Rapid and sensitive electrochemiluminescence detection of rotavirus by magnetic primer based reverse transcription-polymerase chain reaction

A novel method for detection of rotavirus has been developed by integrating magnetic primer based reverse transcription-polymerase chain reaction (RT-PCR) with electrochemiluminescence (ECL) detection. This is realized by accomplishing RT of rotavirus RNA in traditional way and performing PCR of the resulting cDNA fragment on the surface of magnetic particles (MPs). In order to implement PCR on MPs and achieve rapid ECL detection, forward and reverse primers are bounded to MPs and tris-(2,2'-bipyridyl) ruthenium (TBR), respectively. After RT-PCR amplification, the TBR labels are directly enriched onto the surface of MPs. Then the MPs-TBR complexes can be loaded on the electrode surface and analyzed by magnetic ECL platform without any post-modification or post-incubation process. So some laborious manual operations can be avoided to achieve rapid yet sensitive detection. In this study, rotavirus in fecal specimens was successfully detected within 1.5 h. Experimental results showed that the detection limit of the assay was 0.2 pg μL(-1) of rotavirus. The ECL intensity was linearly with the concentration from 0.2 pg μL(-1) to 400 pg μL(-1). What's more, the specificity of this method was confirmed by detecting other fecal specimens of patients with nonrotavirus-associated gastroenteritis. We anticipate that the proposed magnetic primer based RT-PCR with ECL detection strategy will find numerous applications in food safety field and clinical diagnosis.

P5-18-09: The Incidence of Febrile Neutropenia in the First Course of Adjuvant Chemotherapy with Docetaxel/Cyclophosphamide with or without Pegfilgrastim

Background

In our original doxorubicin-cyclophosphamide/docetaxel-cyclophosphamide (AC/TC) adjuvant study (JCO 27: 1177–1183, 2009), we reported an incidence of febrile neutropenia (FN) of 5% (8% in women ≥65 years) with the TC regimen without prophylactic WBC growth factors but with a recommendation for prophylactic antibiotics. There is a paucity of data on the incidence of FN with the TC regimen aside from this clinical trial. Because we have been conducting a randomized adjuvant study of TC compared to other regimens, we used this opportunity to analyze the incidence of FN during the first course of chemotherapy with TC in the first cohort of randomized patients (US Oncology Network study 06090). The prophylactic use of WBC growth factors was at the investigator's discretion.

Patients and Methods

The study included 1298 patients entered between May 2007 and May 2009. Of these, 649 were included in the TC arm. Median age was 54 years (range 27–71), 75.5% were Caucasian, 561 (86.4%) were in PS 0 at baseline, and about half were node negative. Eight patients did not receive study treatment for various reasons. Among the 641 patients who received TC; 213 (33.3%) received pegfilgrastim, 48 (7.5%) received filgrastim and were not included in this analysis, and 380 (59.2%) patients did not receive either during the first cycle. Thus, this analysis focused on 593 women who did or did not receive prophylactic pegfilgrastim in cycle 1.

Results: All patients with a reported adverse event of FN or with a reported AE of fever with some degree of neutropenia (in order to capture all possible cases of FN) during the first cycle of TC were identified [Table 1]. FN and fever + neutropenia occurred in a total of 6 (2.8%) patients who received pegfilgrastim and 36 (9.5%) patients who did not. A comparison of age, race, performance status and stage of disease between these 2 groups revealed that they were similar. The 213 patients who received pegfilgrastim were slightly older (median 56 years, range 27–71) compared to those who did not (median 53 years, range 30–71).

