Phase I study with a new oral purine antagonist, SM-108, was conducted in a total of 73 cases in a 5-day consecutive schedule with the dosage ranging from 20-2,500 mg/m2 at II institutes. The incidences of subjective and objective side effects were 20.5% (15/73) and 31.5% (23/73), respectively, however the correlation between these effects and their dosages was unclear. MTD and DLF values were not determined. SM-108 levels in serum reached maximum in 2-4 hours after oral administration of SM-108, and exhibited a dose-response relationship up to the dosage of 2,000 mg/m2/day. Forty to 60% of the administered drug was excreted into urine in 24 hrs; thus, the main excretory pathway was considered to be renal. An early phase II study was undertaken in patients with lung cancer in 5 cancer centers and university hospitals. Each patient had received 400 mg/m2/day (in two divided doses) or 600 mg/m2/day (in three divided doses) for more than 2 weeks. Only one case (adenocarcinoma) showed a minor response out of 27 cases but not reached partial response according to our criteria. In the 400 mg/m2/day group and the 600 m/m2/day group the incidences of subjective side effects (mainly GI tract disturbance) were 33.3% (4/12) and 40.0% (6/15), while objective side effects (hematological changes) were 16.7% (2/12) and 26.7% (4/15) respectively. In conclusion, we could not determine the dose limiting factor and maximum tolerated dose from our phase I clinical study and early phase II study for lung cancer.

The authors studied the effect of antibiotics, hydrocortisone and anti-cancer drugs on gastrointestinal infections and dissemination by C. albicans in mice inoculated orally with C. albicans. The mice were given orally, vancomycin, amikacin and polymyxin B, and they also were injected with ampicillin and gentamicin. Hydrocortisone, cyclophosphamide (CPA) which causes leukopenia and neutropenia, and methotrexate (MTX) which injures the mucous membrane of the gastrointestinal tract were injected to the mice. In the mice treated with antibiotics and anti-cancer drugs, and inoculated orally with C. albicans, the colony forming units of the feces conspicuously increased. Gastrointestinal candidiasis was frequently observed, particularly at the cardia and the cardio-antrum line of the stomach of these mice. In addition to these sites, gastrointestinal candidiasis was observed at the antrum and the small intestine of the mice injected with MTX. C. albicans was frequently recovered from the livers and lungs of the mice treated with antibiotics and MTX + CPA which cause leukopenia, neutropenia and the damage of mucous membrane of the gastrointestinal tract. It is suggested that the threshold gut population of C. albicans is a determinant for gastrointestinal candidiasis, and that leukopenia, neutropenia and the damage of mucous membrane of the gastrointestinal tract are important factors for dissemination by C. albicans from the primary gastrointestinal lesions.

Several in vitro chemosensitivity tests have been developed to select effective anticancer agents for individual cases. However, none of them is used routinely because of the low evaluability or the time consuming nature. We developed a new practical method which is simple, rapid, and applicable to fresh human tumors. The principle of the method is to measure the ATP content of cancer cells by bioluminescence after drug exposure. A linear relationship was observed between either the number of cells or their viability and light intensity. Four established human stomach cancer cell lines and five colon cancer cell lines were examined for their chemosensitivity with a test plate having 96 wells. A clear dose-dependent response was seen with almost all drugs tested in this study, and each cell line showed an identical response to drugs. For the clinical application, cancer cells taken from three human solid tumors were tested. In all cases, the chemosensitivity was clearly evaluable. This simple, rapid and sensitive method can be a good indicator for the determination of anticancer agents in cancer chemotherapy.

Osteosarcoma tissue was transplanted into the subcutis of nude mice, and an anticancer drug was injected into the abdomen of the mice. The effects of Cis-platinum, SF-1739HP, Melphalan, Peleomycin and Aclacinomycin were tested. Only Cis-platinum had previously been used in the treatment of osteosarcoma. As the conventional method of evaluation, tumor weight change was recorded along the time course. As a new evaluation method, toluidine-blue was added into the tumor cell suspension prepared from the tumor tissue in the back of nude mice. By the intensity of staining, the tumor cells in suspension were classified into 3 categories; strongly-positive, weakly-positive and negative. Results of evaluation by the staining method were similar to those by measurement of tumor weight. Cis-platinum proved to be most effective, followed in decreasing order by SF-1739HP, Melphalan, Pepleomycin and Aclacinomycin. In conclusion, the staining method is simple and useful for screening the anti-cancer effects of drugs.

