Epigenetic deregulation of Ellis Van Creveld confers robust Hedgehog signaling in adult T-cell leukemia

One of the hallmarks of cancer, global gene expression alteration, is closely associated with the development and malignant characteristics associated with adult T-cell leukemia (ATL) as well as other cancers. Here, we show that aberrant overexpression of the Ellis Van Creveld (EVC) family is responsible for cellular Hedgehog (HH) activation, which provides the pro-survival ability of ATL cells. Using microarray, quantitative RT-PCR and immunohistochemistry we have demonstrated that EVC is significantly upregulated in ATL and human T-cell leukemia virus type I (HTLV-1)-infected cells. Epigenetic marks, including histone H3 acetylation and Lys4 trimethylation, are specifically accumulated at the EVC locus in ATL samples. The HTLV-1 Tax participates in the coordination of EVC expression in an epigenetic fashion. The treatment of shRNA targeting EVC, as well as the transcription factors for HH signaling, diminishes the HH activation and leads to apoptotic death in ATL cell lines. We also showed that a HH signaling inhibitor, GANT61, induces strong apoptosis in the established ATL cell lines and patient-derived primary ATL cells. Therefore, our data indicate that HH activation is involved in the regulation of leukemic cell survival. The epigenetically deregulated EVC appears to play an important role for HH activation. The possible use of EVC as a specific cell marker and a novel drug target for HTLV-1-infected T-cells is implicated by these findings. The HH inhibitors are suggested as drug candidates for ATL therapy. Our findings also suggest chromatin rearrangement associated with active histone markers in ATL.

Tissue-engineering-based strategies for regenerative endodontics

Stemming from in vitro and in vivo pre-clinical and human models, tissue-engineering-based strategies continue to demonstrate great potential for the regeneration of the pulp-dentin complex, particularly in necrotic, immature permanent teeth. Nanofibrous scaffolds, which closely resemble the native extracellular matrix, have been successfully synthesized by various techniques, including but not limited to electrospinning. A common goal in scaffold synthesis has been the notion of promoting cell guidance through the careful design and use of a collection of biochemical and physical cues capable of governing and stimulating specific events at the cellular and tissue levels. The latest advances in processing technologies allow for the fabrication of scaffolds where selected bioactive molecules can be delivered locally, thus increasing the possibilities for clinical success. Though electrospun scaffolds have not yet been tested in vivo in either human or animal pulpless models in immature permanent teeth, recent studies have highlighted their regenerative potential both from an in vitro and in vivo (i.e., subcutaneous model) standpoint. Possible applications for these bioactive scaffolds continue to evolve, with significant prospects related to the regeneration of both dentin and pulp tissue and, more recently, to root canal disinfection. Nonetheless, no single implantable scaffold can consistently guide the coordinated growth and development of the multiple tissue types involved in the functional regeneration of the pulp-dentin complex. The purpose of this review is to provide a comprehensive perspective on the latest discoveries related to the use of scaffolds and/or stem cells in regenerative endodontics. The authors focused this review on bioactive nanofibrous scaffolds, injectable scaffolds and stem cells, and pre-clinical findings using stem-cell-based strategies. These topics are discussed in detail in an attempt to provide future direction and to shed light on their potential translation to clinical settings.

Mutations in COG2 encoding a subunit of the conserved oligomeric golgi complex cause a congenital disorder of glycosylation

The conserved oligomeric Golgi (COG) complex is involved in intra-Golgi retrograde trafficking, and mutations in six of its eight subunits have been reported in congenital disorders of glycosylation (CDG). Here we report a patient showing severe acquired microcephaly, psychomotor retardation, seizures, liver dysfunction, hypocupremia, and hypoceruloplasminemia. Analysis of his serum glycoproteins revealed defects in both sialylation and galactosylation of glycan termini. Trio-based whole-exome sequencing identified two heterozygous mutations in COG2: a de novo frameshift mutation [c.701dup (p.Tyr234*)] and a missense mutation [c.1900T > G (p.Trp634Gly)]. Sequencing of cloned reverse-transcription polymerase chain reaction (RT-PCR) products revealed that both mutations were located on separate alleles, as expected, and that the mutant transcript harboring the frameshift mutation underwent degradation. The c.1900T > G (p.Trp634Gly) mutation is located in a domain highly conserved among vertebrates and was absent from both the public database and our control exomes. Protein expression of COG2, along with COG3 and COG4, was decreased in fibroblasts from the patient. Our data strongly suggest that these compound heterozygous mutations in COG2 are causative of CDG.

