Prospective Longitudinal Assessment of Quality of Life After Stereotactic Ablative Radiotherapy for Oligometastases: Analysis of the Population-based SABR-5 Phase II Trial

AIMS

To evaluate longitudinal patient-reported quality of life (QoL) in patients treated with stereotactic ablative radiotherapy (SABR) for oligometastases.

MATERIALS AND METHODS

The SABR-5 trial was a population-based single-arm phase II study of SABR to up to five sites of oligometastases, conducted in six regional cancer centres in British Columbia, Canada from 2016 to 2020. Prospective QoL was measured using treatment site-specific QoL questionnaires at pre-treatment baseline and at 3, 6, 9, 12, 15, 18, 21, 24, 30 and 36 months after treatment. Patients with bone metastases were assessed with the Brief Pain Inventory (BPI). Patients with liver, adrenal and abdominopelvic lymph node metastases were assessed with the Functional Assessment of Chronic Illness Therapy-Abdominal Discomfort (FACIT-AD). Patients with lung and intrathoracic lymph node metastases were assessed with the Prospective Outcomes and Support Initiative (POSI) lung questionnaire. The two one-sided test procedure was used to assess equivalence between the worst QoL score and the baseline score of individual patients. The mean QoL at all time points was used to determine the trajectory of QoL response after SABR. The proportion of patients with 'stable', 'improved' or 'worsened' QoL was determined for all time points based on standard minimal clinically important differences (MCID; BPI worst pain = 2, BPI functional interference score [FIS] = 0.5, FACIT-AD Trial Outcome Index [TOI] = 8, POSI = 3).

RESULTS

All enrolled patients with baseline QoL assessment and at least one follow-up assessment were analysed (n = 133). On equivalence testing, the patients' worst QoL scores were clinically different from baseline scores and met MCID (BPI worst pain mean difference: 1.8, 90% confidence interval 1.19 to 2.42]; BPI FIS mean difference: 1.68, 90% confidence interval 1.15 to 2.21; FACIT-AD TOI mean difference: -8.76, 90% confidence interval -11.29 to -6.24; POSI mean difference: -4.61, 90% confidence interval -6.09 to -3.14). However, the mean FIS transiently worsened at 9, 18 and 21 months but eventually returned to stable levels. The mean FACIT and POSI scores also worsened at 36 months, albeit with a limited number of responses (n = 4 and 8, respectively). Most patients reported stable QoL at all time points (range: BPI worst pain 71-82%, BPI FIS 45-78%, FACIT-AD TOI 50-100%, POSI 25-73%). Clinically significant stability, worsening and improvement were seen in 70%/13%/18% of patients at 3 months, 53%/28%/19% at 18 months and 63%/25%/13% at 36 months.

CONCLUSIONS

Transient decreases in QoL that met MCID were seen between patients' worst QoL scores and baseline scores. However, most patients experienced stable QoL relative to pre-treatment levels on long-term follow-up. Further studies are needed to characterise patients at greatest risk for decreased QoL.

Predictors of Quality of Life Decline in Patients with Oligometastases treated with Stereotactic Ablative Radiotherapy: Analysis of the Population-Based SABR-5 Phase II Trial

AIMS

Most patients experience stable quality of life (QoL) after stereotactic ablative radiotherapy (SABR) treatment for oligometastases. However, a subset of patients experience clinically relevant declines in QoL on post-treatment follow-up. This study aimed to identify risk factors for QoL decline.

MATERIALS AND METHODS

The SABR-5 trial was a population-based single-arm phase II study of SABR to up to five sites of oligometastases. Prospective QoL was measured using treatment site-specific tools at pre-treatment baseline and 3, 6, 9, 12, 15, 18, 21, 24, 30 and 36 months after treatment. The time to persistent QoL decline was calculated as the time from SABR to the first decline in QoL score meeting minimum clinically important difference with no improvement to baseline score on subsequent assessments. Univariable and multivariable logistic regression analyses were carried out to determine factors associated with QoL decline.

RESULTS

One hundred and thirty-three patients were included with a median follow-up of 32 months (interquartile range 25-43). Thirty-five patients (26%) experienced a persistent decline in QoL. The median time until persistent QoL decline was not reached. The cumulative incidence of QoL decline at 2 and 3 years were 22% (95% confidence interval 14.0-29.6) and 40% (95% confidence interval 28.0-51.2), respectively. In multivariable analysis, disease progression (odds ratio 5.23, 95% confidence interval 1.59-17.47, P = 0.007) and adrenal metastases (odds ratio 9.70, 95% confidence interval 1.41-66.93, P = 0.021) were associated with a higher risk of QoL decline. Grade 3 or higher (odds ratio 3.88, 95% confidence interval 0.92-16.31, P = 0.064) and grade 2 or higher SABR-associated toxicity (odds ratio 2.24, 95% confidence interval 0.85-5.91, P = 0.10) were associated with an increased risk of QoL decline but did not reach statistical significance.

