[Association between serum lysophosphatidylcholine level and elderly health index in older people from longevity areas of Guangxi Province]

Objective: To investigate the relationship between serum lysophosphatidylcholine (LPC) level and the health index of the elderly. Methods: A total of 251 subjects were selected from the 2016 baseline survey of the Yongfu Longevity Cohort in Guangxi Province among whom 66, 63 and 122 were in the young and middle-aged group (≤59 years old), the young group (60-89 years old) and the longevity group (≥90 years old), respectively. Demographic data were collected and related indicators of height, weight, blood pressure and lipid metabolism were measured. The cognitive and physical functions of the elderly were assessed by the results of the simple mental state scale and the daily living activity scale to construct the health index of the elderly. The serum levels of LPC16∶0, LPC18∶0, LPC18∶1 and LPC18∶2 were determined by liquid chromatography-tandem mass spectrometry, and the differences among different ages and health status groups were compared. The logistic regression model was used to analyze the relationship between the serum LPC level and the health index of the elderly. Results: With the increase in age, the proportion of female subjects increased, and the rate of smoking and drinking decreased. BMI, TC, TG, LDL-C, diastolic blood pressure, and the four LPCs levels decreased with the increase of age, and systolic blood pressure levels increased with the increase of age (all P values<0.05). There was no significant difference in HDL-C levels among age groups (P>0.05). With the decline of health status in the elderly, serum levels of LPC16∶0, LPC18∶0, LPC18∶1 and LPC18∶2 showed a downward trend (all P values<0.001). After adjusting for age and gender, only LPC18∶0 was associated with the health status in old age [OR (95%CI): 0.48 (0.25-0.92)]. For every 1 standard deviation (16.87 nmol/L) increase in serum LPC18∶0 concentration, the risk of poor health status in old age decreased by 52%. Conclusion: Serum LPC18∶0 was associated with the health status in old age independent of age and sex.

[Research progress on main disease-related factors of healthy life expectancy]

International research on healthy life expectancy (HALE) focuses on inequality of socioeconomic status and individual natural attributes. With the acceleration of population ageing and the increase in average life expectancy, the extension of unhealthy life expectancy and the increase of social and economic burden caused by diseases have gradually attracted the attention of countries around the world. Therefore, the evaluation of disease factors affecting HALE is a meaningful direction in the future. This study introduces the development process and commonly used measurement methods of HALE. According to the definition of health from the Global Burden of Disease Study and World Health Organization, physical and mental diseases such as cardiovascular and cerebrovascular diseases, chronic respiratory diseases, diabetes, malignant tumors and depression were selected to summarize the impact of these diseases and pre-disease states on HALE. It is expected to provide a theoretical basis for the formulation of relevant public health policies and the improvement of quality of life in China.

Pembrolizumab and cabozantinib in recurrent metastatic head and neck squamous cell carcinoma: a phase 2 trial

Anti-programmed cell death protein 1 (PD-1) therapy is a standard of care in recurrent metastatic head and neck squamous cell carcinoma (RMHNSCC). Vascular endothelial growth factor inhibitors, including tyrosine kinase inhibitors, have immunomodulatory properties and have offered promising results when combined with anti-PD-1 agents. We conducted a phase 2, multicenter, single-arm trial of pembrolizumab and cabozantinib in patients with RMHNSCC who had Response Evaluation Criteria in Solid Tumors v.1.1 measurable disease and no contraindications to either agent. We assessed the primary end points of tolerability and overall response rate to the combination with secondary end points of progression-free survival and overall survival and performed correlative studies with PDL-1 and combined positive score, CD8+ T cell infiltration and tumor mutational burden. A total of 50 patients were screened and 36 were enrolled with 33 evaluable for response. The primary end point was met, with 17 out of 33 patients having a partial response (52%) and 13 (39%) stable disease with an overall clinical benefit rate of 91%. Median and 1-year overall survival were 22.3 months (95% confidence interval (CI) = 11.7-32.9) and 68.4% (95% CI = 45.1%-83.5%), respectively. Median and 1-year progression-free survival were 14.6 months (95% CI = 8.2-19.6) and 54% (95% CI = 31.5%-72%), respectively. Grade 3 or higher treatment-related adverse events included increased aspartate aminotransferase (n = 2, 5.6%). In 16 patients (44.4%), the dose of cabozantinib was reduced to 20 mg daily. The overall response rate correlated positively with baseline CD8+ T cell infiltration. There was no observed correlation between tumor mutational burden and clinical outcome. Pembrolizumab and cabozantinib were well tolerated and showed promising clinical activity in patients with RMHNSCC. Further investigation of similar combinations are needed in RMHNSCC. The trial is registered at ClinicalTrials.gov under registration no. NCT03468218 .

Comparison of the Seventh and Eighth Edition of American Joint Committee on Cancer (AJCC) Staging for Selected and Nonselected Oropharyngeal Squamous Cell Carcinomas

OBJECTIVES

The eighth edition American Joint Committee on Cancer (AJCC) Staging incorporates significant changes to the seventh edition in the staging of oropharyngeal squamous cell carcinomas (OPSCC). An important change was the inclusion of OPSCC associated with the human papilloma virus (HPV). Our goal is to compare the performance of both staging systems for patients with HPV-selected and unselected clinical characteristics for OPSCC.

METHODS

Using the Surveillance, Epidemiology, and End Results (SEER) database, 2004-2016, we identified patients with likely HPV-associated OPSCC based on surrogate markers (white males aged <65 years old with squamous cell carcinomas of the tonsil and base of tongue), excluding those who underwent surgery. We re-classified these patients using seventh and eighth edition staging for HPV-selected OPSCC and compared the prediction performance of both staging editions for overall survival (OS) and disease-specific survival (DSS). We performed the same analysis for clinically unselected patients with OPSCC.

RESULTS

Our analysis included 9554 patients with a median follow-up of 67 months. Comparing the eighth versus seventh edition for our HPV-selected cohort, clinical staging changed for 92.3% of patients and 10-year OS was 62.2%, 61.2%, 35.3%, and 15.5% for Stage I, II, III, and IV, versus 52.9%, 59.2%, 61.6%, 55.1%, 38.3%, and 15.5% for stage I, II, III, IVA, IVB, and IVC, respectively. A similar pattern was observed for 10-year DSS. The concordance statistics for our HPV-selected cohort were improved for both AJCC 7 (0.6260) and AJCC 8 (0.6846) compared with the unselected cohort, 0.5860 and 0.6457 for AJCC 7 and 8, respectively.

CONCLUSION

The overall performance of discrimination improved from AJCC 7 to AJCC 8 for both clinically selected and unselected patients, but more notably for our HPV-selected cohort. Despite the lack of statistically significant differentiation between Stages I and II in AJCC 8 in either groups, markedly improved discrimination was observed between Stages I/II, III, and IV in the HPV-selected cohort.

Cisplatin-mediated activation of glucocorticoid receptor induces platinum resistance via MAST1

Agonists of glucocorticoid receptor (GR) are frequently given to cancer patients with platinum-containing chemotherapy to reduce inflammation, but how GR influences tumor growth in response to platinum-based chemotherapy such as cisplatin through inflammation-independent signaling remains largely unclear. Combined genomics and transcription factor profiling reveal that MAST1, a critical platinum resistance factor that reprograms the MAPK pathway, is upregulated upon cisplatin exposure through activated transcription factor GR. Mechanistically, cisplatin binds to C622 in GR and recruits GR to the nucleus for its activation, which induces MAST1 expression and consequently reactivates MEK signaling. GR nuclear translocation and MAST1 upregulation coordinately occur in patient tumors collected after platinum treatment, and align with patient treatment resistance. Co-treatment with dexamethasone and cisplatin restores cisplatin-resistant tumor growth, whereas addition of the MAST1 inhibitor lestaurtinib abrogates tumor growth while preserving the inhibitory effect of dexamethasone on inflammation in vivo. These findings not only provide insights into the underlying mechanism of GR in cisplatin resistance but also offer an effective alternative therapeutic strategy to improve the clinical outcome of patients receiving platinum-based chemotherapy with GR agonists.

[Association between pulse pressure and new-onset diabetes in hypertensive patients]

Objective: To determine the association between pulse pressure and the risk of new-onset diabetes in hypertensive patients. Methods: In this prospective cohort study, hypertensive patients from the Kailuan Study, who were diagnosed in 2006-2007 check-up, were screened for enrollment. Participants who finished the biennial follow-up until December 31, 2017 were finally included in this analysis. The primary outcome was incident diabetes development. The pulse pressure variables were divided into quartiles (Q1-Q4), and the Kaplan-Meier curve was used to examine and estimate the cumulative incidence of new-onset diabetes among quartiles. Cox proportional hazards regression model was performed to explore the association between pulse pressure and the risk of new-onset diabetes in hypertensive patients. Results: During an average follow-up of 8.17 years, 6 617 new-onset diabetes were identified out of the 32 917 hypertensive patients with no history or evidence of diabetes in 2006-2007 check-up. Participants were classified into quartiles according to pulse pressure levels as follows: Q1 group(<41 mmHg (1mmHg=0.133kPa))(n=7 995); Q2 group(41-<51 mmHg) (n=8 196); Q3 group (51-<61 mmHg) (n= 8 270); Q4 group (≥61 mmHg) (n=8 456). The cumulative incidences of new-onset diabetes across the quartiles were 16.94%, 19.61%, 21.07%, and 22.33%, respectively, with the incidence density was 20.27, 23.20, 24.92, and 26.10 per 1 000 person-years, respectively. The cumulative incidence of new-onset diabetes increased in proportion with increasing pulse pressure levels (P<0.01 by the Log-rank test). After multivariate adjustment, compared with the first quartile, the hazard ratios for new-onset diabetes in the third and fourth quartiles were 1.13 (95%CI 1.04-1.22, P<0.01) and 1.14 (95%CI 1.05-1.24, P<0.01), respectively. The risk of new-onset diabetes increased 5%(HR=1.05, 95%CI 1.02-1.08, P<0.01) with the fractional pulse pressure increased per 1 SD (0.13). Findings from the three sensitivity analyses were consistent with the main results in this cohort. Conclusions: Pulse pressure at baseline is positively associated with the incidence of new-onset diabetes among hypertensive individuals, and pulse pressure is an independent risk factor for the development of diabetes in hypertensive patients.

