Sub-lethal doses of chemotherapeutic agents induce senescence in T cells and upregulation of PD-1 expression

Cellular senescence is a stable cell cycle arrest, usually in response to internal and/or external stress, including telomere dysfunction, abnormal cellular growth, and DNA damage. Several chemotherapeutic drugs, such as melphalan (MEL) and doxorubicin (DXR), induce cellular senescence in cancer cells. However, it is not clear whether these drugs induce senescence in immune cells. We evaluated the induction of cellular senescence in T cells were derived from human peripheral blood mononuclear cells (PBMNCs) in healthy donors using sub-lethal doses of chemotherapeutic agents. The PBMNCs were kept overnight in RPMI 1640 medium with 2% phytohemagglutinin and 10% fetal bovine serum and then cultured in RPMI 1640 with 20 ng/mL IL-2 and sub-lethal doses of chemotherapeutic drugs (2 μM MEL and 50 nM DXR) for 48 h. Sub-lethal doses of chemotherapeutic agents induced phenotypes associated with senescence, such as the formation of γH2AX nuclear foci, cell proliferation arrest, and induction of senescence-associated beta-galactosidase (SA-β-Gal) activity, (control vs. MEL, DXR; median mean fluorescence intensity (MFI) 1883 (1130-2163) vs. 2233 (1385-2254), 2406.5 (1377-3119), respectively) in T cells. IL6 and SPP1 mRNA, which are senescence-associated secretory phenotype (SASP) factors, were significantly upregulated by sublethal doses of MEL and DXR compared to the control (P = 0.043 and 0.018, respectively). Moreover, sub-lethal doses of chemotherapeutic agents significantly enhanced the expression of programmed death 1 (PD-1) on CD3 + CD4 + and CD3 + CD8 + T cells compared to the control (CD4 + T cells; P = 0.043, 0.043, and 0.043, respectively, CD8 + T cells; P = 0.043, 0.043, and 0.043, respectively). Our results suggest that sub-lethal doses of chemotherapeutic agents induce senescence in T cells and tumor immunosuppression by upregulating PD-1 expression on T cells.

DNA damage-induced cellular senescence is regulated by 53BP1 accumulation in the nuclear foci and phase separation

Cellular senescence is linked to a wide range of age-related diseases and can be triggered by a variety of stresses, including DNA damage. A variety of genotoxic stressors, such as anti-cancer drugs, cause DNA double-strand breaks (DSBs), which trigger the accumulation of the tumour suppressor protein p53 in the nucleus. Cellular stresses stabilize and activate the p53 signalling pathway, which regulates various cellular processes, such as apoptosis, DNA repair, and senescence. Although p53 signalling is a well-known tumour suppressor pathway, it remains unclear how it is regulated during cellular senescence. Here, we show that p53-binding protein 1 (53BP1) accumulation in the nuclear foci is required for DNA damage-induced cellular senescence via p53 activation. In human immortalized fibroblast, shRNA-mediated 53BP1 depletion decreased not only the expression of p53-target genes but also the cellular senescence induced by adriamycin treatment. Furthermore, we confirmed that DSBs trigger the hyperaccumulation of 53BP1 in the nuclear foci, which plays a key role in the regulation of cellular senescence. To prevent the accumulation of 53BP1 in the nuclear foci, we used phase separation inhibitors, and siRNA against RNF168, which accumulates at DSB loci and forms complexes with 53BP1. This blocks the formation of 53BP1 nuclear foci and DNA damage-induced cellular senescence by activating the p53 signaling pathway. In conclusion,   we demonstrated that increased accumulation of 53BP1 in the nuclear foci following DNA damage activates p53 and governs cellular senescence via a liquid-liquid phase separation mechanism.

MYC Causes Multiple Myeloma Progression via Attenuating TP53-Induced MicroRNA-34 Expression

MicroRNAs (miRNAs and miRs) are small (19-25 base pairs) non-coding RNAs with the ability to modulate gene expression. Previously, we showed that the miR-34 family is downregulated in multiple myeloma (MM) as the cancer progressed. In this study, we aimed to clarify the mechanism of miRNA dysregulation in MM. We focused particularly on the interaction between MYC and the TP53-miR34 axis because there is a discrepancy between increased TP53 and decreased miR-34 expressions in MM. Using the nutlin-3 or Tet-on systems, we caused wild-type (WT) p53 protein accumulation in human MM cell lines (HMCLs) and observed upregulated miR-34 expression. Next, we found that treatment with an Myc inhibitor alone did not affect miR-34 expression levels, but when it was coupled with p53 accumulation, miR-34 expression increased. In contrast, forced MYC activation by the MYC-ER system reduced nutlin-3-induced miR-34 expression. We also observed that TP53 and MYC were negatively correlated with mature miR-34 expressions in the plasma cells of patients with MM. Our results suggest that MYC participates in the suppression of p53-dependent miRNA expressions. Because miRNA expression suppresses tumors, its inhibition leads to MM development and malignant transformation.