In vitro chemosensitivity of urological cancers was assessed by a human tumor colony forming assay (HTCA) and a 3H-thymidine incorporation assay. Primary tumor cells from 160 of 253 (63%) urological cancers showed adequate colony growth (greater than 30 colonies per well), and there was a 57% true positive and 100% true negative rate for predicting clinical response of anticancer agents. On the other hand, cells from 37 of 45 (82%) urologic cancers incorporated a sufficient amount of 3H-thymidine (greater than 300 cpm). However, when the positive control drug (chromomycin A3 100 micrograms/ml) was used for the assay quality control, the successful assay rate of the HTCA (38%) was lower than that of the 3H-thymidine incorporation assay (75%), while there was a significant correlation in drug sensitivities between the two assays. Thus, the 3H-thymidine incorporation assay seemed to be more useful than the HTCA for evaluating the chemosensitivity of urologic cancers.

In vitro sensitivity tests of 6 antineoplastic agents (mitomycin C, bleomycin, adriamycin, Vinblastine , cis-dichlorodiamine platinum, ACNU) were carried out on cultured cell line (OUR-10) established from human renal cell carcinoma and the results were compared with clinical results of 16 cases of renal cell carcinoma treated in our clinic. The effect of these drugs was estimated from the cell growth curve and DNA histogram determined by flow cytometry. All these drugs showed a concentration dependent effect. However, the usefulness of these drugs was not recognized in 10 clinical cases of advanced tumors.

Chemosensitivity tests to anticancer agents using human tumor clonogenic assay (HTCA), novel dye exclusion method (NDE assay), sub-renal capsule assay (SRCA), and chick embryo method (CE method) were utilized to measure the sensitivity of urological malignancies. Surgical tumor specimens from 67 patients with urological malignancies were subjected to HTCA developed by Hamburger and Salmon. An appreciable growth of colonies was obtained in 20 out of 33 renal cancers, 20 out of 30 urothelial cancers and 1 out of 4 testicular tumors examined and colonial growth adequate for chemosensitivity was obtained in 30 of the 67 patients. More than 70% decrease in the plating efficiency after anticancer drug exposure according to Von Hoff's definition, or more than 1.0 value of the "in vivo -in vitro therapeutic index" in terms of the ratio of IC90 to the peak plasma concentration of the drug tested was defined as susceptible. According to Von Hoff's definition, susceptibility to vinblastine (VBL) and cis-dichlorodiammine platinum (CDDP), was seen in 4 out of 11 patients with renal cancer, in 4 out of 15 patients with urothelial cancer and 1 out of 4 patients with renal cancer, respectively. With adriamycin (ADM) it was seen in 3 out of the 15 patients with urothelial cancer, 2 out of 10 patients with renal cancer and 1 patient with testicular tumor. According to TI, susceptibility to VBL was seen in 3 out of 7 patients with renal cancer, and with CDDP it was seen in 2 out of 12 patients with urothelial cancer, and 1 out of 2 patients with renal cancer.(ABSTRACT TRUNCATED AT 250 WORDS)

SM-5887, a new totally synthetic anthracycline derivative was evaluated the antitumor activity by subrenal capsule assay (SRCA) and the activity was compared to that of doxorubicin. The method of SRCA was the same originally developed by Bogden et al and 200 mg/kg of bredinin was administered subcutaneously 3 times every 2 days in order to induce immunosuppression of mice. Mice were given a single intravenous dose of either 30 mg/kg of SM-5887 or 15 mg/kg of doxorubicin. Fourty-four cases out of 64 were evaluable in this assay. The mean tumor growth inhibition rate (TGIR) in either SM-5887 or doxorubicin group was similar and the TGIRs of these two groups correlated well (y = 10.4 + 0.67x, p less than 0.01). Using more than 50% decrease of TGIR to define "sensitive", the chemosensitivity rates of SM-5887 and doxorubicin were 23% (10/44) and 25% (11/44) respectively. SM-5887 was effective to sarcomas and ovarian cancer especially. These results suggest that SM-5887 might have a similar antitumor activity compared to doxorubicin in clinical use.

