Akter, Hafeza;Yoon, Jung Hwan;Yoo, Young Sook;Kang, Min-Jung
Molecules and Cells
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v.41
no.6
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pp.591-602
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2018
Gastric cancer is the fifth most common type of malignancy worldwide, and the survival rate of patients with advanced-stage gastric cancer is low, even after receiving chemotherapy. Here, we validated neurotensin receptor 1 (NTSR1) as a potential therapeutic target in gastric cancer. We compared NTSR1 expression levels in sixty different gastric cancer-tissue samples and cells, as well as in other cancer cells (lung, breast, pancreatic, and colon), by assessing NTSR1 expression via semi-quantitative real-time reverse transcription polymerase chain reaction, immunocytochemistry and western blot. Following neurotensin (NT) treatment, we analyzed the expression and activity of matrix metalloproteinase-9 (MMP-9) and further determined the effects on cell migration and invasion via wound-healing and transwell assays. Our results revealed that NTSR1 mRNA levels were higher in gastric cancer tissues than non-cancerous tissues. Both of NTSR1 mRNA levels and expression were higher in gastric cancer cell lines relative to levels observed in other cancer-cell lines. Moreover, NT treatment induced MMP-9 expression and activity in all cancer cell lines, which was significantly decreased following treatment with the NTSR1 antagonist SR48692 or small-interfering RNA targeting NTSR1. Furthermore, NT-mediated metastases was confirmed by observing epithelial-mesenchymal transition markers SNAIL and E-cadherin in gastric cancer cells. NT-mediated invasion and migration of gastric cancer cells were reduced by NTSR1 depletion through the Erk signaling. These findings strongly suggested that NTR1 constitutes a potential therapeutic target for the inhibition of gastric cancer invasion and metastasis.
The rhizome extract of Atractylodes japonica Koidzumi(Compositae) exhibited a particular inhibition on the proliferation of cultured human tumor cell lines, in vitro. Thus, the intensive phytichemical investigation of the MeOH extract of Atractylodes japonica have been conducted by the way of activity-guided purification. The repeated column chromatographic separation of the n-hexane soluble part of extract resulted in the isolation of four sesquiterpenes (1-4) and a polyacetylene component (5). Chemical structures of them were identified as atractylon (1), atractylenolide Ⅰ(2), atractylenolide Ⅲ(3), eudesma-4(15),7(11)-dien-8-one (4) and 1,3-diacetyl-atractylodiol (5) by spectroscopic means. Among the isolates, compound 2-4 were shown to give moderate inhibitory effect in a dose dependent manner on the proliferation of cultured human tumor cell lines such as A549 (non small cell lung), SK-OV-3 (ovary), SK-MEL-2 (melanoma), XF498 (central nerve system) and HCT 15(colon), respectively.
Background : Tumor necrosis factor(TNF) has been considered as an important candidate for cancer gene therapy based on its potent anti-tumor activity. However, since the efficiency of current techniques of gene transfer is not satisfactory, the majority of current protocols is aiming the in vitro gene transfer to cancer cells and re-introducing genetically modified cancer cells to host. In the previous study, it was shown that TNF-sensitive cancer cells transfected with TNF-$\alpha$ cDNA would become highly resistant to TNF, and the probability was shown that the acquired resistance to TNF might be associated with synthesis of some protective protein. Understanding the mechanisms of TNF -resistance in TNF-$\alpha$ cDNA transfected cancer cells would be. an important step for improving the efficacy of cancer gene therapy as well as for better understandings of tumor biology. This study was designed to evaluate the role of MnSOD, an antioxidant enzyme, in the acquired resistance to TNF of TNF-$\alpha$ cDN A transfected cancer cells. Method : We transfected TNF-$\alpha$ c-DNA to WEHI164(murine fibrosarcoma cell line), NCI-H2058(human mesothelioma cell line), A549(human non-small cell lung cancer cell line), ME180(human cervix cancer cell line) cells using retroviral vector(pLT12SN(TNF)) and confirm the expression of TNF with PCR, ELISA, MIT assay. Then we determined the TNF resistance of TNF-$\alpha$ cDNA transfected cells(WEHI164-TNF, NCIH2058-TNF, A549-TNF, ME180-TNF) and the changes of MnSOD mRNA expressions with Northern blot analysis. Results : The MnSOD mRNA expressions of parental cells and genetically modified cells of WEHI164 and ME180 cells(both are naturally TNF sensitive) were not significantly different The MnSOD mRNA expressions of genetically modified cells of NCI-H2058 and A549(both are naturally TNF resistant) were higher than those of the parental cells, while those of parental cells with exogenous TNF were also elevated. Conclusion : The acquired resistance to TNF after TNF-$\alpha$ cDNA transfection may not be associated with the change in the MnSOD expression, but the difference in natural TNF sensitivity of each cell may be associated with the level of the MnSOD expression.
