Biomedical subjects

N Saijo

Publications and source records attributed to N Saijo.

At least 271 records · Page 15Linked to original sources

PubMed1991

[The relation between myelotoxicity and performance status or aging in chemotherapy of non-small cell lung cancer].

One hundred eighty six patients of non-small cell lung cancer treated with cisplatin-based chemotherapy were analyzed. Significant incidence of anemia was observed in PS 2-3 patients as compared to PS 0-1 cases. Incidence of thrombocytopenia was significant in cases 70 or more years old as compared those less than 50 years old. No correlation was detected between myelotoxicity and aging.

Aged↗

PubMed1991

[Preclinical trials from the standpoint of clinical trials].

The establishment of reliable preclinical test is essential for the reasonable clinical trial. As a methodology for the screening of new active anticancer agents, disease oriented strategy using human tumor cell lines has been proposed in USA. The important questions in DOS are to determine the representative cell lines of specific cancer and it is also extremely important to decide the numbers of cell lines used for the screening. CPT-11, topoisomerase I inhibitor, developed in my country has been demonstrated to be active against lung cancer cell lines compared with mice tumors such as S-180 and P-388. However, no compound is demonstrated to be clinically active so far by this methodology. The criteria for the application of clinical trial are obscure and each drug company decides empirically by themselves. We have proposed to use PEI (predictive efficacy index) for the prediction of antitumor activity of new compounds. The clinical effect of new platinum analogue well correlated with this value. We have conducted phase II trial of 5-FU + LV against NSCLC without no prior chemotherapy. No responder was observed in the trial. Augmentive effect of leucovorin on the cytotoxicity of 5-FU and FdUrd was examined in vitro against NSCLC and colon cancer cell lines. Leucovorin stimulated the cytotoxicity of both drugs only against colon cancer cell lines. We tried to predict the response rate of new platinum derivative based on the data of bioassay of patient's serum administrated with platinum compounds. The predicted response rates of 254-S were 57-67% and 16-27% against SCLC and NSCLC, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1991

[Resistance to anticancer drugs in NIH3T3 cells transfected with c-myc and/or c-H-ras genes].

NIH3T3 cells transfected with c-H-ras and/or c-myc genes were examined for differences in drug sensitivity. The two transfectants used were NIH3T3-nm-1 (nm-1), pT22-3-nm-2. They were transfected with c-myc, c-myc plus activated c-H-ras, respectively. The relative resistances (IC50 values of transfectants/those of NIH3T3 cells) to cisplatin, adriamycin, 4-hydroperoxycyclophosphamide, melphalan, and CPT-11 were 2.1, 1.6, 4.7, 4.9, 1.6, respectively for nm-1 and 1.6, 2.2, 3.3, 9.1 and 2.2, respectively for nm-2. These results strongly suggest that the expression of the c-myc gene plays a role for the acquisition of drug resistance. The c-myc gene is believed to provide us an important clue for determining the mechanism of drug resistance.

Antineoplastic Agents↗

PubMed1991

The development of a treatment model for lymph node metastasis in nude mice transplanted with rat fibrosarcoma clone A.

We have tried to establish a model for lymph node metastasis in nude mice transplanted with clone A of methylcholanthrene-induced rat fibrosarcoma. Tumor cells transplanted either subcutaneously or intrafootpad metastasized exclusively to the lymph nodes in nude mice treated with antiasialo GM1 antiserum. In the experiments of intrafootpad transplantation, all the mice died of disseminated lymph node metastasis if the leg was not resected, or was resected more than 3 weeks after the transplantation of clone A. Some mice whose legs were amputated 1 or 2 weeks after transplantation could be cured by amputation alone. The maximum effective dose of in vitro active drug could improve the survival in mice, and 3/5, 4/5, and 3/5 mice treated with MMC, ACNU and CDDP respectively were cured even if their legs were amputated 3 weeks after transplantation. This tumor-bearing animal system was considered to provide a valuable experimental model for lymph node metastasis.

Amputation, Surgical↗

PubMed1990

Establishment of a camptothecin analogue (CPT-11)-resistant cell line of human non-small cell lung cancer: characterization and mechanism of resistance.

