Platelets in the immune response: Revisiting platelet-activating factor in anaphylaxis.

Anaphylaxis is an acute, severe, life-threatening multisystem allergic reaction resulting from the sudden systemic release of biochemical mediators and chemotactic substances. Release of both preformed granule-associated mediators and newly generated lipid-derived mediators contributes to the amplification and prolongation of anaphylaxis. Platelet-activating factor (PAF) is a potent phospholipid-derived mediator the central role of which has been well established in experimental models of both immune-mediated and non-immune mediated anaphylaxis. It is produced and secreted by several types of cells, including mast cells, monocytes, tissue macrophages, platelets, eosinophils, endothelial cells, and neutrophils. PAF is implicated in platelet aggregation and activation through release of vasoactive amines in the inflammatory response, resulting in increased vascular permeability, circulatory collapse, decreased cardiac output, and various other biological effects. PAF is rapidly hydrolyzed and degraded to an inactive metabolite, lysoPAF, by the enzyme PAF acetylhydrolase, the activity of which has shown to correlate inversely with PAF levels and predispose to severe anaphylaxis. In addition to its role in anaphylaxis, PAF has also been implicated as a mediator in both allergic and nonallergic inflammatory diseases, including allergic rhinitis, sepsis, atherosclerotic disease, and malignancy, in which PAF signaling has an established role. The therapeutic role of PAF antagonism has been investigated for several diseases, with variable results thus far. Further investigation of its role in pathology and therapeutic modulation is highly anticipated because of the pressing need for more selective and targeted therapy for the management of severe anaphylaxis.

Evaluation of E-cadherin, ß-catenin and vimentin protein expression using quantitative immunohistochemistry in nasopharyngeal carcinoma patients.

PURPOSE: Aberrant expression of proteins involved in epithelial-to-mesenchymal transition have been described in various cancers. In this retrospective study, we sought to evaluate E-cadherin, ß-catenin and vimentin protein expression in non-metastatic nasopharyngeal (NPC) patients treated with curative intent, examine their relationship with each other, and with clinical outcome measures. METHODS: Pre-treatment formalin-fixed paraffin-embedded biopsies of 140 patients treated between January 2000 and December 2007 were assembled into a tissue microarray (TMA). Automated quantitative immunohistochemistry (AQUA®) was performed on sequential TMA sections stained with fluorescent-labeled antibodies against E-cadherin, ß-catenin and vimentin. Cox proportional hazards regression was used to estimate the effect of cytoplasmic vimentin, cytoplasmic E-cadherin, ß-catenin nuclear/cytoplasmic ratio expression on overall survival and disease-free survival. RESULTS: The average age of the patients was 51.7 years (SD=12.1; range 18-85), 66% were male, 71% had a KPS ≥ 90% at the start of treatment and 65% had stage III/IV disease. After adjusting for performance status, WHO and stage, high E-cadherin levels over the 75th percentile were found to produce a significantly increased risk for both a worse overall survival (HR = 2.53, 95% CI 1.21, 5.27) and disease free survival (DFS; HR = 2.14, 95%CI 1.28, 3.59). Vimentin levels over the first quartile produced an increased risk for a worse DFS (HR = 2.21, 95% CI 1.11, 4.38). No association was seen between ß-catenin and survival. CONCLUSION: In this cohort of NPC patients, higher levels of E-cadherin and higher levels of vimentin were associated with worse outcomes. Further work is needed to understand the role of these epithelial mesenchymal transition proteins in NPC.

ATM, THMS, and RRM1 protein expression in nasopharyngeal carcinomas treated with curative intent.

