mitoguazone and Stomach-Neoplasms

The aim of the present study was to evaluate a new anticancer treatment for gastrointestinal cancer, using a combination of polyamine antimetabolites, an anticancer agent and a low-polyamine state. Two polyamine antimetabolites, given as either 40 mg/kg of methylglyoxal-bis-guanylhydrazone (MGBG) or ethylglyoxal-bis-guanylhydrazone (EGBG) and a normal diet (ND), or 20 mg/kg of each drug and a low polyamine diet (LPD), together with 1,000 mg/kg of alphadifluoromethylornithine (DFMO) were administered ip to nude mice for six consecutive days. Mitomycin C (MMC) at 2 mg/kg was then given ip for 3 alternate days. The combination of MGBG or EGBG with DFMO plus MMC resulted in an enhanced antitumor efficacy on LPD. However, the combination which included EGBG was much more enhanced than that which included MGBG and there was no evidence of any tumor regrowth. Weight loss was minimal or nil in the mice given the combination with EGBG, but was evident in those given the combination with MGBG. These results led to the conclusion that in mice, the combined therapy of EGBG with DFMO plus MMC and LPD is a safe and effective regimen for the treatment of gastric cancer.

Topics: Adenosylmethionine Decarboxylase; Animals; Body Weight; Cell Division; Combined Modality Therapy; Diet; DNA, Neoplasm; Drug Therapy, Combination; Eflornithine; Mice; Mice, Inbred BALB C; Mice, Nude; Mitoguazone; Mitomycin; Neoplasm Transplantation; Polyamines; Stomach Neoplasms

In an attempt to enhance the antitumor effects of hyperthermochemotherapy, methylglyoxal-bis-guanylhydrazone (MGBG) and alpha-difluoromethylornithine (DFMO) were used in combination with hyperthermochemotherapy of 1-(4-amino-2-methyl-5-pyrimidinyl)-methyl-3-(2-chloroethyl)-3-nitrosoure a (ACNU) against human gastric cancer (ST-2) xenotransplanted into nude mice. After priming with DFMO and MGBG, ACNU was given ip and subsequently, a 23 minute-hyperthermia was carried out by placing the leg with the tumor into a water bath of a temperature of 43.5 +/- 0.1 degrees C. The second hyperthermic treatment was given in the same manner after 48 hours. MGBG and DFMO were administered for 4 successive days from the previous day of the first hyperthermia. In mice treated with DFMO plus MGBG, either tumor growth or tumor tripling time was much the same as in the control, while in mice given MGBG, DFMO plus heat, there was a diminution in tumor growth. Hyperthermia together with MGBG, DFMO plus ACNU brought about remarkable antiproliferative effects on ST-2 tumor growth, compared to three regimens with MGBG, DFMO plus heat, MGBG, DFMO plus ACNU, as well as ACNU plus heat. These data suggest that a combination of MGBG with DFMO leads to a favorable thermosensitization to the antitumor efficacy of ACNU.

Topics: Animals; Antimetabolites, Antineoplastic; DNA, Neoplasm; Eflornithine; Hyperthermia, Induced; Mice; Mice, Inbred BALB C; Mice, Nude; Mitoguazone; Neoplasm Transplantation; Nimustine; Nitrosourea Compounds; Polyamines; Putrescine; Spermidine; Spermine; Stomach Neoplasms; Time Factors

Treatment of nude mice xenografted with human gastric cancer was carried out by polyamine antimetabolites combined with mitomycin C (MMC) and polyamine-free diet. Polyamine antimetabolites, alpha-difluoromethylornithine (DFMO) and ethylglyoxal-bis-guanylhydrazone (EGBG), were given ip in a daily dose of 1,000 mg/kg and 20 mg/kg, respectively, for 6 consecutive days. MMC 2.0 mg/kg was administered every other day. The polyamine-free diet was given from 4 days before start of the treatment through the end of the study. Although the tumor growth rate of the control group given polyamine-free diet was similar to that given normal diet, in the mice treated with EGBG, DFMO plus MMC, the antitumor effect in the polyamine-free diet group was superior to the normal diet group. In comparison with tumor growth suppression due to EGBG plus DFMO or MMC only, the polyamine-free diet group showed better result than the normal diet group to some extent. In mice treated with EGBG, DFMO plus MMC, tumor tissue spermine levels in the polyamine-free diet group were significantly depressed, compared to the normal diet group. Furthermore, marked suppression of DNA biosynthesis was observed in mice given EGBG, DFMO plus MMC together with the polyamine-free diet. These results suggest that combined treatments of polyamine antimetabolites and MMC revealed a marked enhancement of antitumor effects, under conditions of polyamine depletion, which may be responsible for the alteration in DNA structure.

