• Tuberculosis and Respiratory Diseases
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• v.45 no.5
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• pp.975-983
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• 1998

Purpose: Frequent deletion of 3p in numerous cancer including lung cancer suggests the presence of tumor suppressor gene. 3p has been analysed by RFLP and PCR-LOH of microsatellite locus. In this study, we observed the deletion of 3p in Korean NSCLC by PCR-LOH of 4 microsatellite loci and investigated the clinical significance. Method: 62 surgically resected NSCLC DNA and normal lung DNA have been analysed by PCR-LOH at three dinucleotide[D3S1228 (3p14.1-14.3), D3S1067 (3p14.3-21.1), D3S1029 (3p21.1-21.3)] and one tetranucleotide[D3S1537 (3p 22-24.2)] repeat microsatellite loci. Results: Among 59 informative cases, 3p deletion by PCR-LOH at four microsatellite loci was found in 31 patients(52.5%). 3p deletion were found in 55% of squamous cell lung cancer and 47% of adenocarcinoma patients. No significant difference has been found in clinical parameters such as staging, smoking and survival according to the status of 3p deletion. Conclusion: Deletions in 3p have played an important role in Korean NSCLC though no clinical significance was detected.

• Journal of Life Science
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• v.21 no.1
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• pp.89-95
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• 2011

p53 is tumor suppressor gene that regulates apoptosis such as caspase-dependent and p21-mediated signaling pathways. PI3K/Akt is known to be over-activated in cancer cells. Akt activates many survival-related signals such as mTOR and COX-2. Inactivation of Akt would result in non-inhibition of p53 as well as induced apoptosis. In this study, we showed that curcumin and EGCG activate p53 via inhibition of the Akt signaling pathway. Treatments using curcumin and EGCG in different concentrations for 24 hr and 48 hr inhibited proliferation of HCT116 colon cancer cells and increased apoptotic cell death. Also, our data showed that curcumin and EGCG increased the p53 expression and decreased the p-Akt. Treatment of LY294002 (Akt inhibitor) resulted in decreased cell proliferation of cancer cells, while LY294002 treated with curcumin or EGCG showed a greater decrease of cell proliferation. In addition, inhibition of Akt induced p53 activation in HCT116 colon cancer cells. These results suggest that curcumin and EGCG induce apoptosis by inhibiting Akt and increase p53 in HCT116 colon cancer cells.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.4
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• pp.973-981
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• 2007

In the present study, we investigated the antiproliferative activity of the water extract of Samgibopae-tang (SGBPT) in NCI-H460 and A549 non-small-cell lung cancer cell lines. We found that exposure of A549 cells to SGBPT resulted in the growth inhibition in a dose-dependent manner as measured by MTT assay, however SGBPT did not affect the growth of NCI-H460 cells. The antiproliferative effect by SGBPT treatment in A549 cells was associated with morphological changes such as membrane shrinking and cell rounding up. SGBPT treatment did not induce the cell cycle arrest in both cell lines, however the frequency of sub-G1 population was concentration-dependently increased by SGBPT treatment in A549 cells. SGBPT treatment partially induced the expression of tumor suppressor p53 in A549 cells and the expression of cyclin-dependent kinase inhibitor p21(WAF1/CIP1) was markedly increased in both transcriptional and translational levels in A549 cells. The up-regulation of p21 by SGBPT occurred in a similar a concentration dependent manner to that observed with the inhibition of cell viability and induction of sub-G1 population of the cell cycle. However SGBPT treatment did not affect other growth regulation-related genes such as early growth response-1 (Egr-1), nonsteroidal anti-inflammatory drug-activated gene-1 (NAG-1), inducible nitric oxide synthease (iNOS), cyclooxygenases (COXs), telomere-regulatory factors in A549 as well as NCI-H460 cells. Taken together, these findings suggested that SGBPT-induced inhibition of human lung carcinoma A549 cell growth was aoosciated with the induction of p21 and the results provided important new insights into the possible molecular mechanisms of the anti-cancer activity of SGBPT.

