Different changes in resistance index between uterine artery and uterine radial artery during early pregnancy.

BACKGROUND: Changes in blood flow impedance of the uterine artery (UA) and uterine radial artery (RA) which is in the lower-extremity of the UA were examined during early pregnancy. METHODS: Blood flow impedance was assessed by transvaginal color-pulsed-Doppler-ultrasonography in 72 women from weeks 4-16 of pregnancy and expressed as a resistance index (RI). RESULTS: RA-RI remained at the late-luteal phase level until the 5th week of pregnancy, decreased until the 7th week, and remained low until the 10th week. UA-RI remained at the late-luteal phase level until the 10th week, and then gradually decreased until the 16th week. In nine women with spontaneous abortion, five out of six women with impaired growth of the gestational sac showed high RA-RI at the 6th week of pregnancy, whereas all three women with loss of fetal heart beat at the 8th week showed normal changes in RA-RI. CONCLUSIONS: Our results show different changes in blood flow impedance between the UA and RA during early pregnancy. A significant decrease of RA-RI after the 5th week may reflect vascular remodeling in the maternal-fetal interface at placentation, whereas a significant decrease of UA-RI after the 10th week may reflect changes of the whole uterine blood flow associated with uterine growth.

Sequence-dependent antitumor efficacy of combination chemotherapy with nedaplatin, a newly developed platinum, and paclitaxel.

We evaluated the sequence dependency of antitumor efficacy and toxicity in combination therapy of nedaplatin (NDP) with paclitaxel (TXL) against Lewis lung carcinoma. The sequential administration of NDP prior to TXL (NT therapy) resulted in severe body weight loss followed by frequent toxic death of mice. In contrast, the sequential dosing of TXL prior to NDP (TN therapy) resulted in synergistically enhanced inhibition of tumor growth with less toxicity compared with the NT therapy. Comparing the antitumor activity of NDP plus TXL with that of cisplatin (CDDP) plus TXL or carboplatin (CBDCA) plus TXL, the combination effect of NDP plus TXL was significantly higher than that of CDDP plus TXL or CBDCA plus TXL. These results indicate that the TN therapy may have significant potential in clinical use.

Processing of beta-dystroglycan by matrix metalloproteinase disrupts the link between the extracellular matrix and cell membrane via the dystroglycan complex.

The dystroglycan complex is a membrane-spanning complex composed of two subunits, alpha- and beta-dystroglycan. alpha-dystroglycan is a cell surface peripheral membrane protein which binds to the extracellular matrix (ECM), whereas beta-dystroglycan is an integral membrane protein which anchors alpha-dystroglycan to the cell membrane. The dystroglycan complex provides a tight link between the ECM and cell membrane. Dysfunction of the dystroglycan complex has commonly been implicated in the molecular pathogenesis of severe forms of hereditary neuromuscular diseases, including Duchenne muscular dystrophy, Fukuyama-type congenital muscular dystrophy and sarcoglycanopathy (LGMD2C, -D, -E and -F). To begin to clarify the pathway by which the dysfunction of the dystroglycan complex could lead to muscle cell degeneration, we investigated the proteolytic processing of the dystroglycan complex in this study. We demonstrate that (i) a 30 kDa fragment of beta-dystroglycan is expressed in peripheral nerve, kidney, lung and smooth muscle, but not skeletal muscle, cardiac muscle or brain, and (ii) this fragment is the product of proteolytic processing of the extracellular domain of beta-dystroglycan by the membrane-associated matrix metalloproteinase (MMP) activity. Importantly, furthermore, we demonstrate that this processing disintegrates the dystroglycan complex. Our results indicate that the processing of beta-dystroglycan by MMP causes the disruption of the link between the ECM and cell membrane via the dystroglycan complex, which could have profound effects on cell viability. Based on these and previously reported findings, we propose a hypothesis that this processing may play a crucial role in the molecular pathogenesis of sarcoglycanopathy.

Antitumor effect of a new selective matrix metalloproteinase inhibitor, MMI-166, on experimental pancreatic cancer.

