Adverse respiratory patterns in near-term spontaneously breathing newborn lambs with elevated airway liquid volumes at birth

Introduction

Recent evidence indicates that respiratory distress (RD) in near-term infants is caused by elevated airway liquid (EL) volume at the beginning of air-breathing after birth. While the adverse effects EL volumes on newborn lung function are known, the effects on respiratory control and breathing patterns shortly after birth (<4 h) are unknown. We investigated the effects of EL volumes on cardiorespiratory function and breathing patterns in spontaneously breathing near-term newborn lambs in the first hours after birth.

Methods

At 137-8 days gestation (2-3 days prior to delivery; term ∼147 days), sterile surgery was performed on fetal sheep (n = 17) to implant catheters and blood flow probes. At 140 days, lambs were delivered via caesarean section under spinal anaesthesia. Airway liquid volumes were adjusted to mimic the level expected following vaginal delivery (∼10 ml/kg; Controls; n = 7), or elective caesarean section (∼30 ml/kg; elevated airway liquid group; EL; n = 10). Spontaneous breathing and cardiorespiratory parameters were recorded over four hours after birth. Non-invasive respiratory support with supplemental oxygen was provided if required.

Results

EL lambs required higher inspired oxygen levels (p = 0.0002), were less active (p = 0.026), fed less (p = 0.008) and had higher respiratory morbidity scores than Controls (p < 0.0001). EL lambs also displayed higher rates of breathing patterns associated with RD, such as expiratory braking and tachypnoea. These patterns were particularly evident in male EL lambs who displayed higher levels of severe respiratory morbidity (e.g., expiratory braking) than female EL lambs.

Conclusion

The study demonstrates that EL volumes at birth trigger respiratory behaviour and breathing patterns that resemble clinically recognised features of RD in term infants.

Anxiety and dysautonomia symptoms in patients with a NaV1.7 mutation and the potential benefits of low-dose short-acting guanfacine

PURPOSE

Guanfacine is an α2A-adrenergic receptor agonist, FDA-approved to treat attention-deficit hyperactivity disorder and high blood pressure, typically as an extended-release formulation up to 7 mg/day. In our dysautonomia clinic, we observed that off-label use of short-acting guanfacine at 1 mg/day facilitated symptom relief in two families with multiple members presenting with severe generalized anxiety. We also noted anecdotal improvements in associated dysautonomia symptoms such as hyperhidrosis, cognitive impairment, and palpitations. We postulated that a genetic deficit existed in these patients that might augment guanfacine susceptibility.

METHODS

We used whole-exome sequencing to identify mutations in patients with shared generalized anxiety and dysautonomia symptoms. Guanfacine-induced changes in the function of voltage-gated Na+ channels were investigated using voltage-clamp electrophysiology.

RESULTS

Whole-exome sequencing uncovered the p.I739V mutation in SCN9A in the proband of two nonrelated families. Moreover, guanfacine inhibited ionic currents evoked by wild-type and mutant NaV1.7 encoded by SCN9A, as well as other NaV channel subtypes to a varying degree.

CONCLUSION

Our study provides further evidence for a possible pathophysiological role of NaV1.7 in anxiety and dysautonomia. Combined with off-target effects on NaV channel function, daily administration of 1 mg short-acting guanfacine may be sufficient to normalize NaV channel mutation-induced changes in sympathetic activity, perhaps aided by partial inhibition of NaV1.7 or other channel subtypes. In a broader context, expanding genetic and functional data about ion channel aberrations may enable the prospect of stratifying patients in which mutation-induced increased sympathetic tone normalization by guanfacine can support treatment strategies for anxiety and dysautonomia symptoms.

Respiratory patterns in spontaneously breathing near-term lambs delivered by caesarean section under spinal anaesthesia

Introduction

The transition to newborn life has typically been studied in intubated and mechanically ventilated newborn lambs delivered via caesarean section (CS) under general anaesthesia. As a result, little is known of the spontaneous breathing patterns in lambs at birth, particularly those at risk of developing respiratory distress (RD). We have developed a method for delivering spontaneously breathing near-term lambs to characterise their breathing patterns in the immediate newborn period.

Methods

At 137-8 days gestation (2-3 days prior to delivery; term ∼147 days), fetal lambs (n = 7) were partially exteriorised for instrumentation (insertion of catheters and flow probes) before they were returned to the uterus. At 140 days, lambs were delivered via CS under light maternal sedation and spinal anaesthesia. Lambs were physically stimulated and when continuous breathing was established, the umbilical cord was clamped. Breathing patterns were assessed by measuring intrapleural and upper-tracheal pressures during the first four hours after birth.

Results

Newborn lambs display significant heterogeneity in respiratory patterns in the immediate newborn period that change with time after birth. Seven distinct breathing patterns were identified including: (i) quiet (tidal) breathing, (ii) breathing during active periods, (iii) breathing during oral feeding, (iv) tachypnoea, (v) expiratory braking manoeuvres, (vi) expiratory pauses or holding, and (vii) step changes in ventilation.

Conclusions

We have described normal respiratory behaviour in newborn lambs, in order to identify respiratory behaviours that are indicative of RD in term newborn infants.

Assessing lung aeration using ultrasound after birth in near-term lambs at risk of respiratory distress

Background

Optimizing respiratory support after birth requires real-time feedback on lung aeration. We hypothesized that lung ultrasound (LUS) can accurately monitor the extent and progression of lung aeration after birth and is closely associated with oxygenation.

Methods

Near-term (140 days gestation, term ∼147 days), spontaneously breathing lambs with normal (controls; n = 10) or elevated lung liquid levels (EL; n= 9) were delivered by Caesarean section and monitored for four hours after birth. LUS (Phillips CX50, L3-12 transducer) images and arterial blood gases were taken every 5-20 min. LUS images were analyzed both qualitatively (grading) and quantitatively (using the coefficient of variation of pixel intensity (CoV) to estimate the degree of lung aeration), which was correlated with the oxygen exchange capacity of the lungs (Alveolar-arterial difference in oxygen; AaDO₂).

Results

Lung aeration, measured using LUS, and the AaDO₂ improved over the first 4 h after birth. The increase in lung aeration measured using CoV of pixel intensity, but not LUS grade, was significantly reduced in EL lambs compared to controls (p = 0.02). The gradual decrease in AaDO₂ after birth was significantly correlated with increased lung aeration in both control (grade, r²= 0.60, p < 0.0001; CoV, r²= 0.54, p < 0.0001) and EL lambs (grade, r²= 0.51, p < 0.0001; CoV, r²= 0.44, p < 0.0001).

Conclusions

LUS can monitor lung aeration and liquid clearance after birth in spontaneously breathing near-term lambs. Image analysis techniques (CoV) may be able detect small to moderate differences in lung aeration in conditions with lung liquid retention which are not readily identified using qualitative LUS grading.

Abstract 271: Monitoring of CCR2 and CCR5 expression on circulating myeloid derived suppressor cells (MDSCs) in non-small cell lung cancer as a correlate of minimum residual disease

Objectives: Myeloid derived suppressor cells (MDSCs) are immature cells that aid in cancer progression and dissemination via immune system suppression. Previous work has shown that CCR 2 (C-C chemokine receptor) and CCR 5 expression on MDSCs is increased in non-small cell lung cancer (NSCLC). We hypothesized that patients with lung cancer will have detectable peripheral MDSCs with CCR2 and CCR5 expression preoperatively, that it would decrease immediately postoperatively, and then increase longitudinally if tumor recurs.

