MCL1 inhibition: a promising approach to augment the efficacy of sorafenib in NSCLC through ferroptosis induction

Ferroptosis, an iron-dependent form of regulated cell death, plays a crucial role in modulating the therapeutic response in non-small cell lung cancer (NSCLC) patients. Studies have identified the signal transducer and activator of transcription 3 (STAT3) and myeloid cell leukemia-1 (MCL1) as potential targets for sorafenib, which exhibits activities in inducing ferroptosis. However, the role of STAT3-MCL1 axis in sorafenib-induced ferroptosis in NSCLC is still unclear. This study provided evidence that ferroptosis is a critical driver of sorafenib-induced cell death in NSCLC, supported by the accumulation of lipid peroxidation products, indicative of oxidative stress-induced cell death. Additionally, both in vitro and in vivo experiments showed that ferroptosis contributed to a significant portion of the anti-cancer effects elicited by sorafenib in NSCLC. The noticeable accumulation of lipid peroxidation products in sorafenib-treated mice underscored the significance of ferroptosis as a contributing factor to the therapeutic response of sorafenib in NSCLC. Furthermore, we identified the involvement of the STAT3/MCL1 axis in sorafenib-induced antitumor activity in NSCLC. Mechanistically, sorafenib inhibited endogenous STAT3 activation and downregulated MCL1 protein expression, consequently unleashing the ferroptosis driver BECN1 from the BECN1-MCL1 complex. Conversely, there is an augmented association of BECN1 with the catalytic subunit of system Xc-, SLC7A11, whose activity to import cystine and alleviate lipid peroxidation is hindered upon its binding with BECN1. Notably, we found that MCL1 upregulation correlated with ferroptosis resistance in NSCLC upon sorafenib treatment. Our findings highlight the importance of sorafenib-triggered ferroptosis in NSCLC and offer a novel strategy to treat advanced NSCLC patients: by downregulating MCL1 and, in turn, predispose NSCLC cells to ferroptosis.

Comparison of Humoral Antibody Responses and Seroconversion Rates between Two Homologous ChAdOx1 nCoV-19 and mRNA-1273 Vaccination in Patients Undergoing Maintenance Hemodialysis

BACKGROUND

Hemodialysis patients are at an increased risk of SARS-CoV-2 infection and are excluded from preauthorization COVID-19 vaccine trials; therefore, their immunogenicity is uncertain.

METHODS

To compare the antibody responses to homologous ChAdOx1 and mRNA-1273 SARS-CoV-2 vaccination in hemodialysis patients, 103 age- and sex-matched hemodialysis patients with two homologous prime-boost vaccinations were recruited to detect anti-receptor-binding domain (RBD) IgG levels and seroconversion rates (SCRs) 14 days after a prime dose (PD14), before and 28 days after a boost dose (pre-BD0 and BD28).

RESULTS

Both mRNA-1273 and ChAdOx1 vaccinations elicited immunogenicity in study subjects, and the former induced higher anti-RBD IgG levels than the latter. The SCRs of both groups increased over time and varied widely from 1.82% to 97.92%, and were significantly different at PD14 and pre-BD0 regardless of different thresholds. At BD28, the SCRs of the ChAdOx1 group and the mRNA-1273 group were comparable using a threshold ≥ 7.1 BAU/mL (93.96% vs. 97.92%) and a threshold ≥ 17 BAU/mL (92.73% vs. 97.92%), respectively, but they were significantly different using a threshold ≥ 20.2% of convalescent serum anti-RBD levels (52.73% vs. 95.83%). The seroconversion (≥20.2% of convalescent level) at BD28 was associated with mRNA-1273 vaccination after being adjusted for age, sex, body mass index, and the presence of solicited reactogenicity after a prime vaccination.

CONCLUSION

Our prospective, observational cohort indicates that a full prime-boost mRNA-1273 vaccination is likely to provide higher immune protection in hemodialysis patients compared to ChAdOx1, and this population with a prime-boost ChAdOx1 vaccination should be prioritized for a third dose.

Targeting pathogenic macrophages by the application of SHP-1 agonists reduces inflammation and alleviates pulmonary fibrosis

Idiopathic pulmonary fibrosis is a progressive fibrotic disorder with no cure that is characterized by deterioration of lung function. Current FDA-approved drugs for IPF delay the decline in lung function, but neither reverse fibrosis nor significantly improve overall survival. SHP-1 deficiency results in hyperactive alveolar macrophages accumulating in the lung, which contribute to the induction of pulmonary fibrosis. Herein, we investigated whether employing a SHP-1 agonist ameliorates pulmonary fibrosis in a bleomycin-induced pulmonary fibrosis murine model. Histological examination and micro-computed tomography images showed that SHP-1 agonist treatment alleviates bleomycin-induced pulmonary fibrosis. Reduced alveolar hemorrhage, lung inflammation, and collagen deposition, as well as enhanced alveolar space, lung capacity, and improved overall survival were observed in mice administered the SHP-1 agonist. The percentage of macrophages collected from bronchoalveolar lavage fluid and circulating monocytes in bleomycin-instilled mice were also significantly reduced by SHP-1 agonist treatment, suggesting that the SHP-1 agonist may alleviate pulmonary fibrosis by targeting macrophages and reshaping the immunofibrotic niche. In human monocyte-derived macrophages, SHP-1 agonist treatment downregulated CSF1R expression and inactivated STAT3/NFκB signaling, culminating in inhibited macrophage survival and perturbed macrophage polarization. The expression of pro-fibrotic markers (e.g., MRC1, CD200R1, and FN1) by IL4/IL13-induced M2 macrophages that rely on CSF1R signaling for their fate-determination was restricted by SHP-1 agonist treatment. While M2-derived medium promoted the expression of fibroblast-to-myofibroblast transition markers (e.g., ACTA2 and COL3A1), the application of SHP-1 agonist reversed the transition in a dose-dependent manner. Our report indicates that pharmacological activation of SHP-1 ameliorates pulmonary fibrosis via suppression of CSF1R signaling in macrophages, reduction of pathogenic macrophages, and the inhibition of fibroblast-to-myofibroblast transition. Our study thus identifies SHP-1 as a druggable target for the treatment of IPF, and suggests that the SHP-1 agonist may be developed as an anti-pulmonary fibrosis medication that both suppresses inflammation and restrains fibroblast-to-myofibroblast transition.

Evaluating the biological effectiveness of boron neutron capture therapy by using microfluidics-based pancreatic tumor spheroids

Background: The recent success of boron neutron capture therapy (BNCT) for cancer treatment has attracted considerable attention. Because irradiated neutrons penetrate deep into solid tumor tissue, BNCT efficacy is strongly influenced by cell pathophysiology in tumors. The tumor microenvironment critically influences tumor pathophysiology, but its effects on BNCT remain unexplored. Methods: We used a pancreatic tumor as a model to develop a high-throughput 3D tumor spheroid platform for evaluating BNCT efficacy under different microenvironment conditions. We expanded our system to serve as a transwell-like device in order to investigate the influence of stromal fibroblasts in the tumor microenvironment. Results: With the use of the proposed microfluidic chip and a laboratory pipette, more than 40 spheroids with controllable diameters (standard deviation <10%) could be cultured on a chip for more than 10 days. The response to BNCT from each spheroid can be monitored in real time. By using pancreatic tumor spheroids of two different diameters, we found that large spheroids, characterized by more hypoxic microenvironments, exhibited lower BNCT susceptibility. The cells in the hypoxic region expressed the HIF1-α signal, which is crucial in many therapeutic resistance signal pathways. In addition, the heterogeneous presence of stemness markers (Oct-4, Sox-2, and CD 44) implied that the underlying BNCT resistance mechanism was sophisticated. In the presence of fibroblasts, we found an association between β-catenin nuclear translocation and BNCT resistance; membrane contacts from fibroblasts were found to be indispensable for translocation activation. Conclusions: In summary, by means of easily accessible microfluidic engineering, we developed tumor spheroids to recapture the pathophysiological characteristics of pancreatic tumors. Our data suggest that hypoxia and fibrosis can reduce BNCT efficacy in pancreatic cancer treatment. Considering the growing requirement for drug screening in personalized medicine, our findings and the developed method are expected to improve the fundamental understanding of BNCT and facilitate broad applications of BNCT in clinical settings.

