Biomedical subjects

S Tsukagoshi

Publications and source records attributed to S Tsukagoshi.

At least 55 records · Page 3Linked to original sources

PubMed1995

In vitro and in vivo antitumor activity of the interferon inducer bropirimine.

In vivo and in vitro antitumor effects of an interferon (IFN)-alpha inducer, bropirimine (2-amino-5-bromo-6-phenyl-4(3H)-pyrimidinone), were examined in the murine tumor system. The antitumor effects were studied in Meth A cells, which were the most sensitive to bropirimine in the murine cell lines tested. The direct inhibitory activity of the drug was not reduced when Meth A cells were incubated with bropirimine and anti-IFNs, indicating that the inhibition is not due to autocrine IFN induction from tumor cells. The drug partially inhibited the uptake of [3H]thymidine, [3H]uridine and [3H]leucine. Cell cycle analysis with flow cytometry showed that the drug decreased G0/G1 phase and increased G2/M phase Meth A cells. The drug administered i.p. exhibited a remarkable antitumor effect against Meth A cells which were implanted i.p. These results suggested that the drug induced the in vivo antitumor effect by its direct antitumor activity.

Animals↗

PubMed1995

Synthesis and antitumor activity of novel dolastatin 10 analogs.

Dolastatin 10 (1) is a potent antineoplastic pentapeptide. Novel dolastatin 10 analogs each modified at one of the constituent amino acid derivatives, were synthesized and their antitumor activity was evaluated against P388 leukemia in mice. The structural requirements for antitumor activity are discussed. Some of the analogs, 31c, 35c, 38b, and 50c showed excellent activity in vivo. Highly active 50c, which lacks the thiazole group of 1, was selected for further development as an antitumor agent.

Animals↗

PubMed1995

[Introduction of a new aromatase inhibitor fadrozole hydrochloride hydsate].

Fadrozole (CGS 16949 A, brand name: Afema) is an aromatase inhibitor developed firstly in Japan. This compound reduces estrogen levels in the body after administration, suppressing the growth of breast cancer. In animal experiments, this showed an inhibitory activity in vivo against estrogen-depended mammary tumor and the effect was potentiated by the combination of tamoxifen cytrate. In the domestic clinical trials against post-menopausal advanced-recurrent breast cancer, irrespective of the cases with ER positive or negative and even including pretreated cases, the compound showed response rate of 19.3%, the rate of long NC of 18.2%, and the total response rate of 37.5%. The prognosis of NC cases was similar to the effective (CR + PR) cases. The median survival time was 323.5 days which were better than the previous endocrine therapies. The side effects mainly consisted of nausea, vomiting, loss of appetite, abdominal pain, and fatigue, but these were all the level of grade 1. This compound-seemed to be a promising drug for the treatment of patients with post-menopausal breast cancer.

Animals↗

PubMed1995

[Porfimer sodium (Photofrin-II)].

Porfimer sodium (Photofrin II) is a photosensitizer which distributes selectively to tumor tissues, and causes tumor cell death by combination with light irradiation. Photodynamic therapy (PDT) by combination of porfimer sodium and laser was developed as a new cancer therapy. Tumor selectivity of porfimer sodium are based on the following reasons; 1) high affinity for lipoprotein, especially, low density lipoprotein (LDL), 2) elevation of LDL receptor activity in cancer tissue, and 3) lack or imcompleteness of lymphatic system in cancer tissue. Porfimer sodium is activated by laser irradiation at 630 nm, which can reacts with tissue oxygen to produce highly reactive excited siglet oxygen (1O2). This highly reactive molecule is subsequently capable of killing tumor cells through oxidation of cellular component like mitochondrial enzymes. In addition, this highly reactive intermediate causes destruction of the tumor capillaries, which accelerates tumor cell death. The growth suppression or lethal damage to tumor cells by PDT of porfimer sodium and excimer dye laser were observed in experimental tumor models. In human clinical trials, the rates of complete response (CR) for roentgenographically occult lung cancer, stage I lung cancer, superficial esophageal cancer, superficial gastric cancer and carcinoma in situ or dysplasia of the cervix were 84.8%, 50.0%, 90.0%, 87.5% and 94.4%, respectively. The major side effects were cutaneous symptoms e.g. photosensitivity, pigmentation, increasing GOT, GPT but these symptoms were not severe. PDT using porfimer sodium and excimer dye laser must be clinically useful for the treatment of inoperable early cancer or conservation of organ functions.