Topics: Animals; Diet; DNA Replication; Drug Administration Schedule; Eflornithine; Humans; Mice; Mice, Inbred BALB C; Mitoguazone; Mitomycin; Mitomycins; Neoplasm Transplantation; Polyamines; Spermine; Stomach Neoplasms

The antitumor effects of two polyamine antimetabolites, alpha-difluoromethylornithine (DFMO) and methylglyoxal-bis-guanylhydrazone (MGBG), when combined with cis-diamminedichlroplatinum (CDDP) or mitomycin C (MMC), were studied using human gastric cancer cells xenotransplanted into nude mice. DFMO 1000 mg/kg and MGBG 50 mg/kg were given intraperitoneally for 6 successive days, while CDDP 3 mg/kg or MMC 2 mg/kg was given every second day. Although DFMO and MGBG plus MMC did suppress the tumor growth, the combination with CDDP led to no suppression, and rapid growth occurred after the cessation of therapy. The inhibition of tumoral DNA biosynthesis and a decline in polyamine levels, were also not observed. The polyamine antimetabolites when used with CDDP did not produce the desired antitumor efficacy, even though the platinum concentration in the tumor tissue was high. On the contrary, however, DFMO and MGBG when combined with MMC did suppress tumor growth, inhibited DNA biosynthesis, and tissue polyamine levels were low. These results suggest that though CDDP and MMC belong to a similar category of DNA attacking, bifunctional alkylating agents, the findings of these two drugs are contradictory. Here, the mechanism of action no doubt plays a contributory role.

Topics: Adenocarcinoma; Animals; Antineoplastic Combined Chemotherapy Protocols; Cisplatin; DNA; Drug Interactions; Eflornithine; Female; Humans; Mice; Mice, Inbred BALB C; Mitoguazone; Mitomycins; Neoplasm Transplantation; Polyamines; Stomach Neoplasms; Transplantation, Heterologous

Antitumor therapies using polyamine antimetabolites combined with 1-(4-amino-2-methyl-5-pyrimidyl)methyl-3(2-chloroethyl)-3-nitrosourea (ACNU) or fluorinated pyrimidines for human gastric cancer xenotransplanted into nude mice were studied to determine inhibiting post-therapeutic regrowth of the tumor after cessation of antitumor treatments with polyamine antimetabolites alone. ACNU 20 mg/kg, fluorinated pyrimidine, 5-FU 52.8 mg/kg and 5'-deoxy-5-fluorouridine (5'-DFUR) 100 mg/kg as well as polyamine antimetabolites, alpha-difluoromethylornithine (DFMO) 1000 mg/kg and methylglyoxal-bis-guanylhydrazone (MGBG) 50 mg/kg were given intraperitoneally for 5 successive days. When DFMO and MGBG were combined with ACNU, the post-therapeutic regrowth was definitely inhibited, while combined treatments with 5-FU or 5'-DFUR did not inhibit the regrowth. Post-therapeutic DNA biosynthesis was suppressed in mice given DFMO, MGBG plus ACNU. On the contrary, in mice treated with DFMO, MGBG plus 5-FU or 5'-DFUR, suppression of DNA biosynthesis was not observed. Tumor tissue spermine levels in the DFMO, MGBG plus 5-FU or 5'-DFUR group remained unchanged, compared to those in the DFMO + MGBG group. In mice given DFMO, MGBG plus ACNU, however, spermine levels were markedly depressed; and the ACNU alone depressed also the tissue spermine levels. These different results between nitrosourea and fluorinated pyrimidines may relate to mechanisms of action of these antitumor drugs.

