Synergistic effect of ubiquitin on lipopolysaccharide-induced TNF-alpha production in murine macrophage cell line RAW 264.7 cells

Ubiquitin synergistically augmented the production of tumor necrosis factor alpha (TNF-alpha) in the presence of lipopolysaccharide (LPS) in murine macrophage cell line RAW 264.7. To investigate the mechanism of this augmentation, we analyzed the effect of ubiquitin during TNF-alpha mRNA synthesis and degradation, and TNF-alpha degradation on RAW 264.7 cells stimulated by LPS. It is found that ubiquitin augmented TNF-alpha mRNA synthesis. Ubiquitin did not affect the degradation of TNF-alpha mRNA and TNF-alpha. In the presence of LPS, extracellular accumulation of TNF-alpha by ubiquitin was twice than those by LPS, but intracellular accumulation of TNF-alpha produced by ubiquitin with LPS or by LPS had no difference. These data indicate that ubiquitin might induce TNF-alpha accumulation mainly by up-regulation of the TNF-alpha gene transcription. Although extracellular functions of ubiquitin remain largely unknown, we postulate that ubiquitin might be involved in the modulatory mechanisms of immune response.

Analysis of radiation pneumonitis and radiation-induced lung fibrosis in breast cancer patients after breast conservation treatment

We examined radiation pneumonitis in breast cancer patients after breast conservation treatment (BCT) and analysed the degree of radiation-induced lung fibrosis by computed tomographies of the chest (chest CT). Fifty-two breast cancer patients were treated with BCT, including breast irradiation and chemotherapy. These patients symptomatic of radiation pneumonitis were examined every two to four weeks. Chest X-rays and chest CT were performed about one year after irradiation. symptoms due to radiation pneumonitis was registered in 9.6% of patients. lungs showed fibrotic changes by chest CT in 90% of the cases. Concurrent or alternative chemotherapy increased the incidence of symptomatic radiation pneumonitis and, to a certain extent, the degree of fibrotic change in the lung after BCT.

The influence of lung cancer mass screening on surgical results

BACKGROUND

After the introduction of the mass screening program for lung cancer, the number of patients detected by mass screening increased as well as the number of early staged patients. Therefore, we examined the influence of lung cancer mass screening on surgical results.

METHODS

A total of 1177 primary lung cancer cases, who underwent surgery from 1963 to 1992, were retrospectively reviewed. They were grouped according to the changes in the mass screening system: the first period (1963-1977) before lung cancer screening started, the second period (1978-1986) when mass screening was conducted by the local government, and the third period (1987-1992) after the launching of the national screening program.

RESULTS

The rate of cases detected by mass screening increased over time and the 5-year survival rate improved significantly, from 33.7% in the first period, to 51.8% in the second period and finally, to 58.4% in the third period. The improvement is attributable to a relative increase of rate of stage I cases and better stage I survival rate. Specifically, in stage I cases, improvement resulted from a relative increase of stage IA in peripheral type and roentgenographically occult lung cancer cases and from better survival rate of these two groups.

CONCLUSION

As lung cancer screening has come into widespread use, detection of peripheral small-sized lung cancer and roentgenographically occult lung cancer have increased and consequently, surgical results have improved.

Introduction of NAD decreases fMLP-induced actin polymerization in chicken polymorphonuclear leukocytes--the role of intracellular ADP-ribosylation of actin for cytoskeletal organization

We reported previously that the arginine-specific ADP-ribosyltransferase in chicken polymorphonuclear leukocytes specifically modified actin, thereby inhibiting actin polymerization in vitro. In the present study, we investigated the effect of ADP-ribosylation on actin polymerization in situ. In the leukocytes, the introduction of NAD inhibited the increase in filamentous actin contents induced by a chemotactic peptide formyl-methionyl-leucyl-phenylalanine, while introduction of NAD together with novobiocin, a specific inhibitor for ADP-ribosyltransferase, did not. These results suggest that ADP-ribosylation regulates the formation of filamentous actin by the covalent modification of the protein in vivo.

