Comparison of patient-reported outcomes and clinical characteristics among patients with pituitary macroadenomas and giant adenomas

KEY POINTS

Patients with giant adenomas are more likely to have tumor extension into the paranasal sinuses. Compared to macroadenomas, giant adenomas are not associated with worse preoperative SNOT-22 scores.

Clinical and technical factors in endoscopic skull base surgery associated with reconstructive success

BACKGROUND

In this study, we identified key discrete clinical and technical factors that may correlate with primary reconstructive success in endoscopic skull base surgery (ESBS).

METHODS

ESBS cases with intraoperative cerebrospinal fluid (CSF) leaks at four tertiary academic rhinology programs were retrospectively reviewed. Logistic regression identified factors associated with surgical outcomes by defect subsite (anterior cranial fossa [ACF], suprasellar [SS], purely sellar, posterior cranial fossa [PCF]).

RESULTS

Of 706 patients (50.4% female), 61.9% had pituitary adenomas, 73.4% had sellar or SS defects, and 20.5% had high-flow intraoperative CSF leaks. The postoperative CSF leak rate was 7.8%. Larger defect size predicted ACF postoperative leaks; use of rigid reconstruction and older age protected against sellar postoperative leaks; and use of dural sealants compared to fibrin glue protected against PCF postoperative leaks. SS postoperative leaks occurred less frequently with the use of dural onlay. Body-mass index, intraoperative CSF leak flow rate, and the use of lumbar drain were not significantly associated with postoperative CSF leak. Meningitis was associated with larger tumors in ACF defects, nondissolvable nasal packing in SS defects, and high-flow intraoperative leaks in PCF defects. Sinus infections were more common in sellar defects with synthetic grafts and nondissolvable nasal packing.

CONCLUSIONS

Depending on defect subsite, reconstructive success following ESBS may be influenced by factors, such as age, defect size, and the use of rigid reconstruction, dural onlay, and tissue sealants.

Metastatic secondary gliosarcoma: patient series

BACKGROUND

Gliosarcoma is a rare and highly malignant cancer of the central nervous system with the ability to metastasize. Secondary gliosarcoma, or the evolution of a spindle cell-predominant tumor after the diagnosis of a World Health Organization grade IV glioblastoma, has also been shown to metastasize. There is little information on metastatic secondary gliosarcoma.

OBSERVATIONS

The authors present a series of 7 patients with previously diagnosed glioblastoma presenting with recurrent tumor and associated metastases with repeat tissue diagnosis consistent with gliosarcoma. The authors describe the clinical, imaging, and pathological characteristics in addition to carrying out a systematic review on metastases in secondary gliosarcoma.

LESSONS

The present institutional series and the systematic review of the literature show that metastatic secondary gliosarcoma is a highly aggressive disease with a poor prognosis.

P06.07.A Natural killer cells lyse glioblastoma stem cells and increase their sensitivity to chemotherapy

Background

Glioblastoma is the most common and lethal brain tumor in the adult population and immunotherapy is playing an increasingly central role in the treatment of many cancers. Nevertheless, the search for effective immunotherapeutic approaches for glioblastoma patients continues. In this study, we aimed to explore the therapeutic potential of allogeneic highly activated super-charged natural killer (NK) cells in glioblastoma.

Material and Methods

Chromium release- and calcein release-based cytotoxicity assays, ELISA, ELISPOT, and multiplex cytokine assays were used to determine NK cell cytotoxicity against glioblastoma stem cells (GSCs) and secretion of cytokines. Cell surface marker expression using flow cytometry and cell growth in vitro and in vivo were measured to determine GSC phenotype. NK cell killing and penetration in 3D were measured using confocal microscopy of GSC tumorospheres.

Results

Super-charged NK cells efficiently lysed patient-derived GSCs in 2D and 3D models potentially reversing the immunosuppression observed in patients. NK-cells secreted IFN-γ, upregulated GSC surface expression of CD54 and MHC class I and increased sensitivity of GSCs to chemotherapeutic drugs. Co-localization of NK cells with GBM cells in perivascular niches in glioblastoma tissues and their direct contact with GSCs in tumorospheres suggests their ability to infiltrate glioblastoma tumors and target GSCs.

Conclusion

Allogeneic super-charged NK cells appear to be a potential therapeutic approach for glioblastoma by selectively killing therapy-resistant cancer stem cell population, increasing their immune-related surface markers and enhancing their sensitivity to chemotherapy. Due to GSC heterogeneity and plasticity personalized immunotherapeutic strategies should be developed to effectively target glioblastomas.

Secretory pathway Ca2+-ATPase SPCA2 regulates mitochondrial respiration and DNA damage response through store-independent calcium entry

A complex interplay between the extracellular space, cytoplasm and individual organelles modulates Ca2+ signaling to impact all aspects of cell fate and function. In recent years, the molecular machinery linking endoplasmic reticulum stores to plasma membrane Ca2+ entry has been defined. However, the mechanism and pathophysiological relevance of store-independent modes of Ca2+ entry remain poorly understood. Here, we describe how the secretory pathway Ca2+-ATPase SPCA2 promotes cell cycle progression and survival by activating store-independent Ca2+ entry through plasma membrane Orai1 channels in mammary epithelial cells. Silencing SPCA2 expression or briefly removing extracellular Ca2+ increased mitochondrial ROS production, DNA damage and activation of the ATM/ATR-p53 axis leading to G0/G1 phase cell cycle arrest and apoptosis. Consistent with these findings, SPCA2 knockdown confers redox stress and chemosensitivity to DNA damaging agents. Unexpectedly, SPCA2-mediated Ca2+ entry into mitochondria is required for optimal cellular respiration and the generation of mitochondrial membrane potential. In hormone receptor positive (ER+/PR+) breast cancer subtypes, SPCA2 levels are high and correlate with poor survival prognosis. We suggest that elevated SPCA2 expression could drive pro-survival and chemotherapy resistance in cancer cells, and drugs that target store-independent Ca2+ entry pathways may have therapeutic potential in treating cancer.

