Growth-inhibitory effect of adenovirus-mediated p53 gene transfer on medulloblastoma cell line, Daoy, harboring mutant p53

To improve the survival rate, gene therapy, such as the replacement of inactivated tumor suppressor genes, has become a new investigational adjuvant treatment modality for human malignancies. We investigated the effect of adenovirus(Ad)-mediated transfer of wildtype p53 tumor suppressor gene on the medulloblastoma cell line, Daoy, which harbors mutant-type p53 gene. At 50 multiplicity of infection (moi), immunohistochemical staining with p53 monoclonal antibody showed positive staining in all cells 2 days after Ad-CMV-p53 infection. The high expression of wild-type p53 protein was detected in Ad-CMV-p53-infected cells, and expression of wild-type p53 protein peaked on day 2 after the infection. The growth of Ad-CMV-p53-infected cells was greatly suppressed in vitro, and the Ad-CMV-p53 treatment significantly reduced the tumor mass in vivo. The mean weight of Ad-CMV- infected tumors was only 16% of those which were mock infected, and 25% of those which were Ad-CMV-beta-gal infected. On microscopic examination, Ad-CMV-p53-infected tumors showed numerous apoptotic bodies. This Ad-CMV-p53 gene transfer showed high transduction efficacy and expression, resulting in significant growth inhibition of Daoy harboring mutant type p53.

Growth inhibitory effect on glioma cells of adenovirus-mediated p16/INK4a gene transfer in vitro and in vivo

The tumour suppressor gene p16/INK4a encodes a specific inhibitor of the cyclin D-dependent kinases CDK4 and CDK6. p16/INK4a prevents the association of CDK4 with cyclin D1, and subsequently inhibits phosphorylation of retinoblastoma tumour suppressor protein (pRb), thus preventing exit from the G1 phase. In human cancers, the estimated frequency of genetic alteration involving the p16/INK4a locus is believed to be second only to alteration of p53. A high frequency (greater than 50%) of homozygous p16/INK4a gene deletion has been demonstrated in glioblastoma tissues and p16/INK4a is altered in 80% of glioma cell lines. Therefore, restoration of p16/INK4a would suppress cell proliferation and induce cell growth arrest. We showed here that restoration of p16/INK4a expression in p16 negative U87MG, U251MG and partially deleted U373MG by Ad-CMV-p16/INK4a induced growth suppression in vitro and in vivo. Expression of p16 transferred by Ad-CMV-p16/INK4a in glioma cells was highly efficient and maintained for more than seven days. In addition, we found that the endogenous status of p16 and Rb might affect the expression of exogenous p16/INK4a gene and inhibitory effect of cell proliferation. Even though, there were several factors affecting the efficiency of Ad-CMV-p16/INK4 gene transfer, our results suggest that Ad-CMV-p16 gene therapy strategy is potentially useful and warrants further clinical investigation for the treatment of gliomas.

A new caffeoyl quinic acid from aster scaber and its inhibitory activity against human immunodeficiency virus-1 (HIV-1) integrase

The phytochemical study of the aerial parts of Aster scaber Thunb. (Asteraceae) yielded a new caffeoyl quinic acid, (-) 3,5-dicaffeoyl-muco-quinic acid (2) and three known compounds, (-) 3,5-dicaffeoyl quinic acid (1), (-) 4,5-dicaffeoyl quinic acid (3), (-) 5-caffeoyl quinic acid (4). The structures were established by high resolution spectroscopic methods. The antiviral effects against HIV-1 integrase of the compounds was evaluated. (-) 3,5-Dicaffeoyl-muco-quinic acid (2) exhibited potent antiviral activity with an IC50 value of 7.0 +/- 1.3 microg/ml.