• International Journal of Stem Cells
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• v.16 no.2
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• pp.215-233
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• 2023

Background and Objectives: MYC, also known as an oncogenic reprogramming factor, is a multifunctional transcription factor that maintains induced pluripotent stem cells (iPSCs). Although MYC is frequently upregulated in various cancers and is correlated with a poor prognosis, MYC is downregulated and correlated with a good prognosis in lung adenocarcinoma. MYC and two other MYC family genes, MYCN and MYCL, have similar structures and could contribute to tumorigenic conversion both in vitro and in vivo. Methods and Results: We systematically investigated whether MYC family genes act as prognostic factors in various human cancers. We first evaluated alterations in the expression of MYC family genes in various cancers using the Oncomine and The Cancer Genome Atlas (TCGA) database and their mutation and copy number alterations using the TCGA database with cBioPortal. Then, we investigated the association between the expression of MYC family genes and the prognosis of cancer patients using various prognosis databases. Multivariate analysis also confirmed that co-expression of MYC/MYCL/MYCN was significantly associated with the prognosis of lung, gastric, liver, and breast cancers. Conclusions: Taken together, our results demonstrate that the MYC family can function not only as an oncogene but also as a tumor suppressor gene in various cancers, which could be used to develop a novel approach to cancer treatment.

• Clinical and Experimental Pediatrics
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• v.51 no.1
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• pp.73-77
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• 2008

Purpose : p16 gene, mapped to the 9p21 chromosomal region, has emerged as a candidate tumor suppressor gene in human neoplasm. It is an inhibitor of cyclin-dependent kinase and inhibits Rb phosphorylation. In a variety of tumors including childhood acute lymphoblastic leukemia (ALL), deletion and/or mutation of the p16 gene has been found. Despite their high frequency, the prognostic importance of p16 alterations is still controversial in ALL and has been reported to be either unfavorable or similar to that of other patients. We studied the correlation between loss of p16 protein confirmed by immunohistochemical staining and clinical outcomes of patients diagnosed as ALL. Methods : We performed an immunohistochemical staining for p16 protein in 74 cases of bone marrow biopsy slide initially diagnosed as ALL between January 1998 and December 2006. We reviewed the clinical manifestations, laboratory findings, treatment outcomes retrospectively. Results : Of 74 slides, 12 were negative for p16 protein. Seven were males and 5 were females with a median age at diagnosis was 5.8 (1.3-18.8) years. Initial WBC were 17,225 $(500-403,300)/{\mu}L$. By immunologic surface marker analysis, 7 patients were early pre-B CALLA (+) and 5 patients were T-cell ALL. Two patients of intermediate risk group had relapsed and died. Three patients had family history of breast cancer. Four patients died and overall survival rates were $53.5{\pm}18.7%$. Conclusion : Loss of p16 protein is supposed to be an independent risk factor of childhood ALL associated with poor outcomes. In clinical setting, the clinician must take into account p16 status, not only at the genomic but also at the protein level. Further clinical experience on thoroughly investigated cases will help a better understanding between p16 status and clinical outcomes.

• Journal of Life Science
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• v.28 no.6
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• pp.718-725
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• 2018

