Isolated non-immune mediated second-degree atrioventricular block in fetus: natural history and predictive factors for spontaneous recovery

OBJECTIVES

To uncover the clinical course of fetal isolated non-immune mediated second-degree AVB and determine the factors associated with the spontaneous recovery for fetal non-immune second-degree atrioventricular block (AVB).

METHODS

A total of 20 fetuses with isolated, non-immune mediated second-degree AVB were prospectively recruited between 2014 and 2022. These fetuses were divided into the spontaneous recovery group (n=12) and the non-spontaneous recovery group (n=8). Maternal and fetal basic characteristics, intrauterine and postnatal outcomes were compared between groups.

RESULTS

Twelve fetuses restored 1:1 atrioventricular conduction in utero and did not recur during the postnatal follow-up period. The residual eight fetuses maintained as second-degree AVB and six of them were aborted due to parental request in utero. Of the two live children with second-degree AVB, one of them progressed to complete AVB at the latest follow up at the age of 34 months, but without any symptoms, heart enlargement or dysfunction. The residual one progressed to complete AVB and was finally diagnosed with type 2 long-QT syndrome. Fetuses in the spontaneous recovery group presented with earlier gestational age at diagnosis (20.0[17.0-26.0] vs. 24.5[18.0-35.0] weeks, p=0.004) and higher atrial rate (147[130-160] vs 138.00[125.00-149.00] bpm, p=0.006) in comparison with the non-spontaneous recovery group. A cut-off value of 22.5 weeks of gestational age and 144 bpm of atrial rate at diagnosis could predict the failure of spontaneous recovery, with sensitivities of 87.5%, 75%, and specificities of 92.0%, 87.5%, respectively.

CONCLUSIONS

The outcome of fetal non-immune second-degree AVB was favorable. Earlier gestational age at diagnosis and higher atrial rate were related to spontaneous reversion for isolated non-immune-mediated second-degree AVB. However, prenatal gene test should be performed for those with persistent AVB to exclude the heritable disorders including LQTS. These findings may provide important references for clinical management and prenatal counseling. This article is protected by copyright. All rights reserved.

18 F-FDG PET/CT characteristics of IASLC grade 3 invasive adenocarcinoma and the value of 18 F-FDG PET/CT for preoperative prediction: a new prognostication model

OBJECTIVE

This study is performed to investigate the imaging characteristics of the International Association for the Study of Lung Cancer grade 3 invasive adenocarcinoma (IAC) on PET/CT and the value of PET/CT for preoperative predicting this tumor.

MATERIALS AND METHODS

We retrospectively enrolled patients with IAC from August 2015 to September 2022. The clinical characteristics, serum tumor markers, and PET/CT features were analyzed. T test, Mann-Whitney U test, χ 2 test, Logistic regression analysis, and receiver operating characteristic analysis were used to predict grade 3 tumor and evaluate the prediction effectiveness.

RESULTS

Grade 3 tumors had a significantly higher maximum standardized uptake value (SUV max ) and consolidation-tumor-ratio (CTR) ( P  < 0.001), while Grade 1 - 2 tumors were prone to present with air bronchogram sign or vacuole sign ( P  < 0.001). A stepwise logistic regression analysis revealed that smoking history, CEA, SUV max , air bronchogram sign or vacuole sign and CTR were useful predictors for Grade 3 tumors. The established prediction model based on the above 5 parameters generated a high AUC (0.869) and negative predictive value (0.919), respectively.

CONCLUSION

Our study demonstrates that grade 3 IAC has a unique PET/CT imaging feature. The prognostication model established with smoking history, CEA, SUV max , air bronchogram sign or vacuole sign and CTR can effectively predict grade 3 tumors before the operation.

