Deuterium oxide protects against myocardial injury induced by ischemia and reperfusion in rats.

Objectives. Although deuterium oxide (D2O) has preservative property on the extracted organ, whether D2O also protects the in situ myocardial injury remains unknown. Using cardiac microdialysis, local administration of D2O through dialysis probe was applied in situ rat heart. We examined the effect of the D2O on the myocardial injury induced ischemia, reperfusion, and chemical hypoxia. Methodology. We measured dialysate myoglobin levels during 30 min of coronary occlusion and reperfusion in the absence and presence of D2O. Furthermore, to confirm the effect of D2O on NaCN induced myocardial injury, we measured the dialysate myoglobin levels with local perfusion of NaCN in the absence and presence of D2O. Results. The dialysate myoglobin levels increased from 177 ± 45 ng/mL at baseline to 3030 ± 1523 ng/mL during 15-30 min of coronary occlusion and further increased to 8588 ± 1684ng/mL at 0-15 min of reperfusion. The dialysate myoglobin levels with 60 min local perfusion of NaCN increased to 1214 ± 279 ng/mL. D2O attenuated myocardial myoglobin release during 15-30 min of coronary occlusion and 0-30 min of reperfusion and 15-60 min of local perfusion of NaCN. Conclusions. D2O might have a beneficial effect of myocardium against ischemia, reperfusion and chemical hypoxia.

Residual tumor in cases of intermediate-risk neuroblastoma did not influence the prognosis.

BACKGROUND: It remains unclear whether a residual tumor mass following therapy influences the prognosis of neuroblastoma. METHODS: We retrospectively reviewed 20 patients with intermediate-risk tumors treated at our institution between 1993 and 2012 to elucidate whether additional treatment is required for residual tumors. RESULTS: The patient ages at diagnosis ranged from 0 days to 7 years. The 5-year overall survival rate was 94.4%. Thirteen patients had Stage 3 disease and seven patients had Stage 4 disease. Nine patients showed intraspinal extension. Twelve patients had a residual tumor mass at the completion of therapy, and eight showed intraspinal extension. Five of these 12 patients showed metaiodobenzylguanidine (MIBG) uptake at the end of treatment, but the uptake disappeared during the follow-up period. Except for one patient who died due to treatment complications, the rest are all alive, and nine are alive with a residual mass. We examined the residual mass in four patients and found that these tissues had differentiated into a ganglioneuroma or changed to a necrotic tissue. For the three patients with neurological symptoms at the end of treatment, some slight neurological symptoms still remained during the follow-up. Five patients with an intraspinal mass eventually presented with new symptoms. CONCLUSIONS: The presence of a residual mass at the end of treatment did not influence the patients' prognosis. Therefore, an invasive radical surgical resection and additional treatment may not be necessary. Cases with a residual intraspinal mass also require a long-term follow-up to assess the neurological prognosis.The presence of a residual mass in cases of intermediate-risk neuroblastoma at the end of treatment did not influence the patients' prognosis.

Successful treatment of infants with localized neuroblastoma based on their MYCN status.

BACKGROUND: The aim of this study was to evaluate the effectiveness of post-surgical chemotherapy for infants with localized neuroblastoma without MYCN amplification (MNA), and determine whether risk classification using MNA is reasonable. METHODS: Four hundred and fourteen eligible patients were registered between 1998 and 2004. Resectable patients in stage 1 and 2A/2B were treated by surgical resection only. Unresectable patients in stage 3 without MNA received either 6 cycles of regimen A or 3 cycles of regimen A plus 3 cycles of regimen C2; regimen A consisted of low doses of cyclophosphamide and vincristine and regimen C consisted of cyclophosphamide, vincristine and pirarubicin before surgical resection. The resectable and unresectable patients were randomly selected to receive post-surgical chemotherapy. The patients with MNA received intensive chemotherapy regimen D2, consisting of cyclophosphamide, vincristine, pirarubicin and cisplatin, and some of them received high-dose chemotherapy with stem cell transplantation. RESULTS: The 5-year event-free survival (5-EFS) rates of stage 1 and 2A/2B patients without MNA were 97.2 and 89.0% respectively (p = 0.02). A total of 31 patients in stage 3 without MNA received post-surgical chemotherapy, and 30 patients did not. The 5-EFS rates of these two groups (96.0 and 96.2%, respectively) were not significantly different (p = 0.869). The 5-EFS rate for localized patients with MNA (n = 6) was 50.0%, and that of patients without MNA was 95.0% (p < 0.001). CONCLUSION: Post-surgical chemotherapy was therefore unnecessary for localized patients without MNA. This treatment strategy using MNA is considered to be appropriate in infants.

