Müllerian inhibiting substance signaling uses a bone morphogenetic protein (BMP)-like pathway mediated by ALK2 and induces SMAD6 expression

Signal reception of Müllerian inhibiting substance (MIS) in the mesenchyme around the embryonic Müllerian duct in the male is essential for regression of the duct. Deficiency of MIS or of the MIS type II receptor, MISRII, results in abnormal reproductive development in the male due to the maintenance of the duct. MIS is a member of the transforming growth factor-beta (TGFbeta) superfamily of secreted protein hormones that signal through receptor complexes of type I and type II serine/threonine kinase receptors. To investigate candidate MIS type I receptors, we examined reporter construct activation by MIS. The bone morphogenetic protein (BMP)-responsive Tlx2 and Xvent2 promoter-driven reporter constructs were stimulated by MIS but the TGFbeta/activin-induced p3TP-lux or CAGA-luc reporter constructs were not. The induction of Tlx2-luc was dependent upon the kinase activity of MISRII and was blocked by a dominant negative truncated ALK2 (tALK2) receptor but not by truncated forms of the other BMP type I receptors ALK1, ALK3, or ALK6. MIS induced activation of a Gal4DBD-Smad1 but not a Gal4DBD-Smad2 fusion protein. This activation could also be blocked by tALK2. The BMP-induced inhibitory Smad, Smad6, was up-regulated by MIS endogenously in Leydig cell-derived lines and is expressed in male but not female Müllerian duct mesenchyme. ALK6 has been shown to function as an MIS type I receptor. Investigation of the pattern of ALK2, MISRII, and ALK6 in the developing urogenital system demonstrated overlapping expression of ALK2 and MISRII in the mesenchyme surrounding the duct while ALK6 was observed only in the epithelium. Examination of ALK6 -/- male animals revealed no defect in duct regression. The reporter construct analysis, pattern of expression of the receptors, and analysis of ALK6-deficient animals suggest that ALK2 is the MIS type I receptor involved in Müllerian duct regression.

Mullerian inhibiting substance regulates NFkappaB signaling and growth of mammary epithelial cells in vivo

Müllerian inhibiting substance (MIS) inhibits breast cancer cell growth in vitro through interference with cell cycle progression and induction of apoptosis, a process associated with NFkappaB activation and up-regulation of one of its important target genes, IEX-1S (Segev, D. L., Ha, T., Tran, T. T., Kenneally, M., Harkin, P., Jung, M., MacLaughlin, D. T., Donahoe, P. K., and Maheswaran, S. (2000) J. Biol. Chem. 275, 28371-28379). Here we demonstrate that MIS activates the NFkappaB signaling cascade, induces IEX-1S mRNA, and inhibits the growth of MCF10A, an immortalized human breast epithelial cell line with characteristics of normal cells. In vivo, an inverse correlation was found to exist between various stages of mammary growth and MIS type II receptor expression. Receptor mRNA significantly diminished during puberty, when the ductal system branches and invades the adipose stroma and during the expansive growth at lactation, but it was up-regulated during involution, a time of regression and apoptosis. Peripartum variations in MIS type II receptor expression correlated with NFkappaB activation and IEX-1S mRNA expression. Administration of MIS to female mice induced NFkappaB DNA binding and IEX-1S mRNA expression in the breast. Furthermore, exposure to MIS in vivo increased apoptosis in the mouse mammary ductal epithelium. Thus, MIS may function as an endogenous hormonal regulator of NFkappaB signaling and growth in the breast.

