Global rewiring of lipid metabolism to produce carotenoid by deleting the transcription factor genes ino2/ino4 in Saccharomyces cerevisiae

The transcription factor complex INO2 and INO4 in Saccharomyces cerevisiae plays a vital role in lipid biosynthesis by activating multiple genes in the biosynthetic pathways of phospholipid, fatty acid, and sterol. Previous studies have reported conflicting results regarding the effects of ino2 and ino4 gene expression levels on target chemicals. Therefore, this study aimed to examine the influence of different ino2 and ino4 expression levels on carotenoid production (e.g., lycopene), which shares a common precursor, acetyl-CoA, with lipid metabolism. Surprisingly, 2.6- and 1.8-fold increase in lycopene yield in the ino2 and ino4 deletion strains were found, respectively. In contrast, ino2 overexpression did not promote lycopene accumulation. Additionally, there was a decrease in intracellular free fatty acids in the ino2 deletion strain. Comparative transcriptome analysis revealed a significant downregulation of genes related to lipid biosynthesis in the ino2 deletion strain. To our knowledge, this is the first report showing that deletion of transcription factor genes ino2 and ino4 can facilitate lycopene accumulation. These findings hold significant implications for the development of metabolically engineered S. cerevisiae with enhanced carotenoid production.

Design of a dual-responding genetic circuit for high-throughput identification of L-threonine-overproducing Escherichia coli

L-threonine is a crucial amino acid that is extensively employed in the realms of food, animal feed and pharmaceuticals. Unfortunately, the lack of an appropriate biosensor has hindered the establishment of a robust high-throughput screening (HTS) system for the identification of the desired strains from random mutants. In this study, a dual-responding genetic circuit that capitalizes on the L-threonine inducer-like effect, the L-threonine riboswitch, and a signal amplification system was designed for the purpose of screening L-threonine overproducers. This platform effectively enhanced the performance of the enzyme and facilitated the identification of high L-threonine-producing strains from a random mutant library. Consequently, pathway optimization and directed evolution of the key enzyme enhanced L-threonine production by 4 and 7-fold, respectively. These results demonstrate the potential of biosensor design for dynamic metabolite detection and offer a promising tool for HTS and metabolic regulation for the development of L-threonine-hyperproducing strains.

Engineering a Balanced Acetyl Coenzyme A Metabolism in Saccharomyces cerevisiae for Lycopene Production through Rational and Evolutionary Engineering

Saccharomyces cerevisiae is increasingly being used for the production of chemicals derived from acetyl coenzyme A (acetyl-CoA). However, the inadequate supply of cytosolic acetyl-CoA often leads to low yields. Here, we developed a novel strategy for balancing acetyl-CoA metabolism and increasing the amount of the downstream product. First, the combination of acetaldehyde dehydrogenase (eutE) and acetoacetyl-CoA thiolase (AtoB) was optimized to redirect the acetyl-CoA flux toward the target pathway, with a 21-fold improvement in mevalonic acid production. Second, pathway engineering and evolutionary engineering were conducted to attenuate the growth deficiency, and a 10-fold improvement of the maximum productivity was achieved. Third, acetyl-CoA carboxylase (ACC₁) was dynamically downregulated as the complementary acetyl-CoA pathway, and the yield was improved more than twofold. Fourth, the most efficient and complementary acetyl-CoA pathways were combined, and the final strain produced 68 mg/g CDW lycopene, which was among the highest yields reported in S. cerevisiae. This study demonstrates a new method of producing lycopene products by regulating acetyl-CoA metabolism.

Biophysical analysis of gelatin and PLGA nanoparticle interactions with complex biomimetic lung surfactant models

Biocompatible materials are increasingly used for pulmonary drug delivery, and it is essential to understand their potential impact on the respiratory system, notably their effect on lung surfactant, a monolayer of lipids and proteins, responsible for preventing alveolar collapse during breathing cycles. We have developed a complex mimic of lung surfactant composed of eight lipids mixed in ratios reported for native lung surfactant. A synthetic peptide based on surfactant protein B was added to better mimic the biological system. This model was used to evaluate the impact of biocompatible gelatin and poly(lactic-co-glycolic acid) nanoparticles. Surface pressure–area isotherms were used to assess lipid packing, film compressibility and stability, whereas the lateral organization was visualized by Brewster angle microscopy. Nanoparticles increased film fluidity and altered the monolayer collapse pressure. Bright protruding clusters formed in their presence indicate a significant impact on the lateral organization of the surfactant film. Altogether, this work indicates that biocompatible materials considered to be safe for drug delivery still need to be assessed for their potential detrimental impact before use in therapeutic applications

Biodegradable nanoparticles drastically alters lateral organization of lung surfactant lipid- peptide model system.

