Alzheimer PHF-tau aggregates do not spread tau pathology to the brain via the Retino-tectal projection after intraocular injection in male mouse models.

Neurofibrillary tangles (NFT), a neuronal lesion found in Alzheimer's disease (AD), are composed of fibrillary aggregates of modified forms of tau proteins. The propagation of NFT follows neuroanatomical pathways suggesting that synaptically connected neurons could transmit tau pathology by the recruitment of normal tau in a prion-like manner. Moreover, the intracerebral injection of pathological tau from AD brains induces the seeding of normal tau in mouse brain. Creutzfeldt-Jacob disease has been transmitted after ocular transplants of cornea or sclera and the scrapie agent can spread across the retino-tectal pathway after intraocular injection of scrapie mouse brain homogenates. In AD, a tau pathology has been detected in the retina. To investigate the potential risk of tau pathology transmission during eye surgery using AD tissue material, we have analysed the development of tau pathology in the visual pathway of mice models expressing murine tau, wild-type or mutant human tau after intraocular injection of pathological tau proteins from AD brains. Although these pathological tau proteins were internalized in retinal ganglion cells, they did not induce aggregation of endogenous tau nor propagation of a tau pathology in the retino-tectal pathway after a 6-month incubation period. These results suggest that retinal ganglion cells exhibit a resistance to develop a tau pathology, and that eye surgery is not a major iatrogenic risk of transmission of tau pathology, contrary to what has been observed for transmission of infectious prions in prion diseases.

Bendamustine-120 plus rituximab therapy for relapsed or refractory follicular lymphoma: a multicenter phase II study.

The optimal dose, schedule, and other aspects of bendamustine plus rituximab treatment remain unclear for patients with relapsed or refractory follicular lymphoma (FL). Herein, we analyzed the efficacy of bendamustine combined with rituximab (RB-120) treatment for Japanese patients with relapsed or refractory FL. This phase II clinical trial included patients with relapsed or refractory FL who received 375 mg/m2 rituximab on day 1 and 120 mg/m2 bendamustine on days 2 and 3 every 28 days for up to 6 cycles. The primary endpoint was the overall response rate (ORR), and the secondary endpoints included the complete response (CR) rate, progression-free survival (PFS), overall survival (OS), and safety. Thirty-seven patients were enrolled in the trial (median age 62 years, range 42-75 years). All patients were previously treated with rituximab-containing chemotherapy, and 83.8% were previously treated with the R-CHOP regimen. A median of 5 cycles (range 1-6) and 48.6% of patients completed 6 cycles. The ORR was 91.9% (95% confidence interval [CI] 78.1-98.3%), with a CR rate of 86.5% (95% CI 71.2-95.5%). The 3-year PFS and OS were 70.9% (95% CI 52.3-83.3%) and 88.9% (95% CI 73.1-95.7%), respectively, with the median 39.5 months follow-up duration. The most-frequently observed grade 3/4 adverse events were hematologic: lymphopenia (95%) and neutropenia (70%). No treatment-related deaths were observed. RB-120 showed a good efficacy with equivalent toxicities, compared with the bendamustine 120 mg/m2 monotherapy. However, the problem of high drop-out incidences cannot be ignored.

Systemic Immunologic Consequences of Chronic Periodontitis.

Chronic periodontitis (ChP) is a prevalent inflammatory disease affecting 46% of the US population. ChP produces a profound local inflammatory response to dysbiotic oral microbiota that leads to destruction of alveolar bone and tooth loss. ChP is also associated with systemic illnesses, including cardiovascular diseases, malignancies, and adverse pregnancy outcomes. However, the mechanisms underlying these adverse health outcomes are poorly understood. In this prospective cohort study, we used a highly multiplex mass cytometry immunoassay to perform an in-depth analysis of the systemic consequences of ChP in patients before (n = 28) and after (n = 16) periodontal treatment. A high-dimensional analysis of intracellular signaling networks revealed immune system-wide dysfunctions differentiating patients with ChP from healthy controls. Notably, we observed exaggerated proinflammatory responses to Porphyromonas gingivalis-derived lipopolysaccharide in circulating neutrophils and monocytes from patients with ChP. Simultaneously, natural killer cell responses to inflammatory cytokines were attenuated. Importantly, the immune alterations associated with ChP were no longer detectable 3 wk after periodontal treatment. Our findings demarcate systemic and cell-specific immune dysfunctions in patients with ChP, which can be temporarily reversed by the local treatment of ChP. Future studies in larger cohorts are needed to test the boundaries of generalizability of our results.

Loss of p300 accelerates MDS-associated leukemogenesis.