[Efficacy of intra-arterial chemotherapy on life prolongation in patients with hepatic metastasis from colorectal cancer]

The efficacy of intra-arterial chemotherapy for life prolongation was investigated in patients with hepatic metastasis from colorectal cancer who visited our hospital from Jan. 1989-Mar. 1999, but without any other remote metastasis when the presence of their hepatic metastasis was detected. The subjects were assigned to 4 groups; group A (n = 8) was only treated by hepatectomy, group B (n = 27) by intra-arterial chemotherapy combined with hepatectomy, group C (n = 42) with intra-arterial chemotherapy alone, and group D (n = 23) by systemic chemotherapy through intra-venous or oral administration. The survival rates of these groups were determined, and the recurrence risk after hepatectomy was compared between group A and B. Further, the survival rate of the patients treated by intra-arterial chemotherapy was compared between the cases of PD and not-PD (including CR, PR, and NC). The median survival in cases of H1 and H2 was 405 days for group A, 1,018 days for group B and 245 days for group C, showing that group B had a significantly more favorable prognosis than either group A or group C. There were also significant differences in the median survival of H3 cases between group C (422 days) and group D (113 days). One-year cumulative recurrence risks in the residual livers of group A and group B were 79% and 28%, respectively. Thus, significant differences in the recurrence risk were found in the two groups. Meanwhile, the median survival of PD and non-PD cases was 240 and 588 days, respectively. These results suggested that local control by intra-arterial chemotherapy is useful for life prolongation.

[Effect of combination chemotherapy with mitomycin C and cisplatin on advanced gastric carcinoma]

A 71-year-old male with advanced gastric carcinoma with paraaortic lymph node metastases underwent distal gastrectomy. Cisplatin (CDDP) 50 mg/body was administered intravenously (i.v.) on day 1 followed by the administration of 5-fluorouracil 500 mg/body/day i.v. on day 2 through day 7. After two courses of this regimen, further enlargement of paraaortic lymph nodes was revealed by CT scan, and chemotherapy was suspended. Multiple liver and lung metastases were diagnosed 6 months after initial diagnosis, and mitomycin C (MMC) 10 mg/body i.v. was administered on day 1 followed by CDDP 50 mg/body i.v. on day 2. After three courses of this regimen, partial response of the liver metastases and complete response of the lung metastases were observed, and the general condition was markedly improved without any adverse effect except slight nausea. Though the patient died of brain metastases one year after initial diagnosis, the combination chemotherapy with MMC and CDDP was nevertheless thought to improve his quality of life.

Methionine-depletion modulates the efficacy of 5-fluorouracil in human gastric cancer in nude mice

Human tumors are generally methionine (MET)-dependent in that their growth is inhibited by MET-depletion down to levels that will still allow normal cell growth. The differential effect of methionine depletion on tumor and normal cells has suggested that methionine depletion may be able to modulate many and possibly all classes of cancer drugs. In this report, we determined if MET-depletion could modulate 5-fluorouracil (5-FU) efficacy on the human gastric cancer xenograft, SC-1-NU in nude mice. The tumor-bearing mice were treated with a MET-free diet and intraperitoneal administration of 5-FU at a dose of 30 mg/kg given for four cycles. MET depletion enhanced the antitumor activity of 5-FU by approximately two-fold with statistical significance of p < 0.05. The MET-free diet increased intratumoral thymidylate synthetase inhibition early after 5-FU administration; Therefore, MET-depletion was thought to increase the 5-FU antitumor activity by modulating intratumoral folate metabolism. The data in this report suggest the high clinical potential of methionine depletion, combined with 5-FU and leucovorin on refractory tumors such as stomach cancer.

[A case of unresectable advanced cancer of the gall bladder successfully treated by arterial infusion therapy with cisplatin]

A 70-year-old male was admitted for obstructive jaundice. He was diagnosed as an unresectable advanced cancer of the gall bladder that was stage IV associated with direct extension of the liver (Hinf3) and the bile duct (Binf3), and with enlargement of paraaortic lymph node (N4(+)) by image analyses. Intraarterial infusion therapy with cisplatin (CDDP, 50 mg) was started through the common hepatic artery. Since the primary tumor and the enlarged paraaortic lymph node shrank markedly and the bile duct was completely obstructed, additional arterial infusion with CDDP (50 mg) was made. CT examination thereafter revealed that the paraaortic lymph node enlargement disappeared although thickening of the gall bladder wall still remained. Therefore this case was considered as a complete response (CR). Then, a reservoir for hepatic arterial infusion was implanted and CDDP (a total of 230 mg) was repeatedly infused 5 times. CT scanning images taken 7 months after the start of the treatment showed neither primary tumor nor enlargement of paraaortic lymph node. An extensive cholecystectomy was performed. Histopathological examination revealed signet-ring cell carcinoma located in all layers of the gall bladder. Factors indicating clinicopathological stage were se, hinf1, vs0, bw1, hw0 and ew2 (according to the General Rules for Surgical and Pathological Studies on Cancer of Bile duct).