Premorbid use of selective beta-blockers improves sepsis incidence and course: Human cohort and animal model studies

Introduction

Beta-blockers are widely prescribed to manage hypertension and cardiovascular diseases and have been suggested as an attractive therapy to improve the prognosis of sepsis. Herein, we investigated the potential benefits of premorbid selective beta-blocker use in sepsis with a real-world database and explored the underlying mechanism by in vivo and in vitro experiments.

Methods

A total of 64,070 sepsis patients and 64,070 matched controls who were prescribed at least one anti-hypertensive drug for more than 300 days within 1 year were selected for the nested case-control study. Female C57BL/6 J mice and THP-1 cells stimulated with lipopolysaccharide (LPS) were used for studying systemic responses during sepsis to validate our clinical findings.

Results

The risk of sepsis was lower in current selective beta-blocker users than in non-users (adjusted OR (aOR), 0.842; 95% CI, 0.755-0.939), and in recent users than in non-users (aOR, 0.773; 95% CI, 0.737-0.810). A mean daily dose of ≥0.5 DDD was associated with a lower risk of sepsis (aOR, 0.7; 95% CI, 0.676-0.725). Metoprolol, atenolol, and bisoprolol users had lower risk of sepsis than non-users. In a LPS-induced sepsis mouse model, mice pre-fed with atenolol had significantly reduced mortality. While atenolol had some mild effects on LPS-induced release of inflammatory cytokines in septic mice, it significantly reduced serum soluble PD-L1 levels. Notably, atenolol treatment reversed the negative correlation of sPD-L1 with inflammatory cytokines in septic mice. Moreover, atenolol markedly downregulated the PD-L1 expression on LPS-stimulated THP-1 monocytes/macrophages via targeting ROS-induced NF-κB and STAT3 activation.

Conclusion

Atenolol pretreatment can reduce sepsis mortality in mice, and in vivo and in vitro studies of PD-L1 expression suggest a role for atenolol in the modulation of immune homeostasis. These findings may contribute to the reduced incidence of sepsis in hypertensive patients with premorbid treatment with selective beta-blockers, especially atenolol.

First Report of Pseudomonas cichorii Causing Bacterial vein necrosis on Perilla plants [Perilla frutescens (L.) Britton.] in South Korea

Perilla (Perilla frutescens L.) is the second most important upland crop and the third largest edible oil crop in Korea (Shin and Kim 1994). During a disease survey in Busan, Korea in September 2021, symptoms of vein necrosis were observed in perilla plants, with incidences of approximately 30% and 50% in two fields. Symptoms of spots on the perilla appeared as leaf dryness and spots with water-soaked blotches largely concentrated on the mid-veins of leaves. The lesions were initiated with water-soaked spots on the leaf or stem and gradually turned black or brown. Necrosis was also observed in the stems. A bacterium was isolated on Luria-Bertani (LB) agar from diseased leaf tissues that were surface-disinfected with 70% ethyl alcohol for 3-5 min and then washed with sterile water three times. Three pieces of sterilized leaf tissue (size: 0.5 × 0.5 cm) were mixed with 500 µL sterile water for 30 min, and then the suspension was serially diluted and spread on LB agar. Subsequently, isolates were cultivated on LB agar and King's Medium B agar (KMB) (Schaad et al. 2001), and they were predominantly cream-colored and circular bacterial colonies with undulated margins. The bacterial colonies on KMB displayed fluorescence under 365 nm UV light. The isolates were analyzed with the GEN III MicroPlate (Biolog, Hayward, CA, USA), and all isolates were identified as Pseudomonas cichorii, a devastating plant bacterium that damages a wide range of host plants worldwide, including in South Korea (Hikichi et al. 2013; Ramkumar et al. 2015). To identify the species of the bacterial pathogen, genomic DNA of four isolates (BS4922, BS4167, BS4345, and BS4560) was extracted, and the 16S rRNA gene and hrcRST gene were amplified with universal primers, 27F/1492R and Hcr1/Hcr2, and sequencing was then done (Patel et al. 2019). In the BLAST analysis, the 16S rRNA sequences (GenBank OM060656, OM275434, OM275435, OM275436) showed a 100% and 99% similarity to P. cichorii strains MAFF 302698 (AB724286) and P. cichorii strain Pc-Gd-4 (KU923373), respectively. Further, hrcRST gene sequences (GenBank OM143596, OM268864, OM268865, and OM268866) showed high similarity (>99%) with P. cichorii strain P16-51 (MG518230). A pathogenicity test of the four isolates was performed on 3 - 4 weeks old perilla plants by creating wounds with a needle on the lower leaves and stems, and then the plants were inoculated by spraying inoculum (108 CFU/ml). The plants that served as the negative control were wounded and sprayed with unsterilized water. The inoculated perilla plants were placed in a greenhouse at 28 ± 2oC , 80-85% relative humidity, and a natural photoperiod. The inoculation site began to show symptoms of water-soaked brown lesions. Disease symptoms such as leaf dryness, water-soaked blotches on the mid-vein of leaves, and necrosis on plant stems were observed in the inoculated plants 7-10 days after inoculation, whereas the plants of the negative control group did not show any symptoms. The bacteria were re-isolated from the diseased tissues of the plants, and DNA sequence analysis identified them as P. cichorii. Additionally, all isolates induced hypersensitivity reactions in tobacco and tomato leaves within 24 h after inoculation. To our knowledge, this is the first report of P. cichorii infecting perilla in South Korea. The findings in this study will provide the basic information for the development of diagnostic tools and management measures against P. cichorii in perilla.

Comparative survival analysis of platinum-based adjuvant chemotherapy for early-stage squamous cell carcinoma and adenocarcinoma of the lung

Background and Purpose

Although cytotoxic platinum‐based adjuvant chemotherapy (pACT) has been recommended for patients with completely resected early‐stage (ES) non–small‐cell lung cancer (ES‐NSCLC), therapeutic regimens for NSCLC have evolved in the past two decades. The study was aimed to examine the effectiveness of postoperative pACT for resected ES‐NSCLC patients with squamous cell carcinoma (SCC) or adenocarcinoma (ADC) according to real‐world data.

Methods and Patients

Inverse probability treatment weighting (IPTW) was used to adjust baseline characteristics between the group receiving pACT and those not receiving any treatment (observation, OBS) within 3 months after curative surgery. Cox regression models were used to compare overall survival (OS) and treatment failure‐free survival (TFS) between the groups.

Results

Of 31,208 patients with ES‐NSCLC, 4700 undergoing complete tumor resection were eligible, with a mean follow‐up period of 4.5 years. The pACT (n = 2347) and OBS (n = 2353) groups were well‐balanced after IPTW. The median OS differed between the pACT and OBS groups (77.2 vs. 75.5 months, adjusted hazard ratio [aHR] = 0.87, 95% confidence interval [CI] = 0.79–0.95, p = 0.003), and the 5‐year survival rates were 58.2% and 55.3%, respectively (p < 0.001). In the SCC group, pACT was superior to OBS in OS (75.0 vs. 57.4 months, aHR = 0.74, 95% CI = 0.62–0.88, p = 0.001) and TFS (32.7 vs. 21.8 months, aHR = 0.74, 95% CI = 0.63–0.86, p < 0.001). Both OS and TFS did not differ between two groups in those with ADC.

Conclusion

Real‐world data indicated that pACT confers a survival benefit for resected ES‐NSCLC patients with SCC but not ADC, which needs to be verified by a large sample of randomized controlled studies.

