• Journal of Life Science
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• v.16 no.5
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• pp.828-833
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• 2006

Maize (Zea mays L.) pistil cell death and stamen cell arrest are pivotal process on the sex determination, which diverges from bisexual state of floral meristem to unisexual state in staminate or pistillate floret. We investigated the temporal and spatial distribution of cell cycle gene expression during maize sex determination. The positive regulatory genes of cell cycle, cyclin A, cyclin B, cyclin dependent kinase (CDK) and Mad2 were highly expressed in the developing pistil and stamen but the expression was disappeared in the dying pistil and arresting stamens. In contrast, the negative regulatory genes of cell cycle, Wee1 and CDK inhibitor (CKI) were expressed in the arresting stamens in the wild-type ear and tasselseed2 mutant tassel, however, these genes were not detected in dying pistil although the cyclin B gene expression was disappeared. These results suggest that both the pistil cell death and stamen cell arrest process in maize sex determination are involved in cell cycle regulation, but the different expression patterns of negative regulatory cell cycle genes in the arresting stamens and aborting pistils suggest that the two processes may have distinctive modes of action.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.12
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• pp.5189-5193
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• 2016

Objective: Dorema glabrum Fisch. & C.A. Mey is a perennial plant that has several curative properties. Anti-proliferative activity of seeds of this plant has been demonstrated in a mouse fibrosarcoma cell line. The aim of the present study was to evaluate cytotoxicity of D. glabrum root extracts in a human gastric adenocarcinoma (AGS) cell line and explore mechanisms of apoptosis induction, cell cycle arrest and altered gene expression in cancer cells. Materials and Methods: The MTT assay was used to evaluate IC50 values, EB/AO staining to analyze the mode of cell death, and flow cytometry to assess the cell cycle. Quantitative real-time polymerase chain reaction (qRT-PCR) amplification was performed with apoptosis and cell cycle-related gene primers, for cyclin D1, c-myc, survivin, VEGF, Bcl-2, Bax, and caspase-3 to determine alteration of gene expression. Results: Our results showed that n-hexane and chloroform extracts had greatest toxic effects on gastric cancer cells with IC50 values of $6.4{\mu}g/ml$ and $4.6{\mu}g/ml$, respectively, after 72 h. Cell cycle analysis revealed that the population of treated cells in the G1 phase was increased in comparison to controls. Cellular morphological changes indicated induction of apoptosis. In addition, mRNA expression levels of Bax and caspase-3 were increased, and of bcl-2 survivin, VEGF, c-myc and cyclin D1 were decreased. Conclusion: Our study results suggest that D. glabrum has cytotoxic effects on AGS cells, characterized by enhanced apoptosis, reduced cell viability and arrest of cell cycling.

• Molecular & Cellular Toxicology
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• v.2 no.3
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• pp.159-165
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• 2006

To determine the anticancer effect of D-amygdalin (D-mandelinitrole-${\beta}$-D-gentiobioside) in human chronic myeloid leukemia cells K562, we profiled the gene expression between amygdalin treatment and control groups. Through 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay, the cytotoxicity of D-amygdalin was $57.79{\pm}1.83%$ at the concentration of 5 mg/mL for 24 h. We performed cDNA microarray analysis and compared the gene expression profiles between D-amygdalin (5 mg/mL, 24 h) treatment and control groups. Among the genes changed by D-amygdalin, we paid attention to cell cycle-related genes, and particularly cell cycle regulator genes; because arrest of cell cycle processing was ideal tactic in remedy for cancer. In our data, expressions of cyclin-dependent kinase inhibitor 1B (p27, Kip1) (CDKN1B), ataxia telangiectasia mutated (includes complementation groups A, C, and D) (ATM), cyclin-dependent kinase inhibitor 1C (p57, Kip2) (CDKN1C), and CHK1 checkpoint homolog (CHEK1, formally known as CHK1) were increased, while expressions of cyclin-dependent kinase 2 (CDK2), cell division cycle 25A (CDC25A), and cyclin E1 (CCNE1) were decreased. The pattern of these gene expressions were confirmed through RT-PCR. Our results showed that D-amygdalin might control cell cycle regulator genes and arrest S phase of cell cycle in K562 cells as the useful anticancer drug.