Machine Learning-Based Prediction of Small Intracranial Aneurysm Rupture Status Using CTA-Derived Hemodynamics: A Multicenter Study

BACKGROUND AND PURPOSE

Small intracranial aneurysms are being increasingly detected while the rupture risk is not well-understood. We aimed to develop rupture-risk models of small aneurysms by combining clinical, morphologic, and hemodynamic information based on machine learning techniques and to test the models in external validation datasets.

MATERIALS AND METHODS

From January 2010 to December 2016, five hundred four consecutive patients with only small aneurysms (<5 mm) detected by CTA and invasive cerebral angiography (or surgery) were retrospectively enrolled and randomly split into training (81%) and internal validation (19%) sets to derive and validate the proposed machine learning models (support vector machine, random forest, logistic regression, and multilayer perceptron). Hemodynamic parameters were obtained using computational fluid dynamics simulation. External validation was performed in other hospitals to test the models.

RESULTS

The support vector machine performed the best with areas under the curve of 0.88 (95% CI, 0.85-0.92) and 0.91 (95% CI, 0.74-0.98) in the training and internal validation datasets, respectively. Feature ranks suggested hemodynamic parameters, including stable flow pattern, concentrated inflow streams, and a small (<50%) flow-impingement zone, and the oscillatory shear index coefficient of variation, were the best predictors of aneurysm rupture. The support vector machine showed an area under the curve of 0.82 (95% CI, 0.69-0.94) in the external validation dataset, and no significant difference was found for the areas under the curve between internal and external validation datasets (P = .21).

CONCLUSIONS

This study revealed that machine learning had a good performance in predicting the rupture status of small aneurysms in both internal and external datasets. Aneurysm hemodynamic parameters were regarded as the most important predictors.

Veno-venous extracorporeal membrane oxygenation successfully treated a case of severe pulmonary hemorrhage caused by leptospirosis

BACKGROUND

Pulmonary hemorrhage is an important complication of leptospirosis. Once acute respiratory distress syndrome (ARDS) occurs as a secondary condition, treatment is extremely difficult and the mortality rate is very high.

CASE PRESENTATION

The patient was a 49-year-old. He was admitted to the hospital because he had experienced a fever and cough for 4 days. Hemorrhage, respiratory failure, ARDS and other symptoms appeared soon after admission. Due to severe pulmonary hemorrhage secondary to ARDS, mechanical ventilation was performed through tracheal intubation. During intubation, the patient suffered cardiac arrest, and the patient's condition worsened. He was confirmed to have leptospirosis through second-generation sequencing of the alveolar lavage fluid. Finally, we successfully treated the patient with penicillin as an anti-infective medication and venous-venous extracorporeal membrane oxygenation (v-vECMO). To the best of our knowledge, this report is the first to describe the successful application of ECMO in mainland China.

CONCLUSIONS

Leptospirosis can induce serious but transient ARDS with a better prognosis than other causes of ARDS. Our patient was successfully treated with V-vECMO.

Abstract 2980: Effects of cetuximab and CD-3379 on cytokine/chemokine balance in the tumor micro-environment (TME) of squamous cell carcinoma of the head and neck (SCCHN)

Background: The Anti-EGFR agent cetuximab has shown promising outcomes and remains to be the only FDA-approved non-immunotherapeutic targeted agent for the treatment of squamous cell carcinoma of the head and neck (SCCHN). There is evidence that immune modulation represents a mechanism by which cetuximab elicits its clinical activity in SCCHN. As resistance inevitably occurs to cetuximab, there is a need to further elucidate the biological mechanisms by which cetuximab affects immune effectors in the tumor microenvironment (TME). We aimed to explore the effect of EGFR inhibition on the cytokine/chemokine balance in the TME.

Methods: Three SCCHN cancer cell lines UM-SCC47 (HPV positive), JHU022 (HPV negative), and SCC-1C (HPV negative and resistant to cetuximab) were treated with cetuximab, CD-3379 (a HER3 inhibitor), and their combination. After 48 and/or 72 hours, the supernatants of the treated and untreated cells were collected and subjected to multiplexed immunoassay [Meso Scale Discovery (MSD) U-PLEX Assays] to study the cytokine/chemokine alteration. Changes in immune suppressive chemokines were confirmed by ELISA. A potential effect of a chemokine neutralizing antibody on apoptosis was further evaluated using patient-derived organotypic cancer spheroids (PDOCSs).

Results: Our results identified 10 down regulated cytokines/chemokines, including IL6, IL-8, IL-2, IL-12, IL-27, IL-4, IL-5, TGF-β, GM-CSF, and IFN-γ in at least one SCCHN cell line. Three cytokines/chemokines were up regulated, including IL-15, MCP-3, and MCP-1. MCP-1 (CCL2) is a modulator of myeloid-derived suppressor cells (MDSCs). Enhancing MCP-1 by cetuximab and/or CD-3379 in the SCCHN cell lines was confirmed by ELISA. Treating multiple PDOCSs with the same combination along with MCP-1 neutralizing antibody enhanced apoptosis in comparison to cetuximab, CD-3379, or the cetuximab/CD-3379 combination.

Conclusions: Our findings suggest that cetuximab in combination with HER3 inhibition affects secretion of cytokines/chemokines which are both immune stimulatory and suppressive in the TME of SCCHN. Alteration of the selected cytokines/chemokines may enhance the clinical activity of EGFR targeting in SCCHN.

Citation Format: Dongsheng Wang, Sreenivas Nannapaneni, Gregory B. Lesinski, Dong M. Shin, Nabil F. Saba, Georgia Z. Chen. Effects of cetuximab and CD-3379 on cytokine/chemokine balance in the tumor micro-environment (TME) of squamous cell carcinoma of the head and neck (SCCHN) [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 2980.

Demographic and Socioeconomic Factors Associated With Metastases at Presentation in HPV-Related Squamous Cell Carcinoma of the Head and Neck: An NCDB Analysis

PURPOSE

Human papillomavirus (HPV)-related squamous cell carcinomas of the head and neck (SCCHNs) tend to have a distinct prognosis. Socioeconomic and demographic factors associated with metastatic disease at presentation and diagnosis in patients with HPV-related SCCHN tumors were examined.

METHODS

The National Cancer Database (NCDB) was queried to assess patients with HPV-related oropharyngeal carcinomas (HPVOPCAs) and HPV-related nonoropharyngeal carcinomas (HPVNOPCAs) diagnosed between 2010 and 2014. Rate of metastases at presentation was analyzed using clinical M stage. Multivariable analysis was performed evaluating race, ethnicity, sex, age, facility location, facility type, insurance status, income, education, and tumor and nodal stage using logistic regression.

RESULTS

A total of 12,857 patients with HPVOPCA and 952 patients with HPVNOPCA were included. Private insurance was carried by 64% and 47% of patients with HPVOPCA and HPVNOPCA, respectively. HPVOPCA was located in the tonsil in 56% of patients. For both HPVOPCA and HPVNOPCA, there was no meaningful difference in distant metastasis at presentation based on facility type or location, sex, race, Hispanic ethnicity, or urban or rural location. For HPVOPCA, there were significantly lower odds of metastasis in privately insured patients compared with uninsured patients (odds ratio [OR], 0.37; 95% CI, 0.21 to 0.64; P < .001) and higher odds of metastasis for patients living in census tracts with the lowest rates of high school graduates compared with the highest rates (OR, 1.81; 95% CI, 1.02 to 3.19; P = .041) and for patients with higher tumor stage (OR, 3.67, 95% CI, 2.25 to 5.99; P < .001) and nodal stage (OR, 3.34; 95% CI, 2.11 to 5.29; P < .001). For HPVNOPCA, neither higher T or N stage nor any demographic features were found to be associated with metastasis at presentation.

CONCLUSION

This large retrospective analysis identifies likely modifiable risk factors for metastatic presentation in HPVOPCA. Educational interventions may result in modifications of these patterns.

Abstract 4834: Effective treatment of squamous cell carcinoma of the head and neck (HNSCC) using a combined regimen of tipifarnib and cetuximab

Background: H-RAS driven carcinogenesis has been reported in many types of cancer including squamous cell carcinoma of the head and neck (HNSCC). The mutation rate of H-RAS in HNSCC is 4 - 8%. Tipifarnib is a potent and highly selective inhibitor of farnesyltransferase (FT). It is known that H-RAS, but not K-RAS and N-RAS, is delocalized into cytoplasm and inactivated by farnesyltransferase inhibitors (FTI), such as tipifarnib. Tipifarnib has demonstrated proof of concept activity in H-RAS mutant HNSCC in an ongoing clinical trial (NCT02383927). In this study, we examined H-RAS associated signaling pathway in HNSCC cell lines and PDX models to see if inhibition of wild-type HRAS signaling could re-sensitize cetuximab resistant cells and tumors to inhibition by cetuximab. UMSCC47 and SCC1-C are both H-RAS wild-type HNSCC cell lines, and SCC1-C is resistant to EGFR targeted therapy.

Methods: In vitro cell growth with and without tipifarnib and/or cetuximab treatments were examined by Sulforhodamine B (SRB) and colony formation assay. Patient derived xenograft (PDX) models were then used to study the efficacy of the tipifarnib treatment as a single agent or in combination with cetuximab. Western blot analyses were performed to verify the effect of these treatments on EGFR/ERK/AKT signaling pathways.

Results: Our results showed that tipifarnib could inhibit HNSCC growth, both in vitro and in the PDX model in a dose-dependent manner (control vs the low dose of tipifarnib, p = 0.02; control vs the high dose of tipifarnib, p = 0.001). However, the combined treatment with cetuximab significantly enhanced tipifarnib efficacy in the H-RAS wild type setting, particularly in the PDX model (control vs tipifarnib, p = 0.123; control vs cetuximab, p = 0.022; control vs the combination, p = 0.010). Western blot analyses showed that neither ERK nor AKT phosphorylation was effectively reduced after a prolonged treatment (48 hours) with tipifarnib alone. However, the addition of cetuximab reduced pERK.

Conclusions: Our study demonstrates that cetuximab enhances the anti-tumor effect of tipifarnib in the H-RAS wild type setting through ERK inhibition. This study supports the rationale for combining tipifarnib with EGFR inhibitors as a possible effective therapeutic approach in HNSCC.