The antitumor effect of a new matrix metalloproteinase inhibitor, MMI-166, which is a selective inhibitor of MMP-2 and -9, was examined in the hamster pancreatic cancer cell line PGHAM-1. In vitro, MMI-166 inhibited the gelatinase activity of MMP-2 and -9 derived from PGHAM-1 cells, and dose-dependently inhibited invasion of PGHAM-1 through a basement membrane-like barrier. MMI-166 showed no apparent cytotoxicity to PGHAM-1 cells in culture at 100 microgram/ml. MMI-166 (200 mg/kg) or vehicle were administered orally, once daily, from day 1 until day 21 after implantation in the orthotopic implantation model of PGHAM-1. MMI-166 significantly reduced the incidence of liver surface metastasis from 66.7% to 20.0%, and it reduced the number of liver surface metastases per animal from 6.17 to 2.00, but this reduction was not significant. MMI-166 significantly reduced the volume of pancreatic tumors from 718.3 +/- 220.0 mm(3) to 222.8 +/- 85.4 mm(3). Treatment of pancreatic tumors with MMI-166 caused a significant reduction in the microvessel density from 37.90 +/- 10.18/mm(2) to 16.16 +/- 3.15/mm(2) and a significant increase in apoptotic index from 1.75 +/- 0.41% to 3.96 +/- 0.38%, but there was no significant difference between tumor cell proliferation in the MMI-166-group and the control group. These results showed that selective MMP inhibition could limit both cancer spread and angiogenesis in pancreatic cancer. The selective MMP-2 and -9 inhibitor MMI-166 may be of therapeutic use in the treatment of pancreatic cancer because of its inhibitory effect on invasion and angiogenesis.

Preclinical in vivo antitumor efficacy of nedaplatin with gemcitabine against human lung cancer.

The antitumor efficacy of the combination of nedaplatin (NDP) with gemcitabine (GEM) was evaluated. We also compared the antitumor activity of NDP plus GEM with that of cisplatin (CDDP) plus GEM or carboplatin (CBDCA) plus GEM. Ma44, which is a human lung cancer sensitive to GEM, and NCI-H460, which is a human lung cancer refractory to GEM, were used in this study. GEM was injected i.v. once followed by i.v. injection of NDP at an interval of approximately 30 min into tumor-bearing athymic mice. GEM was administered again 3 or 4 days thereafter. Combined dosing of NDP with GEM resulted in synergistically enhanced inhibition of tumor growth in the Ma44 tumor model. NDP plus GEM was also effective against Ma44 cells when given late in the therapy, a model for advanced disease. Potent augmentation of growth inhibition by NDP with GEM was also found with the NCI-H460 tumor model. The combination effect of NDP plus GEM appeared to be superior to that of CDDP plus GEM or CBDCA plus GEM in both tumor models. Toxicity in terms of blood cell numbers was not enhanced by the combination of NDP with GEM. These results suggest the effectiveness of combination of NDP with GEM for clinical therapy.

Improved in vivo antitumor efficacy and reduced systemic toxicity of carboxymethylpullulan-peptide-doxorubicin conjugates.

The antitumor efficacy of the conjugate of doxorubicin (DXR) and carboxymethylpullulan (CMPul) with Phe-Gly spacer (CMPul-FG-DXR) was evaluated using murine tumor models and compared with that of DXR. The conjugate exhibited higher antitumor efficacy against Lewis lung carcinoma than DXR. Complete tumor regression followed by long-term tumor-free survival was frequently observed when CMPul-FG-DXR was administered i.v. three times at a dose equivalent to 10 mg / kg of DXR. The superior survival as well as anti-metastatic effect of CMPul-FG-DXR in comparison with DXR was also demonstrated with the M5076 murine reticulosarcoma model. Body weight loss in mice treated with the conjugate was less than that in the DXR-treated group, indicating lower systemic toxicity of CMPul-FG-DXR. Simply mixing CMPul with DXR did not enhance the antitumor activity of DXR, showing that the conjugation of DXR with CMPul is necessary for improved antitumor activity. However, no enhanced antitumor efficacy of the conjugates was observed against a non-solid tumor model such as P388 leukemia. In summary, improved antitumor efficacy with reduced systemic toxicity of CMPul-FG-DXR was demonstrated in the present study. CMPul-FG-DXR may be useful as a cancer chemotherapy agent against solid tumors and metastases.

Inhibition of gelatinolytic activity in tumor tissues by synthetic matrix metalloproteinase inhibitor: application of film in situ zymography.