[Short term clinical observation of keratoconus treated with stromal lenticule addition keratoplasty combined with corneal collagen cross-linking]

Objective: To investigate the efficacy of Femtosecond laser-assisted stromal lenticule addition keratoplasty (SLAK) combined with corneal collagen cross-linking (CXL) in the treatment of middle and advanced Keratoconus. Methods: It was a retrospective case series study. Data of 23 cases (24 eyes) of keratoconus treated with femtosecond laser-assisted SLAK combined with CXL in Laser Vision Centre of Xi'an No.1 Hospital from September 2020 to June 2022 were collected, including 16 males and 7 females, aged (23.69±5.18) years. The thickness, diopter number and diameter of the donor corneal stromal lens were assessed. uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), and diopter were recorded before and 1, 3, and 6 months after surgery. Sirius 3D fault corneal topography instrument to measure flat simulated keratometry (Kf), steep simulated keratometry (Ks) and the difference between them (ΔK), as well as central corneal thickness (CCT) and corneal high-order aberration. Results: Six months after surgery, CCT (454.83±50.01) μm were significantly higher than before (384.92±35.45) μm (P<0.05). Six months after surgery, UCVA (1.41±0.32) was significantly lower than before (1.11±0.33)(P<0.05). Six months after surgery, spherical diopter [(-15.73±7.89) D], Kf [(56.82±4.76) D] and Ks [(61.00±4.70) D] were significantly higher than before [(-12.08±5.99) D, (53.55±4.95) D, (58.65±5.10) D] (P<0.05). There was no significant difference in BCVA, column mirror degree and higher order aberrations before and 6 months after surgery(P>0.05). No corneal stromal lens folds, melting and displacement were observed in all eyes during the follow-up period, and no corneal opacity or immune rejection was observed. Conclusions: femtosecond laser-assisted SLAK combined with CXL can significantly increase the corneal thickness of keratoconus and has good effectiveness. In addition, six months of postoperative follow-up of patients showed no significant changes in BCVA and high-order aberrations in the 6 mm central diameter of the cornea, and no postoperative adverse reaction were found in all eyes, indicating that the operation has certain safety.

Focal Brachytherapy for Localized Prostate Cancer: Systematic Review and Meta-Analysis

PURPOSE/OBJECTIVE(S)

Advances in image-guided brachytherapy have increased the interest in focal brachytherapy (F-BT) approaches to optimize disease control, while reducing the toxicities associated whole gland treatments for prostate cancer (PCa). In this study we performed a systematic review to report biochemical control (BC), and genitourinary (GU) and gastrointestinal (GI) toxicity rates in patients with localized prostate cancer treated with F-BT as a definitive or salvage modality.

MATERIALS/METHODS

This project was registered in the PROSPERO database (ID CRD42022320921). A comprehensive literature search was conducted in Cochrane Central databases, Cochrane Database of Systematic Reviews, Embase Classic +Embase, and Medline ALL, all from the OvidSP platform and Web of Science from Clarivate, from each database's inception to July 2022. Search was restricted to English and included terms: focal brachytherapy/prostate cancer, partial brachytherapy/prostate cancer. In total, 14862 articles were identified. Manuscripts that not related to focal or partial prostate brachytherapy, review papers and studies not reporting BC were excluded. After eliminating duplicates, and studies deemed irrelevant by consensus among three independent reviewers, 44 articles remained for in-depth review and data extraction.

RESULTS

Thirty studies that included BC outcomes were included for this analysis, comprising 1556 patients treated with F-BT for PCa. Of these, 1094 (70%) and 462 (30%) underwent F-BT as definitive monotherapy or salvage, respectively; while 585 (38%) and 971 (62%) received HDR or LDR, respectively. For F-BT as monotherapy, the most commonly prescribed dose for HDR was 19 Gy in 1 fraction (range 19-24 Gy), and for LDR, 145 Gy (90-160Gy). Whereas for salvage F-BT, most common dose schedule of HDR was 19Gy in 1 fraction (19-27GY) and LDR 145Gy (144-145Gy). BC random effects estimate for F-BT monotherapy at 1-, 2-, 3-, and 5-years were 100% (P = 1.0), 96% (P = 0.45), 91% (P = 0.45) and 87% (P< 0.01), respectively. Whereas BC random effects estimate for salvage at 1-, 2-, 3-, and 5-years were 91% (P = 0.86), 68% (0.17), and 57% (P = 0.20), respectively. GI and GU grade 3-4 crude toxicity rates for monotherapy and salvage ranged from 0-3.33% and 0-17%, respectively.