Three-Year Follow-Up of Survival and Progression in a Phase II Trial of Gemcitabine Plus Carboplatin (Plus Trastuzumab in HER2+ Patients) in Metastatic Breast Cancer Patients

Background: We have previously reported (Loesch, et al. Clin Breast Cancer, 2008) the efficacy and safety of gemcitabine and carboplatin with or without trastuzumab in patients with metastatic breast cancer. We now report time-to-progression (TTP) and overall survival (OS) after up to 3.5 years of extended follow-up.Patients and Methods: Patients were stratified into 3 groups at registration; Group 1: HER2 positive (+) regardless of prior taxane; Group 2: HER2 negative (–) and taxane naïve or remote (no taxanes within the past 2 years); and Group 3: HER2– and taxane pretreated. Women ≥18 years of age, with ECOG performance status 0-2, with RECIST-defined measurable disease, and either HER2– or HER2+ (3+ score) by immunohistochemistry or fluorescence in situ hybridization were enrolled. Treatment: Day 1 gemcitabine 1500 mg/m2 over 30 minutes followed by carboplatin AUC=2.5 repeated every 14 days up to Cycle 9. Group 1 also received trastuzumab 8 mg/kg in Cycle 1 followed by 4 mg/kg in Cycles 2-9, followed thereafter by 6 mg/kg every 21 days until progression or intolerable toxicity.Results: A total of 150 patients were registered (50, 51, and 49 in Groups 1, 2, and 3, respectively). Median follow-up for surviving patients, calculated from registration, was 31.3, 27.1, and 25.4 months, respectively. Median TTP (calculated as progression-free survival), was 7.2, 5.6, and 4.6 months, respectively. Median OS (range) has not been reached for Group 1 (range, 1.2-46.9); for Group 2 was 21.7 months (<1-44.3); and, for Group 3 was 11.9 months (<1-33.6). At 24-months, survival rates were 73.3%, 41.4%, and 20.5%, respectively; at 36-months, survival rates were 60.6%, 25.7%, and ≤8.3%, respectively. For Group 1 only, the remaining 3 responding patients were followed for 3.5 years, at which time they were relapse-free.Conclusions: Gemcitabine plus carboplatin with or without trastuzumab has been shown to be highly active in metastatic breast cancer. HER2+ patients receiving trastuzumab had the highest TTP and survival rates of all treatment groups. As expected, taxane-pretreated patients had shortened TTP and decreased OS rates compared to taxane-naïve patients.Research support was provided, in part, by Lilly USA, LLC; Indianapolis, IN.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 2105.

The multi-institutional myeloma group clinico-genomic risk stratification system: A blinded validation

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Background: Several clinical and molecular prognostic factors (e.g, International Staging System [ISS] stage, plasma cell labeling index, genomic models) exist for multiple myeloma (MM). We hypothesized that exploiting gene signatures representative of oncogenic pathway deregulation (i.e., Ras, Myc, etc.), would improve MM prognostication and also aid with the identification of novel therapeutic targets. Methods: Using a discovery cohort (n=47) of patients with MM and corresponding gene expression data, we built upon current molecular risk-stratification and devised a Bayesian genomic (“metagene”) model for prognosis. We validated that model in an independent patient cohort (n=207). Finally, we incorporated ISS staging and clinical variables to construct a combined Clinico-Genomic Risk Stratification System. We further validated the combined model in a separate cohort (n=72), in a blinded manner. Results: Using gene signatures predictive of oncogenic pathway activation in the discovery cohort, we identified specific patterns (metagenes) of signaling pathway activation with prognostic relevance. In an independent validation cohort, this metagene-based model accurately predicted event free survival (EFS) independently of ISS (multivariate hazard ratio [HR] 3.4 for ISS stage, and 5.4 for the metagene model, p=0.002). Using multivariate risk modeling, we incorporated ISS staging and the metagene model into a Clinico-Genomic System and successfully stratified the validation cohort into three groups (low, intermediate, and high risk) with markedly different EFS (HR 4.2 for intermediate risk and 14.0 for high risk vs. the low risk cohort, p<0.0001). In an additional blinded validation, the Clinico-Genomic System again accurately predicted median overall survival (68.7 [low risk] vs 24.7 [intermediate risk] vs 18.7 months [high risk], p<0.0001); more accurately than either ISS or other reported genomic models. Conclusions: A combined Clinico-Genomic Risk Stratification System, building on patterns of oncogenic pathway activation and ISS staging system, improves upon current prognostic models in MM and identifies novel pathway targets for future therapeutic consideration.

