• Journal of Microbiology and Biotechnology
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• v.34 no.4
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• pp.774-782
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• 2024

This study aimed to elucidate the anti-colon cancer mechanism of ginsenoside Rg1 in vitro and in vivo. Cell viability rate was detected using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) tetrazolium assay. The inhibitory effect of ginsenoside Rg1 against CT26 cell proliferation gradually increased with increasing concentration. The in vivo experiments also demonstrated an antitumor effect. The monodansylcadaverine (MDC), transmission electron microscopy (TEM), and expression of autophagy marker proteins confirmed that ginsenoside Rg1 induced autophagy in vitro. Ginsenoside Rg1 induced autophagy death of CT26 cells, but this effect could be diminished by autophagy inhibitor (3-methyladenine, 3-MA). Additionally, in a xenograft model, immunohistochemical analysis of tumor tissues showed that the LC3 and Beclin-1 proteins were highly expressed in the tumors from the ginsenoside Rg1-treated nude mice, confirming that ginsenoside Rg1 also induced autophagy in vivo. Furthermoer, both in vivo and in vitro, the protein expressions of p-Akt, p-mTOR, and p-p70S6K were inhibited by ginsenoside Rg1, which was verified by Akt inhibitors. These results indicated that the mechanism of ginsenoside Rg1 against colon cancer was associated with autophagy through inhibition of the Akt/mTOR/p70S6K signaling pathway.

• Tuberculosis and Respiratory Diseases
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• v.50 no.6
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• pp.676-685
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• 2001

Background : Angiogenesis is an essential component of tumor growth and metastasis, and the vascular endothelial growth factor (VEGF) is one of the most important angiogenic factors. Several solid tumors produce substantial amounts of VEGF, which stimulates proliferation and the migration of endothelial cells, thereby inducing neovasculization by a paracrine mechanism. To evaluate the prognostic roles of angiogenesis and VEGF expression in patients with non-small cell lung cancer, the relationship between VEGF expression in tumor tissues, the clinicopathologic features and the overall survival rate were analysed. Methods : Sixty-nine resected primary non-small cell lung cancer specimens were evaluated. The paraffin-embedded tumor tissues were stained by anti-VEGF polyclonal antibodies using an immunohistochemical method to assess VEGF expression. Results : In Forty-one patients (59%), the VEGF antigen was expressed weakly in their tumor tissue, whereas in twenty-eight patients (41%) the VEGF antigen was expressed strongly. The median survival time of the weak VEGF expression group was 24 months, and that of the strong VEGF expression group was 19 months. The three year-survival rates were 35%, 33%, respectively. The survival difference between both groups was not statistically significant. Conclusion : Although results were not statistically significant, the strong expression group tended to poorer prognosis than the weak expression group.

• Journal of Chest Surgery
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• v.39 no.11 s.268
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• pp.828-837
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• 2006