Animals↗

PubMed1995

[From the aspect of pre-clinical study of new anticancer candidate compounds].

In the pre-clinical study of anticancer candidate compounds, the following three points should be carefully evaluated before decision to enter the clinical trials. Namely, 1) the data on the antitumor efficacies (in vitro and in vivo), 2) animal toxicities and 3) pharmacological studies. Since more attention has been placed on the clinical trials to protect the right of cancer patients, the toxicity data are especially examined carefully using small and large experimental animals. Feasibility to enter in the clinical studies should be examined by above three points in the preclinical studies.

Animals↗

PubMed1995

[The clinical phase I study of TNP-351. The TNP-351 Research Committee].

The clinical phase I study of TNP-351, an antifolate drug having a novel structure, was performed through a multicenter cooperative program in 40 patients with solid tumors. The test drug was used on dosage schedules of single and daily doses for 5 or 3 days (by intravenous drip over 30 minutes, respectively). From the daily administration for 5 days, severe adverse reactions such as myelosuppression, became manifest at 5 mg/m2 (1n). This schedule was then switched to daily administration for 3 days. Administration of the test drug was initiated at a dose of 5 mg/m2. On a single-dose schedule, the dose was increased up to 100 mg/m2 (20 n), and on the 3-day daily administration schedule, up to 10.8 mg/m2 (2.2 n). Consequently, 26 of the study patients received single doses; three of them the 5-day daily administration, and 11 the 3-day daily administration. The dose-limiting factors were leukopenia and thrombopenia on both the single-dose and 3-day daily administration schedules. MTD was 100 mg/m2, and MAD, 75 mg/m2 for the single-dose schedule; and 10.8 mg/m2 and 9 mg/m2 for the 3-day daily administration schedule. WBC and platelet counts fell to nadirs at 1-2 weeks on either the single-dose or 3-day daily administration schedule, and it took the respective parameters about 1 week to recover. Subjective and objective adverse reactions to the test drug consisted of digestive tract disorders manifested as stomatitis, anorexia, nausea and vomiting; and laboratory abnormalities such as elevations of GOT and GPT in addition to the myelosuppression. Many of these adverse reactions subsided within 3 weeks after initiation of TNP-351 treatment. On the single-dose schedule, the test drug occurred chiefly in unchanged form in the blood, and in this form it disappeared from the blood biphasically with an alpha phase of 0.29-0.95 hours, and a beta phase of 7.8-14.4 hours. This disappearance pattern did not vary with an increase in dose. The 24-hour urinary excretion rate of the unchanged form amounted to 42-62% of the administered doses. On the 3-day daily administration schedule, the test drug was not accumulated in vivo. In the present study, two patients with malignant fibrous histiocytoma responded to the test drug with tumor regression. The results suggested that the recommended dosage regimen for the clinical early phase II study of the test drug should comprise a course of 9 mg/m2/day (by intravenous drip infusion over 30 minutes) every day for 3 days, which should be repeated every 3 weeks.

Adult↗

PubMed1994

Antitumor effects of IST-622, a novel synthetic derivative of chartreusin, against murine and human tumor lines following oral administration.

The antitumor effects of 6-O-(3-ethoxypropionyl)-3',4'-O-exo- benzylidenechartreusin (IST-622), a new synthetic derivative of chartreusin (CT), were investigated. Following oral administration, IST-622 showed marked antitumor effects against various mouse tumors such as P388 and L1210 leukemias, B16 melanoma, Lewis lung carcinoma, Colon 26 and Colon 38 adenocarcinomas, and M5076 reticulum-cell sarcoma. The best antitumor effects were obtained by five intermittent treatments given every 4 days. In addition, IST-622 showed a significant growth-inhibitory effect against two human tumor xenografts, a large-cell lung cancer (Lu-116) and a gastric adenocarcinoma (St-4), among the seven lines tested. IST-622, which was rapidly metabolized into 3',4'-O-exo-benzylidenechartreusin (A-132) and not into CT in vivo or in culture medium, exhibited remarkable growth-inhibitory activity against P388 leukemia in vitro, its 50% growth-inhibitory concentration (IC50) being over 20-fold lower than that of CT. IST-622 showed an in vivo antitumor effect superior to that of authentic A-132, possibly resulting from a higher absorption ratio of IST-622 through the gastrointestinal tract. IST-622 is now under clinical phase I study in Japan.