The role that changes in DNA methylation and histone modifications have in human malignancies is poorly understood. p300 and CREB-binding protein (CBP), two distinct but highly homologous lysine acetyltransferases, are mutated in several cancers, suggesting their role as tumor suppressors. In the current study, we found that deletion of p300, but not CBP, markedly accelerated the leukemogenesis ofNup98-HoxD13 (NHD13) transgenic mice, an animal model that phenotypically copies human myelodysplastic syndrome (MDS). p300 deletion restored the ability of NHD13 expressing hematopoietic stem and progenitor cells (HSPCs) to self-renew in vitro, and to expand in vivo, with an increase in stem cell symmetric self-renewal divisions and a decrease in apoptosis. Furthermore, loss of p300, but not CBP, promoted cytokine signaling, including enhanced activation of the MAPK and JAK/STAT pathways in the HSPC compartment. Altogether, our data indicate that p300 has a pivotal role in blocking the transformation of MDS to acute myeloid leukemia, a role distinct from that of CBP.

Characteristic patterns of relapse after allogeneic hematopoietic SCT for adult T-cell leukemia-lymphoma: a comparative study of recurrent lesions after transplantation and chemotherapy by the Nagasaki Transplant Group.

Allogeneic hematopoietic SCT (allo-SCT) is a promising therapy that may provide long-term durable remission for adult T-cell leukemia-lymphoma (ATL) patients; however, the incidence of relapse associated with ATL remains high. To determine the clinical features of these patients at relapse, we retrospectively analyzed tumor lesions in 30 or 49 patients who relapsed following allo-SCT or chemotherapy (CHT), respectively, at three institutions in Nagasaki prefecture between 1997 and 2011. A multivariate analysis revealed that the development of abnormal lymphocytes in the peripheral blood of patients at relapse was less frequent after allo-SCT than after CHT (P<0.001). Furthermore, relapse with a new lesion only in the absence of the primary lesion was more frequent in allo-SCT (P=0.014). Lesions were more frequently observed in the central nervous systems of patients who relapsed with new lesions only (P=0.005). Thus, the clinical manifestation of relapsed ATL was slightly complex, especially in post-transplant patients. Our results emphasized the need to develop adoptive modalities for early and accurate diagnoses of relapsed ATL.

Acute leukemia during pregnancy: an investigative survey of the past 11 years.

INTRODUCTION: The management of pregnant women with acute leukemia is usually challenging. We collected data concerning pregnant women with acute leukemia in the Kanagawa area in Japan. METHODS: A questionnaire was sent to 24 institutions in the Kanagawa area. RESULTS: Data were obtained for 11 patients, median age of 31 years (range, 20-36). Eight patients had acute myeloid leukemia and three had acute lymphoblastic leukemia. Six patients were diagnosed in the first trimester of pregnancy, one in the second trimester, and four in the third trimester. Five of six patients diagnosed in the first trimester had abortions before chemotherapy, and one had an elective abortion after receiving chemotherapy. All patients diagnosed in the second or third trimester delivered live infants. Of the six patients diagnosed in the first trimester, two died of recurrent leukemia, and four remained in remission. Of the five patients diagnosed in the second or third trimester, four achieved complete remission and remained in remission. One patient died of sepsis 4 days after cesarean section. CONCLUSIONS: Careful surveillance and monitoring of the fetus and close co-operation among hematologists, gynecologists, and pediatricians are essential to successfully treat pregnant women with acute leukemia.

Expression of myeloperoxidase in acute myeloid leukemia blasts mirrors the distinct DNA methylation pattern involving the downregulation of DNA methyltransferase DNMT3B.

Myeloperoxidase (MPO) has been associated with both a myeloid lineage commitment and favorable prognosis in patients with acute myeloid leukemia (AML). DNA methyltransferase inhibitors (decitabine and zeburaline) induced MPO gene promoter demethylation and MPO gene transcription in AML cells with low MPO activity. Therefore, MPO gene transcription was directly and indirectly regulated by DNA methylation. A DNA methylation microarray subsequently revealed a distinct methylation pattern in 33 genes, including DNA methyltransferase 3 beta (DNMT3B), in CD34-positive cells obtained from AML patients with a high percentage of MPO-positive blasts. Based on the inverse relationship between the methylation status of DNMT3B and MPO, we found an inverse relationship between DNMT3B and MPO transcription levels in CD34-positive AML cells (P=0.0283). In addition, a distinct methylation pattern was observed in five genes related to myeloid differentiation or therapeutic sensitivity in CD34-positive cells from AML patients with a high percentage of MPO-positive blasts. Taken together, the results of the present study indicate that MPO may serve as an informative marker for identifying a distinct and crucial DNA methylation profile in CD34-positive AML cells.