Toll-like receptor 2 costimulation potentiates the antitumor efficacy of CAR T Cells

Chimeric antigen receptor (CAR) T-cell immunotherapies have shown unprecedented success in treating leukemia but limited clinical efficacy in solid tumors. Here, we generated 1928zT2 and m28zT2, targeting CD19 and mesothelin, respectively, by introducing the Toll/interleukin-1 receptor domain of Toll-like receptor 2 (TLR2) to 1928z and m28z. T cells expressing 1928zT2 or m28zT2 showed improved expansion, persistency and effector function against CD19⁺ leukemia or mesothelin⁺ solid tumors respectively in vitro and in vivo. In a patient with relapsed B-cell acute lymphoblastic leukemia, a single dose of 5 × 10⁴/kg 1928zT2 T cells resulted in robust expansion and leukemia eradication and led to complete remission. Hence, our results demonstrate that TLR2 signaling can contribute to the efficacy of CAR T cells. Further clinical trials are warranted to establish the safety and efficacy of this approach.

Modeling Current Density Maps Using Aliev-Panfilov Electrophysiological Heart Model

Most existing studies of cardiac arrhythmia rely on surface measurements through optical or electrical mapping techniques. Current density imaging (CDI) is a method which enables us to study current pathways inside the tissue. However, this method entails implementation complexities for beating ex vivo hearts. Hence, this work presents an approach to simulate and study the current distributions in different cardiac electrophysiological states. The results are corroborated by experimental data, and they indicate that different states were distinguishable. The CDI simulations can be used for studying cardiac arrhythmias under simulation conditions which are otherwise impossible or difficult to be implemented experimentally.

Palliative chemotherapy in advanced colorectal cancer patients 80 years of age and older

BACKGROUND

Colorectal cancer (crc) has a median diagnostic age of 68 years. Despite significant progress in chemotherapy (ctx) options, few data on outcomes or toxicity from ctx in patients 80 years of age and older are available. We investigated ctx in such patients with metastatic crc (mcrc), hypothesizing high rates of hospitalization and toxicity.

METHODS

A retrospective chart review identified patients 80 years of age and older with mcrc who initiated ctx between 2005-2010 at our institution. Patient demographics and ctx data were collected. Endpoints included rates of hospitalization, ctx discontinuation because of toxicity, and overall survival.

RESULTS

In 60 patients, ctx was initiated on 88 occasions. Median age in the cohort was 83 years; 52% were men; 72% lived with family; 53% had a modified Charlson comorbidity index of 2 or greater; and 31% were taking 6 or more prescription medications at baseline. At baseline, 33% of the patients were anemic (hemoglobin < 100 g/L), 36% had leukocytosis (white blood cells > 11×10(9)/L), and 48% had renal impairment (estimated glomerular filtration rate < 60 mL/min/1.73 m(2)). In 53%, ctx was given as first-line treatment. The initial ctx dose was adjusted in 67%, and capecitabine was the most common chemotherapeutic agent (45%). In 19 instances (22%), the patient was hospitalized during or within 30 days of ctx; in 26 instances (30%), the ctx was discontinued because of toxicity, and in 48 instances (55%), the patient required at least 1 dose reduction, omission, or delay. Median overall survival was 17.8 months (95% confidence interval: 14.3 to 20.8 months).

CONCLUSIONS

In the population 80 years of age and older, ctx for mcrc is feasible; however, most recipients will require dose adjustments, and a significant proportion will be hospitalized or stop ctx because of toxicity. Prospective research incorporating geriatric assessment tools is required to better select these older patients for ctx.

