• Journal of Gastric Cancer
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• v.10 no.4
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• pp.155-161
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• 2010

Purpose: The purpose of this study was to investigate the reliability and the clinical applicability of the adenosine-triphosphate-based chemotherapy response assay (ATP-CRA) as a method of determining in vitro chemosensitivity in patients with gastric cancer. Materials and Methods: A total of 243 gastric cancer tissue samples were obtained from gastrectomies performed between February 2007 and January 2010. We evaluated the effectiveness of the ATP-CRA assay in determining the chemosensitivity of gastric cancer specimens using eleven chemotherapeutic agents - etoposide, doxorubicin, epirubicin, mytomicin, 5-fluorouracil, oxaliplatin, irinotecan, docetaxel, paclitaxel, methotraxate, and cisplatin - for chemosensitivity studies using ATP-CRA. We assessed the failure rate, the cell death rate, and the chemosensitivity index. Results: The failure rate of ATP-CRA was 1.6% (4/243). The mean coefficient of variation for triplicate ATP measurements was 6.5%. Etoposide showed the highest cell death rate (35.9%) while methotrexate showed the lowest (16.6%). The most active chemotherapeutic agent was etoposide, which most frequently ranked highest in the chemosensitivity test: 31.9% (51/160). Oxaliplatin was more active against early gastric cancers than advanced gastric cancers, whereas docetaxel was more active against advanced cancers. The lymph node negative group showed a significantly higher cell death rate than the lymph node positive group when treated with doxorubicin, epirubicin, and mitomycin. Conclusions: ATP-CRA is a stable and clinically applicable in vitro chemosensitivity test with a low failure rate. The clinical usefulness of ATP-CRA should be evaluated by prospective studies comparing the regimen guided by ATP-CRA with an empirical regimen.

• Radiation Oncology Journal
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• v.36 no.4
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• pp.325-331
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• 2018

Purpose: Soft tissue sarcoma (STS) is a rare and heterogeneous cancer with over 50 known subtypes. It is difficult to understand the role of adjuvant treatment in STS. We aimed to determine the benefits of adjuvant treatment for a rare STS subset: non-extremity STS with moderate chemosensitivity. Materials and Methods: We reviewed medical records from Pusan National University Hospital and Kosin University Gospel Hospital, which had detailed pathological reports on patients diagnosed between 2006 and 2016. The most important inclusion criterion was resection with curative intent. We grouped STS by chemosensitivity based on reported data and analyzed non-extremity STS with moderate chemosensitivity. Results: We investigated 142 patients with 20 pathological subtypes of STS. Eighty-six patients had extremity STS and 56 had non-extremity STS. Thirty-eight of 56 patients were categorized as having moderate chemosensitivity. Seventeen of 38 patients (44.7%) received adjuvant radiotherapy and 14 (36.8%) received adjuvant chemotherapy. A log-rank test showed longer disease-free survival (DFS) in the adjuvant radiotherapy group than in the group treated without adjuvant radiotherapy (not reached vs. 1.468 years, p = 0.037). Multivariate Cox proportional hazard analysis, with covariates including age, stage, resection margin, adjuvant chemotherapy, and adjuvant radiotherapy, revealed that adjuvant radiotherapy was associated with longer DFS (odds ratio = 0.369, p = 0.045). Overall survival was not correlated with adjuvant radiotherapy. Conclusion: Adjuvant radiotherapy may be associated with longer DFS in patients with non-extremity STS with moderate chemosensitivity.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.4
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• pp.1425-1430
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• 2012

Cyclin L2 is a novel member of the cyclin family, recently implicated in the regulation of cell cycle progression and/or transcriptional regulation. The present study was undertaken to investigate the effects of overexpression on tumor cell growth and chemosensitivity in human gastric cells in vitro. Cyclin L2 was transfected into human gastric cancer cell line BCG823 and expressed with a mammalian expression vector pcDNA3.1. The effects and mechanisms of cyclin L2 on cell growth, cell cycling and apoptosis were studied. Compared to control vectors, overexpression of cyclin L2 inhibited the growth of BCG823 cells and enhance their chemosensitivity to fluorouracil, docetaxel and cisplatin. The anti-proliferative effects of cyclin L2 could be due to G0/G1 arrest and apoptosis. Cyclin L2 induced G0/G1 arrest and apoptosis involved upregulation of caspase-3 and down regulation Bcl-2 and survivin. The results indicated that overexpression of cyclin L2 protein may promote efficient growth inhibition and enhance chemosensitivity to chemotherapeutic agents in human gastric cancer cells by inducing G0/G1 cell cycle arrest and apoptosis.