An augmentation of Fas (CD95/APO-1) antigen induced by radiation: flow cytometry analysis of lymphoma and leukemia cell lines

An augmentation of Fas antigen induced by radiation was examined using flow cytometry. Six cell lines established from lymphomas or leukemias (HD-70, FLAM-76, CML-C-1, CML-C-2, DL-40 and DL-95) were used in this study. Each cell line was distributed to two dishes. The cells in one dish were irradiated at 10 Gy with cobalt-60 gamma rays. The control cells were not irradiated. At 6 h, 24 h, and 48 h after treatment, irradiated and non-irradiated cells of each cell line were stained with fluorescein isocyanate (FITC)-conjugated anti-human Fas antibody, and analyzed with flow cytometry. Mean fluorescence intensity (MFI) values of irradiated or non-irradiated cells were examined. MFI rates (MFI value of irradiated cells/MFI value of non-irradiated cells) of each cell line were calculated at each investigated time point, and an augmentation of the Fas antigen expression with radiation was evaluated. FLAM-76 did not express Fas antigen at any time. An augmented expression of Fas antigen due to irradiation was observed in the other five cell lines. These findings strongly suggest that radiation can augment Fas antigen expression in certain tumor cells. Further studies using Fas ligand or specific anti-Fas antibody are needed.

[Combination therapy of continuous venous infusion (CVI) of 5-FU and low dose consecutive cisplatin (CDDP), and the new oral anti-cancer drug S-1 for advanced gastro-intestinal cancer]

Highly effective treatment is required for patients with advanced GI cancer. Returning to the starting point for reconsideration of cancer chemotherapy, with the aim of attaining a therapy (self rescuing concept: SRC) with more potential efficacy and less toxicity than current therapy, we report two kinds of chemotherapy in the present paper. They were set up preclinically using the theory of 5-FU biochemical modulation, and demonstrated their usefulness in clinical practice. S-1 is a newly developed oral anti-cancer drug which is a combination of Tegafur (FT), a prodrug of 5-FU and two modulators (CDHP, an inhibitor of 5-FU degradation and Oxo, a selective inhibitor GI toxicity by 5-FU) at a molar ratio of 1:0.4:1. In combination with CDHP, 5-FU gradually released from FT remained longer in plasma, and consequently had high anti-tumor activity, while the combined Oxo significantly suppressed GI toxicity due to 5-FU. The response rate to S-1 of stomach cancer in a phase II study was 46.5% (60/129). Toxicity at more than G3 was less than 10%. In the combination therapy employing 5-FU by CVI (5-FU: 250-350 mg/body for 24 h, 4-6 wks) and low dose consecutive CDDP, CDDP acts mainly as a modulator of 5-FU (to increase 5-FU sensitivity for tumor by inhibition of intracellular Met incorporation). For this purpose, it was found that daily consecutive administration is required, even at low dose of CDDP (3-5 mg/body/day for 5 days). A high response rate (40-60%) was obtained for advanced GI cancer. Toxicity at more than G3 was less than 10%. On the other hand, the possibility has been suggested that so far as 5-FU is concerned, CVI every other day (500-750 mg/body/day for 3 days) is more favorable than long term CVI, with regard to decreasing GI and myelotoxicities based upon the difference in generation time between normal cell (GI mucous membrane and stem cell) and tumor cell cycles. The possibility is suggested that the above-mentioned chemotherapy can become a standard therapy for GI cancer.