The endosomal pH regulator NHE9 is a driver of stemness in glioblastoma

A small population of self-renewing stem cells initiate tumors and maintain therapeutic resistance in glioblastoma (GBM). Given the limited treatment options and dismal prognosis for this disease, there is urgent need to identify drivers of stem cells that could be druggable targets. Previous work showed that the endosomal pH regulator NHE9 is upregulated in GBM and correlates with worse survival prognosis. Here, we probed for aberrant signaling pathways in patient-derived GBM cells and found that NHE9 increases cell surface expression and phosphorylation of multiple receptor tyrosine kinases (RTKs) by promoting their escape from lysosomal degradation. Downstream of NHE9-mediated receptor activation, oncogenic signaling pathways converged on the JAK2-STAT3 transduction axis to induce pluripotency genes Oct4 and Nanog and suppress markers of glial differentiation. We used both genetic and chemical approaches to query the role of endosomal pH in GBM phenotypes. Loss-of-function mutations in NHE9 that failed to alkalinize endosomal lumen did not increase self-renewal capacity of gliomaspheres in vitro. However, monensin, a chemical mimetic of Na+/H+ exchanger activity, and the H+ pump inhibitor bafilomycin bypassed NHE9 to directly alkalinize the endosomal lumen resulting in stabilization of RTKs and induction of Oct4 and Nanog. Using orthotopic models of primary GBM cells we found that NHE9 increased tumor initiation in vivo. We propose that NHE9 initiates inside-out signaling from the endosomal lumen, distinct from the established effects of cytosolic and extracellular pH on tumorigenesis. Endosomal pH may be an attractive therapeutic target that diminishes stemness in GBM, agnostic of specific receptor subtype.

Abstract 1125: Secretory pathway calcium ATPase-2 (SPCA2) regulates metastasis by suppressing mesenchymal markers in triple negative breast cancer cell lines

Introduction: Over 90% of cancer deaths in breast cancer are associated with metastasis. Epithelial-mesenchymal transition (EMT) is the hallmark of metastasis. Dysregulation of the Ca2+ toolkit has profound consequences for tumor growth and metastasis, raising hopes for novel avenues of therapeutic intervention. The Secretory Pathway Ca2+-ATPase Isoform 2 (SPCA2) transports Ca2+ from cytoplasm to the Golgi, and elicits Ca2+ influx by interacting with plasma membrane Ca2+ channels. Previously, we showed that SPCA2 is implicated in breast cancer progression (Feng et al., Cell 2010). Furthermore, low SPCA2 expression is associated with triple negative breast cancers (TNBC), which are highly metastatic. Therefore, we investigated if ectopic expression of SPCA2 modulates EMT in TNBC cell lines.

Methods: TCGA invasive breast carcinoma project datasets were accessed through cBioPortal. Gene expression was determined by qPCR and protein expression by Immunoblotting and confocal microscopy. Live cell calcium imaging was performed using Fura-2 AM dye. NSG mice were used for in vivo studies.

Results: Low SPCA2 expression was associated with poor survival in TNBC patients (n=255, P < 0.05). TNBC cell lines show low SPCA2 expression compared to receptor positive cell lines, when normalized to non-tumorigenic epithelial cell line MCF-10A. Similarly, significantly low SPCA2 expression (P < 0.001) was observed in TNBC patients compared to receptor positive subtypes. Interestingly, we did not observe these results in SPCA1, the housekeeping SPCA isoform, revealing isoform-specific function of Golgi calcium pumps in breast cancer subtypes. Ectopic expression of SPCA2 in TNBC cell line MDA-MB-231 significantly increased baseline intracellular Ca2+ levels (P < 0.001) and uptake of extracellular Ca2+ (P < 0.001) through store independent calcium entry. Increased SPCA2 expression suppressed mesenchymal gene markers (CDH2, SNAI1, SNAI2, VIM and ZEB1, P < 0.05), and decreased cell migration in vitro (P < 0.05) in TNBC cell lines. Overexpression of SPCA2 in MDA-MB-231-luc-D3H2LN cell line reduced metastasis in vivo (quantified 5-weeks after injection in mammary fat pad, P < 0.01) (n=6) compared to control group. Treatment of metastatic TNBC patients with histone deacetylase (HDAC) inhibitors is currently being evaluated in clinical trials. We found treatment of TNBC cell lines with FDA-approved HDAC inhibitors vorinostat and romidepsin elevated SPCA2 expression in a dose-dependent manner (P < 0.05), simultaneously decreasing mesenchymal gene expression (P < 0.05).

Conclusion: These novel findings point to a causal link between low SPCA2 levels, poor prognosis, and the epithelial-mesenchymal transition required for breast cancer metastasis. Restoration of SPCA2 expression in TNBC by HDAC inhibitors may have therapeutic potential.

Citation Format: Monish Ram Makena, Donna K. Dang, Myungjun Ko, Manuj Bandral, Rajini Rao. Secretory pathway calcium ATPase-2 (SPCA2) regulates metastasis by suppressing mesenchymal markers in triple negative breast cancer cell lines [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1125.