• Journal of Gastric Cancer
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• v.20 no.1
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• pp.95-105
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• 2020

Purpose: Gastric cancer is a highly metastatic malignant tumor, often characterized by chemoresistance and high mortality. In the present study, we aimed to investigate the role of B-cell lymphoma 3 (Bcl-3) protein on cell migration and chemosensitivity of gastric cancer. Materials and Methods: The gastric cancer cell lines, AGS and NCI-N87, were used for the in vitro studies and the in vivo studies were performed using BALB/c nude mice. Western blotting, wound healing assay, Cell Counting Kit-8 assay, immunohistochemistry, and terminal deoxynucleotidyl transferase dUTP nick end labeling assay were used to evaluate the role of Bcl-3 in gastric cancer. Results: We found that the protein expression of hypoxia (HYP)-inducible factor-1α and Bcl-3 were markedly upregulated under hypoxic conditions in both AGS and NCI-N87 cells in a time-dependent manner. Interestingly, small interfering RNA-mediated knockdown of Bcl-3 expression affected the migration and chemosensitivity of the gastric cancer cells. AGS and NCI-N87 cells transfected with si-RNA-Bcl-3 (si-Bcl-3) showed significantly reduced migratory ability and increased chemosensitivity to oxaliplatin, 5-fluorouracil, and irinotecan. In addition, si-Bcl-3 restored the autophagy induced by HYP. Further, the protective role of si-Bcl-3 on the gastric cancer cells could be reversed by the autophagy inducer, rapamycin. Importantly, the in vivo xenograft tumor experiments showed similar results. Conclusions: Our present study reveals that Bcl-3 knockdown inhibits cell migration and chemoresistance of gastric cancer cells through restoring HYP-induced autophagy.

• Archives of Pharmacal Research
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• v.19 no.4
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• pp.261-263
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• 1996

SK-302B, an antibiotic purified from soil Streptomyces sp. 302, was structurally identified as echinomycin (C/sub 50/H/sub 66/N/sub 11/S/sub 2/). In the present experiment, the possibility of SK-302B as an anticolon cancer agent was investigated by using chemosensitivity system (MTT assay, clonogenic assay). Treatment of SK-302B on various colon cancer cell lines resulted in a significant cytotoxicity and tumor colony formation inhibition. These studies showed that SK-302B had a potent inhibition on colon cancer cells.

• Nutrition Research and Practice
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• v.14 no.2
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• pp.95-101
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• 2020

BACKGROUND/OBJECTIVES: Folate plays a critical role in DNA synthesis and methylation. Intracellular folate homeostasis is maintained by the enzymes folylpolyglutamate synthase (FPGS) and γ-glutamyl hydrolase (GGH). FPGS adds glutamate residues to folate upon its entry into the cell through a process known as polyglutamylation to enhance folate retention in the cell and to maintain a steady supply of utilizable folate derivatives for folate-dependent enzyme reactions. Thereafter, GGH catalyzes the hydrolysis of polyglutamylated folate into monoglutamylated folate, which can subsequently be exported from the cell. The objective of this review is to summarize the scientific evidence available on the effects of intracellular folate homeostasis-associated enzymes on cancer chemotherapy. METHODS: This review discusses the effects of FPGS and GGH on chemosensitivity to cancer chemotherapeutic agents such as antifolates, such as methotrexate, and 5-fluorouracil. RESULTS AND DISCUSSION: Polyglutamylated (anti)folates are better substrates for intracellular folate-dependent enzymes and retained for longer within cells. In addition to polyglutamylation of (anti)folates, FPGS and GGH modulate intracellular folate concentrations, which are an important determinant of chemosensitivity of cancer cells toward chemotherapeutic agents. Therefore, FPGS and GGH affect chemosensitivity to antifolates and 5-fluorouracil by altering intracellular retention status of antifolates and folate cofactors such as 5,10-methylenetetrahydrofolate, subsequently influencing the cytotoxic effects of 5-fluorouracil, respectively. Generally, high FPGS and/or low GGH activity is associated with increased chemosensitivity of cancer cells to methotrexate and 5-fluorouracil, while low FPGS and/or high GGH activity seems to correspond to resistance to these drugs. Further preclinical and clinical studies elucidating the pharmocogenetic ramifications of these enzyme-induced changes are warranted to provide a framework for developing rational, effective, safe, and customized chemotherapeutic practices.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.5
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• pp.3057-3062
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• 2013