Camptothecin-11 (CPT-11) is a new derivative of camptothecin, a plant alkaloid antitumor agent, and a good candidate for clinical trials because of higher antitumor activity, less toxicity, and high aqueous solubility. CPT-11 is known to be altered into an active form, SN-38, by esterase in in vivo. CPT-11-resistant cells (PC-7/CPT) established from a human non-small cell lung cancer cell (PC-7) by stepwise, continuous treatment with CPT-11 exhibit about a 10-fold increase in resistance to the drug. CPT-11-resistant cells show a moderate cross-resistance to camptothecin (x8.6) and SN-38 (x8.6), and weak cross-resistance to Adriamycin (x2.2) and 5-fluorouracil (x2.4). The comparative studies between the parent (PC-7) and resistant (PC-7/CPT) cell lines with respect to their growth characterization shows a longer cell doubling time (45.8 versus 35.5 h), a lower cloning efficiency (3.2 versus 7.1%), and a lower population of S-phase cells (26.4 versus 36.0%) in the CPT-11-resistant cells. This observation may partly explain the resistance to CPT-11, a drug whose activity is cell cycle specific. Accumulation of CPT-11 is nearly the same in both cell lines. However, the intracellular concentration of SN-38 formed in the parent cells was 2-fold greater than in the CPT-11-resistant cells. This alteration may affect to some extent to the resistance. As assayed by relaxation of supercoiled plasmid DNA, the total activity of DNA topoisomerase I from the CPT-11-resistant cells was shown to be reduced to one-fourth its level in sensitive cells. The reduced activity was caused by a reduction of amount of DNA topoisomerase I. Furthermore, the enzyme from the resistant cells was shown to be 5-fold more resistant to CPT-11 than the enzyme from the parent cells. Thus, decreased total activity of topoisomerase I may play an important role in cellular resistance to CPT-11, and it appears that this decreased activity is due to a resistant form of topoisomerase I in CPT-11 resistant cells.

Antineoplastic Agents, Phytogenic↗

PubMed1990

Decreased accumulation as a mechanism of resistance to cis-diamminedichloroplatinum(II) in human non-small cell lung cancer cell lines: relation to DNA damage and repair.

The mechanism of resistance to cis-diamminedichloroplatinum(II) (CDDP) is still controversial, although several kinds of processes have been proposed. For elucidation of the mechanism of CDDP resistance in CDDP-resistant human non-small cell lung cancer cells (PC-9/0.5, 7.1-fold resistant), we examined the formation of DNA interstrand cross-links (ICL), one kind of DNA damage induced by CDDP, its repair, and intracellular accumulation of CDDP. We measured the frequency of CDDP-induced ICL by means of the alkaline elution technique and the amount of intracellular platinum for intracellular accumulation of CDDP by means of atomic absorption spectrophotometry in PC-9 (parental cell) and PC-9/0.5 cells. Formation of ICL in PC-9 cells exposed to 5 micrograms of CDDP per ml for 6 h was 5.85 times that in PC-9/0.5 cells. On the other hand, the ability to repair CDDP-induced ICL was identical in both cell lines. Intracellular accumulation studies revealed that PC-9 retained 5.07 times as much platinum as that in PC-9/0.5 after 3-h exposure to CDDP. It was conjectured that the decrease in the intracellular accumulation of CDDP might be the main cause of CDDP resistance in PC-9 cells, since the decreased accumulation was paralleled by the decreased level of ICL.

Carcinoma, Non-Small-Cell Lung↗

PubMed1990

Glutathione-S-transferase pi as a determinant of drug resistance in transfectant cell lines.

A series of glutathione S-transferase pi (GST-pi) transfectant cell lines have been constructed in activated c-H-ras-transformed NIH-3T3 cells (pT22-3) by using a pKOneo plasmid and an expression vector containing cDNA for GST-pi with a beta-actin gene promoter. From the wild type pT22-3 cells, two clones were selected and designated RGN1 and RGN2. The degree of overexpression of GST-pi was estimated by Northern and Southern blot analysis to be incrementally higher in RGN2 compared with RGN1. Translation of mRNA was estimated by Western blot analysis using isozyme-specific polyclonal antibodies and confirmed the relative GST-pi levels. Each cell line, including the wild type, expressed alpha and mu class isozymes to the same degree and had similar but negligible expression of the mdr 1 gene. Sensitivity to various anticancer drugs and radiation was estimated by a series of cytotoxicity assays. The data confirmed that GST-pi provided a degree of protection against the toxicity of ethacrynic acid and adriamycin, but sensitivity to alkylating agents such as chlorambucil, melphalan, and cis-platinum was not influenced by GST-pi. Similarly, the response to ionizing radiation was similar for each line. Since the levels of intracellular GSH were also not significantly different, the availability of co-substrate was not a factor in determining response. In creating the GST-pi transfectants, these data establish that while increased isozyme levels can play a role in determining sensitivity to some agents, the protective effect is selective.

Actins↗

PubMed1990

Characterization of an etoposide-resistant human small-cell lung cancer cell line.