No significant financial relationships to disclose.

Desorption and ripening of low density InAs quantum dots

In this paper, combining low deposition rate with proper growth temperature, we have developed a way to prepare very low-density quantum dots (QDs) suited for the study of single QD properties without resorting to submicron lithography. Experiment results demonstrate that InAs desorption is significant during growing the low density QDs. Ripening of InAs QDs is clearly observed during the post-growth annealing. Photoluminescence spectroscopy reveals that the emission wavelength of low density InAs QDs arrives at 1332.4 nm with a GaAs capping layer.

Phase II trial of docetaxel and oxaliplatin in patients with advanced gastric cancer and/or adenocarcinoma of the gastroesophageal junction

BACKGROUND

Platinum-based chemotherapy is the standard treatment for advanced gastric cancer (GC). This trial explored the efficacy and tolerability of combined docetaxel (Taxotere) + oxaliplatin (DOCOX) in GC patients.

PATIENTS AND METHODS

Patients with untreated stage IV GC or adenocarcinoma of the gastroesophageal junction (AGEJ) received docetaxel 60 mg/m(2) followed by oxaliplatin 130 mg/m(2) on day 1 of each 21-day cycle until progression or unacceptable toxicity. The primary end points were response rate (RR), toxicity, progression-free survival (PFS), and overall survival (OS).

RESULTS

Baseline characteristics (N = 71): median age 59 years, 72% male, 51% esophagogastric junction cancer, and Eastern Cooperative Oncology Group performance status of zero, one, two were 42%, 51%, 7%, respectively. The median number of cycles was 6 (range, 1-19). Grades 3-4 toxic effects: neutropenia (70%); vomiting (17%); nausea (16%); dehydration, fatigue, or diarrhea (13%, each); and thrombocytopenia or febrile neutropenia (7%, each). Sixty-six patients completed >/=2 cycles. The RR was 36% with 25 partial response (PR) and no complete responses (CRs); stable disease (SD) was 49%. Clinical benefit rate (CBR = CR + PR + SD >/=6 months) was 40%; median PFS was 4.3 months, and OS was 8.5 months.

CONCLUSIONS

DOCOX produced manageable toxicity in patients with advanced GC and AGEJ. The confirmed RR of 36%, CBR of 40%, and median survival of 8.5 months are encouraging and comparable to standard front-line regimens.

In vivo changes in gene expression profiles (GEP) after bortezomib (V) for multiple myeloma (MM): Differential effects on plasma cells (PC) and micro-environment (ME)

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Introduction: V, a proteasome inhibitor with potent anti-myeloma activity, is thought to act through effects on malignant PC and the ME. However, the in vivo effects of this drug have never been examined at the molecular level. Methods: Serial GEP analyses were performed of paired purified PC and bone marrow biopsies from 46 patients, obtained prior to and 48hr following administration of a single V dose at 1mg/m2. RNA was isolated from whole biopsies and purified PCs from each sample, converted to cRNA, and hybridized to Affymetrix U133 Plus2 microarrays. SAM analysis with 5% false discovery rate was employed to identify drug-altered genes. Results: Following V, 36 ME-associated genes (MAGs) were up-regulated, among them the osteoinductive factor osteoglycin (OGN), consistent with a V effect on osteoblastogenesis; CYR61, an angiogenesis inducer, significantly over-expressed in myeloma relative to normal marrow, was one of only 3 significantly down-regulated genes. V is known to induce expression of proteasome genes and PSMA6, PSMA1, and PSMA14 were among 15 genes up-regulated in PC. In contrast, early growth response (EGR1, EGR2, and EGR3), Krupple-like factor (KLR4, KLR5, KLR6, and KLR7) and nuclear receptor (NR4A1, NR4A2, and NR4A3) family members were down-regulated in PC by V. These differential PC and ME expression changes were only noted in low-risk MM, lacking over-expression of CKS1B. Conclusion: We report here, for the first time, on the differential molecular consequences of a single in-vivo dose of V on both tumor cells and cells of the microenvironment. The clinical implications of these findings are being further investigated and will be presented.