Growth inhibitory effect on glioma cells of adenovirus-mediated p16/INK4a gene transfer in vitro and in vivo

The tumour suppressor gene p16/INK4a encodes a specific inhibitor of the cyclin D-dependent kinases CDK4 and CDK6. p16/INK4a prevents the association of CDK4 with cyclin D1, and subsequently inhibits phosphorylation of retinoblastoma tumour suppressor protein (pRb), thus preventing exit from the G1 phase. In human cancers, the estimated frequency of genetic alteration involving the p16/INK4a locus is believed to be second only to alteration of p53. A high frequency (greater than 50%) of homozygous p16/INK4a gene deletion has been demonstrated in glioblastoma tissues and p16/INK4a is altered in 80% of glioma cell lines. Therefore, restoration of p16/INK4a would suppress cell proliferation and induce cell growth arrest. We showed here that restoration of p16/INK4a expression in p16 negative U87MG, U251MG and partially deleted U373MG by Ad-CMV-p16/INK4a induced growth suppression in vitro and in vivo. Expression of p16 transferred by Ad-CMV-p16/INK4a in glioma cells was highly efficient and maintained for more than seven days. In addition, we found that the endogenous status of p16 and Rb might affect the expression of exogenous p16/INK4a gene and inhibitory effect of cell proliferation. Even though, there were several factors affecting the efficiency of Ad-CMV-p16/INK4 gene transfer, our results suggest that Ad-CMV-p16 gene therapy strategy is potentially useful and warrants further clinical investigation for the treatment of gliomas.

Effect of pentoxifylline on radiation response of non-small cell lung cancer: a phase III randomized multicenter trial

PURPOSES

The objectives of this prospective clinical trial were to determine whether pentoxifylline improves the radiation response and survival in patients with non-small cell lung cancer.

MATERIALS AND METHODS

From July 1993 through October 1994, 64 patients with histologically confirmed Stage I, II and III non-small cell lung cancer were randomly divided into pentoxifylline (Pento)+Radiotherapy (RT) group and RT alone group. Out of the 64 patients, only 47 patients who had measurable tumors on chest X-ray views were analyzed and divided into Pento+RT group (n=27) and RT alone group (n=20). Total tumor dose of 65-70 Gy was delivered as conventional fractionated radiation schedules. Pento was given to the patients 3 x 400 mg/day with a daily dose of 1200 mg during RT.

RESULTS

Complete response (CR), partial response (PR), and stable in Pento+RT group were three (11%), 13 (48%), and 11 (41%), respectively, as compared with corresponding values of three (15%), 13 (65%), and four (20%) in the RT alone group. The median time to relapse in the Pento+RT group was 11 months which was 2 months longer than for the RT alone group (P>0.05). All the patients in both groups showed lower than or equal to grade 2 dysphagia, odynophagia, pulmonary fibrosis, and pneumonitis. The median survival was 18 months in the Pento+RT group and 7 months in the RT alone group. The 1-year survival rate was 60% in the Pento+RT group and 35% in the RT alone group, the 2-year survival rate was 18% in the Pento+RT group and 12% in the RT alone group. But these differences were not statistically significant (P>0.05).

CONCLUSION

We concluded that Pento is a modestly effective radiation response modifier and provide benefit in the treatment of non-small cell lung cancer.

New cytotoxic butanolides from Lindera obtusiloba BLUME

Three new butanolides, 2-(1-methoxy-11-dodecenyl)-penta-2,4-dien-4-olide (1), (2Z,3S,4S)-2-(11-dodecenylidene)-3-hydroxy-4-methylbutano lide (2) and (2E,3R,4R)-2-(11-dodecenylidene)-3-hydroxy-4-methoxy-4-methylbu tanolide (3), were isolated from the stems of Lindera obtusiloba BLUME. Their chemical structures were assigned by spectroscopic evidence. They exhibited cytotoxicity against cultured human tumor cell lines with their ED50 values ranging from 3.19 to 14.63 microg/ml.