CONCLUSIONS

Disease progression and adrenal lesion site were associated with persistent QoL decline following SABR. The development of grade 3 or higher toxicities was also associated with an increased risk, albeit not statistically significant. Further studies are needed, focusing on the QoL impact of metastasis-directed therapies.

Polymetastatic Recurrence-Free Survival in Patients with Repeat Oligometastases on the SABR-5 Trial

PURPOSE/OBJECTIVE(S)

To determine polymetastatic recurrence-free survival (PMRFS) in patients with repeat oligometastases (OM) on the SABR-5 trial.

MATERIALS/METHODS

SABR-5 is a prospective, multi-center trial that evaluated the safety of stereotactic ablative radiotherapy (SABR) in patients with 1-5 OM or oligoprogressive lesions. On SABR-5, patients were followed post-SABR according to standardized protocols. Patients with repeat extra-cranial OM after metastasis-directed therapy (MDT; SABR, surgery, or thermoablation) to all initial OM (including those treated before enrolment on SABR-5) were identified. Exclusion criteria included history of multiple primary malignancies and incomplete re-staging. PMRFS was defined as time from presentation of repeat oligometastases to death or presentation of 6 or more progressing metastases, leptomeningeal metastases, lymphangitic carcinomatosis, malignant ascites, or malignant pleural effusion. PMRFS, overall survival (OS), and progression-free survival (PFS) were calculated using the Kaplan-Meier method.

RESULTS

Seventy-six patients with repeat OM were included, of which 44 (58%) received second MDT to all OM. The most common histology in patients who received second MDT was colorectal cancer (10/44 [23%]) and in those who did not was prostate cancer (17/32 [53%]). Patients who did vs. did not receive second MDT had fewer metastases at repeat OM (mean 1.3 vs 2.2; p<0.001) and no difference in time between initial OM and repeat OM (16 vs. 17 months; p = 0.74). For patients who received second MDT, median follow-up from presentation of repeat OM was 2.6 years. Median PFS after first and second MDT were 15 months (95% CI 11-18) and 11 months (95% CI 7-17), respectively. At last follow-up, 22/44 patients (50%) were alive without polymetastatic recurrence. 3-year PMRFS and OS from presentation of repeat OM were 51% (95% CI 33-66%) and 66% (95% CI 47-79%), respectively.

CONCLUSION

Patients presenting with repeat OM after MDT may still have favorable 3-year PMRFS and OS, which may justify exploring aggressive local treatments in this subpopulation. Further randomized trials in this space are needed.

505 INTERLEUKIN-6, C-REACTIVE PROTEIN, FIBRINOGEN, AND RISK OF RECURRENCE AFTER ISCHEMIC STROKE: SYSTEMATIC REVIEW AND META-ANALYSIS

Background

Recent randomised trials showed benefit for anti-inflammatory therapies in coronary disease but excluded stroke. The prognostic value of blood inflammatory markers after stroke is uncertain and guidelines do not recommend their routine measurement for risk stratification.

Methods

We performed a systematic review and meta-analysis of studies investigating the association of C-reactive protein (CRP), interleukin-6 (IL-6) and fibrinogen and risk of recurrent stroke or major vascular events (MVEs). We searched EMBASE and Ovid Medline until 10/1/19. Random-effects meta-analysis was performed for studies reporting comparable effect measures.

Results

Of 2,515 reports identified, 39 met eligibility criteria (IL-6, n = 10; CRP, n = 33; fibrinogen, n = 16). An association with recurrent stroke was reported in 12/26 studies (CRP), 2/11 (fibrinogen) and 3/6 (IL-6). On random-effects meta-analysis of comparable studies, CRP was associated with an increased risk of recurrent stroke [pooled hazard ratio (HR) per 1 standard-deviation (SD) increase in loge-CRP (1.14, 95% CI 1.06-1.22, p &lt; 0.01)] and MVEs (pooled HR 1.21, CI 1.10-1.34, p &lt; 0.01). Fibrinogen was also associated with recurrent stroke (HR 1.26, CI 1.07-1.47, p &lt; 0.01) and MVEs (HR 1.31, 95% CI 1.15-1.49, p &lt; 0.01). Trends were identified for IL-6 for recurrent stroke (HR per 1-SD increase 1.17, CI 0.97-1.41, p = 0.10) and MVEs (HR 1.22, CI 0.96-1.55, p = 0.10).

Conclusion

Despite evidence suggesting an association between inflammatory markers and post-stroke vascular recurrence, substantial methodological heterogeneity was apparent between studies. Individual-patient pooled analysis and standardisation of methods are needed to determine the prognostic role of blood inflammatory markers and to improve patient selection for randomised trials of inflammatory therapies.

Interleukin-6, C-reactive protein, fibrinogen, and risk of recurrence after ischaemic stroke: Systematic review and meta-analysis

Background

Recent randomised trials showed benefit for anti-inflammatory therapies in coronary disease but excluded stroke. The prognostic value of blood inflammatory markers after stroke is uncertain and guidelines do not recommend their routine measurement for risk stratification.