The induction of apoptosis in target cells is a key mechanism for most anti-tumor therapies. Bufalin is a cardiotonic steroid that has the potential to induce differentiation and apoptosis of tumor cells. Research on bufalin has so far mainly involved leukemia, prostate cancer, gastric cancer and liver cancer, and has been confined to in vitro studies. The bufadienolides bufalin and cinobufagin have been shown to induce apoptosis in a wide spectrum of cancer cell. The present article reviews the anticancer effects of bufalin. It induces apoptosis of lung cancer cells via the PI3K/Akt pathway and also suppressed the proliferation of human non-small cell lung cancer A549 cell line in a time and dose dependent manner. Bufalin, bufotalin and gamabufotalin, key bufadienolides, significantly sensitize human breast cancer cells with differing ER-alpha status to apoptosis induction by the TNF-related apoptosis-inducing ligand (TRAIL). In addition, bufadienolides induce prostate cancer cell apoptosis more significantly than that in breast epithelial cell lines. Similar effects have been observed with hepatocellular carcinoma (HCC) but the detailed molecular mechanisms of inducing apoptosis in this case are still unclear. Bufalin exerts profound effects on leukemia therapy in vitro. Results of multiple studies indicate that bufalin has marked anti-tumor activities through its ability to induce apoptosis. Large-scale randomized, double-blind, placebo or positive drug parallel controlled studies are now required to confirm the efficacy and apoptosis-inducing potential of bufalin in various cancers in the cliniucal setting.
Background: We performed this study to identify the tumor suppressor genes located in the long arm of chromosome 21 in non-small cell lung cancer. Material and Method: The genes of USP25 in 21q11.2, NCAM2, ADAMTS1 in 21q21.2, and Claudin-8 (CLDN8), Claudin-17 (CLDN17) and TIAM1 in 21q22.1 were investigated for their gene expressions, genetic alterations and promoter methylation. Result: The expressions of CLDN8 and CLDN17 were significantly decreased in 7 (L132, H157, H358, H522, H1299, H1703 and HCC2108) of 13 cell lines, and the expression of ADAMTS1 was also significantly reduced in 6 cell lines (A549, SW900, H1299, H1373, H1703 and H1793). There were no genetic alterations by PCR-SSCP and cDNA cloning in the cell lines with a decreased gene. In the cell lines with a decreased gene expression, the mRNA expression was increased significantly with treatment of 5-Aza-CdR. Conclusion: These results suggest that the ADMTS1, CLDN8 and CLDN17 may act as tumor suppressor genes.