Cytotoxic peroxides from Artemisia stolonifera

Two sesquiterpene endoperoxides, 1S, 4R, 6R-1, 4-endoperoxy-bisabola-2, 10-diene (I), 1R, 4S, 6R-1, 4-endoperoxy-bisabola-2, 10-diene (II), and a sesquiterpene hydroperoxide, 1beta-hydroperoxygermacra-4 (15), 5, 10 (14)-triene (III) were isolated from the aerial parts of Artemisia stolonifera (Compositae). Their chemical structures were assigned by spectral evidences. Compounds I and II exhibited cytotoxicity against five human tumor cell lines with their ED50 values ranging from 0.20 to 5.43 microg/ml and from <0.1 to 0.87 microg/ml, respectively.

High cyclooxygenase-2 expression in stage IB cervical cancer with lymph node metastasis or parametrial invasion

OBJECTIVE

The enzymes cyclooxygenase (COX)-1 and -2 are necessary for the synthesis of prostaglandins. COX-2 is usually absent in normal cells and is upregulated and expressed as a product of the "immediate early" gene during inflammatory processes. In previous studies, the expression of COX-2 has been shown to be induced by proinflammatory cytokines, and suggestions have been made that overexpression of COX-2 suppresses apoptosis and is directly related to tumor growth. We have attempted to determine a relationship between tumor invasion and metastasis of uterine cervical cancer and COX and apoptosis by comparing the protein expression of apoptosis, COX-1, and COX-2 in tumor tissues.

METHODS

The subjects were 36 patients who were FIGO stage IB uterine cervical cancer patients who underwent surgery at Ajou University Hospital. There were 12 cases with lymph node or parametrial involvement. All tissues were subjected to immunohistochemical staining for COX-1, -2, and TUNEL method for apoptosis detection, and the following results were obtained.

RESULTS

Tumor tissues confirmed by cytokeratin were separated into tumor surface, tumor stroma, and invasion site portions, in which decreased apoptosis was observed in the invasion sites. COX-2 expression was observed in all tumor tissues and was especially strong in the tumor invasion site. Therefore, it is suggested that COX-2 expression may suppress cell apoptosis at the tumor invasion site. When COX-2 expression was investigated according to the groups with regard to the presence of lymph node or parametrial involvement, there was a statistically significant (Mann-Whitney U test) COX-2 expression difference in the tumor invasion site (P value = 0.040) and the tumor stroma (P value = 0. 028).

CONCLUSIONS

In surgically treated stage IB cervical cancer patients, COX-2 was significantly expressed when lymph node or parametrial involvement was present. These results suggest that the expression of COX-2 in stage IB cervical cancer may downregulate apoptotic processes and thus enhance tumor invasion and metastasis.

Expression of leptin receptor (Ob-R) in human atherosclerotic lesions: potential role in intimal neovascularization

Neovascularization of the adventitial vasa vasorum with extension into the intima of atherosclerotic lesions is frequently observed, but its pathophysiological significance is still subject to debate. Recently, leptin, the product of the Ob gene, was identified. Leptin, via activation of the endothelial receptor (Ob-R), generates a growth signal involving a tyrosine kinase-dependent intracellular pathway and promotes angiogenic processes. We hypothesized that a high concentration of leptin within vasa vasorum and plaque itself, may influence inflammatory and vascular neovascularization coupling with functional upregulation of the vascular endothelial growth factor (VEGF). Microscopic computerized tomography was utilized for the spatial distribution of vasa vasorum and intimal neovascularization from atherosclerotic human coronary arteries. Atherosclerotic coronary arteries showed a dense plexus of microvessels in the adventitia and plaque itself. Microscopic analysis from human atherosclerotic aortas revealed an increase in the intimal thickness with neovascularization. The immunoreactivity for Ob-R, VEGF and matrix metalloproteinase (MMP) increased in atherosclerotic plaque, predominantly in the endothelial lining of the intimal neovessel and macrophages/foam cells. Our observation of a prominent colocalization between Ob-R, VEGF and MMP supports this hypothesis and these factors participate in the neovascularization of atherosclerotic lesions. The present study is the first report on vascular tissue and it opens a promising perspective concerning future investigations of leptin-dependent modulation of atherogenesis and vascular neovascularization under pathophysiolgical conditions.