A Ca2+-ATPase Regulates E-cadherin Biogenesis and Epithelial-Mesenchymal Transition in Breast Cancer Cells

Progression of benign tumors to invasive, metastatic cancer is accompanied by the epithelial-to-mesenchymal transition (EMT), characterized by loss of the cell-adhesion protein E-cadherin. Although silencing mutations and transcriptional repression of the E-cadherin gene have been widely studied, not much is known about posttranslational regulation of E-cadherin in tumors. We show that E-cadherin is tightly coexpressed with the secretory pathway Ca²⁺-ATPase isoform 2, SPCA2 (ATP2C2), in breast tumors. Loss of SPCA2 impairs surface expression of E-cadherin and elicits mesenchymal gene expression through disruption of cell adhesion in tumorspheres and downstream Hippo-YAP signaling. Conversely, ectopic expression of SPCA2 in triple-negative breast cancer elevates baseline Ca²⁺ and YAP phosphorylation, enhances posttranslational expression of E-cadherin, and suppresses mesenchymal gene expression. Thus, loss of SPCA2 phenocopies loss of E-cadherin in the Hippo signaling pathway and EMT-MET transitions, consistent with a functional role for SPCA2 in E-cadherin biogenesis. Furthermore, we show that SPCA2 suppresses invasive phenotypes, including cell migration in vitro and tumor metastasis in vivo. Based on these findings, we propose that SPCA2 functions as a key regulator of EMT and may be a potential therapeutic target for treatment of metastatic cancer. IMPLICATIONS: Posttranslational control of E-cadherin and the Hippo pathway by calcium signaling regulates EMT in breast cancer cells.

Protective effect of a brown algae, Sargassum horneri on particulate matter-induced oxidative stress and inflammation in MLE-12 cells

The constant exposure to fine particulate matter (PM) induces oxidative stress and proinflammatory cytokine production. The ROS formed by oxidative stress is related to activate NF-κB signal pathway for inflammation. Sargassum horneri, a brown algae found in East Asia, is known to be an excellent source for bioactive components. In this study, the antioxidant and anti-inflammation effects of Sargassum horneri ethanol extract (SHE) on the PM-induced oxidative stress in MLE-12, a type II alveolar epithelial cell line were investigated. As the exposure concentration of PM increased to 1,000 μg/mL, the cell viability was reduced; however, it was increased when treated with SHE. The ROS generation and lipid peroxidation of MLE-12 cells were increased from the PM concentration of 125 μg/mL and they were reduced after treatment of SHE at 62.5 and 125 μg/mL. The expressions of antioxidant enzymes, catalase (CAT) and superoxide dismutase (SOD2), in MLE-12 cells exposed to PM were lower than those exposed to PM with SHE. The PM was proved to increase the expression of 8-OHdG, one of DNA oxidative damage markers, and OGG1, the repair enzyme of 8-OHdG, while SHE protected the DNA damage of cell. The expression of NF-κB signaling was reduced by SHE. These results suggest that SHE can adjust the expression of antioxidant enzymes, help to suppress the oxidative stress induced by PM, and attenuate its oxidative damage and NF-κB pathway to lung epithelial cells by eliminating over-produced ROS.

This research is part of a project titled ‘Development of functional food products with natural materials derived from marine resources’ funded by the Ministry of Oceans and Fisheries, Republic of Korea in 2017 (Project NO. 20172085).

Presence of the Paternal Pronucleus Assists Embryo in Overcoming Cycloheximide Induced Abnormalities in Zygotic Mitosis

After fertilization, the maternal and paternal chromosomes independently proceed through pronuclear formation. These chromatin reconfigurations occur within a shared cytoplasm thus exposing both gametes to the same factors. Here, we report that continuous cycloheximide [40 μg/mL] treatment of parthenogenotes, androgenotes, and ICSI embryos reveals ORC2 pronuclear instability in the maternal (MPN) but not the paternal pronucleus (PPN). When released from CHX after 8 h, the MPN can recover ORC2 and proceed through replication, however, parthenogenotes encounter severe mitotic defects while both ICSI embryos and androgenotes are able to recover and develop at significantly higher rates. Taken together, these data suggest cycloheximide treatment promotes an environment that asymmetrically affects the stability of ORC2 on the MPN, and the ability of the MPN to develop. Furthermore, the presence of the PPN in the zygote can ameliorate both effects. These data suggest further evidence for crosstalk between the two pronuclei during the first cell cycle of the embryo. J. Cell. Biochem. 117: 1806-1812, 2016. © 2016 Wiley Periodicals, Inc.

ORC4 surrounds extruded chromatin in female meiosis

Six proteins, ORC1-6, make up the origin recognition complex (ORC) that initiates licensing of DNA replication origins. We have previously reported that subunit ORC2 is localized between the separating maternal chromosomes at anaphase II just after fertilization and is present in zygotic pronuclei at G1. Here, we found that ORC1, 3, and 5 all localize between the chromosomes at anaphase II, but could not be detected in zygotic G1. ORC6 localized to the periphery of the nucleoli at all zygotic stages. We identified an unexpected potential role for ORC4 in polar body formation. We found that in both female meiotic divisions, ORC4 surrounds the set of chromosomes, as a sphere-like structure, that will eventually be discarded in the polar bodies, but not the chromosomes that segregate into the oocyte. None of the other five ORC proteins are involved in this structure. In Zygotic G1, ORC4 surrounds the nuclei of the polar bodies, but was not detectable in the pronuclei. When the zygote entered mitosis ORC4 was only detected in the polar body. However, ORC4 appeared on both sets of separating chromosomes at telophase. At this point, the ORC4 that was in the polar body also migrated into the nuclei, suggesting that ORC4 or an associated protein is modified during the first embryonic cell cycle to allow it to bind DNA. Our results suggest that ORC4 may help identify the chromosomes that are destined to be expelled in the polar body, and may play a role in polar body extrusion. ORC4 surrounds the chromatin that will be extruded in the polar body in both female meiotic divisions, then makes a transition from the cytoplasm to the chromosomes at zygotic anaphase, suggesting multiple roles for this replication licensing protein.