Background: Tissue hypoxia is characteristic of many human malignant neoplasm, and hypoxia inducible factor-1(HIF-1) plays a pivotal role in essential adaptive response to hypoxia, and activates a signal pathway for the expression of the hypoxia-regulated genes, resulting in increasing $O_2$ delivery or facilitating metabolic adaptation to hypoxia. Increased level of HIF-$1{\alpha}$ has been reported in many human malignancies, but in non-small cell lung carcinoma the influence of HIF-$1{\alpha}$ on tumor biology, including neovascularization, is not still defined. In present study the relationship of HIF-$1{\alpha}$ expression on angiogenetic factors, relationship between the tumor proliferation and HIF-$1{\alpha}$ expression, interaction of HIF-$1{\alpha}$ expression and p53, and relationship between HIF-$1{\alpha}$ expression and clinico-pathological prognostic parameters were investigated. Material and Method: Archival tissue blocks recruited in this study were retrieved from fifty-nine patients with primary non-small cell lung carcinoma, who underwent pneumonectomy or lobectomy from 1997 to 1999. HIF-$1{\alpha}$, VEGF(vascular endothelial growth factor), and p53 protein expression and Ki-67 labeling index in tumor tissues were evaluated, using a standard avidin-biotin-peroxidase complex(ABC) immunohistochemistry. Relationship between the HIF-$1{\alpha}$ expression and VEGF, p53 overexpression and correlation between the HIF-$1{\alpha}$ expresseion and Ki-67 index were analyzed. Clinico-pathologic prognostic parameters were also analyzed. Result: HIF-$1{\alpha}$ expression in cancer cells was found in 24 of 59 cases of non-small cell lung carcinoma(40.7%). High HIF-$1{\alpha}$ expression was significantly associated with several pathological parameters, such as pathological TMN stage(p=0.004), pT stage(p=0.020), pN stage (p=0.029), and lymphovascular invasion(p=0.019). High HIF-$1{\alpha}$ expression was also significantly associated with VEGF immunoreactivity(p<0.001), and aberrant p53 expression(p=0.040). but was marginally associated with Ki-67 labeling index(p=0.092). The overall 5-year survival rate was 42.3%. The survival curve of patients with a high HIF-$1{\alpha}$ expression was worse than that of patients with low-expression(p=0.002). High HIF-$1{\alpha}$ expression was independent unfavorable factors with a marginal significance in multivariate analysis performed by Cox regression. Conclusion: It is suggested that high HIF-$1{\alpha}$ expression may be associated with intratumoral neovascularization possibly through HIF-VEGF pathway, and high HIF-$1{\alpha}$ expression could be associated with lymph node metastasis and post operative poor prognosis in patients with non-small cell lung carcinoma.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.27 no.5
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• pp.373-384
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• 2001

Cellular proliferation is an intricately regulated process mediated by the coordinated interactions of critical growth control genes. Two of these factors in mammalian cells are the p53 and mdm-2 genes. A protein product of the mem-2 oncogene has been recently shown to associate with the protein encoded by the tumor suppressor gene p53. The p53 tumor suppressor protein is stabilized in response to DNA damage and other stress signals and causes the cell to undergo growth arrest or apoptosis, thus preventing the establishment of mutations in future cellular generations. Mutation or loss of p53 is a very common event in tumor progression. It occurs in about 50% of all tumors analysed including of colon, lung, breast and liver. The cellular mdm-2 gene, which has potential transforming activity that can be activated by overexpression, is amplified in a significant percentage of human sarcoma and in other mammalian tumors. Proteins encoded by the mdm-2 gene are able to bind to the p53 protein and, when overexpressed, can inhibit p53's transcriptional activation function, thus mdm-2 can act as a negative regulator of p53 function. Experimental study was performed to observe the relationship between p53 gene mutation and mdm-2 protein expression and apply the results to the clinical activity. 36 golden syrian hamster each weighing $60{\sim}80g$ were used and painted with 0.5% DMBA by 3 times weekly on the right buccal cheek(experimental side) for 6, 8, 10, 12, 14 and 16 weeks. Left buccal cheek(control side) was treated with mineral oil as the same manner to the right side. The hamsters were sacrificed on the 6, 8, 10, 12, 14 & 16 weeks. Normal and tumor tissues from paraffin block were examined for histology and immunohistochemistry observation, and were completely dissected by microdissection and DNA from both tissue were isolated by proteins K/phenol/chloroform extraction. Segments of the hamster p53 exons 5, 6, 7 and 8 were amplified by PCR using the oligonucleotide primers, and then confirmational change was observed by SSCP respectively. The results were as follows : 1. Dysplasia at 6 weeks, carcinoma in situ at 8 weeks and invasive carcinoma from 10 weeks could be observed in experimental groups. 2. p53 mutations were detected in 10 of the 36(28%) and the exons 6(6 of the 10 : 60%) was the most hot spot area among the highy conserved region(exons 5, 6, 7 & 8). 3. Immunohistochemical study confirmed 22 of the 36(61%) of p53 expression involving 10 of p53 mutations. 4. mdm-2 expression of was showed in 3 of the 36(8%) involving 1 of the 22 of p53 expression and 2 of the 14 of p53 non-expression. From the above results, mutation of p53 gene or expression of p53 protein may have the influence of the DMBA induced carcinoma of hamster buccal pouch but the expression of mdm-2 protein may not have relationship with tumorigenesis.