Background: Selecting chemotherapy regimens guided by chemosensitivity tests can provide individualized therapies for cancer patients. The 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2Htetrazolium, inner salt (MTS) assay is one in vitro assay which has become widely used to evaluate the sensitivity to anticancer agents. The aim of this study was to evaluate the clinical applicability and accuracy of MTS assay for predicting chemotherapeutic response in unresectable NSCLC patients. Methods: Cancer cells were isolated from malignant pleural effusions of patients by density gradient centrifugation, and their sensitivity to eight chemotherapeutic agents was examined by MTS assay and compared with clinical response. Results: A total of 37 patients participated in this study, and MTS assay produced results successfully in 34 patients (91.9%). The sensitivity rates ranged from 8.8% to 88.2%. Twenty-four of 34 patients who received chemotherapy were evaluated for in vitro-in vivo response analysis. The correlation between in vitro chemosensitivity result and in vivo response was highly significant (P=0.003), and the total predictive accuracy, sensitivity, specificity, positive predictive value, and negative predictive value for MTS assay were 87.5%, 94.1%, 71.4%, 88.9%, and 83.3%, respectively. The in vitro sensitivity for CDDP also showed a significant correlation with in vivo response (P=0.018, r=0.522). Conclusion: MTS assay is a preferable in vitro chemosensitivity assay that could be use to predict the response to chemotherapy and select the appropriate chemotherapy regimens for unresectable NSCLC patients, which could greatly improve therapeutic efficacy and reduce unnecessary adverse effects.

• Journal of Korean Neurosurgical Society
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• v.50 no.5
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• pp.426-433
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• 2011

Objective : The Histoculture Drug Response Assay (HDRA), which measures chemosensitivity using minced tumor tissue on drug-soaked gelfoam, has been expected to overcome the limitations of in vitro chemosensitivity test in part. We analyzed interim results of HDRA in malignant gliomas to see if the test can deserve further clinical trials. Methods : Thirty-three patients with malignant gliomas were operated and their tumor samples were examined for the chemosensitivity to 10 chosen drugs by HDRA. The most sensitive chemotherapy regimen among those pre-established was chosen based on the number of sensitive drugs or total inhibition rate (IR) of the regimen. The response was evaluated by 3 month magnetic resonance image. Results : Among 13 patients who underwent total resection of the tumor, 12 showed no evidence of disease and one patient revealed progression. The response rate in 20 patients with residual tumors was 55% (3 complete and 8 partial responses). HDRA sensitivity at the cut-off value of more than one sensitive drug in the applied regimen showed a sensitivity of 100%, specificity of 60% and predictability of 70%. Another cut-off value of >80% of total IR revealed a sensitivity of 100%, specificity of 69%, and predictability of 80%. For 12 newly diagnosed glioblastoma patients, median progression-free survival of the HDRA sensitive group was 21 months, while that of the non-sensitive group was 6 months ($p$=0.07). Conclusion : HDRA for malignant glioma was inferred as a feasible method to predict the chemotherapy response. We are encouraged to launch phase 2 clinical trial with chemosensitivity on HDRA.

• Journal of Gastric Cancer
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• v.7 no.3
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• pp.160-166
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• 2007

Purpose: Recently, chemosensitivity tests have become widely used for the selection of effective drugs in gastric cancer patients. In this study, a chemosensitivity test was performed to select agents to increase the effectiveness of adjuvant chemotherapy. Materials and Methods: Chemosensitivity testing was performed in 81 gastric cancer patients that received a gastrectomy at the Yeungnam University Hospital. An ATP (adenosine triphosphate) based chemotherapy response assay was used. Clinicopatholgical factors such as sex, age, expression of tumor markers (CEA and CA19-9 levels), location of the tumor, morphology of advanced cancer, histological type, cell differentiation, depth of invasion, Lauren classification, Ming classification, lymphatic invasion, vascular invasion, neural invasion, lymph node metastasis and TNM stage were used to correlate the chemosensitivity and clinicopathological factors. Results: The most effective antitumor agents in gastric cancer patients were (in order of effectiveness) 5-FU, Epirubicin, lrinotecan and Oxaliplatin in our series. The chemosensitivity test showed a significant difference in susceptibility according to clinicopathological factors. Conclusion: Further studies on multidrug therapy are needed to evaluate synergistic effects of drugs. Therefore, for effective chemotherapy, it is more efficacious to select a chemosensitive drug than continue to use the same drug regimen.

• Asian-Australasian Journal of Animal Sciences
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• v.2 no.3
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• pp.151-153
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• 1989