Citation Format: Lihua Shu, Dongsheng Wang, Sreenivas Nannapaneni, Dong M. Shin, Nabil F. Saba, Georgia Z. Chen. Effective treatment of squamous cell carcinoma of the head and neck (HNSCC) using a combined regimen of tipifarnib and cetuximab [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 4834.

Inositol-triphosphate 3-kinase B confers cisplatin resistance by regulating NOX4-dependent redox balance

How altered metabolism contributes to chemotherapy resistance in cancer cells remains unclear. Through a metabolism-related kinome RNAi screen, we identified inositol-trisphosphate 3-kinase B (ITPKB) as a critical enzyme that contributes to cisplatin-resistant tumor growth. We demonstrated that inositol 1,3,4,5-tetrakisphosphate (IP4), the product of ITPKB, plays a critical role in redox homeostasis upon cisplatin exposure by reducing cisplatin-induced ROS through inhibition of a ROS-generating enzyme, NADPH oxidase 4 (NOX4), which promotes cisplatin-resistant tumor growth. Mechanistically, we identified that IP4 competes with the NOX4 cofactor NADPH for binding and consequently inhibits NOX4. Targeting ITPKB with shRNA or its small-molecule inhibitor resulted in attenuation of NOX4 activity, imbalanced redox status, and sensitized cancer cells to cisplatin treatment in patient-derived xenografts. Our findings provide insight into the crosstalk between kinase-mediated metabolic regulation and platinum-based chemotherapy resistance in human cancers. Our study also suggests a distinctive signaling function of IP4 that regulates NOX4. Furthermore, pharmaceutical inhibition of ITPKB displayed synergistic attenuation of tumor growth with cisplatin, suggesting ITPKB as a promising synthetic lethal target for cancer therapeutic intervention to overcome cisplatin resistance.

MAST1 Drives Cisplatin Resistance in Human Cancers by Rewiring cRaf-Independent MEK Activation

Platinum-based chemotherapeutics represent a mainstay of cancer therapy, but resistance limits their curative potential. Through a kinome RNAi screen, we identified microtubule-associated serine/threonine kinase 1 (MAST1) as a main driver of cisplatin resistance in human cancers. Mechanistically, cisplatin but no other DNA-damaging agents inhibit the MAPK pathway by dissociating cRaf from MEK1, while MAST1 replaces cRaf to reactivate the MAPK pathway in a cRaf-independent manner. We show clinical evidence that expression of MAST1, both initial and cisplatin-induced, contributes to platinum resistance and worse clinical outcome. Targeting MAST1 with lestaurtinib, a recently identified MAST1 inhibitor, restores cisplatin sensitivity, leading to the synergistic attenuation of cancer cell proliferation and tumor growth in human cancer cells and patient-derived xenograft models.

[A cohort study on body mass index and risk of all-cause mortality among hypertensive population]

Objective: To investigate the relationship between body mass index (BMI) and all-cause mortality in hypertensive population. Methods: All participants were selected from a prospective cohort study based on a rural population from Henan province, China. Cox proportional hazards regression models were used to estimate the associations of different levels of BMI stratification with all-cause mortality. Restricted cubic spline models were used to detect the dose-response relation. Results: Among the 5 461 hypertensive patients, a total of 31 048.38 person-years follow-up was conducted. The median of follow-up time was 6 years, and 589 deaths occurred during the follow-up period. Compared to normal weight group (18.5 kg/m(2)<BMI<24.0 kg/m(2)) the multivariate-adjusted hazard ratios for all-cause mortality associated with BMI levels (<18.5 kg/m(2), 24-28 kg/m(2), and ≥28 kg/m(2)) were 0.83 (95%CI: 0.37-1.87), 0.81 (95%CI: 0.67-0.97), and 0.72 (95%CI: 0.56-0.91), respectively. The dose-response analysis showed a nonlinear, reverse "S" shaped relationship (non-linearity P<0.001). Conclusion: Overweight or obese might have a protective effect on all-cause mortality in hypertensive population, which supports the "obesity paradox" phenomenon.

[Epidemiology related to soil-borne nematode disease in Danzhou city, Hainan province]

Objective: To understand the prevalence, trend and related factors on soil-borne nematode in Danzhou city to provide information for prevention and control of the disease. Methods: According to the guidelines set by the National National soil-borne nematode technical solutions, one village was randomly chosen from every township as the monitoring location, in the east, west, south and north parts of Danzhou city. A total of 200 residents aged 3 years and over were randomly selected in each monitoring site, with modified Kato thick smear and Cellophane tape anal swab used for microscopy. Results: In this survey, we retrospectively analyzed the rates on soil borne nematode infection in five monitoring locations of Danzhou city and the results showed that the overall positive rates of infection was 19.5% (195/1 000). Comparing with the previous surveys, rates on soil-borne parasites infection were decreasing. The main types of soil-borne nematode infection appeared as roundworm, whipworm, hookworm and pinworm in Danzhou city, with rate of hookworm-egg infection ranking the highest (42.5%, 85/200) in Dacheng. The infection rate was seen significantly higher in females than males. People aged over 60 and between 3-10, had a higher rates of infection. Rate on multiple infections reached 16.9%, including 5 triple infection cases. Conclusion: Rates of infection on soil-borne nematodes in Danzhou city showed a decreasing trend from 2013 to 2016 with hookworm and whipworm as the major ones.

Cerebral CTA with Low Tube Voltage and Low Contrast Material Volume for Detection of Intracranial Aneurysms

BACKGROUND AND PURPOSE

Multidetector row CTA has become the primary imaging technique for detecting intracranial aneurysms. Technical progress enables the use of cerebral CTA with lower radiation doses and contrast media. We evaluated the diagnostic accuracy of 80-kV(peak) cerebral CTA with 30 mL of contrast agent for detecting intracranial aneurysms.

MATERIALS AND METHODS

Two hundred four patients were randomly divided into 2 groups. Patients in group A (n = 102) underwent 80-kVp CTA with 30 mL of contrast agent, while patients in group B (n = 102) underwent conventional CTA (120 kVp, 60 mL of contrast agent). All patients underwent DSA. Image quality, diagnostic accuracy, and radiation dose between the 2 groups were compared.

RESULTS

Diagnostic image quality was obtained in 100 and 99 patients in groups A and B, respectively (P = .65). With DSA as reference standard, diagnostic accuracy on a per-aneurysm basis was 89.9% for group A and 93.9% for group B. For evaluating smaller aneurysms (<3 mm), the diagnostic accuracy of groups A and B was 86.3% and 90.8%, respectively. There was no difference in diagnostic accuracy between each CTA group and DSA (all, P > .05) or between the 2 CTA groups (all, P > .05). The effective dose in group A was reduced by 72.7% compared with group B.

CONCLUSIONS

In detecting intracranial aneurysms with substantial radiation dose and contrast agent reduction, 80-kVp/30-mL contrast CTA provides the same diagnostic accuracy as conventional CTA.

Enhanced immunity and antiviral effects of an HBV DNA vaccine delivered by a DC-targeting protein

DNA vaccine targeting delivery to DC represents one effective strategy to improve the immunogenicity of the vaccine. In a previous study, we developed a novel DC-targeting recombinant protein that can deliver plasmid DNA to DCs by an electrostatic coupling effect and can thus improve the uptake efficiency of DCs, improving the expression of plasmid DNA in DCs. In this study, we coupled the protein with the HBV DNA vaccine pSVK-HBVA and investigated whether the immunogenicity and antiviral ability of the vaccine can be improved in HBV transgenic mice. The results show that a stronger specific immune response can be induced in mice after immunization with the coupling vaccine. The HBV DNA copy number and circulating antigen HBsAg in the serum of HBV transgenic mice were significantly decreased. Therefore, this study has demonstrated that the DC-targeting protein has the ability to improve the immunogenicity and the antiviral activity of the HBV DNA vaccine pSVK-HBVA. These findings indicate that this DC-targeting protein can be a potential method for the delivery of DNA vaccines directly to DCs.

Invasive pulmonary fungal infections in patients with connective tissue disease: a retrospective study from northern China

Invasive pulmonary fungal infection (IPFI) is a potentially fatal complication in patients with connective tissue disease (CTD). The current study aimed to uncover the clinical characteristics and risk factors of patients with IPFI-CTD. The files of 2186 CTD patients admitted to a single center in northern China between January 2011 and December 2013 were retrospectively reviewed. A total of 47 CTD patients with IPFI were enrolled into this study and assigned to the CTD-IPFI group, while 47 uninfected CTD patients were assigned to the control group. Clinical manifestations were recorded, and risk factors of IPFI were calculated by stepwise logistical regression analysis. Forty-seven (2.15%) CTD patients developed IPFI. Systemic lupus erythematosus patients were responsible for the highest proportion (36.17%) of cases with IPFI. Candida albicans (72.3%) accounted for the most common fungal species. CTD-IPFI patients had significantly elevated white blood cell count, erythrocyte sedimentation rate, C-reactive protein and fasting glucose values compared to controls (P<0.05). Cough, sputum and blood in phlegm were the most common symptoms. Risk factors of IPFI in CTD included maximum prednisone dose ≥30 mg/day within 3 months prior to infection, anti-microbial drug therapy, and interstitial pneumonia. CTD patients who have underlying interstitial pneumonia, prior prednisone or multiple antibiotics, were more likely to develop IPFI.

