Paclitaxel, ifosfamide, nedaplatin (TIN) for patients with metastatic urothelial cancer

TIN (ifosfamide 1.5 g/m2 daily for 3 days, paclitaxel 175 mg/m2, and nedaplatin 70 mg/m2 on day 1) was administered to patients with metastatic urothelial cancer previously treated by platinum-based chemotherapy and repeated every 4 weeks. Four patients received maintenance therapy, which consisted of 5'-DFUR 800 mg/day orally for 12 weeks and 1 subsequent course of TIN. This therapy regimen was repeated for 2 years from initiation of TIN. Eleven of 12 patients (91.6%) demonstrated a major response (3 complete responses, 8 partial responses), with durations of response ranging from 3 to 20 months. Progression-free survival time was from 0 to 20 months (median 8 months). One-year progression-free survival rate was 45.8%. Overall survival time was from 2 to 20 months (median 10.5 months). One-year overall survival rate was 53.5%. Grade 3/4 hematologic toxicity involved neutropenia in 100% and thrombocytopenia in 33.3%. Febrile neutropenia was observed in 5 patients (41.6%). Grade 3 nonhematologic toxicity involved malaise in 15.3%. No patient discontinued this therapy because of complications. TIN is a potent, well-tolerated regimen for previously treated patients with urothelial cancer.     

Limitin, an interferon-like cytokine, transduces inhibitory signals on B-cell growth through activation of Tyk2, but not Stat1, followed by induction and nuclear translocation of Daxx

OBJECTIVE: Limitin, an interferon-like cytokine, suppresses B lymphopoiesis through ligation of the interferon-alpha/beta (IFN-alpha/beta) receptor. The aim of this study was to examine the intracellular signal transduction pathways activated by limitin. MATERIALS AND METHODS: The effects of limitin on cell growth, the activation of Jak kinase and Stat proteins, and the induction of interferon regulatory factor-1 (IRF-1) and Daxx were examined using the mouse pre-B-cell line 18.81, wild-type, and Tyk2-deficient mouse bone marrow cells. In addition, the change of localization of the Daxx protein after limitin treatment in wild-type and Tyk2-deficient mice was examined. RESULTS: Limitin phosphorylates Tyk2, Jak1, Stat1, and Stat2 and rapidly induces IRF-1 mRNA production. Phosphorylation of Stat1 by limitin is partially dependent on Tyk2. Suppression of B-cell growth by limitin, however, is severely impaired in the absence of Tyk2, whereas it is unaffected by the absence of Stat1. Limitin also induces the expression and nuclear translocation of Daxx, which is essential for IFN-alpha-induced inhibition of B-lymphocyte development. The absence of Tyk2 abrogates this induction of Daxx expression and nuclear translocation. CONCLUSIONS: Limitin suppresses B-cell growth through activation of Tyk2, resulting in the up-regulation and nuclear translocation of Daxx. This limitin-mediated signaling pathway does not require Stat1.     

Role of thallium SPECT for evaluating the effect of maintenance chemotherapy against malignant gliomas

Thallium (Tl)-201 single-photon emission computed tomography (SPECT) is a useful tool for detecting brain tumors. In this study, we evaluated the utility of Tl-201 SPECT for determining the effect of maintenance chemotherapy with ACNU (nimustine hydrochloride)/VCR (vincristine sulfate) against malignant gliomas. The cases were comprised of 16 glioma cases; 6 astrocytomas, 2 anaplastic astrocytomas, and 8 glioblastomas. We first analyzed the correlation between Tl-201 uptake ratio and proliferative activity of the tumor, using Ki-67 immunohistochemistry in 13 cases of glioma. The uptake ratio of Tl-201 correlated with the Ki-67 staining indices (SI), and a closer correlation was obtained using Tl-201 delayed images than with the early images. We also analyzed the chronological changes of Tl-201 uptake ratio and volume of abnormal area evaluated by MRI T2-weighted imaging (MRI T2WI), in 10 cases of malignant glioma during maintenance chemotherapy. The Tl-201 uptake ratio gradually decreased with the effect of maintenance chemotherapy, and the sensitivity was superior to MRI findings. Together with MRI, Tl-201 SPECT is considered to be a useful indicator for evaluating the effect of maintenance chemotherapy against malignant gliomas.     