Methods

We performed a systematic review and meta-analysis of studies investigating the association of C-reactive protein (CRP), interleukin-6 (IL-6) and fibrinogen and risk of recurrent stroke or major vascular events (MVEs). We searched EMBASE and Ovid Medline until 10/1/19. Random-effects meta-analysis was performed for studies reporting comparable effect measures.

Results

Of 2,515 reports identified, 39 met eligibility criteria (IL-6, n = 10; CRP, n = 33; fibrinogen, n = 16). An association with recurrent stroke was reported in 12/26 studies (CRP), 2/11 (fibrinogen) and 3/6 (IL-6). On random-effects meta-analysis of comparable studies, CRP was associated with an increased risk of recurrent stroke [pooled hazard ratio (HR) per 1 standard-deviation (SD) increase in log_e-CRP (1.14, 95% CI 1.06-1.22, p < 0.01)] and MVEs (pooled HR 1.21, CI 1.10-1.34, p < 0.01). Fibrinogen was also associated with recurrent stroke (HR 1.26, CI 1.07-1.47, p < 0.01) and MVEs (HR 1.31, 95% CI 1.15-1.49, p < 0.01). Trends were identified for IL-6 for recurrent stroke (HR per 1-SD increase 1.17, CI 0.97-1.41, p = 0.10) and MVEs (HR 1.22, CI 0.96-1.55, p = 0.10).

Conclusion

Despite evidence suggesting an association between inflammatory markers and post-stroke vascular recurrence, substantial methodological heterogeneity was apparent between studies. Individual-patient pooled analysis and standardisation of methods are needed to determine the prognostic role of blood inflammatory markers and to improve patient selection for randomised trials of inflammatory therapies.

Patterns of spread and prognostic implications of lung cancer metastasis in an era of driver mutations

BACKGROUND

In the present study, we examined the pattern of metastatic spread in patients with advanced non-small-cell lung cancer (nsclc) and the effect of EGFR mutations.

METHODS

Patients were identified from a provincial cancer registry, and individual medical records were reviewed. Patients were included if they had stage iv nsclc and underwent diagnostic EGFR mutation testing. Patients were divided into EGFR mutation-positive (EGFR+) and EGFR wild type (wt) cohorts. The primary endpoint was the cumulative incidence for each metastatic site: lung, bone, brain, liver, adrenal glands, distant nodes, and other. Cumulative incidence curves were estimated using a competing-risks method. The secondary outcome was survival.

RESULTS

Of the 543 identified patients, 121 (22.3%) tested as EGFR+, and 422 (77.7%) tested as EGFR wt. The incidence of brain (39.2% vs. 28.2%, p = 0.038) and lung (61.2% vs. 51.0%, p = 0.048) metastasis was higher in the EGFR+ cohort than in the EGFR wt cohort. In the EGFR+ cohort, a higher incidence of liver metastasis was associated with the exon 21 mutation subtype than with the exon 19 deletion subtype [23% vs. 7%, p < 0.01; hazard ratio (hr): 3.47]. Median survival was significantly longer for the EGFR+ cohort than for the EGFR wt cohort (22.4 months vs. 7.9 months, p < 0.001). In multivariable analysis, brain (hr: 1.73), liver (hr: 1.69), and bone (hr: 1.89) metastases were associated with worse survival.

CONCLUSIONS

Rates of lung and brain metastases are higher in EGFR mutation carriers, even when adjusted for differences in survival. Brain, liver, and bone metastases are independent negative prognostic factors for survival.

Candidate loci for insulin sensitivity and disposition index from a genome-wide association analysis of Hispanic participants in the Insulin Resistance Atherosclerosis (IRAS) Family Study

AIMS/HYPOTHESIS

The majority of type 2 diabetes genome-wide association studies (GWAS) to date have been performed in European-derived populations and have identified few variants that mediate their effect through insulin resistance. The aim of this study was to evaluate two quantitative, directly assessed measures of insulin resistance, namely insulin sensitivity index (S(I)) and insulin disposition index (DI), in Hispanic-American participants using an agnostic, high-density single nucleotide polymorphism (SNP) scan, and to validate these findings in additional samples.

METHODS

A two-stage GWAS was performed in Hispanic-American samples from the Insulin Resistance Atherosclerosis Family Study. In Stage 1, 317,000 SNPs were assessed using 229 DNA samples. SNPs with evidence of association with glucose homeostasis and adiposity traits were then genotyped on the entire set of Hispanic-American samples (n = 1,190). This report focuses on the glucose homeostasis traits: S(I) and DI.

RESULTS

Although evidence of association did not reach genome-wide significance (p = 5 x 10(-7)), in the combined analysis SNPs had admixture-adjusted p values of p (ADD) = 0.00010-0.0020 with 8 to 41% differences in genotypic means for S(I) and DI.

CONCLUSIONS/INTERPRETATION

Several candidate loci were identified that are nominally associated with S(I) and/or DI in Hispanic-American participants. Replication of these findings in independent cohorts and additional focused analysis of these loci is warranted.