Administration, Oral↗

PubMed1994

Activation of tumor-infiltrating macrophages by a synthetic lipid A analog (ONO-4007) and its implication in antitumor effects.

ONO-4007 is a novel synthetic analog of lipid A subunit and has been shown to exert antitumor activities on various experimental tumors with less toxicity than lipopolysaccharide. It remains unclear, however, what biological activities of this compound are relevant to its antitumor effects. We therefore investigated the activation of macrophages by ONO-4007 in vitro and in vivo and its implication in antitumor effects, using mouse MM46 mammary tumor as an experimental model. Intravenous injection of ONO-4007 produced significant therapeutic effects on this solid tumor. ONO-4007 could stimulate glycogen-elicited peritoneal macrophages in vitro, not only to produce tumor necrosis factor (TNF), but also to exert cytocidal activities against MM46 cells in vitro. Substantial TNF production was induced in tumor tissue by i. v. injection of ONO-4007, and its successive administration to tumor-bearing mice gave tumor-infiltrating macrophages a prominent in vitro tumoricidal activity and primed them for in vitro TNF secretion. These results suggest that activation of tumor-infiltrating macrophages to a direct tumoricidal state as well as to TNF secretion in tumor tissues may be at least some of the antitumor effects of this novel lipid A analog.

Animals↗

PubMed1994

[A novel antitumor agent, sobuzoxane (MST-16)].

Sobuzoxane (MST-16) is an analogue of ICRF-159 which was once evaluated on the clinical efficacies in England. Zenyaku Pharm. Ind. in Japan synthesized many derivatives of bis (2,6-dioxopiperazine) and sobuzoxane was selected from the antitumor efficacies, the results of the toxicity tests and pharmacological profiles from these derivative. The compound was a new type topoisomerase II inhibitor, and G2M phase of the cell cycle was most sensitive. The clinical phase studies proved that sobuzoxane was quite effective for the treatment of malignant lymphoma (overall response rate in phase II study 29.7%) and adult T cell leukemia (response rate for acute type: 46.2%). The dose-limiting factor was leukopenia.

Animals↗

PubMed1994

[The mechanism of potentiation of the antitumor effect of 5-fluorouracil by methionine-free intravenous amino acid solution (AO-90) in rats].

AO-90, a methionine-free intravenous amino acid solution (7.43%) showed to potentiate the antitumor effect of 5-fluorouracil (5-FU) when concomitantly used as the nitrogen source in total parenteral nutrition (TPN) in Yoshida sarcoma (YS)-bearing rats. In the present experiment, this potentiation mechanism was studied by determining the serum methionine level and tumor methylenetetrahydrofolate (CH2FH4) content in YS-bearing Donryu rats given AO-90 (nitrogen 0.73g/kg on the 1st day and 1.46g/kg for the remaining 6 days) by TPN for 1 week. The rats were subcutaneously inoculated with 10(4) YS cells in the dorsum 3 days before the start of TPN. Inhibition of thymidylate synthase activity in tumor tissue after dosing of AO-90 (nitrogen 0.68g/kg on the 1st day and 1.36 g/kg for the remaining 6 days) by TPN along with daily intraperitoneal dosing of 5-FU (10 mg/kg) was also evaluated with the inoculation of 10(6) tumor cells. The results were compared with those in tumor-bearing rats given TPN with a commercially available amino acid solution containing methionine. On day 5 of TPN, the tumor-bearing rats given AO-90 showed a significantly lower serum methionine level than the control rats: 101 +/- 11 mumol/l versus 29 +/- 14 mumol/l (p < 0.01); and a higher CH2FH4 content in tumor: 7.0 +/- 2.8 pmol/g protein versus 23.7 +/- 16.6 pmol/g protein (p < 0.05). Thymidylate synthase inhibition was 81.2 +/- 5.1% in the AO-90 group and 30.9 +/- 26.3% in the control group (p < 0.01). The results of the present study suggest that AO-90 potentiate the antitumor effect of 5-FU by biochemical modulation. AO-90 concomitantly given with 5-FU for 7 days was effective not only in the allogeneic tumor model, but also in WKAH and SHR rats previously inoculated with 10(6) of syngeneic KDH-8 hepatoma cells and SST-2 adenocarcinoma cells, respectively. Weight of SST-2 adenocarcinoma in SHR rats after the TPN period was significantly smaller in the AO-90 group than in the control rats given methionine-containing TPN and 5-FU: 2.66 +/- 0.91 versus 5.12 +/- 2.11 (p < 0.05).