First Report of the Powdery Mildews Leveillula taurica and Podosphaera pannosa on Rose Periwinkle in the United States

In April 2013, unthrifty rose periwinkle (Catharanthus roseus (L.) G. Don) from a residential garden in Mililani, HI, was sent to the Hawaii Department of Agriculture. Symptoms, present on all plants, included leaf chlorosis, defoliation, and premature flower drop with necrotic spots on the adaxial side of leaves corresponding to patches of grayish mildew-like growth on the abaxial side. Samples were collected and sent to USDA PPQ National Identification Services (NIS) for confirmation. At NIS, stereoscope examination of the plants revealed two distinct powdery mildews. One, on the stems and leaves, had dimorphic conidia, with lanceolate primary (54 to 72 × 14 to 22 μm) and cylindrical secondary conidia (49 to 75 × 11 to 21 μm) (n = 25 for each), both with a reticulate surface. This fungus was identified morphologically as Leveillula taurica (Lév.) G. Arnaud (1). The second powdery mildew appeared confined to the sepals and petals. The external hyphae of this fungus produced upright chains of cylindrical to ovoid conidia (up to eight per chain), which contained fibrosin bodies and measured 22 × 12 μm (n = 50) with straight foot cells averaging 43 μm long, placing this fungus in the genus Podosphaera Kunze (1). Plants containing both fungi were accessioned as BPI892677 in the US National Fungal Collection. For molecular characterization, genomic DNA of the Podosphaera was obtained by scraping conidia from a petal and extracting with Thermo Scientific's Lyse and Go PCR Reagent. DNA of the Leveillula was extracted from 5 mm² of infected leaf using Qiagen's Plant mini kit. The ITS region of each fungus was amplified and sequenced directly with primers ITS1F and ITS4. Each consensus sequence was created from manually edited chromatograms, searched against NCBI's GenBank using MegaBLAST and phylogenetically analyzed in MEGA5.2 under maximum parsimony (MP) in context with most similar hits and representatives from phylogenetic studies (2,3). Sequences from types of these fungi are not available for comparison. The resulting Podosphaera phylogeny grouped the Podosphaera suspect (GenBank KF703448) within a clade of P. pannosa (e.g., AB525938; bootstrap = 90). The Leveillula phylogeny grouped the Leveillula suspect (KF703447) within a clade (bootstrap = 88) of L. taurica (e.g., AB044346), L. chrozophorae (AB044346), and L. elaeagni (AB048350). Although the ITS sequences of these taxa are phylogenetically indistinguishable, morphological characters differentiate each species and the suspect as L. taurica (1). L. taurica has been recorded on C. roseus in India and Korea (1). This is the first report of L. taurica on C. roseus in the United States. This is the first report of P. pannosa on C. roseus worldwide. P. pannosa is commonly known as a powdery mildew of Rosaceae hosts, and has also been reported on hosts in the Anacardaciae and Oleaceae (1). P. pannosa represents the second Podosphaera species reported on any member of the Apocynaceae, with P. sparsa reported on other Apocynaceae genera (1). The presence of two powdery mildew genera on different parts of the same plant could cause multiple forms of damage and impact the production of this popular landscape ornamental plant. References: (1) U. Braun and R. T. A. Cook. Taxonomic Manual of the Erysiphales (Powdery Mildews), CBS Biodiversity Series No. 11. CBS, Utrecht, Netherlands, 2012. (2) S. A. Khodoparast et al. Mycol. Res. 105:909, 2001. (3) S. Takamatsu et al. Persoonia 24:38, 2010.

First Report of Rust Caused by Pucciniastrum boehmeriae on Māmaki (Pipturus albidus) in Hawaii

Pipturus albidus (Hook. & Arn.) A. Gray or māmaki is a flowering plant species in the Urticaceae (nettles) endemic to the Hawaiian Islands. Māmaki is a forest and agricultural commodity, as well as a traditional medicinal and fiber crop. In August 2013, leaf rust was observed in Kuristown, Hawaii, on 15 māmaki plants. Infected leaves had vein-delimited chlorotic spots on the adaxial surface and yellow to orange uredinia on the abaxial surface. Uredinia were scattered, minute, pulverulent, subepidermal, and dome-shaped with a central pore, consistent with Pucciniastrum. Urediniospores were 16 to 23 × 10 to 14 μm, echinulate, ellipsoid to pyriform, walls hyaline, 0.5 μm thick, contents pale yellow to bright yellow. No teliospores were observed. A voucher specimen was deposited in the U.S. National Fungus Collections (BPI 892695). The only species of Pucciniastrum previously known on Pipturus, Pucciniastrum pipturi Syd. [syn. Uredo pipturi (Syd.) Hirats. f.], has larger urediniospores, 26.5 to 40.0 × 19.5 to 27.5 μm, and is currently reported from Japan and the Philippines (3). The pathogen was identified as Pucciniastrum boehmeriae (Dietel) Syd. & P. Syd., which infects Boehmeria Jacq., also in the Urticaceae, and has urediniospores that are 18 to 27 × 13 to 18 μm and similar in shape (2). DNA was extracted from uredinial lesions and the nuclear ribosomal internal transcribed spacer (ITS2) region and the 5' end of large subunit (28S) rDNA were amplified and sequenced following the protocol of Aime (1). The resulting fragment (GenBank Accession No. KF711854) was 100% identical to authenticated and vouchered P. boehmeriae ITS2/28S rDNA sequences (AB221449 to AB221451 and AB221391 to AB221393) (4). Sequences from P. pipturi are not available for comparison, but host family, molecular, and morphological data support the identification of the rust as P. boehmeriae, which is found throughout eastern Asia. To our knowledge, this is the first report of P. boehmeriae on māmaki and the first report in Hawaii on any host. Plant health professionals and regulatory officials can utilize this information to establish survey methods and implement appropriate management practices for this rust disease. References: (1) M. C. Aime. Mycoscience 47:112, 2006. (2) N. Hiratsuka. Revision of Taxonomy of the Pucciniastreae. Kasai Publishing and Printing, Tokyo, 1958. (3) M. Kakishima and T. Kobayashi. Mycoscience 35:125, 1994. (4) Y.-M. Liang et al. Mycoscience 47:137, 2006.