Coexpression of cyclooxygenase-2 and matrix metalloproteinases in human aortic atherosclerotic lesions

Inflammation appears to have a major role in the development of atherosclerosis. Cyclooxygenase-2 (COX-2) is involved in the inflammatory response via the generation of prostanoids that, in turn, are involved in the production of matrix metalloproteinases (MMPs). This study aimed to investigate atherosclerosis in human aortas for in situ tissue distribution of COX-2, MMPs including MMP-9 and membrane type 1 MMP (MT1-MMP), and tissue inhibitor of metalloproteinase-2 (TIMP-2). Immunohistochemical studies were performed on atherosclerotic lesions of aortas from patients with aortic aneurysms (n = 4) and dissections (n = 3) by using antibodies to COX-2, MMP-9, MT1-MMP, and TIMP-2. Control tissues were obtained from traumatically dissected aortas (n = 2). All specimens from diseased aortas had atherosclerotic lesions ranging from fatty streak to atheromatous plaques. In control, there was no expression of COX-2, MMP-9, and MT1-MMP in all aortic layers. Immunoreactivity for COX-2 was predominantly noted in macrophages and smooth muscle cells (SMCs) of the intima including atherosclerotic plaque itself and the medial layer of the plaque base, as well as in SMCs and endothelial lining of the vasa vasorum in the adventitia. Immunoreactivity for MMP-9 and MT1-MMP was found in the same distribution as that of COX-2. Additionally, the expression of TIMP-2 increased in relation to MMP-9 expression. This study demonstrates that COX-2 is coexpressed with MMP-9 and MT1-MMP, not only by macrophages and SMCs in atherosclerotic lesions, but also in endothelial lining of the vasa vasorum of human aortas. Thus, vascular inflammatory reactions may influence extracellular matrix remodeling by coactivation of MMPs in the development of atherosclerosis and, in turn, the progression of disease.

Effects of low oxygen condition on the generation of reactive oxygen species and the development in mouse embryos cultured in vitro

OBJECTIVE(S)

To elucidate the relationship between intracellular H2O2 production and embryo development in different oxygen culture conditions.

METHODS

Pronuclear stage embryos were obtained from C57BL/CBA F1 and ICR mice. Measurement of H2O2 level was performed with 2',7'-dichlorodihydroflourescein diacetate and the number of blastomeres was counted after staining with 4',6'-diamidino-2-phenylindole.

RESULTS

Regardless of strains, H2O2 level reached a peak at the 2-cell stage in 20% O2. But in embryos cultured in 5% O2 it was significantly lower at the 2-cell and 4-cell stages compared to those from 20% O2. The embryos cultured in 20% O2 showed developmental delay or block, but in 5% O2 these phenomena were overcome and the development was significantly increased with an infrequent fragmentation.

CONCLUSIONS

Our data suggest that the 5% O2 decreases the relative concentration of H2O2 and results in improved embryo development in terms of quantity and quality without regard to type of strains.

Inducible nitric oxide synthase inhibitors from Melia azedarach var. japonica

In bioassay-guided search for inducible nitric oxide synthase (iNOS) inhibitory compounds from higher plants of South Korea, two beta-carboline alkaloids, 4-methoxy-1-vinyl-beta-carboline (1) and 4,8-dimethoxy-l-vinyl-beta-carboline (2) have been isolated from the cortex of Melia azedarach var. japonica. The structures of these compounds were elucidated on the basis of spectroscopic data. Compounds 1 and 2 showed marked inhibitory activity of iNOS on LPS- and interferon-gamma-stimulated RAW 264.7 cells.

Two new lignans from Lindera obtusiloba blume

Two new furanolignans (3, 5), together with three known lignans (1, 2, 4), were isolated from the stem of Lindera obtusiloba (Lauraceae). The structures of the compounds were determined as actifolin (1), pluviatilol (2), 5,6-dihydroxymatairesinol (3), (+)-syringaresinol (4), and (+)-9'-O-trans-feruloyl-5,5'-dimethoxylariciresinol (5) on the basis of physicochemical and spectroscopic evidences. Compounds 1, 2, 3, and 5 showed cytotoxicity against a small panel of human tumor cell lines with ED50 values of 3.40 to approximately 19.27 microg/ml.