Induction chemotherapy followed by concurrent chemoradiotherapy with/without esophagectomy for locally advanced esophageal squamous cell carcinoma

e15526

Background: To assess the feasibility of preoperative induction chemotherapy in addition to concurrent chemoradiotherapy (CCRT) followed by esophagectomy if possible for locally advanced esophageal squamous cell carcinoma (ESCC) with a special emphasis on M1a or nodal M1b disease. Methods: Patients who had histologic proof of T3N1M0, M1a, or nodal M1b ESCC first received up to 3 courses of induction chemotherapy (paclitaxel 70 mg/m2 or docetaxel 40 mg/m2 IV 1-hr D 1, 8; cisplatin 35 mg/m2 IV 2-hr D 1, 8; 5-fluorouracil 2000 and leucovorin 300 mg/m2 IV 24-hr D 1, 8; repeated every 28 days). This was followed by CCRT (paclitaxel 35 mg/m2 1-hr D 1, 4 /wk, cisplatin 15 mg/m2 1-hr D 2, 5/wk, and radiotherapy 2 Gy D 1–5 /wk) (Lin CC et al. Ann Oncol 18:93–8,2007). When the accumulated radiation dose reached 40 Gy, the feasibility of esophagectomy was evaluated in all patients. In patients for whom esophagectomy was not feasible, CCRT was continued to a dose of 60 Gy. Results: Fifty-six patients (M:F = 51:5, median age 58, range 41–78) with locally advanced (T3N1M0:M1a:M1b[nodal] = 30:7:19) ESCC (upper:mid:lower = 15:25:16) were enrolled from June 22, 2006 to December 17, 2008. By December 31, 2008, 10 patients are still under protocol treatment. Eighteen (T3N1:M1a:M1b[nodal] = 14:3:1) (40%) and 20 of 46 patients underwent surgery and continued CCRT up to 60 Gy, respectively. Nine (T3N1:M1a:M1b[nodal] = 7:2:0) (20%) and 5 patients had pathologic complete response and microscopic residual disease, respectively. With a median follow-up of 8.4 months (range 0.5–30.8), 17 (T3N1:M1a:M1b[nodal] = 9:2:6) patients had relapse. Four and 13 patients had local recurrence and distant metastasis, respectively. The median progression-free survival was 20.3 months. The median overall survival had not reached yet with 1- and 2-year overall survival being 76 and 57%, respectively. There was no difference in progression- free or overall survival among patients with T3N1M0, M1a, or nodal M1b disease. Conclusions: Three-step strategy of preoperative taxane-based induction chemotherapy then CCRT followed by esosphagectomy if possible appears quite active in locally advanced ESCC patients with 46% having M1a or nodal M1b disease.

No significant financial relationships to disclose.

UCSC cancer genomics browser

Abstract #2022

As experimental techniques for a comprehensive survey of the cancer landscape mature, there is a great demand in the cancer research field to develop advanced analysis and visualization tools for the characterization and integrative analysis of the large, complex genomic datasets arising from different technology platforms.&#x2028; The UCSC Cancer Genomics Browser is a suite of web-based tools designed to integrate, visualize and analyze genomic and clinical data. The secured-access browser, available at https://cancer.cse.ucsc.edu/, consists of three major components: hgHeatmap, hgFeatureSorter, and hgPathSorter. The main panel, hgHeatmap, displays a whole-genome-oriented view of genome-wide experimental measurements for individual and sets of samples/patients alongside their clinical information. hgFeatureSorter and hgPathSorter together enable investigators to order, filter, aggregate and display data interactively based on any given feature set ranging from clinical features to annotated biological pathways to user-edited collections of genes. Standard and advanced statistical tools are available to provide quantitative analysis of whole genomic data or any of its subsets. The UCSC Cancer Genomics Browser is an extension of the UCSC Genome Browser; thus it inherits and integrates the Genome Browser's existing rich set of human biology and genetics data to enhance the interpretability of cancer genomics data.&#x2028; We demonstrate the UCSC Cancer Genomics Browser by integrating several independent studies on breast cancer including the I-SPY chemotherapy clinical trial and other studies focused on chemotherapeutic response or long-term survival. The types of data that are visualized and analyzed by the browser include microarray measurements of gene expression, copy number variation and phosphoprotein expression, MRI imaging measurements, and clinical parameters.&#x2028; Collectively, these tools facilitate a synergistic interaction among clinicians, experimental biologists, and bioinformaticians. They enable cancer researchers to better explore the breadth and depth of the cancer genomics data resources, and to further characterize molecular pathways that influence cellular dynamics and stability in cancer. Ultimately, insights gained by applying these tools may advance our knowledge of human cancer biology and stimulate the discovery of new prognostic and diagnostic markers, as well as the development of therapeutic and prevention strategies.&#x2028; Funding sources: CALGB CA31964 and CA33601, ACRIN U01 CA079778 and CA080098, NCI SPORE CA58207, California Institute for Quantitative Biosciences, NHGRI.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 2022.