DNA-double strand breaks enhance the expression of major histocompatibility complex class II through the ATM-NF-κΒ-IRF1-CIITA pathway

Major histocompatibility complex class II (MHC II) is important for the adaptive immune response because MHC II presents processed antigens to a cluster of differentiation 4 (CD4)-positive T-cells. Conventional doses of chemotherapeutic agents induce tumor cell death by causing DNA double-strand breaks (DSBs). However, cellular responses caused by sub-lethal doses of chemotherapeutic agents are poorly understood. In this study, using low doses of chemotherapeutic agents, we showed that DSBs enhanced the expression of MHC II on cells that originate from antigen-presenting cells (APCs). These agents induced the MHC class II transactivator (CIITA), the master regulator of MHC II, and interferon regulatory factor 1 (IRF1), a transcription factor for CIITA. Short hairpin RNA against IRF1 suppressed chemotherapeutic agent-induced CIITA expression, whereas exogenous expression of IRF1 induced CIITA. Inhibition of ataxia-telangiectasia mutated (ATM), a DSB-activated kinase, suppressed induction of IRF1, CIITA, and MHC II. Similar results were observed by inhibiting NF-κB, a downstream target of ATM. These results suggest that DSBs induce MHC II activity via the ATM-NF-κB-IRF1-CIITA pathway in cells that intrinsically present antigens. Additionally, chemotherapeutic agents induced T-cell regulatory molecules. Our findings suggest that chemotherapeutic agents enhance the antigen presentation activity of APCs for T-cell activation.

Sterile inflammation through Ca2+/ Calmodulin-dependent protein kinase II signaling is essential for adverse cardiac remodeling

Introduction and hypothesis

Sterile inflammation is associated with cardiac remodeling in response to non-ischemic stress, but how it is initiated in the absence of cell death and how it is propagated are not well elucidated. We tested the hypothesis that activation of CaMKII in cardiomyocytes and macrophages in response to pressure overload initiates inflammatory responses leading to adverse cardiac remodeling.

Methods and results

Cardiomyocyte specific CaMKIIδ knockout (CKO) mice were subjected to transverse aortic constriction (TAC). CaMKII and NFkB activation were significantly increased in control fl/fl (CTL) but not in CKO hearts. Cardiac mRNA levels for pro-inflammatory cytokines also increased vs sham. These responses were significantly attenuated in the CKO mice. Activated NLRP3 inflammasome was shown by elevated caspase-1 activity in isolated cardiomyocytes of CTL while attenuated in CKO. Macrophage accumulation was attenuated in the CKO and NLRP3 inhibitor MCC950 treated mice. Cardiac fibrosis and subsequent cardiac dysfunction were less impaired in the CKO vs CTL (ejection fraction 43±3% vs 33±5%). Upregulated NLRP3 gene expression, elevated CaMKII and caspase-1 activity were observed in neonatal mouse cardiomyocytes (NMCMs) in response to osmotic stretch. Increased caspase-1 activity was observed in macrophages cultured with media from osmotic-stretched NMCMs and it was attenuated by pretreatment of CaMKII inhibitor KN-93. Coincubation with stretched NMCMs induced inflammatory responses in isolated macrophages from wild-type mice but not in isolated macrophages from KN-93 pretreated mice.

Conclusions

Activated CaMKIIδ in response to pressure overload triggers inflammatory signals including NLRP3 inflammasome cascade in cardiomyocytes. CaMKII could also contribute amplification of inflammasome signal in macrophages leading fibrosis and consequent cardiac dysfunction. CaMKII in cardiomyocytes and macrophages could be a therapeutic target to prevent progression of non-ischemic heart failure.

Funding Acknowledgement

Type of funding sources: None.

DNA Damage Response in Multiple Myeloma: The Role of the Tumor Microenvironment

Multiple myeloma (MM) is an incurable plasma cell malignancy characterized by genomic instability. MM cells present various forms of genetic instability, including chromosomal instability, microsatellite instability, and base-pair alterations, as well as changes in chromosome number. The tumor microenvironment and an abnormal DNA repair function affect genetic instability in this disease. In addition, states of the tumor microenvironment itself, such as inflammation and hypoxia, influence the DNA damage response, which includes DNA repair mechanisms, cell cycle checkpoints, and apoptotic pathways. Unrepaired DNA damage in tumor cells has been shown to exacerbate genomic instability and aberrant features that enable MM progression and drug resistance. This review provides an overview of the DNA repair pathways, with a special focus on their function in MM, and discusses the role of the tumor microenvironment in governing DNA repair mechanisms.