CONCLUSION

Over the last decade, there has been increasing interest in F-BT approaches, both as monotherapy and in the salvage setting. BC and toxicity profiles of F-BT appear favorable, and future studies directly comparing with whole-gland treatments are warranted.

[Clinical characteristics of aplastic anemia patients with abnormal autoantibodies and the impact of autoantibodies on immunosuppressive therapy response]

Objective: To investigate the clinical characteristics of patients with acquired aplastic anemia (AA) accompanied by abnormal antinuclear antibody (ANA) and autoantibodies and their effects on the efficacy of immunosuppressive therapy (IST). Method: A retrospective case-control study was conducted, analyzing the clinical data of 291 patients with AA who underwent IST and were screened for autoantibodies at initial diagnosis between January 2018 and December 2019 at Blood Diseases Hospital, Chinese Academy of Medical Sciences. According to the titer of ANA at the initial diagnosis, extracted nuclear antigen antibodies (ENAs) abnormality and the change of ANA titer after treatment, the treatment responses of 3 months and 6 months after IST were compared. The correlation between clinical features and ANA abnormality was analyzed by univariate and multivariate logistic regression analysis. The parameters of univariate analysis P<0.1 were included in multivariate analysis, stepwise regression analysis and subgroup analysis. Results: A total of 291 patients were included in the study, of which 145 (49.83%) were male. Among all patients, 147 (50.52%) tested positive for ANA at initial diagnosis, with titers of 1∶100, 1∶320, and 1∶1 000 observed in 94, 47, and 6 cases, respectively. Female gender, older age, presence of paroxysmal nocturnal hemoglobinuria (PNH) clone, and higher levels of IgG, IgA, and thyroid hormone were significantly associated with ANA positivity at initial diagnosis, while white cell counts, reticulocytes, and free triiodothyronine were significantly lower than that of ANA-negatively patients (all P<0.05). Furthermore, logistic regression analyses revealed that female gender (OR=1.980, 95%CI 1.206-3.277), older age (OR=1.017, 95%CI 1.003-1.032), and presence of PNH clone (OR=1.875, 95%CI 1.049-3.408) were independent risk factors for ANA positivity at initial diagnosis. Subgroup analysis indicated that the risk of ANA positivity at initial diagnosis was even higher in PNH clone-positive patients in the subgroups of females (OR=1.24, 95%CI 1.02-1.51), severe AA (OR=1.26, 95%CI 1.07-1.47), and age≥40 years (OR=1.26, 95%CI 1.05-1.52) (all P<0.05). However, ANA titers at initial diagnosis, presence of other abnormal ENAs, and changes in ANA titers after treatment with IST were not correlated with treatment response (all P>0.05). Conclusions: Approximately 50% of patients with AA had abnormal ANA, and their presence was significantly associated with female gender, older age, and presence of PNH clone at initial diagnosis. However, the presence of abnormal ANA and changes in ANA titers after treatment did not affect the efficacy of IST in patients with AA.

A proper protocol for routine 18F-FDG uEXPLORER total-body PET/CT scans

BACKGROUND

Conventional clinical PET scanners typically have an axial field of view (AFOV) of 15-30 cm, resulting in limited coverage and relatively low photon detection efficiency. Taking advantage of the development of long-axial PET/CT, the uEXPLORER PET/CT scanner with an axial coverage of 194 cm increases the effective count rate by approximately 40 times compared to that of conventional PET scanners. Ordered subset expectation maximization (OSEM) is the most widely used iterative algorithm in PET. The major drawback of OSEM is that the iteration process must be stopped before convergence to avoid image degradation due to excessive noise. A new Bayesian penalized-likelihood iterative PET reconstruction, named HYPER iterative, was developed and is now available on the uEXPLORER total-body PET/CT, which incorporates a noise control component by using a penalty function in each iteration and finds the maximum likelihood solution through repeated iterations. To date, its impact on lesion visibility in patients with a full injected dose or half injected dose is unclear. The goal of this study was to determine a proper protocol for routine 18F-FDG uEXPLORER total-body PET/CT scans.