Materials & Methods: As part of a prospective longitudinal study, whole blood samples were obtained from patients suspected to have primary lung cancer prior to surgery. Patients were excluded if they were minors, could not provider consent, had malignancy within the past 10 years or any immunosuppressive condition. Blood samples were obtained prior to surgery or at follow-up in clinic and processed within 1 hour of acquisition. We stained samples via 2 different methods: 1) whole blood and 2) peripheral blood mononuclear cells (PBMC) extracted from Ficoll density gradient and determined that whole blood staining had superior results. Samples were analyzed via flow cytometer and gated after defining MO (monocytic)-MDSCs as CD33+HLADRlow/-CD14+ and PMN-MDSCs as CD33+HLADR-CD15+. MDSCs were reported as a percentage of live leukocytes and means were reported with T-test performed for statistical analysis.

Results: A total of 18 patients were recruited with a median age of 69 years (63.8-75) and 61% (11/18) females. Adenocarcinoma was present in 16, carcinoid tumor in 1 and both adenocarcinoma and carcinoid tumor in 1 patient. Stage I and Stage II were the most common (66.7% and 22.2%, respectively). Majority of the tumors were in the right upper lobe (55.6%). There were 7 healthy controls with a median age of 29 years (28-43) and 71% females. There was a significantly increased proportion of MO-MDSCs in NSCLC patients preoperatively compared to healthy controls (11.64% versus 5.02%, p = 0.02). CCR2+CCR5+ MO-MDSCs were 0.85% in patients versus 0.06% in controls (p=0.04). No differences were noted with PMN-MDSCs. Five patients had post-operative follow up (mean 152 days) with an average decrease of 63% in MO-MDSCs, 68% in CCR2+CCR5+ MO-MDSCs and no recurrence of tumor on CT scans.

Conclusion: Early results of this on-going study demonstrate the detection of circulating CCR2+CCR5+ MO-MDSCs in the preoperative whole blood of NSCLC patients compared to healthy controls. Resection of the tumor is associated with a decrease of these MO-MDSCs after treatment. We are evaluating if any increase in CCR2+CCR5+ MO-MDSC in long term will allow us to use it as an adjuvant tool along with CT monitoring as a biomarker of residual or recurrent disease.

Citation Format: Hamza Khan, Anas Awan, Maria Shishikura, Carley Blevins, Kristen Rodgers, Yuping Mei, Wasay Nizam, Shun Ishiyama, Yun Chen, Richard Battafarano, Errol Bush, Stephen Broderick, Stephen Yang, Hajime Orita, Peng Huang, Ada Tam, Jinny Ha, Franck Housseau, Malcolm Brock. Monitoring of CCR2 and CCR5 expression on circulating myeloid derived suppressor cells (MDSCs) in non-small cell lung cancer as a correlate of minimum residual disease [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 271.

Clinical Significance of Plasma CD9-Positive Exosomes in HIV Seronegative and Seropositive Lung Cancer Patients

Simple Summary

The role of exosomes in HIV (human immunodeficiency virus) as well as in cancer patients seems to be pivotal. The aim of our retrospective study was to assess the potential clinical value of CD9-positive plasma exosomes in lung cancer patients, patients with lung granulomas, healthy individuals, and HIV-positive patients with or without lung cancer. This study shows that CD9-positive plasma exosome concentrations differ between healthy controls, patients with immunocompetent pulmonary granulomas and patients with lung cancer. In addition, CD9-positive plasma exosomes are increased in HIV seropositive and HIV seronegative lung cancer patients compared to healthy controls, while chemotherapy-treated lung cancer patients have lower plasma exosome levels. This study also shows that in chemotherapy-naïve patients, plasma exosome levels are directly correlated with a prognosis with higher concentrations being associated with a longer, overall survival. These findings further support previous literature on the translational significance of total plasma exosomes in cancer patients, despite different immunological contexts.

Abstract

Recently, the role of exosomes in the progression of both cancer and HIV (human immunodeficiency virus) has been described. This study investigates the clinical significance of CD9-positive plasma exosomes in lung cancer patients, healthy individuals, and HIV-positive patients with or without lung cancer. Using a verified with transmission electron microscopy double-sandwich ELISA technique, plasma-derived exosomes were isolated and quantified from 210 lung cancer patients (including 44 metastatic patients with progressive disease after chemotherapy), 49 healthy controls, 20 patients with pulmonary granulomas, 19 HIV+ patients with lung cancer, 31 HIV+ patients without cancer, and 3 HIV+ patients with pulmonary granulomas. Plasma exosome concentrations differed between healthy controls, patients with immunocompetent pulmonary granulomas and patients with lung cancer even after chemotherapy (p < 0.001). Lung cancer patients after chemotherapy had lower exosome concentrations compared to patients with untreated lung cancer or granuloma (p < 0.001 for both). HIV+ patients without lung cancer had significantly higher exosome concentrations compared to HIV+ patients with lung cancer (p = 0.016). Although exosome concentrations differed between all different lung cancer histologies and healthy controls (p < 0.001 for all histologies), adjusted statistical significance was oµy retained for patients with granulomas and SCLC (Small-cell lung cancer, p < 0.001). HIV-induced immunodeficient patients with or without lung cancer had lower plasma exosomes compared to immunocompetent granuloma and lung cancer patients (p < 0.001). Finally, higher plasma exosomes were associated both on univariate (p = 0.044), and multivariate analysis (p = 0.040) with a better 3-year survival in stage II and III NSCLC (Non-small-cell lung carcinoma) patients. In conclusion, our study shows that CD9-positive plasma exosomes are associated with both lung cancer and HIV, prior chemotherapy, as well as with survival, suggesting a possible prognostic value.

Detection of Promoter DNA Methylation in Urine and Plasma Aids the Detection of Non-Small Cell Lung Cancer

PURPOSE

Low-dose CT screening can reduce lung cancer-related mortality. However, CT screening has an FDR of nearly 96%. We sought to assess whether urine samples can be a source for DNA methylation-based detection of non-small cell lung cancer (NSCLC).

EXPERIMENTAL DESIGN

This nested case-control study of subjects with suspicious nodules on CT imaging obtained plasma and urine samples preoperatively. Cases (n = 74) had pathologic confirmation of NSCLC. Controls (n = 27) had a noncancer diagnosis. We detected promoter methylation in plasma and urine samples using methylation on beads and quantitative methylation-specific real-time PCR for cancer-specific genes (CDO1, TAC1, HOXA7, HOXA9, SOX17, and ZFP42).

RESULTS

DNA methylation at cancer-specific loci was detected in both plasma and urine, and was more frequent in patients with cancer compared with controls for all six genes in plasma and in CDO1, TAC1, HOXA9, and SOX17 in urine. Univariate and multivariate logistic regression analysis showed that methylation detection in each one of six genes in plasma and CDO1, TAC1, HOXA9, and SOX17 in urine were significantly associated with the diagnosis of NSCLC, independent of age, race, and smoking pack-years. When methylation was detected for three or more genes in both plasma and urine, the sensitivity and specificity for lung cancer diagnosis were 73% and 92%, respectively.

CONCLUSIONS

DNA methylation-based biomarkers in plasma and urine could be useful as an adjunct to CT screening to guide decision-making regarding further invasive procedures in patients with pulmonary nodules.

Microwave Thermolysis Reduces Generalized and Social Anxiety in Young Adults With Axillary Hyperhidrosis

BACKGROUND AND OBJECTIVE

Hyperhidrosis (HH) is associated with impairments in quality of life (QOL) and elevated anxiety. Microwave thermolysis is a newer treatment that reduces sweating, yet effects on QOL and emotional symptoms have not been examined. Two treatment sessions are recommended to achieve 80% amelioration of clinical HH. We hypothesized that microwave thermolysis would reduce sweat severity, improve QOL, and reduce anxiety in young adults suffering from axillary HH in a prospective clinical trial.

STUDY DESIGN/MATERIALS AND METHODS

We enrolled 24 young adults (mean age = 23.57 years, 54% female) with elevated scores on the Hyperhidrosis Disease Severity Scale. All participants received one session of microwave thermolysis, and 83% received two sessions. Participants completed measures of sweat severity, QOL, generalized anxiety, social anxiety, social avoidance, and anxious/depressive mood symptoms at baseline; post-first treatment; and following second treatment.