Lipid A directly inhibits IL-4 production by murine Th2 cells but does not inhibit IFN-gamma production by Th1 cells

Lipopolysaccharide (LPS) is known to be an immunopotentiator but its effect on cytokine production by Th1 and Th2 cells is unknown. We found that high amounts of LPS, its lipid A moiety, and a lipid A analog all induced a decrease in IL-4 production and an increase in IFN-gamma production when given to keyhole limpet hemocyanin (KLH)-restimulated lymph node cells prepared from KLH-primed mice. Lipid A was similarly found to inhibit IL-4 production by purified CD4+ T cells and Th2 clones activated with immobilized anti-CD3epsilon and anti-CD28 antibodies, suggesting that the inhibition is not indirectly mediated through effects on antigen-presenting cells. No inhibitory effect of lipid A was observed on IFN-gamma production by a Th1 clone. Production of both IL-4 by the Th2 clones and IFN-gamma by the Th1 clone were inhibited by the immunosuppressive agent cyclosporin A. These findings indicate that lipid A can directly inhibit IL-4 production by CD4+ T cells without inhibiting the production of IFN-gamma. Lipid A may therefore become a useful tool to study the intracellular events that differentiate Th1 and Th2 cells.

The long-term survival rates of patients after repair of abdominal aortic aneurysms

This study was undertaken to examine the long-term survival rates of patients following abdominal aortic aneurysm (AAA) repair in comparison with an age-matched normal population, and to determine by multivariate analysis the factors influencing long-term survival. Of 125 patients who underwent AAA repair prior to July 1986, 13 died during hospitalization. Of these 13 patients, 6 who suffered aneurysmal rupture all died within 30 days. The survival rate of patients with ruptured aortic aneurysms was significantly lower than that of those with nonruptured aneurysms. Of the 112 patients surviving hospitalization, 85 died within 0.48 to 24 years after their operation. The long-term survival rate of patients who had suffered a preoperative cardiovascular event was significantly lower than that of those who had not suffered a preoperative cardiovascular event. The actual survival rate was significantly lower than the expected survival rate. According to a multivariate analysis, the significant predictors of late survival were age, aneurysmal rupture, and chronic renal failure in all the patients, and age, chronic renal failure, and pre- and postoperative cardiovascular events in patients who did not die in hospital. These findings indicate the importance of improving immediate perioperative management of ruptured AAA and that cardiovascular events should be prevented, or treated during long-term follow-up.

Effects of irradiation on telomerase activity in human lymphoma and myeloma cell lines

The effect of high-dose irradiation on telomerase activity was examined in some human lymphoma (DL40, DL95, DL110) and myeloma (U266) cell lines. The survival rate was reduced in DL40, DL110 and U266 by irradiation. Irradiation, however, showed no effect on the rate of DL95. Telomerase activity was detected in non-irradiated samples of all cell lines, as measured by PCR-based telomeric repeat amplification protocol assay. The telomerase activity increased 2-6.5 fold by irradiation. Especially in DL110, the activation increased in a dose-dependent manner. In the early phase after irradiation, we observed no correlation between telomerase activity and cell viability, suggesting that telomerase-mediated chromosome healing might not be a major cause and/or not sufficiently effective to protect the cells from irradiation.

Suppression of cell adhesion and spreading activities of fibronectin by arginine-specific ADP-ribosyltransferase from chicken polymorphonuclear leukocytes

Arginine-specific ADP-ribosyltransferase present in secretory granules of chicken polymorphonuclear leukocytes (so-called heterophils) was shown to be released into the extracellular space by secretagogues (Terashima et al., J. Biochem. 120 (1996) 1209-1215). In the present work, we examined fibronectin as an extracellular target protein of the released transferase. Fibronectin was ADP-ribosylated by purified transferase and stoichiometry of ADP-ribose incorporation into fibronectin was 1.0 mol/mol of fibronectin. Cell adhesion and spreading assays revealed that ADP-ribosylation of fibronectin markedly inhibited the adhesion activity of fibronectin. A proteolytic peptide map of ADP-ribosylated fibronectin demonstrated that the modification occurs in the cell binding domain of fibronectin. ADP-ribosylation of the RGD peptide suggests that the RGD sequence is the modification site in the domain. ADP-ribosylation of fibronectin in plasma means that fibronectin can probably serve as the substrate for extracellularly released ADP-ribosyltransferase in vivo. Thus, in the extracellular space, ADP-ribosyltransferase released from polymorphonuclear leukocytes may perhaps be involved in regulation of cell adhesion process by interfering with the activity of fibronectin.