Stabilization of AURKA by the E3 ubiquitin ligase CBLC in lung adenocarcinoma

CBL family proteins (CBL, CBLB and CBLC in mammals) are E3 ubiquitin ligases of protein tyrosine kinases. CBL mediates the lysosomal degradation of activated EGFR through K63-linked ubiquitination, while CBLC has an oncogenic function by positively regulating EGFR activation through K6 and K11-linked ubiquitination in EGFR mutant lung adenocarcinoma (LAD). Here, we used immunoprecipitation and mass spectrometry to study the CBLC interactome, and found that CBLC is also involved in cell cycle regulation by stabilizing Aurora kinase A (AURKA). CBLC interacted with the kinase domain of AURKA and positively regulated the stability of AURKA by conjugating monoubiquitination and K11/K63-linked polyubiquitination, which are protective from degrading K11/K48 polyubiquitination. CBLC depletion markedly decreased the half-life of AURKA in cycloheximide-treated LAD cells. When LAD cells were synchronized with double thymidine block at the G1/S boundary and then released into mitotic arrest, CBLC depletion delayed the accumulation and activation of AURKA and prevented cancer cells from entering mitosis. CBLC deficiency significantly delayed cell cycle progression, reduced the mitotic population, and increased apoptosis of LAD cells. Targeting CBLC inhibited tumor growth of LAD cells and enhanced their sensitivity to paclitaxel in xenograft models. Immunohistochemical staining of the tissue microarray also revealed a positive correlation between the expression of CBLC and AURKA in normal and LAD tissues, further supporting the positive regulation of AURKA expression by CBLC. In summary, these findings indicate that the oncogenic E3 ligase CBLC plays a role in mitotic entry by stabilizing AURKA via ubiquitination in LAD. This work demonstrates that targeting CBLC combined with paclitaxel might be a potential option for the treatment of LAD patients who have no available targeted therapies.

Purely laparoscopic explant hepatectomy and hybrid laparoscopic/robotic graft implantation in living donor liver transplantation

This report describes a purely laparoscopic/robotic technique for successful living donor liver transplantation (LDLT). Purely laparoscopic explant hepatectomy followed by purely laparoscopic and robotic graft implantation can be performed in LDLT.

Alisertib inhibits migration and invasion of EGFR-TKI resistant cells by partially reversing the epithelial-mesenchymal transition

Epithelial growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) have been widely used in the clinical treatment of non-small cell lung cancer (NSCLC) patients with EGFR mutations. Previous studies have shown that Aurora kinase A (AURKA) is overexpressed in a broad spectrum of cancer cells, which can induce epithelial-mesenchymal transition (EMT) and contribute to the occurrence of acquired EGFR-TKI resistance. However, whether the inhibition of AURKA could overcome EGFR-TKI resistance or reverse the EMT in TKI-resistant NSCLC cells remains unclear. In the current study, we established three EGFR-TKI-resistant cell lines and analyzed their expression profiles by RNA sequencing. The results revealed that the EMT pathway is significantly upregulated in the three cell lines with EGFR-TKI resistance. The phosphorylation of AURKA at Thr 288 was also upregulated, suggesting that the activation of AURKA plays an important role in the occurrence of EGFR-TKI resistance. Interestingly, the AURKA inhibitor, alisertib treatment restored the susceptibility of resistant cells to EGFR-TKIs and partially reversed the EMT process, thereby reducing migration and invasion in EGFR-TKI-resistant cells. This study provides evidence that targeting AURKA signaling pathway by alisertib may be a novel approach for overcoming EGFR-TKI resistance and for the treatment of metastatic EGFR-TKIs in NSCLC patients.

Allogeneic human umbilical cord-derived mesenchymal stem cells reduce lipopolysaccharide-induced inflammation and acute lung injury

Acute lung injury (ALI) is the clinical disorder of acute hypoxemic respiratory deficiency and it is associated with a high mortality rate. Increased lung permeability, infiltration of inflammatory cells, secretion of inflammatory cytokines, and pulmonary edema are hallmarks of ALI. Currently, there is no effective pharmacological agent approved for ALI, and the treatment regimens available are mostly supportive. Mesenchymal stem cells (MSCs) are multipotent stromal cells with immunomodulating potential, which therefore hold great promise for the treatment of ALI. We established an LPS-induced ALI mouse model by intratracheal injection of lipopolysaccharide (LPS). Human umbilical cord-derived MSCs (hUC-MSCs) were delivered through the tail vein to assess the effects of MSCs on relieving LPS-induced ALI. Intratracheal injection of LPS increased the infiltration of neutrophils and enhanced the expression of pro-inflammatory cytokines, such as IL-6, IL-1β and TNF-α. Administration of hUC-MSCs decreased pathological signs of inflammation, as well as reduced ALI scores. The levels of IL-6, IL-1β and TNF-α were also dose-dependently inhibited in the bronchoalveolar lavage fluids from damaged lung tissues. Moreover, MPO and BAX levels were decreased by the hUC-MSC treatment, suggesting hUC-MSCs may play the role in inhibiting ROS production and apoptotic death in ALI repair. These results highlight the potential of hUC-MSCs to alleviate bacterial endotoxin-induced inflammation, and may represent an effective modality for the treatment of ALI in clinical settings.

Abstract 4852: CBLC functions as a novel therapeutic target to enhance the efficacy of paclitaxel on EGFR wild-type lung adenocarcinoma by downregulating AURKA

Patients with lung adenocarcinoma harboring driver genes can be treated with target therapies, such as tyrosine kinase inhibitors for epithelial growth factor receptor (EGFR) mutations, anaplastic lymphoma kinase (ALK) inhibitors for ALK gene rearrangements, and so on. However, a large portion of lung adenocarcinoma patients, especially for those with wild-type EGFR, still do not have valid target therapies in clinics. The CBL family proteins (CBL, CBLB, and CBLC) are E3 ubiquitin ligases of protein tyrosine kinases (PTKs), including EGFR, hepatocyte growth factor receptor (MET), and SRC proto-oncogene (SRC). It has been reported that the K63-linkaged ubiquitination mediated by CBL can negatively regulate activated EGFR (aEGFR) signaling through lysosomal degradation. Previously, we discovered that CBLC, unlike CBL, possesses an oncogenic function and positively regulates aEGFR stability through polyubiquitination via K6 and K11 linkages. The CBLC-mediated conjugation of polyubiquitin promotes aEGFR preferentially recycled back to the plasma membrane, or trafficked to the cell nucleus, leading to the sustained activation of EGFR signaling in lung adenocarcinoma. Aside from aEGFR dysregulation, we recently found that CBLC assumes a novel role in positively regulating the expression of Aurora kinase A (AURKA), which contributes to tumor development by promoting cell proliferation, metastasis, epithelial-mesenchymal transition, and drug resistance. In lung adenocarcinoma cells with wild-type EGFR, CBLC knockdown significantly reduced cell viability, delayed cell cycle progression and increased apoptotic death. Our study also showed that CBLC knockdown in EGFR wild type cells was associated with increased sensitivity to paclitaxel, probably through downregulating AURKA. Taken together, these findings indicated that CBLC may play a role in promoting cell cycle progression and may be a novel therapeutic target to enhance the efficacy of paclitaxel on EGFR wild-type lung adenocarcinoma.

Citation Format: Shiao-Ya Hong, Yu-Rung Kao, Yi-Ping Lin, Meng-Hsuan Lee, Jyun-Yi Wu, Cheng-Wen Wu. CBLC functions as a novel therapeutic target to enhance the efficacy of paclitaxel on EGFR wild-type lung adenocarcinoma by downregulating AURKA [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 4852.

Introduction of an Alcohol-Related Electronic Screening and Brief Intervention (eSBI) Program to Reduce Hazardous Alcohol Consumption in Namibia's Antiretroviral Treatment (ART) Program

Alcohol is the most widely abused substance in Namibia and is associated with poor adherence and retention in care among people on antiretroviral therapy (ART). Electronic screening and brief interventions (eSBI) are effective in reducing alcohol consumption in various contexts. We used a mixed methods approach to develop, implement, and evaluate the introduction of an eSBI in two ART clinics in Namibia. Of the 787 participants, 45% reported some alcohol use in the past 12 months and 25% reported hazardous drinking levels. Hazardous drinkers were more likely to be male, separated/widowed/divorced, have a monthly household income > $1000 NAD, and report less than excellent ART adherence. Based on qualitative feedback from participants and providers, ART patients using the eSBI for the first time found it to be a positive and beneficial experience. However, we identified several programmatic considerations that could improve the experience and yield in future implementation studies.