Long Noncoding RNA PVT1 Is Regulated by Bromodomain Protein BRD4 in Multiple Myeloma and Is Associated with Disease Progression

Long noncoding RNAs (lncRNAs) are deregulated in human cancers and are associated with disease progression. Plasmacytoma Variant Translocation 1 (PVT1), a lncRNA, is located adjacent to the gene MYC, which has been linked to multiple myeloma (MM). PVT1 is expressed in MM and is associated with carcinogenesis. However, its role and regulation remain uncertain. We examined PVT1/MYC expression using real-time PCR in plasma cells purified from 59 monoclonal gammopathy of undetermined significance (MGUS) and 140 MM patients. The MM cell lines KMS11, KMS12PE, OPM2, and RPMI8226 were treated with JQ1, an MYC super-enhancer inhibitor, or MYC inhibitor 10058-F4. The expression levels of PVT1 and MYC were significantly higher in MM than in MGUS (p < 0.0001) and were positively correlated with disease progression (r = 0.394, p < 0.0001). JQ1 inhibited cell proliferation and decreased the expression levels of MYC and PVT1. However, 10054-F4 did not alter the expression level of PVT1. The positive correlation between MYC and PVT1 in patients, the synchronous downregulation of MYC and PVT1 by JQ1, and the lack of effect of the MYC inhibitor on PVT1 expression suggest that the expression of these two genes is co-regulated by a super-enhancer. Cooperative effects between these two genes may contribute to MM pathogenesis and progression.

PARP1 V762A polymorphism affects the prognosis of myelodysplastic syndromes

OBJECTIVE

Myelodysplastic syndromes (MDS), caused by various genetic mutations in hematopoietic stem cells, are associated with highly variable outcomes. Poly (ADP-ribose) polymerase-1 (PARP1) plays an important role in DNA damage repair and contributes to the progression of several types of cancer. Here, we investigated the impact of PARP1 V762A polymorphism on the susceptibility to and prognosis of MDS.

METHODS

Samples collected from 105 MDS patients and 202 race-matched healthy controls were subjected to polymerase chain reaction-restriction fragment length polymorphism for genotyping.

RESULTS

The allele and genotype frequencies of PARP1 V762A did not differ between MDS patients and the control group. However, MDS patients with the PARP1 V762A non-AA genotype, which is associated with high gene activity, had shorter overall survival rates (P = .01) than those with the AA genotype. Multivariate analysis of overall survival also revealed PARP1 V762A non-AA genotype as a poor prognostic factor (P = .02). When patients were analyzed according to treatment history, the PARP1 V762A non-AA genotype was only associated with poor survival in patients who had received treatment (P = .02).

CONCLUSION

PARP1 V762A polymorphism may be an independent prognostic factor for MDS, and a predictive biomarker for MDS treatment.

Integrin α7 and Extracellular Matrix Laminin 211 Interaction Promotes Proliferation of Acute Myeloid Leukemia Cells and Is Associated with Granulocytic Sarcoma

Acute myeloid leukemia (AML) with granulocytic sarcoma (GS) is characterized by poor prognosis; however, its underlying mechanism is unclear. Bone marrow samples from 64 AML patients (9 with GS and 55 without GS) together with AML cell lines PL21, THP1, HL60, Kasumi-1, and KG-1 were used to elucidate the pathology of AML with GS. RNA-Seq analyses were performed on samples from seven AML patients with or without GS. Gene set enrichment analyses revealed significantly upregulated candidates on the cell surface of the GS group. Expression of the adhesion integrin α7 (ITGA7) was significantly higher in the GS group, as seen by RT-qPCR (p = 0.00188) and immunohistochemistry of bone marrow formalin-fixed, paraffin-embedded (FFPE) specimens. Flow cytometry revealed enhanced proliferation of PL21 and THP1 cells containing surface ITGA7 in the presence of laminin 211 and stimulated ERK phosphorylation; this effect was abrogated following ITGA7 knockdown or ERK inhibition. Overall, high ITGA7 expression was associated with poor patient survival (p = 0.0477). In summary, ITGA7 is highly expressed in AML with GS, and its ligand (laminin 211) stimulates cell proliferation through ERK signaling. This is the first study demonstrating the role of integrin α7 and extracellular matrix interactions in AML cell proliferation and extramedullary disease development.

Fluxes of Atmospheric Greenhouse-Gases in Maryland (FLAGG-MD): Emissions of Carbon Dioxide in the Baltimore, MD-Washington, D.C. area

To study emissions of CO2 in the Baltimore, MD-Washington, D.C. (Balt-Wash) area, an aircraft campaign was conducted in February 2015, as part of the FLAGG-MD (Fluxes of Atmospheric Greenhouse-Gases in Maryland) project. During the campaign, elevated mole fractions of CO2 were observed downwind of the urban center and local power plants. Upwind flight data and HYSPLIT (Hybrid Single Particle Lagrangian Integrated Trajectory) model analyses help account for the impact of emissions outside the Balt-Wash area. The accuracy, precision, and sensitivity of CO2 emissions estimates based on the mass balance approach were assessed for both power plants and cities. Our estimates of CO2 emissions from two local power plants agree well with their CEMS (Continuous Emissions Monitoring Systems) records. For the 16 power plant plumes captured by the aircraft, the mean percentage difference of CO2 emissions was -0.3 %. For the Balt-Wash area as a whole, the 1σ CO2 emission rate uncertainty for any individual aircraft-based mass balance approach experiment was ±38 %. Treating the mass balance experiments, which were repeated seven times within nine days, as individual quantifications of the Balt-Wash CO2 emissions, the estimation uncertainty was ±16 % (standard error of the mean at 95% CL). Our aircraft-based estimate was compared to various bottom-up fossil fuel CO2 (FFCO2) emission inventories. Based on the FLAGG-MD aircraft observations, we estimate 1.9±0.3 MtC of FFCO2 from the Balt-Wash area during the month of February 2015. The mean estimate of FFCO2 from the four bottom-up models was 2.2±0.3 MtC.