[A case of liver metastases from leiomyosarcoma in the chest wall which was made resectable by chemoembolization]

We here report a recently experienced case in which TAE and intra-arterial infusion chemotherapy for treatment of liver metastases of leiomyosarcoma in the chest wall caused a shrinking of the metastasized focus, thus facilitating liver resection. Patient; a 38-year-old man Present History and Courses; Resection of leiomyosarcoma in his chest wall was done in May, 1994. However, a local recurrence was noted in September, 1995, and the tumor was removed. Then, he received systemic chemotherapy with CDDP (100 mg) and ADM (45 mg). Abdominal CT and ultrasonic examinations made in February, 1996 revealed liver metastases at S2,5,8. Angiography detected densely stained images of tumors at a number of sites along with S2,5,8. Since these were thought unresectable, TAE therapy with EPIR (30 mg) and lipiodol (4 ml) was attempted 3 times. Then, a reservoir for intra-hepatic arterial infusion was implanted in April, 1996 and EPIR at a dose of 30 mg (150 mg in total) was given through arterial infusion, resulting in tumor disappearance at S5,8 but further growth of the tumor metastasizes at S2. Therefore, a resection of the left lateral segment of liver was done August 23. Though he was discharged in October, metastasis was found in the thoracic spine in December. Thus, he underwent resection of the vertebral arch including the tumor.

Antitumor activity of paclitaxel against human breast carcinoma xenografts serially transplanted into nude mice

BACKGROUND

Paclitaxel (BMS-181339: Taxol) is a promising agent against previously treated breast cancer. The antitumor activity of paclitaxel was evaluated using five human breast carcinoma xenografts in nude mice.

METHODS

Paclitaxel at 20 mg/kg dissolved in 0.2 ml ethanol/cremophor EL solution was administered intraperitoneally daily for 5 days.

RESULTS

Paclitaxel showed significant antitumor activity against MCF-7 and MX-1, but only limited activity against the other three xenografts (R-27, Br-10, and T-61), suggesting its substantially different antitumor spectrum from conventional antibreast cancer drugs. The different sensitivity of xenografts to paclitaxel was successfully reproduced in vitro using the MTT assay, when the cutoff concentration of paclitaxel was 20 microg/ml.

CONCLUSION

Since no significant differences were observed in the pharmacokinetics of paclitaxel in sensitive and resistant tumor cell lines, the efficacy of this agent seemed to depend on the sensitivity of tumor cells rather than the intratumoral concentration of agent.

Methionine starvation modulates the efficacy of cisplatin on human breast cancer in nude mice

There are few agents with activity against metastatic breast cancer. We therefore exploited the elevated methionine dependence of tumors to develop a selective and effective therapy against metastatic breast and other cancers. Methionine starvation leads to depleted methionine levels in cells, modifies methylation reactions, lowers glutathione levels and alters folate distribution and leads to a tumor-selective cell cycle arrest in late-S/G2. These effects present the opportunity for methionine depletion to modulate the efficacy of a number of different classes of chemotherapeutic drugs. This report demonstrates that methionine depletion can strongly modulate the efficacy of cisplatin against the MX-t human breast carcinoma cell line when grown in nude mice. The tumor-bearing nude mice were subjected to a methionine-free diet and were additionally treated with cisplatin i.p. at one mg/kg once a week for 3 weeks. The MX-t tumor was relatively resistant to both methionine starvation and cisplatin alone but was very sensitive to the combination of methionine starvation and cisplatin with a 32.1% T/C ratio. The intratumoral platinum concentration was higher in combination with methionine starvation than cisplatin alone, possibly accounting for at least part of the modulating effect of methionine depletion. Future studies will focus on methionine depletion via the enzyme methioninase to modulate cisplatin as well as other classes of chemotherapeutic agents in order to develop a new approach to the treatment of cancer.