Abstract 4756: Activation of AURKA contributes to TKI resistance in EGFR-mutant non-small lung cancer

The epithelial growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) have been widely used to treat EGFR-mutant non-small cell lung cancer (NSCLC) in clinics. Several generations of TKI were invented to overcome the unfavorable response and acquired resistance after long-term usage of EGFR TKI. Several mechanisms of acquired resistance have been reported. The well-studied resistant mechanism results from EGFR secondary mutations including T790M and C797S, which are involved in the resistance to first and third generation TKI, respectively. Other mechanisms aside from secondary mutation on EGFR including Her2 and MET amplification or epithelial mesenchymal transition (EMT) also distribute to TKI resistance. However, the resistant mechanisms which are independent to these alterations have not been completely identified yet. Here, we generated resistant cells selected by three different generations of TKI and analyzed their gene expression profiles. We discovered that many signal pathways, especially involved in cell cycle regulation, are commonly upregulated in three TKI-resistant cell lines. Aurora kinase A (AURKA) was the upstream kinase of those pathways; however, neither RNA level nor protein level of AURKA was significant changed. Interestingly, we found that phosphorylation of Aurora A at Thr288 in its catalytic domain is higher in TKI resistant cells. This reveals the possibilities that AURKA activation plays a role in the occurrence of TKI-resistance and that TKI-resistant NSCLC patients have a better response rate to AURKA inhibitor treatments.

Citation Format: Meng-Hsuan Lee, Shiao-Ya Hong, Yu-Rung Kao, Cheng-Wen Wu. Activation of AURKA contributes to TKI resistance in EGFR-mutant non-small lung cancer [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 4756.

Identification of subcellular targeting sequences of Cten reveals its role in cell proliferation

Spatial and temporal subcellular localization plays critical roles in regulating protein function. Cten (C-terminal tensin like) is a member of the tensin family. Cten recruits signaling molecules, such as DLC1, to focal adhesions, modulates homeostasis of receptor tyrosine kinases, including EGFR and c-Met, and promotes cell migration. These functions are likely controlled by Cten localization at focal adhesions and/or in the cytoplasm. In addition, Cten has been detected in the nucleus by which mechanism is unknown. To this end, we have examined the distribution of Cten in various cell lines, determined primary sequence requirements for its nuclear and focal adhesion localizations, and analyzed potential roles of nuclear Cten. Our results show that a proportion of Cten translocates to nuclei in cancer cell lines and that nuclear exporting of Cten is a CRM1-dependent process. A nuclear localization sequence and a nuclear export sequence are identified within Cten. In addition, like other tensins, Cten contains two independent focal adhesion binding sites. Although further expression of recombinant Cten showed no effect on cancer cell proliferation, silencing of Cten significantly reduced cell growth. Furthermore, expression of Cten mutants either with defective nuclear export sequence or tagged with SV40 nuclear localization sequence promoted cell growth. These results suggest that nuclear Cten contributes to cancer cell proliferation. Our findings identify a molecular mechanism for regulating Cten protein trafficking in mammalian cells and provide new insights into the dynamics of focal adhesion complexes in health and disease.

Reuse of Living-Donor Liver Graft in Second Recipient with Long-Term Survival

Brain death is a rare situation after living-donor liver transplantation. However, the recipient who suffers from brain death and has functional liver graft is a potential liver donor. We report the 1st case of successful reuse of extended right living-donor liver graft after brain death of the first recipient. The first recipient, who had acute liver failure caused by hepatitis A virus, experienced brain death on the 2nd day after the transplantation. The allograft had a favorable regeneration and functional recovery. On the 7th day, the allograft was procured with a patent hepatic artery, bile duct, portal vein, and reconstructed outflow (right hepatic vein and middle hepatic vein) and successfully implanted into the second recipient. The second recipient has experienced a long-term survival without any complications.

Abstract 2642: CBLC is a potential biomarker for the susceptibility to paclitaxel in lung adenocarcinoma

CBL family proteins have been reported as E3 ubiquitin ligases of receptor tyrosine kinases. CBLC is the most divergent member of CBL family in human due to lack of the distal part of C terminus found in other two proteins, CBL and CBLB. By data mining from TCGA database, CBLC expression was frequently upregulated in lung adenocarcinoma. However, very little is known about the tumorigenic functions of CBLC compared to other CBL family proteins. Although patients with lung adenocarcinoma harboring EGFR mutations can be treated with tyrosine kinase inhibitors (TKIs), there is no good target therapy for treating lung adenocarcinoma patients with EGFR wild-type or TKIs resistance. Here, this study is to investigate if CBLC can be a good target for treatment to benefit these patients. In lung adenocarcinoma cells, CBLC knockdown significantly decreased cell viability, while CBLC overexpression increased the ability to form colonies in soft agar. Flow cytometry analyses revealed that CBLC depletion decreased the cell population of G2/M phase and increased cell apoptosis. Our study also showed that CBLC knockdown in EGFR wild-type cells increased the drug resistance to paclitaxel, which is widely used as a first-line chemotherapy drug in lung adenocarcinoma patients with EGFR wild-type or TKI resistance. Taken together, these findings indicate that CBLC might play a role in promoting cell mitosis and could be a potential biomarker of paclitaxel susceptibility for patients with EGFR wild-type lung adenocarcinoma.

Citation Format: Yi-Ping Lin, Shiao-Ya Hong, Yu-Rung Kao, Cheng-Wen Wu. CBLC is a potential biomarker for the susceptibility to paclitaxel in lung adenocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2642.

Upregulation of E3 Ubiquitin Ligase CBLC Enhances EGFR Dysregulation and Signaling in Lung Adenocarcinoma

CBLC (CBL proto-oncogene c) belongs to the CBL protein family, which has E3 ubiquitin ligase activity toward activated receptor tyrosine kinases. CBLC is frequently upregulated in non-small cell lung cancer (NSCLC), yet very little is known about the functions of CBLC in tumorigenesis. Here we show that CBLC is an epigenetically demethylated target and its expression can be upregulated in NSCLC after treatment with the DNA methylation inhibitor 5'-azacytidine. Depletion of CBLC significantly inhibited cell viability and clonogenicity in vitro and reduced tumor growth in a xenograft model. CBLC silencing further sensitized EGFR-mutated NSCLC cells to treatment with tyrosine kinase inhibitors. Conversely, ectopic expression of CBLC enhanced the activation of EGFR and downstream ERK1/2 signaling after ligand stimulation by competing with CBL for EGFR binding. Analysis of ubiquitin linkages on activated EGFR (aEGFR) revealed that CBLC ubiquitinated and positively regulated aEGFR stability through the conjugation of polyubiquitin by K6 and K11 linkages. This CBLC-mediated polyubiquitination promoted either preferential recycling of aEGFR back to the plasma membrane or trafficking to the cell nucleus. IHC analyses revealed a positive correlation between phospho-EGFR and CBLC in lung adenocarcinoma. In summary, we demonstrate a novel mechanism by which aEGFR escapes lysosomal degradation in a CBLC/ubiquitin-dependent manner to sustain its activation. Our work identifies CBLC as a potential diagnostic biomarker and also points to its utilization as a novel therapeutic target for NSCLC therapy.Significance: This work demonstrates the role of CBLC expression as a diagnostic biomarker and potential therapeutic target in lung adenocarcinoma. Cancer Res; 78(17); 4984-96. ©2018 AACR.

Hanging Hepato-Atrial Anastomosis in Deceased-Donor Liver Transplantation for Budd-Chiari Syndrome With Extensive Vena Cava Obliteration: A Case Report

INTRODUCTION

Although outcomes of liver transplantation (LT) have improved as the result of progress in surgical procedures, a failure to restore sufficient graft outflow may yield fatal consequences including graft dysfunction and even graft loss to date. In particular, patients with pre-existing obliterated venous drainage, such as those with Budd-Chiari syndrome (BCS), are at high risk of having venous complications followed by conventional LT. In selected cases, the transplant surgeons are compelled to modify the surgical procedures of LT from the conventional procedure.

METHODS

We describe an LT performed in a BCS patient with complete inferior vena cava (IVC) obstruction. A procedure that we named "hanging hepato-atrial anastomosis" was performed, in which 2 major modifications were made. One modification was the dissection of the lower inlet of the right atrium by use of a trans-abdominal approach and hepato-atrial anastomosis. This was performed by exposing the thoracic IVC through a trans-abdominal approach. The other modification was the manufacture of a blind pouch from the graft's infra-hepatic IVC without anastomosis.