The UCSC Genome Browser Database: update 2009

The UCSC Genome Browser Database (GBD, http://genome.ucsc.edu) is a publicly available collection of genome assembly sequence data and integrated annotations for a large number of organisms, including extensive comparative-genomic resources. In the past year, 13 new genome assemblies have been added, including two important primate species, orangutan and marmoset, bringing the total to 46 assemblies for 24 different vertebrates and 39 assemblies for 22 different invertebrate animals. The GBD datasets may be viewed graphically with the UCSC Genome Browser, which uses a coordinate-based display system allowing users to juxtapose a wide variety of data. These data include all mRNAs from GenBank mapped to all organisms, RefSeq alignments, gene predictions, regulatory elements, gene expression data, repeats, SNPs and other variation data, as well as pairwise and multiple-genome alignments. A variety of other bioinformatics tools are also provided, including BLAT, the Table Browser, the Gene Sorter, the Proteome Browser, VisiGene and Genome Graphs.

The UCSC Genome Browser Database: 2008 update

The University of California, Santa Cruz, Genome Browser Database (GBD) provides integrated sequence and annotation data for a large collection of vertebrate and model organism genomes. Seventeen new assemblies have been added to the database in the past year, for a total coverage of 19 vertebrate and 21 invertebrate species as of September 2007. For each assembly, the GBD contains a collection of annotation data aligned to the genomic sequence. Highlights of this year's additions include a 28-species human-based vertebrate conservation annotation, an enhanced UCSC Genes set, and more human variation, MGC, and ENCODE data. The database is optimized for fast interactive performance with a set of web-based tools that may be used to view, manipulate, filter and download the annotation data. New toolset features include the Genome Graphs tool for displaying genome-wide data sets, session saving and sharing, better custom track management, expanded Genome Browser configuration options and a Genome Browser wiki site. The downloadable GBD data, the companion Genome Browser toolset and links to documentation and related information can be found at: http://genome.ucsc.edu/.

The UCSC genome browser database: update 2007

The University of California, Santa Cruz Genome Browser Database contains, as of September 2006, sequence and annotation data for the genomes of 13 vertebrate and 19 invertebrate species. The Genome Browser displays a wide variety of annotations at all scales from the single nucleotide level up to a full chromosome and includes assembly data, genes and gene predictions, mRNA and EST alignments, and comparative genomics, regulation, expression and variation data. The database is optimized for fast interactive performance with web tools that provide powerful visualization and querying capabilities for mining the data. In the past year, 22 new assemblies and several new sets of human variation annotation have been released. New features include VisiGene, a fully integrated in situ hybridization image browser; phyloGif, for drawing evolutionary tree diagrams; a redesigned Custom Track feature; an expanded SNP annotation track; and many new display options. The Genome Browser, other tools, downloadable data files and links to documentation and other information can be found at .

The UCSC Genome Browser Database: update 2006

The University of California Santa Cruz Genome Browser Database (GBD) contains sequence and annotation data for the genomes of about a dozen vertebrate species and several major model organisms. Genome annotations typically include assembly data, sequence composition, genes and gene predictions, mRNA and expressed sequence tag evidence, comparative genomics, regulation, expression and variation data. The database is optimized to support fast interactive performance with web tools that provide powerful visualization and querying capabilities for mining the data. The Genome Browser displays a wide variety of annotations at all scales from single nucleotide level up to a full chromosome. The Table Browser provides direct access to the database tables and sequence data, enabling complex queries on genome-wide datasets. The Proteome Browser graphically displays protein properties. The Gene Sorter allows filtering and comparison of genes by several metrics including expression data and several gene properties. BLAT and In Silico PCR search for sequences in entire genomes in seconds. These tools are highly integrated and provide many hyperlinks to other databases and websites. The GBD, browsing tools, downloadable data files and links to documentation and other information can be found at .

Immunoprofile of cervical and endometrial adenocarcinomas using a tissue microarray

Adenocarcinomas of the uterine cervix show a wide range of morphological features, and can be confused with endometrial adenocarcinoma in biopsy or curetting specimens. The objective of this study was to use tissue microarray technology to evaluate the immunoprofile of a large set of uterine adenocarcinomas with an extended panel of antibodies, comparing the profile of primary cervical and endometrial adenocarcinomas. A tissue microarray was constructed using paraffin-embedded, formalin-fixed tissues from 141 hysterectomy specimens. Duplicate 0.6-mm cores were obtained from 57 cervical adenocarcinomas (16 in situ and 41 invasive) and 84 endometrial adenocarcinomas. Tissue array sections were immunostained with 21 commercially available antibodies [B72.3, CD 99, carcinoembryonic antigen (CEA), c-kit, pancytokeratin, CK 5/6, CK 7, CK8/18, CK19, CK 20, CK 22, EMA, estrogen receptor (ER), KP-1, melan-A, p53, PLAP, S-100, synaptophysin, TTF-1, and vimentin] utilizing the avidin-biotin (ABC) technique. Hierarchical clustering analysis of the tumors was done based on the immunostaining results. Only ER ( P<0.001), CEA ( P=0.04), vimentin ( P<0.001), and CK 8/18 ( P=0.002) showed a significantly different frequency of positivity in endometrial relative to cervical adenocarcinomas. ER, vimentin, and CK 8/18 were more likely to be expressed in endometrial adenocarcinomas, while cervical adenocarcinomas more frequently expressed CEA. We were able to identify immunoprofiles that were highly specific for endocervical adenocarcinoma (ER(-), vimentin(-), CK 8/18(-), CEA(+)) or endometrial adenocarcinoma (ER(+), vimentin(+), CK 8/18(+), CEA(-)), but most tumors showed an intermediate, non-specific immunophenotype. Hierarchical clustering analysis was useful in the interpretation of these intermediate immunophenotypes. Papillary serous adenocarcinoma of the endometrium was less likely to express vimentin ( P=0.002) than endometrioid carcinoma of the endometrium.

