Effect of next-step antidepressant treatment on suicidal ideation: findings from the VAST-D trial

BACKGROUND

Major depressive disorder (MDD) contributes to suicide risk. Treating MDD effectively is considered a key suicide prevention intervention. Yet many patients with MDD do not respond to their initial medication and require a 'next-step'. The relationship between next-step treatments and suicidal thoughts and behaviors is uncharted.

METHOD

The VA Augmentation and Switching Treatments for Depression trial randomized 1522 participants to one of three next-step treatments: Switching to Bupropion, combining with Bupropion, and augmenting with Aripiprazole. In this secondary analysis, features associated with lifetime suicidal ideation (SI) and attempts (SA) at baseline and current SI during treatment were explored.

RESULTS

Compared to those with SI only, those with lifetime SI + SA were more likely to be female, divorced, or separated, unemployed; and to have experienced more childhood adversity. They had a more severe depressive episode and were more likely to respond to 'next-step' treatment. The prevalence of SI decreased from 46.5% (694/1492) at baseline to 21.1% (315/1492) at end-of-treatment. SI during treatment was associated with baseline SI; low positive mental health, more anxiety, greater severity and longer duration of current MDD episode; being male and White; and treatment with S-BUP or C-BUP as compared to A-ARI.

CONCLUSION

SI declines for most patients during next-step medication treatments. But about 1 in 5 experienced emergent or worsening SI during treatment, so vigilance for suicide risk through the entire 12-week acute treatment period is necessary. Treatment selection may affect the risk of SI.

Paeonol Derivative, 6'-Methyl Paeonol, Attenuates Aβ-Induced Pathophysiology in Cortical Neurons and in an Alzheimer's Disease Mice Model

Herbs themselves and various herbal medicines are great resources for discovering therapeutic drugs for various diseases, including Alzheimer's disease (AD), one of the common neurodegenerative diseases. Utilizing mouse primary cortical neurons and DiBAC4(3), a voltage-sensitive indicator, we have set up a drug screening system and identified an herbal extraction compound, paeonol, obtained from Paeonia lactiflora; this compound is able to ameliorate the abnormal depolarization induced by Aβ42 oligomers. Our aim was to further find effective paeonol derivatives since paeonol has been previously studied. 6'-Methyl paeonol, one of the six paeonol derivatives surveyed, is able to inhibit the abnormal depolarization induced by Aβ oligomers. Furthermore, 6'-methyl paeonol is able to alleviate the NMDA- and AMPA-induced depolarization. When a molecular mechanism was investigated, 6'-methyl paeonol was found to reverse the Aβ-induced increase in ERK phosphorylation. At the animal level, mice injected with 6'-methyl paeonol showed little change in their basic physical parameters compared to the control mice. 6'-Methyl paeonol was able to ameliorate the impairment of memory and learning behavior in J20 mice, an AD mouse model, as measured by the Morris water maze. Thus, paeonol derivatives could provide a structural foundation for developing and designing an effective compound with promising clinical benefits.

Targeted Molecular Profiling of Circulating Cell-Free DNA in Patients With Advanced Hepatocellular Carcinoma

PURPOSE

Next-generation sequencing (NGS) of tumor-derived, circulating cell-free DNA (cfDNA) may aid in diagnosis, prognostication, and treatment of patients with hepatocellular carcinoma (HCC). The operating characteristics of cfDNA mutational profiling must be determined before routine clinical implementation.

METHODS

This was a single-center, retrospective study with the primary objective of defining genomic alterations in circulating cfDNA along with plasma-tissue genotype agreement between NGS of matched tumor samples in patients with advanced HCC. cfDNA was analyzed using a clinically validated 129-gene NGS assay; matched tissue-based NGS was analyzed with a US Food and Drug Administration-authorized NGS tumor assay.

RESULTS

Fifty-three plasma samples from 51 patients with histologically confirmed HCC underwent NGS-based cfDNA analysis. Genomic alterations were detected in 92.2% of patients, with the most commonly mutated genes including TERT promoter (57%), TP53 (47%), CTNNB1 (37%), ARID1A (18%), and TSC2 (14%). In total, 37 (73%) patients underwent paired tumor NGS, and concordance was high for mutations observed in patient-matched plasma samples: TERT (83%), TP53 (94%), CTNNB1 (92%), ARID1A (100%), and TSC2 (71%). In 10 (27%) of 37 tumor-plasma samples, alterations were detected by cfDNA analysis that were not detected in the patient-matched tumors. Potentially actionable mutations were identified in 37% of all cases including oncogenic/likely oncogenic alterations in TSC1/2 (18%), BRCA1/2 (8%), and PIK3CA (8%). Higher average variant allele fraction was associated with elevated alpha-fetoprotein, increased tumor volume, and no previous systemic therapy, but did not correlate with overall survival in treatment-naïve patients.

CONCLUSION

Tumor mutation profiling of cfDNA in HCC represents an alternative to tissue-based genomic profiling, given the high degree of tumor-plasma NGS concordance; however, genotyping of both blood and tumor may be required to detect all clinically actionable genomic alterations.

Murine cytotoxic CD4+ T cells in the tumor microenvironment are at a hyper-maturation stage of Th1 CD4+ T cells sustained by IL-12

The roles of tumor-infiltrating CD4+Foxp3- T cells are not well characterized due to their plasticity of differentiation, and varying levels of activation or exhaustion. To further clarify this issue, we used a model featuring subcutaneous murine colon cancer and analyzed the dynamic changes of phenotype and function of the tumor-associated CD4+ T-cell response. We found that, even at a late stage of tumor growth, the tumor-infiltrating CD4+Foxp3- T cells still expressed effector molecules, inflammatory cytokines and molecules that are expressed at reduced levels in exhausted cells. We used microarrays to examine the gene-expression profiles of different subsets of CD4+ T cells and revealed that the tumor-infiltrating CD4+Foxp3- T cells expressed not only type 1 helper (Th1) cytokines, but also cytolytic granules such as those encoded by Gzmb and Prf1. In contrast to CD4+ regulatory T cells, these cells exclusively co-expressed natural killer receptor markers and cytolytic molecules as shown by flow-cytometry studies. We used an ex vivo killing assay and proved that they could directly suppress CT26 tumor cells through granzyme B and perforin. Finally, we used pathway analysis and ex vivo stimulation to confirm that the CD4+Foxp3- T cells expressed higher levels of IL12rb1 genes and were activated by the IL-12/IL-27 pathway. In conclusion, this work finds that, in late-stage tumors, the tumor-infiltrating lymphocyte population of CD4+ cells harbored a sustained, hyper-maturated Th1 status with cytotoxic function supported by IL-12.

Cost-effective methylome sequencing of cell-free DNA for accurately detecting and locating cancer

Early cancer detection by cell-free DNA faces multiple challenges: low fraction of tumor cell-free DNA, molecular heterogeneity of cancer, and sample sizes that are not sufficient to reflect diverse patient populations. Here, we develop a cancer detection approach to address these challenges. It consists of an assay, cfMethyl-Seq, for cost-effective sequencing of the cell-free DNA methylome (with > 12-fold enrichment over whole genome bisulfite sequencing in CpG islands), and a computational method to extract methylation information and diagnose patients. Applying our approach to 408 colon, liver, lung, and stomach cancer patients and controls, at 97.9% specificity we achieve 80.7% and 74.5% sensitivity in detecting all-stage and early-stage cancer, and 89.1% and 85.0% accuracy for locating tissue-of-origin of all-stage and early-stage cancer, respectively. Our approach cost-effectively retains methylome profiles of cancer abnormalities, allowing us to learn new features and expand to other cancer types as training cohorts grow.

Next-generation sequencing (NGS) of circulating cell-free DNA (cfDNA) in patients (pts) with advanced hepatocellular carcinoma (HCC)

4110

Background: HCC is often diagnosed based on high-quality cross-sectional imaging, and when a biopsy is pursued, acquisition of tissue may be of limited quantity and quality or complicated by underlying medical comorbidities. NGS of tumor derived circulating cfDNA represents an investigational tool for non-invasive molecular profiling, that has the potential to aid in diagnosis, prognosis, and in monitoring disease status. Although prior reports have evaluated such technologies, few studies have included tumor tissues to confirm histology and to explore plasma-tissue gene concordance. Methods: The primary objective of this retrospective cohort study was to define genomic alterations in circulating cfDNA and to explore plasma-tissue genotype concordance in HCC pts. HCC pts underwent collection of cfDNA for NGS using the MSK-ACCESS 129-gene assay between August 2019 and February 2021. Matched tissue-based NGS with the FDA authorized MSK-IMPACT gene assay was completed when tumor tissue was available. Clinical actionability of sequence variants was annotated by OncoKB, an FDA recognized knowledge base. Clinicopathologic characteristics were extracted, and all data were reported with descriptive statistics. Results: 51 unique patients with 53 plasma samples had an HCC histological diagnosis. Pts were male (39, 76%), median age 69 (42-87), viral hepatitis-related (24, 47%), and advanced stage (Stage III:9, 18%; Stage IV:38, 74.5%). Extrahepatic disease and macrovascular involvement were observed in 28 (55%) and 19 (38%) pts, respectively. 22 (43%) pts had AFP ≥400 ng/mL. 49 (92.5%) of 53 plasma samples had detectable genomic alterations. Median cfDNA yield after extraction was 39.43 ng (range: 7.93-287.68). The most frequently mutated genes occurring in > 10% of patients were TERT (57%), TP53 (47%), CTNNB1 (37%), ARID1A (18%) and TSC2 (14%). The most common oncogenic pathways that contained alterations were WNT-β-Catenin (45%) and PIK3-AKT-TOR (25%). 37 (73%) pts underwent tissue sequencing with MSK-IMPACT with a median time of 9.0 months to the time cfDNA testing. MSK-ACCESS identified mutations observed in tumor in most cases: TERT (20/22; 91%), TP53 (16/17; 94%), CTNNB1 (11/12; 92%), ARID1A (6/6; 100%) and TSC2 (6/7; 86%). In 18 (49%) of 37 paired samples, additional mutations in cfDNA not seen in tumor were detected and included KRAS, EGFR, and TP53 alterations. Potentially actionable mutations were identified through cfDNA in 37% of cases including TSC1/2 (18%), BRCA1/ 2 (8%) and PIK3CA (8%). Conclusions: Circulating cfDNA genotyping with MSK-ACCESS identifies previously reported HCC tumor genomic profiles and revealed tumor-associated mutations in 92.5% of plasma samples. Ongoing efforts will explore predictive and prognostic implications of NGS at different HCC stages as well as kinetics of treatment response.