Bioinformatics research on inter-racial difference in drug metabolism I. Analysis on frequencies of mutant alleles and poor metabolizers on CYP2D6 and CYP2C19

The enzyme activities of CYP2D6 and CYP2C19 show a genetic polymorphism, and the frequency of poor metabolizers (PMs) on these enzymes depends on races. In the present study, the frequencies of mutant alleles and PMs in each race were analyzed based on information from published studies, considering the genetic polymorphisms of CYP2D6 and CYP2C19 as the causal factors of racial and inter-individual differences in pharmacokinetics. As a result, it was shown that there were racial differences in the frequencies of each mutant allele and PMs. The frequencies of PMs on CYP2D6 are 1.9% of Asians and 7.7% of Caucasians, and those of PMs on CYP2C19 are 15.8% of Asians and 2.2% of Caucasians. Based on the results, it was suggested that there would be racial differences in the frequencies of PM subjects whose blood concentrations might be higher for drugs metabolized by these enzymes. Additionally, it was suggested that enzyme activities would vary according to the number of functional alleles even in subjects judged to be extensive metabolizers (EMs). In the bridging study, genetic information regarding CYP2D6 and CYP2C19 of the subjects will help extrapolate foreign clinical data to a domestic population.     

Suppressed complement activation in human decay accelerating factor transgenic porcine liver cross-circulated with nonhuman primates

BACKGROUND: We developed an extracorporeal liver perfusion (ECLP) system as a liver-assist device. In this study, we evaluated the safety of the ECLP using human decay accelerating factor (hDAF) transgenic porcine livers in healthy baboons. METHODS: Livers were isolated from five hDAF transgenic pigs and five nontransgenic pigs for the ECLP. Ten cross-circulations between the ECLP and healthy baboons were performed without immunosuppressive agents. Cross-circulation was discontinued in any of the following circumstances: elevated hepatic arterial (>200 mm Hg) or portal (>60 mm Hg) perfusion pressure, massive exudate from the graft liver, mild macroscopic hemolysis, thrombocytopenia, or 24-hr well-conditioned cross-circulation. RESULTS: The cross-circulations with nontransgenic porcine livers were discontinued at 4.4+/-1.2 hr (mean+/-standard deviation) because of high perfusion pressure (n=2) or hemolysis (n=3). Three cross-circulations with hDAF transgenic porcine livers were performed for 24 hr; the other two cross-circulations were discontinued at 13 and 17 hr because of massive exudate and thrombocytopenia, respectively. The duration was 20.4+/-5.1 hr. Deposition of membrane attack complex in the hDAF transgenic porcine liver was less than that in the nontransgenic liver, although immunoglobulin-M deposition was comparable. The porcine livers showed no apparent interlobular bleeding or lobular necrosis. All porcine livers maintained bile production during the cross-circulation. No baboons showed any serious complications after the cross-circulation. CONCLUSION: The hDAF transgenic porcine liver reduced complement activation in xenoperfusion with healthy nonhuman primate blood and led to extended duration of cross-circulation.     

Symptomatic Spinal Dissemination of Malignant Astrocytoma

Object: Symptomatic spinal dissemination of malignant astrocytoma is rarely found except at autopsy. This study evaluated the clinical incidence and characteristics of spinal dissemination and the effect on outcome. Patients and methods: Patients treated for primary malignant astrocytoma, including 33 with anaplastic astrocytoma and 35 with glioblastoma, at our department between 1997 and 1999 were followed up until April 30, 2001. Head magnetic resonance (MR) imaging of all patients was obtained every 2–3 months. Signs and symptoms of leptomeningeal spread were checked at monthly outpatient examinations. Spinal MR imaging was performed if any symptoms indicating spinal dissemination were found. Results: Median survival times of patients with anaplastic astrocytoma and glioblastoma were 40.5 and 16.0 months, respectively. Seventeen patients (25%) developed intracranial dissemination and 15 of these died. Six patients (8.8%), one with anaplastic astrocytoma and five with glioblastoma, developed spinal dissemination. All patients with spinal dissemination also had intracranial dissemination. Five of the six patients died, despite systemic radiochemotherapy in four patients. All patients died of extensive whole brain and spinal dissemination or nodular mass enlargement at the upper cervical cord, not of local massive tumor progression. Conclusions: Symptomatic spinal dissemination of malignant astrocytoma is not so rare, and is the cause of death. The relatively high incidence of symptomatic leptomeningeal dissemination must be considered in the treatment of malignant astrocytomas.     

Effects of fura-2 and indo-1 on [Ca++]i in spontaneously beating cultured heart cells.