RUNX3 interacts with MYCN and facilitates protein degradation in neuroblastoma.

RUNX3, a runt-related transcription factor, has a crucial role in dorsal root ganglion neurogenesis. Recent studies have suggested that RUNX3 acts as a tumor suppressor in stomach, colon and breast cancer. However, the biological role of RUNX3 in neuroblastoma remains elusive. Here we report that high levels of RUNX3 expression contribute to the favorable outcome in patients with neuroblastoma, whereas low levels of RUNX3 expression result in poor outcome. Array-based analysis suggested that the allelic loss at chromosome 1p36 is one of the reasons why expression of RUNX3 is downregulated in advanced neuroblastomas. Interestingly, the several patients survived from neuroblastoma with both high mRNA expressions of MYCN and RUNX3, suggesting that RUNX3 high expression might overcome the aggressive behavior of MYCN. Exogenous expression of RUNX3 strongly inhibits cell proliferation and migration in neuroblastoma cell lines. Furthermore, RUNX3 reduces the stability of MYCN protein in MYCN-amplified neuroblastoma cell lines, and this RUNX3-mediated MYCN degradation may depend on the physical interaction between RUNX3 and MYCN. Thus, our findings provide a tumor-suppressing mechanism by which RUNX3 inhibits the MYCN activity in neuroblastoma.

The diagnostic accuracy of high-resolution endoscopy, autofluorescence imaging and narrow-band imaging for differentially diagnosing colon adenoma.

BACKGROUND AND STUDY AIMS: Conventional colonoscopy can result in unnecessary biopsy or endoscopic resection due to its inability to distinguish adenomas from hyperplastic polyps. This study therefore evaluated the efficacy of high-resolution endoscopy (HRE), autofluorescence imaging (AFI), and narrow-band imaging (NBI) in discriminating colon adenoma from hyperplastic polyps. PATIENTS AND METHODS: This was a prospective multicenter study in patients undergoing AFI and NBI examinations. HRE, AFI, and NBI images were classified into two groups based on morphological characteristics, the predominant color intensities, and the visibility of meshed capillary vessels, respectively. Each of the endoscopic photographs were independently evaluated by a single endoscopist. The images were then assessed by three specialists and three residents, the latter having performed < 500 colonoscopies and < 30 NBI and AFI examinations. Diagnostic test statistics were calculated to compare the accuracy in differentiating colon adenoma from hyperplastic polyps for each method. RESULTS: A total of 183 patients were enrolled in the study and 339 adenomas and 85 hyperplastic polyps were identified. AFI and NBI could distinguish adenoma from hyperplastic polyps with an accuracy of 84.9 % and 88.4 %, respectively, whereas HRE exhibited an accuracy of 75.9 %. In the 358 lesions in which the AFI diagnosis was consistent with that of NBI, the accuracy, sensitivity, and specificity were high, at 91.9 %, 92.7 %, and 92.9 %, respectively. During the study comparing specialists and residents, AFI and NBI dramatically improved the diagnostic accuracy of residents from 69.1 % to 86.1 % and 84.7 %, respectively. CONCLUSIONS: Both AFI and NBI are considered to be feasible tools that can discriminate colon adenoma from hyperplastic polyps, and their use may be particularly beneficial for less-experienced endoscopists.

Fast on-demand droplet fusion using transient cavitation bubbles.

A method for on-demand droplet fusion in a microfluidic channel is presented using the flow created from a single explosively expanding cavitation bubble. We test the technique for water-in-oil droplets, which are produced using a T-junction design in a microfluidic chip. The cavitation bubble is created with a pulsed laser beam focused into one droplet. High-speed photography of the dynamics reveals that the droplet fusion can be induced within a few tens of microseconds and is caused by the rapid thinning of the continuous phase film separating the droplets. The cavitation bubble collapses and re-condenses into the droplet. Droplet fusion is demonstrated for static and moving droplets, and for droplets of equal and unequal sizes. Furthermore, we reveal the diffusion dominated mixing flow and the transport of a single encapsulated cell into a fused droplet. This laser-based droplet fusion technique may find applications in micro-droplet based chemical synthesis and bioassays.

Effect of glycogen synthase kinase 3 ß-mediated presenilin 1 phosphorylation on amyloid ß production is negatively regulated by insulin receptor cleavage.