Fusion of structural and functional cardiac magnetic resonance imaging data for studying ventricular fibrillation

Magnetic Resonance Imaging (MRI) techniques such as Current Density Imaging (CDI) and Diffusion Tensor Imaging (DTI) provide a complementing set of imaging data that can describe both the functional and structural states of biological tissues. This paper presents a Joint Independent Component Analysis (jICA) based fusion approach which can be utilized to fuse CDI and DTI data to quantify the differences between two cardiac states: Ventricular Fibrillation (VF) and Asystolic/Normal (AS/NM). Such an approach could lead to a better insight on the mechanism of VF. Fusing CDI and DTI data from 8 data sets from 6 beating porcine hearts, in effect, detects the differences between two cardiac states, qualitatively and quantitatively. This initial study demonstrates the applicability of MRI-based imaging techniques and jICA-based fusion approach in studying cardiac arrhythmias.

A novel approach to quantification of real and artifactual components of current density imaging for phantom and live heart

Spatial distribution of injected current in a subject could be calculated and visualized through current density imaging (CDI). Calculated CDI paths however have a limited degree of accuracy due to both avoidable methodological errors and inevitable limitations dictated by MR imaging constraints. The source and impact of these limitations are scrutinized in this paper. Quantification of such limitations is an essential step prior to passing any judgment about the results especially in biomedical applications. An innovative technique along with metrics for evaluation of range of errors using baseline and phase cycle MR images is proposed in this work. The presented approach is helpful in pinpointing the local artifacts (areas for which CDI results are suspect), evaluation of global noises and artifacts and assessment of the effect of approximation algorithms on real and artifactual components. We will demonstrate how this error/reliability evaluation is applicable to interpretation of CDI results and in this framework, report the CDI results for an artificial phantom and a live pig heart in Langendorff setup. It is contended here that using this method, the inevitable trade-off between details and approximations of CDI components could be monitored which provides a great opportunity for robust interpretation of results. The proposed approach could be extended, adapted and used for statistical analysis of similar methods which aim at mapping current and impedance based on magnetic flux images obtained through MRI.

Dose heterogeneity correction for low-energy brachytherapy sources using dual-energy CT images

Permanent seed implant brachytherapy is currently used for adjuvant radiotherapy of early stage prostate and breast cancer patients. The current standard for calculation of dose around brachytherapy sources is based on the AAPM TG-43 formalism, which generates the dose in a homogeneous water medium. Recently, AAPM TG-186 emphasized the importance of accounting for tissue heterogeneities. We have previously reported on a methodology where the absorbed dose in tissue can be obtained by multiplying the dose, calculated by the TG-43 formalism, by an inhomogeneity correction factor (ICF). In this work we make use of dual energy CT (DECT) images to extract ICF parameters. The advantage of DECT over conventional CT is that it eliminates the need for tissue segmentation as well as assignment of population based atomic compositions. DECT images of a heterogeneous phantom were acquired and the dose was calculated using both TG-43 and TG-43 [Formula: see text] formalisms. The results were compared to experimental measurements using Gafchromic films in the mid-plane of the phantom. For a seed implant configuration of 8 seeds spaced 1.5 cm apart in a cubic structure, the gamma passing score for 2%/2 mm criteria improved from 40.8% to 90.5% when ICF was applied to TG-43 dose distributions.

Manual cataract extraction via a subconjunctival limbus oblique incision for mature cataracts

Aims:

To report the technique and outcomes of sutureless manual cataract extraction via a subconjunctival limbus oblique incision for mature cataracts.

Materials and Methods:

This retrospective study comprised of 112 eyes of 83 patients with mature cataract who all had manual cataract extraction via a subconjunctival limbus oblique incision. A transconjunctival tunnel is fashioned with a 3.0 mm keratome, 0.5 mm behind the limbal vascular arcades. A limbal tunnel, with a transverse extent of 9 mm in the cornea and 7.0 mm in the limbus, is created beneath the conjunctival/Tenon's tissue using an angled bevel-up crescent blade. Outcome measures included visual acuity, intraoperative complications, surgically induced astigmatism, endothelial cell loss rate and surgery time.

Results:

Self-sealing wound was achieved in 112 eyes (98.2%). The nucleus was delivered in whole in 108 eyes (96.4%). Intraoperative complications included hyphema in 3 eyes (2.7%), iridodialysis in 2 eyes 1.8%), posterior capsular rupture and zonular dialysis in 2 eyes (1.8%). At the 3-month follow-up, 91% patients achieved a best-corrected visual acuity of 20/20 or better, the mean of surgically induced astigmatism was -0.62 ± 0.41 Diopters and endothelial cell loss was 4.2%. Average surgical time was 3.75 min per case.