Abstract 3903: Optimizing the antitumor efficacy of AuNR-assisted plasmonic photothermal therapy and its molecular impact

Plasmonic gold nanorods (AuNRs) are very promising for biomedical applications because of their strongly enhanced radiation (e.g. absorption and scattering) and non-radioactive photothermal properties due to surface plasmon resonance. In plasmonic photothermal therapy (PPTT), AuNRs absorb near infrared (NIR) laser and induce localized heat (i.e., hyperthermia) which can promote tumor tissue ablation. However, the lack of comprehensive studies to improve the efficiency of AuNRs has hindered their application. The objectives of this study were to perform a systematic analysis to optimize AuNR-PPTT based on different sizes, formulation and concentration along with various laser powers for cancer therapy in vitro and in vivo. We used AuNRs of sizes 26×6 nm and 72×19 nm with concentrations of 2.5, 5 and 10 nM, followed by 2 min of 0.5, 1, 1.78 W/cm2 NIR 808 nm diode laser exposure both in vitro and in vivo. For in vitro studies, we studied several head and neck squamous cell carcinoma (HNSCC) cell lines. We conducted an in vivo antitumor efficacy study in nude mice bearing human HNSCC Tu686 xenograft tumors with three formulations of AuNRs (72×19 nm and 26×6 nm with or without rifampicin (Rf) conjugation).Single dose intratumoral injection of 5 nM and 10 nM AuNRs (26×6 nm), followed by 2 min of 1.78 W/cm2 NIR laser exposure inhibited tumor growth and the 2.5 nM dose led to moderate antitumor efficacy. However, we observed severe skin burning at higher concentrations. In contrast, AuNRs (72×19nm) had no remarkable antitumor efficacy at high laser power. Impressively, small AuNR-conjugated Rf (AuNR-Rf) accumulated AuNRs inside the cell and had very significant antitumor efficacy (p&lt;0.05) without any skin burning at 2.5 nM concentration. We confirmed our observations by immunohistochemistry staining of proliferation marker Ki67 in tumor tissues. To understand the molecular impact, we applied the optimized treatment in vitro. AuNR-Rf was able to induce apoptosis in 24 hours of treatment and decreased cell viability, as supported by immunoblotting of PARP and caspase 3 cleavage. In addition, we found that mutant p53 was completely abolished in AuNR-PPTT treatment. Overall, we have demonstrated that 2.5 nM AuNR with 1.78 W/cm2 NIR laser has no remarkable toxicities and optimal antitumor efficacy was observed by conjugation with Rf. In future studies, we will explore potential novel biomarkers by next generation sequencing (NGS) in mouse tumor tissues to determine the response to AuNR-PPTT. (This study supported by U01CA151802).

[M.A.R. and M.R.K.A. contributed equally to this work.]

Citation Format: Mohammad Aminur Rahman, Moustafa R. K. Ali, Zhixiang Zhao, Georgia Z. Chen, Mostafa A. El-Sayed, Dong M. Shin. Optimizing the antitumor efficacy of AuNR-assisted plasmonic photothermal therapy and its molecular impact. [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 3903.

HPV16 E6 and E7 proteins induce a chronic oxidative stress response via NOX2 that causes genomic instability and increased susceptibility to DNA damage in head and neck cancer cells

Human papillomavirus (HPV) is the causative agent of a subgroup of head and neck cancer characterized by an intrinsic radiosensitivity. HPV initiates cellular transformation through the activity of E6 and E7 proteins. E6 and E7 expression is necessary but not sufficient to transform the host cell, as genomic instability is required to acquire the malignant phenotype in HPV-initiated cells. This study reveals a key role played by oxidative stress in promoting genomic instability and radiosensitivity in HPV-positive head and neck cancer. By employing an isogenic human cell model, we observed that expression of E6 and E7 is sufficient to induce reactive oxygen species (ROS) generation in head and neck cancer cells. E6/E7-induced oxidative stress is mediated by nicotinamide adenine dinucleotide phosphate oxidases (NOXs) and causes DNA damage and chromosomal aberrations. This mechanism for genomic instability distinguishes HPV-positive from HPV-negative tumors, as we observed NOX-induced oxidative stress in HPV-positive but not HPV-negative head and neck cancer cells. We identified NOX2 as the source of HPV-induced oxidative stress as NOX2 silencing significantly reduced ROS generation, DNA damage and chromosomal aberrations in HPV-positive cells. Due to their state of chronic oxidative stress, HPV-positive cells are more susceptible to DNA damage induced by ROS and ionizing radiation (IR). Furthermore, exposure to IR results in the formation of complex lesions in HPV-positive cells as indicated by the higher amount of chromosomal breakage observed in this group of cells. These results reveal a novel mechanism for sustaining genomic instability in HPV-positive head and neck tumors and elucidate its contribution to their intrinsic radiosensitivity.

Incidence of acute mountain sickness in young adults at 3200 meters: comparison of the Lake Louise Scoring and Chinese Scoring Systems

The purpose of this study was to compare two scoring systems used for the diagnosis of acute mountain sickness (AMS): the Lake Louise Scoring (AMS-LLS) and the Chinese Scoring Systems (AMS-CSS). In total, 339 healthy young adult volunteers residing at sea level ascended to 3200 m by train and bus over a total journey time of 48 h. All subjects ascended in the same manner and were divided into three groups that were assessed after one (N = 88), two (N = 91), and three (N = 160) nights, respectively, at altitude. The overall incidence of AMS was 17.11% (N = 58) and 29.79% (N = 101) according to the AMS-LLS and AMS-CSS, respectively. Two participants (0.59%) experienced high-altitude pulmonary edema. Both scoring systems showed the highest incidence of AMS after the second night at high altitude. The AMS-CSS and AMS-LLS scores were significantly correlated (Pearson's r = 0.820, P < 0.001). The AMS-CSS identified all AMS subjects diagnosed by the AMS-LLS, and an additional 43 subjects. The dominant symptoms were reduced exercise tolerance (61.7%), fatigue (49.0%), dizziness (28.9%), chest distress (28.3%), and headache (27.4%). Compared with the AMS-LLS, the sensitivity, specificity, and positive and negative predictive values of the AMS-CSS were 100, 84.7, 57.43, and 100%, respectively. There was no relationship between oxygen saturation levels and AMS scores at 3200 m. In summary, the AMS-CSS was similar to AMS-LLS, except that it resulted in more positive diagnoses, and headache did not play a large diagnostic role.

Abstract 1784: NOX-mediated chronic oxidative stress is inherent in human papillomavirus positive head and neck cancer cells and is implicated in radiosensitivity

An increasing subgroup of oropharyngeal carcinomas is caused by infection with high risk types of human papillomavirus (HPV). Recent clinical data suggest that HPV status is an important prognostic factor associated with a favorable outcome in head and neck cancer patients treated with radiation therapy alone or in combination with chemotherapy. Although such data suggest an intrinsic sensitivity of HPV-positive tumors to radio/chemotherapy, no specific mechanism(s) has been shown to explain this feature. As DNA damage repair and/or tolerance capacity is one of the major determinants of sensitivity to DNA damaging agents, we interrogated a panel of five HPV positive (HPV+) and five HPV negative (HPV-) head and neck cancer cell lines for endogenous levels of DNA damage. HPV+ cells display an approximately 100% increase in the level of DNA damage compared to HPV- cells, as revealed by alkaline comet assays. As reactive oxygen species (ROS) represent the major endogenous source of DNA damage, we investigated whether HPV+ cells harbor high levels of ROS. We observed that HPV+ cells have approximately 100% higher levels of ROS compared to HPV- cells, measured by flow cytometry analysis. Treatment with the antioxidant N-acetyl-cysteine resulted in a concomitant reduction of ROS levels (∼35%) and endogenous DNA damage (∼41%) in HPV+ cells, indicating that chronic oxidative stress may contribute to genomic instability in HPV+ head and neck cancer cells. In addition, we found that treatment with the NOX inhibitor diphenylen iodonium reduces the levels of ROS in HPV+ cells (∼50%), indicating that NADPH oxidases are the source of the higher levels of ROS in these cells. Consistent with this mechanism, we observed that NOX-2, an inducible member of the NOXs family, is expressed only in HPV+ cells, suggesting that HPV infection may induce the transcription/translation of NOX-2 in head and neck cells. Collectively these data suggest that HPV infection may induce a state of chronic oxidative stress in head and neck cancer cells that may render HPV+ cells more susceptible to certain types of DNA damage. To test this hypothesis we evaluated the amount of DNA damage induced by exposure to a dose range of H2O2 or ionizing radiation (IR) in HPV+ and HPV- head and neck cancer cells. We found that each dose of H2O2 and IR induced a significantly greater amount of DNA damage in HPV+ cells compared to HPV- cells, indicating that HPV+ head and neck cells may be more prone to ROS-mediated DNA damage. This study provides new insights into HPV+ head and neck cancer cell biology and its sensitivity to IR.

Pilot funding for this project was provided by a grant from the V Foundation.

Citation Format: Rossella Marullo, Hongzheng Zhang, Georgia Z. Chen, William D. Hunt, Dong M. Shin, Paul, W. Doetsch. NOX-mediated chronic oxidative stress is inherent in human papillomavirus positive head and neck cancer cells and is implicated in radiosensitivity. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1784. doi:10.1158/1538-7445.AM2013-1784

Abstract LB-79: Combined treatment with HER3 antibody MM-121/SAR 256212 and EGFR antibody cetuximab in pre-clinical models of head and neck cancer

Background: The EGFR monoclonal antibody cetuximab is approved for treating head and neck squamous cell cancer (SCCHN) in combination with radiation therapy for locally advanced disease and chemotherapy for recurrent and metastatic disease. Intrinsic or compensatory HER3 signaling and sustained PI3K/Akt activation may play a role in resistance to EGFR-targeted therapy. However, the role of HER3 in resistance to EGFR-targeted therapy in SCCHN has not been elucidated. Therefore, we first tested whether the combination of MM-121/SAR 256212 (M), a HER3 antibody being co-developed by Merrimack Pharmaceuticals and Sanofi, with cetuximab (C) may be more effective than M or C alone in treatment of SCCHN. Methods: We screened for the expression of EGFR, HER3 and their activated forms in 12 SCCHN cell lines. We then evaluated the activity of C, M, and their combination (CM) both in vitro by colony formation assay and in vivo by using SCCHN xenograft models (Tu212 and SCC47). In the in vivo experiment, mice were treated by intraperitoneal injection (i.p.) of C, M or CM twice per week for 4 weeks. The experimental groups include a PBS control, C (6.25ug/dose), M at low dose (300ug/dose, LD), M at high dose (600ug/dose, HD), the combination with LD (CMLD), and the combination with HD (CMHD). In addition, we examined the effect of M and C on HER3 and its downstream pathways in SCCHN cell lines by western blot assay. Results: pHER3 was detected in 9/12 while pEGFR, EGFR and HER3 were expressed in all of 12 SCCHN cell lines. The colony formation assay showed that Tu212 cells were significantly inhibited by CM compared to the control (p &lt;0.001), M (p&lt;0.001) and C (p=0.009) alone. Similar results were also observed using the SCC47 cell line. Western blot analysis confirmed the down-regulation of activated HER3 and its downstream phospho-Akt and phospho-S6 ribosomal protein by CM. Our in vivo study showed significant tumor growth inhibition in both MM-121 LD (p&lt;0.001) and MM-121HD (p&lt;0.001) compared to the control. Moreover, the treatment with both CMLD and CMHD significantly suppressed Tu212 xenograft tumor growth compared to the PBS control (both p&lt;0.0001), C alone (both p&lt;0.0001), and MLD (p=0.0046 and 0.0008, respectively), but only CMHD showed significant inhibition compared to MHD (p = 0.02). There was no significant difference between CMLD and CMHD (p=0.5994). Studies using another SCCHN xenograft model (SCC47) showed a similar inhibitory effect from the treatments by C, M and CM. Conclusion: This study shows that the combination of cetuximab and MM-121 is significantly more active than MM-121 or cetuximab alone in models of head and neck cancer in which both EGFR and HER3 are activated. Further studies will be expanded to understand the underlying mechanisms of this combination. (This study was supported by Merrimack Pharmaceuticals Inc.)