RESULTS

At baseline, all participants had severe sweating; 87.5% had impaired QOL, 75% had elevated social anxiety, 50% with generalized anxiety, 48% with social avoidance, and 38% with anxious/depressed mood. Paired samples t tests indicated significant improvements from baseline to first procedure, including decreased sweating (t(21) = 5.68, P < 0.001), improved QOL (t(23) = 4.97, P < 0.001), and decreased generalized anxiety (t(23) = 8.11, P < 0.001), social anxiety (t(22) = 4.55, P < 0.001), mood symptoms (t(21) = 3.81, P = 0.001), and social avoidance (t(22) = 3.12, P = 0.005). After second treatment, further improvements were noted in sweating (t(18) = 3.28, P = 0.004) and QOL (t(18) = 3.83, P = 0.003), and a marginal trend for generalized anxiety (t(19) = 1.96, P = 0.064).

CONCLUSION

There were significant improvements in sweat severity, skin-specific QOL, generalized anxiety, social anxiety, anxious/depressive symptoms, and social avoidance. The majority of the psychosocial benefit appears to emerge after one treatment of microwave thermolysis, whereas the level of sweat severity and QOL continued to show further improvements after a second treatment. Results would suggest that although two microwave thermolysis sessions are needed for maximal treatment optimization of axillary HH, patients may experience significant benefits in improving psychosocial functioning after just one session. Lasers Surg. Med. © 2020 Wiley Periodicals, Inc.

Epigenetic therapy inhibits metastases by disrupting premetastatic niches

Cancer recurrence after surgery remains an unresolved clinical problem^1-3. Myeloid cells derived from bone marrow contribute to the formation of the premetastatic microenvironment, which is required for disseminating tumour cells to engraft distant sites^4-6. There are currently no effective interventions that prevent the formation of the premetastatic microenvironment^6,7. Here we show that, after surgical removal of primary lung, breast and oesophageal cancers, low-dose adjuvant epigenetic therapy disrupts the premetastatic microenvironment and inhibits both the formation and growth of lung metastases through its selective effect on myeloid-derived suppressor cells (MDSCs). In mouse models of pulmonary metastases, MDSCs are key factors in the formation of the premetastatic microenvironment after resection of primary tumours. Adjuvant epigenetic therapy that uses low-dose DNA methyltransferase and histone deacetylase inhibitors, 5-azacytidine and entinostat, disrupts the premetastatic niche by inhibiting the trafficking of MDSCs through the downregulation of CCR2 and CXCR2, and by promoting MDSC differentiation into a more-interstitial macrophage-like phenotype. A decreased accumulation of MDSCs in the premetastatic lung produces longer periods of disease-free survival and increased overall survival, compared with chemotherapy. Our data demonstrate that, even after removal of the primary tumour, MDSCs contribute to the development of premetastatic niches and settlement of residual tumour cells. A combination of low-dose adjuvant epigenetic modifiers that disrupts this premetastatic microenvironment and inhibits metastases may permit an adjuvant approach to cancer therapy.

Abstract 3308: Urine epigenetic biomarkers for NSCLC diagnosis

Purpose:

The National Lung Cancer Screening Trial showed mortality reduction on patients with NSCLC by the use of Low-dose CT screening. The study exhibits an unreasonably high false positive rate of 96.6%, which can to lead to significant morbidity and mortality from unnecessary tests. This study aim to determine if methylated promoter regions of a panel of genes that are correlated with Non-Small Cell Lung Cancer can be detected in urine from patients with lung cancer versus those without.

Materials and Methods:

We conducted a prospective case-control study recruiting subjects from the Lung Cancer Spore Trial. Urine and pre-operative CT scans were obtained from all patients. We processed the urine using the Methylation on Beads assay to isolate and bisulfite treat circulating DNA and then employed Quantitative Methylation Specific Real-Time PCR to detect promoter methylation status of the genes: CDO1, TAC1, HOXA7, HOXA9, SOX17 and ZFP42. Sensitivity, specificity, PPV and NPV values were calculated for each gene methylation status.

Results:

34 patients were studied, including 23 patients with NSCLC and 11 patients with benign non-cancerous lesions. The sensitivity, specificity, PPV and NPV values for lung cancer detection in urine are shown in Table 1. Sensitivities ranged 43-96%, Specificities 64-91%, PPV 71-100% and NPV 40-67%. Promoter methylation of the gene panel CDO1, TAC1, HOXA7, HOXA9, SOX17 and ZPF42 has a 78% sensitivity, 91% specificity, 95% PPV and 67% NPV for lung cancer detection.

Conclusion:

Our study suggests that urine can provide a highly sensitive and specific non-invasive route for lung cancer detection. These results are very promising and could potentially reduce unnecessary morbidity and mortality in people undergoing screening for NSCLC by use of a non-invasive method that could be more accessible on primary care centers. However, further studies and validation with larger sample sizes and different populations are necessary before its application to clinical practice.

Patients with positive gene methylation from urine samples and its accuracy for NSCLC detection.Cancer (n=23)Cancer (n=23)Control (n=11)Control (n=11)nSensitivitynSpecificityPPVNPVCDO114611919353TAC11565010010058SOX1716704648050HOXA711483737940HOXA910431919143ZPF4222969187167Panel of genes18781919567

Citation Format: Lane Lerner, Lily Zheng, Anastasia Kottorou, Chen Chen, Tomoaki Ito, Kristen Rodgers, Beverly Lee, Robert Winn, Enrico Benedetti, Tza- Huei Wang, Malcolm V. Brock, James G. Herman, Alicia Hulbert. Urine epigenetic biomarkers for NSCLC diagnosis [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 3308.

Early Detection of Lung Cancer Using DNA Promoter Hypermethylation in Plasma and Sputum

Purpose: CT screening can reduce death from lung cancer. We sought to improve the diagnostic accuracy of lung cancer screening using ultrasensitive methods and a lung cancer-specific gene panel to detect DNA methylation in sputum and plasma.Experimental Design: This is a case-control study of subjects with suspicious nodules on CT imaging. Plasma and sputum were obtained preoperatively. Cases (n = 150) had pathologic confirmation of node-negative (stages I and IIA) non-small cell lung cancer. Controls (n = 60) had non-cancer diagnoses. We detected promoter methylation using quantitative methylation-specific real-time PCR and methylation-on-beads for cancer-specific genes (SOX17, TAC1, HOXA7, CDO1, HOXA9, and ZFP42).Results: DNA methylation was detected in plasma and sputum more frequently in people with cancer compared with controls (P < 0.001) for five of six genes. The sensitivity and specificity for lung cancer diagnosis using the best individual genes was 63% to 86% and 75% to 92% in sputum, respectively, and 65% to 76% and 74% to 84% in plasma, respectively. A three-gene combination of the best individual genes has sensitivity and specificity of 98% and 71% using sputum and 93% and 62% using plasma. Area under the receiver operating curve for this panel was 0.89 [95% confidence interval (CI), 0.80-0.98] in sputum and 0.77 (95% CI, 0.68-0.86) in plasma. Independent blinded random forest prediction models combining gene methylation with clinical information correctly predicted lung cancer in 91% of subjects using sputum detection and 85% of subjects using plasma detection.Conclusions: High diagnostic accuracy for early-stage lung cancer can be obtained using methylated promoter detection in sputum or plasma. Clin Cancer Res; 23(8); 1998-2005. ©2016 AACR.

