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991.
Yoshihiro Kikuchi Junko Hirata Kenji Yamamoto Kenji Ishii Tsunekazu Kita Kazuya Kudoh Takehiko Tode Ichiro Nagata Ken Taniguchi Michihiko Kuwano 《Cancer science》1997,88(2):213-217
This study was designed to elucidate the mechanisms of cisplatin (CDDP) resistance using two human ovarian cancer cell lines, KF and TYK, and two CDDP-resistant lines, KFr and TYK/R, derived from the former lines. KFr and TYK/R showed about 3-fold higher resistance to the cytotoxic effects of CDDP than their parental lines. They also showed a significant increase in sensitivity to not only etoposide, but also (+)-(4S)-4, ll-diethyl-4-hydroxy-9-[(4-piperidino-piperidino)carbonyloxy]-l H -pyrano[3',4':6,7]inodolizino[l,2- b ]quinoline-3,14(4 H , 12 H )-dione hydrochloride trihydrate (CPT-11). Cellular CDDP accumulation levels in KFr and TYK/R were decreased from those of the parental cells. By contrast, the cellular glutathione (GSH) content in KFr cells was 1.7-fold higher than that in KF, whereas TYK/R cells had a 40% lower content than TYK cells. Cellular mRNA levels of drug-resistance-related genes, such as DNA topoisomerase (topo) I and topo II, glutathione S-transferase-π (GST-π;), γ-glutamylcysteine synthetase (.γ -GCS ), and metallothionein ( hMT ) genes, were compared between drug-sensitive KF or TYK and KFr or TYK/R. KFr cells had 8.5- and 24.7-fold higher mRNA levels of γ-GCS and topo II genes than KF cells while KFr had only a slight increase in GST-π mRNA level as compared with KF. By contrast, TYK/R cells had 2.9- and 1.7-fold higher hMT and topo I mRNA levels than TYK cells. Acquisition of CDDP resistance in human ovarian cancer cells thus appeared to be related mainly to expression of γ -GCS, topo II and hMT genes, and partly to that of topo I and GST-π genes, in addition to a decrease in CDDP accumulation 相似文献
992.
Toshio Imai Yoshikazu Tanaka Kenji Fukudome Shin Takagi Koichi Araki Osamu Yoshie 《International journal of cancer. Journal international du cancer》1993,55(5):811-816
Previously, we studied the surface expression of LFA-1 (CD 11 a/CD 18) and ICAM-1 (CD54) in a panel of 16 human T-cell lines and found that those carrying HTLV-1 pro-viruses expressed high levels of ICAM-1. Enhanced expression of ICAM-1 was also seen in fresh leukemic cells from ATL patients. In the present study, we systematically examined the surface expression of 19 different cell-adhesion molecules (CAMs) (the immunoglobulin superfamily, the homing receptors, the integrins, etc.) in a panel of 20 human T-cell lines (6 HTLV-1-negative lines and 14 HTLV-1-positive lines). The surface expression of LFA-3 (CD58) was constantly enhanced in HTLV-1-positive T-cell lines except for MT-1, an ATL-derived cell line, which was devoid of a number of CAMs including ICAM-1. LFA-3 proteins and mRNA were found at strongly increased levels in HTLV-1 -positive T-cell lines. 相似文献
993.
994.
Cytokines Induce Uridine Phosphorylase in Mouse Colon 26 Carcinoma Cells and Make the Cells More Susceptible to 5'-Deoxy-5-fluorouridine 总被引:2,自引:2,他引:2
Hiroyuki Eda Kaori Fujimoto Shin-ichi Watanabe Tohru Ishikawa Toshio Ohiwa Kenji Tatsuno Yutaka Tanaka Hideo Ishitsuka 《Cancer science》1993,84(3):341-347
The antiproliferative activity of 5-fluorouracil (5-FUra) and 5'-deoxy-5-fluorouridine (5'-dFUrd), used in combination with typical cytokines and growth factors, was investigated in mouse colon 26 carcinoma cells. Tumor necrosis factor α (TNFα), interleukin-1a (IL-1α), and interferon γ (IFNγ) at low doses showing < 50% inhibition of cell growth by themselves enhanced the susceptibility of the cells to the activity of 5'-dFUrd. In particular, a mixture of these cytokines greatly enhanced the activity of 5'-dFUrd and 5-FUra by up to 12.4- and 2.7-fold, respectively, whereas the activity of other cytostatics was only slightly changed (< 1.5-fold). Basic fibroblast growth factor also increased the susceptibility, but only to 5'-dFUrd. This preferential enhancement of the activity of 5'-dFUrd would be due to induction by the cytokines of uridine phosphorylase (Urd Pase), by which 5'-dFUrd is converted to 5-FUra. TNFα, IL-1α, IFNγ, and a mixture of these factors increased the enzyme activity by up to 3.7-fold in colon 26 cells. Consequently, the anabolism of 5'-dFUrd to fluoronucleotides and the incorporation of 5-FUra into RNA in colon 26 cells were increased by TNFα treatment. In addition, the increase by the cytokine mixture in the susceptibility to 5'-dFUrd was abolished by an inhibitor of Urd Pase, 2,2'-anhydro-5-ethyluridine. These results indicate that induction of Urd Pase activity by cytokines is a critical event that increases the susceptibility to 5'-dFUrd. 相似文献
995.