Abstract A41: Cancer-associated fibroblast (CAF) specific biomarkers in pancreatic ductal adenocarcinoma (PDAC): Transcriptomic and molecular insight

Pancreatic ductal adenocarcinoma (PDAC) is one of malignancy-related death with poor prognosis. The late diagnosis due to nonspecific symptoms, highly aggressive nature, intrinsic resistance to chemotherapeutic, and the lack of effective therapeutic are the main causes of poor prognosis in PDAC. This cancer type comprises up to 90% cellular component of desmoplastic stroma that holds a major role in drug resistance and malignancy. The complexity of the genome is another leading cause of molecular alteration in PDAC. Hence, the urge to find the prognosis marker for PDAC is extremely needed for the new therapeutic regimens. In this study we performed RNA-seq analysis from MSC in single and co-cultured conditions (in vitro), MSC and Xeno-MSC (in vivo), and patient-derived CAF. Read alignment and junction mapping was accomplished using HISAT2 and cufflinks respectively and followed by map reads using UCSC hg38 reference genome annotation. Data were expressed as fragments per kilobase of exon per million fragments mapped (FPKM). Three out of eight clusters on heatmap were selected based on their expression pattern across all the samples. Approximately 900 transcripts from selected clusters were classified into three major protein classes: transcription factors, kinases, and membrane proteins. Remarkably, several genes on selected clusters have been studied in CAF, giving proof of the fidelity of our data analysis. Prompted to get more specific CAF-related genes, we put more parameters such us: unexpressed in normal pancreatic, relatively low expression in pancreatic cancer, ≥2 folds increase of CAF mRNA expression to normal or pancreatic cancer, and have not studied in PDAC. We found 16 transmembrane protein-coding genes that are potentially involved in CAF remodeling. To gain a better understanding of tumor-CAF interaction from these candidate genes, immunostaining using paraffin sections from tumor-bearing mice model together with αSMA/IL6 and protein analysis was carried out. We sought the downstream pathways as well to discover novel regulatory networks and causal relationship between CAF and pancreatic cancer. Our study addresses the extent to which factor(s) can reset stromal alteration and elucidate the role of transmembrane protein during CAF reprogramming.

Citation Format: Jayarani F. Putri, Yutaro Kumagai, Yoshihiro Miyazaki, T. Oda, Yasuyuki S. Kida. Cancer-associated fibroblast (CAF) specific biomarkers in pancreatic ductal adenocarcinoma (PDAC): Transcriptomic and molecular insight [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer: Advances in Science and Clinical Care; 2019 Sept 6-9; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2019;79(24 Suppl):Abstract nr A41.

Association of the PCK2 Gene Polymorphism With New-onset Glucose Intolerance in Japanese Kidney Transplant Recipients

BACKGROUND

New-onset diabetes mellitus after transplantation (NODAT) is a risk factor for both cardiovascular disease and poor graft survival after kidney transplantation (KTx). In this study, we identified single-nucleotide polymorphisms (SNPs) in genes involved in glucose metabolism and examined the correlation between these SNPs and glucose intolerance after KTx.

METHODS

Thirty-eight patients with normal glucose tolerance before KTx were included in this study. Patients with plasma glucose levels of >140 mg/dL at 120 minutes on the 75-g oral glucose tolerance test at 1 year after KTx were classified as having new-onset impaired glucose tolerance (NIGT). We identified 8 SNPs in 7 genes that are involved in glucose metabolism among the patients included in this study, and compared the prevalence rate of NIGT among SNPs in each gene.

RESULTS

Of the 38 patients, 11 (28.9%) were diagnosed with NIGT. For rs4982856 in the PCK2 gene, the distribution of genotypes among the total patient population was as follows: T/T, 12 (31.6%); T/C, 22 (57.9%); and C/C, 4 (10.5%). Seven of 11 patients with NIGT had the T/T genotype of rs4982856, whereas only 5 of 27 patients with normal glucose tolerance had this genotype. The T allele frequency of the rs4982856 was significantly higher in the NIGT group than in the normal group (81.8 vs 52.8%, respectively; P = .015).

CONCLUSION

Our study indicates that the T allele of the rs4982856 SNP in the PCK2 gene may be a risk factor for glucose intolerance after KTx.