Citation Format: Ning Jiang, Dongsheng Wang, Zhongliang Hu, Aminur M. Rahman, Hongzheng Zhang, Ruhul A. Amin, Xiaojing Wang, Zhengjia Chen, Shin M. Dong, Gabriela Garcia, Gavin MacBeath, Jun Ma, Fadlo R. Khuri, Nabil F. Saba, Georgia Z. Chen. Combined treatment with HER3 antibody MM-121/SAR 256212 and EGFR antibody cetuximab in pre-clinical models of head and neck cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr LB-79. doi:10.1158/1538-7445.AM2013-LB-79

Abstract 1298: The role of nuclear factor kappa B in survival of human papillomavirus-positive head and neck cancer cell lines

Nuclear factor kappa B (NFκB) has been implicated in the development of head and neck squamous cell carcinoma (HNSCC) from premalignant changes to tumor progression, and in treatment resistance and recurrence. However, the roles of NFκB in the sensitivity to chemoradiation of human papillomavirus (HPV)-associated HNSCC have not been well defined. Previously we reported that high expression of NFκB detected by immunohistochemistry in pretreated HPV+ oropharyngeal cancer patients was significantly associated with poor progression free survival (AACR 2012 Abstract #4489). Therefore, we hypothesized that NFκB could play a role in pro-survival in HPV+ head and neck cancer cells. We first examined the sensitivity of five HPV+ head and neck cancer cell lines (HPV16: UDSCC2, 93-VU-147T, UM-SCC47, UPCI:SCC90, HPV18: SCC1483) to radiation and cisplatin, Consistent with current models, when we knocked down expression of the HPV16E6 oncogene, SCC47 and SCC1483 cells with restored expression of p53 displayed a significant reduction in S phase entry as revealed by cell cycle analysis (SCC47: scrambled control 14.08% ± 0.55% versus siRNA-E6 6.39% ± 2.40, p=0.004; SCC1483: scrambled control 13.39% ± 1.28% versus 7.49% ± 0.83, p=0.002). In addition, all five cell lines displayed reduced sensitivity to cisplatin compared with cells treated with scrambled control siRNA. The basal level of activated NFκB in HPV+ cell lines was correlated with the sensitivity to radiation and cisplatin as assessed by colony formation and cell growth assays. Suppression of NFκBp65 by siRNA resulted in marked increases in apoptosis associated with reduction of Bcl-2 in both SCC47 and SCC1483 cells. This pattern was more pronounced with increasing doses of the proteasome inhibitor bortezomib (32.5 to 130 nM for 48 to 72 hr). Furthermore, SCC47 and SCC1483 cells treated with siRNA NFκBp65 displayed a significantly greater level of apoptosis induced by radiation or cisplatin compared to cells treated with non-targeted control siRNA, indicating a pro-survival effect for NFκB. Further studies are warranted to delineate the effects of HPV oncogene interactions with NFκB signaling pathways on chemoradiation sensitivity. (This study was supported by the V Foundation).

Citation Format: Hongzheng Zhang, Zhongliang Hu, Ning Jiang, Rossella Marullo, Paul W. Doetsch, William D. Hunt, Georgia Z. Chen, Dong M. Shin. The role of nuclear factor kappa B in survival of human papillomavirus-positive head and neck cancer cell lines. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1298. doi:10.1158/1538-7445.AM2013-1298

Phosphoglycerate mutase 1 coordinates glycolysis and biosynthesis to promote tumor growth

It is unclear how cancer cells coordinate glycolysis and biosynthesis to support rapidly growing tumors. We found that the glycolytic enzyme phosphoglycerate mutase 1 (PGAM1), commonly upregulated in human cancers due to loss of TP53, contributes to biosynthesis regulation in part by controlling intracellular levels of its substrate, 3-phosphoglycerate (3-PG), and product, 2-phosphoglycerate (2-PG). 3-PG binds to and inhibits 6-phosphogluconate dehydrogenase in the oxidative pentose phosphate pathway (PPP), while 2-PG activates 3-phosphoglycerate dehydrogenase to provide feedback control of 3-PG levels. Inhibition of PGAM1 by shRNA or a small molecule inhibitor PGMI-004A results in increased 3-PG and decreased 2-PG levels in cancer cells, leading to significantly decreased glycolysis, PPP flux and biosynthesis, as well as attenuated cell proliferation and tumor growth.

The effects of media properties on the horseradish peroxidase-catalyzed fluorogenic reaction

The effects of media properties including buffers, acidity, solvents and surfactant on horseradish peroxidase-catalyzed fluorogenic reaction were investigated. The results showed that the so-called non-fluorescent hydrogen donors were in fact fluorescent. There existed an acid-base equilibrium in the fluorescent dimer product. For p -hydroxyphenylpropionic acid, a pK(a) value of 8.0 for the product was obtained from its titration curve. The product fluorescence increased with higher pH, however, a longer time was needed to reach the reaction equilibrium due to the pH mismatch problem. Cationic micelles cetyltrimethylammonium bromide and cetyltrimethylammonium chloride could reduce the pH mismatch and offered a way to further increase the determination sensitivity. Finally, a micelle-enhanced flow-injection analysis of horseradish peroxidase is suggested.

Hyperspectral imaging and quantitative analysis for prostate cancer detection

Hyperspectral imaging (HSI) is an emerging modality for various medical applications. Its spectroscopic data might be able to be used to noninvasively detect cancer. Quantitative analysis is often necessary in order to differentiate healthy from diseased tissue. We propose the use of an advanced image processing and classification method in order to analyze hyperspectral image data for prostate cancer detection. The spectral signatures were extracted and evaluated in both cancerous and normal tissue. Least squares support vector machines were developed and evaluated for classifying hyperspectral data in order to enhance the detection of cancer tissue. This method was used to detect prostate cancer in tumor-bearing mice and on pathology slides. Spatially resolved images were created to highlight the differences of the reflectance properties of cancer versus those of normal tissue. Preliminary results with 11 mice showed that the sensitivity and specificity of the hyperspectral image classification method are 92.8% to 2.0% and 96.9% to 1.3%, respectively. Therefore, this imaging method may be able to help physicians to dissect malignant regions with a safe margin and to evaluate the tumor bed after resection. This pilot study may lead to advances in the optical diagnosis of prostate cancer using HSI technology.

Abstract 4498: Prognostic significance of nuclear factor kappa B expression in human papillomavirus-associated oropharyngeal cancer

Nuclear factor kappa B (NFκB) has been implicated in the development of head and neck squamous cell carcinoma (HNSCC) from premalignant changes to tumor progression and recurrence. However, the prognostic significance of cytoplasmic or nuclear localization of NFκB expression in human papillomavirus (HPV)-associated HNSCC has not been investigated largely due to limited patient samples. We hypothesized that cytoplasmic and/or nuclear expression of NFκB may be a poor prognostic factor for tumor recurrence and overall survival (OS) regardless of p16 status. We conducted a retrospective study with archival formalin-fixed paraffin-embedded tumor biopsies collected from 188 patients with oropharyngeal SCC between October 1994 and February 2008 from Emory University Department of Pathology. Median follow-up was 21.7 and 58.0 months for p16- and p16+ patients, correspondingly. Tumors were evaluated for p16 expression (a surrogate marker for HPV) by immunohistochemistry (IHC). Cytoplasmic expression of NFκBp65 by IHC or total expression combining cytoplasmic and nuclear localization were significantly greater in p16- patients (N=58) than p16+ patients (N=130), p&lt;0.05. High cytoplasmic expression of NFκBp65 was significantly associated with poor OS (p=0.0276) and the total expression was associated with recurrence (p=0.0081) by log rank test, whereas nuclear NFκBp65 displayed weak association. Positive nuclear expression significantly correlated with smoking history (p=0.025). In conclusion, p16+ and low total NFκBp65 expression is associated with the best while p16- and high total NFκBp65 is associated with the worst OS in this patient cohort (Table I). (The study was supported by Head and Neck SPORE Grant P50CA128613).

Increased expression of Rab coupling protein in squamous cell carcinoma of the head and neck and its clinical significance

The role of Rab coupling protein (RCP) has not been previously investigated in squamous cell carcinoma of the head and neck (SCCHN). The aim of this study was to explore RCP protein expression and its clinicopathological significance in SCCHN. RCP protein expression in 95 SCCHN samples, 18 vocal nodule epithelia and 16 leukoplakia epithelia samples was analyzed by immunohistochemistry and correlated with clinicopathological parameters and patient outcome. Our data indicated that vocal nodule epithelia, leukoplakia epithelia and SCCHN showed a gradual increase in the expression of RCP protein. RCP overexpression was significantly associated with T classification, clinical staging, lymph node metastasis and recurrence. Survival analysis revealed that a high RCP expression was significantly correlated with shorter overall survival and disease-free survival. In conclusion, RCP protein may contribute to the malignant progression of SCCHN, and serves as a novel prognostic marker in patients with SCCHN.

Tyrosine phosphorylation of mitochondrial pyruvate dehydrogenase kinase 1 is important for cancer metabolism

Many tumor cells rely on aerobic glycolysis instead of oxidative phosphorylation for their continued proliferation and survival. Myc and HIF-1 are believed to promote such a metabolic switch by, in part, upregulating gene expression of pyruvate dehydrogenase (PDH) kinase 1 (PDHK1), which phosphorylates and inactivates mitochondrial PDH and consequently pyruvate dehydrogenase complex (PDC). Here we report that tyrosine phosphorylation enhances PDHK1 kinase activity by promoting ATP and PDC binding. Functional PDC can form in mitochondria outside of the matrix in some cancer cells and PDHK1 is commonly tyrosine phosphorylated in human cancers by diverse oncogenic tyrosine kinases localized to different mitochondrial compartments. Expression of phosphorylation-deficient, catalytic hypomorph PDHK1 mutants in cancer cells leads to decreased cell proliferation under hypoxia and increased oxidative phosphorylation with enhanced mitochondrial utilization of pyruvate and reduced tumor growth in xenograft nude mice. Together, tyrosine phosphorylation activates PDHK1 to promote the Warburg effect and tumor growth.