RESULTS

The uEXPLORER total-body PET/CT images reconstructed using both OSEM and HYPER iterative algorithms of 20 tumour patients were retrospectively reviewed. The quality of the 5 min PET image was excellent (score 5) for all of the dose and reconstruction methods. Using the HYPER iterative method, the PET images reached excellent quality at 1 min with full-dose PET and at 2 min with half-dose PET. The PET image reached a similar excellent quality at 2 min with a full dose and at 3 min with a half dose using OSEM. The noise in the OSEM reconstruction was higher than that in the HYPER iterative. Compared to OSEM, the HYPER iterative had a slightly higher SUVmax and TBR of the lesions for large positive lesions (≥ 2 cm) (SUVmax: up to 9.03% higher in full dose and up to 12.52% higher in half dose; TBR: up to 8.69% higher in full dose and up to 23.39% higher in half dose). For small positive lesions (≤ 10 mm), the HYPER iterative had an obviously higher SUVmax and TBR of the lesions (SUVmax: up to 45.21% higher in full dose and up to 74.96% higher in half dose; TBR: up to 44.91% higher in full dose and up to 93.73% higher in half dose).

CONCLUSIONS

A 1 min scan with a full dose and a 2 min scan with a half dose are optimal for clinical diagnosis using the HYPER iterative and 2 min and 3 min for OSEM. For quantification of the small lesions, HYPER iterative reconstruction is preferred.

Fiber reinforced hydrated networks recapitulate the poroelastic mechanics of articular cartilage

The role of poroelasticity on the functional performance of articular cartilage has been established in the scientific literature since the 1960s. Despite the extensive knowledge on this topic there remain few attempts to design for poroelasticity and to our knowledge no demonstration of an engineered poroelastic material that approaches the physiological performance. In this paper, we report on the development of an engineered material that begins to approach physiological poroelasticity. We quantify poroelasticity using the fluid load fraction, apply mixture theory to model the material system, and determine cytocompatibility using primary human mesenchymal stem cells. The design approach is based on a fiber reinforced hydrated network and uses routine fabrication methods (electrohydrodynamic deposition) and materials (poly[ɛ-caprolactone] and gelatin) to develop the engineered poroelastic material. This composite material achieved a mean peak fluid load fraction of 68%, displayed consistency with mixture theory, and demonstrated cytocompatibility. This work creates a foundation for designing poroelastic cartilage implants and developing scaffold systems to study chondrocyte mechanobiology and tissue engineering. STATEMENT OF SIGNIFICANCE: Poroelasticity drives the functional mechanics of articular cartilage (load bearing and lubrication). In this work we develop the design rationale and approach to produce a poroelastic material, known as a fiber reinforced hydrated network (FiHy™), that begins to approach the native performance of articular cartilage. This is the first engineered material system capable of exceeding isotropic linear poroelastic theory. The framework developed here enables fundamental studies of poroelasticity and the development of translational materials for cartilage repair.

Noninvasive imaging of FAP expression using positron emission tomography: A comparative evaluation of a [18F]-labeled glycopeptide-containing FAPI with [18F]FAPI-42

PURPOSE

Research on fibroblast activating protein (FAP)-targeting inhibitor (FAPI) has become an important focus for cancer imaging and radiotherapy. Quinoline-based tracers [68 Ga]FAPI-04 and [18F]FAPI-42 have been widely used for positron emission tomography (PET) imaging of most tumors. However, there exist some limitations of these tracers with high uptake in biliary duct system and unstable uptake in pancreas, unsuitable for abdominal tumors PET imaging. Here we developed a [18F]-labeled glycopeptide-containing FAPI tracer (named [18F]FAPT) for PET imaging of FAP in cancers.

