Keiko Asami

Phase I study of irinotecan in pediatric patients with malignant solid tumors.

Purpose To determine the dose-limiting toxicity, maximum tolerated dose, and potential efficacy of irinotecan in children with refractory malignant solid tumors. Patients and Methods In the present phase I clinical trial, 28 patients received irinotecan 50 to 200 mg/m2 per day by intravenous 2-hour infusion over the course of 3 days, repeated once after an interval of 25 days. Fifty-one treatment courses were administered to these patients. Results Dose-limiting toxicities were observed at the dose of 200 mg/m2 per day for 3 days. Diarrhea and hematopoietic toxicities were the dose-limiting factors, and the former required support with intravenous fluid administration. The occurrence of vomiting was variable. Decreases in clinical tumor marker levels were observed in the majority of patients who received two cycles of irinotecan 80 mg/m2 per day to 200 mg/m2 per day over the course of 3 days, and partial response was attained in four patients who received irinotecan in two cycles of 140 mg/m2 per day to 200 mg/m2 per day over the course of 3 days. Pharmacokinetic studies showed that the plasma concentration of irinotecan and its active metabolite SN-38 ranged from 93 to 2,820 ng/mL and 5.2 to 34.8 ng/mL, respectively, during 3-day infusions of irinotecan 200 mg/m2 per day. The mean clearance of irinotecan was 14.54 L/h per m2 (range 8.45–20.83 L/h per m2). Conclusion The maximum tolerated dose was determined to be a dose of irinotecan between 160 mg/m2 per day and 180 mg/m2 per day administered over the course of 3 consecutive days on an inpatient basis, repeated once after 25 days off, and our results indicate that irinotecan is a promising anticancer agent that is worthy of phase II trials in pediatric solid tumors.

Expression of Deoxycytidine Kinase (dCK) Gene in Leukemic Cells in Childhood: Decreased Expression of dCK Gene in Relapsed Leukemia

Competitive RT-PCR was used to determine the quantitative variation in the expression of deoxycytidine kinase (dCK) gene in childhood leukemic cells. The degree of dCK gene expression varied over a 50-fold range. In two cases in which both primary and relapsed leukemic cells were analysed, decreased expression of dCK gene was found in relapsed leukemic cells. The sequence variation analysis using bisbenzimide/polyethylene glycol electrophoresis demonstrated no sequence alteration of dCK cDNA in all cases. These results indicate that the expression of dCK gene varies in patients and suggests decreased expression of the dCK gene as one of the mechanisms responsible for clinical resistance to ara-C.

Clinical impact of HLA-DR15, a minor population of paroxysmal nocturnal haemoglobinuria-type cells, and an aplastic anaemia-associated autoantibody in children with acquired aplastic anaemia

Aplastic anaemia (AA) is defined as a pancytopenia caused by bone marrow failure, and its pathogenesis is thought to involve autoimmune processes. Several predictive markers of the response to immunosuppressive therapy (IST) have been proposed, which appear to reflect the immune pathophysiology. We prospectively investigated the presence of human leucocyte antigen (HLA)‐DR15, a minor population of paroxysmal nocturnal haemoglobinuria (PNH)‐type cells, and antibodies to the recently identified autoantigen postmeiotic segregation increased 1 (PMS1) in 103 children with AA enrolled in a multicentre study. In contrast to adults, children with AA did not show an increased frequency of HLA‐DR15. In addition, a sensitive flow cytometric assay revealed that children with AA have a much lower prevalence of PNH‐type cells (21·4%) than reported for adults with this disease. An immunoblotting assay detected anti‐PMS1 antibody in 15 of 103 (14·6%) of the children. Finally, the response rate to IST was not significantly different between patients with and without DR15 (45·5% vs. 54·0%), PNH‐type cells (68·2% vs. 53·1%) or anti‐PMS1 antibody (40·0% vs. 59·1%). The current study did not confirm a correlation between these markers and the response to IST, suggesting that there is a difference in the pathophysiologies of adult and paediatric AA.

Social outcomes and quality of life of childhood cancer survivors in Japan: a cross-sectional study on marriage, education, employment and health-related QOL (SF-36).

Social outcomes and quality of life (QOL) of childhood cancer survivors (CCSs) remain unknown in Japan. We investigated these outcomes in young adult CCSs compared to those of their siblings in Japan, and analyzed the association between social outcome and SF-36 health survey subscale scores. Between 2007 and 2009, we performed a cross-sectional survey using self-rating questionnaires. We estimated social outcomes and health-related QOL by performing the SF-36 in each group: CCSs with or without stem cell transplantation (SCT)/radiotherapy (RT) and their siblings. Adjusted odds ratios for outcomes of interest were estimated using logistic regression analysis. Questionnaires from 185 CCSs and 72 CCS’s siblings were analyzed. There were no differences in educational attainment or annual income. The SF-36 subscale scores of CCSs with SCT and RT were significantly lower than those of siblings in physical functioning (PF) (p < 0.001 and 0.003, respectively) and general health (GH) (both p = 0.001). Lower PF scores correlated with recurrence (p = 0.041) and late effects (p = 0.010), and poor GH scores with late effects (p = 0.006). The CCSs had made efforts to attain educational/vocational goals; however, a significant proportion of CCSs who had experienced late effects remain at increased risk of experiencing diminished QOL.

