STXBP2, encoding syntaxin-binding protein 2, is involved in intracellular organelle trafficking and is associated with familial hemophagocytic lymphohistiocytosis type 5. Although STXBP2 mutations ...reportedly cause monogenic inflammatory bowel disease, the clinical course and underlying pathogenic mechanisms remain unclear. We identified a novel mutation in STXBP2 c.1197delC, p.Ala400fs in a boy with congenital intractable diarrhea and hemophagocytic lymphohistiocytosis (HLH). HLH was treated with intravenous prednisolone, cyclosporine, and dexamethasone palmitate. Hematopoietic stem cell transplantation (HSCT) along with prophylaxis for graft-versus-host-disease was performed at 5 months of age. Additionally, colonoscopies done before and after HSCT showed mild colitis with cryptitis. The patient showed elevated fecal calprotectin levels and persistent diarrhea even after HSCT and required partial parenteral nutrition. While anti-inflammatory treatment reduced diarrhea, it was not completely normalized even after HSCT, suggesting that the pathogenesis of inflammatory bowel disease associated with STXBP2 mutations involves both hyperinflammation and functional epithelial barrier defects.
•A novel mutation in STXBP2 was found in an infant with HLH and VEO-IBD.•IBD and MVID were considered the cause of intractable diarrhea in the infant.•Infant's diarrhea improved with prednisone or other anti-inflammatory treatments.•Hematopoietic stem cell transplantation cured HLH, but diarrhea was persistent.•Functional epithelial barrier defects and hyperinflammation could have caused IBD.
HLA-haploidentical stem cell transplantation (haplo-SCT) using post-transplant high-dose cyclophosphamide (PT-CY) is an alternative choice when a suitable donors is unavailable. However, PT-CY is ...difficult in patients with Fanconi anemia (FA) due to their high vulnerability to alkylating agents. For FA, we prefer haplo-SCT by T-cell receptor αβT-cell and B-cell depletion (αβT/B-depleted haplo-SCT), which can reduce the risks of PT-CY-related complications and graft-versus-host disease (GVHD). An 11-year-old boy with diagnosed FA (
FANCG
mutation) and bone marrow failure was to receive αβT/B-depleted haplo-SCT from his father (HLA 4/8 allele matched) due to absence of an HLA-matched donors. αβT/B-depleted peripheral blood stem cells (CD34 + cell count, 1.17 × 10
7
/kg; αβ + T-cell count, 1.3 × 10
5
/kg) were infused following conditioning consisting of fludarabine (150 mg/m
2
), cyclophosphamide (40 mg/kg), anti-thymocyte globulin (5 mg/kg), rituximab (375 mg/m
2
), and thoraco-abdominal irradiation (3 Gy). Tacrolimus was used for GVHD prophylaxis until day + 30. Neutrophil engraftment was achieved on day + 9, and complete chimerism was confirmed on days + 28 and + 96. At 12-month post-SCT, the patient was well without GVHD or any other complications. αβT/B-depleted haplo-SCT is a good choice not only for patients unsuitable for PT-CY, but also for all pediatric recipients to reduce SCT-related complications.
Obstructive sleep apnea syndrome affects 1% to 2% of children. It is caused mainly by upper airway obstruction and manifests as snoring and sleep disturbance. Adenotonsillectomy can improve quality ...of life because airway obstruction occurs when both tonsils and adenoids are enlarged. We describe an 8-year-old girl with a recurrence of obstructive sleep apnea syndrome caused by hypertrophy of the tubal tonsils 4 years after adenotonsillectomy. The findings from this case highlight the importance of 1) identifying hypertrophy of the residual adenoid and compensatory hypertrophy of the tubal tonsils in patients with obstructive sleep apnea syndrome after adenotonsillectomy and 2) determining the optimal timing of adenotonsillectomy with respect to both the severity of obstructive sleep apnea and compensatory hypertrophy of other lymphoid tissue of Waldeyer's ring, as growth of such tissues is most active during the first several years of life.
LCK is a novel therapeutic target in ~40% of T-cell acute lymphoblastic leukemia (T-ALL), and dasatinib and ponatinib can act as LCK inhibitors with therapeutic effects. We herein report a ...comprehensive preclinical pharmacokinetic and pharmacodynamic evaluation of dasatinib and ponatinib in LCK-activated T-ALL. In 51 human T-ALL cases, these two drugs showed similar patterns of cytotoxic activity, with ponatinib being slightly more potent. Given orally in mice, ponatinib was associated with slower clearance with a longer T
and higher AUC
, although maximum pLCK inhibition was comparable between the two drugs. After establishing the exposure-to-response models, we simulated the steady-state pLCK inhibitory effects of each drug at currently approved dosages in humans: dasatinib at 140 mg and ponatinib at 45 mg once daily are both sufficient to achieve >50% pLCK inhibition for 13.0 and 13.9 h/day, respectively, comparable to pharmacodynamic profiles of these agents in BCR::ABL1 leukemias. Moreover, we developed a dasatinib-resistant T-ALL cell line model with LCK T316I mutation, in which ponatinib retained partial activity against LCK. In conclusion, we described the pharmacokinetic and pharmacodynamic profiles of dasatinib and ponatinib as LCK inhibitors in T-ALL, providing critical data for the development of human trials of these agents.
