Kohei Hashizume

High expression of Survivin, mapped to 17q25, is significantly associated with poor prognostic factors and promotes cell survival in human neuroblastoma

Survivin (SVV) is a family member of inhibitor of apoptosis proteins (IAPs) and its expression is cell cycle regulated. The gene is mapped to chromosome 17q25, the region of which is frequently gained in advanced stages of neuroblastoma (NBL). However, the role of SVV in NBL is poorly understood. Here we studied the clinical and biological role of SVV in NBL. A 1.9 kb SVV transcript was expressed in all of 9 NBL cell lines at higher levels than those in adult cancer cell lines. In 34 primary NBLs, high levels of SVV expression was significantly associated with age greater than 12 months (two sample t-test: P=0.0003), advanced stages (P=0.0136), sporadic tumors (P=0.0027) and low levels of TrkA expression (P=0.0030). In NBL cell lines, SVV mRNA expression was dramatically down-regulated in CHP134 and IMR32 cells undergoing apoptosis after treatment with all-trans retinoic acid (RA) or serum deprivation. It was only moderately decreased in cells (SH-SY5Y and CHP901) undergoing RA-induced differentiation. On the other hand, in proliferating NBL cells or RA-treated SK-N-AS line which is refractory to RA, the SVV mRNA remained at steady state levels or rather up-regulated. Furthermore, transfection of SVV into CHP134 cells induced remarkable inhibition of the RA-induced apoptosis. Collectively, our results suggest that high expression of SVV is a strong prognostic indicator for the advanced stage neuroblastomas, and that it could be one of the candidate genes for the 17q gain.

Small-for-size grafts in living-related liver transplantation

BACKGROUND The problems associated with small-for-size grafts in living-related liver transplantation are not fully understood. STUDY DESIGN A consecutive series of 79 patients underwent 80 living-related liver transplantation procedures, including one retransplant, at the University of Tokyo from January 1996 to January 2000. They were divided into two groups by graft size: graft weight/recipient standard liver volume ratios of 40% or less (n = 24), and more than 40% (n = 56). Preoperative status, mortality, morbidity, duration of hospital stay, and postoperative graft function were examined and compared between the groups. RESULTS The rate of patients who were restricted to the intensive care unit preoperatively was comparable between the groups (33% versus 21%, p = 0.27). The mean standard liver volume ratios were 37% in the small graft group and 84% in the large group. Survival rates were 80% (5 of 24) for the small graft group, which was significantly lower than that for the large group (96%, 54 of 56, p = 0.02). The rate of acute rejection was comparable between the groups (33% versus 43%, p = 0.47). Vascular complication was observed in 17% of the small graft group patients and 23% of the large group (p = 0.77). No difference was observed in the frequency of bile leakage or bile duct stenosis (25% versus 21%, p=0.77). Hyper-bilirubinemia and elongation of prothrombin time persisted longer in the small graft group than in the large group (p < 0.0001 for both). CONCLUSIONS Our surgical results may suggest that a graft weight ratio of 40% or less provides a lower chance of survival after living-related liver transplantation.

Absence of Leukotriene B4 Receptor 1 Confers Resistance to Airway Hyperresponsiveness and Th2-Type Immune Responses

Bronchial asthma is an increasingly common disorder that remains poorly understood and difficult to manage. The disease is characterized by airway hyperresponsiveness, chronic inflammation, and mucus overproduction. Based on the finding that leukotriene B4 receptor 1 (BLT1) is expressed highly in Th2 lymphocytes, we analyzed the roles of BLT1 using an OVA-induced bronchial asthma model. BLT1-null mice did not develop airway hyperresponsiveness, eosinophilic inflammation, and hyperplasia of goblet cells. Attenuated symptoms were accompanied by reduced IgE production, and accumulation of IL-5 and IL-13 in bronchoalveolar lavage fluid, suggesting attenuated Th2-type immune response in BLT1-null mice. Peribronchial lymph node cells of sensitized BLT1-null mice showed much attenuated proliferation and production of Th2 cytokines upon re-stimulation with Ag in vitro. Thus, LTB4-BLT1 axis is required for the development of Th2-type immune response, and blockade of LTB4 functions through BLT1 would be novel and useful in the effort to ameliorate bronchial asthma and related Th2-biased immune disorders.