Polη, a Y-family translesion synthesis polymerase, promotes cellular tolerance of Myc-induced replication stress

Growth of precancerous and cancer cells relies on their tolerance of oncogene-induced replication stress (RS). Translesion synthesis (TLS) plays an essential role in the cellular tolerance of various types of RS and bypasses replication barriers by employing specialized polymerases. However, limited information is available about the role of TLS polymerases in oncogene-induced RS. Here, we report that Polη, a Y-family TLS polymerase, promotes cellular tolerance of Myc-induced RS. Polη was recruited to Myc-induced RS sites, and Polη depletion enhanced the Myc-induced slowing and stalling of replication forks and the subsequent generation of double-strand breaks (DSBs). Overexpression of a catalytically dead Polη also promoted Myc-induced DSB formation. In the absence of Polη, Myc-induced DSB formation depended on MUS81-EME2 (the S-phase-specific endonuclease complex), and concomitant depletion of MUS81-EME2 and Polη enhanced RS and cell death in a synergistic manner. Collectively, these results indicate that Polη facilitates fork progression during Myc-induced RS, thereby helping cells tolerate the resultant deleterious effects. Additionally, the present study highlights the possibility of a synthetic sickness or lethality between Polη and MUS81-EME2 in cells experiencing Myc-induced RS.

Association between OGG1 S326C CC genotype and elevated relapse risk in acute myeloid leukemia

Recent studies have shown that tumors of relapsed acute myeloid leukemia (AML) present additional genetic mutations compared to the primary tumors. The base excision repair (BER) pathway corrects oxidatively damaged mutagenic bases and plays an important role in maintaining genetic stability. The purpose of the present study was to investigate the relationship between BER functional polymorphisms and AML relapse. We focused on five major polymorphisms: OGG1 S326C, MUTYH Q324H, APE1 D148E, XRCC1 R194W, and XRCC1 R399Q. Ninety-four adults with AML who achieved first complete remission were recruited. Genotyping was performed with the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The OGG1 S326C CC genotype (associated with lower OGG1 activity) was observed more frequently in patients with AML relapse [28.9 vs. 8.9%, odds ratio (OR) = 4.10, 95% confidence interval (CI) = 1.35-12.70, P = 0.01]. Patients with the CC genotype exhibited shorter relapse-free survival (RFS). Moreover, the TCGA database suggested that low OGG1 expression in AML cells is associated with a higher frequency of mutations. The present findings suggest that the OGG1 S326C polymorphism increased the probability of AML relapse and may be useful as a prognostic factor for AML relapse risk.

Impact of an infectious disease specialist on antifungal use: an interrupted time-series analysis in a tertiary hospital in Tokyo

BACKGROUND

Antimicrobial stewardship programmes are considered essential for optimizing antimicrobial use in order to improve patient outcomes, reduce the number of adverse sequelae, prevent resistance, and ensure cost-effective therapy.

AIM

To assess the efficacy and the limitations of antifungal antimicrobial stewardship programmes.

METHODS

A bundle to manage infectious diseases was implemented in our hospital in October 2010. Data regarding antimicrobial use density (AUD) from April 2006 to May 2016 were collected. Trends in AUD were assessed using an interrupted time-series model for three separate periods: the pre-bundle, the bundle implementation, and the long-term follow-up periods. The primary and secondary outcomes were AUD (defined daily dose (DDD) per 1000 patient-days) of intravenous antifungals and expenditure on antifungals per fiscal year, respectively.

FINDINGS

The AUD for all intravenous antifungals decreased from 26.1 in 2006 to 9.9 in 2015. Whereas the change in the trend during the pre-bundle period was not significant (slope: 0.062; 95% confidence interval (CI): -0.180 to 0.305), a significant decrease was observed in the bundle implementation period (slope: -0.535; 95% CI: -0.907 to -0.164). The trend slowed during the long-term follow-up period (slope: -0.040; 95% CI: -0.218 to 0.138). Total expenditure on antifungals decreased by 73%, from ¥52,354,411 in fiscal year 2006 to ¥14,073,099 in fiscal year 2015.

CONCLUSION

The bundle significantly reduced the use of antifungals and decreased costs over time, but this effect was limited in that it had stabilized within three years.

Acute HSF1 depletion induces cellular senescence through the MDM2-p53-p21 pathway in human diploid fibroblasts

Heat shock transcription factor 1 (HSF1) regulates the expression of a wide array of genes, control of the expression of heat shock proteins (HSPs) and cell growth. Although acute depletion of HSF1 induces cellular senescence, the underlying mechanisms are poorly understood. Here, we report that HSF1 depletion-induced senescence (HDIS) of human diploid fibroblasts (HDFs) was independent of HSP-mediated proteostasis but dependent on activation of the p53-p21 pathway, partly because of the increased expression of dehydrogenase/reductase 2 (DHRS2), a putative MDM2 inhibitor. We observed that HDIS occurred without decreased levels of major HSPs or increased proteotoxic stress in HDFs. Additionally, an inhibitor of HSP70 family proteins increased proteotoxicity and suppressed cell growth, but failed to induce senescence. Importantly, we found that activation of the p53-p21 pathway due to reduced MDM2-dependent p53 degradation was required for HDIS. Furthermore, we provide evidence that increased DHRS2 expression contributes to p53 stabilization and HDIS. Collectively, our observations uncovered a molecular pathway in which HSF1 depletion-induced DHRS2 expression leads to activation of the MDM2-p53-p21 pathway required for HDIS.