Amino Acids↗

PubMed1994

[Study of cardiac function in first stage examination of RA-700. RA-700 Clinical Study Group].

There are many studies in the literature on the subject of anti-neoplastic drugs for acute and chronic cardiac toxic function. It is important to check previously the cardiac toxicity of the new anti-neoplastic drugs. Now we have had a chance to study the first stage examination of RA-700, isolated from Rubia akane or Rubia cordifolia. Then we tried to study several kinds of parameters, for instance ECG, ultrasonic cardiograms and arterio-grams on cardiac toxicities of RA-700. We injected the first group of neoplastic patients only once with RA-700, while in the second group, we injected them with RA-700 for 5 consecutive days (see our previous report.) In the present study, we made some conclusions about the administration of RA-700. 1) Changes in cardiac function were noted in both groups. 2) Changes in blood pressure, sigma QRS, ejection fraction, and fractional shortening of the second group tended to be more extreme than those of the first group. Care for continuity is a concern with long-term and high doses of RA-700. 3) Because of the small sample, we could find no relationship between the changes in cardiac function and the injection doses of RA-700. 4) Therefore, the cardiac function must be checked by giving anti-neoplastic drugs to neoplastic patients.

Adult↗

PubMed1993

The effect of NC-190, a novel antitumor compound, on the cell-cycle progression of HeLa S3 cells.

A novel antitumor compound, N-beta-dimethylaminoethyl 9-carboxy-5-hydroxy-10-methoxybenzo[a]phenazine-6-carboxamide sodium salt (NC-190), has potent antitumor activity against in vivo and in vitro tumor models. In this study, we evaluated the cell-cycle effect of NC-190 on cultured HeLa S3 cells using DNA/bromodeoxyuridine(BrdU) bivariate flow-cytometric analysis. Continuous treatment with NC-190 for 72 h inhibited the growth of cultured HeLa S3 cells in a concentration-dependent manner. Its 50% growth-inhibitory concentration (IC50) was 0.039 micrograms/ml (0.085 microM). The cell-cycle effects of NC-190 were dependent on the drug concentration and the treatment period. Continuous treatment with a low concentration (0.1 micrograms/ml) of NC-190 inhibited cell-cycle progression from the G2 to the M phase, resulting in G2 accumulation. With increasing concentration, NC-190 delayed cell-cycle traverse in the S and G2 phases. At a higher (10 micrograms/ml) concentration of NC-190, cell-cycle traverse was prevented in the G1, S, and G2 phases. Under such conditions, NC-190 increased the numbers of S0-phase cells (the cells with DNA content corresponding to that of S-phase cells, but without BrdU incorporation). Treatment for 2 h with NC-190 at 10 micrograms/ml induced the accumulation of cells in the G2 phase, and cell debris was observed at 48 and 72 h after drug treatment. During this time, the proportion of cells in the S0 phase increased up to 19.2%. The colcemid-induced mitotic cell accumulation was delayed by NC-190 at a concentration of 0.1 micrograms/ml at 4 h after the addition of the drugs. The addition of higher concentrations (1 and 10 micrograms/ml) of NC-190 inhibited the increase in the mitotic fraction completely. These results indicate that the mechanism involved in the G2 arrest and the increment of S0-phase cells caused by NC-190 is associated with this compound-induced cell death.

Antineoplastic Agents↗

PubMed1993

[Recent development of new anticancer drugs in Japan].

Recent development of new anticancer drugs in Japan was reviewed. Since there are a high incidence of cancer of the digestive organs, lung cancer and breast cancer in Japan, we have been looking for novel anticancer drugs effective against these solid cancers. Currently, some of fluoropyrimidine compounds, methotrexate analogues, tubulin inhibitors from plant origins have shown their clinical activities against human non-small cell lung cancer and/or breast cancer. As the end-point on these drug development, we have put an emphasis to find drugs to contribute for the survival prolongation and improvement of quality of life of the treated patients.