[Clinical evaluation of hepatic arterial infusion chemotherapy in patients with liver metastases from colorectal cancer]

Seventy-four cases of hepatic metastasis of colorectal cancer experienced in our hospital from January 1988 to February 1996 were examined for hepatic arterial infusion chemotherapy induced macrobiotic effect. A group (21 cases of hepatectomy and hepatic arterial infusion chemotherapy), B group (31 cases of hepatic arterial infusion chemotherapy only) and C group (22 cases of iv and po systemic chemotherapy) were comparatively examined for survival rate using Kaplan-Meier method. Single administration of adriamycin, epirubicin, cisplatin (CDDP) and 5-FU, along with CDDP-5-FU combined therapy and 5-FU 1,000 mg/5 hr intermittent continuous infusion therapy, were used. Mean survival period was 719 +/- 369, 426 +/- 417, 158 +/- 125 days for groups A, B and C, respectively. One-year survival rate by degrees of H factor was comparatively examined because of different H factor rates for these 3 groups. As a result, it proved to be 83 and 40% for groups A and B, respectively, in H1,2 cases and 32 and 11% for groups B and C, respectively, in H3 cases, with their respective significant differences (p < 0.05). Positive treatment, including hepatectomy, hepatic arterial infusion chemotherapy and the like, was suggested to contribute to patient macrobiosis.

Pharmacokinetics of cis-diamminedichloroplatinum (II) given as low-dose and high-dose infusions

A pharmacokinetic analysis of cis-diamminedichloroplatinum (II) (DDP) was conducted comparing low-dose daily bolus infusions, and high-dose drip infusions. Eight patients with gastric cancer were treated with low-dose daily bolus infusions of DDP to a total daily dose of 75 mg/m2 bid for 5 days. Four patients with esophageal cancer and one patient with gastric cancer were treated with high-dose drip infusions of DDP to a total daily dose of 70-80 mg/m2. Side effects were assessed in all the patients, and the platinum concentration in plasma was determined by an atomic absorption method. The peak plasma concentration (Cmax) and area under the curve (AUC) were calculated in four cases of the low-dose therapy, and three cases of the high-dose therapy. The side effects of DDP were evaluated according to the World Health Organization (WHO) grading, paying particular attention to nausea/vomiting, appetite loss, renal toxicity, and bone marrow suppression. The incidence of nausea/vomiting and appetite loss was significantly reduced with low-dose daily bolus infusions when compared to the high-dose drip infusions. Bone marrow toxicity and renal toxicity were similar with both administration methods, although hydration was required for the high-dose drip infusions to prevent renal toxicity. The peak plasma concentration (Cmax) of total and free platinum, and the area under the curve (AUC) of total platinum, were similar with both administration methods, while the AUC of free platinum was higher with the low-dose daily bolus infusions compared to the high-dose drip infusions. The time when the concentration of total platinum was > 1 microgram per ml (holding time) was significantly longer with the high-dose drip infusions than with the low-dose daily bolus infusions. The present study suggests that low-dose daily bolus infusions of DDP would be useful in reducing gastrointestinal toxicity, without reducing the area under the curve which is important for antitumor activity.

Pharmacokinetics of cis-diamminedichloroplatinum (II) given as low-dose and high-dose infusions