In order to estimate tumor chemosensitivity of fluoropyrimidine derivative, inhibition of thymidylate synthetase (TS) was investigated using a nude mouse experimental system. Four human tumors xenografted in nude mice; H-111, SH-8 and SH-10, each established from gastric cancer, and EH-1 from esophageal cancer, were used. When the transplanted tumor volumes reached to approximately 200 mm3, 1-hexylcarbamoyl-5-fluorouracil (HCFU) was given for 5 days. Tumors was removed for the measurement of total and free TS at 0 hr, 6 hrs and 24 hrs after the last administrations. Simultaneously, the anti-proliferative effects were investigated according to the therapeutic protocol of NCI. No positive correlation between the inhibition rate of TS and the anti-proliferative effects was observed, although the absolute values of free TS were similar to the tumor inhibition rates. The measurement of total TS provided a highest concentration in SH-8, while extremely low in EH-1. On the analysis of free TS, a significant increase of the concentration was observed at 24 hrs after the last administration compared with at 6 hrs in SH-8. These results indicate that free TS had a potentiality as a new parameter for predicting tumor chemosensitivity of fluoropyrimidine derivative and the analysis of TS should be affected strongly by the characteristics of enzymic activity of examined tumor.

After administration of N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN) to 6-week-old, female F344 rats, various anticancer agents and immunotherapeutic agents were injected into the bladder and their effects were investigated. Injection of adriamycin and mitomycin C (MMC) into the bladder a total of 12 times, 4 weeks after administration of BBN markedly promoted carcinogenesis of the bladder. Injection of bleomycin, cis-dichlorodiamine platinum (CDDP) and picibanil into the bladder a total of 12 times, 4 weeks after administration of BBN did not promote carcinogenesis and CDDP exhibited a tendency to inhibit carcinogenesis. Injection of MMC, CA (cytarabine) and MMC + CA into the bladder a total of 12 times, 4 weeks after administration of BBN indicated that CA has the potential to inhibit the bladder carcinogenesis-promoting effect of MMC. Injection of CDDP and MMC into the bladder a total of 12 times, 20 weeks after administration of BBN inhibited proliferation of bladder carcinoma. Additionally, administration each of CDDP and MMC alone exhibited a carcinogenic effect on the bladder. The above-described results show that considerable care should be taken and that long-term observation of course is required with the use of anticancer agents such as ADM and MMC.

Prostate cancer: Considering the stagnation in chemotherapy of prostate cancer in recent years, the following experiments were carried out to determine their clinical value. Surgical specimens from 6 patients, 2 permanent cell lines (EB 33 and PC 93) originated from human prostate cancer and a tumor line serially transplanted in nude mice (PC-NCC) were subjected to chemosensitivity tests such as human tumor cloning assay (HTCA) and/or in vivo tumor growth curve experiments using nude mice. The possible chemosensitive drugs screened by using surgical specimens and PC-NCC tumor were cisplatinum (CDDP), bleomycin (BLM), 5-FU, vincristine (VCR), adriamycin (ADM) and methotrexate (MTX). Most of these drugs were also judged as "effective" by HTCA using a permanent cell line. The minimal discrepancy among them may lead to the conclusion that an in vitro assay using a cell line can substitute for the assay using surgical specimens which can not be obtained frequently. Partly based on the data obtained a chemotherapy regimen, VPM-CisCF, consisting of VCR, peplomycin, MTX, CDDP, cytosine arabinoside (Ara-C) and 5-FU, was designed. The effectiveness of this regimen was demonstrated experimentally. Testis cancer: Two different lines of experiments were performed. A human testicular cancer serially transplanted in nude mice was repeatedly exposed to CDDP in vivo to obtain hyposensitivity to this drug. The synergistic effect of CDDP and VP-16 was demonstrated in the tumor thus obtained. One of its mechanisms has been suggested by partial accumulation of cancer cells in the G1-S and G2-M phase in which CDDP exerts its potential effect.(ABSTRACT TRUNCATED AT 250 WORDS)