PRPF8 defects cause missplicing in myeloid malignancies

Mutations of spliceosome components are common in myeloid neoplasms. One of the affected genes, PRPF8, encodes the most evolutionarily conserved spliceosomal protein. We identified either recurrent somatic PRPF8 mutations or hemizygous deletions in 15/447 and 24/450 cases, respectively. 50% of PRPF8 mutant and del(17p) cases were found in AML and conveyed poor prognosis. PRPF8 defects correlated with increased myeloblasts and ring sideroblasts in cases without SF3B1 mutations. Knockdown of PRPF8 in K562 and CD34+ primary bone marrow cells increased proliferative capacity. Whole RNA deep sequencing of primary cells from patients with PRPF8 abnormalities demonstrated consistent missplicing defects. In yeast models, homologous mutations introduced into Prp8 abrogated a block experimentally produced in the second step of the RNA splicing process suggesting that the mutants have defects in proof-reading functions. In sum, the exploration of clinical and functional consequences suggests that PRPF8 is a novel leukemogenic gene in myeloid neoplasms with a distinct phenotype likely manifested through aberrant splicing.

De novo EEF1A2 mutations in patients with characteristic facial features, intellectual disability, autistic behaviors and epilepsy

Eukaryotic elongation factor 1, alpha-2 (eEF1A2) protein is involved in protein synthesis, suppression of apoptosis, and regulation of actin function and cytoskeletal structure. EEF1A2 gene is highly expressed in the central nervous system and Eef1a2 knockout mice show the neuronal degeneration. Until now, only one missense mutation (c.208G > A, p.Gly70Ser) in EEF1A2 has been reported in two independent patients with neurological disease. In this report, we described two patients with de novo mutations (c.754G > C, p.Asp252His and c.364G > A, p.Glu122Lys) in EEF1A2 found by whole-exome sequencing. Common clinical features are shared by all four individuals: severe intellectual disability, autistic behavior, absent speech, neonatal hypotonia, epilepsy and progressive microcephaly. Furthermore, the two patients share the similar characteristic facial features including a depressed nasal bridge, tented upper lip, everted lower lip and downturned corners of the mouth. These data strongly indicate that a new recognizable disorder is caused by EEF1A2 mutations.

Similar in vitro effects and pulp regeneration in ectopic tooth transplantation by basic fibroblast growth factor and granulocyte-colony stimulating factor

OBJECTIVES

Granulocyte-colony stimulating factor (G-CSF) has been shown to have combinatorial trophic effects with dental pulp stem cells for pulp regeneration. The aim of this investigation is to examine the effects of basic fibroblast growth factor (bFGF) in vitro and in vivo compared with those of G-CSF and to assess the potential utility of bFGF as an alternative to G-CSF for pulp regeneration.

MATERIALS AND METHODS

Five different types of cells were examined in the in vitro effects of bFGF on cell migration, proliferation, anti-apoptosis, neurite outgrowth, angiogenesis, and odontogenesis compared with those of G-CSF. The in vivo regenerative potential of pulp tissue including vasculogenesis and odontoblastic differentiation was also compared using an ectopic tooth transplantation model.

RESULTS

Basic fibroblast growth factor was similar to G-CSF in high migration, proliferation and anti-apoptotic effects and angiogenic and neurite outgrowth stimulatory activities in vitro. There was no significant difference between bFGF and G-CSF in the regenerative potential in vivo.

CONCLUSIONS

The potential utility of bFGF for pulp regeneration is demonstrated as a homing/migration factor similar to the influence of G-CSF.

Synergistic effect of 5-azacytidine and NF-κB inhibitor DHMEQ on apoptosis induction in myeloid leukemia cells

Constitutive NF-κB activation characterizes a subset of myeloid leukemia (ML) cells. Recent reports have indicated that DNA methyltransferase (DNMT) inhibitors are alternative candidates for the treatment of ML. However, the optimal use of DNMT as a chemotherapeutic agent against ML has yet to be established. In this report, we examined the effect of the NF-κB inhibitor dehydroxymethylepoxyquinomicin (DHMEQ) and its combinational use with the DNMT inhibitor 5-azacytidine (AZA) in ML cell lines. DHMEQ alone induced cell death in ML cell lines with NF-κB activation, although the response varied among the cell lines. The addition of DHMEQ enhanced the effect of AZA on the viability and apoptosis induction of ML cell lines. The treatment of ML cell lines with AZA marginally induced NF-κB binding activity, although the treatment induced NF-κB protein. These results indicate the potential usefulness of DHMEQ and its combinational use with AZA in the treatment of ML, although the molecular effect by AZA on the NF-κB pathway awaits further study.