BACKGROUND: In advanced nasopharyngeal carcinoma (NPC), biomarkers may help predict survival. METHODS: Tumoral expression of ataxia-telangiectasia mutated (ATM), thymidylate synthetase (THMS), and ribonucleotide reductase subunit M1 (RRM1), was correlated with survival in patients with nonmetastatic NPC using quantitative fluorescence immunohistochemistry with automated quantitative digital image analysis. RESULTS: Of the 146 patients included, 58 patients (40%) received concurrent chemoradiation therapy; the remainder was treated with radiation. Overall survival (OS) at 5 years was 71% (95% confidence interval [CI], 62% to 78%); disease-free survival (DFS) was 48% (95% CI, 39% to 57%). OS worsened for increasing values of ATM (hazard ratio [HR], 2.83; 95% CI, 1.01-7.94; p = .049) for values greater than the 75th percentile compared to less than the 25th percentile, but improved for tumors with higher THMS levels (HR, 0.44; 95% CI, 0.20-0.94; p = .033) for values greater than the 25th percentile compared to less than or equal to the 25th percentile. RRM1 was not associated with OS (p = .748). No biomarkers were associated with DFS. CONCLUSION: In our cohort, relative overexpression of ATM and low THMS levels were associated with worse OS. © 2015 Wiley Periodicals, Inc. Head Neck 38: E384-E391, 2016.

Dose delivery analysis of weekly versus 3-weekly cisplatin concurrent with radiation therapy for locally advanced nasopharyngeal carcinoma (NPC).

OBJECTIVE: The purpose of this study was to analyze the dose delivery and toxicity of weekly cisplatin versus high-dose cisplatin given every 3 weeks in a tertiary oncology clinic. METHODS: From January 2000 to July 2009, patients with biopsy-proven nasopharyngeal carcinoma receiving concurrent cisplatin with curative-intent radiation therapy (RT) were included. Before 2005, most patients received cisplatin (Q3) (100 mg/m intravenously days 1, 22, and 43 of RT) and 3-dimensional conformal RT (66 Gy, 33 fractions). After 2005, most patients received weekly cisplatin (Q1) (40 mg/m intravenously weekly for 7 wk of RT) and intensity-modulated radiotherapy (70 Gy, 35 fractions). RESULTS: Seventy-three patients were analyzed: 45 for Q1 and 28 for Q3. Cumulative doses ≥200 mg/m were achieved in 80% of Q1 and 86% of Q3 patients, respectively. Dose reduction due to toxicity was required in 2/45 (4%) of Q1 patients compared with 11/28 (39%) of Q3 patients (P=0.0003). Toxicities in Q1 and Q3 patients included: hospitalization for acute toxicity in 20% and 35.7%; mean weight loss 10.85% and 8.75%; percutaneous endoscopic gastrostomy tube placement in 25.6% and 29.6%; and grade 3 dehydration in 11.1% and 17.9%, respectively. Median follow-up time was 3 years for Q1 and 6 years for Q3 patients. Median disease-free survival was 46 months for the Q1 group and 53 months for the Q3 group (P=0.667). There was no difference in overall survival between Q1 and Q3. CONCLUSIONS: In this series, weekly 40 mg/m cisplatin and 3-weekly 100 mg/m cisplatin showed similar deliverability, toxicity profiles, and outcomes. At our center, weekly cisplatin is standard of care for patients with locally advanced nasopharyngeal carcinoma undergoing chemoradiotherapy.

Effect of ketotifen premedication on adverse reactions during peanut oral immunotherapy.

BACKGROUND: Oral immunotherapy (OIT) has shown promise in inducing desensitization for food allergy. However, there are safety concerns regarding the frequency and severity of adverse events during food OIT. OBJECTIVE: To evaluate the effect of Ketotifen premedication on adverse reactions during peanut OIT. METHODS: A randomized single blind placebo controlled pilot study was performed. Peanut OIT was performed using a previously published protocol. Ketotifen was up-titrated to 2 mg twice daily over two weeks (week -2 to 0), followed by a peanut OIT initial escalation day (day 1). Ketotifen was administered from week 0-4 of peanut OIT; reactions to peanut OIT doses were recorded by clinic staff and subject diary. RESULTS: Six subjects (median age 10 years, peanut IgE >100kUA/L) were enrolled, 4 randomized to Ketotifen, 2 to placebo. The most common side effect of Ketotifen was fatigue (9% during up-titration). The rate of reaction per peanut OIT dose was lower for subjects on ketotifen (K) compared to placebo (P) during initial escalation on day 1 (K: 22% (8/36) vs. P: 67% (12/18)); week 0-4 build-up doses (K: 75% (3/4) vs. P: 100% (2/2)); and week 0-4 home doses (K: 50% (54/108) vs. P: 82% (27/33)). The rate of gastrointestinal symptoms per peanut OIT dose was also lower for subjects on ketotifen during initial escalation on day 1 (K: 17% (6/36) vs. P: 61% (11/18)); week 0-4 build-up doses (K: 75% (3/4) vs P: 100% (2/2)); and week 0-4 home doses (K: 46% (50/108) vs. P: 82% (27/33)). CONCLUSIONS: Ketotifen premedication is well tolerated and reduces the rate of gastrointestinal symptoms during peanut OIT. These findings require confirmation in a larger study of Ketotifen premedication used throughout peanut OIT. CLINICAL TRIALS NUMBER: NCT0162515.