Circulating Tumor Cell-Based Messenger RNA Scoring System for Prognostication of Hepatocellular Carcinoma: Translating Tissue-Based Messenger RNA Profiling Into a Noninvasive Setting

Numerous studies in hepatocellular carcinoma (HCC) have proposed tissue-based gene signatures for individualized prognostic assessments. Here, we develop a novel circulating tumor cell (CTC)-based transcriptomic profiling assay to translate tissue-based messenger RNA (mRNA) signatures into a liquid biopsy setting for noninvasive HCC prognostication. The HCC-CTC mRNA scoring system combines the NanoVelcro CTC Assay for enriching HCC CTCs and the NanoString nCounter platform for quantifying the HCC-CTC Risk Score (RS) panel in enriched HCC CTCs. The prognostic role of the HCC-CTC RS was assessed in The Cancer Genome Atlas (TCGA) HCC cohort (n = 362) and validated in an independent clinical CTC cohort (n = 40). The HCC-CTC RS panel was developed through our integrated data analysis framework of 8 HCC tissue-based gene signatures and identified the top 10 prognostic genes (discoidin domain receptor tyrosine kinase 1 [DDR1], enoyl-CoA hydratase and 3-hydroxyacyl CoA dehydrogenase [EHHADH], androgen receptor [AR], lumican [LUM], hydroxysteroid 17-beta dehydrogenase 6[HSD17B6], prostate transmembrane protein, androgen induced 1 [PMEPA1], tsukushi, small leucine rich proteoglycan [TSKU], N-terminal EF-hand calcium binding protein 2 [NECAB2], ladinin 1 [LAD1], solute carrier family 27 member 5 [SLC27A5]) highly expressed in HCC with low expressions in white blood cells. The panel accurately discriminated overall survival in TCGA HCC cohort (hazard ratio [HR], 2.0; 95% confidence interval [CI], 1.4-2.9). The combined use of the scoring system and HCC-CTC RS panel successfully distinguished artificial blood samples spiked with an aggressive HCC cell type, SNU-387, from those spiked with PLC/PRF/5 cells (P = 0.02). In the CTC validation cohort (n = 40), HCC-CTC RS remained an independent predictor of survival (HR, 5.7; 95% CI, 1.5-21.3; P = 0.009) after controlling for Model for End-Stage Liver Disease score, Barcelona Clinic Liver Cancer stage, and CTC enumeration count. Our study demonstrates a novel interdisciplinary approach to translate tissue-based gene signatures into a liquid biopsy setting. This noninvasive approach will allow real-time disease profiling and dynamic prognostication of HCC.

Detection of Circulating Tumor Cells and Their Implications as a Biomarker for Diagnosis, Prognostication, and Therapeutic Monitoring in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is among the leading causes of worldwide cancer-related morbidity and mortality. Poor prognosis of HCC is attributed primarily to tumor presentation at an advanced stage when there is no effective treatment to achieve the long term survival of patients. Currently available tests such as alpha-fetoprotein have limited accuracy as a diagnostic or prognostic biomarker for HCC. Liver biopsy provides tissue that can reveal tumor biology but it is not used routinely due to its invasiveness and risk of tumor seeding, especially in early-stage patients. Liver biopsy is also limited in revealing comprehensive tumor biology due to intratumoral heterogeneity. There is a clear need for new biomarkers to improve HCC detection, prognostication, prediction of treatment response, and disease monitoring with treatment. Liquid biopsy could be an effective method of early detection and management of HCC. Circulating tumor cells (CTCs) are cancer cells in circulation derived from the original tumor or metastatic foci, and their measurement by liquid biopsy represents a great potential in facilitating the implementation of precision medicine in patients with HCC. CTCs can be detected by a simple peripheral blood draw and potentially show global features of tumor characteristics. Various CTC detection platforms using immunoaffinity and biophysical properties have been developed to identify and capture CTCs with high efficiency. Quantitative abundance of CTCs, as well as biological characteristics and genomic heterogeneity among the CTCs, can predict disease prognosis and response to therapy in patients with HCC. This review article will discuss the currently available technologies for CTC detection and isolation, their utility in the clinical management of HCC patients, their limitations, and future directions of research.

Hepatocellular Carcinoma-Circulating Tumor Cells Expressing PD-L1 Are Prognostic and Potentially Associated With Response to Checkpoint Inhibitors

Hepatocellular carcinoma (HCC) is a leading cause of mortality. Checkpoint inhibitors of programmed cell death protein-1 (PD-1) and programmed death-ligand 1 (PD-L1) have shown great efficacy, but lack biomarkers that predict response. Circulating tumor cells (CTCs) have promise as a liquid-biopsy biomarker; however, data on HCC CTCs expressing PD-L1 have not been reported. We sought to detect PD-L1-expressing HCC-CTCs and investigated their role as a prognostic and predictive biomarker. Using an antibody-based platform, CTCs were enumerated/phenotyped from a prospective cohort of 87 patients with HCC (49 early-stage, 22 locally advanced, and 16 metastatic), 7 patients with cirrhosis, and 8 healthy controls. Immunocytochemistry identified total HCC CTCs (4',6-diamidino-2-phenylindole-positive [DAPI+]/cytokeratin-positive [CK+]/clusters of differentiation 45-negative [CD45-]) and a subpopulation expressing PD-L1 (DAPI+/CK+/PD-L1+/CD45-). PD-L1+ CTCs were identified in 4 of 49 (8.2%) early-stage patients, but 12 of 22 (54.5%) locally advanced and 15 of 16 (93.8%) metastatic patients, accurately discriminating early from locally advanced/metastatic HCC (sensitivity = 71.1%, specificity = 91.8%, area under the receiver operating characteristic curve = 0.807; P < 0.001). Compared to patients without PD-L1+ CTCs, patients with PD-L1+ CTCs had significantly inferior overall survival (OS) (median OS = 14.0 months vs. not reached, hazard ratio [HR] = 4.0, P = 0.001). PD-L1+ CTCs remained an independent predictor of OS (HR = 3.22, P = 0.010) even after controlling for Model for End-Stage Liver Disease score (HR = 1.14, P < 0.001), alpha-fetoprotein (HR = 1.55, P < 0.001), and overall stage/tumor burden (beyond University of California, San Francisco, HR = 7.19, P < 0.001). In the subset of 10 patients with HCC receiving PD-1 blockade, all 5 responders demonstrated PD-L1+ CTCs at baseline, compared with only 1 of 5 nonresponders, all of whom progressed within 4 months of starting treatment. Conclusion: We report a CTC assay for the phenotypic profiling of HCC CTCs expressing PD-L1. PD-L1+ CTCs are predominantly found in advanced-stage HCC, and independently prognosticate OS after controlling for Model for End-Stage Liver Disease, alpha-fetoprotein, and tumor stage. In patients with HCC receiving anti-PD-1 therapy, there was a strong association with the presence of PD-L1+ CTCs and favorable treatment response. Prospective validation in a larger cohort will better define the utility of PD-L1+ CTCs as a prognostic and predictive biomarker in HCC.

Tunable magnetic low-frequency noise in magnetic tunnel junctions: effect of shape anisotropy

The intrinsic magnetic low-frequency noise (LFN) is of fundamental scientific interest to the study of magnetic tunnel junctions (MTJs). To gain insight into its mechanism, the fluctuation-dissipation theorem, which describes the linear relation between magnetic LFN and magnetic sensitivity product, has been utilized. However, deviation from the linear correlation has been reported in some studies. To understand and effectively control the magnetic LFN, a more elaborate analytical description and further experimental validation are required. In this work, the magnetic LFN contributed from the magnetization fluctuation in the pinned layer of MTJs with various shape anisotropies was investigated. The MTJs with different shape anisotropies, achieved by altering their aspect ratios, possessed distinct demagnetizing factors. Large magnetic noise was correlated with the increase of magnetic phase loss of ferromagnetic layers during magnetization reversal at which magnetization fluctuation was enhanced. Upon increasing the shape anisotropy, a notable reduction of the magnetic phase loss in the antiparallel (AP) state was observed while it exhibited a slight decrease in the parallel (P) state, revealing that the increase of the shape anisotropy caused a more pronounced suppression of the equilibrium magnetization fluctuation in the AP state. These phenomena were computationally validated by constructing a macrospin model to describe the thermally-induced magnetization fluctuation in the pinned layer. This work reveals the physical relation between MTJ shape anisotropy and magnetic LFN. The effect of the shape anisotropy on the magnetic LFN can be extended to other types of in-plane uniaxial anisotropies.

Abstract 5436: Purification and mRNA profiling of extracellular vesicles for early detection of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the 4th most common cause of cancer-related deaths worldwide. The poor prognosis of HCC is due to the fact that diagnosis is often made at an advanced stage in disease development. It is crucial to develop a non-invasive liquid biopsy-based diagnostic solution for early detection of HCC. In this study, we developed a covalent chemistry-based nanostructured silicon substrate (“EV Click Chip”) for the isolation of HCC extracellular vesicles (EVs). The EV Click Chip leverages specific click chemistry reactions and sensitive multi-marker cocktail antibody identification of the HCC EVs. The EV Click Chip also allows for the subsequent release of the captured HCC EVs and is optimal for the downstream molecular analysis. A well-validated 10 liver-specific genes were quantified using reverse transcription droplet digital PCR (RT-ddPCR) in HCC EVs purified by the optimized EV Click Chips for the detection of HCC. Our EV Click Chip-based HCC-EV Assay is able to differentiate HCC from non-HCC controls (chronic liver diseases, healthy donors and other cancers) and outperformed clinical AFP test for distinguishing early-stage HCC from at-risk cirrhotic patients.