Inhibition of gelatinolytic activity in implanted tumor tissues by oral administration of N-biphenyl sulfonyl-phenylalanine hydroxamic acid (BPHA), a selective matrix metalloproteinase (MMP) inhibitor, was demonstrated by means of film in situ zymography (FIZ). Active-MMP-2 but not pro-MMP-2 showed gelatinolytic activity in FIZ, whereas both forms of MMP-2 were found to be active in conventional zymography. A mixture of either tissue inhibitors of metalloproteinase-2 or BPHA with active-MMP-2 resulted in inhibition of gelatinolytic activity in FIZ but not in zymography. Thus, FIZ, but not zymography, could detect net MMP activity in tumor tissues. When a specimen from Ma44 human lung cancer xenograft was subjected to FIZ, gelatinolytic activity was markedly detected with precise localization in the tumor tissues. The gelatinolytic activity detected in Ma44 tumor tissues was found to be mainly derived from MMPs because the gelatin-degrading activity was inhibited by pretreatment of the tumor specimen with MMP inhibitors. Oral administration of BPHA but not (-)BPHA, an enantiomer of BPHA lacking MMP inhibitory activity, successfully inhibited the MMP activity localized in Ma44 tumor tissues in both a dose-dependent and time-dependent manner. The data presented in this report showed for the first time that oral administration of synthetic MMP inhibitor could inhibit the net activity of MMP activity in tumor tissues, suggesting the usefulness of the FIZ technique for determining the effective dose of MMP inhibitor in clinical studies.

Anti-metastatic efficacy and safety of MMI-166, a selective matrix metalloproteinase inhibitor.

The anti-metastatic efficacy and safety of a newly-developed matrix metalloproteinase (MMP) inhibitor were examined. MMI-166, a N-sulfonylamino acid derivative, inhibited the enzyme activity of MMP-2, 9, and 14 but not MMP-1, 3 or 7. Daily oral administration of MMI-166 resulted in potent inhibition of metastatic lung colonization of Lewis lung carcinoma injected via the tail vein and liver metastasis of C-1H human colon cancer implanted into the spleen at inhibition levels of 43% and 63%, respectively. Daily administration of MMI-166 also resulted in prolonged survival of mice given intraperitoneal implantation of Ma44 human lung cancer cells. The anti-metastatic activity of MMI-166 was as effective as that of other MMP inhibitors with broad inhibitory spectrum. MMI-166 did not affect in vitro tumor cell growth. Neither body weight losses nor hematotoxicity was observed during long-term treatment, indicating the safety of MMI-166 in mice. These results indicate that the selective MMP inhibitor MMI-166 has therapeutic potential as an anti-metastasis agent.

[Antiangiogenic and antitumor effect of BPHA, an orally-active matrix metalloproteinase inhibitor, in in vivo murine and human tumor model].

We examined the antiangiogenic and antitumor efficacy of a newly-developed matrix metalloproteinase (MMP) inhibitor, BPHA (N-biphenyl sulfonyl-phenylalanine hydroxiamic acid). BPHA potently inhibits MMP-2, 9 and 14 but not MMP-1, 3 or 7. In contrast, (-)BPHA, an enantiomer of BPHA, was inactive against all MMP tested. Daily oral administration of BPHA in mice resulted in potent inhibition of tumor-induced angiogenesis, primary tumor growth and liver metastasis, whereas (-)BPHA did not. These results demonstrate that selective MMP inhibition is correlated with antiangiogenic and antitumor efficacy and that the selective MMP inhibitor BPHA has therapeutic potential without hematotoxic effect or loss of body weight.

Combination chemotherapy with nedaplatin and cyclophosphamide in human ovarian cancer model.

The antitumor efficacy of the combination of nedaplatin (NDP) with cyclophosphamide (CPM) was evaluated using human ovarian cancer models. Since NDP has been found to have greater antitumor activity and lower nephrotoxicity than cisplatin (CDDP), we also compared the antitumor activity of NDP plus CPM with that of CDDP plus CPM. Increasing doses of NDP (16.5, 33 and 66 mg/kg as a total dose) and a fixed amount of CPM (174 or 348 mg/kg as a total dose) were injected three times at intervals of 7 days via the tail vein into mice implanted with RMUG-S, OC9-JCK or KF-28 human ovarian cancer. Simultaneous administration of NDP with CPM resulted in markedly enhanced inhibition of tumor growth for all cancers tested. The growth inhibition and survival effect of the combination therapy of NDP with CPM against KF-28 and OC9-JCK were as potent as those of CDDP plus CPM. Neither increased hematotoxicity nor a significant difference in maximum concentration, half time or area under the curve of platinum or CPM in plasma between the single and combined treatment was found. These results suggest that the combination of NDP with CPM may be clinically effective.