Hypoxia-Inducible Factor-1α Expression in Kidney Transplant Biopsy Specimens After Reperfusion Is Associated With Early Recovery of Graft Function After Cadaveric Kidney Transplantation

BACKGROUND

Ischemia/reperfusion injury during kidney transplantation (KTx) delays allograft recovery. Hypoxia-inducible factor-1α (HIF-1α) is the key regulator of the protective response to ischemia/reperfusion injury. We evaluated the impact of the HIF-1α signaling pathway on allograft recovery during cadaveric KTx.

METHODS

Between 1996 and 2015, 46 patients underwent cadaveric KTx. The expression levels of HIF-1α-related proteins, including phosphoinositide 3-kinase, phosphorylated (p)-Akt, p-mammalian target of rapamycin, p-Eukaryotic translation initiation factor 4E, p-S6 ribosomal protein, and HIF-1α, were immunohistochemically evaluated and semi-quantitatively scored in graft biopsy specimens after 1 hour of revascularization. Ten kidney biopsy specimens collected during donor nephrectomy for living KTx were used as controls. Delayed graft function (DGF) was defined as the need for dialysis within 1 week of KTx. We compared the staining scores of each protein and several clinical parameters between patients with and those without DGF.

RESULTS

Expression levels of all six proteins in specimens after revasculization were elevated compared with those in controls. Thirty-five patients had DGF. Expression levels of PI3K, p-AKT, p-mTOR, p-eIF4E, and HIF-1α were significantly higher in patients without DGF than in those with DGF. Univariate analysis identified expression levels of p-Akt, p-S6, and HIF-1α, in addition to donor type (heart beating/non-heart beating), cold ischemic time, and donor age as significant predictors of DGF. Of these, only expression levels of HIF-1α and donor type were independently associated with DGF in multivariate analysis.

CONCLUSIONS

Up-regulation of HIF-1α in allografts after reperfusion may be a predictor of early recovery after cadaveric KTx.

A decadal inversion of CO2 using the Global Eulerian-Lagrangian Coupled Atmospheric model (GELCA): sensitivity to the ground-based observation network

We present an assimilation system for atmospheric carbon dioxide (CO₂) using a Global Eulerian-Lagrangian Coupled Atmospheric model (GELCA), and demonstrate its capability to capture the observed atmospheric CO₂ mixing ratios and to estimate CO₂ fluxes. With the efficient data handling scheme in GELCA, our system assimilates non-smoothed CO₂ data from observational data products such as the Observation Package (ObsPack) data products as constraints on surface fluxes. We conducted sensitivity tests to examine the impact of the site selections and the prior uncertainty settings of observation on the inversion results. For these sensitivity tests, we made five different site/data selections from the ObsPack product. In all cases, the time series of the global net CO₂ flux to the atmosphere stayed close to values calculated from the growth rate of the observed global mean atmospheric CO₂ mixing ratio. At regional scales, estimated seasonal CO₂ fluxes were altered, depending on the CO₂ data selected for assimilation. Uncertainty reductions (URs) were determined at the regional scale and compared among cases. As measures of the model-data mismatch, we used the model-data bias, root-mean-square error, and the linear correlation. For most observation sites, the model-data mismatch was reasonably small. Regarding regional flux estimates, tropical Asia was one of the regions that showed a significant impact from the observation network settings. We found that the surface fluxes in tropical Asia were the most sensitive to the use of aircraft measurements over the Pacific, and the seasonal cycle agreed better with the results of bottom-up studies when the aircraft measurements were assimilated. These results confirm the importance of these aircraft observations, especially for constraining surface fluxes in the tropics.

DS02R1: Improvements to Atomic Bomb Survivors' Input Data and Implementation of Dosimetry System 2002 (DS02) and Resulting Changes in Estimated Doses