Citation Format: Yi-Te Lee, Na Sun, Ryan Y. Zhang, Rueihung Kao, Pin-Jung Chen, Pai-Chi Teng, Jasmine J. Wang, Yingying Yang, Minhyung Kim, Edwin M. Posadas, Sungyong You, Ju Dong Yang, Vatche G. Agopian, Hsian-Rong Tseng, Yazhen Zhu. Purification and mRNA profiling of extracellular vesicles for early detection of hepatocellular carcinoma [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 5436.

Abstract 4331: Nuclear size of circulating tumor cells is associated with prognosis in metastatic, castration-resistant prostate cancer

Background: Current risk stratification models in prostate cancer (PC) have been based on clinical and pathological variables. Beyond serum prostate-specific antigen (PSA) concentration measurements, there remain few new biomarkers to help identify patients at risk for poor clinical outcomes. Morphological analyses using Gleason scoring along with cell nuclear size and shape remains to be a fundamental pathological practice of PC that have been utilized to identify aggressive diseases and to associate with aggressive metastasis. In particular, changes in nuclear shape and composition have been associated with outcome in early stage disease. Circulating tumor cells (CTCs) have arisen as contemporary noninvasive prognostic biomarkers for PC. Previously, a subgroup of PC CTCs, with prominently small nuclei (&lt; 8.5 μm), were found to be correlated with the presence of visceral metastases. This subgroup was named very-small-nuclear CTCs (vsnCTCs). We proposed vsnCTCs as a putative biomarker of a lethal subtype in metastatic castration resistant PC (mCRPC).

Methods: In this study, 76 patients with mCRPC were recruited for overall survival (OS) analysis. Of the 76 patients, 50 had available pre-treatment blood specimens prior to the initiation of androgen receptor signaling inhibitor (ARSI, e.g. abiraterone and enzalutamide) or taxane or tyrosine kinase inhibitor therapy. Using the NanoVelcro CTC Enumeration Assay, CTCs were captured and subjected to immunofluorescence staining. CTCs were identified as DAPI+/CK+/CD45- with a round or oval nucleus. Additionally, CTC nuclear size was measured and defined as the square root of the product of the long axis and the short axis. Kaplan-Meier analysis and Cox proportional hazards model were conducted.

Results: Patients with vsnCTC (i.e., vsnCTC+) had a significantly shortened OS compared with patients without vsnCTC (i.e., vsnCTC-). The median OS was 34 (vsnCTC+, n=49) vs. 149 (vsnCTC-, n=27) weeks (log-rank HR=2.6 with 95% CI 1.5 to 4.5, p=0.0006). Progression free survival (PFS) analysis was performed for the 50 patients with pre-treatment blood samples. The median PFS was 12 (vsnCTC+, n=32) vs. 26 (vsnCTC-, n=18) weeks (log-rank HR=2.2 with 95% CI 1.3 to 4.0, p=0.0038). We also found that the hazard ratio of overall survival increased significantly as the CTC nuclear size decreased using the p-spline plot.

Conclusions: Our study showed that nuclear size reduction has importance in CTCs in a fashion similar to its utility in tissue. This study points toward the importance of the vsnCTC in patients with mCRPC, as vsnCTC+ patients represented a group at risk for faster clinical progression who are at the highest risk for morality. We posit that the vsnCTC represents a new hallmark of an aggressive subtype of mCRPC. This has potential importance in optimizing therapeutic choices.

Citation Format: JASMINE J. WANG, Pai-Chi Teng, Yu Jen Jan, Jie-Fu Chen, Galen Cook-Wiens, Nu Yao, Gina C. Chu, Pin-Jung Chen, Yingying Yang, Yee Hui Yeo, Yi-Te Lee, Leland W. Chung, Sungyong You, Yazhen Zhu, Michael R. Freeman, Andre Rogatko, Ju Dong Yang, Hsian-Rong Tseng, Edwin M. Posadas. Nuclear size of circulating tumor cells is associated with prognosis in metastatic, castration-resistant prostate cancer [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 4331.

Abstract 5447: Gene expression of circulating tumor cells is predictive of treatment response in patients with advanced prostate cancer

Background: Genome and transcriptome-based analysis has begun to reshape the approach to prostate cancer (PC). Two different gene expression signatures have shown that PC can be divided into 3 subclasses reflecting luminal-basal biology. These subtypes point toward biological drivers that may strongly influence how care should be personalized including optimization of androgen receptor targeted therapy. The majority of work done in this area has been based on tissue-based gene expression. With the advent of newer nanotechnology platforms for isolation of circulating tumor cells (CTCs), profiling of PC gene expression from blood is now possible.

Methods: We recruited 34 patients with metastatic castration resistant PC who had available blood specimens prior to initiation of androgen receptor signaling inhibitor (ARSI, e.g. abiraterone, enzalutamide and apalutamide) therapy. We combined variations of the NanoVelcro Assays (thermoresponsive, click-chemistry) allowing for capture and release of CTCs with intact mRNA. Gene sets from the PCS and PAM50 signatures were re-reviewed to optimize signal detection in the blood and enriched for genes upregulated in PC. The NanoString nCounter platform was applied to profile the resulting genes. A pilot study was conducted using banked samples available through the Urologic Oncology Program Blood and Biospecimen Bank at Cedars-Sinai Medical Center.

Results: The final assay was tested in banked blood samples and provided classifications of patients that associated with clinical responsiveness to therapy. Validation was conducted to examine the performance of the CTC-specific PCS/PAM50 panel in public databases (including Prostate Cancer Transcriptome Atlas and GenomeDx). Our pilot study showed that the median overall survival was significantly worse in PCS1 patients.

Conclusions: This study shows initial proof of principle that genomic classification in blood is possible using contemporary tool for blood component isolation and RNA profiling. Additional technical and clinical validations are needed prior to widespread implementation, but these methods may make it possible to increase the utilization of genomic classifiers in clinical studies and in practice.

Citation Format: PAI-CHI TENG, Minhyung Kim, Yu Jen Jan, Jie-Fu Chen, Nu Yao, Gina C. Chu, Pin-Jung Chen, Jasmine J. Wang, Yi-Te Lee, Yazhen Zhu, Leland W. Chung, Felix Y. Feng, Michael R. Freeman, Sungyong You, Hsian-Rong Tseng, Edwin M. Posadas. Gene expression of circulating tumor cells is predictive of treatment response in patients with advanced prostate cancer [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 5447.

Somatic copy number profiling from hepatocellular carcinoma circulating tumor cells

Somatic copy number alterations (SCNAs) are important genetic drivers of many cancers. We investigated the feasibility of obtaining SCNA profiles from circulating tumor cells (CTCs) as a molecular liquid biopsy for hepatocellular carcinoma (HCC). CTCs from ten HCC patients underwent SCNA profiling. The Cancer Genome Atlas (TCGA) SCNA data were used to develop a cancer origin classification model, which was then evaluated for classifying 44 CTCs from multiple cancer types. Sequencing of 18 CTC samples (median: 4 CTCs/sample) from 10 HCC patients using a low-resolution whole-genome sequencing strategy (median: 0.88 million reads/sample) revealed frequent SCNAs in previously reported HCC regions such as 8q amplifications and 17p deletions. SCNA profiling revealed that CTCs share a median of 80% concordance with the primary tumor. CTCs had SCNAs not seen in the primary tumor, some with prognostic implications. Using a SCNA profiling model, the tissue of origin was correctly identified for 32/44 (73%) CTCs from 12/16 (75%) patients with different cancer types.

Development of a circulating tumor cell-based RNA classifier for patients with castration-resistant prostate cancer: CTC-PCS/PAM50

e17509

Background: Genomic profiling has strongly impacted the contemporary understanding of prostate cancer (PCa). Clinical trials are now testing the utility of genomic classifiers such as the PCS (You, Ca Res 2016) and PAM50 (Zhao, JAMA Onc 2017) systems to optimize therapy selection. As contemporary tissue is not always readily available, especially in metastatic, castration-resistant PCa (mCRPC), a blood-based test would be better suited for assessing patients and predicting treatment response. Methods: The CTC-RNA assay combines the Thermoresponsive (TR)-NanoVelcro system with the NanoString nCounter platform. This allows for CTC purification and RNA analysis. Using a novel bioinformatics approach that accounts for differences in background signals between tissue and blood, we reconstructed the PCS and PAM50 panels to recapitulate both classifiers in this blood-based assay. A weighted Z-score and nearest centroid classifier were used to calculate gene expression and to assign PCS and PAM50 subtypes. Performance of the revised signatures and CTC-RNA assay was benchmarked on simulated spiked-blood specimens. An initial clinical test was performed using clinically annotated, banked blood specimens within the Translational Oncology Program Blood and Biospecimen Bank. Results: CTC-RNA profiles of C4-2B AR signaling inhibitor (ARSI)-resistant sublines were compared to parental C4-2B. C4-2B ARSI-resistant cells had significantly higher PCS1 Z scores, PCS1 probability, and basal probability compared to the parental C4-2B cells. Blood samples from 34 mCRPC patients prior to initiation of therapy with ARSIs (abiraterone, enzalutamide, or apalutamide) were then analyzed. Samples were classified as PCS1 (n = 3), PCS2 (n = 20), and PCS3 (n = 11); luminal A (n = 12), luminal B (n = 11), and basal (n = 11). The biochemical progression-free survival (bPFS) on ARSI and overall survival (OS) for PCS1/Basal vs. other are shown in the table. Conclusions: The CTC-RNA assay is capable of generating luminal-basal classifications such as those in the PCS and PAM50 systems. Given early data of these classifiers and their potential to guide therapeutic decisions, this approach may be useful as an alternative to biopsy to facilitate such decisions. Larger prospective studies will be needed to confirm and validate its clinical utility. [Table: see text]