Conclusion:

This subconjunctival limbus oblique incision has the potential to serve as safe and effective technique for mature cataracts.

mTORC1/2 targeted by n-3 polyunsaturated fatty acids in the prevention of mammary tumorigenesis and tumor progression

Although epidemiological and preclinical studies have shown the preventative effects of n-3 polyunsaturated fatty acids (PUFAs) on breast cancer, inconsistencies still remain in the data and the underlying mechanisms remain unclear. In this study, we identified mammalian target of rapamycin (mTOR) signaling, which plays an essential role in cell proliferation and breast tumorigenesis, as a target of n-3 PUFAs. In breast cancer cell lines, n-3 PUFAs rapidly and efficiently suppress both mTOR complex 1 (mTORC1) and mTORC2 and their downstream signaling, and subsequently inhibit cell proliferation and angiogenesis while promoting apoptosis. Further study indicates that stabilization of the mTOR-raptor complex by n-3 PUFAs may contribute to their inhibitory effect on mTORC1. Importantly, four complementary and well-controlled animal models were utilized to identify the role and molecular target of n-3 PUFAs in the prevention of breast carcinogenesis and progression, namely: (1) chemically induced mammary tumor rats with a high dietary intake of n-3 PUFAs; (2) nude mice implanted with mammary tumor cell lines stably expressing fat-1, a desaturase that catalyzes the conversion of n-6 to n-3 PUFAs and produces n-3 PUFAs endogenously; (3) fat-1 transgenic severe combined immune deficiency mice implanted with breast tumor cells; and (4) the fat-1 transgenic mouse mammary tumor virus-polyoma virus middle T oncogene double-hybrid mice, a model of aggressive breast cancer. In summary, dietary and endogenous n-3 PUFAs abrogate the activity of mTORC1/2 pathways in vitro and in vivo and prevent breast carcinogenesis, tumor growth and metastasis. Taken together, our findings convincingly clarify the causal relationship between n-3 PUFAs and breast cancer prevention and establish mTORC1/2 as a target of n-3 PUFAs.

Using Video Acquired from an Unmanned Aerial Vehicle (UAV) to Measure Fracture Orientation in an Open-Pit Mine

This project explored the feasibility of using video images acquired with an unmanned aerial vehicle (UAV) to obtain three-dimensional (3D) point clouds using structure from motion (SfM) software. Missions were flown using an Aeryon Scout: a lightweight, vertical take-off and landing quadrotor micro UAV with a miniature video camera. The initial mission captured urban scene images that were used to assess system performance while the main mission focused on rock walls where 3D images were used to successfully measure fracture orientations. Point clouds generated from this combination of technologies were sparse, but in the future, improvements in the resolution of original video images would cascade through the processing and improve the overall results. Such a system could have a multitude of applications in the mining industry, contributing to both safety and financial considerations.

Polymorphism of the melatonin receptor genes and its relationship with seasonal reproduction in the Gulin Ma goat breed

Melatonin is thought to be the main molecule that transmits the signal of seasonal change to the neuroendocrine system in seasonal breeding species. Melatonin exerts its effects through specific melatonin receptors, MTNR1A and MTNR1B. In the present study, six native goat breeds in China and one introduced goat breed were analysed to investigate the relationship between the genetic polymorphism of receptor genes and seasonal reproduction. Sequencing results showed that there were five polymorphic mutations in the MTNR1A gene and two in the MTNR1B gene. In the MTNR1A gene, genotypes AA, AB and BB for 424C>T and genotypes CC, CD and DD for 589C>A were observed in these goat breeds. In all six native goat breeds, only genotype AA was detected. In the MTNR1B gene, genotypes EE, EF and FF for 1179G>A and genotypes GG, GH and HH for 1529A>G were detected. However, in Gulin Ma goats, the genotypes EE and HH were not found. Moreover, the base of G at position 1179 and A at position 1529 were linked (By Arlequin ver 3.1, Zoological Institute, Berne, Switzerland, http://cmpg.unibe.ch/software/arlequin3,D' = 0.7496, r(2)  = 0.4421, χ(2)  = 489.8679, p = 0.000). Among these mutations, no amino acid change was found in MTNR1A, while both of the mutations in MTNR1B gene caused amino acid changes of R222H and S339G, respectively. The structural analysis showed that the R222H mutation occurred in the first amino acid residue of the third cytoplasmic loop, and the S339G mutation was located in the carboxyl terminus of the protein. In terms of seasonal breeding, all the genotypes we detected showed a similar kidding frequency distribution trend with a higher frequency in May-August than in January-April and in September-December. This suggests that the relationship between the polymorphisms in the MTNR1A and MTNR1B genes and seasonal breeding could not be established.