Expression profiling and differential screening between hepatoblastomas and the corresponding normal livers: identification of high expression of the PLK1 oncogene as a poor-prognostic indicator of hepatoblastomas

Hepatoblastoma is one of the most common malignant liver tumors in young children. Recent evidences have suggested that the abnormalities in Wnt signaling pathway, as seen in frequent mutation of the β-catenin gene, may play a role in the genesis of hepatoblastoma. However, the precise mechanism to cause the tumor has been elusive. To identify novel hepatoblastoma-related genes for unveiling the molecular mechanism of the tumorigenesis, a large-scale cloning of cDNAs and differential screening of their expression between hepatoblastomas and the corresponding normal livers were performed. We constructed four full-length-enriched cDNA libraries using an oligo-capping method from the primary tissues which included two hepatoblastomas with high levels of alpha-fetoprotein (AFP), a hepatoblastoma without production of AFP, and a normal liver tissue corresponded to the tumor. Among the 10 431 cDNAs randomly picked up and successfully sequenced, 847 (8.1%) were the genes with unknown function. Of interest, the expression profile among the two subsets of hepatoblastoma and a normal liver was extremely different. A semiquantitative RT–PCR analysis showed that 86 out of 1188 genes tested were differentially expressed between hepatoblastomas and the corresponding normal livers, but that only 11 of those were expressed at high levels in the tumors. Notably, PLK1 oncogene was expressed at very high levels in hepatoblastomas as compared to the normal infants livers. Quantitative real-time RT–PCR analysis for the PLK1 mRNA levels in 74 primary hepatoblastomas and 29 corresponding nontumorous livers indicated that the patients with hepatoblastoma with high expression of PLK1 represented significantly poorer outcome than those with its low expression (5-year survival rate: 55.9 vs 87.0%, respectively, p=0.042), suggesting that the level of PLK1 expression is a novel marker to predict the prognosis of hepatoblastoma. Thus, the differentially expressed genes we have identified may become a useful tool to develop new diagnostic as well as therapeutic strategies of hepatoblastoma.

Efficacy and safety of immunization for pre- and post- liver transplant children.

Background. Infection is a serious complication after liver transplantation. Immunization is one means of controlling infections. The objective of this study was to investigate the efficacy and safety of simultaneous administration of several vaccines before transplantation and the efficacy and safety of administration under immunosuppressive conditions after transplantation. Methods. Fifty-eight patients who underwent living-related liver transplantation between April 1994 and March 2000 were included in this study. Simultaneous administration of a maximum of six vaccines was performed in a short period of time before transplantation. We also readministered vaccines to 15 patients with waning antibody titers after transplantation from June 1999. We investigated whether patients could seroconvert for measles, rubella, mumps, and varicella after immunization and how long antibody titers could be retained by measuring them several times throughout the period before and after transplantation. We also examined side effects caused by immunization. Results. The rates of seroconversion against measles, rubella, mumps, and varicella after the pretransplantation vaccination were 82%, 100%, 90%, and 95%, respectively. The rates of reseroconversion against measles, rubella, mumps, and varicella after the posttransplantation revaccination were 85%, 100%, 100%, and 71%, respectively. Although antibody titers against these viruses generally waned with time, no patient exhibited any serious illness or side effects. Conclusion. Although 12 of 58 patients (21%) had an infection, pretransplantation immunization was effective to prevent serious illness, especially for the 6 months after transplantation. Posttransplantation live-vaccine administration under immunosuppressive conditions is effective and safe.

Combination therapy with Bifidobacterium breve, Lactobacillus casei, and galactooligosaccharides dramatically improved the intestinal function in a girl with short bowel syndrome: a novel synbiotics therapy for intestinal failure.

