• Asian Pacific Journal of Cancer Prevention
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• v.13 no.12
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• pp.6017-6022
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• 2012

Background: Resveratrol has been reported to have potential chemopreventive and apoptosis-inducing properties in a variety of tumor cell lines. Objective: In this study, to investigate the effects of resveratrol on protein kinase C (PKC) activity and apoptosis in human colon carcinoma cells, we used HT-29 cells and examined the $PKC{\alpha}$ and ERK1/2 signaling pathways. Methods: To test the effects of resveratrol on the growth of HT-29 cells, the cells were exposed to varying concentrations and assessed with the the MTT cell-viability assay. Fluorescence-activated cell sorter (FACS) analysis was applieded to determine the effects of resveratrol on cell apoptosis. Western blotting was performed to determine the protein levels of $PKC{\alpha}$ and ERK1/2. In inhibition experiments, HT-29 cells were treated with G$\ddot{o}$6976 or PD98059 for 30 min, followed by exposure to $200{\mu}M$ resveratrol for 72 h. Results: Resveratrol had a significant inhibitory effect on HT-29 cell growth. FACS revealed that resveratrol induced apoptosis. Western blotting showed that e phosphorylation of $PKC{\alpha}$ and ERK1/2 was significantly increased in response to resveratrol treatment. Pre-treatment with $PKC{\alpha}$ and ERK1/2 inhibitors (G$\ddot{o}$6976 and PD98059) promoted apoptosis. Conclusion: Resveratrol has significant anti-proliferative effects on the colon cancer cell line HT-29. The PKC-ERK1/2 signaling pathway can partially mediate resveratrol-induced apoptosis of HT-29 cells.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.12
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• pp.6357-6362
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• 2012

Background: To determine the prevalence of mammalian target of rapamycin phosphorylation (p-mTOR) and vascular endothelial growth factor (VEGF) and any correlation with clinical characteristics and prognosis in ovarian clear cell carcinoma patients. Materials and Method: Seventy four paraffin-embedded specimens of such carcinomas frompatients who underwent surgery, received adjuvant chemotherapy and were followed up at King Chulalongkorn Memorial Hospital during January 2002 to December 2008 were stained with rabbit monoclonal IgG p-mTOR and rabbit polyclonal IgG VEGF using immunohistochemical methods. Medical records were reviewed and clinical variables were analysed. Results: The prevalence of positive p-mTOR in ovarian clear cell carcinoma was 87.9% and significantly higher in advance-stage than early-stage patients (100% versus 83.6%, P<0.05). Two-year disease free survival and 2-year overall survival in patients with positive p-mTOR expression were 60% and 69.2% with no differences from patients with negative p-mTOR expression (p>0.05). The prevalence of VEGF expression was 63.5% and significantly higher in chemo-sensitive than chemo-resistant patients (70.7% versus 37.5%, P<0.05). Two-year disease free survival and 2-year overall survival in patients with VEGF expression were 72.3% and 83% respectively which were significantly different from patients with negative VEGF expression (p<0.05). Conclusions: p-mTOR expression in ovarian clear cell carcinoma was significantly correlated with the stage of disease. VEGF expression was significantly correlated with chemosensitivity, and survival. Further studies of related targeted therapy might be promising.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.8
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• pp.3653-3656
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• 2012