Ulasli, Sevinc Sarinc;Celik, Sefa;Gunay, Ersin;Ozdemir, Mehmet;Hazman, Omer;Ozyurek, Arzu;Koyuncu, Tulay;Unlu, Mehmet
Asian Pacific Journal of Cancer Prevention
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v.14
no.10
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pp.6159-6164
/
2013
Background: Phytochemical compounds are emerging as a new generation of anticancer agents with limited toxicity in cancer patients. The purpose of this study was to investigate the potential effcts of thymoquinone, caffeic acid phenylester (CAPE) and resveratrol on inflammatory markers, oxidative stress parameters, mRNA expression levels of proteins and survival of lung cancer cells in Vitro. Materials and Methods: The A549 cell line was treated with benzo(a)pyrene, benzo(a)pyrene plus caffeic acid phenylester (CAPE), benzo(a)pyrene plus resveratrol (RES), and benzo(a)pyrene plus thymoquinone (TQ). Inflammatory markers, oxidative stress parameters, mRNA expression levels of apoptotic and anti-apoptotic proteins and cell viability were assessed and results were compared among study groups. Results: TQ treatment up-regulated Bax and down-regulated Bcl2 proteins and increased the Bax/Bcl2 ratio. CAPE and TQ also up-regulated Bax expression. RES and TQ down-regulated the expression of Bcl-2. All three agents decreased the expression of cyclin D and increased the expression of p21. However, the most significant up-regulation of p21 expression was observed in TQ treated cells. CAPE, RES and TQ up-regulated TRAIL receptor 1 and 2 expression. RES and TQ down-regulated the expression of NF-kappa B and IKK1. Viability of CAPE, RES and TQ treated cells was found to be significantly decreased when compared with the control group (p=0.004). Conclusions: Our results revealed up-regulation of the key upstream signaling factors, which ultimately cause increase in their regulatory p53 levels affecting the induction of G2/M cell cycle arrest and apoptosis. Overall these results provide mechanistic insights for understanding the molecular basis and utility of the anti-tumor activity of TQ, RES and CAPE.
Kim, Mi Kyeong;Moon, Dong Chul;Hyun, Hye Jin;Kim, Jong-Sik;Choi, Tae Jin;Jung, Sang Bong
Journal of Life Science
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v.26
no.9
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pp.1056-1062
/
2016
Lung cancer is currently the most common malignant disease and the leading cause of mortality in the world and non-small cell lung cancer (NSCLC) accounts for 75-80% of lung cancer cases. miR-155 gene was found to be over expressed in several solid tumors, such as thyroid carcinoma, breast cancer, colon cancer, cervical cancer, pancreatic ductal adenocarcinoma (PDAC) and lung cancer. The aims of this study were to define the expression of miR-155 in lung cancer and its associated clinic-pathologic characteristics. Total RNA was purified from formalin-fixed, paraffin-embedded NSCLC tissues and benign lung tissues. Expression of miR-155 in human lung cancer tissues were evaluated as mean fold changes of miR-155 in cancer tissues compared to benign lung tissues by quantitative real-time reverse transcriptase polymerase chain reaction (real-time qRT-PCR) and associations of miR-155 expression with clinic-pathologic findings of cancer. Compared with the benign control group, miR-155 expression was significantly overexpressed in NSCLCs (p=<0.001). miR-155 was more overexpressed in squamous cell carcinoma than in adenocarcinoma. Poorly differentiated tumors showed significantly overexpression of miR-155 than well-differentiated tumors (p=<0.001). Overexpression of miR-155 was significantly associated with lymph node metastasis (p=<0.05). In survival analysis for all NSCLC patients, high miR-155 expression was significantly correlated with worse overall survival (p=<0.05). These results suggested that miR-155 might play an important role in lung cancer progression and metastasis.
Backgroud : MUC1 mucin is a heavily glycosylated large glycoprotein and is expressed aberrantly in carcinoma. CD44 is polymorphic family of cell surface glycoproteins participating in cell-cell adhesion and modulation of the cell-matrix interaction. MUC1 mucin and CD44 expression have been implicated in a tumor invasion and metastasis in certain malignancies. In this study, the expression of MUC1 and the standard form of CD44 (CD44s) was examined in non-small cell lung cancer (NSCLC). Methods : Immunohistochemical staining using monoclonal antibodies including MUC1 glycoprotein and CD44s was performed on 80 NSCLC surgical specimens. The association between MUC1 and CD44s expression and the histological type and tumor stage was investigated. Results : Depolarized MUC1 expression in more than 10% of cancer cells was found in 12 (27.9%) out of 43 squamous cell carcinomas (SCCs) and 12 (32.4%) out of 37 adenocarcinomas (ACs). It was not associated with the tumor histological type and the TNM-stage in SCCs. Depolarized MUC1 expression correlated with the N-stage in ACs (p=0.036). CD44s was expressed in 36 (83.7%) out of 43 SCCs and 14 (37.8%) out of 37 ACs. Reduced CD44s expression correlated with the N-stage (p=0.031) and the TNM-stage (p=0.006) in SCCs. Conclusions : Depolarized MUC1 expression was related to the nodal stage in NSCLC adenocarcinoma. Reduced CD44s expression was related to nodal involvement and the TNM-stage in squamous cell carcinoma. This suggests that MUC1 and CD44s expression in NSCLC might play important roles in tumor progression and cap be used as prognostic variables.