Assessment of ERCC1 and XPF protein expression using quantitative immunohistochemistry in nasopharyngeal carcinoma patients undergoing curative intent treatment.

PURPOSE: We sought to evaluate the prognostic/predictive value of ERCC1 and XPF in patients with nonmetastatic nasopharyngeal carcinoma (NPC) treated with curative intent. METHODS AND MATERIALS: ERCC1 and XPF protein expression was evaluated by immunofluorescence combined with automated quantitative analysis (AQUA) using the FL297 and 3F2 antibodies, respectively. ERCC1 and XPF protein expression levels were correlated with clinical outcomes. RESULTS: Patient characteristics were as follows: mean age 52 years (range, 18-85 years), 67% male, 72% Karnofsky performance status (KPS) ≥ 90%, World Health Organization (WHO) type 1/2/3 = 12%/28%/60%, stage III/IV 65%. With a median follow-up time of 50 months (range, 2.9 to 120 months), the 5-year overall survival (OS) was 70.8%. Median standardized nuclear AQUA scores were used as cutpoints for ERCC1 (n=138) and XPF (n=130) protein expression. Agreement between dichotomized ERCC1 and XPF scores was high at 79.4% (kappa = 0.587, P<.001). Neither biomarker predicted locoregional recurrence, DFS, or OS after adjustment for age and KPS, irrespective of stratification by stage, WHO type, or treatment. CONCLUSIONS: Neither ERCC1 nor XPF, analyzed by quantitative immunohistochemistry using the FL297 and 3F2 antibodies, was prognostic or predictive in this cohort of NPC patients.

Prospective evaluation of TLE1 as a diagnostic immunohistochemical marker in synovial sarcoma.

Synovial sarcoma is a high-grade soft tissue sarcoma that can be challenging to diagnose on the basis of histology alone. It is defined by a characteristic translocation t(X;18) that produces the fusion oncogene SYT-SSX. The current diagnostic gold standard for synovial sarcoma is the demonstration of the translocation by fluorescence in situ hybridization, reverse transcriptase polymerase chain reaction, or cytogenetics, in an appropriate histologic context. TLE1 encodes a transcriptional corepressor that is overexpressed in synovial sarcomas. Gene and tissue microarray studies have identified TLE1 as an excellent bio-marker for distinguishing the synovial sarcoma from other soft tissue malignancies. We prospectively evaluated incoming soft tissue tumor cases where the histology and clinical setting made synovial sarcoma a real consideration in the differential diagnosis. TLE1, Bcl2, epithelial membrane antigen, and cytokeratin expression were assessed using commercially available antibodies. TLE1 gave intense, diffuse nuclear staining in 35 of 35 molecularly confirmed synovial sarcoma cases, and was rare to absent in the 73 other soft tissue tumors examined (positive staining was found only in 1 of 43 malignant peripheral nerve sheath tumors, the 1 tested fibrosarcoma, and 1 pleomorphic sarcoma). TLE1 was more sensitive and specific for synovial sarcoma than other currently available immunohistochemical markers including Bcl2, epithelial membrane antigen and cytokeratins, and had a positive predictive value of 92% and a negative predictive value of 100% in this clinical setting. Our findings confirm, in a prospective diagnostic context, that TLE1 is more sensitive and specific for synovial sarcoma than any other currently available immunohistochemical stains, and in some cases may preclude the need for molecular testing.