Increased expression of TRPC4 channels associated with erectile dysfunction in diabetes

In recent reports, an association between altered TRPC channel function and the development of various diabetic complications has drawn the attention of many investigators. The aim of this study was to investigate the expression of TRPC4 channels of corpus smooth muscle (CSM) cells in diabetes, and to evaluate the association between erectile dysfunction (ED) and altered TRPC4 channel function. The expression of TRPC4 in the penile tissue of human, normal and diabetic rat was investigated using RT-PCR, western blotting and immunohistochemistry (IHC). In vivo gene transfer of dominant negative (DN) TRPC4 into the CSM of rat was conducted. In vivo pelvic nerve stimulation was performed to measure erectile function. Expression of TRPC1, TRPC3, TRPC4 and TRPC6 in human and rat CSM tissues was confirmed by RT-PCR, western blot and IHC. In the diabetic rat, the expression levels of mRNA and protein of the TRPC4, and TRPC6 were significantly increased compared to control rats (p < 0.05). The change in TRPC4 expression in the diabetic rats was higher than those of the other TRPC subunits (p < 0.05). The IHC showed that only TRPC4 expression had a higher intensity in the diabetes compared to normal rats (p < 0.05). Gene transfection with TRPC4(DN) into the diabetic rats restored erectile function to levels similar to that of normal controls. Gene expression of TRPC4(DN) in CSM tissue was confirmed by RT-PCR 2 weeks after transfection. This study demonstrated that TRPC4 channel expression increased in the penile CSM cells of diabetic rats. The down-regulation of TRPC4 with DN form restored erectile function in the diabetic rats. The alteration of TRPC4 channel is one of pathophysiology of ED and could be a target for drug development for ED.

First Report in Hawai'i of Xanthomonas citri pv. mangiferaeindicae Causing Bacterial Black Spot on Mangifera indica

Bacterial black spot of mango (Mangifera indica) caused by Xanthomonas citri pv. mangiferaeindicae (Xcm), is an economically important disease in tropical and subtropical areas (3). Xcm can infect a wide range of mango cultivars and induces raised, angular, black leaf lesions, sometimes with a chlorotic halo. Fruit symptoms appear as small, water-soaked spots on the lenticels that become star-shaped, erumpent, and exude an infectious gum (3). The bacterium can also cause latent infections (2). Immature mango fruit with black spots on the epidermis were collected in August 2012 from mango trees of the cvs. Raposa and Pirie at a residence in Pukalani, Hawai'i, on the island of Maui. Similar symptoms were seen on a tree of the mango cv. Common (also known as 'Spanish' or 'Lahaina') at a nearby golf course. Mango fruit with black lesions, and leaves showing black lesions with yellow halos, were collected in August 2012 from mango trees of the cv. Haden at a residence in Kaimuki, Hawai'i, on the island of O'ahu. Xanthomonas-like bacterial colonies were isolated on TZC agar. Suspect colonies were non-pigmented on YDC agar. A fruit strain of the bacterium from Maui (A6081A) and a strain from each of a fruit (A6081B) and a leaf (A6082) from O'ahu were each gram-negative, oxidative, positive for both starch and esculin hydrolysis, and negative for nitrate reduction, resulting in presumptive identification as a Xanthomonas sp. The three strains were further characterized by Microlog (Biolog, Inc. Hayward, CA), which showed the closest match with X. campestris. In addition, 16S rDNA PCR assays showed the closest match (99% similarity) with X. citri strains, and RIF marker analysis of dnaA (4) grouped the three strains with Xcm strain LMG 941 (Accession No. CAHO01000002.1). Hypersensitivity responses typical of xanthomonads were observed when these strains were infiltrated into tobacco leaves, whereas no response was observed using sterile water. Leaves of 3-week-old mango seedlings were infiltrated using 10 μl (~10⁸ CFU/ml) of each strain suspended in sterilized water (six to eight inoculations per leaf, four leaves per plant, and three replicate plants per strain). The negative control treatments consisted of inoculation with sterile water, as well as an incompatible pathogen, X. hortorum pv. vitians (A6076), isolated from lettuce. Typical symptoms of bacterial black spot were observed for all strains assayed approximately 2 weeks after inoculation. No lesions were observed on the negative control plants. Koch's postulates were satisfied following reisolation and identification of the Xanthomonas strains from the infected plant tissues, using the biochemical and PCR methods described above. Results for strains from the two islands confirmed published descriptions of the pathogen, indicating that the pathogen causing symptoms on these mango trees is Xcm (1). Cultures and infected plant samples were sent to USDA APHIS and CPHST NPGLB facilities where this identification was confirmed. To our knowledge, this is the first report of bacterial black spot of mango in Hawai'i or anywhere in the United States. It is unknown whether this disease is a new occurrence or has not been reported previously. The origin of the primary inoculum is unknown. References: (1) B. Manicom and F. Wallis. Int. J. Syst. Bacteriol. 34:77, 1984. (2) O. Pruvost et al. Microbial Ecol. 58:928. (3) O. Pruvost et al. Plant Dis. 95:774, 2011. (4) K. Schneider et al. PLoS 6:e18496, 2011.