Circulating tumor cells with small nuclear size: A novel biomarker for survival and clinical outcomes in advanced prostate cancer

e17512

Background: Very-small-nuclear circulating tumor cells (vsnCTCs) as a subset of CTCs with nuclear size < 8.5 μm associated with visceral metastases (VM) in advanced metastatic, castration-resistant prostate cancer (mCRPC). As VM predicts foreshortened survival, we hypothesized that vsnCTCs would be directly associated with poor overall survival (OS). Methods: Clinically annotated, blood samples from patients with mCRPC with survival follow-up within the Translational Oncology Program Blood & Biospecimen Bank were selected for analysis. CTCs were isolated and analyzed using the NanoVelcro assay. The nuclear size from all CTCs from each patient sample was compared to OS and progression-free survival (PFS) from the time of the blood draw. Results: A total of 76 patients had samples suitable for analysis. Sixty-six (87%) had CTCs; 49 (64%) were vsnCTC+ (≥1 vsnCTC). vsnCTCs were more common in mCRPC patients with previous androgen receptor signaling inhibitor (ARSI) therapy and/or 2 or more lines of treatment. OS was significantly shorter for vsnCTC+ than vsnCTC- patients (median 34 vs. 149 weeks; log-rank HR = 2.6; 95% CI = 1.5 to 4.5; P = 0.0006). Fifty patient samples were available for PFS analysis (i.e. drawn within 4 weeks of starting therapy). vsnCTC+ patients experienced more rapid progression than vsnCTC- patients (median 12 vs. 26 weeks, log-rank HR = 2.2, 95% CI = 1.3 to 4.0; P = 0.004). Multivariable Cox regression revealed that vsnCTC status was independently associated with OS and PFS. P-spline plot analysis showed that the HR of OS increased as the minimum CTC nuclear size decreased. The minimum CTC nuclear size was also independently associated with OS and PFS in a multivariable Cox regression analysis. Patients with prior use of androgen receptor signaling inhibitor (ARSI) therapy had significantly smaller minimum CTC nuclear size compared to those without prior use of ARSI. Average and median nuclear size did not strongly associate with OS or PFS. Conclusions: vsnCTC+ patients are at risk for more rapid clinical progression and have greater risk of death than vsnCTC-. We posit that the vsnCTC may be a biomarker of aggressive mCRPC with foreshortened survival. Interestingly, the CTCs with the smallest nuclei appear to best reflect the observed clinical behavior. This has potential importance in optimizing therapeutic choices and may point toward a unique biology relating nuclear size to aggressive molecular features. Our group continues to explore the biology underlying the vsnCTC.

[Total neoadjuvant therapy followed by watch and wait approach or organ preservation for MRI stratified low-risk rectal cancer: early result from a prospective, single arm trial]

Objective: To explore the safety and efficacy of watch and wait strategy and organ preservation surgery after total neoadjuvant treatment for MRI stratified low-risk rectal cancer. Methods: A prospective single arm phase Ⅱ trial developed at Department of Gastrointestinal Cancer, Peking University Cancer Hospital & Institute was preliminarily analyzed. Subjects were enrolled from August 2016 to January 2019. Low-risk rectal cancer with following MRI features were recruited: mid-low tumor, mrT2-3b, MRF (-), EMVI (-), CRM (-), differentiation grade 1-3. Patients received intensity-modulated radiotherapy (IMRT) 50.6 Gy/22f with concurrent capecitabine and 4 cycles of consolidation CAPEOX. Patients with cCR/near-cCR confirmed by physical examination, rectal MRI, endoscopy, and serum CEA were recommended for watch & wait approach or local excision (LE). The main study outcomes were 2-year organ preservation rate (OPR) and sphincter preservation rate (SPR). Results: Thirty-eight patients were eligible for analysis, including 24 males and 14 females with median age of 56 years; 9 cases of mrT2 (23.7%), 14 cases of mrT3a (36.8%) and 15 cases of mrT3b (39.5%); 5 cases of well differentiated adenocarcinoma (13.2%), 32 cases of moderately differentiated adenocarcinoma (84.2%) and 1 case of mucinous adenocarcinoma (2.6%). Carcinoemobryonic antigen (CEA) was elevated before treatment in 1 case. One case (2.6%) of grade 3 radiation dermatitis occurred during IMRT; 18 cases (47.4%) occurred grade 3 to 4 adverse events during consolidation chemotherapy. After total neoadjuvant treatment, the cCR and near-cCR rates were 42.1% (16/38) and 23.7% (9/38), respectively, while non-cCR rate was 34.2% (13/38). Twenty patients (20/38, 52.6%) of cCR or near-cCR underwent watch & wait approach, with a local regrowth rate of 20% (4/20). Four patients received LE, including one salvage LE. Thirteen patients (4 were ypCR) received radical resection, including 10 cases of initial low anterior resections (LAR), 1 cases of initial abdominal perineal resection (APR) and 2 cases of salvage LAR, four patients refused operation. The median follow-up time was 23.5 (8.5-38.3) months. At the last interview of follow-up, the OPR and SPR were 52.6% (20/38) and 84.2% (32/38), respectively. Only one patient developed lung metastasis and no local recurrence occurred after radical resection or LE. Conclusion: Total neoadjuvant treatment for low-risk rectal cancer achieves high cCR/near-cCR rate, with increased probability of receiving watch and wait approach and organ preservation in this subgroup.

Prostate cancer CTC-RNA Assay: A new method for contemporary genomics and precision medicine via liquid biopsy

170

Background: Transcriptome-based analysis has begun to reshape the approach to prostate cancer (PC). Two different gene expression signatures have shown that PC can be divided into 3 subclasses reflecting luminal-basal biology. These subtypes point toward biological drivers that may strongly influence how care should be personalized including optimization of androgen receptor targeted therapy. The majority of work done in this area has been based on tissue-based gene expression. With the advent of newer nanotechnology platforms for isolation of circulating tumor cells (CTCs), profiling of PC gene expression from blood is now possible. Methods: We recruited 34 patients with metastatic castration resistant PC at Cedars-Sinai Medical Center who had available blood specimens prior to initiation of androgen receptor signaling inhibitor (ARSI, e.g. abiraterone, enzalutamide and apalutamide) therapy.We utilized the NanoVelcro Assays which allow for capture and release of CTCs with intact mRNA. Gene sets from the PCS and PAM50 signatures were re-reviewed to optimize signal detection in the blood and enriched for genes upregulated in PC. The NanoString nCounter platform was used for RNA profiling. Results: The final assay was tested in banked blood samples and provided classifications of patients that associated with clinical responsiveness to therapy. Validation was conducted to examine the performance of the CTC-specific PCS/PAM50 panel in public databases (including Prostate Cancer Transcriptome Atlas and GenomeDx). Our pilot study showed that the median overall survival was significantly worse in PCS1 patients. Conclusions: This study shows initial proof of principle that genomic classification in blood is possible using contemporary tool for blood component isolation and RNA profiling. Additional technical and clinical validations are needed prior to widespread implementation, but these methods may make it possible to increase the utilization of genomic classifiers in clinical studies and in practice.

Association of very small nuclear circulating tumor cell (vsnCTC) with clinical outcomes in metastatic castration-resistant prostate cancer

168

Background: Circulating tumor cells (CTCs) have arisen as contemporary noninvasive prognostic biomarkers for prostate cancer (PC). Previously, a subgroup of PC CTCs, with particularly small nuclei (<8.5 μm), were found to be correlated with the presence of visceral metastases. This subgroup was named very-small-nuclear CTCs (vsnCTCs). We proposed vsnCTCs as a putative biomarker of a lethal subtype in metastatic castration resistant PC (mCRPC). Methods: In this study, 76 patients with mCRPC were recruited for overall survival (OS) analysis. Of the 76 patients, 47 had available pre-treatment blood specimens prior to the initiation of androgen receptor signaling inhibitor (ARSI, e.g. abiraterone and enzalutamide) or taxane therapy. Using the NanoVelcro CTC Assay, CTCs were captured and subjected to immunofluorescence staining. CTCs were identified as DAPI+/CK+/CD45- with a round or oval nucleus. Additionally, CTC nuclear size was measured and defined as the square root of the product of the long axis and the short axis. Kaplan-Meier analysis and Cox proportional hazards model were conducted. Results: Patients with vsnCTC (i.e., vsnCTC+) had a significantly shortened OS compared with patients without vsnCTC (i.e., vsnCTC-). The median OS was 34 (vsnCTC+, n=49) vs. 149 (vsnCTC-, n=27) weeks (log-rank HR=2.6 with 95% CI 1.5 to 4.5, p=0.0006). Progression free survival (PFS) analysis was performed for the 47 patients with pre-treatment blood samples. The median PFS was 14 (vsnCTC+, n=29) vs. 26 (vsnCTC-, n=18) weeks (log-rank HR=2.2 with 95% CI 1.2 to 3.9, p=0.0069). We also found that the hazard ratio of overall survival increased significantly as the CTC nuclear size decreased using the p spline plot. Conclusions: Our study showed that nuclear size reduction has importance in CTCs in a fashion similar to its utility in tissue. This study points toward the importance of the vsnCTC in patients with mCRPC, as vsnCTC+ patients represented a group at risk for faster clinical progression who are at the highest risk for morality. We posit that the vsnCTC represents a new hallmark of an aggressive subtype of mCRPC. This has potential importance in optimizing therapeutic choices.

[Short-term outcomes and prognosis of palliative surgery for malignant bowel obstruction caused by peritoneal metastasis of colorectal cancer]