Pancreatic beta-cell alpha2A adrenoceptor and phospholipid changes in hyperlipidemic rats

We previously showed that a 48-h intravenous lipid infusion in rats induces pancreatic beta-cell hypersensitivity to catecholamines. Our aim was to study the lipid-related changes that may account for such hypersensitivity in pancreatic islets. We show here that a 48-h increase in plasma FFA alters the binding characteristics of beta-cell alpha2 adrenoceptors in rats. Lipid infusion decreases pancreatic norepinephrine (NE) turnover rate by 28%, reflecting a reduction of pancreatic NE stores. Following lipid infusion, the density of alpha2 adrenoceptor binding sites is significantly lower and receptor affinity higher, both in islet homogenates (by three- and fivefold, respectively) and isolated whole beta-cells (by two- and sixfold, respectively). These changes correlate with the elevated insulin response to glucose found in lipid-infused rats. We also found a modification of islet phospholipid content, particularly in phosphoethanolamine species containing infused FA such as palmitate, oleate, stearate, and linoleate. This may account for the modifications in receptor affinity. These results suggest that hyperlipidemia-associated pathologies such as diabetes and obesity not only may result from alterations of metabolic pathways but also may be a consequence of early modifications in nervous firing rates and signal transduction pathways.

Exogenous peptide and protein expression levels using retroviral vectors in human cells

Pseudotyped retroviral vectors combine the advantages of broad host range, high expression, stable chromosomal integration, and ease of preparation. These vectors greatly facilitate delivery into mammalian cells of sequences encoding individual peptide inhibitors-including those with therapeutic utility-and inhibitor libraries. However, retroviral vectors vary in behavior, particularly with respect to expression levels in different cell lines. Expression level is especially important in transdominant experiments because the concentration of an inhibitor (for example, an expressed peptide) is one of the key determinants in the degree of complex formation between the inhibitor and its target. Thus, inhibitor concentration should have an impact on the expressivity and/or penetrance of an induced phenotype. Here, we compare several retroviral vectors and human cell lines for relative expression levels using a green fluorescent protein reporter. We show for a subset of these lines that cellular protein concentrations produced by single-copy vectors range up to about 2 microM. We also examine other variables that contribute to expression level, such as the nature of the expressed protein's carboxy terminus. Finally, we test the effect of increased concentration on phenotype with a nine-amino-acid peptide derived from the human papilloma virus protein E7 which overcomes E7-mediated cell growth.

Template selection during manipulation of complex mixtures by PCR

PCR is ubiquitous in molecular biology. It is used to amplify single sequences from large genomes, or populations of sequences from complex mixtures such as cDNA libraries in mammalian cells. These cDNA libraries are often employed in subsequent labor-intensive experiments such as genetic screens, the outcome of which depends on library quality. The use of PCR to amplify diverse sequence populations raises important technical issues. One question is whether or not PCR is capable of maintaining population diversity, specifically with respect to template selection in the first rounds of the amplification process (i.e., the possibility that rare sequences in a complex mixture are lost because of amplification failure at the outset of the PCR). Here, we analyze the properties of PCR in the context of template selection in complex mixtures and show that it is an excellent method for preserving diversity.

A case-control study of tobacco and alcohol consumption in Leber hereditary optic neuropathy

PURPOSE

To determine if tobacco or alcohol consumption is associated with vision loss among sibships harboring pathogenic mitochondrial mutations associated with Leber hereditary optic neuropathy.

METHODS

Retrospective case-control study with questionnaires obtained from both affected and unaffected siblings from 80 sibships with Leber hereditary optic neuropathy. Sibships harbored molecularly confirmed mitochondrial DNA mutations at nucleotide positions 11778 (63), 14484 (10), and 3460 (7). Exposure in affected individuals was calculated based on reported consumption before vision loss.

RESULTS

For male probands (67 sibships), the recurrence risk within a sibship was 10.3% (eight of 78) for males and 3.1% (three of 98) for females. For female probands (13 sibships), the recurrence risk within a sibship was 17.6% (three of 17) for males and 0% (zero of 22) for females. Greater risk of vision loss was associated with male sex (odds ratio [OR] = 6.63; 95% confidence interval [CI] = 2.96 to 14.84; P =.00001) and harboring a 3460 or 14484 in comparison with the 11778 mutation (OR = 2.071; 95% CI = 1.19 to 3.58; P =.0095). No significant association of maximal intensity of smoking or cumulative smoking, whether light or heavy, with vision loss was observed. Light (OR = 0. 31; 95% CI = 0.17 to 0.56; P =.0001) and heavy alcohol consumers (OR = 0.25; 95% CI = 0.11 to 0.58; P =.0011) were less likely to be affected than individuals who did not consume alcohol after adjusting for age, sex, and mutation. In a categorical analysis of sibships with the 3460 or 14484 mutation, no relationship of vision loss with tobacco or alcohol consumption was observed.