RESULTS

Modifications were made possible as the result of meticulous examination of the patient's vascular anatomy before the operation. Fortunately, the patient had a heavy network of pre-vertebral veins that drained blood from the lower extremity and both kidneys to the azygos-hemi-azygos veins.

CONCLUSIONS

We learned that a meticulous assessment of vascular anatomy and complete understanding of hemodynamics are the keys to the successful LT for BCS in patients with extensive IVC abnormality. Thoracotomy may not be necessary to explore thoracic IVC when performing hepato-atrial anastomosis in LT for BCS.

Seizures in patients with acute pesticide intoxication, with a focus on glufosinate ammonium

The incidence and clinical aspects of seizures remain to be elucidated in patients with acute pesticide intoxication. The present study included subjects who ingested pesticide with the intention of committing suicide and were treated at Soonchunhyang University Hospital (Cheonan, Korea) between January 2011 and December 2014. We analyzed the incidence and characterized the type and frequency of seizure, from the medical records of 464 patients with acute pesticide intoxication, according to the pesticide class. The effect of seizure on the clinical outcome was assessed. The incidence of seizure was 31.5% in patients who ingested glufosinate ammonium {2-amino-4-[hydroxyl (methyl) phosphinoyl] butyrate; ammonium DL-homoalanin-4-yl (methyl) phosphinate}, followed by those who ingested pyrethroid (5.9%) or glycine derivatives (5.4%). All of the seizures developed between 12 and 24 h of pesticide ingestion and had ceased by 72 h after seizure initiation, following treatment with antiseizure medication. Generalized tonic-clonic seizures were the most commonly observed (85.7% of the cases). Multivariable logistic regression analysis showed that the effect of seizure on mortality was not statistically significant. In conclusion, glufosinate ammonium herbicide is the most common seizurogenic pesticide class. Seizure itself was not a risk factor for mortality in patients with acute glufosinate ammonium intoxication.

Correlates of non-adherence to antiretroviral therapy in a cohort of HIV-positive drug users receiving antiretroviral therapy in Hanoi, Vietnam

The HIV epidemic in Vietnam is concentrated, with high prevalence estimates among injection drug users and commercial sex workers. Socio-demographics, substance use and clinical correlates of antiretroviral therapy non-adherence were studied in 100 HIV-1 infected drug users receiving antiretroviral therapy for at least 6 months in Hanoi, Vietnam. All study participants were men with a mean age of 29.9 ± 4.9 years. The median duration on antiretroviral therapy was 16.2 ± 12.7 months; 83% reported 'very good' or 'perfect' adherence in the past 30 days on a subjective one-item Likert scale at time of study enrollment; 48% of participants reported drug use within the previous 6 months, with 22% reporting current drug use. Injection drug use with or without non-injection drug use in the past 6 months (95% C.I. 2.19, 1.30-3.69) and years on antiretroviral therapy (95% C.I. 1.43, 1.14-1.78) were correlated with suboptimal adherence. These findings support Vietnam's ongoing scale-up of harm reduction programmes for injection drug users and their integration with antiretroviral therapy delivery. Moreover, results highlight the need to identify and implement new ways to support high levels of antiretroviral therapy adherence as duration on antiretroviral therapy increases.

Abstract A40: CTEN prolongs EGFR signaling by reducing ligand-induced EGFR degradation

Epidermal growth factor receptor (EGFR) tyrosine kinase engages a vast array of signaling pathways regulating tissue development and homeostasis. The signal is normally induced by ligand binding (such as EGF) that activates the receptors and then the downstream molecules, which mediate cell fate decisions such as proliferation, migration, and differentiation. EGF binding not only turns on the EGFR activity; it also turns on the mechanisms to inactivate EGFR signaling. One way is the activation of c-Cbl, an E3 ubiquitin ligase that binds to tyrosine-phosphorylated EGFR and leads to ubiquitination of EGFR for lysosomal degradation. Dysregulated EGFR signaling either by up-regulation or aberrant activation of the receptor will trigger cellular events that contribute to tumor microenvironments and cancer formation.

Focal adhesions connect extracellular matrix to cytoskeletal networks and play critical roles in cell adhesion, migration, proliferation, and survival. They also crosstalk with growth factor receptors, such as EGFR to elicit a wider range of cellular responses, and may function as biosensors for microenvironments. Cten (C-terminal tensin like) is a focal adhesion molecule known to regulate cell adhesion and migration. Previously, we had shown that cten was up-regulated by EGF and mediated EGF induced cell migration. To further investigate cten's role in EGFR signaling pathway, we examined cten's effect on EGFR protein stability. Cten significantly reduced ligand-induced EGFR degradation through decreasing EGFR ubiquitination. This was accomplished by binding to c-Cbl in a phosphotyrosine-SH2 dependent fashion. A functional SH2 domain of cten was essential for its activities in promoting tumor cell migration, invasion, and colony formation. In addition to cell culture systems, EGFR levels were markedly enhanced in a cten tissue-specific knockin mouse model. By analysis of cten and EGFR expressions in human cancer samples, we found a positive association between cten and EGFR protein levels. Since cten regulates the activated EGFR level and plays roles in tumor migration/invasion, targeting of cten might have a beneficial effect on EGFR targeted therapies.

Citation Format: Shiao-Ya Hong, Yi-Ping Shih, Tianhong Li, Kermit Carraway, Su Hao Lo. CTEN prolongs EGFR signaling by reducing ligand-induced EGFR degradation. [abstract]. In: Proceedings of the Third AACR International Conference on Frontiers in Basic Cancer Research; Sep 18-22, 2013; National Harbor, MD. Philadelphia (PA): AACR; Cancer Res 2013;73(19 Suppl):Abstract nr A40.

CTEN prolongs signaling by EGFR through reducing its ligand-induced degradation

Activation of EGF receptor (EGFR) triggers signaling pathways regulating various cellular events that contribute to tissue development and function. Aberrant activation of EGFR contributes to tumor progression as well as therapeutic resistance in patients with cancer. C-terminal tensin-like (CTEN; TNS4) is a focal adhesion molecule that is a member of the tensin family. Its expression is upregulated by EGF and elevated CTEN mediates EGF-induced cell migration. In the presence of CTEN, we found that EGF treatment elevated the level of EGFR protein but not mRNA. The extended half-life of activated EGFR sustained its signaling cascades. CTEN reduced ligand-induced EGFR degradation by binding to the E3 ubiquitin ligase c-Cbl and decreasing the ubiquitination of EGFR. The Src homology 2 domain of CTEN is not only required for binding to the phosphorylated tyrosine residue at codon 774 of c-Cbl, but is also essential for the tumorigenicity observed in the presence of CTEN. Public database analyses indicated that CTEN mRNA levels are elevated in breast, colon, lung, and pancreas cancers, but not correlated with EGFR mRNA levels in these cancers. In contrast, immunohistochemistry analyses of lung cancer specimens showed that CTEN and EGFR protein levels were positively associated, in support of our finding that CTEN regulates EGFR protein levels through a posttranslational mechanism. Overall, this work defines a function for CTEN in prolonging signaling from EGFR by reducing its ligand-induced degradation.

Phylogenetic analysis, expression patterns, and transcriptional regulation of human CTEN gene

Cten is a focal adhesion molecule and a member of the tensin family. Its expression is highly enriched in the prostate and placenta, suggesting that cten gene might be closely associated with mammalian species. Recent studies have reported that cten expression is frequently up-regulated in a variety of cancers and its levels appear to correlate with tumorigenicity. Here, we have (1) analyzed cten sequences of various species to build a phylogenetic tree, (2) examined cten mRNA levels in human and mouse tissues to establish its expression profiles, and (3) determined the promoter region of human CTEN gene in cell lines and in a mouse model to understand its transcriptional regulation. Our analyses indicate that all currently known cten genes are present in mammals. The prostate and placenta are the two most cten abundant tissues in human and mouse, meanwhile brain and lung also express low levels of cten. Results from cell culture reporter assays demonstrate that a 327-bp fragment is the shortest functional promoter. All functional promoter constructs produce 40- to 160-fold increases in luciferase reporter activities in normal prostate cells, whereas lower activities (<40-fold) are detected in non-prostatic cell lines. To evaluate CTEN promoter activity in mice and develop a new tissue specific Cre recombinase mouse model, we have established pCTEN-Cre:R26R mice by crossing R26R β-galactosidase reporter mice with pCTEN-Cre transgenic mice, in which the 327-bp cten promoter drives the expression of Cre recombinase. X-gal analysis has shown strong β-galactosidase activities in the prostate, brain, and few other tissues in pCTEN-Cre:R26R mice. Altogether, we have identified the promoter region of human cten gene and provided a useful tool for investigating cell lineages and generating tissue-specific knockout or knockin mice.