Enhancing Effects of Estrogens on Endometrial Carcinogenesis Initiated by N-Methyl-N-nitrosourea in ICR Mice 总被引:1,自引:3,他引:1
Kenji Niwa Toshiko Murase Tatsuro Furui Shigeo Morishita Hidehiro Mori Takuji Tanaka Hideki Mori Teruhiko Tamaya 《Cancer science》1993,84(9):951-955
The present study was undertaken to examine the effects of estrogens, such as estrone (E1), 17β-estradiol (E2) and estriol (E3), on endometrial Carcinogenesis initiated by N-methyl-N-nitrosourea (MNU) in mice. A total of 120 female ICR mice received MNU solution (1 mg/100 g body wt.) and normal saline at 10 weeks of age into their left and right uterine corpora, respectively. One week later, they were divided into four groups and treated as follows: Group 1 (30 mice) was given 25 ppm E1-containing diet; Group 2 (30 mice) was fed 5 ppm E2-containing diet; Group 3 (30 mice) was given 25 ppm E3-containing diet; and Group 4 (30 mice) was fed the basal diet alone. At the termination of the experiment (Week 30), all surviving animals were autopsied and histopathological examinations revealed that endometrial adenocarcinomas had developed in all groups. The incidence of adenocarcinomas in the MNU-treated uterine corpus in Group 1 (25 ppm E1-feeding, 9/23, 39%) was significantly higher than that in Group 4 (basal diet, 3/26, 12%, P<0.05). Also, the incidences of adenocarcinomas in the MNU-treated uterine corpus in Groups 2 (5 ppm E2-feeding, 8/24, 33%) and 3 (25 ppm E3-feeding, 7/26, 28%) were higher than in Group 4, but the difference was not statistically significant. Feeding of diet containing E1, E2 and E3 increased the incidences of the preneoplastic endometrial lesions (atypical, adenomatous or cystic glandular hyperplasia). In the uterine cervix, small numbers of squmous cell carcinomas, dysplasias or hyperplasias were occasionally found in all groups. These results indicate enhancing effects of the above three types of estrogens on the endometrial carcinogenesis induced by MNU in ICR mice. 相似文献
996.
Taketoshi Suehiro Teruyoshi Ishida Kenji Sugio Keizo Sugimachi Katsuo Sueishi 《Journal of surgical oncology》1993,54(1):51-56
Monoclonal antibody KP16D3 recognizes a 60 kDa protein associated with mucin-nonproducing papillary adenocarcinoma, especially that originating from nonciliated bronchiolar epithelial cells of the lung. We immunohistochemically examined 56 primary lung adenocarcinomas using the monoclonal antibody KP16D3. Of these tumors, 31 (55%) were positive for KP16D3 immunoreactivity. The disease-free survival rates showed no statistical differences between KP16D3-positive and KP16D3-negative patients. However, in stage I and T1 disease, the disease-free survival rates of KP16D3-positive patients were statistically lower than those of KP16D3-negative patients (P < 0.05). These findings suggest that KP16D3 may be useful as a prognostic marker for patients with stage I primary lung adenocarcinoma. Conversely, use of this marker and subtyping of lung adenocarcinomas reflect the prognosis of the disease. © 1993 Wiley-Liss, Inc. 相似文献
997.
Dr. Yukiko Suzuki Kenji Harada Yasunori Miura Wataru Sato Kiyoshi Hayasaka Koichi Kawamura Goro Takada 《Pediatric cardiology》1993,14(3):162-166
Summary Mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) are known to be associated with cardiomyopathy. Systolic and diastolic left ventricular functions were assessed by M-mode and Doppler echocardiography in four patients with MELAS and in 14 normal controls. The interventricular septal thickness and left ventricular posterior wall thickness were greater (11.0±1.6 mm vs. 5.8±0.7 mm and 11.0±2.2 mm vs. 5.9±0.8 mm) in patients with MELAS than in a control group. Parameters of systolic left ventricular functions (ejection fraction, shortening fraction, systolic time intervals, and mean Vcf) and left ventricular dimensions were not significantly different between the two groups. To assess the diastolic function, blood flow velocity across the mitral valve was measured by Doppler echocardiography and various indexes were obtained. In patients with MELAS, the impairment of diastolic left ventricular filling was demonstrated by decrease in the following indexes: peak flow velocity in the early passive filling period (E) (0.76±0.10 m/s vs. 0.94±0.09 m/s), integrated velocity for total E (10.2±1.3 vs. 13.0±0.9), the ratio of E and late atrial filling integrated velocities (1.72±0.06 vs. 2.49±0.29). 相似文献
998.