• Tuberculosis and Respiratory Diseases
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• v.63 no.3
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• pp.242-250
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• 2007

Background: Abnormal angiogenesis can induce hypoxia within a highly proliferating tumor mass, and these hypoxic conditions can in turn create clinical problems, such as resistance to chemotherapy. However, the mechanism by which hypoxia induces these changes has not yet been determined. Therefore, this study was conducted to determine how hypoxia induces changes in cell viability and extracellular microenvironments in an in vitro culture system using non-small cell lung cancer cells. Methods: The non-small cell lung cancer cell line, A549 was cultured in DMEM or RPMI-1640 media that contained fetal bovine serum. A decrease in the oxygen tension of the media that contained the culture was then induced in a hypoxia microchamber using a $CO_2-N_2$ gas mixture. A gas analysis and an MTT assay were then conducted. Results: (1) The decrease in oxygen tension was checked the anaerobic gas mixture for 30 min and then reoxygenation was induced by adding a 5% $CO_2-room$ air gas mixture to the chamber. (2) Purging with the anaerobic gas mixture was found to decrease the further oxygen tension of cell culture media. (3) The low oxygen tension resulted in a low pH, lactic acidosis and a decreased glucose concentration in the media. (4) The decrease in glucose concentration that was observed as a result of hypoxia was markedly different when different types of media were evaluated. (5) The decrease in oxygen tension inhibited proliferation of A549 cells. Conclusion: These data suggests that tumor hypoxia is associated with acidosis and hypoglycemia, which have been implicated in the development of resistance to chemotherapy and radiotherapy.

• Radiation Oncology Journal
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• v.20 no.1
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• pp.73-80
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• 2002

Purpose : Tumor growth in a given neoplasm is the net result of cell proliferation and cell loss, and apoptosis is the most significant component of continuous cell loss in most tumors. In this study, we examined non-Hodgkin's lymphoma (NHL, n=67) immunohistochemically for the presence of Bcl-2 oncoprotein and P53 protein and compared apoptotic indices (Als) and Ki-67 proliferative indices (percentages of Ki-67 positive cells). Materials and Methods : 67 patients with NHL were evaluated : 3 low-grade and 64 intermediate-grade. The phenotype was determined in 65 cases : 47 $(70\%)$ were B cell type and 18 $(27\%)$ were T ceil type. Als and Ki-67 proliferative indices were determined immunohistochemically and the overexpression of P53 and Bcl-2 protein were also evalutated. Results : The overexpressions of Bcl-2 protein and P53 protein were found in $40\%$ (26/65) and $31\%$ (20/65). The Al ranged from $0\%\;to\;15\%$ (mean 2.16, median 1.2). Cellular Bcl-2, which counteracts apoptosis, was significantly (p=0.005) associated with Als. Ki-67 proliferative indices ranged from $1\%\;to\;91\%$ (mean 55.4), and P53 was significantly (p=0.000) associated with Ki-67 proliferative indices. A positive correlation between Als and Ki-67 proliferative indices was revealed (p=0.012) in Bcl-2 positive patients. Conclusion : In NHL, we observed a correlation between Als and Bcl-2 expression, between Ki-67 proliferative indices and P53 expression, and between Als and Ki-67 proliferative indices in Bcl-2 positive patients. Our results suggest that cell apoptosis may be inseparable from cell proliferation during tumor growth.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.6
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• pp.767-774
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• 2011