Evolution of Neoantigen Landscape during Immune Checkpoint Blockade in Non-Small Cell Lung Cancer

Immune checkpoint inhibitors have shown significant therapeutic responses against tumors containing increased mutation-associated neoantigen load. We have examined the evolving landscape of tumor neoantigens during the emergence of acquired resistance in patients with non-small cell lung cancer after initial response to immune checkpoint blockade with anti-PD-1 or anti-PD-1/anti-CTLA-4 antibodies. Analyses of matched pretreatment and resistant tumors identified genomic changes resulting in loss of 7 to 18 putative mutation-associated neoantigens in resistant clones. Peptides generated from the eliminated neoantigens elicited clonal T-cell expansion in autologous T-cell cultures, suggesting that they generated functional immune responses. Neoantigen loss occurred through elimination of tumor subclones or through deletion of chromosomal regions containing truncal alterations, and was associated with changes in T-cell receptor clonality. These analyses provide insight into the dynamics of mutational landscapes during immune checkpoint blockade and have implications for the development of immune therapies that target tumor neoantigens.Significance: Acquired resistance to immune checkpoint therapy is being recognized more commonly. This work demonstrates for the first time that acquired resistance to immune checkpoint blockade can arise in association with the evolving landscape of mutations, some of which encode tumor neoantigens recognizable by T cells. These observations imply that widening the breadth of neoantigen reactivity may mitigate the development of acquired resistance. Cancer Discov; 7(3); 264-76. ©2017 AACR.See related commentary by Yang, p. 250This article is highlighted in the In This Issue feature, p. 235.

Abstract 4455: DNA methylation as biomarkers to predict early recurrence of T1-2N0 lung cancer

Purpose: Many patients die of recurrent NSCLC. Current clinical and molecular tests fail to predict patients at high risk for recurrence. We investigated the relationship between gene promoter methylation and recurrence of NSCLC and its prediction accuracy.

Materials and Methods: We prospectively enrolled patients who underwent surgery for T1-2N0 NSCLC. We collected primary tumors, regional lymph nodes (RLN) and mediastinal lymph nodes (MLN). A total of 112 patients were included; cases (n = 39) and controls (n = 73) were defined based on cancer recurrence within 40 months of surgery. Promoter methylation of eight cancer-related genes (CDO1, TAC1, SOX17, p16, CDH13, RASSF1A, APC and MGMT) was obtained by using nanoparticle-based DNA extraction followed by qMSP. Logistic regression analysis adjusted by age, gender, race, tumor size and pack year was used to study the relationship between the gene promoter methylation and the risk of recurrence of NSCLC; machine learning assessed its prediction accuracy.

Results: Cases had significantly higher p16 methylation levels than controls in all three tissue types by univariate and multivariate analysis after adjusting for confounders (age, gender, race, tumor size, smoking history, and other gene methylation levels). SOX17 was significantly methylated among cases in both RLN and MLN samples, and remained significant in MLN after adjusting for confounders. Table 1 shows the prediction accuracy of p16 and SOX17 using tumor tissue alone and combined with RLN and/or MLN. Prediction accuracies were increased after adding biomarkers from lymph nodes.

Conclusion: Increased methylation status in the promoter region of p16 and SOX17 is associated with an increased risk of cancer recurrence among patients with T1-2N0 NSCLC treated with curative resection. Adding molecular analyses of lymph nodes to primary tumor samples significantly increased the diagnostic accuracy of predicting recurrence in these patients. Table 1.Prediction accuracy using tumor and combined with RLN and/or MLN.Tissue SamplesSensitivitySpecificityPPVNPVTumor0.410.840.520.76Tumor+RLN0.680.960.900.84Tumor+MLN0.560.880.710.79Tumor+RLN+MLN0.690.900.790.85

Citation Format: Chen Chen, Andrew Yang, Devlin Danielle, Kristen Rodgers, Peng Huang, Zhihao Lu, Candace Griffin, Beverly Lee, Richard Battafarano, Fenglei Yu, Tza-Huei Wang, Stephen Baylin, James Herman, Alicia Hulbert, Malcolm Brock. DNA methylation as biomarkers to predict early recurrence of T1-2N0 lung cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4455.

An interim analysis of a phase II study using an epigenetic biomarker (CHFR methylation status) to personalize chemotherapy in patients with operable esophageal cancer

76

Background: Preoperative chemoradiotherapy using a platinum plus either a taxane or 5FU results in a pathological complete response rate (pCR) of approximately 25% to 30% in patients with operable esophageal cancer. A predictive biomarker to personalize chemotherapy in an effort to increase pCR would be a significant advance. Checkpoint with forkhead and ring finger domains (CHFR) is an E3 ligase which plays a role in response to mitotic stress. In our retrospective data, hypermethylation and silencing of CHFR, correlates with improved response and prolonged survival following therapy with taxanes. The primary endpoint of this study is to determine if there is a higher pCR rate when CHFR methylation status (MS) is used to decide if patients receive a taxane or 5FU. Methods: All patients presenting to Johns Hopkins with operable T2-T4/N0-N3 esophageal cancer are eligibile. A methylation-specific PCR which demonstrates CHFR MS has been developed by our lab. Methylated (M) patients receive weekly cisplatin (30mg/m2)/paclitaxel (50mg/m2) and unmethylated (U) patients receive previously described regimens of folfox or cisplatin/5FU. All patients receive concurrent radiation. Results: From July 2011 to September 2013, 35 patients have been assessed, 18 U (51%), 14 M (40%) and 3 unknown (9%). Twenty-four patients (22 males and 2 females) have been treated on study (age 48 – 74 years old, median 63.8) with 14 tumors U (58%) and 10 tumors M (42%) respectively. To date, 2/13 U patients (15%) have had a pCR and 3/8 M patients (38%) have had a pCR (p=0.32). Toxicities of each regimen are consistent with previous reports. Conclusions: Trimodality therapy is standard of care for operable esophageal cancer in the United States. Different chemotherapies have been combined with radiation prior to surgery to improve pCR rates but no biomarkers to personalize chemotherapy exist at present. Epigenetic biomarkers such as CHFR MS potentially may be used to decide which patients are more sensitive to taxane based regimens. Accrual to this study is ongoing. Clinical trial information: NCT01372202.

Alterations of immune response of Non-Small Cell Lung Cancer with Azacytidine

Innovative therapies are needed for advanced Non-Small Cell Lung Cancer (NSCLC). We have undertaken a genomics based, hypothesis driving, approach to query an emerging potential that epigenetic therapy may sensitize to immune checkpoint therapy targeting PD-L1/PD-1 interaction. NSCLC cell lines were treated with the DNA hypomethylating agent azacytidine (AZA - Vidaza) and genes and pathways altered were mapped by genome-wide expression and DNA methylation analyses. AZA-induced pathways were analyzed in The Cancer Genome Atlas (TCGA) project by mapping the derived gene signatures in hundreds of lung adeno (LUAD) and squamous cell carcinoma (LUSC) samples. AZA up-regulates genes and pathways related to both innate and adaptive immunity and genes related to immune evasion in a several NSCLC lines. DNA hypermethylation and low expression of IRF7, an interferon transcription factor, tracks with this signature particularly in LUSC. In concert with these events, AZA up-regulates PD-L1 transcripts and protein, a key ligand-mediator of immune tolerance. Analysis of TCGA samples demonstrates that a significant proportion of primary NSCLC have low expression of AZA-induced immune genes, including PD-L1. We hypothesize that epigenetic therapy combined with blockade of immune checkpoints - in particular the PD-1/PD-L1 pathway - may augment response of NSCLC by shifting the balance between immune activation and immune inhibition, particularly in a subset of NSCLC with low expression of these pathways. Our studies define a biomarker strategy for response in a recently initiated trial to examine the potential of epigenetic therapy to sensitize patients with NSCLC to PD-1 immune checkpoint blockade.