[Table: see text]

Phase II multicenter trial of docetaxel+oxaliplatin in stage IV gastroesophageal and/or stomach cancer

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Background: The treatment of adenocarcinoma of the gastroesophageal junction /stomach (AGEJ/S) remains a therapeutic challenge. This study was conducted to explore the efficacy and safety profile of the combination of docetaxel+oxaliplatin in patients with previously untreated advanced AGEJ/S. Docetaxel has shown significant single-agent activity and has recently been shown to increase response rates and overall survival when combined with cisplatin plus 5-FU. Oxaliplatin is associated with a more favorable safety profile compared to other platinum-based drugs (ie, cisplatin). Methods: Patients with metastatic (Stage IV) AGEJ/S were eligible. Treatment consisted of docetaxel 60 mg/m2 over 1 hour IV followed by oxaliplatin 130 mg/m2 over 2 hours on Day 1 of each 21-day cycle. Patients were treated until disease progression or unacceptable toxicity; primary endpoints are response rate, toxicity, and progression free and overall survival. Results: We have enrolled all planned eligible patients (N = 71). Baseline characteristics include a median age of 59.5 years, 72% male patients, 76% white, and ECOG PS scores 0/1/2 of 45%/49%/6%, respectively. 32.8% of patients had distal gastric cancer (fundus or pylorus). The median number of cycles delivered to date is 6 (range, 1–14). Twenty patients (31%) have required dose reductions primarily due to neutropenia. Grade 3–4 toxicities include neutropenia (69%); vomiting (17%); nausea (16%); dehydration, fatigue, and diarrhea (13%, each), and thrombocytopenia and febrile neutropenia (7%, each). Sixty-six patients have completed ≥2 cycles. The best overall confirmed response rate, by RECIST, was 24 PR (35.6%) for an overall response rate of 35.6%. Median time to response was 2.4 months and median duration of response was 4.1 months. Median survival was 9.2 months and median PFS was 4.4 months. Conclusions: The combination of docetaxel and oxaliplatin is associated with manageable toxicity in this group of patients with AGEJ/S. The best overall response rate of 35% and median survival of 9.2 months is encouraging and comparable to other standard front-line regimens. This research was supported, in part, from a research grant from sanofi-aventis.

[Table: see text]

Gene expression fingerprint of uterine serous papillary carcinoma: identification of novel molecular markers for uterine serous cancer diagnosis and therapy

Uterine serous papillary cancer (USPC) represents a rare but highly aggressive variant of endometrial cancer, the most common gynecologic tumour in women. We used oligonucleotide microarrays that interrogate the expression of some 10 000 known genes to profile 10 highly purified primary USPC cultures and five normal endometrial cells (NEC). We report that unsupervised analysis of mRNA fingerprints readily distinguished USPC from normal endometrial epithelial cells and identified 139 and 390 genes that exhibited >5-fold upregulation and downregulation, respectively, in primary USPC when compared to NEC. Many of the genes upregulated in USPC were found to represent adhesion molecules, secreted proteins and oncogenes, such as L1 cell adhesion molecule, claudin-3 and claudin-4, kallikrein 6 (protease M) and kallikrein 10 (NES1), interleukin-6 and c-erbB2. Downregulated genes in USPC included SEMACAP3, ras homolog gene family, member I (ARHI), and differentially downregulated in ovarian carcinoma gene 1. Quantitative RT-PCR was used to validate differences in gene expression between USPC and NEC for several of these genes. Owing to its potential as a novel therapeutic marker, expression of the high-affinity epithelial receptor for Clostridium perfringens enterotoxin (CPE) claudin-4 was further validated through immunohistochemical analysis of formalin-fixed paraffin-embedded specimens from which the primary USPC cultures were obtained, as well as an independent set of archival USPC specimens. Finally, the sensitivity of primary USPC to the administration of scalar doses of CPE in vitro was also demonstrated. Our results highlight the novel molecular features of USPC and provide a foundation for the development of new type-specific therapies against this highly aggressive variant of endometrial cancer.