CONCLUSION

Unlike previous studies, the present study calculated exposure based on self-reported consumption of tobacco or alcohol before vision loss. No significant deleterious association between tobacco or alcohol consumption and vision loss among individuals harboring Leber hereditary optic neuropathy mutations was observed. Tobacco and alcohol do not appear to promote vision loss in Leber hereditary optic neuropathy.

Electrospray ionization mass spectrometric analyses of phospholipids from INS-1 insulinoma cells: comparison to pancreatic islets and effects of fatty acid supplementation on phospholipid composition and insulin secretion

Insulin secretion by pancreatic islet beta-cells is impaired in diabetes mellitus, and normal beta-cells are enriched in phospholipids with arachidonate as sn-2 substituent. Such molecules may play structural roles in exocytotic membrane fusion or serve as substrates for phospholipases activated by insulin secretagogues. INS-1 insulinoma cells respond to secretagogues and permit the study of effects of culture with free fatty acids on phospholipid composition and secretion. INS-1 cell glycerophosphocholine (GPC) and glycerophosphoethanolamine (GPE) lipids are demonstrated here by electrospray ionization mass spectrometry to contain a lower fraction of molecules with arachidonate and a higher fraction with oleate as sn-2 substituent than native islets. Palmitic acid supplementation induces little change in these INS-1 cell lipids, but supplementation with linoleate or arachidonate induces a large rise in the fraction of INS-1 cell GPC species with polyunsaturated sn-2 substituents and a fall in oleate-containing species to yield a GPC profile similar to native islets. The fraction of GPE lipids comprised of plasmenylethanolamine species with polyunsaturated sn-2 substituents in early-passage INS-1 cells is similar to that of islets, but declines on serial passage. Such molecules might participate in exocytotic membrane fusion, and late-passage INS-1 cells have reduced insulin secretory responses. Arachidonate supplementation induces a rise in the fraction of INS-1 cell GPE lipids with polyunsaturated sn-2 substituents and partially restores responses to insulin secretagogues by late-passage INS-1 cells, but does not further amplify secretion by early-passage cells. Effects of extracellular free fatty acids on beta-cell phospholipid composition and secretory responses could be involved in changes in beta-cell function during the period of hyper-free fatty acidemia that precedes diabetes mellitus.

Subdural empyema complicating cerebrospinal fluid shunt infection

Subdural empyema has not been reported previously as a complication of cerebrospinal fluid (CSF) shunt surgery. An infant submitted to CSF shunt insertion for congenital hydrocephalus developed subdural empyema after a failed attempt to treat a superficial scalp wound infection with oral antibiotics. Enterobacter cloacae was isolated from the empyema. Temporizing management of the preceding superficial wound infection with oral antibiotics probably was the cause of this exotic pathogen. The treatment of infected scalp wounds contiguous with shunt hardware must be surgical.

Intrarenal insulin-like growth factor-1 axis after unilateral nephrectomy in rat

It has been suggested that insulin-like growth factor-1 (IGF-1) may play a role in early compensatory renal growth. Since IGF-1 action is influenced by IGF binding proteins (IGFBP), this study was conducted to characterize the changes in gene expression not only of IGF-1 and its receptor, but also of IGFBP in the hypertrophying kidney of adult and weanling rats 1 wk after removal of the other kidney. At this time, there were distinct age-dependent changes in the renal IGF-1 axis. In the mature kidney, IGF-1 mRNA levels fell without a change in kidney IGF-1 peptide content. Likewise, although IGFBP-2, -3, and -5 mRNA levels fell, membrane-associated IGFBP did not change. IGF-1 receptor mRNA levels and IGF-1 receptor number both fell. In the weanling kidneys, IGF-1 mRNA and peptide levels and IGF-1 receptor binding were unaltered. However, IGFBP-3, -4, and -5 mRNA levels were increased, as were plasma membrane-associated IGFBP. Although these changes in the intrarenal IGF-1 axis were distinct, it is difficult to conceive how in either the mature or immature rat they could contribute to the ongoing compensatory renal growth that occurs 1 wk after loss of kidney mass unless IGF-1 were acting in a synergistic manner with other growth promoters.