Yoji Yamazaki Tsuginori Yoshida Ryoji Mizuno Shoji Yuno Akihiko Hara Jyoji Yoshizawa Kenji Sakurai 《Pediatric surgery international》1994,9(5-6):455-456
Pre- and postoperative blood counts were retrospectively compared between patients with no hemostatic management (group A,n = 30) and patients with a fibrin adhesive (Beriplast P) applied to the cut edges (group B,n = 8) when pyloromyotomy was performed for hypertrophic pyloric stenosis. Postoperative red blood cell count, hematocrit, and hemoglobin were significantly decreased in group A (P <0.01) while there was no significant change in group B. It has been stated that the Ramstedt operation does not require any special hemostatic management. However, as postoperative peritoneal bleeding is suspected, hemostatic management with a fibrin adhesive applied to the incised region of the serosa and muscle layer is recommended. 相似文献
999.
Yasushi Takahashi Kenji Harada Akira Ishida Masamichi Tamura Goro Takada 《Archives of disease in childhood. Fetal and neonatal edition》1994,71(2):F118-F121
The left ventricular Frank-Starling response was studied in 15 preterm infants, less than 1500 g birth weight, and in 16 fullterm infants with patent ductus arteriosus. Left ventricular end diastolic volume (LVEDV), stroke volume, and cardiac output were calculated from biplane echocardiographic images with a modified Simpson's rule, and the left ventricular function curve was obtained by standardising with birth weight and body length. In the relationship between LVEDV and stroke volume, the slope of the regression line was significantly milder in preterm than in fullterm infants; however, there was no significant difference in the relationship between LVEDV and cardiac output. The heart rate was significantly higher in preterm than in fullterm infants. Our data indicated that the premature infants had less left ventricular reserve capacity to respond to the increased preload through the left-to-right ductal shunting than the mature ones, and that the high pulse rate made it possible to generate adequate cardiac output in premature infants. 相似文献
1000.
Combination of nedaplatin and vindesine for treatment of relapsed or refractory non-small-cell lung cancer 总被引:5,自引:0,他引:5
Takigawa N Segawa Y Ueoka H Kiura K Tabata M Shibayama T Takata I Miyamoto H Eguchi K Harada M 《Cancer chemotherapy and pharmacology》2000,46(4):272-278
Purpose: A phase II study of nedaplatin and vindesine was conducted to evaluate their efficacy and safety for treatment of relapsed
or refractory non-small-cell lung cancer (NSCLC). Methods
: Between August 1996 and September 1998, 48 patients who had previously received chemotherapy, thoracic radiotherapy, and/or
surgery were enrolled in the study. Patients were required to have an Eastern Cooperative Oncology Group performance status
of 0 to 2 and an age between 20 and 79 years. Treatment consisted of nedaplatin (80 mg/m2, day 1) and vindesine (3 mg/m2, days 1 and 8) every 3 to 4 weeks. Results: Of 48 patients, 7 (14.6%) exhibited an objective response. Four (50%) of eight chemotherapy-naive patients had a partial
response. However, of the 40 patients who had received prior chemotherapy, a partial response was observed in only 3 (7.5%).
At a median follow-up time of 85.1 weeks, the median survival time was 43.6 weeks (95% confidence interval 34.4–52.7) for
patients who had received chemotherapy, with a survival rate of 40% at 1 year. Grade 3 or 4 neutropenia occurred in 43 of
48 patients (90%), and neutropenic fever was observed in 3 of the 43 patients, one of whom died of sepsis. Pharmacokinetic
and pharmacodynamic analyses of platinum were performed in 43 patients during the first cycle of chemotherapy. Percent reduction
in absolute neutrophil count was correlated not only with the area under the plasma ultrafilterable platinum concentration
versus time curve (r=0.41, P=0.007) but also with the duration of ultrafilterable platinum concentration above 1 μg/ml (r=0.41, P=0.007). Patients with progressive disease exhibited a shorter duration of ultrafilterable platinum concentration over 1 μg/ml
(P=0.046) than those with other responses. Conclusion: A combination of nedaplatin and vindesine was unsatisfactory as second-line chemotherapy for NSCLC, although the combination
was well tolerated. The duration of ultrafilterable platinum concentration above 1 μg/ml was an important pharmacokinetic
parameter for predicting both chemotherapy-induced neutropenia and treatment outcome.
Received: 4 November 1999 / Accepted: 28 April 2000 相似文献