Background: TRAIL is a promising anticancer agent which induces selective tumor cell death due to a unique receptor system that includes death receptors and decoy receptors. DR5 TRAIL receptor is an originally identified p53-regulated death receptor gene that was induced, by doxorubicine, only in cells with a wild-type p53 status. We investigated that focused on the correlation between the DR5 and p53 expressions in non-small cell lung cancer (NSCLC). Methods: Immunohistochemical analysis, with using avidin-biotinylated horseradish peroxidase complex, was carried out in 89 surgically resected NSCLC formalin-fixed paraffin-embedded tissue sections. As primary antibodies, we used anti-DR5 polyclonal antibody and anti-p53 monoclonal antibody. A negative control was processed with each slide. The positive tumor cells were quantified twice and these values were expressed as percentage of the total number of tumor cells, and the intensity of immunostaining was expressed. The analysis of the DR5 expression was done separately in tumor area and in a nearby region of normal tissue. Results: The DR5 expression was high in the bronchial epithelium (89% of cases) but this was almost absent in type I & II pneumocytes, lymphocytes and smooth muscle cells. High DR5 expression rate in tumor was seen in 28% (15/53) of squamous cell carcinomas, in 47% (15/32) of adenocarcinomas and, in 50% (2/4) of large cell carcinomas. The DR5 expression did not show any statistical significance relationship with the T stage, N stage, or survival. However, the DR5 expression showed significant inverse correlation with the p53 expression. (p< 0.01). Conclusion: We demonstrated that the DR5 expression in NSCLC via immunohistochemical analysis is relatively tumor-specific except for that in the normal bronchial epithelium and it is significantly dependent on the p53 status. This might be in vivo evidence for the significance of the DR5 gene as a p53 downstream gene.
Background: The XRCC1 (X-ray repair cross complimenting group-I) gene in BER (base excision repair) pathway is essential for DNA repair process. Polymorphisms in this gene are associated with variations in the repair efficiency which might predispose individuals to development of various cancers. Two variants of XRCC1gene (at codon 399), Gln/Gln and Arg/Gln, have been shown to be related to lowered DNA repair capacity and increased genomic instability in multiple studies. Hence our investigation focused on genotyping these variants to correlate with other multiple risk factors in lung cancer (NSCLC) patients since we hypothesized that these variants of the XRCC1 gene might influence disease susceptibility. Materials and Methods: We examined the frequency of the polymorphism in one hundred cases and an almost equal number of controls after recording their demographics with a structured questionnaire. Genomic DNA from blood samples was extracted for PCR studies, followed by RFLP to determine the variants. The significance of the data was statistically analyzed. Results: The three genotypes in cases and controls were Arg/Arg (40% and 54.45%); Gln/Gln (19% and 9.90%), and Arg/Gln (41.0% and 35.64%) respectively. Among these 3 genotypes, we found Gln/Gln and Arg/Gln to show association with lung cancer. Correlating these genotypes with several parameters, we also found that these two variants were associated with risk in males (p<0.05) and with smoking habits (p<0.05). In females Arg/Gln genotype showed association with stage of the disease (p=0.04). This is the first report in South Indian scenario where Arg399Gln genotypes were found to be associated with stage of the disease in females. Conclusions: It is concluded that XRCC1 genotypes Gln/Gln and Arg/Gln may influence cancer susceptibility in patients with smoking habits and these functional SNPs in XRCC1 gene may act as attractive candidate biomarkers in lung cancer for diagnosis and prognosis.
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