Individual dose estimates calculated by Dosimetry System 2002 (DS02) for the Life Span Study (LSS) of atomic bomb survivors are based on input data that specify location and shielding at the time of the bombing (ATB). A multi-year effort to improve information on survivors' locations ATB has recently been completed, along with comprehensive improvements in their terrain shielding input data and several improvements to computational algorithms used in combination with DS02 at RERF. Improvements began with a thorough review and prioritization of original questionnaire data on location and shielding that were taken from survivors or their proxies in the period 1949-1963. Related source documents varied in level of detail, from relatively simple lists to carefully-constructed technical drawings of structural and other shielding and surrounding neighborhoods. Systematic errors were reduced in this work by restoring the original precision of map coordinates that had been truncated due to limitations in early data processing equipment and by correcting distortions in the old (WWII-era) maps originally used to specify survivors' positions, among other improvements. Distortion errors were corrected by aligning the old maps and neighborhood drawings to orthophotographic mosaics of the cities that were newly constructed from pre-bombing aerial photographs. Random errors that were reduced included simple transcription errors and mistakes in identifying survivors' locations on the old maps. Terrain shielding input data that had been originally estimated for limited groups of survivors using older methods and data sources were completely re-estimated for all survivors using new digital terrain elevation data. Improvements to algorithms included a fix to an error in the DS02 code for coupling house and terrain shielding, a correction for elevation at the survivor's location in calculating angles to the horizon used for terrain shielding input, an improved method for truncating high dose estimates to 4 Gy to reduce the effect of dose error, and improved methods for calculating averaged shielding transmission factors that are used to calculate doses for survivors without detailed shielding input data. Input data changes are summarized and described here in some detail, along with the resulting changes in dose estimates and a simple description of changes in risk estimates for solid cancer mortality. This and future RERF publications will refer to the new dose estimates described herein as "DS02R1 doses."

Regulatory T-cells Infiltrate Periodontal Disease Tissues

CD4+CD25+ regulatory T (Tr) cells are critical in regulating the immune response and thereby play an important role in the defense against infection and control of autoimmune diseases. Our previous studies demonstrated the involvement of autoimmune responses in periodontitis. The aim of this study was to identify CD4+CD25+ Tr cells in periodontitis tissues and compare them with those in gingivitis tissues. Immunohistological analysis of CD4, CD25, and CTLA-4 and the gene expression analysis of FOXP3, TGF-β1, and IL-10 on gingival biopsies revealed the presence of CD4+CD25+ Tr cells in all tissues. In periodontitis, the percentage of CD4+CD25+ Tr cells increased with increasing proportions of B-cells relative to T-cells. FOXP3, a characteristic marker for CD4+CD25+ Tr cells, TGF-β1 and IL-10 were expressed more highly in periodontitis compared with gingivitis. These findings suggest that CD4+CD25+ Tr cells and possibly other regulatory T-cell populations do exist and may play regulatory roles in periodontal diseases.

Pulsed neutron time-dependent intensity modulation for quasi-elastic neutron scattering spectroscopy

We propose a basic formula and demonstration for a high-resolution quasi-elastic neutron scattering (QENS) by combining the time-of-flight (TOF) method with Modulation of Intensity by Zero Effort (MIEZE) type neutron spin echo spectroscopy. The MIEZE technique has the potential to develop a unique approach to study on slow dynamics of condensed matter; however, the energy resolution is limited owing to the hypersensitivity of the MIEZE signal contrast to the echo condition, which is strongly affected by the alignment of the instruments and the sample. The narrow allowance of the optimal alignment is a major obstacle to the wide use of this technique. Combining the TOF method with MIEZE (TOF-MIEZE), the hypersensitivity of MIEZE signals is significantly alleviated with a short pulsed beam. This robustness is very useful to optimize experimental alignments and enables accurate measurements of QENS. The experimental results demonstrate the characteristic of the TOF-MIEZE technique and are well described by the formula presented in this study.

Long-term detection of seasonal influenza RNA in faeces and intestine

Some cases of seasonal influenza virus (human influenza A virus (IAV)/human influenza B virus (IBV)) are associated with abdominal symptoms. Although virus RNA has been detected in faeces, intestinal infection has not been clearly demonstrated. We aimed to provide evidence that IAV/IBV infects the human intestine. This prospective observational study measured virus RNA in faecal and sputum samples from 22 patients infected with IAV/IBV (19 IAV positive and three IBV positive). Nineteen patients were included in the analysis and were assigned to faecal IAV-positive and -negative groups. Virus kinetics were examined in faecal samples from an IAV-infected patient (patient 1) and an IBV-infected patient (patient 2). Finally, intestinal tissue from an IAV-diagnosed patient who developed haemorrhagic colitis and underwent colonoscopy was examined for the presence of replicating IAV (patient 3). Virus RNA was detected in faecal samples from 8/22 IAV/IBV-infected patients (36.4%). Diarrhoea occurred significantly more often in the faecal IAV-positive group (p 0.002). In patients 1 and 2, virus RNA became undetectable in sputum on days 7 and 10 after infection, respectively, but was detected in faeces for a further 2 weeks. Virus mRNA and antigens were detected in intestinal tissues (mucosal epithelium of the sigmoid colon) from patient 3. These findings suggest that IAV/IBV infects within the intestinal tract; thus, the human intestine may be an additional target organ for IAV/IBV infection.