Objective: To explore the short-term efficacy and prognosis of palliative surgical treatment for malignant bowel obstruction (MBO) caused by peritoneal metastasis of colorectal cancer (mCRC). Methods: A retrospective cohort study was conducted. The inclusion criteria for patients were as follows: (1) primary colorectal cancer; (2) massive peritoneal metastasis; (3)obstructive site located below Treitz ligament by imaging; (4) obstruction refractory to conservative treatment; (5) estimated rese survival time more than 2 months; (6) patients and their families had strong willingness for operation; (7) surgical treatment included stoma/bypass and debulking surgery. In accordance with the above criteria, clinicopathological data of 46 patients undergoing palliative surgery at Peking University Gastrointestinal Cancer Center, Unit III from January 2016 to October 2018 were retrospectively collected. Postoperative symptomatic relief rate, morbidity of complication within 30 days, complication classification (Clavien-Dindo classification), mortality and survival after operation were analyzed. Kaplan-Meier method was used to evaluate survival and Cox regression analysis was used to identify prognostic factors. Results: Among 46 patients, 30 were male and 16 were female with median age of 63 (19-87) years; 23 patients received stoma/bypass surgery (stoma/bypass group), and 23 cases received tumor debulking surgery (debulking group). The overall symptom relief rate was 76.1% (35/46), while symptom relief rate in the debulking group was 91.3% (21/23), which was significantly higher than 60.9% (14/23) in the stoma/bypass group (χ(2)=4.301, P=0.038). Postoperative complications occurred in 25 patients. The complication rate was 52.2% (12/23) in the debulking group and 56.5% (13/23) in the stoma/bypass group, without statistically significant difference (χ(2)=0.088, P=0.767). Morbidity of complication beyond grade III was 8.7% (2/23) and 13.0% (3/23) in the debulking group and stoma/bypass group respectively, without statistically significant difference (χ(2)=0.224, P=0.636). Four patients died within 30 days after operation, 2 (8.7%) in each group. Twenty-four patients underwent 1-8 cycles of chemotherapy ± targeting therapy (regimens: CapeOX ± Bevacizumab, FOLFOX/FOLFIRI ± Bevacizumab/Cetuximab), including 10 cases in the stoma/bypass group and 14 cases in the debulking group. Two patients of debulking group received postoperative radiotherapy and chemotherapy (50.6 Gy/22 f, with concurrent oral capecitabine). Till the last follow up of April 2019, 34 patients died (34/46, 73.9%) with a median overall survival time of 6.4 months, and the 6-month and 1-year survival rate was 54.5% and 29.2% respectively. The median survival time in the debulking group was significantly longer than that in the stoma/bypass group (11.5 months vs. 5.2 months, χ(2)=5.117, P=0.024). The median survival time of the 35 patients with symptomatic relief after operation was significant longer than that of 11 patients without relief (7.1 months vs 5.1 months, χ(2)=3.844, P=0.050). Multivariate analysis showed stoma/bypass surgery (HR=2.917, 95%CI:1.357-6.269, P=0.006) and greater omental metastasis (HR=4.060, 95%CI:1.419-11.617, P=0.009) were independent risk factors associated with prognosis of patients with MBO caused by peritoneal mCRC. Conclusions: For patients of MBO caused by peritoneal mCRC, tumor debulking surgery may achieve higher symptom relief rate and prolong survival. Greater omental metastasis indicates poor prognosis.

Abstract 453: A circulating tumor cell assay for dynamic assessment of drug sensitivity in metastatic castration-resistant prostate cancer

Background: Tissue-based gene signatures can predict clinical behavior in prostate cancer (PC). Our objective was to extend their application to circulating tumor cells (CTCs) and to show that changes in the signature were associated with changes in clinical behavior.

Methods: Our approach combined the Thermoresponsive(TR)-NanoVelcro CTC purification system with the Nanostring nCounter system for cellular purification and transcriptomic analysis. The Prostate Cancer Classification System (PCS) panel was modified for use in CTCs. We selected 31 blood samples from 23 PC patients receiving androgen receptor signaling inhibitors (ARSI) and measured the PCS1 Z score (probability). These findings were compared with clinical outcome data (responsiveness/resistance).

Results: A modified, 16-gene PCS1 signature was established and validated through a rigorous bioinformatics process. We performed analytical validation of our combined CTC-RNA system to ensure reproducibility and specificity. In patient bloods, ARSI-resistant samples (ARSI-R, n=14) had significantly higher PCS1 Z scores as compared with ARSI-sensitive samples (ARSI-S, n=17) (Rank-sum test, P=0.003). The analyzed bloods contained samples from 8 patients who developed resistance to an ARSI allowing for dynamic measurement of gene expression. Our analysis found that the PCS1 Z score increased at the time that ARSI-resistance emerged (Pairwise T-test, P=0.016).

Conclusions:Using this new methodology, contemporary, clinically-relevant gene signatures such as PCS could be measured non-invasively in CTCs. These findings can be used to relate gene expression to clinical drug response. This approach also allowed for measurement of dynamic variations of gene expression in individual patients over time that correlated to ARSI sensitivity.

Citation Format: Pai-Chi Teng, Yu Jen Jan, Junhee Yoon, Jie-Fu Chen, Pin-Jung Chen, Nu Yao, Shirley Cheng, Amber Lozano, Michael R. Freeman, Sungyong You, Hsian-Rong Tseng, Edwin M. Posadas. A circulating tumor cell assay for dynamic assessment of drug sensitivity in metastatic castration-resistant prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 453.

Abstract 436: Prediction of aggressive disease in metastatic castration-resistant prostate cancer: The role of very small nuclear circulating tumor cells

Background: Circulating tumor cells (CTCs) have arisen as a contemporary noninvasive prognostic biomarker for prostate cancer (PC). Previously, a subgroup of PC CTCs, with particularly small nuclei (&lt;8.54 μm), were found to be correlated with poor prognosis and the emergence of visceral metastases (VM). This subgroup was named very-small nuclear CTCs (vsnCTCs). We proposed vsnCTCs as a biomarker of aggressive disease in metastatic castration-resistant PC (mCRPC). Previous Studies also showed that the disruption of emerin, a linker of nucleoskeleton and cytoskeleton complex proteins, increases the cancer cells' capacity of migration and invasion. We hypothesize that emerin mislocalization is potentially associated with vsnCTC formation and may be a critical step for metastasis.

Methods: 35 blood samples were obtained from PC patients who failed first-line androgen deprivation therapy (ADT) and starting 2nd line treatment with abiraterone, enzalutamide, or taxane-based chemotherapy. Using our NanoVelcro CTC assay, we captured, subclassified, and enumerated the CTCs from patient samples with high-resolution imaging. Survival analyses were performed to exam the correlation between vsnCTC presence and patients’ prognosis. Concurrently, emerin staining was performed and the distribution and expression levels of emerin were analyzed in selected vsnCTC samples.

Results: The presence of one or more vsnCTCs strongly correlated with inferior overall survival (OS), progression free survival (PFS), and time to VM (TTVM). We also observed lower emerin content in vsnCTCs compared to WBC, and more prominent emerin mislocalization in vsnCTCs compared to CTCs with larger nuclei.

Conclusion: Our study strongly demonstrated the importance of morphologic characterization of CTCs and suggested that vsnCTC is a blood-borne biomarker for prediction of aggressive disease. Additionally, emerin mislocalization in vsnCTCs could be a potential biological pathway behind this morphologic phenomenon.

Citation Format: Pin-Jung Chen, Yu Jen Jan, Pai-Chi Teng, Jie-Fu Chen, Shirley Cheng, Nu Yao, Mariana Reis-Sobreiro, Amber Lozano, Amy Gomez, Hsian-Rong Tseng, Michael Freeman, Edwin Posadas. Prediction of aggressive disease in metastatic castration-resistant prostate cancer: The role of very small nuclear circulating tumor cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 436.

Covalent chemistry on nanostructured substrates enables noninvasive quantification of gene rearrangements in circulating tumor cells

Well-preserved mRNA in circulating tumor cells (CTCs) offers an ideal material for conducting molecular profiling of tumors, thereby providing a noninvasive diagnostic solution for guiding treatment intervention and monitoring disease progression. However, it is technically challenging to purify CTCs while retaining high-quality mRNA.Here, we demonstrate a covalent chemistry-based nanostructured silicon substrate ("Click Chip") for CTC purification that leverages bioorthogonal ligation-mediated CTC capture and disulfide cleavage-driven CTC release. This platform is ideal for CTC mRNA assays because of its efficient, specific, and rapid purification of pooled CTCs, enabling downstream molecular quantification using reverse transcription Droplet Digital polymerase chain reaction. Rearrangements of ALK/ROS1 were quantified using CTC mRNA and matched with those identified in biopsy specimens from 12 patients with late-stage non-small cell lung cancer. Moreover, CTC counts and copy numbers of ALK/ROS1 rearrangements could be used together for evaluating treatment responses and disease progression.

["Watch and wait" strategy after neoadjuvant therapy for rectal cancer: status survey of perceptions, attitudes and treatment selection in Chinese surgeons]

Objective: To understand the perceptions, attitudes and treatment selection of Chinese surgeons on the "watch and wait" strategy for rectal cancer patients after achieving a clinical complete response (cCR) following neoadjuvant chemoradiotherapy (nCRT). Methods: A cross-sectional survey was used in this study. Selection of subjects: (1) Domestic public grade III A (provincial and prefecture-level) oncology hospitals or general hospitals possessing the radiotherapy department and the diagnosis and treatment qualifications for colorectal cancer. (2) Surgeons of deputy chief physician or above. Using the "Questionnaire Star" online survey platform to create a questionnaire about cognition, attitude and treatment choice of the "watch and wait" strategy after cCR following nCRT for rectal cancer. The questionnaire contained 32 questions, such as the basic information of doctor, the current status of rectal cancer surgery, the management of pathological complete remission (ypCR) after nCRT for rectal cancer, the selection of examination items for diagnosis of cCR, the selection of suitable people undergoing "watch and wait" approach, the nCRT mode for promotion of cCR, the choice of evaluation time point, the willingness to perform "watch and wait" approach and the treatment choice, and the risk and monitoring of "watch and wait" approach. A total of 116 questionnaires were sent to the respondents via WeChat between January 31 and February 19, 2019. Statistical analysis was performed using Fisher's exact test for categorical variables. Results: Forty-eight hospitals including 116 surgeons meeting criteria were enrolled, of whom 77 surgeons filled the questionnaire with a response rate of 66.4%. "Watch and wait" strategy was carried out in 76.6% (59/77) of surgeons. Seventy surgeons (90.9%) were aware of the ypCR rate of rectal cancer after preoperative nCRT and 49 surgeons (63.6%) knew the 3-year disease-free survival of patients with ypCR in their own hospitals. Fifty-five surgeons (71.4%) believed that patients with ypCR undergoing radical surgery met the treatment criteria and were not over-treated. Three most necessary examinations in diagnosing cCR were colonoscopy (96.1%, 74/77), digital rectal examination (DRE) (90.9%,70/77) and DWI-MRI (83.1%, 64/77). Responders preferred to consider a "watch and wait" strategy for patients with baseline characteristics as mrN0 (77.9%, 60/77), mrT2 (68.8%, 53/77) and well-differentiated adenocarcinoma (68.8%, 53/77). Sixty-six surgeons (85.7%) believed that long-term chemoradiotherapy (LCRT) with combination or without combination of induction and/or consolidation of the CapeOX regimen (capecitabine + oxaliplatin) should be the first choice as a neoadjuvant therapy to achieve cCR. Forty-one surgeons (53.2%) believed that a reasonable interval of judging cCR after nCRT should be ≥ 8 weeks. Forty-four surgeons (57.1%) routinely, or in most cases, informed patient the possibility of cCR and proposed to "watch and wait" strategy in the initial diagnosis of patients with non-metastatic rectal cancer. Thirteen surgeons (16.9%) would take the "watch and wait" strategy as the first choice after the patient having cCR. Fifty-two surgeons (67.5%) would be affected by the surgical method, that was to say, "watch and wait" approach would only be recommended to those patients who would achieve cCR and could not preserve the anus or underwent difficult anus-preservation surgery. Sixteen surgeons (20.8%) demonstrated that "watch and wait" strategy would not be recommended to patients with cCR regardless of whether the surgical procedure involved anal sphincter. Eleven surgeons (14.3%) believed that the main risk of "watch and wait" approach came from distant metastasis rather than local recurrence or regrowth. Twenty-nine of surgeons (37.7%) did not understand the difference between "local recurrence" and "local regrowth" during the period of "watch and wait". Twenty-six surgeons (33.8%) thought that the monitoring interval for the first 3 years of "watch and wait" strategy was 3 months, and the follow-up monitoring interval could be 6 months to 5 years. Surgeons from cancer specialist hospitals had higher approval rate, notification rate, and referral rate of "watch and wait" strategy than those from general hospitals. Thirty-one surgeons (42.5%) considered that the difficulty and concern of carrying out "watch and wait" approach in the future was the disease progress leading to medical disputes. Twenty-six surgeons (35.6%) demonstrated that their concern was lack of uniform evaluation standard for cCR. Conclusions: Chinese surgeons seem to have inadequate knowledge of non-operative management for rectal cancer patients achieving cCR after nCRT and show relatively conservative attitudes toward the strategy. Chinese consensus needs to be formed to guide the non-operative management in selected patients. Chinese Watch & Wait Database (CWWD) is also needed to establish and provide more evidence for the use of alternative procedure after a cCR following nCRT.