In case of chemotherapy against brain tumors, it is most important to choose suitable drugs for brain tumors, since human tumors have different drug sensitivity and growth. Heretofore, human tumor clonogenic assays or human glioma-bearing nude mice models were usually used for predicting the drug sensitivity of brain tumor. Human tumor clonogenic assays are one of the best in vitro tests for anticancer drug activity. However, plating efficiency is low, sometimes preventing evaluation of drug sensitivity, and the slow growth of colonies means that culture time is long. Assays using immunodeficient mice are used for predicting the drug sensitivity of human tumors; usually results reflect the sensitivity of the parent tumor. However, procedure using athymic nude mice are slow and expensive. We took notice of Murphy's system for the chemosensitivity test, in which a human tumor is transplanted into the chorioallantoic membrane (CAM) of a chick embryo, because in this system, various kinds of human tumors could be grafted in high rate. By modifying the conventional Murphy's system, we studied the efficiency of this system in predicting the drug sensitivity of brain tumors. We compared the result of a drug sensitivity test using CAM of a chick embryo with that using nude mice. First, we studied the effect of chemotherapeutic agents such as ACNU, bleomycin. Next, we studied the effect of combination treatment of CAP or CAPF. The tumor reduction rate of the sensitivity test using a chick embryo tended to agree with that using nude mice.(ABSTRACT TRUNCATED AT 250 WORDS)

The patients with cartinomatous peritonitis were treated with the intraperitoneal administration (ip) of N4-behenoyl-1-beta-D-arabinofuranosylcytosineine (BH-AC: analogue of Ara-C), and the pharmacokinetics of BH-AC ip was studied. The following results were obtained (1) Immediately after ip administration, the concentration of BH-AC in ascites became as high as 10(6) ng/ml. At 24 hours following BH-AC ip, 10(4) ng/ml of BH-AC was detected in ascites. (2) Immediately after ip administration the concentration of Ara-C derived from BH-AC in ascites became as high as 10(3) ng/ml. At 24 hours, more than 10 ng/ml of Ara-C was detected in the ascites. (3) Ara-U in ascites was detected also soon after BH-AC ip was performed. Accordingly, it is expected that deaminase may be present in ascites. (4) As compared with in ascites, Ara-C in plasma showed very low level (less than 1 ng/ml). These findings indicate that BH-AC is suitable drug for intraperitoneal administration, because BH-AC revealed low peritoneal and high plasma clearances.

In this article, we describe plausible mechanisms for drug-resistance of tumor cells to anticancer agents and also cellular modification associated with drug-resistance including heterogenous population of tumor cells, altered response to growth factor, and tumorigenicity of drug-resistant.

Two monoclonal antibodies, MRK16 and MRK20 that recognize P-glycoprotein and P-85 kd protein on the surface of adriamycin (ADM) resistant cells, respectively, were tested for the reactivity with 40 cultured leukemia/lymphoma cell lines. F(ab')2 form is essential to avoid false reaction through Fc gamma-R. Drug sensitivity of 19 representative cell lines were also examined in vitro. From this study, it was found that these cell lines were classified into 4 groups. Group 1 (4 cell lines) was insensitive to ADM, mitoxantron (MXT), etoposide (VP-16) and vincristine (VCR), and reactive to MRK16 and MRL20. Group II (1 cell line) was insensitive to the 4 drugs, but not reactive to both antibodies. Group III (3 cell lines) was insensitive to ADM, MXT and VP-16, but sensitive to VCR, and reactive to MRK20, but not to MRK16. Group IV (all other cell lines) was sensitive to these drugs, and not reactive to both antibodies. From these results, MRK16 detects P-glycoprotein-associated multidrug resistance (MDR), while MRK20 does P 85-kd-associated another type MDR (cross resistance to ADM, MXT and VP-16, but not to VCR). MRK20 reacted with monocytes, but MRK16 did not with any WBC type. One hundred and ninety eight clinical samples obtained from blood cancer were tested for the reactivity with MRK16. MRK16 did not react with any of 98 samples obtained before treatment, but did with 9 of 100 obtained at relapse or refractory stage after chemotherapy. The results indicate that MRK16 is useful to detect drug resistance phenotype of leukemia and lymphoma.