Background: A number of effective prevention measures have been introduced in attempts to substantially reduce both the incidence and mortality due to many kinds of cancer. The search for new anti-cancer compounds in foods or in plant medicines is one realistic and promising approach to prevention. Chinese medicines provide a rich pool of novel and efficacious agents for cancer prevention and treatment. Previously it was demonstratrated that hyperin extracted from the Manchurian rhododendron leaf reduces the proliferation of many cancer cells. The present study was carried out to evaluate its effects on human endometrial cancer cell viability and apoptosis and to investigate its mechanisms of action in RL952 cells. Methods: Cell viability was measured using the MTT assay. Intracellular calcium ions were detected using laser-scanning confocal microscopy. The effects of hyperin on apoptosis related proteins in RL952 cells were examined using Western blot analysis. Results: The growth of RL952 cells was inhibited by treatment with hyperin. OD values of caspase-3 and caspase-9 were increased and expression of bcl-2 was increased and bax was decreased in protein levels in RL952 cells after 24 h of hyperin treatment, Moreover, intracellular calcium accumulation occurred in hyperin-treated cells. Conclusion: These results suggest that hyperin may play an important role in tumor growth suppression by inducing apoptosis in human endometrial cells via a $Ca^{2+}$-related mitochondrion apoptotic pathway in RL952 cells.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.17
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• pp.7129-7135
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• 2014

Background: In this study, we aimed to evaluate the growth inhibitory effect of the combination of ethaselen (BBSKE) and low fixed dose of selenite against A549 human non-small cell lung cancer cells in vitro. Materials and Methods: Growth inhibitory effects against A549 cells were determined by SRB assay. Combination index (CI) values were calculated based on Chou-Talalay median-effect analyses. Dose reduction index (DRI) values were applied to calculate dose reduction of selenite. Contents of free thiols and GSH were determined by DTNB assay and intracellular ROS levels by DCFH-DA fluorescence labeling. Results: Compared with BBSKE or selenite single treatment, the combined application of ethaselen and a low fixed dose of selenite shortened the onset time of sodium selenite, reduced $IC_{50}$ values, and increased the maximum inhibition rates, suggesting a possible molecular mechanism of the synergism. Obvious synergistic effects were observed after different times of combination treatment, especially after 24 h. Compared with selenite single treatment, dosage of selenite could be remarkably reduced in combination therapy to gain the same inhibitory effect on cell proliferation. Compared with BBSKE single treatment, the content of free thiols and GSH were significantly reduced and ROS levels greatly elevated in the combination group. For the combination treatment, cell viability increased as greater concentrations of GSH were added. Conclusions: All these results indicate that the combination treatment of BBSKE and selenite showed synergism to inhibit A549 cell proliferation in vitro, and also reduced the selenite dosage to mitigate its toxicity which is very meaningful for combination chemotherapy of lung cancer. The synergism was probably caused by the accelerated exhaustion of intracellular reductive substances, such as free thiols and GSH, which ultimately leads to enhanced oxidative stress and apoptosis.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.18
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• pp.7799-7803
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• 2014

Background: To determine the imprinting status of the IGF2 in Chinese patients with primary lung cancer and to analyze the clinical significance of the loss of imprinting (LOI) of IGF2. Materials and Methods: PCRRFLP and RT-PCR-RFLP were carried out to select heterozygous cases for the ApaI polymorphism within exon 9 of the IGF2 gene and further analyze IGF2 LOI in 64 lung cancer patients, respectively. Results: Of 64 lung cancer patients, 31 were heterozygous for IGF2. The positive rates of IGF2 LOI of lung cancer foci, matched paracancer tissues, and normal lung tissues were 77.4% (24/31), 61.3% (19/31), and 29.0% (9/31), respectively. The LOI differences for IGF2 among the three groups were statistically significant (${\chi}^2=15.267$, p=0.000), and the LOI frequency of IGF2 in normal lung tissue was significantly lower than that in lung cancer foci and paracancer tissues (${\chi}^2=14.577$, p=0.000; ${\chi}^2=6.513$, p=0.011). No statistical difference was observed between the lung tumor group and the matched paracancer group (${\chi}^2=1.897$, p=0.168). The prevalence of advanced clinical stages (${\chi}^2=2.379$; p=0.017) and lymph node metastasis (${\chi}^2=5.552$; p=0.018) was significantly higher for LOI-positive paracancer tissues than for LOI-negative paracancer tissues. Conclusions: IGF2 LOI is highly frequent in Chinese primary lung cancer patients, especially those with increased risk of lymph node metastasis and advanced clinical stages. IGF2 LOI may be an early epigenetic event in human lung carcinogenesis.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.11
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• pp.6681-6686
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• 2013