Presenilin 1 (PS1), a causative molecule of familial Alzheimer's disease (AD), is known to be an unprimed substrate of glycogen synthase kinase 3 ß (GSK3ß) [Twomey and McCarthy (2006) FEBS Lett 580:4015-4020] and is phosphorylated at serine 353, 357 residues in its cytoplasmic loop region [Kirschenbaum et al. (2001) J Biol Chem 276:7366-7375]. In this report, we investigated the effect of PS1 phosphorylation on AD pathophysiology and obtained two important results--PS1 phosphorylation increased amyloid ß (Aß) 42/40 ratio, and PS1 phosphorylation was enhanced in the human AD brains. Interestingly, we demonstrated that PS1 phosphorylation promoted insulin receptor (IR) cleavage and the IR intracellular domain (IR ICD) generated by γ-secretase led to a marked transactivation of Akt (PKB), which down-regulated GSK3ß activity. Thus, the cleavage of IR by γ-secretase can inhibit PS1 phosphorylation in the long run. Taken together, our findings indicate that PS1 phosphorylation at serine 353, 357 residues can play a pivotal role in the pathology of AD and that the dysregulation of this mechanism may be causally associated with its pathology.

Induction of DNA DSB and its rejoining in clamped and non-clamped tumours after exposure to carbon ion beams in comparison to X rays.

We studied double-strand breaks (DSB) induction and rejoining in clamped and non-clamped transplanted tumours in mice leg after exposure to 80 keV µm(-1) carbon ions and X rays. The yields of DSB in the tumours were analysed by a static-field gel electrophoresis. The OER of DSB after X rays was 1.68±0.31, and this value was not changed after 1 h rejoining time (1.40±0.26). These damages in oxygenated conditions were rejoined 60-70% within 1 h in situ. No difference was found between the exposure to X rays and carbon ions for the induction and rejoining of DSB. Thus, the values of OER and rejoined fraction after exposure to carbon ions were similar to those after X rays, and the calculated relative biological effectivenesses of carbon ion were around 1 under both oxygen conditions. The yields of DSB in vivo depend on exposure doses, oxygen conditions and rejoining time, but not on the types of radiation quality.

Cytochrome P450 genetic polymorphisms influence the serum concentration of calcineurin inhibitors in allogeneic hematopoietic SCT recipients.

Calcineurin inhibitors are necessary as immunosuppressants during hematopoietic SCT (HSCT) to prevent alloreactivity, but have unfortunate toxicities. So, we investigated the association of gene polymorphisms with the initial calcineurin inhibitor concentration and the subsequent drug dose from day 1 to day 28 among patients who underwent HSCT at a single institution. We analyzed 58 serial cases of Japanese patients receiving GVHD prophylaxis with CsA (21 cases) or tacrolimus (37 cases). We investigated eight single-nucleotide polymorphisms: rs4244285 (CYP2C19), rs15524, rs4646450, rs3800959, rs776746 (CYP3A5), rs1128503, rs2032582 and rs1045642 (MDR1). The CsA concentration was significantly higher when the genotype of CYP3A5 rs15524 was T/T (P=0.044) or rs776746 was G/G (P=0.027). The CYP3A5 rs776746 and rs4646450 genotypes were also associated with tacrolimus concentration (P=0.013 and P=0.0058, respectively). The dosage of tacrolimus was remarkably reduced from day -1 to day 28 when the patient had the CYP3A5 rs4646450 C/C and/or rs776746 G/G genotype (P=0.0010 and P=0.0021, respectively). In this study, we show that genetic variation has a predictable effect on the pharmacological responses to calcineurin inhibitors in HSCT patients.

MEK-ERK-dependent multiple caspase activation by mitochondrial proapoptotic Bcl-2 family proteins is essential for heavy ion irradiation-induced glioma cell death.

Recently developed heavy ion irradiation therapy using a carbon beam (CB) against systemic malignancy has numerous advantages. However, the clinical results of CB therapy against glioblastoma still have room for improvement. Therefore, we tried to clarify the molecular mechanism of CB-induced glioma cell death. T98G and U251 human glioblastoma cell lines were irradiated by CB, and caspase-dependent apoptosis was induced in both cell lines in a dose-dependent manner. Knockdown of Bax (BCL-2-associated X protein) and Bak (BCL-2-associated killer) and overexpression of Bcl-2 or Bcl-xl (B-cell lymphoma-extra large) showed the involvement of Bcl-2 family proteins upstream of caspase activation, including caspase-8, in CB-induced glioma cell death. We also detected the activation of extracellular signal-regulated kinase (ERK) and the knockdown of ERK regulator mitogen-activated protein kinase kinase (MEK)1/2 or overexpression of a dominant-negative (DN) ERK inhibited CB-induced glioma cell death upstream of the mitochondria. In addition, application of MEK-specific inhibitors for defined periods showed that the recovery of activation of ERK between 2 and 36 h after irradiation is essential for CB-induced glioma cell death. Furthermore, MEK inhibitors or overexpression of a DN ERK failed to significantly inhibit X-ray-induced T98G and U251 cell death. These results suggested that the MEK-ERK cascade has a crucial role in CB-induced glioma cell death, which is known to have a limited contribution to X-ray-induced glioma cell death.