A new epoxynaphthoquinol from Rumex japonicus

A new epoxynaphthoquinol derivative, 3-acetyl-2-methyl-1, 5-dihydroxy-2,3-epoxynaphthoquinol (I), was isolated from the root of Rumex japonicus. The structure was elucidated by high field 1D and 2D NMR techniques.

Two new monogalactosylacylglycerols from Hydrocotyle ramiflora

Two new monogalactosylmonoacylglycerols ( 1, 2) and two known compounds ( 3, 4) were isolated from Hydrocotyle ramiflora. Based on physicochemical evidence and spectral data, the structures of 1, 2, 3, and 4 were determined as (2 S)-1- O-(7 Z,10 Z,13 Z-hexadecatrienoyl)-3- O-beta-galactopyranosylglycerol, (2 S)-1- O-(9 Z,12 Z-octadecadienoly)-3- O-beta-galactopyranosyl-glycerol, alpha-spinasterol, and capsidiol 3-acetate, respectively.

Detection of reactive oxygen species (ROS) and apoptosis in human fragmented embryos

In human in-vitro fertilization (IVF)-embryo transfer, the in-vitro culture environment differs from in-vivo conditions in that the oxygen concentration is higher, and in such conditions the mouse embryos show a higher concentration of reactive oxygen species (ROS) in simple culture media. ROS are believed to cause damage to cell membranes and DNA fragmentation in somatic cells. This study was conducted to ascertain the level of H2O2 concentration within embryos and the morphological features of cell damage induced by H2O2. A total of 62 human oocytes and embryos (31 fragmented, 15 non-fragmented embryos, 16 unfertilized oocytes) was obtained from the IVF-embryo transfer programme. The relative intensity of H2O2 concentrations within embryos was measured using 2',7'-dichlorodihydrofluorescein diacetate by Quanti cell 500 fluorescence imaging and DNA fragmentation was observed with transmission electron microscopy and an in-situ apoptosis detection kit. The H2O2 concentrations were significantly higher in fragmented embryos (72.21 +/- 9.62, mean +/- SEM) compared to non-fragmented embryos (31.30 +/- 3.50, P < 0.05) and unfertilized oocytes (30.75 +/- 2.67, P < 0.05). Apoptosis was observed only in fragmented embryos, and was absent in non-fragmented embryos. Electron microscopic findings confirmed apoptotic bodies and cytoplasmic condensation in the fragmented blastomeres. We conclude that there is a direct relationship between increased H2O2 concentration and apoptosis, and that further studies should be undertaken to confirm these findings.

Detection of reactive oxygen species (ROS) and apoptosis in human fragmented embryos

In human in-vitro fertilization (IVF)-embryo transfer, the in-vitro culture environment differs from in-vivo conditions in that the oxygen concentration is higher, and in such conditions the mouse embryos show a higher concentration of reactive oxygen species (ROS) in simple culture media. ROS are believed to cause damage to cell membranes and DNA fragmentation in somatic cells. This study was conducted to ascertain the level of H2O2 concentration within embryos and the morphological features of cell damage induced by H2O2. A total of 62 human oocytes and embryos (31 fragmented, 15 non-fragmented embryos, 16 unfertilized oocytes) was obtained from the IVF-embryo transfer programme. The relative intensity of H2O2 concentrations within embryos was measured using 2',7'-dichlorodihydrofluorescein diacetate by Quanti cell 500 fluorescence imaging and DNA fragmentation was observed with transmission electron microscopy and an in-situ apoptosis detection kit. The H2O2 concentrations were significantly higher in fragmented embryos (72.21 +/- 9.62, mean +/- SEM) compared to non-fragmented embryos (31.30 +/- 3.50, P < 0.05) and unfertilized oocytes (30.75 +/- 2.67, P < 0.05). Apoptosis was observed only in fragmented embryos, and was absent in non-fragmented embryos. Electron microscopic findings confirmed apoptotic bodies and cytoplasmic condensation in the fragmented blastomeres. We conclude that there is a direct relationship between increased H2O2 concentration and apoptosis, and that further studies should be undertaken to confirm these findings.