A circulating tumor cell specific RNA assay for assessment of androgen receptor signaling inhibitor sensitivity in metastatic castration-resistant prostate cancer

5059

Background: Our objective is to develop a circulating tumor cell (CTC)-RNA assay for characterizing clinically relevant RNA signatures for the assessment of androgen receptor signaling inhibitors (ARSIs) sensitivity in metastatic castration-resistant prostate cancer (mCRPC) patients. Methods: We developed NanoVelcro CTC-RNA Assay by combining Thermoresponsive(TR)-NanoVelcro CTC purification system with NanoString nCounter platform for CTC purification and RNA analysis. Based on the well-validated, tissue-based Prostate Cancer Classification System (PCS), we selected the most aggressive and ARSI-resistant subtype- the PCS1, for CTC analysis. We applied a rigorous bioinformatic process to develop a CTC-PCS1 panel that is specific to PC CTCs. We validated NanoVelcro CTC-RNA Assay and CTC-PCS1 panel with PC cell lines to demonstrate sensitivity and specificity of the PCS1 Z score (the likelihood estimate of the PCS1 subtype) for identifying PCS1 subtype and ARSI resistance. We then selected 31 blood samples from 23 PC patients receiving ARSIs to test in our assay. The PCS1 Z score of each sample was computed and compared with ARSI treatment sensitivity. Results: We established a 16-gene CTC-PCS1 panel that consists of CTC-specific RNA signatures. The validation studies using PC cell lines showed that the assay can detect the RNA transcripts with high sensitivity and scalability in the range of 1-100 cells. We also showed that the genes in CTC-PCS1 panel is highly expressed in PC cells. We further demonstrated that the CTC-PCS1 panel is highly specific in identifying PCS1-like samples, and the high PCS1 Z score is associated with ARSI resistance. In patient bloods, ARSI-resistant samples (ARSI-R, n=14) had significantly higher PCS1 Z scores as compared with ARSI-sensitive samples (ARSI-S, n=17) (Rank-sum test, P=0.003). In 8 patients who were initially sensitive to ARSI (ARSI-S) and later developed resistance (ARSI-R), we found that the PCS1 Z score increased from the time of ARSI-S to the time of ARSI-R (Pairwise T-test, P=0.016). Conclusions: Using our new methodology, we developed a first-in-class CTC-RNA assay and demonstrated the feasibility of transforming clinically-relevant tissue-based RNA profiling into CTC tests. This approach allows for detecting RNA expression relevant to clinical drug resistance in a non-invasive fashion, which can facilitate patient-specific treatment selection and early detection of drug resistance- a goal in precision oncology.

A Circulating Tumor Cell-RNA Assay for Assessment of Androgen Receptor Signaling Inhibitor Sensitivity in Metastatic Castration-Resistant Prostate Cancer

Rationale: Our objective was to develop a circulating tumor cell (CTC)-RNA assay for characterizing clinically relevant RNA signatures for the assessment of androgen receptor signaling inhibitor (ARSI) sensitivity in metastatic castration-resistant prostate cancer (mCRPC) patients. Methods: We developed the NanoVelcro CTC-RNA assay by combining the Thermoresponsive (TR)-NanoVelcro CTC purification system with the NanoString nCounter platform for cellular purification and RNA analysis. Based on the well-validated, tissue-based Prostate Cancer Classification System (PCS), we focus on the most aggressive and ARSI-resistant PCS subtype, i.e., PCS1, for CTC analysis. We applied a rigorous bioinformatic process to develop the CTC-PCS1 panel that consists of prostate cancer (PCa) CTC-specific RNA signature with minimal expression in background white blood cells (WBCs). We validated the NanoVelcro CTC-RNA assay and the CTC-PCS1 panel with well-characterized PCa cell lines to demonstrate the sensitivity and dynamic range of the assay, as well as the specificity of the PCS1 Z score (the likelihood estimate of the PCS1 subtype) for identifying PCS1 subtype and ARSI resistance. We then selected 31 blood samples from 23 PCa patients receiving ARSIs to test in our assay. The PCS1 Z scores of each sample were computed and compared with ARSI treatment sensitivity. Results: The validation studies using PCa cell line samples showed that the NanoVelcro CTC-RNA assay can detect the RNA transcripts in the CTC-PCS1 panel with high sensitivity and linearity in the dynamic range of 5-100 cells. We also showed that the genes in CTC-PCS1 panel are highly expressed in PCa cell lines and lowly expressed in background WBCs. Using the artificial CTC samples simulating the blood sample conditions, we further demonstrated that the CTC-PCS1 panel is highly specific in identifying PCS1-like samples, and the high PCS1 Z score is associated with ARSI resistance samples. In patient bloods, ARSI-resistant samples (ARSI-R, n=14) had significantly higher PCS1 Z scores as compared with ARSI-sensitive samples (ARSI-S, n=17) (Rank-sum test, P=0.003). In the analysis of 8 patients who were initially sensitive to ARSI (ARSI-S) and later developed resistance (ARSI-R), we found that the PCS1 Z score increased from the time of ARSI-S to the time of ARSI-R (Pairwise T-test, P=0.016). Conclusions: Using our new methodology, we developed a first-in-class CTC-RNA assay and demonstrated the feasibility of transforming clinically-relevant tissue-based RNA profiling such as PCS into CTC tests. This approach allows for detecting RNA expression relevant to clinical drug resistance in a non-invasive fashion, which can facilitate patient-specific treatment selection and early detection of drug resistance, a goal in precision oncology.

A noninvasive prognostic biomarker for metastatic castration-resistant prostate cancer: Very small nuclear circulating tumor cells

179

Background: Circulating tumor cells (CTCs) have arisen as a contemporary biomarker for prostate cancer (PC). A subgroup of PC CTCs, with particularly small nuclei ( < 8.54 μm), were found to be correlated with poor prognosis and the emergence of visceral metastases (VM). This subgroup was named very-small nuclear CTCs (vsnCTCs). The findings led us to explore vsnCTCs as an aggressive biomarker in metastatic castration-resistant PC (mCRPC). We also explored a biological pathway that potentially drives this morphologic phenomenon. Studies showed that the disruption of the linker of nucleoskeleton and cytoskeleton (LINC) complex proteins, such as emerin, results in nuclear envelope instability and drives cancer cells to an amoeboid phenotype with increasing capacity of migration and invasion. We hypothesized that emerin mislocalization is associated with vsnCTC formation and may be a critical step of metastasis. Methods: Using our NanoVelcro CTC assay, we are able to capture and enumerate CTCs from patients' blood and correlate this data with clinical outcomes. We collected samples from 35 mCRPC patients who failed first-line androgen deprivation therapy and started treatment with abiraterone, enzalutamide, or taxane-based chemotherapy. Survival analyses were performed to exam the correlation between vsnCTC counts and patients’ prognosis. Concurrently, emerin staining was performed and the distribution and expression levels were analyzed in selected vsnCTC samples. Results: The presence of one or more vsnCTCs correlated with worse overall survival (P = 0.00013), progression free survival (PSA progression: P = 0.012; radiographic progression: P = 0.0015), and faster time to VM (P = 0.024). We also observed lower emerin content in vsnCTCs compared to WBC, and more prominent emerin mislocalization in vsnCTCs compared to CTCs with larger nuclei. Conclusions: Our study demonstrated the importance of morphologic characterization of CTCs and suggested that vsnCTCs is a putative biomarker for prediction of worse outcome. Additionally, our findings of emerin mislocalization in vsnCTCs suggested a potential biological pathway behind this nuclear morphologic phenomenon.