[Effect of propranolol on dialysate myoglobin levels evoked by ischemia/reperfusion].

BACKGROUND: Although propranolol is well known to induce the preventive effect against ischemic disease, its effect on ischemia/reperfusion injuries remains unknown. We examined whether propranolol provides cardioprotection against ischemia/reperfusion injuries. METHODS: Microdialysis and 30 min of coronary artery occlusion followed by 60 min of reperfusion were applied in anesthetized rats. The dialysate myoglobin levels served as indices of myocardial injury, and were measured in the following groups: without propranolol administration (vehicle); with propranolol (2 mg x kg(-1), pro(2)-pre), (5 mg x kg(-1), pro (5) -pre) administration; zatebradine (0.5 mg x kg(-1), zat-pre) administration. Drugs were administered before coronary occlusion. RESULTS: In the pro(2)-pre, pro(5)-pre and zat-pre groups the heart rate was suppressed during the entire period. Ischemia-induced increase in dialysate myoglobin level was suppressed in the pro(2)-pre, pro(5)-pre and zat-pre groups in comparison with vehicle group. Reperfusion-induced increase in dialysate myoglobin level was suppressed in the pro(2)-pre, pro(5)-pre and zat-pre groups in comparison with vehicle group. The ratios of reperfusion/ischemia myoglobin level in pro (2)-pre and pro(5)-pre were lower than those in vehicle and zat-pre. Reperfusion-induced increase in myoglobin level was suppressed by administration of propranolol immediately before reperfusion. CONCLUSIONS: The results suggest that propranolol provides myocardial protection against ischemia/reperfusion injury. The protective effect of propranolol on reperfusion might be independent of its effect on ischemia.

The Effect on Muscle Hardness of Acupuncture Stimulation Using Low-reactive Level Laser Therapy and Silver Spike Point Therapy, along with Stretching.

BACKGROUND AND AIMS: Muscle hardness causes lower activity in athletic practice or sport competition. Increase in muscle hardness often cause injury and muscle fatigue. The aim of this study is to investigate the effect on muscle hardness of acupuncture stimulation using low-reactive level laser therapy (LLLT) and silver spike point (SSP) therapy, along with stimulation by stretching. MATERIALS SUBJECTS AND METHODS: Muscle fatigue was created experimentally, and the effect of LLLT was examined with the indices of muscle hardness and the pennation angle, using ultrasound diagnostic equipment with real-time tissue elastography (RTE) functionality. RESULTS: As a result, a combined use of stretching and SSP therapy was effective on muscle hardness, while LLLT alone had no immediate lowering of muscle hardness. In addition, only the laser stretching group demonstrated a significant decrease in the pennation angle. CONCLUSIONS: This is because an improved local blood flow due to SSP therapy is considered to have relaxed muscle tonus, which boosted metabolism and removed algogenic substances. This became more effective through a combined use of stretching and low-power laser irradiation. Moreover, it was suggested that stimulation of the acupuncture points in the crus could have a further effect on muscle hardness and the pennation angle.

Circulating methylated-DCR2 gene in serum as an indicator of prognosis and therapeutic efficacy in patients with MYCN nonamplified neuroblastoma.

BACKGROUND: MYCN amplification (MNA) in neuroblastoma is a strong indicator of poor prognosis. However, some MYCN nonamplified (non-MNA) cases show poor outcomes, and examining the status of the gene requires an operation, which may have surgical complications. Therefore, a new marker is needed to identify cases of non-MNA neuroblastomas with poor prognoses using less risky procedures. Aberrant hypermethylation of the DCR2 promoter has recently been associated with rapidly progressing neuroblastoma. We aimed to develop a noninvasive DCR2 methylation assay for patients with neuroblastoma using serum DNA, which predominantly originates from tumor-released DNA. METHODS: Using DNA-based real-time PCR, we simultaneously quantified a methylated-DCR2 specific sequence (M) and a reference sequence (R) located in the promoter region in serum DNA, and evaluated DCR2 methylation status as M/R ratios in 86 patients with neuroblastoma. RESULTS: Serum DCR2 M/R ratios were strongly correlated with those in the tumor (r=0.67; P=0.002). DCR2 methylation was associated with stage both in the whole neuroblastoma group and in the non-MNA group (P<0.001), and DCR2-methylated patients showed significantly poorer 5-year event-free survival in the whole neuroblastoma group (43% versus 84%; P<0.001), especially in the non-MNA group (12% versus 96%;P<0.001). Among five DCR2-methylated patients whose clinical courses were followed, serum M/R ratios were close to 0 in the patients in remission, whereas the ratios increased in patients who relapsed. CONCLUSIONS: Detection of methylated-DCR2 in serum DNA has promise as a noninvasive assay for predicting prognosis and therapeutic efficacy in neuroblastoma, especially in non-MNA cases. Furthermore, it might be a sensitive marker of tumor recurrence in DCR2-methylated cases.