We established an etoposide (VP-16)-resistant human small-cell lung cancer cell line (H69/VP) by stepwise exposure to VP-16. The resistance of H69/VP to VP-16 was 9.4-fold that of the parent cell line (H69/P). H69/VP showed cross-resistance to Adriamycin (ADM), (4S)-4,11-diethyl-4-hydroxy-9-[(4-piperidinopiperidino) carbonyloxy]-1H-pyrano[3',4':6,7]indolizino [1,2-b]quinoline-3,14(4H,12H)-dionehydrochloride trihydrate (CPT-11), teniposide (VM-26), vindesine (VDS) and vincristine (VCR). The amount of DNA topoisomerase II (topo.II) was nearly the same in H69/P and H69/VP cells. The catalytic activity of topo.II in H69/VP cells was lower than that in the H69/P line. Accumulation of [3H]-VP-16 in H69/VP was 6.1-7.5 times lower than that in H69/P. According to Northern blot analysis, the mdr-1 mRNA level in H69/VP was markedly higher than that in H69/P. These findings suggest that H69/VP has a typical multidrug resistance (MDR) phenotype and that alteration of the drug accumulation mediated by P-glycoprotein may play an important role in resistance to VP-16. Reduced topo.II activity may also be associated with VP-16 resistance.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed1990

Phase II study of (glycolate-O,O') diammineplatinum(II), a novel platinum complex, in the treatment of non-small-cell lung cancer.

A total of 68 patients with non-small-cell lung cancer who either had not previously been treated (38) or had undergone prior therapy (30) were treated in a phase II study of (glycolate-O,O') diammineplatinum(II) (NSC 375 101D; 254-S), a new platinum complex. The drug was given as a single intravenous infusion at a dose of 100 mg/m2 every 4 weeks. All 68 patients could be evaluated for response and 62, for toxicity. Objective responses were seen in 10 of 68 cases (14.7%; 95% confidence interval, 7.3%-25.4%), and the median duration of response was 15 weeks (range, 8-23 weeks). The response rates were similar for previously untreated and treated patients (13% and 17%, respectively), including three previously treated with cisplatin. Myelosuppression was the dose-limiting toxicity. Thrombocytopenia (less than 100,000 platelets/mm3) and leukocytopenia (less than 3,000 WBC/mm3) were observed in 22 (35%) and 18 (29%) patients, respectively. Mild to moderate nausea and vomiting occurred in 45 cases (73%). No significant renal or neurotoxicity was observed. We conclude that as a single agent, 254-S is well tolerated but appears to have marginal activity against non-small-cell lung cancer.

Adenocarcinoma↗

PubMed1990

Cross-resistance to tumour promoters in human cancer cell lines resistant to adriamycin or cisplatin.

The growth inhibitory effect of tumour promoters on human leukaemia and lung cancer cell lines was examined using the [3-(4,5 dimethylthiazol)-2, 5-diphenyl-tetrazolium bromide (MTT) assay. The four cell lines used were the K562 human leukaemia cell line, its adriamycin (ADM)-resistant subline (K562/ADM), which shows the mdr phenotype, PC-9 (a human lung adenocarcinoma cell line) and its cisplatin (CDDP)-resistant subline (PC-9/CDDP), which does not show the mdr phenotype. Phorbol 12-tetradecanoate-13-acetate (TPA) and the TPA-type tumour promoters, aplysiatoxin and debromoaplysiatoxin, inhibited the growth of the two parental cell lines, K562 and PC-9. The non-TPA-type tumour promoter, okadaic acid, also inhibited the growth of the two parental cell lines in a dose-dependent manner. TPA-type and okadaic acid inhibited the growth of K562/ADM more weakly than that of K562, and showed no growth inhibition in PC-9/CDDP. Anhydrodebromoaplysiatoxin, an inactive derivative of the TPA-type tumour promoter, could suppress the growth of K562 and K562/ADM only at high concentration (more than 50 pM) and it showed similar growth inhibitory effects on the two cell lines. Okadaic acid tetramethyl ether, the inactive form of the non-TPA-type tumour promoter did not inhibit the growth of any of the cell lines. The growth inhibitory effect of these compounds was well correlated with their tumour-promoting activity. A study of the accumulation of okadaic acid revealed that the amount of 3H-okadaic acid in K562/ADM and PC-9/CDDP was similar to that in their parental cells indicating that cross-resistance to this tumour promoter in the drug-resistant cell lines is not due to a difference in the amount of drug accumulated in sensitive and resistant cells. These results suggest the presence of another common mechanism for resistance to ADM and CDDP as well as to TPA- or non-TPA-type tumour promoters.

Cell Division↗

PubMed1990

Primary lung cancer in an 18-year-old boy: case report.