METHODS

[18F]FAPT was synthesized manually and automatically. The competitive binding to FAP, cellular internalization, and efflux characteristics were examined in vitro using A549-FAP cells. Dynamic MicroPET and biodistribution studies of [18F]FAPT were then conducted in A549-FAP and U87MG xenograft tumor mouse models compared with [18F]FAPI-42. Five healthy volunteers and three patients with cancer underwent [18F]FAPT PET/CT.

RESULTS

Preclinical and clinical studies showed specific binding of [18F]FAPT to FAP and favorable pharmacokinetic properties with better hydrophilicity, lower uptake in biliary duct system, higher tumor uptake and longer tumor retention compared with [18F]FAPI-42. The biodistribution of [18F]FAPT in healthy volunteers and patients with cancer displayed low uptake in most normal tissues except for pancreas, thyroid and salivary gland, which could contribute to high tumor-to-background ratios in most cancers.

CONCLUSION

[18F]FAPT is better PET tracer than [18F]FAPI-42 for imaging of biliary duct system cancer, potentially providing a tool to examine FAP expression in most cancers with high tumor-to-background ratios.

Genomic Complexity Predicts Resistance to Endocrine Therapy and CDK4/6 Inhibition in Hormone Receptor-Positive (HR+)/HER2-Negative Metastatic Breast Cancer

PURPOSE

Clinical biomarkers to identify patients unlikely to benefit from CDK4/6 inhibition (CDK4/6i) in combination with endocrine therapy (ET) are lacking. We implemented a comprehensive circulating tumor DNA (ctDNA) analysis to identify genomic features for predicting and monitoring treatment resistance.

EXPERIMENTAL DESIGN

ctDNA was isolated from 216 plasma samples collected from 51 patients with hormone receptor-positive (HR+)/HER2-negative (HER2-) metastatic breast cancer (MBC) on a phase II trial of palbociclib combined with letrozole or fulvestrant (NCT03007979). Boosted whole-exome sequencing (WES) was performed at baseline and clinical progression to evaluate genomic alterations, mutational signatures, and blood tumor mutational burden (bTMB). Low-pass whole-genome sequencing was performed at baseline and serial timepoints to assess blood copy-number burden (bCNB).

RESULTS

High bTMB and bCNB were associated with lack of clinical benefit and significantly shorter progression-free survival (PFS) compared with patients with low bTMB or low bCNB (all P < 0.05). Dominant APOBEC signatures were detected at baseline exclusively in cases with high bTMB (5/13, 38.5%) versus low bTMB (0/37, 0%; P = 0.0006). Alterations in ESR1 were enriched in samples with high bTMB (P = 0.0005). There was a high correlation between bTMB determined by WES and bTMB determined using a 600-gene panel (R = 0.98). During serial monitoring, an increase in bCNB score preceded radiographic progression in 12 of 18 (66.7%) patients.

CONCLUSIONS

Genomic complexity detected by noninvasive profiling of bTMB and bCNB predicted poor outcomes in patients treated with ET and CDK4/6i and identified early disease progression before imaging. Novel treatment strategies including immunotherapy-based combinations should be investigated in this population.

[Clinical and gene mutation characteristics of patients with hereditary ellipsocytosis: nine cases report and literature review]

Objective: To report gene mutations in nine patients with hereditary elliptocytosis (HE) and analyze the characteristics of pathogenic gene mutations in HE. Methods: The clinical and gene mutations of nine patients clinically diagnosed with HE at Institute of Hematology & Blood Diseases Hospital from June 2018 to February 2022 were reported and verified by next-generation sequencing to analyze the relationship between gene mutations and clinical phenotypes. Results: Erythrocyte membrane protein gene mutations were detected among nine patients with HE, including six with SPTA1 mutation, one with SPTB mutation, one with EPB41 mutation, and one with chromosome 20 copy deletion. A total of 11 gene mutation sites were involved, including 6 known mutations and 5 novel mutations. The five novel mutations included SPTA1: c.1247A>C (p. K416T) in exon 9, c.1891delG (p. A631fs*17) in exon 15, E6-E12 Del; SPTB: c.154C>T (p. R52W) ; and EPB41: c.1636A>G (p. I546V) . Three of the six patients with the SPTA1 mutation were SPTA1 exon 9 mutation. Conclusion: SPTA1 is the most common mutant gene in patients with HE.