Changes in contractility and intracellular free Ca([Ca++]i) were measured in spontaneously beating cultured heart cells following exposure to indo-1 acetoxymethyl ester (indo-1AM) and fura-2 acetoxymethyl ester (fura-2AM). Although a 10 microM concentration of indo-1AM slightly decreased the beating rate, 5 and 10 microM concentrations of fura-2AM produced arrest of contraction within 10 min. However, contractility returned to normal after washing. With indo-1, the diastolic and peak systolic levels of [Ca++]i were 282 +/- 23 and 1107 +/- 122 nM, respectively, and 84 +/- 8 and 582 +/- 93 nM, respectively, with fura-2. The difference between the indo-1 and fura-2 generated responses are statistically significant (p less than 0.01). These results demonstrate that indo-1 and fura-2 can affect [Ca++]i, but the influence of indo-1 is less than that of fura-2 in the heart cells.     

Radiotherapy and tumor immunity--analysis using monoclonal antibodies

In order to better understand the immunologic effects of irradiation, blood levels of lymphocyte subsets were sequentially monitored in 37 patients before and during irradiation treatment for lung cancer. Tumor infiltrating lymphocytes induced by radiotherapy were analysed by the avidin-biotin-horseradish peroxidase method. 49 cases of head and neck cancer were examined. In some cases, remarkable infiltration of lymphocytes was observed surrounding cancer cells during radiotherapy. This infiltration was mainly composed of anti-Leu-3a + 3b positive lymphocytes, and HLA-DR positive cancer cells were remarkably observed.     

Ultracytochemical localization of acid phosphatase and trimetaphosphatase activities in the transitional epithelium of the rat urinary bladder.

Acid phosphatase and trimetaphosphatase activities have been demonstrated cytochemically in the transitional epithelium of the rat urinary bladder. Acid phosphatase activity was examined by the method of Robinson and Karnovsky (1983), and trimetaphosphatase activity was examined by the method of Kobayashi et al. (1988). Intense positive reaction for acid phosphatase activity was observed with both beta-glycerophosphate and p-nitrophenyl phosphate as substrates, in lysosomes, Golgi complex, GERL, multi-vesicular bodies and wrapping lysosomes. The reaction product of the trimetaphosphatase activity was visualized as fine particulated deposits along the limiting membrane of some lysosomes, and of tubular structures located in the basal cytoplasm. There seems to be a fine distinction and reciprocal complementary functional relationship between two kinds of lysosomes containing either acid phosphatase or trimetaphosphatase activity.     

Developmental stage-specific effects of perinatal 2,3,7,8-tetrachlorodibenzo-p-dioxin exposure on reproductive organs of male rat offspring.

Exposure to a relatively low dose of 2,3,7,8-tetrachlorodebenzo-p-dioxin (TCDD) during mid-gestation induces a reduction of ventral prostate weight in rat offspring. Recently we reported that a single administration of TCDD (12.5-800 ng/kg body weight) to pregnant Holtzman rats on gestational day (GD) 15 caused a decrease in androgen receptor (AR) mRNA level in the ventral prostate during the prepubertal period, and we proposed that this reduction of AR mRNA is one of the most sensitive adverse endpoints due to perinatal exposure to TCDD (S. Ohsako et al., 2001, TOXICOL: Sci. 60, 132-143). In the present study, to investigate the mechanism of a decrease in AR mRNA level, we administered TCDD to rats at other developmental stages and compared possible alterations of the male reproductive system. Pregnant Sprague-Dawley rats were given a single oral dose of 1 microg TCDD/kg body weight on GD 15 or GD 18, or male pups born from untreated dams were subcutaneously given a single dose of 1 microg TCDD/kg body weight on postnatal day 2 (PND 2). Offspring exposed on GD 15, GD 18, and PND 2 were sacrificed on PND 70. TCDD exposure on GD 15 resulted in significant decreases in the urogenital complex and ventral prostate weights and urogenital-glans penis length of male rat offspring, but not on GD 18 and PND 2. Testicular and epididymal weights were also lower than control group only in the TCDD-exposed GD 15 group. Anogenital distance was significantly reduced in the TCDD-exposed GD 15 and GD 18 groups, but not in the TCDD-exposed PND 2 group. Semiquantitative RT-PCR analysis showed that AR mRNA levels were decreased in the TCDD-exposed GD 15 group only, and that the constitutive level of cytochrome P450 1A1 (CYP1A1) mRNA in the ventral prostate was not changed by TCDD in any of the exposed groups. No changes in AR mRNA level were detected in the testis or brain in any of the TCDD-exposed groups. These results suggest the presence of a critical window during development with regard to impairments of male reproductive organs by in utero and lactational exposure to a low dose of TCDD.