An autopsy case of an 18-year-old boy with adenocarcinoma of the lung is reported. He experienced dyspnea and hemosputum in July 1988. Chest radiographs showed a diffuse bilateral streaky shadow, bilateral pleural effusion and cardiac enlargement. The diagnosis of adenocarcinoma was made by transbronchial biopsy at another hospital. He visited the National Cancer Center Hospital on October 7, 1988. The diagnosis of lung cancer was strongly suggested by positive immunohistochemical staining for pulmonary surfactant apoprotein in biopsy specimens from supraclavicular lymph nodes. Intensive systemic survey demonstrated no other primary site than the lung. The patient was treated with cisplatin, adriamycin and etoposide and his subjective symptoms such as cough and dyspnea significantly improved over the next three months. Tumor shadows in the lung increased steadily, however after February, 1989. A significant lymphangitic spread of the carcinoma and marked obsteoblastic bone metastases were revealed at autopsy.

Adenocarcinoma↗

PubMed1990

Determinants of drug response in a cisplatin-resistant human lung cancer cell line.

To elucidate the mechanism(s) of cisplatin resistance, we have characterized a human non-small cell lung cancer cell line (PC-9/CDDP) selected from the wild type (PC-9) for acquired resistance to cisplatin. PC-9/CDDP demonstrated 28-fold resistance to cisplatin, with cross resistance to other chemotherapeutic drugs including chlorambucil (X 6.3), melphalan (X 3.7) and 3-[(4-amino-2-methyl-5-pyrimidinyl)]methyl-1-(2-chloroethyl)-1-nitros our ea (ACNU) (x 3.9). There was no expression of mdr-1 mRNA in either wild-type or resistant cells. The mRNA and protein levels of glutathione S-transferase (GST) pi were similar in the two lines. A GST-mu isozyme was present in equal amounts and the activities of selenium-dependent and independent glutathione peroxidase and glutathione reductase were unchanged. The mRNA level of human metallothionein IIA and the total intracellular metallothionein levels were reduced in the resistant cells. Significantly increased intracellular glutathione (GSH) levels were found in the resistant cells (20.0 vs 63.5 nmol/mg protein) and manipulation of these levels with buthionine sulfoximine produced a partial sensitization to either cisplatin or chlorambucil. Increased GSH probably also played a role in determining cadmium chloride resistance of the PC-9/CDDP, even though this cell line had a reduced metallothionein level. Also contributing to the cisplatin resistance phenotype was a reduced intracellular level of platinum in the PC-9/CDDP. Thus, at least two distinct mechanisms have been selected in the resistant cells which confer the phenotype and allow degrees of cross resistance to other electrophilic drugs.

Adenocarcinoma↗

PubMed1990

Detection of proteins that recognize platinum-modified DNA using gel mobility shift assay.

Using a gel mobility shift assay, we have identified proteins, in the nuclear extracts of a human lung cancer cell line, that recognize cis-diamminedichloroplatinum(II) (cis-DDP, CDDP)-modified DNA. A 158-base-pair double-stranded DNA fragment, derived from pBR322 plasmid DNA, was modified by either CDDP, tetrachloro(dl-trans)-1,2-diaminocyclohexaneplatinum(IV) (tetraplatin) or trans-DDP (the stereoisomer of CDDP and clinically ineffective). These platinum drug-modified probes were incubated with nuclear extracts and analyzed by gel mobility shift assay. Proteins in the extracts selectively recognized the clinically active platinum-modified DNA fragment. No binding to the trans-DDP-modified DNA fragment was observed. These proteins may play a role in the cytotoxicity or in a DNA repair process.

Cisplatin↗

PubMed1990

Lack of correlation between interferon levels induced by polyribonucleotides and their antimetastatic effect.

The inhibitory effect of poly(A)poly(U) on the pulmonary metastasis of B16-F10 melanoma was examined in comparison with that of poly(I,C)-L,C and poly(I)poly(C). The correlation between interferon (IFN) level and antimetastatic effect was also investigated. Intraperitoneal injection of poly(A)poly(U) (50 mg/kg) into C57BL/6 mice 24 h before intravenous inoculation of B16-F10 melanoma (1 X 10(5] caused a significant decrease (p less than 0.01) in the number of pulmonary nodules 14 days after tumor challenge. But poly(I,C)-L,C (1 or 0.2 mg/kg) and poly(I)poly(C) (5 mg/kg or 1 mg/kg) did not. From the kinetic study of IFN levels induced by polyribonucleotides, poly(I,C)-L,C showed the most potent IFN-inducing activity, followed by poly(I)poly(C) and poly(A)poly(U), in this order. Plasma IFN reached a peak at 6 h and still continued to be detected at 24 h after intraperitoneal injection of the polyribonucleotides. Against B16-F10 melanoma, the cytotoxicity of spleen cells stimulated by poly(A)poly(U) (50 mg/kg) was significantly (p less than 0.05) higher than that of spleen cells stimulated by poly(I)poly(C) (5 mg/kg) both at 12 and 24 h after intraperitoneal injection of those agents. The above results that there is no correlation between the IFN levels induced by polyribonucleotides and their antimetastatic effect. More extensive study of poly(A)poly(U) might give more fruitful results, which will give valuable information for future clinical trials of this lowly toxic promising agent.