Comparison of effects of ascorbic acid on endothelium-dependent vasodilation in patients with chronic congestive heart failure secondary to idiopathic dilated cardiomyopathy versus patients with effort angina pectoris secondary to coronary artery disease

Impaired endothelium-dependent vasodilation has been reported to play an important role in the pathogenesis of cardiovascular diseases such as coronary artery disease (CAD) and congestive heart failure (CHF). However, the precise mechanism of endothelial dysfunction has not been elucidated in these conditions. To evaluate the role of oxidative stress in endothelial dysfunction, the effect of antioxidant ascorbic acid on brachial flow-mediated, endothelium-dependent vasodilation during reactive hyperemia and nitroglycerin-induced endothelium-independent vasodilation was examined with high resolution ultrasound in 12 patients with CHF caused by idiopathic dilated cardiomyopathy without established coronary atherosclerosis and in 10 patients with CAD. Flow-mediated vasodilation in CHF (4.4+/-0.5%) and CAD (4.0 - 0.8%) was significantly (p <0.05) attenuated compared with that in 10 control subjects (9.6+/-0.9%). However, nitroglycerin-induced vasodilation was similar in 3 groups (13.7+/-1.3% in control, 13.9+/-1.1% in CHF, 12.7+/-1.4% in CAD). Ascorbic acid could significantly improve flow-mediated vasodilation only in patients with CAD (9.1+/-0.9%) but not with CHF (5.6+/-0.6%), and had no influence on nitroglycerin-induced vasodilation (13.6+/-1.1% in CHF, 14.0+/-1.3% in CAD). These results suggest that, in brachial circulation, augmented oxidative stress mainly leads to endothelial dysfunction in CAD but not in CHF caused by idiopathic dilated cardiomyopathy.

Loss of heterozygosity during the development and progression of differentiated adenocarcinoma of the stomach

In a recent allelotypic analysis of differentiated adenocarcinoma of the stomach, loss of heterozygosity (LOH) was found frequently on chromosomes 2q, 4p, 5q, 6p, 11q, 14q, 17p, 18q, and 21q. To clarify the sequence of these chromosomal losses during gastric carcinogenesis, microsatellite analysis of the chromosome arms described above was performed in 25 early and 29 advanced differentiated adenocarcinomas of the stomach. LOH on these chromosome arms fell within a range of 20-50 per cent. On 4p, 7q, 14q, 17p, and 21q, LOH was detected at a similar frequency in both early and advanced carcinomas, while LOH on 2q, 5q, 6p, 11q, and 18q was observed more than twice as frequently in advanced than in early lesions. Mean fractional allelic losses (FALs) were 0.221 in early and 0.413 in advanced carcinomas, representing a significant difference P < 0.05). These results suggest that LOH on 4p, 7q, 14q, 17p, and 21q is a relatively early event, while LOH on 2q, 5q, 6p, 11q, and 18q typically accumulates during the progression of gastric carcinogenesis.

Utilization of antipeptide antibodies as affinity ligands in immunoaffinity purification

Anti-peptide antibodies against the C-terminal regions of chimeric alpha-amylase, recombinant CD2 and insulin B-chain were obtained by using peptides corresponding to the C-terminal regions as immunogens. These anti-peptide antibodies adsorbed the native proteins, as well as the antigen peptides. The proteins were purified to high purity using the anti-peptide antibodies as affinity ligands. These ligands could discriminate the target proteins having different C-terminal regions. The adsorbed proteins were specifically eluted by the eluents containing the antigen peptides.