Analysis of reliability metrics and quality enhancement measures in current density imaging

Low frequency current density imaging (LFCDI) is a magnetic resonance imaging (MRI) technique which enables calculation of current pathways within the medium of study. The induced current produces a magnetic flux which presents itself in phase images obtained through MRI scanning. A class of LFCDI challenges arises from the subject rotation requirement, which calls for reliability analysis metrics and specific image registration techniques. In this study these challenges are formulated and in light of proposed discussions, the reliability analysis of calculation of current pathways in a designed phantom and a pig heart is presented. The current passed is measured with less than 5% error for phantom, using CDI method. It is shown that Gauss's law for magnetism can be treated as reliability metric in matching the images in two orientations. For the phantom and pig heart the usefulness of image registration for mitigation of rotation errors is demonstrated. The reliability metric provides a good representation of the degree of correspondence between images in two orientations for phantom and pig heart. In our CDI experiments this metric produced values of 95% and 26%, for phantom, and 88% and 75% for pig heart, for mismatch rotations of 0 and 20 degrees respectively.

Cisplatin induces serotonin release from human peripheral blood mononuclear cells of cancer patients and methylprednisolone inhibits this effect

The aim of this study was to verify whether cisplatin (CDDP) can induce serotonin (5HT) release from peripheral blood mononuclear cells (PBMC) of cancer patients and determine whether methylprednisolone (MP) can inhibit such release. Ten patients (mean age 61.8 years) with cancer of different sites, all but one in advanced stage of disease were studied. Our study showed that unstimulated PBMC of cancer patients release a higher amount of 5HT than that of healthy subjects (57+/-5 nM vs 10+/-1 nM, p<0.001) and that similarly the stimulation with PHA or CDDP induces a higher amount of 5HT release by PBMC of cancer patients than that by PBMC of healthy subjects (74+/-6 vs 32+/-3 nM, p<0.001 and 91+/-8 vs 18+/-2 nM, p<0.001, respectively). The addition of MP to the culture in the presence of CDDP induced a significant decrease of 5HT levels: from 91+/-8 to 53+/-7 nM, p=0.002. This result obtained in cancer patients paralleled that previously obtained by us in healthy subjects. Our data confirm a new mechanism through which CDDP could induce emesis and provide a further possible explanation to the anti-emetic activity of corticosteroids, such as MP.

Mutations of p53 gene in hepatocellular-carcinoma (hcc) correlate with tumor progression and patient prognosis - a study of 138 patients with unifocal hcc

The mutation spectrum of p53 gene and its biological significance were studied in 138 patients with unifocal primary hepatocellular carcinoma (HCC) in Taiwan. The p53 mutations were detected in 51 cases (37%); 36 (71%) were missense mutations. The others (29%) included mutations at the intron-exon junctions (5 cases), deletion or insertion (4 cases), nonsense mutations (4 cases), and silent mutations (2 cases). The mutation sites were scattered from exons 4 to 10, predominantly (75%) in exons 5, 7, and 8. Of these mutations, 72% were transversions, mostly G:C --> T:A change (46%); while only 28% were transitions. Mutation occurred at codon 249 only in 14 cases (10%), but accounted for 27% of the mutations. The p53 mutations correlated with allele loss of p53 locus (52% vs 17% p<0.02), alpha-fetoprotein elevation (45% vs 28%, p<0.04), and poorly differentiated HCC (46% vs 10%, p<0.0001). The p53 mutation rate was two times higher in large than in small HCC (48% vs 26%, p<0.008), and in more advanced tumor (stage 3 vs stages 1 and 2: 49% vs 21%, p<0.0007). HCC patients with mutated p53 gene had a worse outcome (5-year survival; 18% vs 38%, p<0.008). We conclude that p53 gene mutation is common in advanced HCC, occurs as a late event in HCC growth, correlates with tumor progression and aggression, and is a useful molecular prognostic parameter of HCC. The p53 mutation patterns did not correlate with HBV or HCV infection. The frequency of p53 mutations did not differ between Taiwanese patients and mainland Chinese in Taiwan. However, mutation at codon 249 was more common in Taiwanese patients (p<0.05), while mutations of other types more frequent in the mainlanders (p<0.03). Hence endogenous and exogenous factors other than aflatoxin may also play a role in p53 mutation in HCC.