Predicting sensitivity to azacytidine in non-small cell cancer lines by absence of activating mutations

e18147

Background: A completed clinical trial has demonstrated activity of a combination of epigenetic therapies: entinostat, a histone deacetylase inhibitor, and azacytidine (AZA), a hypomethylating agent. A plasma-based biomarker assaying methylation status of key gene promoters from circulating DNA was developed. In order to test the relationship of activating mutations to sensitivity to epigenetic therapy, we treated non-small cell lung cancer (NSCLC) lines with AZA and assessed tumor growth in xenografts. Tumor from patients on trial was analyzed for mutational status. Methods: Nine NSCLC lines were treated in vitro for 72 hours with 500 nM AZA and injected to form flank tumors in NOG mice. Four lines contain no activating mutations. Of the five mutant lines, three were KRAS and two were EGFR mutations. Lines with no activating mutations are termed “mutation-negative” for known oncogenic drivers. Growth of mock versus treated tumors was compared over time to determine treatment phenotypes. Lines were grouped into four categories: augmented growth compared to mock, no treatment effect, mild inhibition of tumor growth, and marked inhibition. Seventeen tumors from the clinical trial were analyzed by SNaPshot multiplex PCR. Results: Among mutation negative lines three showed marked tumor growth inhibition and one showed mild inhibition. Among cell lines with activating mutations, one showed mild inhibition, three showed no effect, and one showed augmented tumor growth. Among 17 tumor samples from patients on study, four driver mutations were identified: 3 KRAS and one PTEN mutation. All four patients experienced progressive disease on study. Among thirteen patients with mutation negative tumors, three had stable disease and one had a complete response. Conclusions: The association between driver mutation negative status and treatment outcome in NSCLC cell lines in patients receiving AZA and entinostat merits further exploration. Future trials of epigenetic therapy in NSCLC may benefit from a biomarker enrichment strategy and the data presented here represents a potential way forward.

Human immunodeficiency virus infection as a prognostic factor in surgical patients with non-small cell lung cancer

BACKGROUND

The purpose of this study was to assess the effect of human immunodeficiency virus (HIV) infection on postoperative survival among non-small cell lung cancer (NSCLC) patients.

METHODS

A retrospective cohort study compared 22 HIV-infected lung cancer patients to 2,430 lung cancer patients with HIV-unspecified status who underwent resection at Johns Hopkins Hospital from 1985 to 2009. Subcohort comparative analyses were performed using individual matching methods.

RESULTS

Thirty-day mortality rates did not differ between HIV-infected and HIV-unspecified patients. Survival rates for HIV-infected lung cancer patients were significantly shorter than for HIV-unspecified patients (median, 26 versus 48 months; p=0.001). After adjustment, the relative hazard of mortality among HIV-infected NSCLC patients was more than threefold that of HIV-unspecified patients (adjusted hazard ratio, 3.08; 95% confidence interval: 1.85 to 5.13). When additional surgical characteristics were modeled in a matched subcohort, the association remained statistically significant (adjusted hazard ratio, 2.31; 95% confidence interval: 1.11 to 4.81). Moreover, HIV-infected lung cancer patients with CD4 counts less than 200 cells/mm3 had shortened median survival compared with patients whose CD4 counts were 200 cells/mm3 or greater (8 versus 40 months; p=0.031). Postoperative pulmonary and infectious complications were also elevated in the HIV-infected group (p=0.001 and p<0.001, respectively). After surgery, median time to cancer progression was shorter among HIV-infected patients (20.4 months) versus HIV-unspecified patients (p=0.061).

CONCLUSIONS

The HIV-infected NSCLC patients have more postoperative complications, rapid progression to disease recurrence, and poorer postoperative survival. Optimizing immune status before surgery and careful patient selection based on diffusion capacity of lung for carbon monoxide may improve patient outcomes.

Combination epigenetic therapy has efficacy in patients with refractory advanced non-small cell lung cancer

Epigenetic alterations are strongly associated with the development of cancer. We conducted a phase I/II trial of combined epigenetic therapy with azacitidine and entinostat, inhibitors of DNA methylation and histone deacetylation, respectively, in extensively pretreated patients with recurrent metastatic non-small cell lung cancer. This therapy is well tolerated, and objective responses were observed, including a complete response and a partial response in a patient who remains alive and without disease progression approximately 2 years after completing protocol therapy. Median survival in the entire cohort was 6.4 months (95% CI 3.8-9.2), comparing favorably with existing therapeutic options. Demethylation of a set of 4 epigenetically silenced genes known to be associated with lung cancer was detectable in serial blood samples in these patients and was associated with improved progression-free (P = 0.034) and overall survival (P = 0.035). Four of 19 patients had major objective responses to subsequent anticancer therapies given immediately after epigenetic therapy.

SIGNIFICANCE

This study demonstrates that combined epigenetic therapy with low-dose azacitidine and entinostat results in objective, durable responses in patients with solid tumors and defines a blood-based biomarker that correlates with clinical benefit.

Abstract ED03-04: Using epigenetic biomarkers as prognostic and predictive markers in non-small cell lung cancer (NSCLC) and the promise of epigenetic therapy

Epigenetic gene silencing mediated through aberrant DNA methylation and histone deacetylation is a key contributor to lung carcinogenesis. We have defined the utility of a panel of promoter region DNA methylation markers as a robust potential molecular system for re-staging stage 1 non small cell lung cancer (NSCLC) to molecular stage 3 disease. The significance of our finding is that silencing of these gene markers represents not only prognostic markers, but also these genes may serve as potential targets for a unique new epigenetic approach to re-express the silenced genes. We have just completed a phase 2 trial of epigenetic therapy in NSCLC with documented objective responses. The personalization of this therapy with epigenetic biomarkers may make it especially useful for the medically underserved.

Citation Information: Cancer Epidemiol Biomarkers Prev 2011;20(10 Suppl):ED03-04.

Lipoxins: update and impact of endogenous pro-resolution lipid mediators

Lipoxins (LXs) are endogenously produced eicosanoids that are typically generated by transcellular biosynthesis. These trihydroxytetraene-containing lipid mediators and their stable synthetic analogues possess a wide spectrum of anti-inflammatory and pro-resolution bioactions both in vitro and in vivo. More recently, LXs have emerged as potential anti-fibrotic mediators that may influence pro-fibrotic cytokines and matrix-associated gene expression in response to platelet-derived growth factor (PDGF). Here we review the biosynthesis, metabolism and bioactions of LXs and LX analogues and their therapeutic potential.

Rapid fabrication of microfluidic devices in poly(dimethylsiloxane) by photocopying

A very simple and fast method for the fabrication of poly(dimethylsiloxane) (PDMS) microfluidic devices is introduced. By using a photocopying machine to make a master on transparency instead of using lithographic equipment and photoresist, the fabrication process is greatly simplified and speeded up, requiring less than 1.5 h from design to device. Through SEM characterization, any micro-channel network with a width greater than 50 microm and a depth in the range of 8-14 microm can be made by this method. After sealing to a Pyrex glass plate with micromachined platinum electrodes, a microfluidic device was made and the device was tested in FIA mode with on-chip conductometric detection without using either high voltage or other pumping methods.

Development of angiotensin (1-7) as an agent to accelerate dermal repair

Angiotensin II has been shown to be a potent agent in the acceleration of wound repair. Angiotensin (1-7), a fragment of angiotensin II that is not hypertensive, was found to be comparable to angiotensin II in accelerating dermal healing. This activity was evaluated in four models: rat and diabetic mouse full-thickness excisional wounds; rat random flap; and guinea pig partial thickness thermal injury. In all models, angiotensin (1-7) was comparable to angiotensin II. Angiotensin (1-7) accelerated the closure of wounds in diabetic mice and rats. In diabetic mice the resultant tissue at day 25 after injury was more comparable to normal tissue than the fibrotic scar observed in placebo-treated wounds. In the random flap model, angiotensin (1-7) was comparable to angiotensin II in maintaining flap viability (approximately 82%) and flap survival (40%). Finally, angiotensin (1-7) increased proliferation in the hair follicles at the edge of the wound and site of thermal injury, and the number of patent blood vessels on day 7 after partial thickness thermal injury. These data may be partially explained by the effect of angiotensin II and angiotensin (1-7) on keratinocyte proliferation. While platelet-derived growth factor had no effect on keratinocyte proliferation, angiotensin II and angiotensin (1-7) significantly increased keratinocyte proliferation. These data show that angiotensin(1-7) is comparable to angiotensin II in accelerating skin repair. Furthermore, the hypertensive and wound healing effects can be separated within the family of angiotensin peptides.