Analysis of transcriptional factors and regulation networks in laryngeal squamous cell carcinoma patients with lymph node metastasis

The present study was to identify and quantitate differentially expressed proteins in laryngeal squamous cell carcinoma (LSCC) tissues with or without lymph node metastasis and to explore transcriptional factors and regulation networks associated with the process. Tissue specimens were taken from 20 patients with LSCC, including 10 cases of LSCC without metastasis LSCC (N0) and 10 cases of LSCC with metastasis LSCC (Nx). Among the 643 unique proteins identified by using iTRAQ labeling and quantitative proteomic technology, 389 proteins showed an abundance change in LSCC (Nx) as compared to LSCC (N0). Cytoskeleton remodeling, cell adhesion, and immune response activation were found to be the main processes in LSCC metastasis. The construction of transcription regulation networks identified key transcription regulators for lymph node metastasis of LSCC, including Sp1, c-myc, and p53, which may affect LSCC metastasis through the epithelial-mesenchymal transition. Furthermore, our results suggest that ubiquitination may be a critical factor in the networks. The present study provides insights into transcriptional factors and regulation networks involved in LSCC metastasis, which may lead to new strategies for treatment of LSCC metastasis.

Abstract 2342: RSK2 phosphorylates and activates CREB to promote HNSCC cell invasion through upregulation of pro-metastatic MCAM and Fascin-1

Head and neck squamous cell carcinoma (HNSCC) is one of the most common types of human cancer and clinically effective treatment of HNSCC remains difficult due to metastasis. Therefore, it is of immerse clinical interest to identify metastasis-promoting genes in HNSCC tumors to improve prognosis and define targets for therapy. We recently reported that continued expression of p90 Ribosomal S6 kinase 2 (RSK2) contributes to the maintenance of the invasive and metastatic potential of HNSCC cells in vitro and in vivo, respectively. By a phospho-proteomics based study using a phospho-antibody microarray, we identified a spectrum of pro-metastatic proteins whose phosphorylation levels are regulated by RSK2 in HNSCC cells, including CREB, Hsp27, c-Jun, Elk-1, FAK, IRS-1, Jun-B, c-MET, and Stathmin.

CREB is a transcription factor and RSK2 activates CREB by phosphorylating CREB Ser133. To explore the molecular mechanism underlying the RSK2→CREB pathway-mediated pro-invasive signals, we surveyed potential links between RSK2 and known CREB transcription targets that are implied in cell invasion and tumor metastasis, including HPSE-1, IRS-2, MMP2, VEGF, CNN/Cyr61, MCAM, and Fascin-1. RT-PCR results showed that stable knockdown of RSK2 in highly invasive HNSCC cells results in decreased mRNA levels of VEGF, MCAM and Fascin-1. MCAM (melanoma cell adhesion molecule) is one of the immunoglobulin superfamily which is known to be involved in focal adhesion assembly and cell migration. Fascin-1 is a critical hallmark of the invasive phenotype in cancer cells which bundles F-actin and contributes to cell migration and invasion. Using real-time RT-PCR, we confirmed that stable knockdown of RSK2 result in significant decrease in mRNA levels of MCAM and Fascin-1 in the RSK2-expressing, highly invasive HNSCC M4e, 212LN and 37B cells. Moreover, targeting MCAM and Fascin-1 by shRNA in 212LN cells led to significantly increased cell sensitivity to detachment-induced anoikis, which correlated with attenuated cell invasive potential of these cells. In addition, overexpression of MCAM and Fascin-1 in 212LN cells with stable knockdown of RSK2 rescued phenotypes due to lack of RSK2, resulting in increased cell invasion and reduced cell sensitivity to anoikis, compared to RSK2 knockdown cells.

These data together suggest a transcription-dependent mechanism in which RSK2 may signal through CREB to provide anti-anoikis signals and promote HNSCC cell invasion, in part by up-regulated pro-metastatic proteins such as MCAM and Fascin-1. Our studies may shed new insights into understanding of molecular mechanisms underlying HNSCC metastasis and development of novel therapeutic strategies to treat metastatic HNSCC.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2342. doi:10.1158/1538-7445.AM2011-2342

c-Jun NH2-terminal kinase-dependent upregulation of DR5 mediates cooperative induction of apoptosis by perifosine and TRAIL

BACKGROUND

Perifosine, an alkylphospholipid tested in phase II clinical trials, modulates the extrinsic apoptotic pathway and cooperates with tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) to augment apoptosis. The current study focuses on revealing the mechanisms by which perifosine enhances TRAIL-induced apoptosis.

RESULTS

The combination of perifosine and TRAIL was more active than each single agent alone in inducing apoptosis of head and neck squamous cell carcinoma cells and inhibiting the growth of xenografts. Interestingly, perifosine primarily increased cell surface levels of DR5 although it elevated the expression of both DR4 and DR5. Blockade of DR5, but not DR4 upregulation, via small interfering RNA (siRNA) inhibited perifosine/TRAIL-induced apoptosis. Perifosine increased phosphorylated c-Jun NH2-terminal kinase (JNK) and c-Jun levels, which were paralleled with DR4 and DR5 induction. However, only DR5 upregulaiton induced by perifosine could be abrogated by both the JNK inhibitor SP600125 and JNK siRNA. The antioxidants, N-acetylcysteine and glutathione, but not vitamin C or tiron, inhibited perifosine-induced elevation of p-c-Jun, DR4 and DR5. Moreover, no increased production of reactive oxygen species was detected in perifosine-treated cells although reduced levels of intracellular GSH were measured.

CONCLUSIONS

DR5 induction plays a critical role in mediating perifosine/TRAIL-induced apoptosis. Perifosine induces DR5 expression through a JNK-dependent mechanism independent of reactive oxygen species.

Therapeutic Nanoparticles as Controlled Anti-Cancer Medications

The development of therapeutic nanoparticles (TNPs) for cancer treatment is one of the fastest growing research areas in oncology. Accumulating evidence has shown many advantages of TNPs over freely delivered chemotherapeutic drugs, such as enhanced water solubility, tumor-specific accumulation, and antitumor efficacy, while at the same time reducing non-specific tumor toxicity. However, the mechanisms behind these observations and outcomes have not been fully elucidated. Major challenges for applying TNPs in the clinic are to understand precisely how chemotherapeutic agents are released from TNPs and delivered to the targeted tumor tissues/cells, and how the TNPs' biodistribution affects toxicity in major organs. This review focuses on recent exploration of these unresolved issues with comparisons between free drugs and TNPs and between targeted and non-targeted TNPs. Several well-developed TNPs with unique characteristics will be discussed. Their specific applications for the treatment of certain cancer types have shed light on the clinical use of TNPs in cancer therapy.

The role of radial oxygen loss and root anatomy on zinc uptake and tolerance in mangrove seedlings

Root anatomy, radial oxygen loss (ROL) and zinc (Zn) uptake and tolerance in mangrove plants were investigated using seedlings of Aegiceras corniculatum, Bruguiera gymnorrhiza and Rhizophora stylosa. The results revealed that B. gymnorrhiza, which possessed the 'tightest barrier' in ROL spatial patterns among the three species studied, took up the least Zn and showed the highest Zn tolerance. Furthermore, zinc significantly decreased the ROL of all three plants by inhibition of root permeability, which included an obvious thickening of outer cortex and significant increases of lignification in cell walls. The results of SEM X-ray microanalysis further confirmed that such an inducible, low permeability of roots was likely an adaptive strategy to metal stress by direct prevention of excessive Zn entering into the root. The present study proposes new evidence of structural adaptive strategy on metal tolerance by mangrove seedlings.

Abstract 34: Oncogenic tyrosine kinases phosphorylate and inhibit PKM2 to provide a metabolic advantage to tumor growth

Cancer cells show increased aerobic glycolysis and enhanced lactate production compared to healthy cells, a phenomenon known as the Warburg effect. Cell surface growth factor receptors, which often carry tyrosine kinase activities in their cytoplasmic domains, are overexpressed in many human cancers and are believed to play a key role in determining cell metabolism. Thus, we explored the hypothesis that tyrosine kinase signaling, which is commonly increased in tumors, regulates the Warburg effect and contributes to tumorigenesis and maintenance of the tumor.

We performed phospho-proteomics studies and found that oncogenic forms of fibroblast growth factor (FGF) receptor type 1 (FGFR1) inhibit the pyruvate kinase M2 isoform (PKM2) in cancer cells. Pyruvate kinase is a rate-limiting enzyme during glycolysis and catalyzes the production of pyruvate and ATP from phosphoenolpyruvate (PEP) and ADP. Recent studies demonstrated that the enzymatic activity of the pyruvate kinase M2 isoform (PKM2) is inhibited by phosphotyrosine binding; moreover, these researchers found that PKM2 is crucial for aerobic glycolysis and provides a growth advantage to tumors. However, it remains unclear which tyrosine kinase pathways are physiologically responsible for this inhibition of PKM2 activity and which protein factors undergo tyrosine phosphorylation, allowing them to bind to and thereby inhibit PKM2. We found that PKM2 is itself tyrosine phosphorylated in cancer cells and such a physiological modification of PKM2 promotes the switch to aerobic glycolysis from oxidative phosphorylation. FGFR1 directly phosphorylates PKM2 at tyrosine residue 105 (Y105). This inhibits the formation of active, tetrameric PKM2 by disrupting binding of the PKM2 cofactor fructose-1,6-bisphosphate (FBP). Moreover, we found that phosphorylation of PKM2 Y105 is common in human cancers. Immunoblotting revealed that PKM2 is phosphorylated at Y105 in diverse human breast cancer, lung cancer, prostate cancer and leukemia cell lines. Oncogenic tyrosien kianses including BCR-ABL, FLT3-ITD and JAK2 also directly phosphorylate PKM2 Y105 in in vitro kinase assays using purified proteins. Furthermore, the presence of a PKM2 mutant in which phenylalanine is substituted for Y105 (Y105F) in cancer cells leads to decreased cell proliferation under hypoxic conditions, increased oxidative phosphorylation with reduced lactate production, and reduced tumor growth in xenografts in nude mice.