Changes of mutant-type p53 expression in squamous cell carcinoma of the head and neck during radiation therapy and its clinical significance: comparison of an immunohistochemical method and PCR-SSCP assay

P53 has been reported to be one of tumor suppressor genes that play a major role in signal transduction following many kinds of stresses, including ionizing radiation. Changes in p53 expression during radiation therapy in tumor tissues have not yet been reported. We determined whether radiotherapy changes p53 expression in human squamous cell carcinomas of the head and neck, and established the possible correlations between p53 expression and the therapeutic effects of radiation therapy. 30 patients with tumors of the oral cavity, oropharynx, and maxillary sinus were examined, and all the tumors were confirmed as squamous cell carcinomas. Biopsies were performed on the cancer tissues before treatment and at doses of 4, 10, and 20 Gy of radiotherapy, and the specimens were preserved in liquid nitrogen for further examination. Samples were immunohistochemically stained using streptoavidin-biotin peroxidase method and a monoclonal antibody against p53 (Ab-3, mutant type). For all the samples p53 PCR-SSCP (polymerase chain reaction-single strand conformation polymorphism) assays were performed. 14 of the 30 patients with squamous cell carcinomas showed expression of p53 in their tumor cells before and/or at 4 Gy or 10 Gy of radiotherapy. Eleven of the 14 tumors showed high radiosensitivity. Results of the p53 PCR-SSCP assays revealed mutations of p53 in 13 of 30 patients examined, and percentages of mutated p53 DNA varied at radiation doses of 4 Gy and 10 Gy. Ten of 12 patients with mutated p53 in their tumors showed decreased percentages of mutated p53 DNA during radiotherapy. The relationship between the immunohistochemical findings and the antitumor effect of a radiation dose of 20 Gy was examined on the correspondent hematoxylin-eosin sections. In patients whose p53 expressions in tumor cells were grades + or ++ or before radiotherapy and/or at 4 Gy of radiotherapy, the tumors responded significantly well to radiation therapy but the patients responded with significantly unfavorable clinical courses. The high radiosensitivity of squamous cell carcinomas in our samples could be explained by an overexpression of mutant type p53 in the tumor cells, and these mutant type p53-positive tumor cells possibly showed radioresponsiveness.

Changes in telomerase activity of advanced cancers of oral cavity and oropharynx during radiation therapy: correlation with clinical outcome

Telomerase activity has been evaluated for many kinds of malignancies, and it has been clarified that the activity reflected the malignant potential of the tumor. With regard to radiation therapy for cancer, simple and reliable assays for the prediction of therapeutic effect have not been fully developed yet. Therefore, we aimed to determine whether telomerase activity is changed by radiotherapy for advanced head and neck malignancies, and to clarify the possible correlation of telomerase activity with the therapeutic effect of radiation therapy and patients' clinical outcomes. Twenty-five patients with advanced cancers of the oral cavity and oropharynx were examined. All the cancers were confirmed histopathologically as squamous cell carcinomas. Biopsies were performed before treatment and at doses of 4 and/or 10 Gy, and 20 Gy of radiotherapy. To semi-quantitate telomerase activity, a highly sensitive PCR-based telomeric repeat amplification protocol assay was performed. Nineteen of the 21 cancers (90.1%) showed telomerase activity of varied extents prior to radiation therapy. Nine of the 25 patients showed continuous elevations of telomerase activity (> 10 TPG units/microg protein) in their tumors during radiation therapy, and these nine showed 13.8-216.9 TPG units/microg protein at 20 Gy of radiotherapy. In eight of the nine patients, tumors did not respond well to radiotherapy and relapsed locally in a short period after the treatment. On the other hand, in another group of 11 patients, who showed low (< 10) and/or no activity of telomerase in their tumors at 20 Gy of radiotherapy, there were nine patients whose tumors responded well to radiotherapy (p < 0.025 by the chi2 test). None of them relapsed locally in the follow-up period of approximately 21 months, and the difference was statistically significant (p < 0.025 by the chi2 test). It is concluded that the high activity of telomerase in tumor tissue at 20 Gy of radiotherapy can predict a poor therapeutic effect of radiation therapy and unfavorable patients' outcomes for advanced cancers of oral cavity and oropharynx.