Background: Fatal adverse events (FAEs) have been reported with sorafenib, a vascular endothelial growth factor receptor kinase inhibitor (VEGFR TKI). We here performed an up-to-date and detailed meta-analysis to determine the overall risk of FAEs associated with sorafenib. Methods: Databases, including PubMed, Embase and Web of Science, and abstracts presented at the American Society of Clinical Oncology annual meetings were searched to identify relevant studies. Eligible studies included randomized controlled trials evaluating sorafenib effects in patients with all malignancies. Summary incidence rates, relative risks (RRs), and 95% confidence intervals (CIs) were calculated for FAEs. In addition, subgroup analyses were performed according to tumor type and therapy regimen. Results: 13 trials recruiting 5,546 patients were included in our analysis. The overall incidence of FAEs with sorafenib was 1.99% (95%CI, 0.98-4.02%). Patients treated with sorafenib had a significantly increased risk of FAEs compared with patients treated with control medication, with an RR of 1.77 (95%CI 1.25-2.52, P=0.001). Risk varied with tumour type, but appeared independent of therapy regimen. A significantly increased risk of FAEs was observed in patients with lung cancer (RR 2.26; 95% CI 1.03-4.99; P= 0.043) and renal cancer (RR 1.84; 95% CI 1.15-2.94; P= 0.011). The most common causes of FAEs were hemorrhage (8.6%) and thrombus or embolism (4.9%). Conclusions: It is important for health care practitioners to be aware of the risks of FAEs associated with sorafenib, especially in patients with renal and lung cancer.

• Journal of Ginseng Research
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• v.40 no.2
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• pp.151-159
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• 2016

Background: Ginsenoside-Rg3, the pharmacologically active component of red ginseng, has been found to inhibit tumor growth, invasion, metastasis, and angiogenesis in various cancer models. Previously, we found that 20(R)-ginsenoside-Rg3 (Rg3) could inhibit angiogenesis. Since microRNAs (miRNAs) have been shown to affect many biological processes, they might play an important role in ginsenoside-mediated angiomodulation. Methods: In this study, we examined the underlying mechanisms of Rg3-induced angiosuppression through modulating the miRNA expression. In the miRNA-expression profiling analysis, six miRNAs and three miRNAs were found to be up- or down-regulated in vascular-endothelial-growth-factor-induced human-umbilical-vein endothelial cells (HUVECs) after Rg3 treatment, respectively. Results: A computational prediction suggested that mature hsa-miR-520h (miR-520h) targets ephrin receptor (Eph) B2 and EphB4, and hence, affecting angiogenesis. The up-regulation of miR-520h after Rg3 treatment was validated by quantitative real-time polymerase chain reaction, while the protein expressions of EphB2 and EphB4 were found to decrease, respectively. The mimics and inhibitors of miR- 520h were transfected into HUVECs and injected into zebra-fish embryos. The results showed that overexpression of miR-520h could significantly suppress the EphB2 and EphB4 protein expression, proliferation, and tubulogenesis of HUVECs, and the subintestinal-vessel formation of the zebra fish. Conclusion: These results might provide further information on the mechanism of Rg3-induced angiosuppression and the involvement of miRNAs in angiogenesis.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.1
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• pp.97-101
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• 2015