Our findings suggest that tyrosine phosphorylation regulates PKM2 to provide a metabolic advantage to tumor cells, thereby promoting tumor growth. This may represent a common, short-term molecular mechanism underlying the Warburg effect in both leukemias and solid tumors, in addition to the chronic changes believed to be regulated by transcription factors, including hypoxia inducible factor 1 and Myc.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 34.

Abstract 2257: Optical imaging guidance of tumor resection margin for head and neck cancer

Traditional methods for assessing adequacy of head and neck tumor resection rely upon intraoperative palpation or visualization. Positive margins are strongly associated with recurrence and poor patient survival. To ensure the complete tumor removal, surgeons may resect additional peritumoral tissues. During the past decade, intraoperative pathologic consultation by frozen section has become standard. Each round of consultation takes 20 minutes and the average number of such consultation is 3 − 4 per operation, which prolongs the procedure. Two additional potential problems are: (1) it is impossible to locate all cohorts of infiltrating tumor cells; (2) the final pathology may reveal a positive margin when the frozen section was negative. Currently 20 − 30% of head and neck patients that undergo surgery still leave the operating room with an incomplete resection. Thus, major opportunities exist to develop a deep tissue imaging near infrared (NIR) agent and an intraoperative instrumentation that would allow surgeons to visualize microscopic tumors during surgery. The advantage of using optical imaging over radioisotopes is that it avoids continuous exposure of operating room personnel to radioactivity. The cell adhesion molecule integrin αvβ3 is specifically expressed by tumor neovasculature and invading tumor cells, but not by quiescent vessels or normal cells. We exploited integrin overexpression on infiltrating cancer cells for intraoperative detection of tumor margins. We tested a new optical instrumentation in conjunction with the integrin-targeted NIR dye, RGD-IRDye800CW, for assessing malignant tumor margins in an orthotopic head and neck cancer animal model. RGD peptides have high binding specificity to integrin αvβ3. For intraoperative tumor margin detection, we developed an intraoperative wavelength-resolved NIR imaging system. This device offers real-time, portable detection of tumor margins with high stability, faster throughput, and better co-registration than other imaging methods. In our animal model, the tumors infiltrated to the mylohoid neck muscle beyond tumor boundaries and the primary tumor resection left residual infiltrating tumors and metastatic lymph nodes behind, which were easily detected by our technology. We also found NIR signal in several spots of the lungs from the same mice. Histological analysis in correlation to imaging results support that we can detect extremely small cohorts of 20 − 50 tumor cells in intraoperative settings with high specificity. Thus our technology will be ideal in detecting tumor margins intraoperatively because the average number of tumor cells in invading cohorts is 50 − 100 and NIR penetration depth is about 3 − 5 cm. Of note, we found that NIR signals from the RGD peptides were stronger at the edge (rim) of tumors than the center; therefore, the integrin-targeted imaging probe will allow us to detect the tumor margins as well as infiltrating cohorts of tumor cells.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2257.

Abstract 1260: Analysis of death receptor 5 and caspase-8 expression in primary and metastatic head and neck squamous cell carcinoma and their prognostic impact

Death receptor 5 (DR5) and caspase-8 are major components in the extrinsic apoptotic pathway. The alterations of the expression of these proteins during the metastasis of head and neck squamous cell carcinoma (HNSCC) and their prognostic impact have not been reported. The present study analyzes the expression of DR5 and caspase-8 by immunohistochemistry (IHC) in primary and metastatic HNSCCs and their impact on patient survival. Tumor samples in this study included approximately 90 primary HNSCC with no evidence of metastasis and approximately 90 primary HNSCC and their matching lymph node metastasis. IHC analysis revealed a significant loss or downregulation of DR5 expression in primary tumors with metastasis [weight index (WI) = 221 ± 64.9 (mean ± SD), n = 92] and their matching lymph node metastasis (WI = 224 ± 71.6, n = 85) compared to primary tumors with no evidence of metastasis (WI = 250 ± 43.9, n = 94) (P &lt; 0.01). A similar trend was also observed in caspase-8 expression although it is not statistically significant. Downregulation of caspase-8 and DR5 expression was significantly correlated with poorly differentiated tumors compared to moderately and well differentiated tumors (P &lt; 0.05). Univariate analysis indicates that, in HNSCC with no metastasis, higher expression of caspase-8 significantly correlated with better disease-free survival and overall survival (P &lt; 0.05 or 0.001) if mean value is used as a cutoff. However, in HNSCC with lymph node metastasis, higher caspase-8 expression significantly correlated with poorer disease-free survival and overall survival (&lt; 0.05 or 0.01). Similar results were also generated when we combined both DR5 and caspase-8. Moreover, multivariable analysis indicates that in patients without lymph node metastasis, high caspase-8 is significantly associated with better survival after adjusting age and stage (P &lt; 0.0001). Together, we suggest that both proteins may be involved in regulation of HNSCC metastasis. (G.C., D.M.S., F.R.K. and S-Y.S. are Georgia Cancer Coalition Distinguished Cancer Scholars. This study was supported by funds from the Georgia Cancer Coalition Distinguished Cancer Scholar and NIH Head and Neck SPORE P50 CA128613 awards)

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1260.

Tyrosine phosphorylation inhibits PKM2 to promote the Warburg effect and tumor growth

The Warburg effect describes a pro-oncogenic metabolism switch such that cancer cells take up more glucose than normal tissue and favor incomplete oxidation of glucose even in the presence of oxygen. To better understand how tyrosine kinase signaling, which is commonly increased in tumors, regulates the Warburg effect, we performed phosphoproteomic studies. We found that oncogenic forms of fibroblast growth factor receptor type 1 inhibit the pyruvate kinase M2 (PKM2) isoform by direct phosphorylation of PKM2 tyrosine residue 105 (Y(105)). This inhibits the formation of active, tetrameric PKM2 by disrupting binding of the PKM2 cofactor fructose-1,6-bisphosphate. Furthermore, we found that phosphorylation of PKM2 Y(105) is common in human cancers. The presence of a PKM2 mutant in which phenylalanine is substituted for Y(105) (Y105F) in cancer cells leads to decreased cell proliferation under hypoxic conditions, increased oxidative phosphorylation with reduced lactate production, and reduced tumor growth in xenografts in nude mice. Our findings suggest that tyrosine phosphorylation regulates PKM2 to provide a metabolic advantage to tumor cells, thereby promoting tumor growth.

Uptake and accumulation of arsenic by 11 Pteris taxa from southern China

A field survey was conducted at a deserted arsenic (As) mine in Guangxi Province, China to explore new potential As hyperaccumulators. In addition, young plants of 11 Pteris taxa were grown in glasshouse conditions for 12 weeks on As-amended soils with 0, 50 and 200 mg As kg(-1). Results of the field survey showed that the fern Pteris fauriei accumulated over 1000 mg As kg(-1) in its fronds. Of the 11 Pteris taxa, Pteris aspericaulis, Pteris cretica var. nervosa, P. fauriei, Pteris multifida, P. multifida f. serrulata, and Pteris oshimensis were all found to hyperaccumulate As in addition to P. cretica 'Albo-Lineata' and Pteris vittata (already reported as As hyperaccumulators). However, Pteris ensiformis, Pteris semipinnata and Pteris setuloso-costulata showed no evidence of As hyperaccumulation. Results also revealed a constitutive property of As hyperaccumulation in different populations of P. cretica var. nervosa, P. multifida, P. oshimensis and P. vittata.

Combined neuroform intracranial stent and bioactive matrix detachable coil for embolization of a broad-necked persistent primitive trigeminal artery aneurysm. A case report

SUMMARY

We report a patient with a wide-necked aneurysm arising at the bifurcation of the right internal carotid artery and the persistent primitive trigeminal artery (PPTA) treated successfully by Matrix detachable coil occlusion and assisted by a Neuroform intracranial stent. First, a Neuroform self-expanding intracranial stent was delivered via a 5-F Guider Softtip XP and placed as desired, then the aneurysm dome was embolized with two Matrix detachable coils through the interstices of the stent. The aneurysm was 80% occluded angiographically and the parent artery was patent. DSA imaging six months after the procedure showed the aneurysm to be obliterated at angiography and the neck tissue thickness of the aneurysm to be increased, but the parent artery diameter was not impacted. We describe the case in detail and discuss our preliminary experience of using the Neuroform stent and Matrix detachable coils for the treatment of a PPTA wide-necked aneurysm.

The metalloprotease inhibitor 1,10-phenanthroline affects Schistosoma mansoni motor activity, egg laying and viability

The Zn(2+)-chelating metalloprotease inhibitor 1,10-phenanthroline (phenanthroline, 5-150 microM) elicited dose-dependent contraction of the longitudinal and circular (transverse) musculature of adult male schistosomes. At the same concentrations, phenanthroline did not cause contraction of dispersed individual muscle fibres. The phenanthroline-induced contractions were reduced by the inclusion of 100 or 300 microM Zn2+ in the extracellular medium. Phenanthroline (0.5-150 microM) also inhibited the egg production of adult worm pairs in vitro, with a 98% reduction at 50 microM. When worm pairs were exposed to phenanthroline, the males detached from the dish and released the females, resulting in unpaired worms. At the higher concentrations (50 and 150 microM), the worms were killed in vitro. Worm burdens were reduced by over 50% in infected mice injected with phenanthroline (20 mg/kg/day for 4 days), but twice the dose resulted in only a 25% reduction. Phenanthroline injections also induced an hepatic shift and an unpairing of adult worms in infected mice, and the female worms appeared degenerate and lacked gut pigmentation. Mice fed a diet containing 0.3% phenanthroline received significant protection from infection when challenged with schistosome cercaria, where phenanthroline-fed mice had 94% fewer adult worms than control mice. The broad range of phenanthroline effects on schistosomes suggests broad and important functions for metalloproteases in these worms.