Lymph node metastasis in small peripheral adenocarcinoma of the lung

OBJECTIVE

Our aim in this study is to clarify the clinical and pathologic features of small peripheral adenocarcinoma of the lung with special emphasis on intraoperative identification of lymph node metastasis.

PATIENTS AND METHODS

Between 1980 and 1996, 157 patients underwent lobectomy and complete hilar/mediastinal lymphadenectomy for small (1.1 to 2.0 cm in diameter) peripheral adenocarcinoma of the lung. The intraoperative assessment, the distribution of metastatic lymph nodes, and the association between the tumor's histopathologic characteristics and lymph node metastasis were retrospectively investigated in this study.

RESULTS

Postoperative examination revealed lymph node metastasis in 27 (17%) patients. Lymph node metastases were not noticed during the operation in 19 of these 27 patients. Metastases were localized in single lymph nodes in 10 patients; the metastases were distributed over a segmental, a lobar, an interlobar, and a mediastinal lymph node. The prevalence of lymph node metastasis was as follows: Of 92 patients with well-differentiated adenocarcinoma, seven (8%) had lymph node metastases; of the 65 patients with other types of tumors, 20 (31%) had lymph node metastases. Of 120 patients without pleural involvement, 13 (11%) had lymph node metastases; of the 37 with pleural involvement, 14 (38%) had lymph node metastases. Five-year survivals were estimated at 91% +/- 6% (mean +/- 95% confidence interval) for 130 patients with N0 tumor and 30% +/- 22% for 27 patients with N1 or N2 tumor.

CONCLUSIONS

Intraoperative assessment is not reliable for identifying lymph node metastasis. Lobectomy and complete hilar/ mediastinal lymphadenectomy are necessary to determine N stage rigidly. Histologic degree of differentiation and pleural involvement are significantly associated with lymph node metastasis.

[Severe pulmonary hypertension due to mitral regurgitation without overt sign of congestive heart failure: a case report]

A 49-year-old man was found to have a heart murmur at a local hospital and was referred to our hospital for further examination. Although he had no signs of congestive heart failure, echocardiography and cardiac catheterization showed severe pulmonary hypertension caused by severe mitral regurgitation. Mitral valve replacement was performed, followed by reduction of pulmonary artery pressure. This patient had an unusual combination of no signs of lung congestion despite severe mitral regurgitation with pulmonary hypertension.

[Pharmacokinetic analysis of low-dose intra-peritoneal cis-platinum administration]

Pharmacokinetic parameters after intra-peritoneal administration of low-dose cis-platinum (CDDP) were analysed in order to evaluate the possibility of applying low-dose 5-FU/CDDP therapy (1-FP) for outpatients. Four patients with advanced gastric cancer were the subjects of this study. CDDP at a dose of 20 mg/body was administered intra-peritoneally, and peripheral venous blood was collected at 30 min, 4, 8, 24, 48, 72, 96 and 120 hr after drug administration. The plasma platinum (Pt) concentration was determined by atomic absorption spectrometry. Pharmacokinetic parameters were calculated using a two-compartment open model. C max, AUC, t1/2 alpha and t1/2 beta of total-Pt were 1. 27 +/- 0.21 micrograms/ml, 95.28 +/- 16.93 micrograms.hr/ml, 1.91 +/- 0.76 hr and 190.2 +/- 125.6 hr, respectively. Total-Pt concentration at 120 hr, after administration was 0.54 +/- 0.14 microgram/ml. This result suggests that intraperitoneal low-dose CDDP administration is a promising method for 1-FP therapy for outpatients, because the plasma total-Pt level is maintained at a sufficiently high level for a long period.