PRACTICAL PARALLEL IMAGING COMPRESSED SENSING MRI: SUMMARY OF TWO YEARS OF EXPERIENCE IN ACCELERATING BODY MRI OF PEDIATRIC PATIENTS

For the last two years, we have been experimenting with applying compressed sensing parallel imaging for body imaging of pediatric patients. It is a joint-effort by teams from UC Berkeley, Stanford University and GE Healthcare. This paper aims to summarize our experience so far. We describe our acquisition approach: 3D spoiled-gradient-echo with poisson-disc random undersampling of the phase encodes. Our re-construction approach: ℓ₁-SPIRiT, an iterative autocalibrating parallel imaging reconstruction that enforces both data consistency and joint-sparsity in the wavelet domain. Our implementation: an on-line parallelized implementation of ℓ₁-SPIRiT on multi-core CPU and General Purpose Graphics Processors (GPGPU) that achieves sub-minute 3D reconstructions with 8-channels. Clinical results showing higher quality reconstruction and better diagnostic confidence than parallel imaging alone at accelerations on the order of number of coils.

A systematic review of interventions by healthcare professionals on community-dwelling postmenopausal women with osteoporosis

A systematic review was conducted to evaluate evidence concerning the effect of non-drug interventions by healthcare professionals on community-dwelling postmenopausal osteoporotic women. Evidence available indicates that such interventions are effective in improving the quality of life, medication compliance, and calcium intake, but effect on other outcomes is less conclusive.

INTRODUCTION

The purpose of this study is to conduct a systematic review to evaluate evidence concerning the effect of non-drug interventions by healthcare professionals on community-dwelling postmenopausal osteoporotic women.

METHODS

Randomized controlled trials (RCTs) published in English between year 1990 and 2009 were identified. Types of patient outcome used as assessment included quality of life (QOL), bone mineral density (BMD), medication compliance and persistence, knowledge level, and lifestyle modification.

RESULTS

Twenty four RCTs met the inclusion criteria. Seven studies assessed interventions by physiotherapists, six by physicians, seven by nurses, three by multi-disciplinary teams and one by dietitians. Variability in the types and intensity of interventions made comparison between each study difficult. Collectively, these studies provided some evidence to show that interventions by healthcare professionals improved the QOL medication compliance and calcium intake of patients but its effects on BMD, medication persistence, knowledge, and other lifestyle modifications were less conclusive.

CONCLUSIONS

From this review, it was found that some outcome measures of such non-drug interventions still required further studies. Future studies should use validated instruments to assess the outcomes, with focus on common definitions of interventions and outcome measures, more intensive one-to-one interventions, appropriate control groups, adequate randomization procedures, and also provide information on effect size.

Utility of virosomal adjuvated influenza vaccines: a review of the literature

In spite of the efforts of the World Health Organization (WHO), influenza continues to be a major public health problem, both because of its impact on the health of subjects at risk, such as the elderly, and because of the economic burden that it places on society. Adjuvants are agents which, when incorporated into vaccines, enhance the immunogenicity of their antigens. The need for ever more immunogenic and efficacious influenza vaccines has led to the development of innovative vaccines. One of these, the virosomal vaccine, has been on the market since 1997. The results obtained through controlled clinical studies and widespread application in the field suggest that the virosomal vaccine is not only an important tool for the prevention of seasonal influenza but also a valid means of potentiating the effect of a pandemic influenza vaccine and, perhaps, of preparing multivalent or combined vaccines.