Correlation of antiangiogenic and antitumor efficacy of N-biphenyl sulfonyl-phenylalanine hydroxiamic acid (BPHA), an orally-active, selective matrix metalloproteinase inhibitor.

The antiangiogenic activity and antitumor efficacy of a newly developed matrix metalloproteinase (MMP) inhibitor were examined. N-biphenyl sulfonyl-phenylalanine hydroxiamic acid (BPHA) potently inhibits MMP-2, -9, and -14, but not MMP-1, -3, or -7. In contrast, (-)BPHA, an enantiomer of BPHA, was inactive against all MMPs tested. Daily oral administration of 200 mg/kg BPHA, but not (-)BPHA in mice resulted in potent inhibition of tumor-induced angiogenesis, primary tumor growth, and liver metastasis. The growth inhibition activity of BPHA was 48% and 45% in a B16-BL6 melanoma and F2 hemangio-endothelioma model, respectively. BPHA also showed 42% inhibition of the liver metastasis of C-1H human colon carcinoma cells. These results indicate that selective MMP inhibition is correlated with antiangiogenic and antitumor efficacy and that the selective MMP inhibitor BPHA has therapeutic potential.

Enhanced antitumor efficacy of nedaplatin with 5-fluorouracil against human squamous carcinoma xenografts.

BACKGROUND: The antitumor efficacy of a combination of Nedaplatin (NDP) with 5-fluorouracil (5-FU) was evaluated using human squamous carcinomas in vivo. Because NDP was developed as a second generation platinum complex, we also compared the antitumor activity of NDP with 5-FU with that of Cisplatin (CDDP) with 5-FU. MATERIALS AND METHODS: 5-FU was injected daily for five days and either NDP or CDDP was injected once via the tail vein of mice implanted with KB3-1, OCC-1-JCK, LJC-1-JCK and Ma44 human squamous carcinomas. In some experiments, continuous administration of 5-FU using an osmotic pump was utilized. RESULTS: The sequential administration of 5-FU prior to NDP or CDDP (FN or FC therapy) resulted in enhanced inhibition of tumor growth in comparison with NDP, CDDP or 5-FU monotherapy against KB3-1, OCC-1-JCK and LJC-1-JCK squamous carcinomas. The combination of FN treatment was synergistic and as effective as that of FC treatment. FN treatment with continuous infusion of 5-FU using an osmotic pump, also led to enhanced tumor growth inhibition and prolonged survival against Ma44 squamous carcinoma. CONCLUSION: The results demonstrated the antitumor efficacy NDP with 5-FU against four human squamous carcinoma xenografts and suggested the clinical effectiveness of FN treatment.

Antitumor efficacy of nedaplatin, a novel platinum complex, with cyclophosphamide in murine and human tumor model.

BACKGROUND: The antitumor efficacy of the combination of Nedaplatin (NDP) with cyclophosphamide (CPM) was evaluated using murine and human carcinoma implanted mice. NDP was developed as a second generation platinum complex. Because of its superior antitumor activity and lower nephrotoxicity than Cisplatin (CDDP), we also compared the antitumor activity of NDP plus CPM with that of CDDP plus CPM. MATERIALS AND METHODS: Various doses of NDP or CDDP (1/4 to 1 maximum tolerated dose; MTD) and CPM (58 or 78 mg/kg) were injected once via the tail vein into mice implanted with Lewis murine lung carcinoma or Ma44 human lung carcinoma. RESULTS: Simultaneous administration of NDP or CDDP with CPM resulted in synergistically enhanced inhibition of tumor growth and prolonged survival in comparison with therapy using only NDP, CDDP or CPM. The combination therapy of NDP with CPM showed a superior survival effect with frequent long-term tumor-free survivors in comparison to that of CDDP plus CPM without increased hematotoxicity. The augmented antitumor efficacy of the combination of NDP with CPM was also demonstrated against Ma44 human lung carcinoma. CONCLUSION: The results suggested the effectiveness of using a combination of NDP with CPM for clinical therapy.

Anticancer efficacy in vivo and in vitro, synergy with 5-fluorouracil, and safety of recombinant methioninase.