Chronic osteomyelitis secondary to human bite: a case report

ABSTRACT

We report a case of a human bite that was initially inadequately treated and progressed to chronic osteomyelitis, finally resulting in digital amputation. Human bites are seemingly innocuous, but if neglected, may lead to subsequent infection and morbidity. Persistence of symptoms should alert the practitioner to the possibility of infection extending to the soft tissue or bone. Bacteriological studies commonly yield mixed aerobic and anaerobic flora. Early debridement and antibiotic treatment may prevent development of severe soft tissue or bone infection.

KEY WORDS

human bite, osteomyelitis, amputation.

Effect of dry matter intake on visceral organ mass, cellularity, and the protein expression of ATP synthase, Na+/K+-ATPase, proliferating cell nuclear antigen and ubiquitin in feedlot steers

Twenty-four steers [467 ± 7.2 kg initial body weight (BW)] predominately of Angus breeding were used to determine the effect of dry matter intake (1.25, 1.50, 1.75, and 2.00% of BW) on visceral mass, cellularity, and the protein expression of ATP synthase, Na+/K+-ATPase, proliferating cell nuclear antigen (PCNA) and ubiquitin. There were linear increases (P ≤ 0.05) in weights of total viscera, total digestive tract, liver, kidney, heart, lung, spleen, rumen, and abomasum with increasing dry matter intake (DMI). Protein concentration decreased linearly (P < 0.05) in small intestinal mucosa as DMI increased. PCNA expression increased linearly (P < 0.01) in liver as DMI increased. PCNA expression was affected quadratically (P < 0.05) in pancreas and small intestinal mucosa with an increase when DMI increased from 1.25 to 1.75% of BW, and a decrease when DMI increased from 1.75 to 2% of BW. ATP synthase, Na+/K+-ATPase, and ubiquitin expression in pancreas and ubiquitin expression in small intestinal mucosa increased linearly (P < 0.05) as DMI increased. These results indicate that increasing DMI increases the mass of visceral organs and carcass and influences expression of proteins influencing energy utilization and efficiency in pancreas, small intestine, liver, and sternomandibularis muscle.Key words: Dry matter intake, visceral organ mass, cellular energy metabolism, steer

Elucidating genetic events in human hepatocellular carcinoma

e15590

Background: Hepatocellular carcinoma (HCC) is prevalent world wide with increasing incidence in North America. 4q is a commonly deleted region in HCC and is lost in 32% of premalignant cirrhotic nodules but the precise molecular lesion involved in tumor initiation remains unknown. Human Plk4, a member of the polo family of cell cycle regulating serine /threonine kinases is located on 4q28. Plk4 is a haploinsufficient tumor suppressor in mice, with 50% of animals developing spontaneous tumors, most commonly multifocal primary HCC. We hypothesize that Plk4 plays a role in the initiation of human HCC. Our purpose was to determine the levels of Plk4 in human HCC and investigate possible genetic interactions with the tumor suppressor p53. Methods: Formalin-fixed paraffin-embedded sections of human HCCs, adjacent non-neoplastic liver tissue and gallbladder tissue were microdissected. DNA was extracted and manual LOH analysis was performed. To asses Plk4 expression, RNA from the hepatoma cases was used for real time RT-PCR. To elucidate a genetic interaction, Plk4 p53 compound mutant mice were generated and murine embryonic fibroblasts (MEFs) were derived and cultured. Results: In HCC Plk4 LOH rates varied from 57% for the marker closest to Plk4 to 8% for the marker furthest away (n=32). Using an intragenic marker the rate of LOH was 45% (n=24). Studies in CRC (n=46) and pancreas cancer specimens (n=40) showed only background levels of LOH. Expression of Plk4 in HCC tumor samples that displayed LOH at the Plk4 locus was reduced compared to non-neoplastic liver. Plk4±p53−/− mice showed acceleration of tumor formation compared to Plk4+/+p53−/− mice. Plk4±p53−/− MEFs had increased levels multinucleation, centrosome amplification and aneuploidy compared to Plk4+/+p53−/− cells. In addition these cells were tumorigenic in vivo whereas Plk4+/+p53−/− cells were not. Conclusions: Our results demonstrate significant rates of LOH at the Plk4 locus specifically in human HCC and indicate that this is associated with decreased Plk4 expression. In addition, our studies of compound mutant mice suggest a possible genetic interaction of Plk4 and p53 in tumor development.

No significant financial relationships to disclose.