Wavelet-based prognostic model with comparative genomic hybridization (CGH) data in patients with hepatocellular carcinoma (HCC)

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Background: In order to obtain a good prognostic model for HCC, clinical data alone may not be adequate. DNA microarray technology has enabled quantification of thousands of genes in a single assay but it has the inborn drawback of high background noise. In order to deal with the problem of information overflow, we developed multivariate dependencies approach using CGH to guide the initial modeling process. This approach takes into account the multivariate nature and potential interaction among the genes during the prognostic modeling process. Methods: The study includes 165 patients with CGH data containing 858 regions/bands. The clinical outcome is survival at 1.72 years. Potential prognostic factors include CGH regions, albumin, ALT, bilirubin, AFP, ascites, alkaline phosphatase (ALP), tumor size, and encephalopathy. We used a blocked wavelet-shrinkage principal component analysis (BWSPCA) to reduce the dimension of CGH data with respect to clinical outcome and followed by logistic regression. We compared the BWSPCA with PCA alone, supervised PCA (Bair et al. 2004), and supervised BWSPCA. Results: Among the 165 patients, 133 (80%) were male, average age of 54.8 years, 78 (47%) stage I-II and 75 (45%) ECOG 0–2. PCA alone and supervised PCA models failed to identify significant CGH regions. BWSPCA model includes tumor size (p = 0.005), albumin (p = 0.047), ALP (p = 0.025), Chr.6q25.1 (p = 0.031), Chr.12q24.32 (p = 0.012), Chr.Xq28 (p = 0.035). Supervised BWSPCA approach includes tumor size (p = 0.016), ALP (p = 0.002), Chr.12q24.11 (p = 0.047). The area under the receiver operating curve (ROC) for the BWSPCA model was 0.78 with a sensitivity and specificity about 0.8 and 0.6 respectively. Conclusions: PCA alone is not effective in identifying CGH regions as prognostic factors. Supervised learning approach did not improve the results. The BWSPCA method identified a number of significant CGH regions associated with survival outcome for HCC patients. These results would be verified in future study. This method will be extended and applied to develop prognostic models using both CGH and DNA microarray data. Acknowledgement: This study is funded by the Research Grant Council of Hong Kong #CUHK4469/03M.

No significant financial relationships to disclose.

Temporal trends in small cell lung cancer: Analysis of the national Surveillance, Epidemiology, and End-Results (SEER) database

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Background: Research interest in small cell lung cancer (SCLC) has waned over the past 10 years due to the lack of significant therapeutic advances and a presumed decline in the incidence of SCLC. Methods: We analyzed data on all patients with primary bronchogenic carcinoma registered in the national SEER database from 1973–2002. To identify temporal trends, the study period was divided into three decades: 1973–1982 (D1), 1983–1992 (D2), and 1993–2002 (D3). Results: Of 318,584 eligible patients, 59,704 (18.7%) had SCLC. The proportional incidence of SCLC relative to non-SCLC was higher in Caucasians than African-Americans (19.6% vs 13.9%), women vs men (21% vs 17.4%), and patients ≥ 50 yrs old vs < 50 yrs old (18.9% vs 16%). By decade, the proportional incidence of SCLC was: D1, 18.4%; D2, 19.8%; D3, 17.9%. The overall incidence rates for both SCLC and non-SCLC initially rose and then declined during the study period. The incidence rates for SCLC were similar in both Caucasians and African-Americans throughout the study period, while those for non-SCLC were significantly higher in African-Americans. The gap between incidence rates in men and women has narrowed to a similar degree for both SCLC (M/F: D1, 2.6/1 to D3 1.4/1) and NSCLC (M/F: D1, 3.3/1 to D3, 1.7/1). Only 0.8% of SCLC patients underwent surgical resection from 1988–2002. The use of radiotherapy decreased during the study period (D1, 53% to D3, 43%) with greater use in younger patients and African-Americans. Stage-specific 2- and 5-year survival rates for SCLC improved over time (regional 2-yr/5-yr: D1, 15%/6.8% to D3, 22%/11%; distant 2-yr/5-yr: D1, 3.4%/1.3% to D3, 5.6%/1.9%). In multivariate analysis, significant favorable prognostic factors included: younger age, Caucasian race, female gender, limited stage, and later year of diagnosis. Conclusions: The proportional incidence of SCLC has declined only slightly over the past three decades. While overall survival has modestly improved, SCLC remains a major public health problem.

No significant financial relationships to disclose.