It has been well known since ancient times that fermented milk produces beneficial effects on the consumer’s health. In the last few decades, these beneficial effects have been demonstrated to be due to the metabolic action of some bacterial species, including lactobaccilli, bifidobacteria, and streptococci (1–3). Lilly et al. first introduced the term probiotics for such bacteria in 1965 (4). Probiotics are widely used as a live microbial feed supplement that beneficially affects the host animals by improving their intestinal microbial balance (5). Additionally the term prebiotics has been adopted to refer to a nondigestive food ingredient that selectively targets the growth and/or activity of one or a limited number of bacteria in the colon and, thus, has the potential to improve host health. Several types of ingredients, such as fructooligosaccharides, galactooligosaccharides, and inulin, are used as prebiotics (2, 6). Furthermore, the combined use of probiotics and prebiotics is called synbiotics therapy, but few reports concerning synbiotics have been published (7, 8). Short bowel syndrome refers to seriously adverse symptoms that are seen in patients who have been subjected to a massive bowel resection. These patients are usually malnourished and have a dilated intestine that results in intestinal bacterial overgrowth syndrome (9, 10). Regulation of intestinal bacterial overgrowth, especially pathogenic bacterial overgrowth, is very important in patients with short bowel syndrome to attain any improvement in intestinal function. For this purpose, various antibiotics have been used to eliminate the intestinal bacteria selectively. An alternative strategy for regulating intestinal bacteria is to apply probiotics and/or prebiotics. In this report, we report the use of synbiotics therapy in the treatment of a 4-year-old girl suffering from short bowel syndrome. For the synbiotics therapy, we used Bifidobacterium breve, Lactobacillus casei, and galactooligosaccharides. This novel combination therapy was expected to act synergistically for the improvement of the subject’s health. We found that the patient’s intestinal absorptive function and motility were dramatically improved by this newly designed synbiotics therapy, and she progressed satisfactorily after 2 years of the therapy. Following the case report, we discuss the beneficial effects of the new synbiotics therapy for intestinal failure.

Role ofsurvivin, whose gene is mapped to 17q25, in human neuroblastoma and identification of a novel dominant-negative isoform,survivin-?/2B

Procedure We investigated the expression of survivin (SVV) and its isoform (SVV-β/2B) during different biological properties in neuroblastoma (NBL). Results High levels of SVV mRNA expression were significantly associated with advanced stages of NBL, diagnosis at over 1 year of age, low levels of TrkA expression, and sporadic tumors. Expression of a novel isoform, SVV-β/2B, which had an insertion of 23 amino acids within the unique BIR domain was predominant in some favorable NBLs, while it was low and ubiquitous in most normal and malignant tissues. The SVV expression wasdown-regulated during apoptosis induced by retinoic acid (RA) in CHP134 NBL cells, which was inhibited by forced expression of SVV. In contrast, SVV-β was constantly expressed during apoptosis. Like SVV ,SVV-β was also highly expressed during G2/M in a cell cycle-dependent manner, and was associated with but competed against SVV for binding with polymerized tubulin. Conclusion These data suggest that expression of SVV is a poor prognostic indicator in human NBL, and it promotes growth and survival by regulating the levels of both isoforms. Med. Pediatr. Oncol. 35:550–553, 2000.

Aberrations of the hSNF5/INI1 gene are restricted to malignant rhabdoid tumors or atypical teratoid/rhabdoid tumors in pediatric solid tumors