Background: The gene for the vascular endothelial growth factor (VEGF), which promotes angiogenesis and permeability, is polymorphic. The aim of the present study was to evaluate the relationship between +936C>T and +404C>G polymorphism of VEGF with risk of esophageal cancer in the Kashmiri population in India. Materials and Methods: 150 esophageal cancer patients and 150 unrelated healthy controls were genotyped for two VGEF SNPs (+405C/G, and +936C/T) using DNA extracted from prospectively collected blood samples by the PCR-RFLP method. Results: For the VEGF +936C>T polymorphism a significant association of CT and combined CT+TT genotypes was observed with increased risk of esophageal cancer (p=0.021; 0.024). For the +405C>G polymorphism we observed significantly increased frequency of GG genotype in cases as compared to controls and also the +405 GG Genotype was observed to have a two fold risk(OR=2.7356; 95%CI=1.1409-6.5593; p=0.020). The combined genotypes of GG-CC and GG-CT of +405C>G and +936C>T were found to be significantly associated with increased risk of esophageal cancer (p=0.0376; 0.0099). Conclusions: From the results of the present study a significant association of +936C>T and +405C>G polymorphisms with increased esophageal cancer risk exists in the Kashmiri population.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.1
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• pp.271-274
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• 2015

Background: To explore vascular endothelial growth factor C (VEGF-C) and VEGF-D expression and its correlation with lymph node metastasis in esophageal squamous cell cancer (ESCC) tissue. Materials and Methods: Immunohistochemical methods were applied to detect the levels of VEGF-C and VEGF-D expression in 64 surgicall removal ESCC tissues, tissues adjacent to cancer and normal tissues, and the relationship between VEGF-C and VEGF-D expression and lymph node metastasis was analyzed. Results: Both VEGF-C and VEGF-D were expressed by varying degrees in esophageal cancer tissue, the tissue adjacent to cancer and normal tissue, and the positive expression rate went down successively. The positive expression rates of VEGF-C (59.4%) and VEGF-D (43.8%) in esophageal cancer tissue were significantly higher than in the tissue adjacent to cancer (34.4%, 15.6%) and normal tissue (20.3%, 12.5%), respectively, in which significant differences were manifested (p<0.01). Positive expression rates of VEGF-C and VEGF-D in esophageal cancers with lymph node metastasis were markedly higher than without such metastasis (p<0.01), while those in the tissue with TNM staging I~II were markedly lower than that with TNM staging III~IV (p<0.01). Conclusions: Both VEGF-C and VEGF-D are highly expressed in ESCC tissue, which may be related to the lymph node metastasis of cancer cells. Hence, VEGF-C and VEGF-D can be clinically considered as important reference indexes of lymph node metastasis in esophageal cancer.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.7
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• pp.3471-3476
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• 2012

Background and Objective: Histone deacetylase (HDAC) inhibitors represent a promising class of potential anticancer agents for treatment of human malignancies. In this study, we investigated the effect of trichostatin A (TSA), one such HDAC inhibitor, in combination with docetaxel (TXT), a cytotoxic chemotherapy agent or erlotinib, a novel molecular target therapy drug, on lung cancer A549 cells. Methods: A549 cells were treated with TXT, erlotinib alone or in combination with TSA, respectively. Cell viability, apoptosis, and cell cycle distribution were evaluated using MTT (3- (4, 5-dimethylthiazol-2-yl) -2, 5-diphenyltetrazolium bromide) assay, Hochst33258 staining and flow cytometry. Moreover, immunofluorescent staining and Western blot analysis were employed to examine alterations of ${\alpha}$-tubulin, heat shock protein 90 (hsp90), epidermal growth factor receptor (EGFR), and caspase-3 in response to the different exogenous stimuli. Results: Compared with single-agent treatment, co-treatment of A549 cells with TSA/TXT or TSA/erlotinib synergistically inhibited cell proliferation, induced apoptosis, and caused cell cycle delay at the $G_2/M$ transition. Treatment with TSA/TXT or TSA/erlotinib led to a significant increase of cleaved caspase-3 expression, also resulting in elevated acetylation of ${\alpha}$-tubulin or hsp90 and decreased expression of EGFR, which was negatively associated with the level of acetylated hsp90. Conclusions: Synergistic anti-tumor effects are observed between TXT or erlotinib and TSA on lung cancer cells. Such combinations may provide a more effective strategy for treating human lung cancer.