Topics: Animals; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Body Weight; Carcinoma; Eflornithine; Floxuridine; Fluorouracil; Mice; Mice, Inbred BALB C; Mice, Nude; Mitoguazone; Neoplasm Transplantation; Nimustine; Nitrosourea Compounds; Ornithine; Stomach Neoplasms

Hyperthermic treatment using ACNU combined with a thermosensitizing drug, methylglyoxal-bis-guanylhydrazone (MGBG), was studied in human gastric cancer xenotransplanted into nude mice. In order to increase the intra-cellular MGBG content, intraperitoneal injection of alpha-difluoromethylornithine(DFMO) 1000 mg/kg was performed twice with an interval of 6 hours and 50 mg/kg of MGBG was given at the time of the second administration of DFMO. After 6 hours of MGBG administration, ACNU 20 mg/kg was given intraperitoneally and, subsequently a 23-minute hyperthermia was carried out in a water bath at 43.5 degrees C. After 48 hours a second hyperthermia was performed by the same method. Tumor weight was estimated using Battelle's Columbus Institute protocol and the inoculated tumors, which were extirpated 60 minutes after 3H-thymidine injection at a prescribed interval after cessation of hyperthermia, were assayed biochemically for the determination of DNA biosynthesis. In mice given ACNU, DFMO, MGBG plus heat, considerably superior results were obtained. Although the DFMO plus MGBG group was inferior in antitumor activity to the ACNU only or heat only group, the DFMO, MGBG plus heat group showed much the same antitumor effects, compared to the ACNU plus heat group. These data suggest that the thermosensitizing efficacy of MGBG may be applicable for clinical use.

Topics: Animals; Antineoplastic Combined Chemotherapy Protocols; DNA Replication; Eflornithine; Humans; Hyperthermia, Induced; Mice; Mice, Inbred BALB C; Mitoguazone; Neoplasm Transplantation; Nimustine; Nitrosourea Compounds; Ornithine; Stomach Neoplasms

Antitumor therapy using the polyamine antimetabolites, alpha-difluoromethylornithine (DFMO) and methylglyoxal-bis-guanylhydrazone (MGBG), combined with ACNU was studied in human gastric cancer xenotransplanted into nude mice. DFMO 1,000 mg/kg (in two divided doses) and MGBG 50 mg/kg were given i.p. for 6 successive days from the time when the xenotransplanted tumor weighed about 100 mg, and ACNU 20 mg/kg was given i.p. every other day from the same time. Antitumor efficacy was assessed by the time course of tumor weight as well as of DNA biosynthesis and polyamine levels in tumor tissue. Tumor weight was estimated using Battelle's Columbus Institute protocol and DNA biosynthesis was assayed biochemically by 3H-TdR injection at a prescribed interval after termination of therapy. Furthermore, tumoral polyamine levels were assayed by HPLC. This three-drug regimen showed a favorable antitumor effect, compared to those of the other two therapies with DFMO plus MGBG as well as ACNU only. These data suggest that this combined regimen may have a synergistic efficacy judging from the action mechanisms of these three drugs.

Topics: Animals; Antimetabolites, Antineoplastic; Antineoplastic Combined Chemotherapy Protocols; DNA Replication; Eflornithine; Humans; Mice; Mice, Nude; Mitoguazone; Neoplasm Transplantation; Nimustine; Nitrosourea Compounds; Polyamines; Stomach Neoplasms

The combined antitumor effects of the polyamine antimetabolites, alpha-difluoro methylornithine (DFMO) and methylglyoxal-bis-guanylhydrazone (MGBG), with CDDP were studied using human gastric cancer cells xenotransplanted into nude mice. DFMO (1000 mg/kg in two divided doses) and MGBG (50 mg/kg) were given IP for six consecutive days from the time when the xenotransplanted tumor weighted about 100 mg, and CDDP (3.0 mg/kg) was given IP every other day from the same time. Animals treated with DFMO plus MGBG with or without CDDP as well as with CDDP only displayed suppressed tumor growth, compared to untreated mice. In mice treated with these three drugs, however, tumor growth was rather rapid compared to those treated with CDDP only, although tumoral CDDP levels in animals given DFMO, MGBG and CDDP were higher than those given CDDP only. When DFMO, MGBG and CDDP or DFMO and MGBG were administered, tumoral spermidine and spermine levels decreased markedly. On the other hand, tumor DNA biosynthesis in the CDDP only group dropped markedly 24 hours after the termination of therapy. These results suggest that an alteration in the DNA structure caused by polyamine deficiency may prevent cross-link formation in DNA by CDDP.