Carcinoembryonic antigen level in peritoneal washing is a prognostic factor in patients with gastric cancer

This study was designed to evaluate the usefulness of carcinoembryonic antigen (CEA) and sialyl-Tn antigen (STN) levels in peritoneal washings in gastric cancer patients. At the time of laparotomy, peritoneal washings were collected from 96 gastric cancer patients and CEA and STN levels were determined. Patients with elevated CEA (100 ng/g protein) had a high incidence for peritoneal metastasis, lymph node metastasis and serosal invasion. In addition, prognosis in patients with high CEA level was significantly poorer than in those without it. The peritoneal CEA is a prognostic factor in patients with gastric cancer.

Clinical analysis of small-sized peripheral lung cancer

OBJECTIVE

In Japan, with the initiation of the lung cancer screening program, small-sized peripheral lung cancer in which the diameter is 2 cm or less has been increasing. The purpose of this study is to determine the clinicopathologic behavior of small-sized lung cancer.

METHODS

Four hundred ninety-six patients with cT1 N0, peripheral, resected non-small-cell lung cancer, who were operated on between 1980 and 1996, were selected, grouped by tumor diameter or histologic type, and then analyzed for clinicopathologic behavior. On the basis of measured diameter roentgenographically, the patients were divided into two groups; group c-S with lesions 2 cm or less in diameter and group c-L with lesions 2.1 to 3 cm in diameter.

RESULTS

Lymph node metastasis was recognized in 18% of group c-S, in 23% of group c-L, and in 21% for the entire clinical group. The rate of those with the progressive state was 19% in group c-S and 26% in group c-L. The 5-year survival was 79.5% in group c-S and 69.3% in group c-L (i.e., there was a significant difference between the two groups).

CONCLUSION

Compared with the patients with lesions 2.1 to 3 cm in diameter, the patients with small-sized lung cancer had a milder progressive state and a better prognosis.

Loss of heterozygosity during the development and progression of differentiated adenocarcinoma of the stomach

In a recent allelotypic analysis of differentiated adenocarcinoma of the stomach, loss of heterozygosity (LOH) was found frequently on chromosomes 2q, 4p, 5q, 6p, 11q, 14q, 17p, 18q, and 21q. To clarify the sequence of these chromosomal losses during gastric carcinogenesis, microsatellite analysis of the chromosome arms described above was performed in 25 early and 29 advanced differentiated adenocarcinomas of the stomach. LOH on these chromosome arms fell within a range of 20-50 per cent. On 4p, 7q, 14q, 17p, and 21q, LOH was detected at a similar frequency in both early and advanced carcinomas, while LOH on 2q, 5q, 6p, 11q, and 18q was observed more than twice as frequently in advanced than in early lesions. Mean fractional allelic losses (FALs) were 0.221 in early and 0.413 in advanced carcinomas, representing a significant difference P < 0.05). These results suggest that LOH on 4p, 7q, 14q, 17p, and 21q is a relatively early event, while LOH on 2q, 5q, 6p, 11q, and 18q typically accumulates during the progression of gastric carcinogenesis.