Integrin alpha1beta1 and transforming growth factor-beta1 play distinct roles in alport glomerular pathogenesis and serve as dual targets for metabolic therapy

Alport syndrome is a genetic disorder resulting from mutations in type IV collagen genes. The defect results in pathological changes in kidney glomerular and inner-ear basement membranes. In the kidney, progressive glomerulonephritis culminates in tubulointerstitial fibrosis and death. Using gene knockout-mouse models, we demonstrate that two different pathways, one mediated by transforming growth factor (TGF)-beta1 and the other by integrin alpha1beta1, affect Alport glomerular pathogenesis in distinct ways. In Alport mice that are also null for integrin alpha1 expression, expansion of the mesangial matrix and podocyte foot process effacement are attenuated. The novel observation of nonnative laminin isoforms (laminin-2 and/or laminin-4) accumulating in the glomerular basement membrane of Alport mice is markedly reduced in the double knockouts. The second pathway, mediated by TGF-beta1, was blocked using a soluble fusion protein comprising the extracellular domain of the TGF-beta1 type II receptor. This inhibitor prevents focal thickening of the glomerular basement membrane, but does not prevent effacement of the podocyte foot processes. If both integrin alpha1beta1 and TGF-beta1 pathways are functionally inhibited, glomerular foot process and glomerular basement membrane morphology are primarily restored and renal function is markedly improved. These data suggest that integrin alpha1beta1 and TGF-beta1 may provide useful targets for a dual therapy aimed at slowing disease progression in Alport glomerulonephritis.

Immunolocalisation of BPTI-like serine proteinase inhibitory proteins in mast cells, chondrocytes and intervertebral disc fibrochondrocytes of ovine and bovine connective tissues. An immunohistochemical and biochemical study

A polyclonal anti-bovine pancreatic trypsin inhibitor (BPTI) IgY was raised in chickens immunised with aprotinin. The anti-BPTI IgY was subsequently isolated from egg yolks and purified to homogeneity by affinity chromatography on immobilised aprotinin and by Superose 6 size exclusion fast protein liquid chromatography (FPLC). Immunoblotting with the chicken IgY demonstrated its specificity for BPTI; 3.9 ng BPTI could be detected by this technique. There was no crossreactivity against alpha1-proteinase inhibitor (human and sheep), inter-alpha-trypsin inhibitor (human and sheep), secretory leucocyte proteinase inhibitor or a range of serine proteinase inhibitory proteins (SPIs) isolated from plant sources (soybean and lima bean trypsin inhibitor, potato trypsin and chymotrypsin inhibitors) or serum SPIs (antithrombin-III, alpha2-macroglobulin). Immunoblotting using the anti-BPTI IgY identified the 6- to 12- and 58-kDa forms of endogenous ovine cartilage SPIs in cartilage extracts, confirming the interrelationship of the ovine cartilage SPIs with BPTI. BPTI-domain SPIs were immunolocalised within mast cells of ovine and bovine duodenum, lung and pancreas, and in ovine and bovine bronchial cartilage chondrocytes, chondrocytes of the superficial and intermediate zones of articular cartilage and in the fibrochondrocytes/chondrocytes of the nucleus

Angiotensin II increases host resistance to peritonitis

Studies by other laboratories have shown that angiotensin II (AII) can affect the function of cells which comprise the immune system. In the present study, the effect of AII on the function of peritoneal macrophages and peripheral blood monocytes was assessed. In vitro exposure (4 h prior to assay) of peritoneal macrophages from mice and rats to AII increased the percentage of cells that phagocytosed opsonized yeast and the number of yeast per macrophage. Furthermore, AII increased the respiratory burst capacity of peritoneal macrophages from mice and rats and peripheral blood mononuclear cells from humans. Because of these observations, the effect of AII on host resistance to bacterial infection was assessed. Intraperitoneal administration of AII was shown to increase host resistance (reduced abscess formation) in an animal model of bacterial peritonitis. Studies were then conducted to assess whether parenteral administration of AII, a clinically relevant route, could affect peritoneal host resistance in a manner similar to that observed after peritoneal administration. These studies showed that subcutaneous administration of AII throughout the postinfection interval increased the level of host resistance to bacterial peritonitis. Furthermore, in a study which compared AII and Neupogen, an agent approved for use for the reduction of febrile neutropenia after myeloablative therapy, daily subcutaneous administration of AII reduced abscess size and incidence, whereas Neupogen did not have any therapeutic benefit in this model. These data suggest that AII may be of therapeutic benefit as an immunomodulatory agent.

A new model for experimental tendon adhesions in the chicken

A minimally invasive model using a manual abrader to induce adhesions in the chicken's central digit is described. The flexor synovial sheath and the profundus tendon were abraded with access through small flaps at the level of the proximal and distal phalanges of the avian long toes. The birds were divided into two groups according to the severity of the induced trauma. Group I birds received an abrasion injury and were euthanized to allow biomechanical testing 5 weeks postoperatively. Group II birds had a more severe abrasion and were euthanized similarly and tested 5 weeks after surgery. Results were compared with nonsurgical controls. Long toe function was evaluated weekly by measuring (1) the range of active flexion of each interphalangeal joint, resolved to total angular range; (2) the grasping ability on graded-diameter perches; and (3) the flexion deficit of the long toe. Postmortem biomechanical properties of the adhesions were measured. There was a significant difference between the unoperated controls and abraded digits of both groups in all parameters (p < 0.001). There was, in addition, a marked change in most of the measured parameters between groups I and II. In group I digits the functional and biomechanical deficit was less than group II. In summary, this animal model of long-segment abrasive injury to the tendon and sheath is a simple and reproducible method to generate adhesions and can be used for the evaluation of treatment modalities for adhesion prevention.

Effect of peroxisome proliferator-activated receptor alpha activators on tumor necrosis factor expression in mice during endotoxemia

Inflammatory mediators orchestrate the host immune and metabolic response to acute bacterial infections and mediate the events leading to septic shock. Tumor necrosis factor (TNF) has long been identified as one of the proximal mediators of endotoxin action. Recent studies have implicated peroxisome proliferator-activated receptor alpha (PPARalpha) as a potential target to modulate regulation of the immune response. Since PPARalpha activators, which are hypolipidemic drugs, are being prescribed for a significant population of older patients, it is important to determine the impact of these drugs on the host response to acute inflammation. Therefore, we examined the role of PPARalpha activators on the regulation of TNF expression in a mouse model of endotoxemia. CD-1 mice treated with dietary fenofibrate or Wy-14,643 had fivefold-higher lipopolysaccharide (LPS)-induced TNF plasma levels than LPS-treated control-fed animals. Higher LPS-induced TNF levels in drug-fed animals were reflected physiologically in significantly lower glucose levels in plasma and a significantly lower 50% lethal dose than those in LPS-treated control-fed animals. Utilizing PPARalpha wild-type (WT) and knockout (KO) mice, we showed that the effect of fenofibrate on LPS-induced TNF expression was indeed mediated by PPARalpha. PPARalpha WT mice fed fenofibrate also had a fivefold increase in LPS-induced TNF levels in plasma compared to control-fed animals. However, LPS-induced TNF levels were significantly decreased and glucose levels in plasma were significantly increased in PPARalpha KO mice fed fenofibrate compared to those in control-fed animals. Data from peritoneal macrophage studies indicate that Wy-14,643 modestly decreased TNF expression in vitro. Similarly, overexpression of PPARalpha in 293T cells decreased activity of a human TNF promoter-luciferase construct. The results from these studies suggest that any anti-inflammatory activity of PPARalpha in vivo can be masked by other systemic effects of PPARalpha activators.