• Toxicological Research
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• v.20 no.2
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• pp.109-116
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• 2004

For the safety evaluation of adenovirus-mediated gene transfer, we investigated differential gene expressions after transfecting adenoviral vector containing p16 tumor suppressor gene (Ad5CMV-p16) into human non-small cell lung cancer cells. In the previous study, we showed adenovirus-mediated $p16^{INK4a}$ gene transfer resulted in significant inhibition of cancer cell growth. We investigated gene expression changes after transfecting Ad5CMV-p16, Ad5CMV (null type, a mock vector) into A549 cells by using cDNA chip and oligonucleotide microarray chip (1200 genes) which carries genes related with signal transduction pathways, cell cycle regulations, oncogenes and tumor suppressor genes. We found that $p16^{INK4a}$ gene transfer down regulated 5 genes (cdc2, cyclin D3, cyclin B, cyclin E, cdk2) among 26 genes involved in cell cycle regulations. Compared with serum-free medium treated cells, Ad5CMV-p16 changed 27 gene expressions, two fold or more on oligonucleotide chip. In addition, Ad5CMV-p16 did not seem to increase the tumorigenicity-related gene expression in A549 cells. Further studies will be needed to investigate the effect of Ad5CMV-p16 on normal human cells and tissues for safety evaluation.

• The Journal of Korean Obstetrics and Gynecology
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• v.18 no.1
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• pp.169-180
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• 2005

Objective : Spatholobus Suberectus Dunn stems, Chinese vine plants, have been used for the relief of menstrual disorders and rheumatic arthralgia. In this study, we investigated the antitumor effect of Spatholobus Suberectus Dunn on cervical cancer in vitro. Methods : HeLA cervical cancer cell lines were used as targets. We examined the effect of water extract from Spatholobus Suberectus Dunn on cell proliferation, cell cycle regulation and cell cycle-regulating gene expression. Further, we investigated the apoptotic effects of Spatholobus Suberectus Dunn on cervical cancer cell lines. Results : Spatholobus Suberectus Dunn significantly inhibited the proliferation of cervical cancer cell lines in a dose-dependent and time dependent manner. Fluorescence activated cell sorter (FACS) analysis indicated that Spatholobus Suberectus Dunn induced G1 cell cycle arrest. Spatholobus Suberectus Dunn enhanced the expression of $p21^{waf1}$ and $p27^{kip1}$ with cell cycle arrest. Further, Spatholobus Suberectus Dunn stimulated apoptosis via caspase3 pathway. Conclusions : These findings suggest that Spatholobus Suberectus Dunn is a candidate agent for the treatment of cervical cancer. p21waf1 and $p21^{waf1}$ and $p27^{kip1}$ may play an important role in Spatholobus Suberectus Dunn-induced cell cycle arrest and cell growth inhibition.

• The Journal of Internal Korean Medicine
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• v.26 no.1
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• pp.60-73
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• 2005

Objectives : The aim of this study was to evaluate the effects of Loranthus parasiticus Merr. on cell cycle and expression of related genes in HepG2 cells. Methods : The MTT assay, cell counting assay, $[^3H]-Thymidine$ incorporation assay, flow cytometric analysis, quantitative RT-PCR and western blot assay were studied. Results : In the water extract of Loranthus parasiticus Merr., inhibition of cell proliferation and DNA synthesis in HepG2 cells was seen. These inhibitory effects were due to inhibition of G l-S transition in cell cycle. After treatment with the extract, expression of cyclin D1(G1 check point related gene) was inhibited particularly in dose-dependent and time-dependent manners. Conclusion : These results suggest that the inhibition of cell cycle progression by Loranthus parasiticus Merr. in HepG2 cell is due to suppression of cyclin D1(G1 check point related gene) mRNA expression and protein synthesis.

• The Journal of Korean Obstetrics and Gynecology
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• v.19 no.3
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• pp.1-12
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• 2006

Purpose : This study was aimed to investigate the inhibitory effect of Leonurus sibiricus on the proliferation of human uterine leiomyoma cells and the expression of gene related the mechanism of cell apoptosis. Methods : We counted the number of death cells treated with indicated concentration of Leonurus sibiricus and investigated cell death rate by MTS assay. Furthermore, flow cytometry analysis and DNA fragmentation assay were used to dissect between necrosis and apoptosis and then we observed the differential gene expression by western blot analysis. Results : Leonurus sibiricus significantly inhibited the proliferation of uterine leiomyoma cell in a dose-dependent and time dependent manner. Fluorescence activated cell sorter (FACS) analysis indicated that Leonurus sibiricus induced G1 cell cycle arrest. Leonurus sibiricus enhanced the expression of p27 and p53 with cell cycle arrest. Conclusion : These findings suggest that Leonurus sibiricus is a candidate agent for the treatment of uterine leiomyoma. p27, $p53^{1}$ may play an important role in Leonurus sibiricus-induced cell cycle arrest and cell growth inhibition.