Topics: Animals; Cisplatin; DNA Replication; Drug Therapy, Combination; Eflornithine; Humans; Mice; Mice, Inbred BALB C; Mice, Nude; Mitoguazone; Neoplasm Transplantation; Stomach Neoplasms

Topics: Adenocarcinoma; Adult; Aged; Carcinoma, Squamous Cell; Drug Evaluation; Esophageal Neoplasms; Female; Humans; Male; Middle Aged; Mitoguazone; Pancreatic Neoplasms; Stomach Neoplasms

A combined efficacy of the polyamine antimetabolites, alpha-difluoromethylornithine (DFMO) and methylglyoxal-bis-guanylhydrazone (MGBG) with two fluorinated pyrimidines was studied. DFMO, MGBG, 5-FU and 5'-deoxy-5-fluorouridine (5'-DFUR) were administered intraperitoneally to BALB/c nu/nu mice bearing xenotransplanted human gastric cancer for 5 consecutive days. Similar antitumor efficacies were observed in 3 groups treated with DFMO plus MGBG, DFMO, MGBG plus 5-FU as well as DFMO, MGBG plus 5'-DFUR. The two groups on 5-FU or 5'-DFUR alone did not differ in antitumor effects from the control, although reasonable levels of 5-FU were involved in tumor tissues. Hepatic and splenic 5-FU levels after 5-FU administration were significantly higher than those after 5'-DFUR, and marked decrease in mouse body weight was caused by 5-FU alone as well as 5-FU plus polyamine antimetabolites for 5 consecutive days. DNA biosynthesis and spermine levels in the tumor tissues on day 2 after cessation of the treatments dropped in 3 groups with DFMO plus MGBG, DFMO, MGBG plus 5'-DFUR as well as DFMO, MGBG plus 5-FU, while on day 6 there was little difference between the control and treated groups. These data suggest that combination with 5-FU or 5'-DFUR does not enhance the antitumor activity of polyamine antimetabolites by this experimental regimen.

Topics: Animals; DNA Replication; Drug Therapy, Combination; Eflornithine; Floxuridine; Fluorouracil; Mice; Mice, Nude; Mitoguazone; Ornithine; Polyamines; Spermine; Stomach Neoplasms

The antitumor effects of alpha-difluoromethylornithine (DFMO), methylglyoxal-bis-guanylhydrazone (MGBG) and mitomycin C (MMC), administered separately or in various combinations, on human stomach cancer cells xenotransplanted into BALB/c nude mice were studied using the protocol of Battelle's Columbus Laboratories (Ovejera et al., 1978). DFMO (1,000 mg/kg in 2 divided doses) and MGBG (50 mg/kg) were given intraperitoneally (i.p.) for 7 consecutive days from the time when the tumor weighed about 100 mg. MMC (2 mg/kg) was given i.p. every other day from the same time. Animals treated with either DFMO or MGBG alone displayed tumor growth comparable to that seen in untreated controls. In mice treated with DFMO plus MGBG with or without MMC, or in mice treated only with MMC, tumor growth was significantly lower than in untreated mice. In the group which received only combined DFMO/MGBG there was a rapid regrowth of the tumor after termination of therapy. Tumor putrescine levels decreased within 4 days following the administration of DFMO; however, spermidine levels did not decline with either DFMO or MGBG treatment even after 7 days. When combined DFMO/MGBG was given, there was a significant decline in spermidine levels 7 days after the initiation of treatment. In contrast, when MMC alone was administered, putrescine and spermidine levels in the tumor did not differ from those in control mice. Spermine decreased markedly in tumor with the combined administration of DFMO/MGBG as well as with combined DFMO/MGBG/MMC, but decreased only slightly when MMC alone or MMC plus either DFMO or MGBG was administered. By the 7th treatment day, DNA biosynthesis in the tumor had dropped markedly in all groups except those receiving DFMO or MGBG alone.