Angiotensin II improves random-flap viability in a rat model

Angiotensin II (AII) is a naturally occurring peptide that has been shown to be angiogenic, cause the proliferation of several primary cell types (including endothelial cells), accelerate the repair of dermal injuries, and increase production of growth factors and extracellular matrix. The effect of a single administration of AII on the viability and vascularity of a random flap was assessed in a rat model. In the control model, the viability of the distal portion of the flap was reduced consistently by postoperative day 8. Initially, AII was administered in an aqueous vehicle (phosphate-buffered saline [PBS]) and a viscous vehicle (10% carboxymethyl cellulose [CMC]). Administration of 1 mg per milliliter AII in PBS did not affect the viability of random flaps (1.2 x 7 cm) in this animal model. However, a single administration of a higher dose of AII in PBS (10 mg per milliliter) or 1 mg per milliliter AII in the CMC vehicle resulted in 67% of the grafts being fully viable at postsurgical day 12, in contrast to vehicle-treated control flaps, none of which were fully viable at day 12. Furthermore, the portion of the flap that was viable was increased significantly (p < or = 0.05). Subsequently, a study was conducted to assess the dose-response curve for AII in a CMC vehicle in this rat model. As the dose of AII was reduced, the percentage of animals with fully viable flaps and the percentage of the flap that was viable decreased correspondingly. Administration of 0.03 mg per milliliter AII and greater increased significantly (p < or = 0.05) the viability of the flaps. In conclusion, AII appears to be highly efficacious in increasing the percentage of distal flap surface area survival when administered as a single topical dose to the wound bed.

Patient and family attitudes regarding the practice of procedures on the newly deceased

Performance of emergency lifesaving procedures is an integral part of emergency medicine resident training.

OBJECTIVE

To assess attitudes of ED patients regarding the practice of procedures on the newly deceased.

METHODS

A descriptive survey was administered to a convenience sample of ED patients and their families at two urban military Level-1 trauma centers. Subjects were asked about their overall opinions regarding the practice of nontherapeutic procedural skills on themselves or relatives immediately after death in the ED. Subgroup analysis included the issue of advanced permission and opinions regarding procedures defined by the investigators as noninvasive (e.g., laryngeal mask airway) or invasive (e.g., cricothyrotomy). Data were analyzed descriptively and with chi-square as appropriate. For comparison of proportions, a sample size of at least 140 was chosen for an alpha of 0.05 and a beta of 0.10 to detect an effect size of 0.3. Alpha was corrected for multiple comparisons prior to the study.

RESULTS

Three hundred seventeen surveys were collected and 88% (n = 280) were complete. Seventy-five percent (n = 290) and 70% (n = 273) of the respondents agreed to after-death procedures on themselves or their relatives, respectively. However, only 40% (n = 106) and 50% (n = 131) would allow such procedures without prior permission. Seventy-one percent (n = 189) were willing to give permission in a living will, while 85% (n = 238) indicated support of a wallet card format. There was no significant difference in permission rates when contrasting individual noninvasive and invasive procedures.

CONCLUSION

Most patients are willing to have procedures performed on themselves or relatives shortly after death, yet the majority request that permission be obtained in advance. A living will or carried card would be acceptable for such permission.

Increased nuchal translucency and CATCH 22

Recent developments in cytogenetics has shown that 22q11 microdeletion is related to a broad spectrum of malformations which are described under the acronym CATCH 22 (Cardiac, Abnormal faces, Thymic hypoplasia, Cleft palate, Hypocalcaemia and 22 chromosome deletion). We describe a case of a fetus with increased nuchal translucency at 12 weeks' gestation presenting with congenital cardiac defects of DiGeorge syndrome type and hypocalcaemia at birth. The neonate was also diagnosed as carrying the 22q11 microdeletion. When nuchal translucency measurement is increased, CATCH 22 spectrum of malformations should be considered and therefore a thorough karyotype analysis should be performed to exclude microdeletion of chromosome 22.

Evaluation of polyethylene glycol/polylactic acid films in the prevention of adhesions in the rabbit adhesion formation and reformation sidewall models

OBJECTIVE

To assess the efficacy of bioresorbable films consisting of various polyethylene glycol 6000 and polylactic acid block copolymers on the formation and reformation of adhesions in rabbit models of adhesion development between the sidewall to the adjacent cecum and bowel. The composition of the different polymers was expressed by the number of monomeric units in the block, namely, ethylene oxide (EO) and lactic acid (LA), respectively.

DESIGN

Studies of the efficacy of EO/LA films were conducted in rabbit sidewall adhesion formation studies in the presence and absence of blood and in rabbit adhesion reformation studies. REPEL (Life Medical Sciences, Edison, NJ), a film of EO/LA ratio 3.0 manufactured under commercial conditions, was also tested in these animal models.

SETTING

University-based laboratory.

ANIMALS

New Zealand white rabbits.

INTERVENTION(S)

Placement of films of various EO/LA ratios at the site of injury to the parietal peritoneum.

MAIN OUTCOME MEASURE(S)

Adhesion formation and reformation.

RESULT(S)

Films of various EO/LA ratios, Seprafilm (Genzyme, Cambridge, MA) and Interceed (Johnson and Johnson Medical, Arlington, TX) placed over an area of excised sidewall at the time of initial injury were highly efficacious in the prevention of adhesion formation. A film of EO/LA ratio 3.7, in contrast with Interceed, was also shown to maintain maximal efficacy in the reduction of adhesion formation in the presence of blood. Further, a film of EO/LA ratio 3.0 produced under commercial conditions, REPEL, was highly efficacious in reducing adhesion development in the rabbit models of adhesion and reformation.

CONCLUSION(S)

These studies suggest that bioresorbable EO/LA films reduced adhesion development in rabbit models of adhesion formation and reformation.

Effect of administration of malathion for 90 days on macrophage function and mast cell degranulation

Previous studies have shown that acute, oral administration of malathion modulated the humoral immune response to T cell-dependent antigen, mitogenic responses, macrophage function and mast cell degranulation. In this report, the effects of malathion administration for 90 days on macrophage function, as measured by respiratory burst capacity, phagocytic capability and the production of cathepsin D, and mast cell integrity were assessed. A dose-dependent increase in respiratory burst activity was observed at all doses tested. The production of cathepsin D was elevated at doses of 1 mg/kg/day malathion or greater. The phagocytic capability of peritoneal macrophages was elevated at the dose of 0.1 mg/kg/day, but was suppressed at higher doses. The effect of oral administration of malathion for 90 days on the degranulation of mast cells, in both organs (skin and uterus) and peritoneal lavage fluid, was also assessed. Degranulation (both severe and slight) of mast cells from the skin and peritoneum was observed at a dose of 1.0 mg/kg/day or greater. In addition, the percentage of mast cells that were undegranulated was decreased. In the skin, but not the peritoneum, these effects were dose-dependent. In the uterus, the percentage of mast cells that were undegranulated was decreased and severely degranulated was increased at a dose of 0.1 mg/kg/day or greater. These data indicate that repeated administration of malathion increased macrophage function and led to mast cell degranulation at doses as low as 0.1 mg/kg/day for 90 days.

