapy. Both patients experienced increased pleural effusion during the LT4 withdrawal period and a rise in the thyroglobulin level was observed after RAI therapy. MPE was not controlled with therapeutic thoracentesis and pleurodesis. Eventually, both patients died of rapid disease progression after RAI therapy. In summary, LT4 withdrawal may have an adverse effect on metastatic PTC patients, particularly those with MPE.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.5
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• pp.2851-2857
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• 2013

Objective: REPS2 plays important roles in inhibiting cell proliferation, migration and in inducing apoptosis of cancer cells, now being identified as a useful biomarker for favorable prognosis in prostate and breast cancers. The purpose of this study was to assess REPS2 expression and to explore its role in esophageal squamous cell carcinoma (ESCC). Methods: Protein expression of REPS2 in ESCCs and adjacent non-cancerous tissues from 120 patients was analyzed by immunohistochemistry and correlated with clinicopathological parameters and patient outcome. Additionally, thirty paired ESCC tissues and four ESCC cell lines and one normal human esophageal epithelial cell line were evaluated for REPS2 mRNA and protein expression levels by quantitative RT-PCR and Western blotting. Results: REPS2 mRNA and protein expression levels were down-regulated in ESCC tissues and cell lines. Low protein levels were significantly associated with primary tumour, TNM stage, lymph node metastasis and recurrence (all, P < 0.05). Survival analysis demonstrated that decreased REPS2 expression was significantly associated with shorter overall survival and disease-free survival (both, P < 0.001), especially in early stage ESCC patients. When REPS2 expression and lymph node metastasis status were combined, patients with low REPS2 expression/lymph node (+) had both poorer overall and disease-free survival than others (both, P < 0.001). Cox multivariate regression analysis further revealed REPS2 to be an independent prognostic factor for ESCC patients. Conclusions: Our findings demonstrate that downregulation of REPS2 may contribute to malignant progression of ESCC and represent a novel prognostic marker and a potential therapeutic target for ESCC patients.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.5
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• pp.3331-3335
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• 2013

Background: The incidence of prostate cancer, one of the most common cancers in elderly men, is increasing annually in Thailand. Matrix metalloproteinase 11 (MMP-11) is a member of the extracellular matrix metalloproteases which has been associated with human tumor progression and clinical outcome. Aim: To quantify MMP-11 expression in prostatic adenocarcinoma tissues and to determine whether its overexpression correlates with survival outcome, and to assess its potential as a new prognostic marker. Materials and Methods: Expression of MMP-11 was analyzed using immunohistochemistry in 103 Thai patients with prostatic adenocarcinoma. Overall survival was analyzed using Kaplan-Meier methods and Cox regression models. Results: Immunoreactivity of MMP-11 was seen in the stroma of prostatic adenocarcinoma tissue samples, high expression being significantly correlated with poor differentiation in Gleason grading, pathologic tumor stage 4 (pT4), and positive-bone metastasis (p<0.05), but not age and prostatic-specific antigen (PSA) level. Patients with high levels of MMP-11 expression demonstrated significantly shorter survival (p<0.001) when compared to those with low levels. Multivariate analysis showed that MMP-11 expression and pT stage were related with survival in prostatic adenocarcinoma [hazard ratio (HR)=0.448, 95% confidence interval (95%CI)=0.212-0.946, HR=0.333, 95%CI=0.15-0.74, respectively]. Conclusions: Expression of MMP-11 is significantly associated with survival in prostatic adenocarcinoma. High levels may potentially be used for prediction of a poor prognosis.