Abstract 6685: Targeted liquid biopsy mutation profiling and genome-wide cfDNA copy-number landscape in 3000 samples from six major cancer indications

Introduction. PredicineCARE is a CLIA-certified targeted next-generation sequencing (NGS) assay that provides comprehensive, non-invasive genomic profiling of circulating tumor DNA (ctDNA) in blood and urine. Here we present liquid biopsy mutational profiles and genome-wide cell-free DNA (cfDNA) copy-number burden levels for historical cancer cohorts analyzed with PredicineCARE. We include a total of 3,147 samples from six major cancer indications: prostate (n=1681), lung (n=630), breast (n=300), colorectal (n=217), pancreatic (n=190), and bladder (n=129).

Methods. PredicineCARE employs a 152 targeted gene panel covering all major guideline-recommended alterations for patient care and clinical drug development including targeted therapies and immunotherapies. The assay detects single nucleotide variants (SNVs), small insertions and deletions, gene-level copy number loss/gain, and targeted re-arrangements/fusions. Concurrent low-pass whole-genome sequencing (without the need for additional sample volume) is performed to measure blood-based genome-wide copy-number burden (bCNB) and tumor fraction, providing important complementary molecular insights to variant detection.

Results. We present data from a representative cohort of blood and urine samples processed at Predicine lab in Hayward California (n=3,147). Sequencing was performed using a minimum of 5 ng total cfDNA input from 1-5 mL of plasma or 20-40mL of urine, at one or more clinical timepoints per patient. Samples were sequenced at ~20,000X target panel coverage and the majority also had ~2.5X low-pass whole genome sequencing. Using the Predicine in-house DeepSea bioinformatics pipeline, we report variants as low as 0.05% allele frequency and estimate genome-wide CNVs and bCNB from low-pass data. We compare the mutational and CNV profiles of important genes in each liquid biopsy cancer cohort to variants reported in solid tumor tissues from several large public data sets including Project GENIE (n=71,817 patients) and 136 additional study programs including TCGA (n=38,619 patients, www.cBioPortal.org).

Conclusion. PredicineCARE is a highly sensitive and robust assay for detecting cancer variants in blood and urine. The cfDNA mutation profiles are mostly consistent with public tissue datasets. A small but significant portion of the detected ctDNA variants have been shown to be important for treatment selection or are currently being tested for targeted drug development. Increased bCNB provides a useful measure to monitor treatment response and disease progression. PredicineCARE has been CE-marked and received breakthrough device designation from FDA. A harmonized PredicineCARE assay is available in the US and China to support patient testing in the clinic, global clinical trials and CDx development.

Citation Format: Billie Gould, Lu Tan, Chao Dai, Tiantian Zheng, Wei Mo, Xianghong Wang, Michael Sneddon, Shidong Jia, Kemin Zhou, Pan Du. Targeted liquid biopsy mutation profiling and genome-wide cfDNA copy-number landscape in 3000 samples from six major cancer indications [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6685.

Abstract 6562: Comparative analysis of blood-based tumor fraction estimation in 300 cancer patients

Introduction Tumor fraction (TF) in cell-free DNA is an important known biomarker for monitoring treatment response and disease progression. cfDNA TF is usually estimated by variant allele frequency (VAF) of somatic mutations or copy number variation (CNV). cfDNA assays provide high VAF detection sensitivity by using deep sequencing depth based on target panels, which often makes TF underestimated due to limited panel gene coverage. Also because the interference of copy number changes and lack of matched normal, the VAF estimation is often inaccurate. On the other hand, although CNV based TF estimation does not require matched normal samples, it has lower detection sensitivity and underestimates cfDNA TF for patients without copy number changes. Importantly, tumor heterogeneity exists in many clinical cancer patient samples, where tumor DNA has complex subclone structures, which makes accurate TF estimation even more challenging.