Japanese multicenter experience of endoscopic necrosectomy for infected walled-off pancreatic necrosis: The JENIPaN study

BACKGROUND AND STUDY AIMS

Only a few large cohort studies have evaluated the efficacy and safety of endoscopic necrosectomy for infected walled-off pancreatic necrosis (WOPN). Therefore, a multicenter, large cohort study was conducted to evaluate the efficacy and safety of endoscopic necrosectomy and to examine the procedural details and follow-up after successful endoscopic necrosectomy.

PATIENTS AND METHODS

A retrospective review was conducted in 16 leading Japanese institutions for patients who underwent endoscopic necrosectomy for infected WOPN between August 2005 and July 2011. The follow-up data were also reviewed to determine the long-term outcomes of the procedures.

RESULTS

Of 57 patients, 43 (75 %) experienced successful resolution after a median of 5 sessions of endoscopic necrosectomy and 21 days of treatment. Complications occurred in 19 patients (33 %) during the treatment period. Six patients died (11 %): two due to multiple organ failure and one patient each from air embolism, splenic aneurysm, hemorrhage from a Mallory - Weiss tear, and an unknown cause. Of 43 patients with successful endoscopic necrosectomy, recurrent cavity formation was observed in three patients during a median follow-up period of 27 months.

CONCLUSIONS

Endoscopic necrosectomy can be an effective technique for infected WOPN and requires a relatively short treatment period. However, serious complications can arise, including death. Therefore, patients should be carefully selected, and knowledgeable, skilled, and experienced operators should perform the procedure. Further research into safer technologies is required in order to reduce the associated morbidity and mortality.

Japanese multicenter experience of endoscopic necrosectomy for infected walled-off pancreatic necrosis: The JENIPaN study

BACKGROUND AND STUDY AIMS

Only a few large cohort studies have evaluated the efficacy and safety of endoscopic necrosectomy for infected walled-off pancreatic necrosis (WOPN). Therefore, a multicenter, large cohort study was conducted to evaluate the efficacy and safety of endoscopic necrosectomy and to examine the procedural details and follow-up after successful endoscopic necrosectomy.

PATIENTS AND METHODS

A retrospective review was conducted in 16 leading Japanese institutions for patients who underwent endoscopic necrosectomy for infected WOPN between August 2005 and July 2011. The follow-up data were also reviewed to determine the long-term outcomes of the procedures.

RESULTS

Of 57 patients, 43 (75 %) experienced successful resolution after a median of 5 sessions of endoscopic necrosectomy and 21 days of treatment. Complications occurred in 19 patients (33 %) during the treatment period. Six patients died (11 %): two due to multiple organ failure and one patient each from air embolism, splenic aneurysm, hemorrhage from a Mallory - Weiss tear, and an unknown cause. Of 43 patients with successful endoscopic necrosectomy, recurrent cavity formation was observed in three patients during a median follow-up period of 27 months.

CONCLUSIONS

Endoscopic necrosectomy can be an effective technique for infected WOPN and requires a relatively short treatment period. However, serious complications can arise, including death. Therefore, patients should be carefully selected, and knowledgeable, skilled, and experienced operators should perform the procedure. Further research into safer technologies is required in order to reduce the associated morbidity and mortality.

Coffin-Siris syndrome is a SWI/SNF complex disorder

Coffin-Siris syndrome (CSS) is a congenital disorder characterized by intellectual disability, growth deficiency, microcephaly, coarse facial features, and hypoplastic or absent fifth fingernails and/or toenails. We previously reported that five genes are mutated in CSS, all of which encode subunits of the switch/sucrose non-fermenting (SWI/SNF) ATP-dependent chromatin-remodeling complex: SMARCB1, SMARCA4, SMARCE1, ARID1A, and ARID1B. In this study, we examined 49 newly recruited CSS-suspected patients, and re-examined three patients who did not show any mutations (using high-resolution melting analysis) in the previous study, by whole-exome sequencing or targeted resequencing. We found that SMARCB1, SMARCA4, or ARID1B were mutated in 20 patients. By examining available parental samples, we ascertained that 17 occurred de novo. All mutations in SMARCB1 and SMARCA4 were non-truncating (missense or in-frame deletion) whereas those in ARID1B were all truncating (nonsense or frameshift deletion/insertion) in this study as in our previous study. Our data further support that CSS is a SWI/SNF complex disorder.