Update on World Health Organization HIV drug resistance prevention and assessment strategy: 2004-2011

The HIV drug resistance (HIVDR) prevention and assessment strategy, developed by the World Health Organization (WHO) in partnership with HIVResNet, includes monitoring of HIVDR early warning indicators, surveys to assess acquired and transmitted HIVDR, and development of an accredited HIVDR genotyping laboratory network to support survey implementation in resource-limited settings. As of June 2011, 52 countries had implemented at least 1 element of the strategy, and 27 laboratories had been accredited. As access to antiretrovirals expands under the WHO/Joint United Nations Programme on HIV/AIDS Treatment 2.0 initiative, it is essential to strengthen HIVDR surveillance efforts in the face of increasing concern about HIVDR emergence and transmission.

A case of methanol intoxication caused by methomyl pesticide ingestion

When clinicians treat patients with pesticide poisoning, they often pay attention only to the chief toxic agent and ignore the toxicity of the pesticide’s additives or solvents. Occasionally, however, a solvent (e.g. methanol) may itself be the cause of poisoning. We report a case of acute methanol intoxication that occurred after ingestion of a methomyl pesticide that contained methanol as an additive. A 49-year-old man was brought to the emergency department in an unconscious state after ingestion of 20 ml of a carbamate pesticide (chief ingredient: methomyl; active ingredient: methanol). Upon arrival, he was semicomatose and did not breathe spontaneously; however, his cholinesterase level was within normal limits and cholinergic symptoms were not observed. High anion gap metabolic acidosis was present. His blood ethanol level was 74.8 mg/dL. The urine methanol level was 55.60 mg/dL, and urine ethanol level was 22.0 mg/dL. He was treated with hemodialysis; subsequently, his metabolic acidosis resolved and he returned to normal mental status. We guessed that methanol, as the solvent of the methomyl, had produced the symptoms. When treating pesticide-poisoned patients, clinicians should identify the solvent used in the pesticide, because solvents such as methanol may exacerbate the symptoms of poisoned patients.

Reduced expression of angiopoietin-1 in Hantaan virus-infected human umbilical vein endothelial cell increases their permeability

Hemorrhagic fever with renal syndrome (HFRS) caused by Hantaan virus (HTNV) is characterized by vascular hemorrhage and acute renal failure. Angiopoietin-1 (Ang-1) is a glycoprotein that maintains vessel integrity and reduces endothelial permeability. We found that in HTNV-infected human umbilical vein endothelial cells (HUVECs) the levels of Ang-1 mRNA and protein were reduced on days 2 and 3 post-infection (p.i.), when endothelial permeability was increased. The HTNV-stimulated permeability was reduced by treatment of HUVECs with Ang-1. The plasma Ang-1 level was lower in HFRS patients than in healthy persons. Paired plasma samples of HFRS patients revealed markedly lower Ang-1 levels during the acute phase of HFRS as compared to the convalescent phase. These findings suggested that HTNV reduced the Ang-1 expression in endothelial cells that might play an important role in the increase of vascular permeability in HFRS.

Structure and stability of molybdenum sulfide fullerenes

MoS2 nanooctahedra are believed to be the smallest stable closed-cage structures of MoS2, i.e., the genuine inorganic fullerenes. Here a combination of experiments and density functional tight binding calculations with molecular dynamics annealing are used to elucidate the structures and electronic properties of octahedral MoS2 fullerenes. Through the use of these calculations MoS2 octahedra were found to be stable beyond nMo > 100 but with the loss of 12 sulfur atoms in the six corners. In contrast to bulk and nanotubular MoS2, which are semiconductors, the Fermi level of the nanooctahedra is situated within the band, thus making them metallic-like. A model is used for extending the calculations to much larger sizes. These model calculations show that, in agreement with experiment, the multiwall nanooctahedra are stable over a limited size range of 104-105 atoms, whereupon they are converted into multiwall MoS2 nanoparticles with a quasi-spherical shape. On the experimental side, targets of MoS2 and MoSe2 were laser-ablated and analyzed mostly through transmission electron microscopy. This analysis shows that, in qualitative agreement with the theoretical analysis, multilayer nanooctahedra of MoS2 with 1000-25 000 atoms (Mo + S) are stable. Furthermore, this and previous work show that beyond approximately 105 atoms fullerene-like structures with quasi-spherical forms and 30-100 layers become stable. Laser-ablated WS2 samples yielded much less faceted and sometimes spherically symmetric nanocages.

Phylogenetic analysis of protozoa in the rumen contents of cow based on the 18S rDNA sequences

AIMS

To examine the diversity of protozoa in the rumen contents of cow.

METHODS AND RESULTS

Protozoa that inhabit the rumen were detected by PCR using protozoan-specific primers. Libraries of protozoan rDNA sequences were constructed from rumen fluid, solid tissues and epithelium. Twenty-three clones isolated from rumen fluid fell into two genera identified as Entodinium (69.6% of clones) and Epidinium (31.4% of clones). Of the clones isolated from rumen fluid, a moderate number were unidentifiable (30.4%).

CONCLUSIONS

The predominant protozoan genus identified in the whole rumen belonged to the Entodinium group (81.1%). Protozoa were not detected in the rumen epithelium.

SIGNIFICANCE AND IMPACT OF THE STUDY

These findings suggest that rumen fluid and solid tissues contain different protozoan populations that may play specific roles in rumen function. Quantitative PCR techniques and a more specific set of phylogenetic probes that distinguish between protozoan species are needed to determine the significance of newly identified groups and to determine the distribution of identified protozoan clusters in rumen microbial communities.

Cloning and characterization of ce/8A gene from Rhizobium leguminosarum bv. trifolii 1536

AIMS

To isolate the cellulase gene from Rhizobium leguminosarum bv. trifolii 1536.

METHODS AND RESULTS

By the shot-gun method a clone (cel8A) harbouring 3.1 kb genomic DNA fragment from R. leguminosarum bv. trifolii 1536 was obtained. The cel8A gene coded 348 amino acids and it belongs to the glycosyl hydrolase family 8. The molecular mass of Cel8A protein induced from Escherichia coli DH5alpha, appeared to be 35 kDa. The optimum pH and optimum temperature was 7.0, and about 30 degrees C for its enzymatic activity respectively.

CONCLUSIONS

R. leguminosarum bv. trifolii 1536 had cel8A gene having an open reading frame of 1047 bp coded for the activity of hydrolyzation of carboxymethyl cellulose.

SIGNIFICANCE AND IMPACT OF THE STUDY

The production of celluloytic enzyme by R. leguminosarum bv. trifolii was confirmed, which would play specific roles in rhizobia. Future study should focus on its role in the infection and nodulation phenomena.

Reuse of wastewater sludge with marine clay as a new resource of construction aggregates

The disposal of sludge from wastewater treatment presents highly complex problems to any municipality. Most of the sludge disposal methods have varying degrees of environmental impact. Hence, it is necessary to explore potential areas of reuse in order to alleviate sludge disposal problems and to conserve natural resources. Industrial sludge and marine clay are two forms of high-volume wastes. Using these wastes as a resource of raw materials to produce construction aggregates would enable large-scale sludge reuse. The aggregates were produced at various sludge-clay combinations containing 0, 20, 50, 80 and 100% clay contents, respectively. The pelletized aggregates displayed lower particle densities ranged between 1.48 and 2.25 g/cm3, compared to the density of granite at 2.56 g/cm3. Good 28-day concrete compressive strength of 38.5 N/mm2 achieved by the 100% sludge aggregate was comparable to the value of 38.0 N/mm2 achieved of the granite control specimens. The leachate contamination levels from the aggregates after 150 days were found acceptable when used in concrete, indicating insignificant environmental contamination. The heat flow study showed increases in heat flow at the temperatures of 480 degrees C and between 660 degrees C and 900 degrees C, indicating a need for the extension of heating time around these temperatures.