Aminopterin↗

PubMed1993

[An outline of 5-HT3 receptor antagonists (1)--In pharmacological actions].

This paper described an outline of pharmacological studies of 5-HT3 receptor antagonists, mainly on ondansetron, which control nausea and vomiting associated with cancer chemotherapy. Administration of cytotoxic drugs is known to increase serotonin (5-HT) concentrations, and when released, 5-HT provokes the emetic responses via two routes; 1) 5-HT acts as an intrinsic transmitter substance and stimulates the emetic response via 5-HT3 receptors on vagal afferent terminals; 2) 5-HT transmits impulses to the vomiting center via 5-HT3 receptors on the chemoreceptor trigger zone in the area postrema of the central nervous system. 5-HT3 receptor antagonists are thought to exert an antiemetic action by specifically and competitively blocking 5-HT3 receptors.

Antiemetics↗

PubMed1993

[An outline of 5-HT3 receptor antagonists (2)--In clinical applications].

This paper described an outline of clinically applications of 5-HT3 receptor antagonists, mainly on ondansetron, which control nausea and vomiting associated with cancer chemotherapy. Clinically, 5-HT3 receptor antagonists demonstrated significantly superior antiemetic effects to metoclopramide which has been prescribed for relatively long time. The response rates for granisetron and those for ondansetron were different due to the different categorical scales. However, when the same scale was applied, similar efficacies have been observed. Introduction of the tablet form may well broaden the clinical applications. Considering the highly evaluated safety, 5-HT3 receptor antagonists, from the viewpoints of clinical usefulness and safety, seems to be useful drugs for controlling nausea and vomiting associated with cancer chemotherapy.

Antineoplastic Agents↗

PubMed1993

[A new antileukemic drug, cytarabine ocfosfate].

Cytarabine ocfosfate (commercial name: Starasid) is a prodrug having stearyl group attached to phosphoric acid at 5' position of arabinose moiety of cytosine arabinoside (Ara-C). This drug is given orally. The mode of action is in the inhibition of DNA synthesis after conversion to Ara-CTP as in Ara-C. The drug is metabolized in the liver, producing the intermediate metabolite, C-C3PCA which is converted to Ara-C gradually. This property results in the maintenance of relatively long time the blood Ara-C levels. This was proved to be active clinically against acute leukemia and MDS.

Administration, Oral↗

PubMed1993

[Development of antimetabolites, II].

Two analogues of cytosine arabinoside (ara-C) and three analogues of methotrexate (MTX) are under their clinical studies in Japan. Gemcitabine and DMDC are analogues of ara-C, showing similar antitumor efficacies each other and rather mild animal toxicities. Currently, dFdC is under phase II study, showing activity against lung cancer and DMDC under phase I study. As for MTX analogues, edatrexate, trimetrexate and TNP-351 have been put on the clinical phase studies. Among these antifolates, both edatrexate and trimetrexate have showed responses against lung cancer and we expect that TNP-351 may also show a similar response in the future. Currently, phase II studies of edatrexate and trimetrexate and phase I study of TNP-351 are under progress.

Aminopterin↗

PubMed1993

[Phase I Study of RA-700. RA-700 Clinical Study Group].

An antitumor substance, RA-700, isolated from Rubia akane or Rubia cordifolia has the novel structure. Phase I clinical study was conducted by the RA-700 clinical study group consisting of 6 institutions. A single dose administration and 5-day schedule administration were evaluated with 14 patients respectively. RA-700 was given from 0.2 to 1.4 mg/m2 in single i.v. dose study, from 0.4 to 2.0 mg/m2 in 5-day i.v. schedule study. Nausea and vomiting, fever, stomachache, mild hypotension and slight abnormality of electric-cardiogram were observed as the toxicities. In pharmacokinetic study, the elimination half-lives (t1/2) of RA-700 in plasma were 55 min, of alpha-phase and 3.9 hrs. of beta-phase by single dose study, and 23-25 min. of alpha-phase and 6-14 hrs. of beta-phase by 5-day schedule study. Accumulation was not found by 5-day schedule administration, and metabolite were not observed in plasma and urine. It seems that RA-700 is metabolized by the liver and excreted in the feces. In conclusion, the maximum tolerated dose was 1.4 mg/m2 for 5-day schedule administration.

Adenocarcinoma↗