Toll-like receptor 4 (TLR4) has been implicated in cell proliferation and apoptosis in several types of cancer. In this study, the impact of TLR4 activation on apoptotic cell death in gynecologic cancers induced by lipopolysaccharide (LPS) was investigated. Cervical cancer cell lines were produced from isolated surgical specimens supplied by Paik Hospital. The primary cultures of normal myometrium and gynecologic cancers, including cervical, endometrial, and ovarian cancers, were used to examine the differences in morphological characteristics between normal and cancerous cells. A reverse transcription polymerase chain reaction analysis was used to determine the relative expression levels of TLR4 gene involved in apoptosis-associated signaling in cervical cancer cells. The cancer cell colonies showed a tendency to reach high levels of confluency compared with normal cells. In addition, an enhanced growth rate and loss of contact inhibition were observed in gynecologic cancer cells compared with normal cells (doubling times of 16.6 hr vs. 26 hr, respectively). The expression level of ITGA5, an alpha-5 integrin marker, was upregulated in normal myometrial cells, but this tendency was not exhibited in cervical cancer cells. Furthermore, p53 tumor suppressor gene expression was upregulated, whereas TLR4 and caspase-3 gene expressions were downregulated in cervical cancer cells. Notably, the expression levels of TLR4 and caspase-3 were increased significantly in LPS-treated cancer cells compared with those in non-LPS-treated cells. These results suggest that the TLR4-mediated caspase-dependent apoptotic signaling pathway could be suggested as a therapeutic target for the treatment of gynecologic cancers, including cervical cancers.

• Korean Journal of Microbiology
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• v.43 no.3
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• pp.151-158
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• 2007

The possibility of inadvertent introduction of therapeutic gene expressing viral vectors has raised safety concerns about germ-line infection. Particularly, for indications such as prostate cancer and ovarian cancer, the proximity of the point of viral administration to organs of the reproductive system raises concerns regarding inadvertent germ-line transmission of genes carried by the virus vector. To evaluate the safety of in vivo adenovirus mediated gene transfer, we explored the biodistribution, persistance and potential germ-line transmission of p53-expressing adenovirus (Ad-CMV-p53). Both male and female Balb/c mice were injected with $1{\times}10^9$ PFU of Ad-CMV-p53. The PCR analysis showed that there were detectable vector sequences in liver, kidney, spleen, seminal vesicle, epididymis, prostate, ovary, and uterus. The RT-PCR analysis for detecting inserted gene, p53 showed that Ad-CMV-p53 viral RNA were present in spleen, prostate and ovary. Direct injected male and female mice of adenovirus vector into testis and ovary were mated and their of offspring were evaluated for germ-line transmission of the adenoviral vector. The PCR and RT-PCR analysis showed no evidence of germline transmission, although vector sequences were detected in DNA extracted from gonadal tissues. Real-time PCR result confirmed a significant decrease of adenovirus in gonad tissues 1 week after injection. We have also analysed the cell specific localization of viral DNA in gonad tissues by using in-situ PCR. Positive signals were detected in interstitial tissue but not in seminiferous tubule in sperm. In the case of ovary, adenovirus signal were localized to the stromal tissue, but no follicular signals were observed. Together, these data provide strong evidence that the risk of the Inadvertent germ-line transmission of vector sequences following intraperitoneal or direct injection into genito-urinary system of adenovirus is extremely low.

• Tuberculosis and Respiratory Diseases
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• v.50 no.6
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• pp.668-675
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• 2001

Background : Non-smalll lung cancer(NSCLC) develops as a result of the accumulation of multiple genetic abnormalities. Loss of heterozygosity(LOH) is one of the most frequent genetic alterations that is found in NSCLC, and the chromosomal regions that display a high rate of LOH are thought to harbor tumor suppressor genes(TSGs). This study was done to determine the frequency of LOH in 21q with the aim of identifying potential TSG loci. Method : Thirty-nine surgically resected NSCLCs were analysed. Patients peripheral lymphocytes were used as the source of the normal DNA. Five microsatellite Inarkers of 21q were used to study LOH : 21q21.1(D21S1432, and D21S1994); 21q21.2-21.3(D21S1442) ; 21q22.1(21S1445) ; and 21q22.2-22.3(D21S266). The fractional allelic loss(FAL) in a tumor was calculated as the ratio of the number of markers showing LOH to the number of informative markers. Result : LOH for at least one locus was detected in 21 of 39 tumors(53.8%). Among the 21 tumors with LOH, 5(21.8%) showed LOH at almost all informative loci. Although statistically not significant, LOH was found more frequently in squamous cell carcinomas(15 of 23, 65.2%) than in adenocarcinomas(6 of 16, 37.5%). In the squamous cell carcinomas the frequency of LOH was higher in stage II-III (80.0%) than in stage I (53.8%). The FAL value in squamous cell carcinomas($0.431{\pm}0.375$) was significantly higher than that found in adenocarcinomas($0.l92{\pm}0.276$). Conclusion : These results suggest that LOH on 21q may be involved in the development of NSCLC, and that TSG(s) that contribute to the pathogenesis of NSCLC may exist on 21q.