Salvage esophagectomy after definitive chemoradiotherapy for synchronous double cancers of the esophagus and head-and-neck.

Head-and-neck cancer is frequently associated with esophageal cancer. Because the operative procedures for these synchronous double cancers are too invasive, definitive chemoradiotherapy tends to be applied as an initial treatment. A salvage esophagectomy for either recurrent or residual disease after definitive chemoradiotherapy in patients with such double cancer has never been reported. We reviewed 21 patients with esophageal cancer who underwent a salvage esophagectomy after definitive chemoradiotherapy. Among them, the treatment course of five patients who underwent a salvage esophagectomy for patients with synchronous double cancers of the esophagus and head-and-neck region was analyzed. Because head-and-neck cancer was well controlled after chemoradiotherapy in all five patients, a salvage esophagectomy was indicated for either recurrent or residual esophageal cancer after definitive chemoradiotherapy. Anastomotic leakage developed in four patients; however, no other complications including pulmonary complications were recognized. All of them were discharged to home and three of them are still alive without any recurrence for 20-43 months. A salvage esophagectomy should be considered as a treatment option for either recurrent or residual esophageal cancer with well-controlled head-and-neck cancer after definitive chemoradiotherapy when complete resection of the esophagus is expected.

Plk1 regulates liver tumor cell death by phosphorylation of TAp63.

We previously found that Plk1 inhibited the p53/p73 activity through its direct phosphorylation. In this study, we investigated the functional role of Plk1 in modulating the p53 family member TAp63, resulting in the control of apoptotic cell death in liver tumor cells. Immunoprecipitation and in vitro pull-down assay showed that p63 binds to the kinase domain of Plk1 through its DNA-binding region. in vitro kinase assay indicated that p63 is phosphorylated by Plk1 at Ser-52 of the transactivating (TA) domain. Plk1 decreased the protein stability of TAp63 by its phosphorylation and suppressed TAp63-induced cell death. Furthermore, Plk1 knockdown in p53-mutated liver tumor cells transactivated p53 family downstream effectors, PUMA, p21(Cip1/WAF1) and 14-3-3sigma, and induced apoptotic cell death. Double knockdown of Plk1/p63 attenuated Plk1 knockdown-induced apoptotic cell death and transactivation. Intriguingly, both Plk1 and p63 are highly expressed in the side population (SP) fraction of liver tumor cells compared to non-SP fraction cells, suggesting the significance of Plk1/TAp63 in the control of cell death in tumor-initiating SP fraction cells. Thus, Plk1 controls TAp63 by its phosphorylation and regulates apoptotic cell death in liver tumor cells. Plk1/TAp63 may be a suitable candidate as a molecular target of liver tumor treatments.

A high-resolution, three-dimensional thin endoscope for fetal surgery.

BACKGROUND: Fetal surgery is receiving considerable attention. However, surgeons must have great skill to perform this surgery. For assisting with the operation, the three-dimensional (3D) endoscope is very useful because it allows the surgeon depth perception. However, the diameter of existing 3D endoscopes is approximately 10 mm. Therefore, the authors have developed a high-resolution, thin, 3D endoscope for use in fetal surgery. METHODS: The authors' system uses two 1/10-in. micro charge-coupled device (CCD) cameras at the tip of the endoscope and achieves a diameter of 5.4 mm. The endoscope's angle of convergence is 2.6 masculine, which very closely approximates the angle of convergence for humans. Thus, the surgeon experiences little visual fatigue. The view angle is 87 masculine. RESULTS: The authors compared image quality and depth perception between their system and conventional 3D and 2D endoscopes. Theoretical investigation of image quality allowed the surgeon to distinguish a line 0.2 to 0.25 mm wide. Furthermore, the depth perception with the thin 3D endoscope was almost the same as with an 11-mm normal 3D endoscope. In addition, with the 3D endoscope, a higher percentage of questions were answered correctly in the depth perception evaluation experiment in a water environment than with the 2D instrument. CONCLUSION: According to these experiments, the thin 3D endoscope has a sufficiently high image quality and depth perception even in a water environment.