Mechanisms of Plk4 haploinsufficiency in hepatocellular carcinogenesis

11100

Background: The pathogenesis of hepatocellular carcinoma (HCC) is multifactorial and includes genetic predisposition, though the precise nature of the latter is as yet poorly understood. Mice heterozygous for the polo like kinase Plk4 develop spontaneous HCC and human HCC cases show a high rate of LOH (loss of heterozygosity) at the Plk4 locus. We hypothesize that Plk4 is a haploinsufficient tumor suppressor in man. The purpose of this study was to investigate the mechanisms by which a 50% reduction of Plk4 leads to carcinogenesis. Methods: We established Plk4± and Plk4+/+ murine embryonic fibroblast cell lines (MEFs) in vitro. 5 of 5 Plk4+/+ MEF lines senesced at passage 7–8 as expected, while 9 of 9 Plk4±MEF lines immortalized in culture under NIH 3T3 protocol. The latter were used at passage 15–20 for in vivo tumorigenesis studies. Results: Plk4± MEFs demonstrated increased ploidy with increased passage number. By passage 4, Plk4± MEFs showed a near tetraploid karyotype as well as multiple chromosomal rearrangements and deletions, as assessed by Spectral Karyotype (SKY) Analysis. 5 out of 9 late passage Plk4± MEF lines injected into NOD-SCID mice grew tumors, with a latency of 3 to 12 weeks. By contrast, injection of Plk4+/+ MEFs yielded no tumors. Tumors generated from injection of Plk4± MEFs were harvested, cultured and submitted to SKY analysis; this showed increased clonal rearrangements and deletions compared to the parent cell lines. Conclusion: A 50% reduction in Plk4 expression results in immortalization, aneuploidy and chromosomal instability in vitro, and tumorigenicity in vivo. These results demonstrate that insufficient levels of Plk4, whether due to mutation or LOH, can contribute to the pathogenesis of HCC.

No significant financial relationships to disclose.

Correlation between kinetic features on breast MRI computer-aided detection (CAD) and prognostic factors of breast cancer

Abstract #4015

The purpose of this study was to correlate the kinetic features of breast MR computer-aided detection (CAD) with the prognostic factors of breast cancer.&#x2028; A total of 65 patients were included in our study from December 2007 to March 2008. We reviewed kinetic features of MR CAD such as proportion of initial rapid rise enhancement, percentage of washout, and enhancement patterns. We also recorded prognostic factors such as tumor size, estrogen receptor, progesterone receptor, HER-2/neu status, lymphovascular invasion, and histologic grade on pathology. We correlated the kinetic features on MR CAD with prognostic factors. Pearson and Spearman correlation test were used to evaluate correlation between kinetic features and tumor size. Fisher exact test also used for the statistical analysis between kinetic features and other prognostic factors.&#x2028; In 65 cases, 59 cases showed rapid washout enhancement patterns, 5 cases showed rapid plateau pattern and only one case showed medium plateau. Tumor size showed correlation with the initial rapid rise enhancement (p=0.03) on Pearson correlation test and the delayed washout percentage (p=0.05) on Spearman correlation test.&#x2028; Positive progesterone receptor status was significantly associated with rapid early enhancement (p=0.023) and delayed washout (p=0.05), respectively. HER-2/neu status showed trend with the early enhancement (p=0.063). Other prognostic factors such as estrogen receptor, lymphovascular invasion and histologic grade showed no significant correlation with the kinetic features on MR CAD.&#x2028; Several kinetic features on MR CAD were correlated with the specific prognostic factors of breast cancer. Recognition of several kinetic features correlated with prognostic factors might help to predict of patients' prognosis and to decide the treatment plan.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 4015.

Pancreatic mass, cellularity, and α-amylase and trypsin activity in feedlot steers fed increasing amounts of a high-moisture-corn based diet

Twenty-four yearling beef steers (initial BW = 467 ± 3.6 kg), predominately of Angus breeding, were used in a randomized complete block design to determine the effect of dietary intake on pancreatic cellularity, mass, and α-amylase and trypsin activity. Steers were individually fed a high-moisture corn-based diet at 1.25, 1.50, 1.75, and 2.00% of BW (DM basis) using Calan gates. After 28 d on treatment, the heaviest steer from each dietary treatment was slaughtered per wk and pancreata collected. Average daily gain (kg) and pancreatic weight (g) increased linearly (P ≤ 0.01) with increasing DM intake. Pancreatic DNA and RNA concentration and content, and RNA:DNA and protein:DNA did not differ (P > 0.05) between treatments. This suggests that the observed increase in tissue weight was due to increases in both cell size and number. Total pancreatic α-amylase activity (kU pancreas-1) increased linearly (P = 0.04) with increasing DM intake. These data indicate that total pancreatic α-amylase activity (kU pancreas-1) linearly increases with increasing intake of a high-moisture corn-based finishing diet and that dietary intake-dependent changes in total pancreatic α-amylase activity are primarily due to changes in pancreatic weight rather than changes in the concentration of pancreatic α-amylase activity (U g-1 pancreas). Key words: Beef cattle, pancreas, α-amylase, trypsin, feed intake

Corn or soybean hull incorporation into haylage-based backgrounding beef cattle diets: Effect on growth and efficiency during the backgrounding and finishing periods

This experiment was conducted to evaluate the effects of corn or soybean hull incorporation into haylage-based diets on backgrounding calf performance and subsequent feedlot performance. Crossbred steers [n = 48, initial body weight (BW) = 303 ± 3.4 kg] were individually fed dietary treatments consisting of: (1) haylage [17.5% crude protein, dry matter (DM) basis; control], (2) haylage + 20% (DM basis) cracked corn, and (3) haylage + 20% (DM basis) soybean hulls during a 112-d backgrounding period. After the backgrounding period, all steers were adapted to a common high moisture corn-based finishing diet and fed until an ultrasound estimated backfat thickness of 7 mm was obtained. During the backgrounding period, steers fed cracked corn or soybean hulls had greater (P < 0.01) average daily gain, dry matter intake and gain:feed and lower (P = 0.05) plasma urea N as compared with controls. However, when finished on a common high-concentrate diet, steers previously fed cracked corn had greater (P < 0.08) average daily gain, final body weight, and longissimus muscle area than those fed soybean hulls, suggesting that source of supplemental energy during the backgrounding period may influence subsequent feedlot performance. Key words: Beef cattle, backgrounding, energy supplementation