A comparison of ultrasound treatment on primary and secondary sludges

Ultrasound treatment of primary and secondary sludges was conducted to improve the qualities of sludges for the anaerobic digestion. The impacts of different sonication times, sonication densities and solids concentrations on ultrasonication efficiency were examined. The experimental results indicated that the significant reduction in particle size and increase in soluble organics could be achieved, implying that ultrasonication could offer a feasible treatment method to efficiently disintegrate sludge. The greater decrease in particle size and increase in soluble organics of sludge indicated that the secondary sludge has a more remarkable improvement after sonication over the primary sludge. With respects to the extent of disintegration and energy consumption, higher sonication density performed more effectively in terms of specific energy. There exists an optimal solids concentration range for both the sludges for optimum sonication. Within the optimal solids concentration range, efficient sonication can be effected and sludge would be disintegrated efficiently. The ultrasound would be attenuated by scattering and absorption if the solids concentration exceeds the optimal range. It appeared from the study that the mechanical shear forces caused by ultrasonic cavitation could be a key factor for sludge disintegration and collapse of cavitation bubbles could significantly alter the sludge characteristics.

Manufacturing artificial aggregates from industrial sludge and marine clay with addition of sodium salt

The potential of converting industrial sludge and dredged marine clay into building and construction materials as an alternative to disposal was investigated in this study. The industrial sludge was mixed with marine clay at various compositions and was shaped into round pellets to be used as concrete aggregates. The pellets were then dried and transferred into a high temperature kiln where they were heated at 1,135 degrees C. The artificial aggregates were more porous then the normal granite aggregate. The occurrence of this condition was suspected to be attributed to two factors, viz. the firing temperature and the amount of sodium in the aggregates. To validate this hypothesis, the aggregates with and without added sodium chloride were fired at temperatures of 1,100 and 1, 200 degrees C. Results showed a reduction in the densities of the aggregates with the addition of sodium chloride and the increase in firing temperature.

4G/5G polymorphism of the plasminogen activator inhibitor-1 gene and insertion/deletion polymorphism of the tissue-type plasminogen activator gene in atherothrombotic stroke

BACKGROUND AND PURPOSE

Decreased fibrinolytic capacity due to increased plasminogen activator inhibitor-1 (PAI-1) activity and decreased tissue-type plasminogen activator (t-PA) activity has been associated with hypertension or atherothrombotic disorders. The aims of this study were to observe associations of the genetic polymorphism for PAI-1 and t-PA with hypertension and atherothrombotic stroke, and to elucidate whether impaired fibrinolytic activity in atherothrombotic stroke was related to atherothrombosis per se or to other risk factors such as hypertension.

METHODS

Patients with atherothrombotic stroke (n = 60), hypertension (n = 100), and control subjects (n = 100) were enrolled. We genotyped all subjects for 4G/5G polymorphism in the promoter region of the PAI-1 gene and the Alu-repeat insertion/deletion (I/D) polymorphism in intron h of the t-PA gene by polymerase chain reaction and endonuclease digestion.

RESULTS

The frequency of the 4G/4G genotype of PAI-1 was significantly higher in the atherothrombotic stroke patients than the control subjects (41.7 versus 21%; p = 0.005), but not in the hypertensive subjects. There was a significant association between 4G/4G genotype of PAI-1 and atherothrombotic stroke (adjusted odds ratio = 3.11, 95% confidence interval 1.18-8.15), adjusting for age, sex, total cholesterol, low-density lipoprotein, triglyceride, and body mass index. However, the number of the I/I genotype of t-PA in the atherothrombotic stroke or hypertensive patients was virtually identical to the control subjects.

CONCLUSION

Our results suggest that the 4G/4G genotype of the PAI-1 gene is significantly associated with an increased risk of atherothrombotic stroke. This finding also supports that impaired fibrinolytic activity in atherothrombotic stroke is related to atherothrombosis per se, but not to hypertension, one of the most important risk factors of atherothrombotic stroke.

The effect of a disrupted yhjQ gene on cellular morphology and cell growth in Escherichia coli

The 5' upstream region of the cellulose synthase operon ( bcs operon) has been isolated by cloning from Escherichia coli. A gene encoding YhjQ is located 1.0 kb upstream of the bcs operon in E. coli. The function of YhjQ remains unknown. Insertional inactivation of the yhjQ gene causes abnormal cell division, resulting in incomplete partition of the chromosome and filamentous cells of various sizes. These results suggest that the product of yhjQ may affect normal doubling and cellular morphology.

Is tumor necrosis factor genotype (TNFA2/TNFA2)a genetic prognostic factor of an unfavorable outcome in IgA nephropathy?

The purpose of this study was to examine whether there are the associations between TNF alpha and TNF beta gene polymorphisms and the development and progression of Ig A nephropathy (IgAN). A cross-sectional study on TNF alpha and TNF betagene polymorphisms by polymerase chain reaction with restriction fragment length poly-morphisms was performed on 76 patients with primary IgAN confirmed by renal biopsy and 100 healthy controls. The allele with G-->A substitution was designated as TNFA2 for the TNF alpha gene and TNFB2 for the TNF betagene. A patient in whom dialysis treatment was started or whose serum creatinine became double or over during the follow-up duration was designated as a "progressor". The TNFA2/ TNFA2 genotype was more prevalent in the progressor than in the non-pregressor group (20.0 vs 3.3%, p<0.05). Clinical factors such as serum creatinine, systolic and diastolic blood pressure (p<0.001, respectively) were higher and pathologic factor such as Grade IV or V renal lesions was more prevalent (p<0.01) in the progressor than in the non-progressor group. Therefore, TNFA2/TNFA2 genotype may be a risk factor for the progression of IgAN.

New frontiers in the continuum of dental education

During the past 150 years, dental education and training have changed from an apprenticeship to a university-based dental school. The future of dental education will be shaped by changing demographics, advances in technology, and a greater integration of science and research into the dental profession. We are entering an age of interdisciplinary practice, where dentistry provides oral health care as an integral part of an individual's overall health care.

Cloning of the cel9A gene and characterization of its gene product from marine bacterium Pseudomonas sp. SK38

The yellow-pigmented bacterial strain causing green spot rot and death of layer was isolated from Porphyra dentata. This strain has been identified as Pseudomonas sp., harboring agarase, xylanase, and protease activity, as well as carboxymethyl-cellulase (CMCase). Using genomic DNA from the Pseudomonas sp. SK38 digested with Sau3AI and ligated into pBluescript II KS+, we isolated a cel gene encoding a CMCase in Pseudomonas sp. SK38. A 4.5-kb fragment was subcloned into pKR400. The structure of the cel9A gene consists of an open reading frame of 1,521 bp starting with a GTG start codon and ending with a TAG stop codon. It thus encodes 506 amino acid residues of a protein with a calculated molecular weight of 52,636 daltons plus a signal peptide of 22 amino acids. The deduced amino acid sequence of the cel9A protein is similar to the same protein of Clostridium thermocellum. It contains, in particular, the two conserved regions of the glycoside hydrolase family 9. The apparent molecular mass of the Cel9A protein is 52 kDa as estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The enzyme is most active at pH 6-7 and an optimal temperature of around 30 degrees C.

The effect of charge increase on the specificity and activity of a short antimicrobial peptide

By using short linear antimicrobial peptides as a model system, the effect of peptide charge on the specificity between Candida albicans (fungi) and Gram-positive bacteria was investigated. In a present study, we added and/or deleted lysine residue(s) at the C-terminal and/or N-terminal end(s) of an antimicrobial peptide (KKVVFKVKFK-NH(2)) and synthesized the peptides that had similar alpha helical structures in a lipid membrane mimic condition. The increase of peptide charge improved antifungal activity without the change of antibacterial activity. Structure-activity relationship study about the peptides revealed that the net positive charge must play an important role in the specificity between C. albicans and Gram-positive bacteria and the increase of the net positive charge without the moderate change of secondary structure could improve activity for C. albicans rather than Gram-positive bacteria.