A circulating tumor cell RNA assay for dynamic assessment of androgen receptor signaling inhibitors sensitivity in metastatic castration-resistant prostate cancer

157

Background: Tissue-based gene signatures can predict clinical behavior in prostate cancer (PC). Our objective was to extend their application to circulating tumor cells (CTCs) and to show that changes in the signature were associated with changes in clinical behavior. Methods: Our approach combined the Thermoresponsive(TR)-NanoVelcro CTC purification system with the Nanostring nCounter system for cellular purification and transcriptomic analysis. The Prostate Cancer Classification System (PCS) panel was modified for use in CTCs. We selected 31 blood samples from 23 PC patients receiving androgen receptor signaling inhibitors (ARSI) and measured the PCS1 Z score (probability). These findings were compared with clinical outcome data (responsiveness/resistance). Results: A modified, 16-gene PCS1 signature was established and validated through a rigorous bioinformatics process. We performed analytical validation of our combined CTC-RNA system to ensure reproducibility and specificity. In patient bloods, ARSI-resistant samples (ARSI-R, n = 14) had significantly higher PCS1 Z scores as compared with ARSI-sensitive samples (ARSI-S, n = 17) (Rank-sum test, P = 0.003). The analyzed bloods contained samples from 8 patients who developed resistance to an ARSI allowing for dynamic measurement of gene expression. Our analysis found that the PCS1 Z score increased at the time that ARSI-resistance emerged (Pairwise T-test, P = 0.016). Conclusions: Using this new methodology, contemporary, clinically-relevant gene signatures such as PCS could be measured non-invasively in CTCs. These findings can be used to relate gene expression to clinical drug response. This approach also allowed for measurement of dynamic variations of gene expression in individual patients over time that correlated to ARSI sensitivity.

Environmentally and Mechanically Stable Selenium 1D/2D Hybrid Structures for Broad-Range Photoresponse from Ultraviolet to Infrared Wavelengths

Selenium (Se) is one of the potential candidates as photodetector because of its outstanding properties such as high photoconductivity (∼8 × 10⁴ S cm^-1), piezoelectricity, thermoelectricity, and nonlinear optical responses. Solution phase synthesis becomes an efficient way to produce Se, but a contamination issue that could deteriorate the electric characteristic of Se should be taken into account. In this work, a facile, controllable approach of synthesizing Se nanowires (NWs)/films via a plasma-assisted growth process was demonstrated at the low substrate temperature of 100 °C. The detailed formation mechanisms of nanowires arrays to thin films at different plasma powers were investigated. Moreover, indium (In) layer was used to enhance the adhesive strength with 50% improvement on a SiO₂/Si substrate by mechanical interlocking and surface alloying between Se and In layers, indicating great tolerance for mechanical stress for future wearable devices applications. Furthermore, the direct growth of Se NWs/films on a poly(ethylene terephthalate) substrate was demonstrated, exhibiting a visible to broad infrared detection ranges from 405 to 1555 nm with a high on/off ratio of ∼700 as well as the fast response time less than 25 ms. In addition, the devices exhibited fascinating stability in the atmosphere over one month.

Historical epidemiology of hepatitis C virus in select countries-volume 4

Due to the introduction of newer, more efficacious treatment options, there is a pressing need for policy makers and public health officials to develop or adapt national hepatitis C virus (HCV) control strategies to the changing epidemiological landscape. To do so, detailed, country-specific data are needed to characterize the burden of chronic HCV infection. In this study of 17 countries, a literature review of published and unpublished data on HCV prevalence, viraemia, genotype, age and gender distribution, liver transplants and diagnosis and treatment rates was conducted, and inputs were validated by expert consensus in each country. Viraemic prevalence in this study ranged from 0.2% in Hong Kong to 2.4% in Taiwan, while the largest viraemic populations were in Nigeria (2 597 000 cases) and Taiwan (569 000 cases). Diagnosis, treatment and liver transplant rates varied widely across the countries included in this analysis, as did the availability of reliable data. Addressing data gaps will be critical for the development of future strategies to manage and minimize the disease burden of hepatitis C.

The present and future disease burden of hepatitis C virus infections with today's treatment paradigm: Volume 4

Factors influencing the morbidity and mortality associated with viremic hepatitis C virus (HCV) infection change over time and place, making it difficult to compare reported estimates. Models were developed for 17 countries (Bahrain, Bulgaria, Cameroon, Colombia, Croatia, Dominican Republic, Ethiopia, Ghana, Hong Kong, Jordan, Kazakhstan, Malaysia, Morocco, Nigeria, Qatar and Taiwan) to quantify and characterize the viremic population as well as forecast the changes in the infected population and the corresponding disease burden from 2015 to 2030. Model inputs were agreed upon through expert consensus, and a standardized methodology was followed to allow for comparison across countries. The viremic prevalence is expected to remain constant or decline in all but four countries (Ethiopia, Ghana, Jordan and Oman); however, HCV-related morbidity and mortality will increase in all countries except Qatar and Taiwan. In Qatar, the high-treatment rate will contribute to a reduction in total cases and HCV-related morbidity by 2030. In the remaining countries, however, the current treatment paradigm will be insufficient to achieve large reductions in HCV-related morbidity and mortality.

Strategies to manage hepatitis C virus infection disease burden-Volume 4

The hepatitis C virus (HCV) epidemic was forecasted through 2030 for 17 countries in Africa, Asia, Europe, Latin America and the Middle East, and interventions for achieving the Global Health Sector Strategy on viral hepatitis targets-"WHO Targets" (65% reduction in HCV-related deaths, 90% reduction in new infections and 90% of infections diagnosed by 2030) were considered. Scaling up treatment and diagnosis rates over time would be required to achieve these targets in all but one country, even with the introduction of high SVR therapies. The scenarios developed to achieve the WHO Targets in all countries studied assumed the implementation of national policies to prevent new infections and to diagnose current infections through screening.

[Determination and significance of serum MPO and amylin in adult patients with OSAHS after short-range noninvasive positive pressure ventilation]

Objective:The aim of this study to investigate the determination and significance of serum MPO and amylin in adult patients with OSAHS after short-range noninvasive positive pressure ventilation. Method:Eighty-seven OSAHS patients were divided into severe group (30 cases), moderate group (30 cases) and mild group (27 cases) according to the AHI range. Twenty-seven outpatient health persons were selected as the control group. Serum amylin and myeloperoxidase were measured by ELISA; Amyloid and myeloperoxidase were reassessed in 30 patients with severe OSAHS after 6 months of combined therapy, and the relationship between amylin, myeloperoxidase and PSG was analyzed. Result:①With the severity of OSAHS patients increased, the serum amylin and myeloperoxidase levels gradually increased (F=22.486, 19.755;P<0.01); There was no significant difference in MPO and amylin concentration between the mild group and the control group (P>0.05), and the other groups were significantly different from each other (P<0.01). ②There was no correlation among serum amylin and myeloperoxidase level and BMI and age in OSAHS patients (P>0.05); and a negative correlation with SaO₂, and AHI was positively correlated (P<0.01). ③After 3 months of CPAP treatment, LSaO₂ increased which the AHI and peripheral blood MPO, amylin levels lower than before in 30 patients (P<0.05); The amylin and myeloperoxidase concentrations of blood after 6 months of treatment were significantly lower than those of 3 months after treatment (P<0.05), which still increased compared with the control group. Conclusion:The determination of serum amylin and MPO in patients with OSAHS has a certain reference value in predicting the condition and curative effect of diabetes mellitus and insulin resistance. CPAP treatment can significantly reduce the degree of hypoxiapatients and cardiovascular damage in OSAHS patients, which was significantly correlated with the treatment time.

Annealing Stability Study of Co20Fe60B20\MgO\ Co20Fe60B20 Perpendicular Magnetic Tunnel Junctions

A full Co20Fe60B20\MgO\ Co20Fe60B20 perpendicular magnetic tunnel junction (pMTJ) with (Co\Pt) multilayers as pinning layers and different functional multilayers stacks were made and annealed at different temperatures. The tunneling magnetoresistance ratio (TMR) and MgO barrier resistance-area product (RA) were measured and analyzed as a function of annealing temperature. The TMR of pMTJs dramatically declines with increasing annealing temperatures from 320 °C to 400 °C while the RA increases with temperature from 375 °C to 450 °C. The pMTJs and partial stacks were also measured in a vibrating sample magnetometer (VSM). We found that the (Co\Pt) multilayers are very stable and maintain a magnetization direction perpendicular to the film plane up to 450 °C. However, the magnetization direction of the CoFeB above and below the MgO barrier rotates from perpendicular to in-plane with increasing annealing temperature. Furthermore, the CoFeB layer influences the adjacent (Co\Pt) layers to rotate at the same time. The pMTJs' elemental depth profiles in the as deposited and annealed states were determined by Secondary Ion Mass Spectrometry (SIMS). We found that Boron and Tantalum migrate towards the top of the stack. The other elements (Platinum, Cobalt, Ruthenium, and Magnesium) are very stable and do not interdiffuse during annealing up to 450°C.

Underlayer Effect on Perpendicular Magnetic Anisotropy in Co20Fe60B20\MgO Films

Perpendicular Magnetic Tunneling Junctions (pMTJs) with Ta\CoFeB\MgO have been extensively studied in recent years. However, the effects of the underlayer on the formation of the CoFeB perpendicular magnetic anisotropy (PMA) are still not well understood. Here we report the results of our systematic use of a wide range of elements (Ti, V, Cr, Zr, Nb, Mo, Ru, Rh, Pd, Ag, Hf, Ta, W, Re, Os, Ir, Pt and Au) encompassed by columns IVA, VA, VIA, VIIA and VIIIA of the periodic table as the underlayer in a underlayer\Co₂₀Fe₆₀B₂₀\MgO stack. Our goals were to survey more elements which could conceivably create a PMA in CoFeB and thereby to explore the mechanisms enabling these underlayers to enhance or create the PMA. We found underlayer elements having both an outer shell of 4d electrons (Zr, Nb Mo, and Pd) and 5d electrons (Hf, Ta, W, Re, Ir, and Pt) resulted in the development of a PMA in the MgO-capped Co₂₀Fe₆₀B₂₀. Hybridization between the 3d electrons of the Fe or Co (in the Co₂₀Fe₆₀B₂₀) at the interface with the 4d or 5d electrons of the underlayer is thought to be the cause of the PMA development.