Effect of acute administration of malathion by oral and dermal routes on serum histamine levels

Previous studies have shown that acute, oral administration of malathion increased the generation of a humoral immune response, stimulated macrophage function and caused mast cell degranulation and histamine release. In this study, the effect of acute administration of various doses of malathion via oral and dermal routes to mice and rats on serum levels of histamine was evaluated. Oral administration of malathion to mice led to an increase in the level of serum histamine 4 and 8 h after administration. At 4 h after administration, the peak in serum histamine levels was observed at a dose of 10 mg/kg malathion. At 8 h, a maximal effect was observed at a dose of 700 mg/kg and the response was more prolonged than at lower doses. At 12 and 24 h after administration, the level of histamine in the serum of treated mice was comparable to controls. A similar pattern was observed in rats. However, the time point at which histamine levels returned to control was 8 rather than 12 h. After application of malathion to the skin of mice or rats in dimethyl sulphoxide (DMSO), the level of histamine in the blood was also increased. As before, the peak increase was observed at 4 h after administration and the level had returned to control levels within 8 h (slight increase at 8 h in rats) after application. However, after dermal application the maximal levels of histamine in the serum were noted at the highest doses of malathion. The no effect levels for histamine in the blood after malathion administration to these two species by these two routes are as follows: (1) Mice, oral in corn oil, 0.1 mg/kg; (2) Rats, oral in corn oil, 0.1 mg/kg; (3) Mice, dermal in DMSO, 2 mg/kg; (4) Rats, dermal in DMSO--not determined (2 mg/kg low effect level).

Effects of malathion metabolites on degranulation of and mediator release by human and rat basophilic cells

In the present study, the effects of malathion and malathion derivatives on histamine and beta-hexosaminidase release by RBL-1 cells, rat peritoneal mast cells (RPMC), and human peripheral blood basophils (HPBB) and cutaneous mast calls were examined. One hour of incubation of RBL-1 cells with all organophosphate compounds tested, except for malathion and malathion monoacid, led to an increase in histamine release. beta-Hexosaminidase, an enzyme released by basophilic cells and a biochemical marker of degranulation, was not released from RBL-1 cells after 1 h of exposure to organophosphate compounds. Within 4 h, all compounds tested increased the release of histamine and beta-hexosaminidase. Longer exposures led to a decrease in the concentration of the compound that was required to cause mediator release. Exposure of RPMC to organophosphate compounds, with the exception of malathion monoacid and malathion (30 min) or malathion monoacid (1 h), led to the release of histamine, but not beta-hexosaminidase. Incubation of HPBB with malaoxon (51.4 +/- 2.8% total histamine released), malathion diacid (25.7 +/- 2.9%), beta-malathion monoacid (31.4 +/- 2.8%), and isomalathion (57.1 +/- 17.1%) for 1 h led to the release of histamine. Only malaoxon and isomalathion caused beta-hexosaminidase release from HPBB after a 1-h incubation. Incubation of cutaneous mast cells with malaoxon and beta-monoacid for 4 h led to increased release of histamine and beta-hexosaminidase at levels comparable to compound 48/80. These data suggest that malathion metabolites can cause rapid release of histamine from basophilic cells from a variety of origins and species. With prolonged incubation, malathion itself caused the release of mast-cell mediators, suggesting that the cells may be capable of metabolizing malathion. These data also indicate a disparity between the release kinetics of two different mast-cell mediators contained in granules by organophosphates, and that there are different mechanisms of mediator release.

Effect of administration of malathion for 14 days on macrophage function and mast cell degranulation

Previous studies have shown that acute, oral administration of malathion modulated the humoral immune response to T-cell-dependent antigen, mitogenic responses, macrophage function, and mast cell degranulation. While administration of malathion for 14 days did not affect the generation of an immune response to antigen, it was possible that macrophage and mast cell functions were affected. In this report, the effect of malathion administration for 14 days upon these parameters were assessed. This treatment regimen increased the respiratory burst capacity to a maximal level at a dose of 1 mg/kg/day or greater. The effect of oral administration of malathion for 14 days on the degranulation of mast cells in various organs (heart, skin, and small intestine) and peritoneal lavage fluid was also assessed. At doses of 1 mg/kg/day and above, the number of mast cells that was undegranulated decreased and the number that was severely degranulated increased. There was no change in mast cell integrity in biopsies from heart and skin, and in peritoneal fluid after 14-day administration of 0.1 mg/kg/day. However, the number of mast cells associated with the small intestine that had undergone degranulation was increased at this dose of malathion. These data indicate that repeated administration of malathion increased macrophage function at doses as low as 1 mg/kg/day and led to mast cell degranulation at doses as low as 0.1 mg/kg/day.

[Animal models used for the evaluation of anti-osteoarthritis drugs]

Naturally occurring osteoarthritis occurs in a variety of animal species including mice, guinea pigs, dogs and cynomolgus macaques and some of these animals have been used to evaluate the ability of anti-osteoarthritis drugs to reduce synovial inflammation and preserve cartilage integrity. However, the genetically determined animal models of osteoarthritis require the establishment of colonies which may take several years to develop and may be influenced by the strain of animal used and ill-defined environmental factors. On the other hand, the injection of irritants or enzymes into joints, or destabilization by surgical means, can rapidly and reproducibly lead to joint arthropathy and has therefore been more widely used. Although small animals, particularly rats and rabbits, have been the favoured target species, large animals such as dogs and sheep offer many advantages including the opportunity to undertake topographical analysis of joint cartilage and serial aspiration of synovial fluid. Meniscectomy is a common orthopaedic procedure which, in man and animals, is known to lead to osteoarthritis. In the past we have used this technique to induce osteoarthritis in pure bred dogs but more recently we have employed pure bred Merino sheep, which were matched for age, sex and weight. Using this ovine model we have been able to monitor the early and intermediate stages of cartilage metabolism, as well as identify key proteinases responsible for the loss of proteoglycans from these tissues in osteoarthritis. The effects of anti-osteoarthritis drugs on inflammatory mediators and cartilage metabolism has been successfully studied using the ovine model of osteoarthritis.

Acceleration of dermal tissue repair by angiotensin II

Angiotensin II is a naturally occurring peptide which has been shown to possess angiogenic properties. In the studies reported here, angiotensin II was shown to increase the proliferation of cultured bovine aortic arch endothelial cells in a concentration-dependent manner. Acute administration of angiotensin II in Hydron accelerated the repair of dermal injuries in a full-thickness excisional rat model. Additional studies were done to determine the best vehicle for delivery of angiotensin II to a dermal injury. Several vehicles, including 10% low-viscosity carboxymethyl cellulose, 4% medium-viscosity carboxymethyl cellulose, and 3% high-viscosity carboxymethyl cellulose, were found to be effective in this regard. Daily administration of angiotensin II for days 0 to 4 after injury (day 0 being the time of surgery) was determined to provide the optimal dosage for acceleration of wound repair by angiotensin II. In addition, dose-response studies indicated that angiotensin II accelerated wound repair in a dose-dependent fashion with 0.03 and 0.01 microg/rat/day of angiotensin II administered on days 0 to 4 being the minimally effective and no-effect doses, respectively. Administration of 100 microg/day of angiotensin II in 10% carboxymethyl cellulose for 5 days after injury to animals with impaired healing (steroid- and adriamycin-treated rats and diabetic mice) was also found to accelerate the rate of repair. In conclusion, angiotensin II accelerated the closure of full-thickness skin injuries in a dose-dependent manner in normal and impaired animal models.

Immunotoxicity of medical devices. Symposium overview

Determination of the ability of a medical device to interact with the immune system currently involves assessment of the immunogenic potential and biocompatibility of the device or an extract of the device. However, implants are often in the body for extended periods of time and/or are placed by a surgical procedure that in and of itself will generate an acute inflammatory response. This symposium discussed studies that have been performed to evaluate the immunogenicity of various devices consisting of several different compositions (i.e., silicone, metals, and latex) in contact with different anatomical sites, the ability of a device to modulate an inflammatory response generated by a surgical procedure or trauma, and the response of the body to a material left in place for extended periods of time. This symposium brought together scientists from many different disciplines to begin to identify and fill in the gaps in this area.