Effects of changes in three catalytic residues on the relative stabilities of some of the intermediates and transition states in the citrate synthase reaction

This work reports the relative importance of the interactions provided by three catalytic residues to individual steps in the mechanism of citrate synthase. When the side chains of any of the residues (H320, D375, and H274) are mutated, the data indicate that they are involved in the stabilization of one or more of the transition/intermediate states in the multistep citrate synthase reaction. H320 forms a hydrogen bond with the carbonyl of oxaloacetate and the alcohols of the citryl-coenzyme A and citrate products. Enzymes substituted at H320 (Q, G, N, and R) have reaction profiles for which the condensation reaction is cleanly rate determining. None of these mutants can activate the carbonyl of oxaloacetate by polarization. All these mutants catalyze the necessary proton transfer from the methyl group of acetyl-coenzyme A only poorly, a process which occurs in a structurally separate site. Furthermore, all H320 mutants hydrolyze the citryl-coenzyme A intermediate significantly more slowly than does the wild-type. D375 is the base removing the proton of acetyl-coenzyme A. D375E and D375G have greatly diminished ability to catalyze proton transfer from acetyl-CoA. The D375 mutants polarize the oxaloacetate carbonyl as well as wild-type. For D375E, the hydrolysis of citryl-CoA is rate determining. D375G, having no side chain capable of acid-base chemistry in either the condensation or hydrolysis reactions is nearly completely devoid of activity in any of the reactions catalyzed by the wild-type. H274 hydrogen bonds to the carbonyl of acetyl-coenzyme A but also forms the back wall of the oxaloacetate-binding site. H274G cannot properly activate either oxaloacetate or acetyl-coenzyme A, and the condensation reaction is overwhelmingly rate determining. Nonetheless, hydrolysis of the intermediate is impaired. All the enzymes except H320R and H274G show kinetic cooperativity with CitCoA as substrate, indicating changes in the subunit interactions with these latter two mutants. The energetics of citrate synthase are surprisingly tightly coupled. All changes affect more than one step in the catalytic cycle. Within the condensation reaction, the intermediate of proton transfer must occupy a shallow well between transition states close in free energy so that perturbations of one have substantial effects on that of the other.

The insulin-like growth factor-I axis in acute renal failure

We have examined the response of the renal insulin-like growth factor (IGF-I) axis to acute ischemic injury in the rat Key findings included a decrease in IGF-I mRNA and peptide levels, a decrease in GH receptor gene plus protein expression and a decrease in the IGF binding proteins except for IGF binding protein I. Administration of GH to compensate for the reduced GH receptor binding corrected the IGF-I mRNA levels suggesting a relative GH deficiency. Interestingly, IGF-I receptor mRNA levels were unchanged while plasma membrane IGF-I receptor number increased two fold. This appeared to be due to a redistribution of receptors to a membrane location. IGF-I receptor autophosphorylation and tyrosine kinase activity were intact despite severe uremia for up to 6 days. We propose that this increase of functional IGF-I receptors following acute tubular necrosis will sensitize the kidney to the administration of exogenous IGF-I.

Urinary mutagenicity as a biomarker in workers exposed to benzidine: correlation with urinary metabolites and urothelial DNA adducts

Urinary mutagenicity has been used in occupational and epidemiological studies for over two decades as a cost-effective, general biomarker of exposure to genotoxic agents. However, few studies have compared urinary mutagenicity to additional biomarkers determined among low- and high-exposed groups. To address this issue, we evaluated the relationship between urinary mutagenicity and other types of biomarkers in a cross-sectional study involving 15 workers exposed to the urinary bladder carcinogen benzidine (BZ, high exposure), 15 workers exposed to BZ-dyes (low exposure), and 13 unexposed controls in Ahmedabad, India. Urinary organics were extracted by C18/methanol and evaluated for mutagenicity in the presence of S9 in the Salmonella strain YG1024, which is a frameshift strain that overproduces acetyltransferase. The results were compared to biomarker data reported recently from the same urine samples (Rothman et al., Proc. Natl Acad. Sci. USA, 93, 5084-5089, 1996) that included a metabolite biomarker (the sum of the urinary levels of BZ + N-acetylbenzidine + N,N'-diacetylbenzidine) and a DNA adduct biomarker [a presumptive N-(3'-phosphodeoxyguanosin-8-yl)-N'-acetylbenzidine (C8dG-ABZ) DNA adduct in exfoliated urothelial cells]. The mean +/- SE urinary mutagenicity (revertants/micromol of creatinine) of the low-exposure (BZ-dye) workers was 8.2 +/- 2.4, which was significantly different from the mean of the controls (2.8 +/- 0.7, P = 0.04) as was that of the mean of the high-exposure (BZ) workers (123.2 +/- 26.1, P < 0.0001). Urinary mutagenicity showed strong, positive correlations with urinary metabolites (r = 0.88, P < 0.0001) and the level of the presumptive C8dG-ABZ urothelial DNA adduct (r = 0.59, P = 0.0006). A strong association was found between tobacco use (bidi smoking) and urinary mutagenicity among the controls (r = 0.68, P = 0.01) but not among the exposed workers (r = 0.18, P = 0.11). This study confirms the ability of a biomarker such as urinary mutagenicity to detect low-dose exposures, identify additional genotoxic exposures among the controls, and correlate strongly with urinary metabolites and DNA adducts in the target tissue (urinary bladder epithelia) in humans.