Cholinergic inhibition of muscle fibres isolated from Schistosoma mansoni (Trematoda:Digenea)

Cholinergic compounds inhibit FMRFamide-induced contractions in dispersed muscle fibres isolated from adult Schistosoma mansoni. Acetylcholine (ACh) was the most effective cholinergic agonist tested with an EC50 < 100 nM. Less effective were propionylcholine and arecoline with EC50 < 1 microM and butyrylcholine and carbachol with EC50 < 10 microM. Choline, muscarine, pilocarpine, nicotine, DMPP (1,1-dimethylphenylpiperazine) and levamisole were all ineffective. Amongst tested antagonists, d-tubocurarine (100 microM), mecamylamine (1 mM), scopolamine (1 mM) and quinuclidinyl benzilate (10 microM) were all ineffective. Bicuculline, picrotoxin and strychnine were also ineffective. However alpha-bungarotoxin, at 100 nM, was able to block the inhibitory ACh effect. From these data it appears that the cholinergic receptor on the schistosome muscle fibres may be of the nicotinic type, but that its pharmacology is different from that of nicotinic receptors of vertebrates as well as of nematodes or a variety of other invertebrates.

[Effect of jiawei sijunzi decoction on migrating myoelectric complex in 8 Gy irradiated rats]

The normal intestinal migrating myoelectric complex (MMC) of rats recorded by implanted electrode consists of four phases (phase I, II, III and IV). After 8 Gy of gamma-radiation for 1 hour to 7 days, the MMC cycle in most of the rats were disappeared only phase I or II existed with minute's rhythm. 1 hour or 3 days after radiation, the MMC cycle appeared in a few rats with the phase II shortened significantly (P < 0.05). Results of observation on effect of Jiawei Sijunzi Decoction on MMC after radiation showed the changed phase and cycle of MMC were normalized basically by the medication. These results suggested that the Jiawei Sijunzi decoction could improve the intestinal disturbances caused by radiation, it might be one of the reason of its alleviating effect on the radiation diarrhea.

Immunohistochemical localization of a Shaker-related voltage-gated potassium channel protein in Schistosoma mansoni (Trematoda: Digenea)

We have recently isolated a cDNA (SKv1.1) encoding a Shaker-related K+ channel from the human parasitic trematode Schistosoma mansoni. In order to better understand the functions of SKv1.1 protein, the distribution of SKv1.1 protein in adult S. mansoni was analyzed by immunohistochemistry using a region-specific antibody. SKv1.1 proteins were widely expressed in the nervous and muscular systems. The strongest immunoreactivity (IR) was observed in the nervous system of both male and female. In the nervous system, IR for SKv1.1 proteins was localized in cell bodies and nerve fibers of the anterior ganglia, the central commissure, and the main nerve cords. IR was also observed in the dorsal and the ventral peripheral nerve nets, fine nerve fibers entering into a variety of structures such as the dorsal tubercles, longitudinal and ventral muscle fibers, and oral and ventral suckers. In the muscular system, SKv1.1 proteins were localized to the longitudinal, circular, and ventral muscle fibers of male as well as in isolated muscle fibers where native A-type K+ currents were measured. Moderate IR was also seen in a large number of cell bodies in the parenchyma. These results indicate that SKv1.1 protein may play an important role in the regulation of the excitability of neurons and muscle cells of S. mansoni.

Restriction fragment length polymorphism of the apolipoprotein B gene and response to dietary fat and cholesterol

OBJECTIVE

The relationship between response to dietary fat and cholesterol, and the EcoRI restriction fragment length polymorphism (RFLP) of the apolipoprotein B(apoB) gene was examined.

DESIGN

Forty-nine free-living subjects took part in a prospective double-blind crossover dietary intervention study. The apoB EcoRI cutting site was present in five women and 18 men (E+) and absent in 15 women and 11 men (E-).

INTERVENTION

Subjects consumed a low fat (25% energy), low cholesterol (less than 200 mg/day) diet. After two weeks on this background diet (baseline) subjects were randomly assigned to consume a liquid supplement for three weeks which was either fat and cholesterol free or which contained fat (30 to 36 g) and cholesterol (650 to 780 mg). After the first three-week period subjects switched to the other supplement. Blood samples were collected for plasma lipid analysis after an overnight fast on two consecutive days at the end of baseline and on three consecutive days after each three-week supplement period.

RESULTS

There was no significant difference in response to diet between the RFLP groups. Changes in plasma total, low density lipoprotein (LDL), high density lipoprotein(HDL), HDL2 and HDL3 cholesterol or plasma triglyceride were not different between the two RFLP groups. There was a significant difference between RFLP groups for baseline HDL2-cholesterol (0.31 +/- 0.04 and 0.16 +/- 0.02 mmol/L for E- and E+ subjects, respectively) which was independent of sex and apoE genotype (P = 0.032).

CONCLUSIONS

These results indicate that the EcoRI RFLP of the apoB gene is not associated with response to dietary fat and cholesterol.

Human high molecular weight-melanoma associated antigen mimicry by mouse anti-idiotypic monoclonal antibody MK2-23: modulation of the immunogenicity in patients with malignant melanoma

The mouse anti-idiotypic (anti-id) mAb MK2-23 bears the mirror image of the antigenic determinant defined by antihuman high molecular weight-melanoma associated antigen (HMW-MAA) mAb 763.74. The purpose of this study was to evaluate the effect of conjugation to a carrier and administration with an adjuvant and cyclophosphamide (CTX) on the immunogenicity of anti-id mAb MK2-23 in patients with malignant melanoma and to analyze the relationship between development of humoral immunity and survival time of patients. Fifty-eight patients were sequentially entered into four immunization protocols which included administration of mAb MK2-23, mAb MK2-23 conjugated to keyhole limpet hemocyanin (KLH) and mixed with Bacillus Calmette-Guérin (BCG), mAb MK2-23 and CTX, and mAb MK2-23 conjugated to KLH and mixed with BCG and CTX. Six patients could not be evaluated since they withdrew from the clinical trial after the first immunization. Sera were tested for the development of anti-anti-id antibodies, including those reacting with HMW-MAA. Testing of sera for development of antimouse Ig antibodies was used to monitor the immune competence of patients. Conjugation to KLH and administration with BCG markedly enhanced the ability of mAb MK2-23 to induce anti-anti-id antibodies, including those reacting with HMW-MAA. In contrast, pretreatment with CTX had no detectable effect on the ability of mAb MK2-23 to elicit a humoral anti-anti-id response. Kaplan-Meier survival analysis showed that the performance status of patients, anti-anti-id antibody level, and development of anti-HMW-MAA antibodies had an effect on survival time. This effect was found when the survival time was calculated both from the day of the first immunization and from 4 weeks after the first immunization to the end of the study. A multivariate analysis by Cox regression showed that the development of anti-HMW-MAA antibodies was the most important variable for predicting survival, and that performance status was the only variable that significantly added to the prediction of survival. These data have to be interpreted with caution because of the retrospective nature of the analysis. Nevertheless, the present study suggests that mAb MK2-23 represents a useful immunogen to implement active, specific immunotherapy in patients with malignant melanoma.

Isoprenylation of proteins in the protozoan Giardia lamblia

We report the ability of Giardia lamblia to modify several of its cellular proteins by isoprenylation. Trophozoites cultured in the presence of [3H]mevalonate synthesized radiolabeled proteins of approx. 50 and 21-26 kDa. Chemical analysis indicated that farnesyl and geranylgeranyl isoprenoids comprised the majority of the radiolabel covalently associated with trophozoite proteins. In addition, antibodies to human p21ras immunoprecipitated mevalonate-labelled species of approx. 21 kDa. Inhibitors of several enzymatic steps of the mevalonate pathway dramatically affected Giardia metabolism. Protein isoprenylation and cell growth were blocked by compactin and mevinolin, competitive inhibitors of HMG-CoA reductase, the rate-limiting enzyme in isoprenoid biosynthesis. In the presence of these inhibitors, Giardia growth was restored by the addition of mevalonate to the culture medium. In contrast, cell growth was blocked irreversibly by inhibitors of subsequent steps in the protein isoprenylation pathway. Trophozoite growth inhibition by limonene, perillic acid, perillyl alcohol and N-acetyl-S-farnesyl-L-cysteine was not reversed after the addition of mevalonate, dolichol, ubiquinone or cholesterol to the medium. These observations constitute the first description of protein isoprenylation in any protozoan and indicate that this post-translational modification is an important step in the regulation of the growth of this primitive eukaryote.

Characterization of mevalonate-labeled lipids isolated from parasite proteins in Schistosoma mansoni

Adult paired schistosomes incubated for 3 days in radiolabeled mevalonate can effectively label at least 2 major proteins with apparent sizes of 25 and 43 kDa. The 25-kDa mevalonate-labeled proteins comigrated with proteins that could be labeled with GTP. The lipids attached to these proteins were removed and resolved by HPLC and found to comigrate with known samples of farnesol and geranylgeraniol. Homogenates of the schistosome when incubated with labeled farnesol pyrophosphate effectively labeled a protein(s) with an apparent molecular weight of 43 kDa while homogenates incubated in the presence of labeled geranylgeranyl pyrophosphate-labeled schistosome proteins with an apparent molecular weight of 25 kDa. Our results demonstrate that Schistosoma mansoni has the ability to covalently attach farnesol and geranylgeranyl to low-molecular weight proteins.

Effect of Cordyceps sinensis on erythropoiesis in mouse bone marrow

The effect of Cordyceps sinensis crystal (CS-Cr) on stimulating proliferation of erythroid progenitor cells (CFU-E and BFU-E) in LACA mouse marrow in vivo and in vitro by methyl cellulose gel culture system is reported. The numbers of CFU-E and BFU-E were increased after 5 consecutive daily treatment with 100, 150 and 200 mg/kg of CS-Cr with a peak at 150 mg/kg. Higher doses (> 150 mg/kg) of CS-Cr resulted in a reduction of the peak of CFU-E and BFU-E and then, the numbers returned to the control level with increased doses. The cytosine arabinoside (Ara-C) suicide test showed significant increases in the percentage of CFU-E and BFU-E in S-phase after CS-Cr treatment. Pretreatment of mice with CS-Cr could protect CFU-E and BFU-E against the cytotoxic agent--harringtonine. Addition of CS-Cr to culture system also promoted the generation of CFU-E and BFU-E at concentrations of 150-200 micrograms/ml in vitro. With a liquid culture technique, a stimulatory action of CS-Cr on fibroblast colony-forming units (CFU-F) proliferation was seen in vivo and in vitro.