Animals↗

PubMed1990

[Efficacy of chest CT on the staging and re-staging in patients with small cell lung cancer].

Chest CT revealed to be effective to improve the quality of the staging of lung cancer concerning with the evaluation of intrathoracic lesion. The numbers of patients who had thoracic lesion as the first relapse site were higher in the group which were re-staged without the information of chest CT. The extramural review of the multi-center trial showed the inter-center bias to evaluate CR in spite of using the same X-ray imaging modalities.

Carcinoma, Small Cell↗

PubMed1990

Large cell carcinoma of the lung secreting human chorionic gonadotropin which responded to combination chemotherapy: case report.

A 68-year-old man was admitted to the National Cancer Center Hospital on November 10, 1988 to undergo chemotherapy for recurrent lung cancer, which had been resected on June 22, 1988. The tumor was diagnosed histologically as large cell carcinoma with trophoblastic differentiation, and human chorionic gonadotropin (HCG) was immunohistochemically found in tumor cells. Chemotherapy was initiated on November 14, 1988. The patient received three courses of methotrexate, actinomycin D and cyclophosphamide (MAC); and two courses of cisplatin and etoposide (PVP). Following this therapy, partial response was achieved, however, the tumor soon progressed and the serum HCG level increased to 7,571 mIU/ml. The patient was consequently given four courses of cisplatin, adriamycin, cyclophosphamide and etoposide (PACE) up to September 13, 1989, and received 52 Gy irradiation to the chest from July 20 to August 24. The tumor regressed markedly and the serum HCG decreased to within normal limits. The changes in serum HCG levels in serial samples correlated well with the clinical tumor burden. The patient is now in partial remission having survived for more than 15 months after the initiation of chemotherapy.

Aged↗

PubMed1990

[Clinical trial of KRN 8601 in patients with neutropenia induced by chemotherapy for lung cancer].

The clinical trial of KRN 8601 was conducted in patients with neutropenia induced by chemotherapy for lung cancer. Thirty-six patients were treated with KRN 8601 subcutaneously for 14 days once daily at the dose of 50 or 100 micrograms/m2, and the effects were compared with the control phase without KRN 8601 treatment. Both the elevation of neutrophil count and shortened period of neutropenia were observed by the administration of KRN 8601. The efficacy rate was 75% (18/24) at 50 micrograms/m2 and 100% (10/10) at 100 micrograms/m2. A side effect observed was fever in one patients, and in 2 patients, abnormal GOT, GPT and LDH elevation were observed in each. We concluded that KRN 8601 was clinically effective and safe at the dose of 50 micrograms/m2 or 100 micrograms/m2 for neutropenia induced by chemotherapy for lung cancer.

Adult↗

PubMed1990

Can cytotoxic activity of anthracyclines be related to DNA damage?

Accumulation, cytotoxicity, and DNA damages produced by doxorubicin (DOX), pirarubicin (THP-DOX), fluoro-doxorubicin (ME2303) or its isolated metabolite M1 have been investigated in human myelogenous leukemia cells, sensitive (K562) and resistant to DOX (K562/DOX). These compounds differed by lipophilicity and/or sugar moiety either with (DOX, THP-DOX) or without (ME2303, M1) amino group. In K562 cells, the cytotoxicity was correlated to DNA single-stranded breaks and the intracellular drug amount of DOX or M1. This was not true when the cells were treated with THP-DOX or ME2303. In addition, THP-DOX produced total DNA protein cross-linking. In K562 cells DNA damage was not repaired, while in K562/DOX repair of DNA damage produced by all drugs could be observed. Although in K562/DOX cells drug accumulation was much reduced, higher intracellular drug concentration was required to induce similar level of cytotoxicity and DNA damage. Thus, cytotoxicity produced by anthracycline is not always associated with DNA damage. Different level of resistance to DOX, THP-DOX, ME2303 or M1 is associated with reduced drug accumulation which varies with the structure.

Antibiotics, Antineoplastic↗