We report on an infant with Beals syndrome (congenital contractural arachnodactyly CCA, MIM 121050) with transient cardiomyopathy showing ballon-like dilatation of the left ventricle that was similar ...to noncompaction. The patients father and two of his brothers were also found to have CCA without cardiovascular complications. CCA, which is caused by a mutation of the gene for fibrillin 2 protein is similar to Marfan syndrome (MIM 154700), which is caused by a mutation of fibrillin 1 but produces a life-threatening cardiovascular complications. This is the first report of CCA with transient cardiomyopathy. We discuss the mechanism of the spontaneous improvement of cardiomyopathy in this case on the basis of expression of the responsible gene.
Contemporary chemotherapy for childhood acute lymphoblastic leukemia (ALL) is risk-adapted based on clinical features, leukemia genomics and minimal residual disease (MRD); however, the ...pharmacological basis of these prognostic variables remains unclear. Analyzing samples from 805 children with newly diagnosed ALL from three consecutive clinical trials, we determined the ex vivo sensitivity of primary leukemia cells to 18 therapeutic agents across 23 molecular subtypes defined by leukemia genomics. There was wide variability in drug response, with favorable ALL subtypes exhibiting the greatest sensitivity to L-asparaginase and glucocorticoids. Leukemia sensitivity to these two agents was highly associated with MRD although with distinct patterns and only in B cell ALL. We identified six patient clusters based on ALL pharmacotypes, which were associated with event-free survival, even after adjusting for MRD. Pharmacotyping identified a T cell ALL subset with a poor prognosis that was sensitive to targeted agents, pointing to alternative therapeutic strategies. Our study comprehensively described the pharmacological heterogeneity of ALL, highlighting opportunities for further individualizing therapy for this most common childhood cancer.
High hyperdiploidy, the largest and favorable subtype of childhood ALL, exhibits significant biological and prognostic heterogeneity. However, factors contributing to the varied treatment response ...and the optimal definition of hyperdiploidy remain uncertain.
We analyzed outcomes of patients treated on two consecutive frontline ALL protocols, using six different definitions of hyperdiploidy: chromosome number 51-67 (Chr51-67); DNA index (DI; DI1.16-1.6); United Kingdom ALL study group low-risk hyperdiploid, either trisomy of chromosomes 17 and 18 or +17 or +18 in the absence of +5 and +20; single trisomy of chromosome 18; double trisomy of chromosomes 4 and 10; and triple trisomy (TT) of chromosomes 4, 10, and 17. Additionally, we characterized ALL ex vivo pharmacotypes across eight main cytotoxic drugs.
Among 1,096 patients analyzed, 915 had B-ALL and 634 had pharmacotyping performed. In univariate analysis, TT emerged as the most favorable criterion for event-free survival (EFS; 10-year EFS, 97.3%
86.8%;
= .0003) and cumulative incidence of relapse (CIR; 10-year CIR, 1.4%
8.8%;
= .002) compared with the remaining B-ALL. In multivariable analysis, accounting for patient numbers using the akaike information criterion (AIC), DI1.16-1.6 was the most favorable criterion, exhibiting the best AIC for both EFS (hazard ratio HR, 0.45; 95% CI, 0.23 to 0.88) and CIR (HR, 0.45; 95% CI, 0.21 to 0.99). Hyperdiploidy and subgroups with favorable prognoses exhibited notable sensitivities to asparaginase and mercaptopurine. Specifically, asparaginase sensitivity was associated with trisomy of chromosomes 16 and 17, whereas mercaptopurine sensitivity was linked to gains of chromosomes 14 and 17.
Among different definitions of hyperdiploid ALL, DI is optimal based on independent prognostic impact and also the large proportion of low-risk patients identified. Hyperdiploid ALL exhibited particular sensitivities to asparaginase and mercaptopurine, with chromosome-specific associations.
Obstructive sleep apnea syndrome affects 1% to 2% of children. It is caused mainly by upper airway obstruction and manifests as snoring and sleep disturbance. Adenotonsillectomy can improve quality ...of life because airway obstruction occurs when both tonsils and adenoids are enlarged. We describe an 8-year-old girl with a recurrence of obstructive sleep apnea syndrome caused by hypertrophy of the tubal tonsils 4 years after adenotonsillectomy. The findings from this case highlight the importance of 1) identifying hypertrophy of the residual adenoid and compensatory hypertrophy of the tubal tonsilis in patients with obstructive sleep apnea syndrome after adenotonsillectomy and 2) determining the optimal timing of adenotonsillectomy with respect to both the severity of obstructive sleep apnea and compensatory hypertrophy of other lymphoid tissue of Waldeyer's ring, as growth of such tissues is most active during the first several years of life. (J Nippon Med Sch 2010; 77: 265-268)IntroductionObstructive sleep apnea syndrome (OSAS) is defined as intermittent cessation of airflow at both the mouth and nose during sleep.