The hSNF5/INI1 gene, which encodes a subunit of the SWI/SNF family of chromatin‐remodeling complexes and is located at 22q11.2, has been reported as a tumor suppressor gene inactivated in malignant rhabdoid tumors (MRTs). We analyzed this gene in varieties of pediatric solid tumors including MRTs, using the reverse transcription‐polymerase chain reaction (PCR) and PCR‐single strand conformation polymorphism method. We found 5 homozygous deletions, 2 truncated mutations, one missense mutation, and one silent mutation of the hSNF5/INI1 gene in 7 MRT cell lines, and one homozygous deletion, one microdeletion, one splicing acceptor site mutation, and one absence of expression in 7 fresh tumor tissues of MRT and atypical teratoid (AT)/rhabdoid tumors (RTs). Homozygous deletions were also found in one (KYM‐1) of 8 rhabdomyosarcoma (RMS) cell lines. To investigate characteristics of the KYM‐1 cell line, we have established KYM‐1 tumors in nude mice into which KYM‐1 cells were transplanted. Notably, we found that MyoD1, known as a marker for RMS, was not expressed in the KYM‐1 cell line as well as MRT cell lines and fresh tumors. Histopathologic, cytogenetic, and molecular studies of the KYM‐1 cell line and KYM‐1 tumors in nude mice have revealed that this RMS cell line should be MRT rather than RMS. RMS‐carrying aberrations of the hSNF5/INI1 gene should be reevaluated. No aberrations of this gene were found in the other 34 cell lines or 80 fresh tumor specimens except the single nucleotide polymorphisms in the 3′ noncoding region. These results suggest that alterations of the hSNF5/INI1 gene were restricted to MRTs or AT/RTs in pediatric solid tumors.

Use of sphingosine-1-phosphate 1 receptor agonist, KRP-203, in combination with a subtherapeutic dose of cyclosporine A for rat renal transplantation.

Background. We demonstrate the long-term effectiveness of KRP-203 treatment in combination with a subtherapeutic dose of cyclosporine A (CsA) on rat renal allografts. Methods. We tested the effect of KRP-203 in combination with CsA using a rat skin allograft model. The Pharmacokinetic interaction between CsA and KRP-203 was evaluated. The selectivity of KRP-203 for sphingosine-1-phosphate (S1P)1 and S1P3 receptors were investigated in vitro. Heart rate alteration following bolus injection of phosphorylated KRP-203 (KRP-203-P) or FTY720 (FTY720-P) was also monitored in rats. Finally, the long-term effectiveness of KRP-203 in conjunction with a low dose of CsA was investigated in a rat renal transplantation model. Results. Administration of KRP-203 with CsA prolonged skin allograft survival. KRP-203 and CsA had no effect on the pharmacokinetics of the other. While FTY720-P activated both S1P1 and S1P3 receptors, KRP-203-P selectively activated S1P1, but not the S1P3 receptor (EC50: >1000 nM). Compared to FTY720-P, a tenfold higher dose of KRP-203-P was necessary to induce transient bradycardia. With a low dose of CsA (1 mg/kg/day), KRP-203 (0.3 mg/kg/day) significantly prolonged renal allograft survival (P<0.05, survival time: 9.8 days (CsA) vs. >27.4 days (CsA+KRP)). Although a higher dose of CsA (3 mg/kg/day) alone kept recipients alive, this caused severe renal graft dysfunction. Use of KRP-203 (3 mg/kg/day) in conjunction with CsA markedly improved graft function (P<0.05, creatinine clearance: 0.41±0.25 ml/min [CsA] vs. 1.15±0.16 ml/min [CsA+KRP]). Conclusions. The selectivity of KRP-203 for S1P1 reduces the risk of bradycardia, and the combination therapy of KRP-203 with CsA represents a safe and effective strategy for use in renal transplantation.

Intussusception-type antireflux valve in the Roux-en-Y loop to prevent ascending cholangitis after hepatic portojejunostomy

An intussusception-type antireflux valve was created in the Roux-en-Y loop in 23 infants with biliary atresia (17 new cases, and six others after episodes of ascending cholangitis) and 10 patients with congenital bile duct dilatation, in order to prevent ascending cholangitis after hepatic portojejunostomy. Mesenteric blood vessels were divided in a 4 cm length of the Roux-en-Y loop, and the distal 1.5 cm of this portion was further denuded of the seromuscular layer; an antireflux valve was thus established by invaginating the proximal portion into the denuded jejunum. No case, in which this technique was used, was associated with any surgical complications, and ascending cholangitis never developed in any of the 17 new cases with biliary atresia, during an average follow-up of 32 months.