• Tuberculosis and Respiratory Diseases
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• v.44 no.4
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• pp.796-805
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• 1997

Background : It is clear that deregulation of cell cycle progression is a hallmark of neoplastic transformation and genes involved in the $G_1$/S transition of the cell cycle are especially frequent targets for mutations in human cancers, including lung cancer. p16 gene product, one of the G1 cell-cycle related proteins, that is recently identified plays an important role in the negative regulation of the the kinase activity of the cyclin dependent kinase (cdk) enzymes. Therefore p16 gene is known to be an important tumor suppressor gene and is also called MTS1 (multiple tumor suppressor 1). No more oncogenes have been reported to be frequently related to multiple different malignancies than the alterations of p16 gene. Especially when it comes to non-small cell lung cancer, there was no expression of p16 in more than 70% of cell lines examined. And also it is speculated that p16 gene could exert a key role in the development of non-small cell lung cancer. This study was designed to evaluate whether p16 gene could be used as a candidate for gene therapy of non-small cell lung cancer. Methods : After the extraction of total RNA from normal fibroblast cell line and subsequent reverse transcriptase reaction and polymerase chain reaction, the amplified p16 cDNA was subcloned into eukaryotic expression plasmid vector, pRC-CMV. The constructed pRC-CMV-p16 was transfected into the NCI-H441 NSCLC cell line using lipofectin. The changes of G1 cell-cycle related proteins were investigated with Western blot analysis and immunoprecipitation after extraction of proteins from cell lysates and tumor suppressive effect was observed by clonogenic assay. Results : (1) p16(-) NCI-H441 cell line transfected with pRC-CMV-p16 showed the formation of p16 : cdk 4 complex and decreased phosphorylated Rb protein, while control cell line did not. (2) Clonogenic assay demonstrated that the number of colony formation was markedly decreased in p16(-) NCI-H441 cell line transfected with pRC-CMV-p16 than the control cell line. Conclusion : It is confirmed that the expression of p16 protein in p16 absent NSCLC cell line with the gene transfection leads to p16 : cdk4 complex formation, subsequent decrease of phosphorylated pRb protein and ultimately tumor suppressive effects. And also it provides the foundation for the application of p16 gene as a important candidate for the gene therapy of NSCLC.

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2006.10a
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• pp.59-59
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• 2006

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2004.10a
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• pp.81-90
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• 2004

Sialic acid containing glycosphingolipids (gangliosides) have been implicated in the regulation of various biological phenomena such as atherosclerosis. Recent report suggeststhat exogenously supplied disialoganglioside (GD3) serves a dual role in vascular smooth muscle cells (VSMC) proliferation and apoptosis. However, the role of the GD3 synthase gene in VSMC responses has not yet been elucidated. To determine whether a ganglioside is able to modulate VSMC growth. the effect of overexpression of the GD3 synthase gene on DNA synthesis was examined. The results show that the overexpression of this gene has a potent inhibitory effect on DNA synthesis and ERK phosphorylation in cultured VSMC in the presence of PDGF. The suppression of the GD3 synthase gene was correlated with the down-regulation of cyclinE/CDK2. the up-regulation of the CDK inhibitor p21 and blocking of the p27 inhibition,whereas up-regulation of p53 as the result of GD3 synthase gene expression was not observed. Consistently, blockade of GD3 function with anti-GD3 antibody reversed VSMC proliferation and cell cycle proteins. The expression of the CD3 synthase gene also led to the inhibition of TNF--induced matrix metalloproteinase-9 (MMP-9) expression in VSMC as determined by zymography and immunoblot. Furthermore, GD3 synthase gene expression strongly decreased MMP-9 promoteractivlty in response to TNF-. This inhibition was characterized by the down-regulation of MMP-9,which was Iranscriptionally regulated at NF-B and activation protein-1 (AP-1) sites in the MMP-9promoter Finally, the overexpression of MMP-9 in GD3 synthase transfectant cells rescued VSMC proliferation. However MMP-2 overexpression was not affected the cell proliferation. These findings suggest that the fl13 synthase gene represents a physiological modulator of VSMC responses that may contribute to plaque instability in atherosclerosis.