The elevated exogenous-methionine dependency of tumors for growth has been observed in all major cancer cell types. We have previously cloned a methioninase (rMETase) from Pseudomonas putida to deplete methionine. Growth inhibition followed by apoptotic cell death was induced by treatment of tumor cells with rMETase in vitro. A single i.p. injection of 300 units of rMETase can lower the serum methionine level in the mice from 70 microM to less than 1 microM within 2 h and maintain this depleted level for 8 h. Repeated dosing of rMETase of tumor-bearing mice could be administered without acute immune-hypersensitivity. rMETase treatment demonstrated growth inhibitory activity against human tumors in nude mice, including those which were multiple drug-resistant. No body weight loss or hematotoxicity, except a slight anemia, was found throughout the therapy. The combined treatment of the Lewis lung carcinoma with a fixed rMETase dose and increasing doses of 5-fluorouracil (5-FU) resulted in a dose-dependent enhanced antitumor efficacy for survival as well as tumor growth inhibition. Thus, methionine depletion by rMETase potentiates the antitumor efficacy of 5-FU. The data presented in this report thus indicate that rMETase is active alone, is synergistic in combination with 5-FU, and has negligible toxicity suggesting a novel clinical approach for effective cancer therapy.

Synergy of the combination of nedaplatin with etoposide in murine and human lung carcinoma.

BACKGROUND: The combination of cisplatin (CDDP) and etoposide (ETP) has been shown to be an effective treatment for lung cancer. Nedaplatin (NDP) has been developed as a second generation plainum complex. Because of its superior antitumor activity and lower nephrotoxicity in comparison with CDDP, the antitumor effects of NDP in combination with ETP against murine and human lung cancer was investigated. MATERIALS AND METHODS: Lewis murine lung carcinoma, RERF-LC-AI, and Ma44 human lung cancer were used in this study. NDP (1/4 to 1 maximum to related dose; MTD) and CDDP (1/4 to 1 MTD) were administered once and ETP (1/32MTD) was administered daily for five days via the tail vein of mice. RESULTS: In the mice bearing Lewis lung carcinoma, a combination of NDP and ETP resulted in synergistically enhanced inhibition of tumor growth (Treated/Control ratio; T/C = 0.001) in comparison with either NDP or ETP alone (T/C = 0.12 for NDP, T/C = 0.13 for ETP), and prolonged survival (Increased Life Span; ILS% > or = 172) in comparison with either NDP or ETP alone (ILS% = 65 for NDP, ILS% = 54 for ETP). NDP showed a more potent combination effect with ETP than CDDP did for both growth inhibition and survival. This effect was confirmed in human lung cancer. Although body weight loss was enhanced by the combined treatment, it was tolerable. With regards to myelosuppression, no significant difference between NDP plus ETP and CDDP plus ETP was observed. CONCLUSION: These results suggest the superiority of a combination of NDP with ETP against CDDP with ETP as a clinical therapy for lung cancer.

Highly selective and orally active inhibitors of type IV collagenase (MMP-9 and MMP-2): N-sulfonylamino acid derivatives.

Various N-sulfonylamino acid derivatives were synthesized and evaluated for their in vitro and in vivo activities to inhibit type IV collagenase (MMP-9 and MMP-2). When the amino acid residue and the sulfonamide moiety were modified, their inhibitory activities were greatly affected by the structure of the sulfonamide moiety. A series of aryl sulfonamide derivatives containing biaryl, tetrazole, amide, and triple bond were found to be potent and highly selective inhibitors of MMP-9 and MMP-2. In addition, these compounds were orally active in animal models of tumor growth and metastasis. These results revealed the potential of the N-sulfonylamino acid derivatives as a new type of candidate drug for the treatment of cancer.

[Augmented antitumor activity in combination chemotherapy of nedaplatin with etoposide].

Augmented antitumor activity in combination chemotherapy of Nedaplatin (NDP) or Cisplatin (CDDP) with Etoposide (ETP) against murine and human lung cancer cells was demonstrated. NDP and CDDP were administered once and ETP daily for five days via tail vein. In the mice bearing Lewis lung carcinoma, a combination of NDP and ETP resulted in synergistically enhanced inhibition of tumor growth, and prolonged survival in comparison with either NDP or ETP alone. NDP showed a more potent combination effect with ETP than CDDP did. These effects were also demonstrated in human lung cancer cell lines. Although body weight loss was enhanced by the combination of NDP or CDDP with ETP, it was tolerable, and no significant difference between NDP plus ETP and CDDP plus ETP was observed. Thrombocytopenia was not enhanced in the combined treatment of NDP with ETP. These results suggest the usefulness of the combination of NDP with ETP as a clinical therapy for lung cancer.

Sequence-dependent antitumour efficacy of combination chemotherapy of nedaplatin, a novel platinum complex, with 5-fluorouracil in an in vivo murine tumour model.