Diagnosis of ovarian torsion with color Doppler sonography: depiction of twisted vascular pedicle

The purpose of this study was to assess the diagnostic value of ultrasonography for the detection of twisted vascular pedicle in ovarian torsion and to verify whether the blood flow alterations in the twisted vascular pedicle on color Doppler sonography can predict the viability of adnexal structures. In 28 of 32 patients with surgically proved torsion, the twisted vascular pedicle was detected preoperatively by ultrasonography, which shows a diagnostic accuracy of 87%. Arterial and venous flows were present in the twisted vessels on color Doppler sonography in 16 of 28 patients with a visible twisted vascular pedicle. In 11 patients who underwent adnexectomy, the pathologic findings revealed nonnecrotic ovaries in 10 patients. Untwisting of the twisted vascular pedicle was performed in five patients, and follow-up ultrasonography showed normal follicular development and ovulation. All 12 patients who showed no blood flow within the twisted vascular pedicle had necrotic ovaries. In conclusion, identification of the twisted vascular pedicle through ultrasonography is suggestive of ovarian torsion, and color Doppler sonography could be helpful in predicting the viability of adnexal structures by depicting blood flow within the twisted vascular pedicle.

Conservative therapy of adnexal torsion employing color Doppler sonography

STUDY OBJECTIVE

To ascertain if color Doppler sonography (CDS) can detect viability of adnexa in torsion.

DESIGN

Concurrent, nonrandomized study (Canadian Task Force classification II-2).

SETTING

Tertiary medical care center in a university hospital.

PATIENTS

Twenty-seven women suspected of having torsion of the ovary in which a benign tumor was present.

INTERVENTIONS

Color Doppler sonography of the ovarian pedicle suggested torsion. Laparoscopy or laparotomy was performed in 19 patients and confirmed the diagnosis.

MEASUREMENTS AND MAIN RESULTS

We identified a twisted vascular pedicle of the ovarian tumor by CDS in 24 (88%) of 27 women. Pedicle arterial and venous blood flow was observed in 10 women; pathology specimens revealed normal tissue, edema with congestion, or early hemorrhage. In all nine in whom only arterial blood flow or no blood flow was observed, pathology revealed hemorrhagic necrosis. In five women with arterial and venous blood flow the tumor was managed conservatively, either by detorsion or cystectomy, after which no embolism or tumor recurrence was seen at follow-up ultrasonography. Normal follicular development and ovulation occurred in these patients.

CONCLUSION

For women of childbearing age in whom torsion of benign adnexal tumors is suspected, CDS should be performed to confirm the diagnosis and ascertain whether or not pedicle arterial and venous blood flow is present. If such blood flow is detected, the adnexa is considered to be viable and detorsion or cystectomy may be performed, thus preserving the ovary. It is recommended that further studies with a larger group be undertaken to provide a basis for statistical analysis.

Identification of ovarian enhancer-binding factors which bind to ovarian enhancer 1 of the Drosophila genes yp1 and yp2

It has been reported that three different DNA regions-the fat body enhancer and ovarian enhancers 1 and 2-direct the tissue-specific expression of yp1 and yp2 in Drosophila melanogaster. In the present study, we identified ovarian enhancer 1-specific binding proteins. Electrophoretic mobility shift assay revealed that these proteins are present in the adult ovary, but not in adult testis or fat body. Southwestern blot analysis showed that about 130 kDa and 40 kDa proteins, designated OEF1 and OEF2, respectively, from ovarian nuclear or crude extracts bind specifically to the ovarian enhancer 1. The two proteins were partially purified by streptavidin/agarose-DNA affinity chromatography, and their binding activity was confirmed by electrophoretic mobility shift assay. These ovarian enhancer factors may play an important role in the regulation of transcription of yp1 and yp2 in the ovary.