Diversity in neuroblastomas and discrimination of the risk to progress.

The clinical diversity of Neuroblastomas (NBs) was discriminated into three groups with high sensitivity and specificity to patient's outcome. The 'high risk' NB is defined with any of following conditions, MYCN amplification or unfavorable histology of International Neuroblastoma Pathological Classification (INPC) or low Ha-ras/trk A expression. The 'low risk' NB is defined with all following conditions, single copy of MYCN and INPC favorable histology and high Ha-ras/trk A expression and localized tumor. The remaining NBs were classified into 'intermediate risk' ones. According to these criteria, the diversity of the 248 mass-screening NBs was shown with variety progressive risk; 40% were classified in low risk group, 25% were in high risk group and 35% were in intermediate risk group.

Xenon suppresses nociceptive reflex in newborn rat spinal cord in vitro; comparison with nitrous oxide.

Although analgesic action of xenon has been reported, little is known about the effect of xenon at the spinal cord, which plays a crucial role in nociceptive transmission. We studied the effect of xenon on nociceptive reflex (the slow ventral root potential) and the monosynaptic reflex in neonatal rat spinal cord in vitro in comparison with nitrous oxide. Xenon (30%) and nitrous oxide (30%) were applied for 17 min through superfusing artificial cerebrospinal fluid. Xenon and nitrous oxide significantly reduced the amplitude of nociceptive reflex by approximately 70% and approximately 25%, respectively. Xenon and nitrous oxide also significantly reduced the amplitude of the monosynaptic reflex by approximately 35% and approximately 15%, respectively. These results indicate that xenon suppressed the synaptic transmission at the spinal cord, especially those of the slow ventral root potential, which reflect nociceptive transmission.

Stimulation of N-methyl-D-aspartate (NMDA) receptors inhibits neuronal migration in embryonic cerebral cortex: a tissue culture study.

We performed a tissue culture study using embryonic rat brain to investigate the effect of excessive stimulation of NMDA receptors on neuronal migration in the cerebral cortex. After progenitor cells in the ventricular zone of E16 cerebral cortex explants were labeled with [(3)H]thymidine, the explants were cultured for 48 h, and distributions of labelled cells were evaluated autoradiographically. Stimulation of NMDA receptors by NMDA and ibotenate, NMDA receptor agonists added to the culture medium in separate studies, caused percentages of labeled cells to decrease significantly in the intermediate zone and increase in the ventricular zone. The results suggest that in rat cerebral cortex, agonist stimulation of NMDA receptors inhibits neuronal migration.

Is the prognosis of stage 4s neuroblastoma in patients 12 months of age and older really excellent?

PURPOSE: In the International Neuroblastoma Risk Group (INRG) classification system, stage 4s was changed into stage MS in children less than 18 months of age. Stage MS is defined as a metastatic disease with skin, liver and bone marrow, similar to INSS stage 4s. To evaluate the outcome of stage 4s cases in patients 12 months of age and over and to determine the appropriate treatment strategy. METHOD: We performed a retrospective review of 3834 patients registered with the Japanese Society of Pediatric Oncology and Japanese Society of Pediatric Surgeons between 1980 and 1998. RESULTS: The rates of stage 4s patients were 10.7%, 6.3% and 3.3% in patients of ≥ 11 months of age, from ≥ 12 to ≤ 17 months of age, ≥ 18 months of age, respectively. The 5 year event-free survival rates were 89.4%, 100% and 53.1%, respectively. The rates of MYCN amplification and unfavourable histology were smaller in stage 4s groups than stage 4 groups in all ages. CONCLUSION: In the children 12 months of age and older, stage 4s cases are markedly different from stage 4 cases in regard to the clinical features and prognosis. The prognosis of stage 4s cases from ≥ 12 to ≤ 17months of age is excellent. The concept of stage MS appears to be appropriate.