Defatted green tea seed was extracted with 100% ethanol for 4 hr and then fractionated with petroleum ether, ethyl acetate and butanol. The ethanol and butanol extracts showed greater increases in antiproliferation potential against liver cancer cells than petroleum ether, ethyl acetate, $H_2O$, and hot water extracts did. Thus, this study was carried out to investigate the anti-proliferative actions of defatted green tea seed ethanol extract (DGTSE) in HepG2 cancer cells. The DGTSE contained catechins including EGC ($1039.1{\pm}15.2\;g/g$), tannic acid ($683.5{\pm}17.61\;{\mu}g/g$), EC ($62.4{\pm}5.00\;{\mu}g/g$), ECG ($24.4{\pm}7.81\;{\mu}g/g$), EGCG ($20.9{\pm}0.96\;{\mu}g/g$) and gallic acid ($2.4{\pm}0.68\;{\mu}g/g$), but caffeic acid was not detected when analyzed by HPLC. The anti-proliferation effect of DGTSE toward HepG2 cells was 83.13% when treated at $10\;{\mu}g$/mL, of DGTSE, offering an $IC_{50}$ of $6.58\;{\mu}g$/mL. DGTSE decreased CYP1A1 and CYP1A2 protein expressions in a dose-dependent manner. Quinone reductase and antioxidant response element (ARE)-luciferase activities were increased about 2.6 and 1.94-fold at a concentration of $20\;{\mu}g$/mL compared to a control group, respectively. Enhancement of phase II enzyme activity by DGTSE was shown to be mediated via interaction with ARE sequences in genes encoding the phase enzymes. DGTSE significantly (p<0.05) suppressed prostaglandin $E_2$ level, tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) protein expressions, and NF${\kappa}$B translocation, but did not affected nitric oxide production. From the above results, it is concluded that DGTSE may ameliorate tumor and inflammatory reactions through the elevation of phase II enzyme activities and suppression of NF${\kappa}$B translocation and TNF-${\alpha}$ protein expressions, which support the cancer cell anti-proliferative effects of DGTSE in HepG2 cells.

• Korean Journal of Microbiology
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• v.42 no.4
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• pp.319-325
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• 2006

[ $\beta$ ]-Glucans (AG) were prepared from Agaricus blazei cultured in the medium fortified with the roots of Pueraria spp. by repeated extraction with hot water, gel filtration chromatography and DEAE ion exchange chromatography. Oligosaccharides (AO) were derived from the hydrolysis of AG by an endo-$\beta$-(1$\rightarrow$6)-glucanase from Bacillus megaterium. The anti-HT-29 human colon cancer activity of AG or AO was investigated using MTT assay, apoptosis assay, cell cycle analysis, and cDNA microairay. AG and AO both inhibited proliferation and growth of HT-29 cells, and stimulated apoptosis of the cells in a dose-dependent manner. In cell cycle analysis, treating HT-29 cells with AG or AO resulted in the increase of cells in the G0 (sub-G1) and G1 phase. Especially, AO was more effective in inducing G0/G1 cell cycle arrest than AG. To screen the genes involved in the increase of apoptosis, the gene expression profile of the HT-29 cells treated with AO was examined by cDNA microarray. While several genes involved in cell cycle progression (CCND2 and CDK2) were down-regulated, many genes involved in apoptosis (TNFSF9, TNFRSF9, FADD, CASP8, BAD, CRADD, CASP9 etc), cell cycle inhibitor (CDKN2A), immune response (IL6, IL18, IL6R etc), and tumor suppressor (CEACAM1, TP53BP2, IRF1, and PHB) were up-regulated. These results suggest that AO could inhibit the proliferation and growth of HT-29 cells by G0/G1 cell cycle arrest and induction of apoptosis.

• Tuberculosis and Respiratory Diseases
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• v.46 no.1
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• pp.36-43
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• 1999

