Purpose Malignant peripheral nerve sheath tumors (MPNSTs) are a rare subtype of sarcoma that occur spontaneously or in association with neurofibromatosis type 1 (NF-1). This study aimed to clinically differentiate these types of MPNSTs. Materials and Methods The study reviewed 95 patients diagnosed with and treated for MPNST at Yonsei University Health System, Seoul, Korea over a 27-year period. The clinical characteristics, prognostic factors, and treatment outcomes of sporadic MPNST (sMPNST) and NF-1 associated MPNST (NF-MPNST) cases were compared. Results Patients with NF-MPNST had a significantly lower median age (32 years vs. 45 years for sMPNST, p=0.012), significantly larger median tumor size (8.2 cm vs. 5.0 cm for sMPNST, p < 0.001), and significantly larger numbers of imaging studies and surgeries (p=0.004 and p < 0.001, respectively). The 10-year overall survival (OS) rate of the patients with MPNST was 52±6%. Among the patients with localized MPNST, patients with NF-MPNST had a significantly lower 10-year OS rate (45±11% vs. 60±8% for sMPNST, p=0.046). Univariate analysis revealed the resection margin, pathology grade, and metastasis to be significant factors affecting the OS (p=0.001, p=0.020, and p < 0.001, respectively). Multivariate analysis of the patients with localized MPNST identified R2 resection and G1 as significant prognostic factors for OS.Conclusion NF-MPNST has different clinical features from sMPNST and requires more careful management. Further study will be needed to develop specific management plans for NF-MPNST.

PurposeDespite the rapid improvement in survival rate from Burkitt lymphoma and mature B-cell lymphoblastic leukemia (B-ALL) in children, a small subset of patients do not respond to first-line chemotherapy or experience relapse (RL). Herein, we report the clinical characteristics and outcomes of these patients.Materials and MethodsRL or refractory Burkitt lymphoma and mature B-ALL in 125 patients diagnosed from 1990 to 2009 were retrospectively analyzed.ResultsNineteen patients experienced RL or progressive disease (PD). Among them, 12 patients had PD or RL less than six months after initial treatment and seven had late RL. Seven patients achieved complete response (CR), 11 had PD, and one had no more therapy. Six patients who achieved CR survived without evidence of disease and four of them underwent high-dose chemotherapy (HDC) followed by stem cell transplantation (SCT). However, 11 patients who failed to obtain CR eventually died of their disease. Five-year overall survival (OS) was 31.6±10.7%. OS of patients with late RL was superior to that of patients with early RL (57.1±18.7%, vs. 16.7±10.8%, p=0.014). Achievement of CR after reinduction had significant OS (p < 0.001). OS for patients who were transplanted was superior (p < 0.01). In multivariate analysis, achievement of CR after reinduction chemotherapy showed an association with improved OS (p=0.05).ConclusionLate RL and chemotherapy-sensitive patients have the chance to achieve continuous CR using HDC/SCT, whereas patients who are refractory to retrieval therapy have poor prognosis. Therefore, novel salvage strategy is required for improvement of survival for this small set of patients.

Streptomyces griseus DSM 2608 produces bafilomycin, an antifungal plecomacrolide antibiotic. We cloned and sequenced an 87.4-kb region, including a polyketide synthase (PKS) region, methoxymalonate genes, flavensomycinate genes, and other putative regulatory genes. The 58.5kb of PKS region consisting 12 PKS modules arranged in five different PKS genes, was assumed to be responsible for the biosynthesis of plecomacrolide backbone including 16-membered macrocyclic lactone. All the modules showed high similarities with typical type I PKS genes. However, the starting module of PKS gene was confirmed to be specific for isobutyrate by sequence comparison of an acyltransferase domain. In downstream of PKS region, the genes for methoxymalonate biosynthesis were located, among which a gene for FkbH-like protein was assumed to play an important role in the production of methoxymalonyl-CoA from glyceryl-CoA. Further the genes encoding flavensomycinyl-ACP biosynthesis for the post-PKS tailoring were also found in the upstream of PKS region. By gene disruption experiments of a dehydratase domain of module 12 and an FkbH-like protein, this gene cluster was confirmed to be involved in the biosynthesis of bafilomycin.

Pectobacterium carotovorum subsp. carotovorum causes soft rot disease in various plants, including Chinese cabbage. The simple extracellular leucine-rich repeat (eLRR) domain proteins have been implicated in disease resistance. Rice leucine-rich repeat protein (OsLRP), a rice simple eLRR domain protein, is induced by pathogens, phytohormones, and salt. To see whether OsLRP enhances disease resistance to bacterial soft rot, OsLRP was introduced into Chinese cabbage by Agrobacterium-mediated transformation. Two independent transgenic lines over-expressing OsLRP were generated and further analyzed. Transgenic lines over-expressing OsLRP showed enhanced disease resistance to bacterial soft rot compared to non-transgenic control. Bacterial growth was retarded in transgenic lines over-expressing OsLRP compared to non-transgenic controls. We propose that OsLRP confers enhanced resistance to bacterial soft rot. Monitoring expression of defense-associated genes in transgenic lines over-expressing OsLRP, two different glucanases and Brassica rapa polygalacturonase inhibiting protein 2, PDF1 were constitutively activated in transgenic lines compared to non-transgenic control. Taken together, heterologous expression of OsLRP results in the activation of defense response and enhanced resistance to bacterial soft rot.

BackgroundPortal hypertensive gastropathy (PHG) is a frequently overlooked complication of liver cirrhosis (LC). The clinical implications of PHG as a prognostic factor of LC or a predictive factor for the development of hepatocellular carcinoma (HCC) have not been established. The aim of this study was to assess the clinical significance of PHG in patients with LC.MethodsPatients with LC were prospectively enrolled and followed in a single tertiary hospital in the Republic of Korea. Baseline hepatic vein pressure gradient (HVPG) was measured, and esophagogastroduodenoscopy (EGD) was performed. The associations of PHG with HVPG, survival and the development of HCC were evaluated.ResultsA total of 587 patients were enrolled. The mortality rate was 20.3 % (n = 119), and HCC developed in 9.2 % (n = 54) during the follow-up period (32.6 ± 27.8 months). The grade of PHG was well correlated with HVPG (no PGH: median 9.2 [IQR: 7.2–16.7], mild PHG: 14.6 [10.1–19.3], and severe PHG: 17.3 [12.3–21.5], P < 0.001), as well as with Child-Pugh class, MELD score or survival. However, it was not associated with the development of HCC. The grade of PHG (HR 3.29, 95 % CI: 1.12–9.63, severe vs. no PHG) and Child-Pugh class (HR 3.53, 95 % CI: 1.79–6.97, Child C vs A) showed significant associations with mortality.ConclusionPHG was well correlated with portal hypertension and could be used as a prognostic factor for LC but not for the prediction of HCC.Electronic supplementary materialThe online version of this article (doi:10.1186/s12876-016-0508-2) contains supplementary material, which is available to authorized users.