Neoplastic transformation in vitro by low doses of ionizing radiation: role of adaptive response and bystander effects

The shape of the dose-response curve for cancer induction by low doses of ionizing radiation is of critical importance to the assessment of cancer risk at such doses. Epidemiologic analyses are limited by sensitivity to doses typically greater than 50-100 mGy for low LET radiation. Laboratory studies allow for the examination of lower doses using cancer-relevant endpoints. One such endpoint is neoplastic transformation in vitro. It is known that this endpoint is responsive to both adaptive response and bystander effects. The relative balance of these processes is likely to play an important role in determining the shape of the dose-response curve at low doses. A factor that may influence this balance is cell density at time of irradiation. The findings reported in this paper indicate that the transformation suppressive effect of low doses previously seen following irradiation of sub-confluent cultures, and attributed to an adaptive response, is reduced for irradiated confluent cultures. However, even under these conditions designed to optimize the role of bystander effects the data do not fit a linear no-threshold model and are still consistent with the notion of a threshold dose for neoplastic transformation in vitro by low LET radiation.

Neoplastic transformation in vitro induced by low doses of 232 MeV protons

The aim was to define the dose--response curve for high-energy proton-induced neoplastic transformation in vitro. The HeLa x skin fibroblast human hybrid cell assay was used to determine the frequency of neoplastic transformation following doses of 232 MeV protons (mean linear energy transfer, LET=0.44 keV microm(-1)) in the range 5-600 mGy. Proton irradiations were carried out at the Loma Linda University Proton Treatment Facility, CA, USA. The data indicate no evidence for induction of transformation below a dose of 100 mGy. At doses of 5 and 50 mGy, there is evidence for a possible suppression of transformation frequencies below that for spontaneous transformation. The shape of the dose--response curve for high-energy proton-induced transformation of the human hybrid cell line CGL1 does not follow a linear no-threshold model and shows evidence for a threshold as well as for possible suppression of transformation at doses <100 mGy, similar to that seen for other low-LET radiations.

Traumatic anterior dislocation of the hip associated with ipsilateral femoral shaft fracture in a child: a case report

Traumatic anterior dislocation of the hip joint in children is rare, and only one case with ipsilateral femoral fracture has been reported in Japan. We report a case of such dislocation and a review of the literature. The patient was a 31-month-old girl who was injured in a car accident while asleep on a tilted front passenger seat. Radiographic examination showed dislocation of the right obturator foramen and transverse fracture of the ipsilateral femoral shaft. The dislocation of the right hip was easily reduced without anaesthesia during radiography. We applied Bryant traction after reduction for 4 weeks, followed by cast application for 3 weeks. Walking with support and full weightbearing were permitted 14 weeks and 16 weeks after the injury, respectively. Radiography at 4.5 years after the injury showed a mildly enlarged right femoral head and femur overgrowth of approximately 8 mm. Magnetic resonance imaging showed no evidence of suspected avascular necrosis of the femoral head. The patient has no subjective or objective symptoms, and is able to engage in all usual activities. The detailed mechanism of the injury is unknown. We assume that the lower leg was dislocated through abduction during flexion, or abducent, external flexion, considering that the child was sleeping at the time of the accident. Since she was hurled to the back seat, it was assumed that strong external force was vertically added to the femur, which caused the abducent force.

Vascular surgery training in general surgery residency programs: the Canadian experience

OBJECTIVES

Vascular surgery is traditionally considered a component of general surgery. There is growing evidence of improved patient outcome related to surgeon volume and vascular certification status. The American Board of Surgery in the United States, as well as until recently the Royal College of Physicians and Surgeons in Canada, requires that vascular surgery be considered an essential content area of general surgery training. This requirement is controversial. The purpose of this study was to describe experience and perceived competence in common vascular surgery procedures during general surgery residency training in Canada.

METHODS

This web-based survey was conducted between January and June 2002. General surgery program directors (GSPDs), vascular surgeons involved in general surgery training programs (VSs), and senior general surgery residents (SRs) from the 13 English-speaking general surgery programs in Canada were surveyed. Questions were asked regarding which vascular surgery procedures are appropriate for general surgeons to perform, which procedures SRs are trained to perform, and which procedures SR intend to perform.

RESULTS

The response rate was 62% for GSPDs, 57% for VSs, and 45% for SRs. Overall, 49% of SRs did not intend to perform any vascular procedures after training. GSPDs, VSs, and SRs indicated that most SRs should be and are trained to perform varicose vein surgery, leg amputation, and femoral embolectomy (P >.05). In addition, GSPDs, VSs, and SRs indicated that SRs should not be and are not trained to perform infrainguinal bypass grafting, carotid endarterectomy, or abdominal aortic aneurysm (AAA) repair (P >.05). There were significant differences with respect to ruptured AAA repair: 49% of SRs, 25% of PDs, and only 12% of VSs believe that general surgeons should be trained to perform ruptured AAA repair (P <.05). Overall, 76% of VSs believe SRs receive too little vascular training.

CONCLUSION

There is similarity between GSPDs, VSs, and SRs with respect to vascular surgery training in Canadian general surgery programs. Vascular surgery training cannot be considered a component of general surgery. More rotations or fellowship training is required to become competent in management of common vascular surgery procedures. Perhaps this level of competence should not be an objective of general surgery training.