Topics: Adenocarcinoma, Papillary; Animals; Antineoplastic Combined Chemotherapy Protocols; Chromatography, High Pressure Liquid; DNA; Eflornithine; Humans; Injections, Intraperitoneal; Male; Mice; Mice, Inbred BALB C; Mice, Nude; Mitoguazone; Mitomycin; Mitomycins; Ornithine; Polyamines; Stomach Neoplasms

An attempt was made to analyse tumor growth after cessation of combined therapy with the polyamine biosynthesis inhibitors, alpha-difluoromethylornithine (DFMO) and methylglyoxal-bis-guanylhydrazone (MGBG), as well as mitomycin C (MMC). DFMO 1000 mg/kg, MGBG 50 mg/kg and/or MMC 2 mg/kg were given intraperitoneally to BALB/c nu/nu mice xenotransplanted human gastric cancer, and its growth as well as DNA biosynthesis were measured daily, after cessation of these combined treatments. Histological observation of the tumor was also performed by hematoxylin-eosin staining. The combination with DFMO and MGBG stunted tumor growth during the treatment, but 3 days later its growth and DNA biosynthesis were accelerated distinctly. MMC injection halted tumor growth, and 5 days after termination of MMC injection its growth rate and DNA biosynthesis almost completely recovered. The microscopic findings on the 4th day after termination of MMC injection were similar to those of DFMO + MGBG treatment. The combination DFMO, MGBG and MMC suppressed not only tumor growth during the treatment, but also tumor growth and DNA biosynthesis over 7 days. The histologic observation 4 days later revealed extensive damage.

Topics: Animals; DNA Replication; DNA, Neoplasm; Drug Therapy, Combination; Eflornithine; Guanidines; Humans; Mice; Mice, Nude; Mitoguazone; Mitomycin; Mitomycins; Neoplasm Transplantation; Ornithine; Stomach Neoplasms

A combined effect of the polyamine biosynthesis inhibitors, alpha-difluoromethylornithine (DFMO) and methyglyoxal-bis-guanylhydrazone (MGBG) with mitomycin C (MMC) was studied. DFMO, MGBG and MMC were given intraperitoneally to nude mice xenotransplanted human gastric cancer. This new combination of the three drugs resulted in the complete halt of the xenotransplanted tumor growth and marked decline of spermine levels in the tumor tissues. The other treatments with DFMO and MGBG as well as MMC alone were inferior to this new combined therapy in suppression in both tumor growth and tissue spermine level. These data suggest that this new combined treatment be effective against human gastric cancer.

Topics: Animals; Antineoplastic Combined Chemotherapy Protocols; Eflornithine; Humans; Mice; Mice, Nude; Mitoguazone; Mitomycin; Mitomycins; Neoplasm Transplantation; Ornithine; Stomach Neoplasms

The polyamine synthesis inhibitors--alpha-difluoromethylornithine (DFMO) and methylglyoxal bis (guanylhydrazone) (MGBG)--were put to antitumor tests based on the premise of treatment for human gastrointestinal cancer. The both drugs were administered intraperitoneally to BALB/c nude mice xenoplanted human gastric cancer for 10 consecutive days. Both marked antitumor effects and side effects were observed in mice treated at the dosage of DFMO 500 mg/kg/day and/or MGBG 50 mg/kg/day and/or MGBG 30 mg/kg/day brought about significant antitumor effects as well as less side effects. Microscopic observation revealed antitumor actions of these drugs as cytostatic rather than cytocidal. Tumor regrowth after the termination of this combined treatment, however, was noticed. Judging from these data, the both drugs may be effective against human gastrointestinal cancer with minor side effects.

Topics: Animals; Cell Division; Drug Synergism; Drug Therapy, Combination; Eflornithine; Gastrointestinal Neoplasms; Guanidines; Mice; Mitoguazone; Neoplasms, Experimental; Ornithine; Polyamines; Stomach Neoplasms