Background : Tumor growth is the net result of intrinsic proliferation and escape from active cell death. bcl-2 is a member of a new category of oncogenes that is not involved in influencing cell proliferation but is involved in regulating cell death(apoptosis). Based on this information, it seems to be reasonable to expect that there may be clinical prognostic significance of bcl-2 expression in non-small cell lung cancer. But its prognostic significance is not established. Methods: To investigate the role of bcl-2 in lung cancer, we performed immunohistochemical stain of bcl-2 on 57 biopsy specimens from resected primary non-small cell lung cancer. Thereafter, flow cytometric cell cycle analysis was done. And we analyzed the correlation between bcl-2 expression, clinical parameters, S-, $G_1$-phase fraction and survival. Results: bcl-2 were detected in 43.8% of total 57 patients(according to histology, squamous cancer 47%, adenocarcinoma 32%, according to TNM stage, I 28.6%, II 52.3%, III 45.5%. both differences were insignificant). By using the flow cytometric analysis, mean S-phase fraction of bcl-2(+) and (-) group were 14.1($\pm7.8$)%, 24.7($\pm10.5$)% (p<0.005), mean $G_1$-phase fraction of bcl-2(+) and bcl-2(-) group were 75.5($\pm10.8$)%, 65.5($\pm11.4$)%(p<0.05). 2yr, 3yr and 5yr survival and median survival time of bcl-2(+) group were 65%, 54%, 41%, 53 months, and those of bcl-2(-) group were 71%, 52%, 46%, 37 months. (p>0.05, Kaplan-Meier, log rank) Conclusion: bcl-2 was detected in 43.8% of primary non-small cell lung cancer. The S-phase fraction of bcl-2(+) group was less than bcl-2(-) group, and G1-phase fraction of bcl-2(+) group was more than bcl-2(-) group. But, expression of bcl-2 could not be a prognostic factor.

• Radiation Oncology Journal
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• v.21 no.1
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• pp.54-65
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• 2003

Purpose : To analyze the gene expression Profiles of uterine ceulcal cancer, and its variation after radiation therapy, with or without concurrent chemotherapy, using a CDNA microarray. Materials and Methods :Sixteen patients, 8 with squamous ceil carcinomas of the uterine cervix, who were treated with radiation alone, and the other 8 treated w14h concurrent chemo-radiation, were Included in the study. Before the starling of the treatment, tumor biopsies were carried out, and the second time biopsies were peformed after a radiation dose of 16.2$\~$27 Gy. Three normal cervix tissues were used as a control group. The microarray experiments were peformed with 5 groups of the total RNAs extracted individually and then admixed as control, pre-radiation therapy alone, during-radiation therapy alone, pre-chemoradiation therapy, and during-chemoradlation therapy. The 33P-iabeled CDNAS were synthesized from the total RNAs of each group, by reverse transcription, and then they were hybridized to the CDNA microarray membrane. The gene expression of each microarrays was captured by the intensity of each spot produced by the radioactive isotopes. The pixels per spot were counted with an Arrayguage, and were exported to Microsoft Excel The data were normalized by the Z transformation, and the comparisons were peformed on the Z-ratio values calculated. Results : The expressions of 15 genes, including integrin linked kinase (ILK), CDC28 protein kinase 2, Spry 2, and ERK 3, were increased with the Z-ratio values of over 2.0 for the cervix cancer tissues compared to those for the normal controls. Those genes were involved In cell growth and proliferation, cell cycle control, or signal transduction. The expressions of the other 6 genes, Including G protein coupled receptor kinase 5, were decreased with the Z-ratio values of below -2.0. After the radiation thorapy, most of the genes, with a previously Increase expressions, represented the decreased expression profiles, and the genes, with the Z-ratio values of over 2.0, were cyclic nucleotlde gated channel and 3 Expressed sequence tags (EST). In the concurrent chemo-radiation group, the genes involved in cell growth and proliferation, cell cycle control, and signal transduction were shown to have increased expressions compared to the radiation therapy alone group. The expressions of genes involved in anglogenesis (angiopoietln-2), immune reactions (formyl peptide receptor-iike 1), and DNA repair (CAMP phosphodiesterase) were increased, however, the expression of gene involved In apoptosls (death associated protein kinase) was decreased. Conclusion : The different kinds of genes involved in the development and progression of cervical cancer were identified with the CDNA microarray, and the proposed theory is that the proliferation signal stalls with ILK, and is amplified with Spry 2 and MAPK signaling, and the cellular mitoses are Increased with the increased expression oi Cdc 2 and cell division kinases. After the radiation therapy, the expression profiles demonstrated 4he evidence of the decreased cancer cell proliferation. There was no sigificant difference in the morphological findings of cell death between the radiation therapy aione and the chemo-radiation groups In the second time biopsy specimen, however, the gene expression profiles were markedly different, and the mechanism at the molecular level needs further study.