Inhibition of tumor growth and metastasis by Korean mistletoe lectin is associated with apoptosis and antiangiogenesis

The mistletoe lectins are major active components in the extract of European mistletoes that have been widely used in adjuvant chemotherapy of cancer. This study was performed to investigate the mechanism of anticancer and antimetastatic activity of the purified Korean mistletoe lectin (Viscum album L. coloratum agglutinin, VCA). C57BL6 mice inoculated with B16-BL6 melanoma cells and treated with VCA were assessed for survival and metastasis. The induction of apoptosis of B16-BL6 cells by VCA was investigated by morphological changes, DNA fragmentation characteristics, and cell cycle analysis. The antiangiogenic activity of VCA was also measured by the CAM (choriallantoic membrane) assay. Length of survival of mice was increased and lung metastasis was inhibited by VCA. Treatment of cells with VCA resulted in growth suppression, nuclear morphological changes, DNA fragmentation, and an increased fraction of cells in sub-G1 consistent with apoptosis. Antiangiogenesis of VCA was assessed by CAM assay, where vessel growth induced by fat emulsion was decreased. These results suggest that VCA inhibits tumor growth and metastasis by increasing apoptosis and inhibiting angiogenesis.

Cloning and characterization of an intracellular isoamylase gene from Pectobacterium chrysanthemi PY35

The gene encoding an intracellular isoamylase from the Pectobacterium chrysanthemi PY35 was cloned in Escherichia coli DH5alpha and sequenced. The isoamylase gene (amyX) had an open reading frame of 1974 bp encoding 657 amino acid residues with a calculated molecular weight of 74,151 Da. The molecular weight of the enzyme was also estimated to be 74 kDa by activity staining of a SDS-PA gel. Isoamylase from P. chrysanthemi PY35 had 59% pairwise amino acid identity with glycogen debranching enzyme from E. coli and contained the four regions conserved among all amylolytic enzymes. The isoamylase was optimally active at pH 7 and 40 degrees C. AmyX hydrolyzed alpha-1,6-glycosidic linkages of amylopectin, while did not hydrolyze alpha-1,4-glycosidic linkages of amylose.

mRNA expression of urokinase and plasminogen activator inhibitor-1 in human crescentic glomerulonephritis

AIMS

Weak staining for urokinase-plasminogen activator (uPA), tissue type plasminogen activator (tPA), or plasminogen activator inhibitor-1 (PAI-1) confined to crescents has been described in a few cases of severe crescentic glomerulonephritis. We evaluated the molecular mechanism by which these proteins are increased or induced within crescents.

METHODS AND RESULTS

We examined uPA, tPA and PAI-1 mRNA expression in 12 renal biopsies with crescentic glomerulonephritis, and in six control renal biopsies with no detectable abnormalities by RNA in-situ hybridization. The expressions of uPA, tPA and PAI-1 proteins were also assessed by immunofluorescence. To better determine the cellular origin of uPA and PAI-1 transcripts, CD68 protein was studied by immunohistochemistry on the same sections on which in-situ hybridization had been performed. In controls, there were very low level signals of uPA and PAI-1 mRNAs in a few glomerular epithelial cells (GECs). Specific signals of uPA and PAI-1 mRNAs were detected in the cells forming crescents in all the cases with crescentic glomerulonephritis. However, weak expression of mRNA for tPA was detected in two cases only. Immunostaining for uPA and PAI-1 was positive in some but not all, cases of crescentic glomerulonephritis. A double-labelling study showed that the signal for PAI-1 and uPA mRNAs was mainly in CD68- cells.

CONCLUSIONS

Local accumulation of uPA or PAI-1 in crescents is associated with enhanced mRNA expression of these proteins. The up-regulation of PAI-1 mRNA by GECs, in particular, could play a major role in the formation of persistent fibrin deposits and progression of the lesions in crescents. Whether up-regulation of uPA is an epiphenomenon or plays a pathogenic role in the formation of crescents remains to be clarified.

Enzymatic activation of autotaxin by divalent cations without EF-hand loop region involvement

Autotaxin (ATX) is a recently described member of the nucleotide pyrophosphatase/phosphodiesterase (NPP) family of proteins with potent tumor cell motility-stimulating activity. Like other NPPs, ATX is a glycoprotein with peptide sequences homologous to the catalytic site of bovine intestinal alkaline phosphodiesterase (PDE) and the loop region of an EF-hand motif. The PDE active site of ATX has been associated with the motility-stimulating activity of ATX. In this study, we examined the roles of the EF-hand loop region and of divalent cations on the enzymatic activities of ATX. Ca(2+) or Mg(2+) was each demonstrated to increase the PDE activity of ATX in a concentration-dependent manner, whereas incubation of ATX with chelating agents abolished this activity, indicating a requirement for divalent cations. Non-linear regression analysis of enzyme kinetic data indicated that addition of these divalent cations increases reaction velocity predominantly through an effect on V(max.) Three mutant proteins, Ala(740)-, Ala(742)-, and Ala(751)-ATX, in the EF-hand loop region of ATX had enzymatic activity comparable to that of the wild-type protein. A deletion mutation of the entire loop region resulted in slightly reduced PDE activity but normal motility-stimulating activity. However, the PDE activity of this same deletion mutant remained sensitive to augmentation by cations, strongly implying that cations exert their effect by interactions outside of the EF-hand loop region.

Characterization of a novel allele of glucose oxidase from a Korean wild type strain of Aspergillus niger

We have identified a novel allele of the glucose oxidase (GO, EC1.1.3.4) gene (GO) from a Korean wild type strain of Aspergillus niger, ACMO4, with an increased GO activity in culture filtrate. Southern blot analyses of GO from ACMO4 (GO-ACMO4) revealed that the gene was present as a single copy in the genome of A. niger. However, its sequence differs from that of GO from A. niger ATCC 9029 (GO-ATCC9029). GO-ACMO4 appears to be a functional gene based on the fact that it is enzymatically active when heterologously expressed in yeast. Sequence comparisons of the coding region of GO-ACMO4 revealed 16 nucleotide changes that resulted in four amino acid substitutions; T432D, G517D, G530S, and Q542R. The GO proteins from both ATCC 9029 and ACMO4 were heterologously expressed, purified, and compared biochemically. The two enzymes showed no difference in their apparent Km value for glucose (30 mM), but the Vmax of GO-ACMO4 (515.6 unit/mg) was 10% higher than that of GO-ATCC 9029, resulting in a 10% higher specific activity.

Tactile-spatial and cross-modal attention effects in the second somatosensory and 7b cortical areas of rhesus monkeys

This study analyzed neuronal responses in the second somatosensory (SII) and 7b cortical areas during a selective attention task. Cues directed attention to one of three simultaneous stimuli: vibrotactile stimuli applied to mirror sites on both hands or to a similarly timed auditory tone. Two stimulus patterns appeared with equal probability for the cued stimulus: a constant amplitude sinewave or the latter with a superimposed brief amplitude pulse midway in the trial. Uncued stimuli always contained amplitude pulses. Monkeys demonstrated whether an amplitude pulse at the cued location was present or absent by making appropriately rewarded up and down foot pedal movements. Cue location and stimulus pattern varied trial-wise and pseudo-randomly. Average firing rates to vibrotactile stimuli in 82 of 181 SII cells and 13 of 22 area 7b cells differed significantly during at least one epoch for trials cued to the contralateral hand when compared to trials cued to the ipsilateral hand or auditory stimulus. Predominant were relatively suppressed firing rates during times prior to the epoch containing the amplitude pulses or enhanced activity during and after these pulses. Generally, different cells showed suppression early vs enhancement later in a trial. Analyses of the ratio between firing rates before and during the amplitude pulses suggested improved evoked signals to the amplitude pulses. The discussion considers attention as a mechanism for reducing distractions, early in the trial through suppressing these signals, or for selectively increasing response magnitudes in the cued channel, especially around times when amplitude pulses were present or absent.