Usefulness of Alginate Lyases Derived from Marine Organisms for the Preparation of Alginate Oligomers with Various Bioactivities

Alginate-degrading enzyme, alginate lyase, catalyzes the cleavage of glycosidic 1-4 O-linkages between uronic acid residues of alginate by a β-elimination reaction leaving a 4-deoxy-l-erythro-hex-4-ene pyranosyluronate as nonreducing terminal end. The enzymes from a wide variety of sources such as marine molluscs, seaweeds, and marine bacteria have been discovered and studied not only from a point of view of enzymological interest of enzyme itself but also for elucidation of fine chemical structure of alginate, structure-activity relationship of alginate, and biological activities and physicochemical features of the enzymatic digestion products. Based on the substrate specificities, alginate lyases are classified into three groups: poly(β-d-mannuronate) lyase, poly(α-l-guluronate) lyase, and bifunctional alginate lyase, which are specific to mannuronate, guluronate, and both uronic acid residues, respectively. We have studied enzymological aspects of these three types of alginate lyases, and bioactivities of enzymatically digested alginate oligomers. In this chapter, we described the purification and characterization of three types of alginate lyases from different marine origins and overviewed the bioactivities of alginate oligomers.

Candida Soluble Cell Wall β-D-Glucan Induces Lung Inflammation in Mice

Bioactivity of cell wall component(s) of fungi has not been fully elucidated, especially in vivo. We isolated Candida soluble beta-D-glucan (CSBG) from Candida albicans (C. albicans). We investigated the effects of airway exposure to CSBG on the immune systems in the airways in mice. CSBG exposure induced neutrophilic and eosinophilic inflammation in the lung, which was concomitant with the increased local expression of proinflammatory cytokines including tumor necrosis factor - α, interleukin (IL)-1 β, IL-6, macrophage inflammatory protein -1 α, macrophage chemoattractant protein -1, RANTES (regulated on activation and normal T cells expressed and secreted), and eotaxin. The lung inflammation with enhanced expression of proinflammatory proteins caused by CSBG was directly related to its structure, since structurally degraded products of CSBG by formic acid induced negligible responses in the lung. CSBG enhanced nuclear localization of phosphorylated signal transducer and activator of transcription (STAT)-6 in the lung. These results suggest that airway exposure to CSBG induces lung inflammation, at least partly, via the enhanced expression of proinflammatory cytokines and the activation of STAT-6 pathway, and can be a proper murine model for fungal lung inflammation.

A case of ovarian small cell carcinoma of the pulmonary type that was observed as it developed

INTRODUCTION

In the case reported here, the authors observed ovarian small cell carcinoma of the pulmonary type as it developed.

CASE

The patient was a 48-year-old woman who underwent a hysterectomy for CIN3 in 2007. A year later, the woman underwent screening for ovarian cancer. A gradually growing ovarian mass was noted. This mass was found to be a mixed tumor. This mixed tumor grew to 36 mm in size, and six months later it had enlarged to 119 mm. After surgery, the tumor was pathologically diagnosed as an ovarian small cell carcinoma of the pulmonary type with a neuroendocrine nature that was positive for CD56 and synaptophysin. Postoperatively, the patient received six courses of combined therapy with irinotecan and cisplatin (CPT-P therapy), and the patient has survived disease- free for over two years.

CONCLUSION

Findings suggested that ovarian small cell carcinoma of the pulmonary type is a type I ovarian malignancy that develops through an adenoma-carcinoma sequence.

Positive association of free triiodothyronine with pancreatic β-cell function in people with prediabetes

AIM

To analyse the effects of thyroid hormones on β-cell function and glucose metabolism in people with prediabetes who are euthyroid.

METHODS

A total of 111 people who were euthyroid underwent 75-g oral glucose tolerance tests, of whom 52 were assigned to the normal glucose tolerance and 59 to the prediabetes groups. Homeostatic model assessment of β-cell function, insulinogenic index and areas under the curve for insulin and glucose were evaluated as indices of pancreatic β-cell function.

RESULTS

In both groups, BMI, fasting insulin, homeostasis model assessment ratio and HDL cholesterol correlated significantly with all indices of pancreatic β-cell function. Free triiodothyronine correlated positively with all insulin secretion indices in the prediabetes group. Multiple linear regression analysis showed that free triiodothyronine was an independent variable that had a positive correlation with all indices of β-cell function in the prediabetes group. By contrast, no such correlation was found in the normal glucose tolerance group.

CONCLUSIONS

Free triiodothyronine is associated with both basal and glucose-stimulated insulin secretion in people with prediabetes who are euthyroid; therefore, the regulation of insulin secretion by thyroid hormones is a potentially novel therapeutic target for the treatment of diabetes.

Mallet fingers with bone avulsion and DIP joint subluxation

One-third of all mallet fingers are associated with a fracture. Mallet fractures associated with large fracture fragments may result in volar subluxation of the distal phalanx. The management of mallet fractures varies based on injury pattern and surgeon preference. These treatment options include splinting regimens, closed reduction and percutaneous pinning and open reduction and internal fixation. Although numerous surgical techniques have been described, there is little clear consensus on operative treatment. Moreover, there is insufficient evidence to support operative over nonoperative treatment for mallet fractures.