The antitumour efficacy of a sequential combination of nedaplatin (NDP) and 5-fluorouracil (5-FU) was evaluated using Lewis lung carcinoma in vivo. NDP was developed as a second generation platinum complex. Because it has greater antitumour activity and lower nephrotoxicity than cisplatin (CDDP), we also compared the antitumour activity of NDP plus 5-FU with that of CDDP plus 5-FU. A fixed 5-FU dose was injected daily for 5 days and increasing doses of either NDP or CDDP were injected once via the tail vein into the Lewis lung carcinoma-implanted mice. The sequential administration of either NDP or CDDP prior to 5-FU (NF or CF therapy) resulted in severe body weight loss followed by the death of the tumour-bearing mice when the high-dose of NDP or CDDP was administered. In contrast, the sequential administration of 5-FU prior to NDP or CDDP (FN or FC therapy) resulted in synergistically enhanced inhibition of tumour growth and prolonged survival in comparison with NDP, CDDP or 5-FU monotherapy. At the high-dose of NDP in FN therapy, a reduction of tumour size and long-term tumour-free survival were frequently observed. The survival effect of the combinations of NDP with 5-FU was superior to those of the combination of CDDP with 5-FU. In conclusion, the sequence-dependent antitumour efficacy and toxicity of the combination of NDP or CDDP with 5-FU was demonstrated in this study, and FN therapy appeared to be the most efficient regimen as a clinical therapy.

[Augmented antitumor efficacy of combination chemotherapy of nedaplatin with 5-fluorouracil in in vivo murine and human tumor model].

Augmented antitumor activity was demonstrated in combination chemotherapy of Nedaplatin (NDP) or Cisplatin (CDDP) with 5-fluorouracil (5-FU) against murine lung carcinoma and human squamous carcinoma from head and neck. Either NDP or CDDP (1/4 to 1 maximum tolerated dose; MTD) was injected once and 5-FU (1/16 MTD) was injected daily for five days via tail vein to tumor-implanted mice. The sequential administration of either NDP or CDDP prior to 5-FU (NF or CF therapy) showed severe body weight loss followed by the toxic death of tumor-bearing mice at the MTD of NDP or CDDP. In contrast, the reverse sequence of the treatment, that is, 5-FU prior to NDP or CDDP (FN or FC therapy), resulted in the synergistically enhanced inhibition of tumor growth and the prolonged survival in comparison with NDP, CDDP or 5-FU monotherapy. The antitumor activities of the combinations of CDDP with 5-FU was less than those of the combination of NDP with 5-FU. Especially, at the MTD of NDP in FN therapy, long-term tumor-free survival was frequently observed. Thus, FN therapy was thought to be the most efficient regimen in combination of NDP with 5-FU as a clinical therapy.

Combination therapy with cisplatin, 5'-deoxy-5-fluorouridine (5'-DFUR) and mitomycin (MMC) in patients with inoperable, advanced gastric cancer.

The optimal dose of cisplatin (CDDP) for combination chemotherapy for the treatment of inoperable, advanced gastric cancer has yet to be established. We therefore performed a randomized study to compare the therapeutic usefulness of two dose levels of cisplatin. 5'-deoxy-5-fluorouridine (5'-DFUR 1,400 mg/m(2)/d) was given orally on days 1 to 4 and 15 to 18. Mitomycin C (MMC, 5.75 mg/m(2)/d) was injected intravenously on day 5. In addition, 80 mg/m2/d of CDDP (regimen A) or 60 mg/m(2)/d of CDDP (regimen B) was given by 2-h intravenous drip infusion on day 5. This treatment cycle was repeated every four weeks. Fifty-six patients were enrolled. Clinical response was evaluated in 32 patients (regimen A, 16 patients; regimen B? 16 patients) with measurable lesions. The response rate was significantly higher with regimen A (9 PR/16, 56.3%) than with regimen B (3 PR/16, 18.9%) (p=0.028, chi(2) test). Median survival was slightly but not significantly longer with regimen A (7.4 months) than with regimen B (6.3 months). Drug toxicity included myelosuppression and gastrointestinal symptoms, but there were no serious adverse reactions or differences in safety between the treatment regimens. Regimen A was associated with a high response rate and low toxicity. The optimal dose of CDDP in combination with 5'-DFUR and MMC for the treatment of advanced gastric cancer is regarded to be 80 mg/m(2).