Asian-Pacific clinical practice guidelines on the management of hepatitis B: a 2015 update

Worldwide, some 240 million people have chronic hepatitis B virus (HBV), with the highest rates of infection in Africa and Asia. Our understanding of the natural history of HBV infection and the potential for therapy of the resultant disease is continuously improving. New data have become available since the previous APASL guidelines for management of HBV infection were published in 2012. The objective of this manuscript is to update the recommendations for the optimal management of chronic HBV infection. The 2015 guidelines were developed by a panel of Asian experts chosen by the APASL. The clinical practice guidelines are based on evidence from existing publications or, if evidence was unavailable, on the experts' personal experience and opinion after deliberations. Manuscripts and abstracts of important meetings published through January 2015 have been evaluated. This guideline covers the full spectrum of care of patients infected with hepatitis B, including new terminology, natural history, screening, vaccination, counseling, diagnosis, assessment of the stage of liver disease, the indications, timing, choice and duration of single or combination of antiviral drugs, screening for HCC, management in special situations like childhood, pregnancy, coinfections, renal impairment and pre- and post-liver transplant, and policy guidelines. However, areas of uncertainty still exist, and clinicians, patients, and public health authorities must therefore continue to make choices on the basis of the evolving evidence. The final clinical practice guidelines and recommendations are presented here, along with the relevant background information.

Recombinant MG53 protein modulates therapeutic cell membrane repair in treatment of muscular dystrophy

Mitsugumin 53 (MG53), a muscle-specific TRIM family protein, is an essential component of the cell membrane repair machinery. Here, we examined the translational value of targeting MG53 function in tissue repair and regenerative medicine. Although native MG53 protein is principally restricted to skeletal and cardiac muscle tissues, beneficial effects that protect against cellular injuries are present in nonmuscle cells with overexpression of MG53. In addition to the intracellular action of MG53, injury to the cell membrane exposes a signal that can be detected by MG53, allowing recombinant MG53 protein to repair membrane damage when provided in the extracellular space. Recombinant human MG53 (rhMG53) protein purified from Escherichia coli fermentation provided dose-dependent protection against chemical, mechanical, or ultraviolet-induced damage to both muscle and nonmuscle cells. Injection of rhMG53 through multiple routes decreased muscle pathology in the mdx dystrophic mouse model. Our data support the concept of targeted cell membrane repair in regenerative medicine, and present MG53 protein as an attractive biological reagent for restoration of membrane repair defects in human diseases.

Diet and exercise improve neutrophil to lymphocyte ratio in overweight adolescents

Neutrophil to lymphocyte ratio and levels of pro-inflammatory cytokines were evaluated in overweight, male Chinese adolescents upon completing a 4-week diet and physical exercise intervention. 43 recruited, non-randomized adolescents (body mass index >25 kg/m2) completed the controlled study. Anthropometric and biologic parameters were measured pre- and post-intervention. After the 4-week intervention, participants exhibited a significant decrease in body mass, body mass index, percentage body fat, basal heart rate, diastolic blood pressure, and all body shape indices tested. A significant decrease in serum lipids (except high-density lipoprotein cholesterol) and insulin levels was observed post-intervention. The neutrophil to lymphocyte ratio was significantly lower post-intervention. Bivariate correlation analyses showed that decrement in Δneutrophil to lymphocyte ratio significantly correlated with decrement in Δinterleukin-6 and Δwhite blood cell count. Thus, a 4-week diet and physical exercise intervention significantly reduces the neutrophil to lymphocyte ratio in a population of overweight, male adolescents. Weight loss caused by the intervention was associated with a significant decrease of pro-inflammatory cytokine levels.

On the formation and photoluminescence of Si(1-x)Ge(x) nanoparticles

Si(1-x)Ge(x) nanoparticles were prepared from two annealed alloy ingots at the compositions of Si:Ge = 9.5:0.5 and 9:1 using a vapor condensation technique under Ar atmosphere. These nanoparticles are all spherical, and increasing the working pressure leads to an increased particle size and size dispersion. Comparing to the alloy ingots, the nanoparticles have a higher average content of Ge. In addition, increasing the working pressure also causes the Si(1-x)Ge(x) nanoparticles to become more Ge-rich. This can be ascribed to the lower melting point and higher kinetic energy of Ge than Si during the evaporation process. The photoluminescence of Si(1-x)Ge(x) nanoparticles ranges from visible light to infrared region, and the luminescence peak exhibits a red shift as the Ge content in the nanoparticles increases. This indicates that the incorporation of Ge into Si has a dominant effect in the radiative recombination process, in comparison with the constant luminescence peak position in the case of pure Si nanoparticles with similar size distribution.

Post-translational modification of delta antigen of hepatitis D virus

The hepatitis delta virus (HDV) genome has only one open reading frame, which encodes the viral small delta antigen. After RNA editing, the same open reading frame is extended 19 amino acids at the carboxyl terminus and encodes the large delta antigen. These two viral proteins escort the HDV genome through different cellular compartments for the complicated phases of replication, transcription and, eventually, the formation of progeny virions. To orchestrate these events, the delta antigens have to take distinct cues to traffic to the right compartments and make correct molecular contacts. In eukaryotes, post-translational modification (PTM) is a major mechanism of dictating the multiple functions of a single protein. Multiple PTMs, including phosphorylation, isoprenylation, acetylation, and methylation, have been identified on hepatitis delta antigens. In this chapter we review these PTMs and discuss their functions in regulating and coordinating the life cycle of HDV.

Molecular epidemiology of hepatitis B viral serotypes and genotypes in taiwan

Subtypes of hepatitis B virus (HBV) have specific geographic distributions and can serve as epidemiological markers. The relationship of HBV serotypes and genotypes in Taiwan and their correlation with the domiciles of origin in 122 patients with chronic HBV infection were investigated. The serotype of HBV was determined by comparing the surface gene encoding amino acids 22-148 of the major surface protein with published sequences. Genotyping of HBV was performed by polymerase chain reaction-restriction fragment length polymorphism. Serotype adw accounted for 70% (85/122) of all HBVs, with the remaining belonging to serotype adr. All adr HBVs were genotype C, regardless of the patient's domicile. Of the 85 adw HBVs, 69 (81%) were genotype B, 10 (12%) were genotype C, 5 (6%) were genotype F and only 1 (1%) was genotype A. In the 31 patients originating from mainland China, the prevalence of adr/genotype C was higher than in the 91 Taiwanese patients (15/31 vs. 22/91; p < 0.05). The distribution of the HBV serotypes and genotypes was not significantly different between 17 patients born in Taiwan (6 adw/genotype B, 2 adw/genotype C, 1 adw/genotype F and 8 adr/genotype C) and 14 patients born in mainland China (5 adw/genotype B, 2 adw/genotype C and 7 adr/genotype C). Our results indicate that in Taiwan, most HBVs of serotype adw are genotype B, and all HBVs of serotype adr are genotype C. Patients with origins in mainland China have a higher proportion of serotype adr/genotype C infection.

Improved early detection of cervical intraepithelial lesions by combination of conventional Pap smear and speculoscopy

PURPOSE

To evaluate the efficacy of the addition of speculoscopy to a Pap smear in cervical cancer screening.

METHODS

All women were screened using the Pap smear plus speculoscopy (PapSure) and colposcopy in the multicenter trial. The final diagnosis of each patient was based on a histological evaluation of the colposcopic target biopsy. Results were analyzed using a proportional compare test, sensitivity, specificity and predictive value with significant value determined at less than 0.05.

RESULTS

Of 1,717 eligible cases, 26 cases had LGSIL and 16 cases had HGSIL. Of the Pap smears, five cases had LSIL and 14 cases had HGSIL. Of the combination of the PapSure, 23 cases had LGSIL and 16 cases had HGSIL. The sensitivity of the Pap smear to that of PapSure was calculated at 45.2% and 92.9%, respectively (p < 0.001). The estimated cost to detect a cervical lesion using PapSure is less than that of the Pap smear.

CONCLUSION

The addition of speculoscopy along with a Pap smear screening results in early detection of cervical lesions in comparison to the Pap smear alone. This screening combination is also more cost-effective and requires fewer visits to the clinic in comparison to a Pap smear screening alone.

Molecular epidemiology of hepatitis B viral serotypes and genotypes in taiwan

Subtypes of hepatitis B virus (HBV) have specific geographic distributions and can serve as epidemiological markers. The relationship of HBV serotypes and genotypes in Taiwan and their correlation with the domiciles of origin in 122 patients with chronic HBV infection were investigated. The serotype of HBV was determined by comparing the surface gene encoding amino acids 22-148 of the major surface protein with published sequences. Genotyping of HBV was performed by polymerase chain reaction-restriction fragment length polymorphism. Serotype adw accounted for 70% (85/122) of all HBVs, with the remaining belonging to serotype adr. All adr HBVs were genotype C, regardless of the patient's domicile. Of the 85 adw HBVs, 69 (81%) were genotype B, 10 (12%) were genotype C, 5 (6%) were genotype F and only 1 (1%) was genotype A. In the 31 patients originating from mainland China, the prevalence of adr/genotype C was higher than in the 91 Taiwanese patients (15/31 vs. 22/91; p < 0.05). The distribution of the HBV serotypes and genotypes was not significantly different between 17 patients born in Taiwan (6 adw/genotype B, 2 adw/genotype C, 1 adw/genotype F and 8 adr/genotype C) and 14 patients born in mainland China (5 adw/genotype B, 2 adw/genotype C and 7 adr/genotype C). Our results indicate that in Taiwan, most HBVs of serotype adw are genotype B, and all HBVs of serotype adr are genotype C. Patients with origins in mainland China have a higher proportion of serotype adr/genotype C infection.

Probable reinfection with hepatitis C virus in a chronic hepatitis C patient with a sustained response to combination therapy

Superinfection with hepatitis C virus (HCV) in already chronically infected subjects has been documented. Whether a complete response to antiviral therapy is associated with protective immunity against reinfection with HCV remains unknown. We describe a patient who had a sustained biochemical and virologic response with loss of intrahepatic HCV RNA after a course of combination therapy using interferon plus ribavirin. Histopathologically, the chronic hepatitis was in remission on follow-up biopsy 6 months post-therapy. Unfortunately, 34 weeks post-therapy, a flare of hepatitis with reappearance of hepatitis C viremia was noted 2 months after he received injections from a non-licensed medical provider. Analysis of the core gene sequences showed a 95% homology between the HCV strains isolated before antiviral treatment and during the hepatitis flare. The data indicated that the hepatitis flare after a period of sustained response to combination therapy in this patient could have been caused by reinfection with homotypic HCV. Our observation indicates the lack of protective immunity against reinfection with HCV in patients with chronic hepatitis C, even after successful clearance of the virus. Therefore, reinforcing the education of these subjects to avoid HCV reinfection should be stressed.