Induction of DNA fragmentation by total-body irradiation in murine liver

Total-body irradiation (TBI) is an accepted modality to treat patients with disseminated tumors. The influence of the treatment on normal tissues is evaluated using mice by measuring the rate of the induction and distribution of apoptosis, as well as DNA fragmentation which occurs in the murine liver within hours of irradiation. Unanesthetized female C3H/He mice were exposed to gamma-ray TBI of 2, 7, and 20 gray (Gy) delivered from 60Co at a dose rate of 114 cGy/min. Frozen sections of livers which were excised from the animals at various times after irradiation were stained by hematoxylin-eosin (H-E) to count numbers of apoptotic cells, or were examined to detect DNA fragmentation. The percentages of apoptotic cells and length of the period during which the maximum levels of the percentages were exhibited showed a dose-dependent increase in the sections stained with H-E. No positive cells for 3'-OH ends of fragmented DNA were found in the liver before TBI, whereas positive cells were observed immediately after irradiation without dose-dependency, these positive cells returned to nearly basal levels after several hours. Positive cells were observed prior to showing apoptosis, suggesting that DNA fragmentation occurs immediately after TBI independent of apoptosis. The difference in the time courses between induction of DNA fragmentation and of apoptosis was not observed in other organs or in the samples treated with the detergent. These results suggested that the 3'-OH ends newly generated by TBI were masked by a detergent-soluble DNA-binding molecule which might be preferentially present in the murine liver.

Pharmacokinetics of cisplatin in combined cisplatin and 5-fluorouracil therapy: a comparative study of three different schedules of cisplatin administration

BACKGROUND

Cisplatin is widely used in combination chemotherapy against a variety of tumors; however, the optimal administration schedule of cisplatin is still controversial. To clarify the pharmacokinetic differences according to the administration schedules of cisplatin, we compared three different administration schedules of cisplatin such as single short-term infusion, daily short-term infusion and daily continuous infusion in combination with 5-fluorouracil. Preliminary clinical responses and toxicities were also investigated.

METHODS

A total of 12 courses in combination of cisplatin and 5-fluorouracil therapy was studied. The schedules of cisplatin tested were as follows: single short-term infusion (80 mg/m2, day 1,2 h div., n = 4), daily short-term infusion (20 mg/m2, days 1 to 5, 2 h div., n = 4), daily continuous infusion (100 mg/m2, 120 h, n = 4). In all schedules, 5-fluorouracil was continuously administered at a dose of 800 mg/m2/day on days 1 to 5. The area under the time-concentration curve (AUC) and the maximum concentration (Cmax) of total and free Pt were investigated.

RESULTS

The highest AUC of total and free Pt and the lowest Cmax of free Pt were observed in the daily continuous infusion (total AUC; 162.53 +/- 18.39 micrograms h/ml, free AUC; 5.50 +/- 0.9 micrograms h/ml, free Cmax; 0.07 +/- 0.01 microgram/ml, mean +/- SEM). Two patients in the single short-term infusion and one patient in the daily continuous infusion indicated partial responses clinically. No nephrotoxicity or ototoxicity was observed. All toxicities were mild and tolerable in all regimens; however, the incidence of GI toxicity in daily continuous infusion seemed to be relatively higher.

CONCLUSIONS

Daily continuous infusion of cisplatin gave the best pharmacokinetic results and to evaluate the clinical advantage of this schedule a prospective randomized trial should be conducted with sufficient numbers of patients.

Establishment and characterization of a new human extrahepatic bile duct carcinoma cell line (ICBD-1)

A new human extrahepatic bile duct carcinoma cell line (ICBD-1) was established from surgically resected tumor of a 71-year-old Japanese male patient. ICBD-1 cells proliferate in a layer with a population doubling time of 31.5 h and secrete tissue polypeptide antigen. ICBD-1 cells have a tetraploid pattern with a DNA index of 1.83 and chromosome counts showed equally distribution in a range from 65 to 69. IC50 values for ICBD-1 cells were 200 ng/ml for adriamycin, 400 ng/ml for mitomycin C, 2 microg/ml for cisplatin and 300 ng/ml for 5-fluorouracil. ICBD-1 cells were successfully transplanted to male nude mice, inducing progressive tumor growth. Histologically, nude mouse tumors were less differentiated than the original human tumor. Tumor cells showed alveolar structures with thin fibrous stroma, classified as poorly-differentiated adenocarcinoma. ICBD-1 is the fourth established cell line that originate from extrahepatic bile duct carcinoma and it will be applicable for the experimental studies of this disease.