Identification of therapy-sensitive and therapy-resistant neuroblastoma subtypes in stages III, IVs and IV.

The aim was to present a new model of risk stratification with high predictive sensitivity for non-localized neuroblastomas (NBs). "MYCN amplification", "unfavorable histology of the International Neuroblastoma Pathology Classification (INPC) system" and "low Ha-ras/trk A expression" could be defined as an independent predictor for high-risk NBs. A risk stratification flow chart was applied to 103 advanced NBs in which all three factors were examined and 69 were grouped as high-risk NBs of which 38 patients died. The predictive sensitivity for poor patient outcome was 86%, which included 38 of the 44 total deaths in this analysis. Using the number of the three independent risk factors in each tumor, the 69 high-risk NBs were classified into three subgroups. NBs with the three risk factors (triple risk) represented the most aggressive character and survival of the affected patients was only 10% ("therapy-resistant NBs"). Survivals of the patients with NBs possessed the two (double) risk factors or the one (single) risk factor were 29% and 66%, respectively. This stratification also elucidated a subgroup in which patient survival was 90% ("therapy-sensitive"). There were 21 NBs with "high Ha-ras/trk A expression", "favorable INPC histology" and "unamplified MYCN" (no risk NBs). Among the four subgroups without a risk factor, with a single risk factor, with double risk and with triple risk, Kaplan-Meier analysis showed a significant difference in NB patient outcome (p<0.0001). Risk stratification might improve the therapeutic efficacy for the high-risk NBs and might decrease therapy-related sequelae in the lower risk NBs.

Preoperative analysis of 11q loss using circulating tumor-released DNA in serum: a novel diagnostic tool for therapy stratification of neuroblastoma.

Allelic deletion of the long arm of chromosome 11 (11q loss) is closely associated with the prognosis of neuroblastoma (NB). Here we examined 11q loss using tumor-released DNA fragments in the sera of 24 cases. The allelic intensity score of a panel of polymorphic markers in 11q23 in serum DNA was significantly different between the 11q loss-positive group and the11q loss-negative group. The 11q loss-positive and -negative groups did not overlap when a cut-off value of 0.5 was chosen for the allelic intensity score. Our serum-based 11q loss analysis could predict the allelic status of 11q in tumors.

A novel PAX3 rearrangement in embryonal rhabdomyosarcoma.

Rhabdomyosarcoma is the most common soft tissue tumor seen in children and young adults, and it can be classified into 2 major histological subtypes, alveolar and embryonal. In the alveolar subtype, 2 recurrent chromosomal translocations, t(2;13)(q35;q14) and its variant t(1;13)(p36;q14), have been identified as the specific cytogenetic abnormalities. These translocations produce the PAX3-FOXO1 and PAX7-FOXO1 fusion genes, respectively. In the embryonal subtype, however, no recurrent chromosomal abnormalities have been identified. In this study, we analyzed the complex chromosomal translocation in one case with embryonal rhabdomyosarcoma by means of spectral karyotyping (SKY) and identified a novel translocation involving chromosome band 2q35, which is the locus of PAX3 gene. Furthermore, we identified the novel PAX3 rearrangement using fluorescence in situ hybridization (FISH) analysis. Additional identification of the partner gene may help disclose the molecular mechanism of the development of this embryonal subtype.

A review of 331 rhabdomyosarcoma cases in patients treated between 1991 and 2002 in Japan.

BACKGROUND: To prepare for a Japanese nationwide group study of patients with rhabdomyosarcoma (RMS), we examined the characteristics and outcomes of RMS patients treated recently in Japan. METHODS: We classified 331 RMS patients treated between 1991 and 2002 at 63 institutions according to the Intergroup Rhabdomyosarcoma Study V (IRS-V) risk-group classification. RESULTS: Ten-year survival rates were 86.3% for patients in low-risk subgroup A, 80.7% for low-risk subgroup B, 62.7% for intermediate-risk subgroup A, 61.7% for intermediate-risk subgroup B, and 38.1% for the high-risk group. The outcomes of the patients in the former three groups were 8%, 12%, and 21% worse than the outcomes of the respective patients in the IRS-III and early IRS-IV data. The frequency of the alveolar histological subtype was 21.8%. Chimera genes, which are useful markers for the alveolar subtype, had been examined in only 10% of the patients treated in the period of this investigation. The survival rates of our patients with embryonal and alveolar histological subtypes (65.9% and 63.4%, respectively) were not significantly different. Among the patients in the high-risk group, the 5-year survival of patients who received high-dose chemotherapy (HDC; 58.2%) was significantly better than that of patients who did not receive HDC (18.4%). CONCLUSION: Patients in the lower-risk groups with embryonal-type tumors had poorer outcomes in this retrospective study. The better outcome of patients in the high-risk group is apparently due to the outstanding results obtained with an HDC regimen in a single institution. These results suggest that there is a need for: (1) a standard therapy, (2) a rapid central pathology review including a chimera gene analysis for the lower-risk group, and (3) evaluation of the efficacy of the high-dose regimen for the high-risk group in Japan.