• Journal of Life Science
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• v.27 no.2
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• pp.149-154
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• 2017

Diffuse large B-cell lymphoma (DLBCL) is the most common type of non-hodgkin lymphoma. Advances in the chemotherapeutic treatment of this disease have improved the outcomes of DLBCL; nonetheless, many patients still die of DLBCL, and therefore, a better understanding of this disease and identification of novel therapeutic targets are urgently required. In a recent gene expression profiling study, PDE (phosphodiesterase) 4B was found to be overexpressed in chemotherapy-resistant tumors. The major function of PDE4B is to inactivate the second messenger cyclic 3',5' monophosphate (cAMP) by catalyzing the hydrolysis of cAMP to 5'AMP. It is known that cAMP induces cell cycle arrest and/or apoptosis in B cells, and PDE4B abolishes cAMP's effect on B cells. However, the mechanism by which PDE4B is overexpressed remains unclear. Here, we show that the aberrant expression of miRNA may be associated with the overexpression of this gene. The PDE4B 3' untranslated region (UTR) has three functional binding sites of miR-23b, as confirmed by luciferase reporter assays. Interestingly, miR-23b-binding sites were evolutionarily conserved from humans to lizards, implying the critical role of PDE4B-miR-23b interaction in cellular physiology. The ectopic expression of miR-2 3b repressed PDE4B mRNA levels and enhanced intracellular cAMP concentrations. Additionally, miR-23b expression inhibited cell proliferation and survival of DLBCL cells only in the presence of forskolin, an activator of adenylyl cyclase, suggesting that miR-23b's effect is via the downregulation of PDE4B. These results together suggest that miR-23b could be a therapeutic target for overcoming drug resistance by repressing PDE4B in DLBCL.

• Journal of Life Science
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• v.28 no.5
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• pp.615-620
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• 2018

Epigallocatechin-3-gallate (EGCG), one of catechins of green tea, has been known to possess anti-oxidation, anti-inflammation, and anti-cancer effects. The present study analyzed global gene expression changes in EGCG-treated HCT116 cells and p53-null HCT116 cells by oligo DNA microarray analysis. Among the differentially expressed genes in EGCG-treated HCT116 cells, four were selected that are known as tumor suppressor genes (activating transcription factor 3 [ATF3], cyclin dependent kinase inhibitor 1A [CDKN1A], DNA damage-inducible transcript 3 [DDIT3] and non-steroidal anti-inflammatory drug activated gene [NAG-1]) and their expression was compared to the expression of genes in p53-null HCT116 cells. We found that the expression of these genes was not dependent on their p53 status except for NAG-1, which was only up-regulated in HCT116. The results of RT-PCR and Western blot analysis showed that ATF3 up-regulation by EGCG was not affected by the presence of p53, whereas NAG-1 expression was not induced in p53-null HCT116 cells. We also detected ATF3 and NAG-1 expression changes through genistein and resveratrol treatment. Interestingly, genistein could not up-regulate ATF3 regardless of p53 status, but genistein could induce NAG-1 only in HCT116 cells. Resveratrol could significantly induce NAG-1 as well as ATF3 independent of p53 presence. These results indicate that EGCG, genistein and resveratrol may have different anti-cancer effects. Overall, the results of this study may help to increase our understandings of molecular mechanisms on anti-cancer activities mediated by EGCG, genistein and resveratrol in human colorectal cancer cells.