Treatment of childhood renal cell carcinoma with lymph node metastasis: two cases and a review of literature.

Standard treatment for renal cell carcinoma (RCC) is radical nephrectomy with lymph node dissection. Stages I and II have encouraging prognoses, but Stage III with regional lymph node metastasis can be unfavorable. Adjuvant therapy for pediatric patients with advanced RCC with lymph node involvement or metastatic lesion has not been defined. Advanced pediatric RCC is reported in two patients (boys, aged 6 and 9 years: Stage IIIs, Robson; Stage III and IV, pTNM classification) treated by nephrectomy and lymph node dissection followed by postoperative interferon‐α (IFN), that can be used as an adjuvant therapy with side effects such as fever, bone marrow suppression, or decreased liver function. One is doing well for 7 years, another is suffered from lung metastases at 3 years after surgery. Although immunotherapy is expected to improve survival in pediatric patients with advanced RCC, surgical resection of renal and metastatic tumors remains the standard treatment. J. Surg. Oncol. 2000;75:266–269.

IKZF1 and CRLF2 gene alterations correlate with poor prognosis in Japanese BCR-ABL1-negative high-risk B-cell precursor acute lymphoblastic leukemia

Genome‐wide analysis studies have demonstrated that IKZF1, CRLF2, and JAK2 gene alterations correlate with poor prognosis in pediatric B‐cell precursor acute lymphoblastic leukemia (BCP‐ALL). However, the prognostic significance for these gene alterations has not been clarified in Japanese patients.

Minimal residual disease-based augmented therapy in childhood acute lymphoblastic leukemia: A report from the Japanese Childhood Cancer and Leukemia Study Group†

The majority of minimal residual disease (MRD)‐positive patients with acute lymphoblastic leukemia (ALL) have poor outcomes. The ALL2000 study was performed to evaluate the efficacy of augmented chemotherapy based on MRD‐restratification in childhood ALL.

Expression of multidrug resistance-related genes does not contribute to risk factors in newly diagnosed childhood acute lymphoblastic leukemia

Abstract Background: The present study was designed to evaluate the association of multidrug resistance gene (MDR1), multidrug resistance‐associated protein (MRP) gene and lung resistance protein (LRP) gene expression (mRNA levels) with risk factors such as phenotype, age and leukocyte count in newly diagnosed childhood acute lymphoblastic leukemia, because biological mechanisms contributing to risk factors were not known.

High serum values of soluble CD154, IL‐2 receptor, RANKL and osteoprotegerin in Langerhans cell histiocytosis

To determine useful biochemical markers in Langerhans cell histiocytosis (LCH), we analyzed the serum levels of soluble CD154 (sCD154), IL2 receptor (sIL2‐R), receptor activator of NF‐κB ligand (sRANKL), and osteoprotegerin (OPG).

Transcriptional profiling in hepatoblastomas using high-density oligonucleotide DNA array.

Hepatoblastoma is a common hepatic tumor in children. Although evidence regarding cytogenetic and molecular genetic alterations in hepatoblastomas has been reported, the molecular events affecting the biologic characteristics of this tumor, including alterations of the gene expression profile, are largely unknown. To identify genes differentially expressed between nondiseased liver (NDL) and hepatoblastoma tumor (HBT), we analyzed the gene expression profile in 14 NDL and 16 HBT samples using a high-density oligonucleotide DNA array. Using Mann-Whitney U test followed by the k-nearest neighbor algorithm, we identified 26 genes (predictor genes) that were able to assign unknown samples derived from NDL and HBT to either the NDL group or HBT group with 100% accuracy. Using a cross-validation approach, we confirmed that the k-nearest neighbor algorithm assigned the particular samples derived from NDL and HBT to either the NDL or HBT group with 93.3% (28/30 samples) accuracy. In the 26 predictor genes, we found alteration of the expression of genes regulating cell division (NAP1L1, STMN1, CCNG2, and CDC7L1) and tumor cell growth (IGF2 and IGFBP4) in HBT. Four predictor genes (ETV3, TPR, CD34, and NR1I3) were also found to be mapped to the chromosomal region 1q21 approximately q32, which has been reported to be frequently involved in the development of hepatoblastoma. The findings obtained in this study suggest that alteration of the expression of some genes regulating cell division and tumor cell growth may be characteristics of the gene expression profile in HBT, and that alteration of the expression of the four predictor genes mapped to chromosomal region 1q21 approximately q32 may also contribute to the differences in gene expression profile between NDL and HBT.