Regression of refractory rhabdomyosarcoma after allogeneic stem-cell transplantation.

A 17-year-old girl developed refractory rhabdomyosarcoma. An allogeneic peripheral-blood stem-cell transplant was performed after a myeloablative regimen. Although rapid disease progression had resolved transiently, after the start of high-dose chemotherapy, re-progression was apparently observed from day 14. However, delayed tumor regression occurred on day 30, shortly after the reduction of immunosuppressants. She achieved a partial remission. The second tumor regression provides suggestive clinical evidence that graft-versus-tumor effect may occur against rhabdomyosarcoma. Although further investigation is required, allogeneic stem-cell transplantation could provide a new therapeutic option for refractory rhabdomyosarcoma.

Intensified chemotherapy increases the survival rates in patients with stage 4 neuroblastoma with MYCN amplification.

PURPOSE: Patients with high-risk neuroblastoma who have multiple copies of MYCN fare much worse than do those without MYCN amplification; however, it has not been clarified whether intensified chemotherapy with or without blood stem cell transplantation can alter the extremely poor prognosis of patients with amplified MYCN. METHODS AND RESULTS: Between 1985 and 1999, 301 patients older than age 12 months with stage 4 neuroblastoma were treated. From January 1985 to February 1991, 80 patients with stage 4 neuroblastoma with and without MYCN amplification uniformly received induction chemotherapy with regimen A(1) (cyclophosphamide 1,200 mg/m(2) and vincristine 1.5 mg/m(2) on day 1, tetra-hydropyranyl [THP]-Adriamycin 40 mg/m(2) on day 3, and cisplatin 90 mg/m(2) on day 5). Among 22 patients with MYCN amplification, nine (40.9%) achieved a complete remission and seven (31.8%) underwent stem cell transplantation. Of 58 patients without MYCN amplification, 43 (74.1%) achieved a complete remission and 14 (24.1%) underwent stem cell transplantation. The 5-year relapse-free survival rates were 23.2% for stage 4 patients with MYCN amplification and 33.3% for those without MYCN amplification (P = 0.029); the 5-year overall survival rates were 32.8% for stage 4 patients with MYCN amplification and 42.8% for those without MYCN amplification (P > 0.05). From March 1991 to June 1998, patients with stage 4 neuroblastoma who had 10 or more copies of MYCN were treated with regimen A(3) (cyclophosphamide 1,200 mg/m(2) per day on days 1 and 2, THP-Adriamycin 40 mg/m(2) on day 3, etoposide 100 mg/m(2) per day on days 1 to 5, and cisplatin 25 mg/m(2) per day on days 1 to 5); those with fewer than 10 copies of MYCN received regimen new A (cyclophosphamide 1,200 mg/m on day 1, THP-Adriamycin 40 mg/m on day 3, etoposide 100 mg/m per day on days 1 to 5, and cisplatin 90 mg/m on day 5), which is similar in intensity to regimen A. Among 88 patients with MYCN amplification, 63 (71.6%) achieved a complete remission and 63 (71.68%) underwent stem cell transplantation. Of 133 patients without MYCN amplification, 93 (69.9%) achieved a complete remission and 71 (53.4%) underwent stem cell transplantation. The 5-year relapse-free survival rates were 36.0% for stage 4 patients with MYCN amplification and 32.2% for those without MYCN amplification (P > 0.05), the 5-year overall survival rates were 34.0% for stage 4 patients with MYCN amplification and 38.9% for those without MYCN amplification (P > 0.05). The difference in relapse-free survival rates was significantly different (P = 0.003) between patients with MYCN-amplified tumor treated before (regimen A(1)) versus after 1991 (regimen A(3)). CONCLUSIONS: With the use of the more intensive induction regimen A plus blood stem cell transplantation for MYCN-amplified patients, survival curves for those with or without MYCN amplification now appear similar. Higher doses of chemotherapy may ameliorate the effect of MYCN amplification in patients with high-risk neuroblastoma.

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.