A pharmacokinetic analysis of cis-diamminedichloroplatinum (II) (DDP) was conducted comparing low-dose daily bolus infusions, and high-dose drip infusions. Eight patients with gastric cancer were treated with low-dose daily bolus infusions of DDP to a total daily dose of 75 mg/m2 bid for 5 days. Four patients with esophageal cancer and one patient with gastric cancer were treated with high-dose drip infusions of DDP to a total daily dose of 70-80 mg/m2. Side effects were assessed in all the patients, and the platinum concentration in plasma was determined by an atomic absorption method. The peak plasma concentration (Cmax) and area under the curve (AUC) were calculated in four cases of the low-dose therapy, and three cases of the high-dose therapy. The side effects of DDP were evaluated according to the World Health Organization (WHO) grading, paying particular attention to nausea/vomiting, appetite loss, renal toxicity, and bone marrow suppression. The incidence of nausea/vomiting and appetite loss was significantly reduced with low-dose daily bolus infusions when compared to the high-dose drip infusions. Bone marrow toxicity and renal toxicity were similar with both administration methods, although hydration was required for the high-dose drip infusions to prevent renal toxicity. The peak plasma concentration (Cmax) of total and free platinum, and the area under the curve (AUC) of total platinum, were similar with both administration methods, while the AUC of free platinum was higher with the low-dose daily bolus infusions compared to the high-dose drip infusions. The time when the concentration of total platinum was > 1 microgram per ml (holding time) was significantly longer with the high-dose drip infusions than with the low-dose daily bolus infusions. The present study suggests that low-dose daily bolus infusions of DDP would be useful in reducing gastrointestinal toxicity, without reducing the area under the curve which is important for antitumor activity.

Antitumour activity of cis-diamminedichloroplatinum (II) against human tumour xenografts depends on its area under the curve in nude mice

A pharmacodynamic analysis of cis-diamminedichloroplatinum(II) (DDP) was conducted using two human gastric cancer xenografts, SC-1-NU and MKN-45, and one human breast cancer xenograft, MX-1, grown serially in BALB/c nu/nu mice. DDP was administered intraperitoneally (i.p.) at a total dose of 5, 10, or 20 mg/kg in a schedule of q7d x 3 or (qd x 5) x 3. DDP was also administered i.p. to BALB/c +/? mice, whose plasma was used for the assay of total and free platinum by the atomic absorption method. A total dose of 20 mg/kg DDP seemed to be the maximum tolerated dose that was effective on MX-1 and SC-1-NU. When the totally administered doses were equivalent, the antitumor effects of the q7d x 3 and (qd x 5) x 3 schedules were similar to each other. The antitumor activity of DDP against MKN-45 was dependent on the total administered dose as well as the area under the curve of free and total platinum in the plasma. Side effects were significantly reduced using a schedule of (qd x 5) x 3 in terms of body and spleen weight loss when a total of 10 or 20 mg of DDP per kg was administered. These results suggest that DDP would be useful when administered using a daily schedule for obtaining the same antitumor activity as that of bolus injection but with reduced adverse effects.

Antitumor activity of cis-diamminedichloroplatinum (II) depends on its time x concentration product against human gastric cancer cell lines in vitro

A pharmacodynamic study of cisplatin (DDP) was conducted using the gastric cancer cell lines MKN-45 and MKN-74 in vitro. Ten thousand tumor cells were incubated with 0.4-500 micrograms/ml DDP for 1-25 h, followed by recovery culture for a further 48 h. At the end of incubation, cell viability was detected by the MTT end-point, and the inhibition rate was compared in relation to the incubation time, DDP concentration, and the time X concentration product (area under the curve in vitro: AUC vitro). In both of the cell lines, the IC50 and IC90 values decreased as the exposure time increased, going a linear curve with a slope of almost -1, and showing a typical log-log AUC vitro-dependent curve. These results indicate that the antitumor activity of DDP is dependent on its AUC vitro, suggesting the clinical usefulness of this drug when administered daily in small divided doses.

Human tumors are methionine dependent in vivo

Methionine-dependence is a tumor-specific biochemical defect expressed by the inability or decreased ability of tumors to grow under the condition of methionine-depletion. Many reports have shown that methionine-dependence occurs in human tumors of all types, including fresh surgical specimens in vitro. However, in vivo determinations of methionine-dependence have thus far been made only in rodent malignant tumors using methionine-deficient diets. We report here for the first time that human cancer xenografts in nude mice are methionine-dependent and when fed a methionine-free diet tumor growth is greatly inhibited. The body weight of mice on the methionine-free diet was found to be maintainable by once-per-week administration of methionine. The data presented here suggest that methionine-dependence can be an important target for human cancer treatment.