Methods Here we performed comprehensive concordance study of cfDNA TF estimation, by applying both PredicineWES+ (20,000x sequencing depth in boosted cancer-related genes and 2,500x depth in rest exome regions) and PredicineCNB (LP-WGS with 3 × sequencing depth) on more than 300 plasma samples from cancer patients. Using a proprietary algorithm, we calculated TF by integrating PredicineWES+ derived VAFs and PredicineCNB derived CNVs for each sample, where tumor subcloning was taken into the consideration. We implemented proprietary EM algorithm to infer subclone populations, where CNV has high concordance with TF in each subclone.

Results Our study showed that CNV-based TF estimation is highly concordance with VAF-based TF from PredicineWES+ (correlation coefficient &gt; 0.8) when TF is &gt;5%. For clinical samples with &lt; 5% TF inferred from PredicineCNB, we used VAF-based TF. We developed an integrated TF estimation methodology by leveraging molecular insights derived from PredicineWES+ and PredicineCNB, and further performed clinical evaluation study using 50 longitudinal plasma samples from prostate cancer patients that are under different cancer stages or therapies. Our results demonstrated that the integrated TF estimation shows a positive correlation with therapy response and disease stage revealed by CT scan. Finally, serial analysis of plasma cfDNA demonstrated an increase in ctDNA TF and cancer variants, preceding evidence of radiographic and clinical disease progression in many patients.

Conclusion We conducted a comprehensive concordance study to infer cfDNA TF using PredicineWES+ and PredicineCNB in more than 300 patient samples. Our study demonstrated its clinical utility where the integrated TF analysis may provide a more robust and accurate estimation of disease burden in cancer patients.

Citation Format: Chao Dai, Tiantian Zheng, Xiaoxi Dong, Wei Mo, Xiaohong Wang, Shujun Luo, Kemin Zhou, Shidong Jia, Pan Du. Comparative analysis of blood-based tumor fraction estimation in 300 cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6562.

[The effect of on-demand glucocorticoid strategy on the occurrence and outcome of p-ALG-associated serum sickness in aplastic anemia]

Objective: To investigate the effect of on-demand glucocorticoid strategy on the occurrence and outcome of porcine anti-lymphocyte globulin (p-ALG) -associated serum sickness in aplastic anemia (AA) . Methods: The data of AA patients who received in the Anemia Diagnosis and Treatment Center of Haematology Hospital, CAMS & PUMC from January 2019 to January 2022 were collected. Among them, 35 patients were enrolled in the on-demand group, with the glucocorticoid strategy adjusted based on the occurrence and severity of serum sickness; 105 patients were recruited in the usual group by matching the age and disease diagnosis according to 1∶3 ratio in patients who received a conventional glucocorticoid strategy in the same period. The incidences, clinical manifestations, treatment outcomes of serum sickness, and glucocorticoid dosage between the two groups were analyzed. Results: The incidences of serum sickness in the on-demand group and the usual group were 65.7% and 54.3% (P=0.237) , respectively. The median onset of serum sickness was the same [12 (9, 13) d vs the 12 (10, 13) d, P=0.552], and clinical symptoms and signs, primarily joint, and/or muscle pain, fever, and rash were similar. Severity grades were both dominated by Grades 1-2 (62.8% vs 51.4%) , with only a few Grade 3 (2.9% vs 2.9%) , and no Grades 4-5. No significant difference in the serum sickness distribution (P=0.530) . The median duration of serum sickness was the same [5 (3, 7) d vs 5 (3, 6) d, P=0.529], and all patients were completely cured after glucocorticoid therapy. In patients without serum sickness, the average dosage of prophylactic glucocorticoid per patient in the usual group was (469.48 ±193.57) mg (0 in the on-demand group) . When compared to the usual group, the average therapeutic glucocorticoid dosage per patient in the on-demand group was significantly lower [ (125.91±77.70) mg vs (653.90±285.56) mg, P<0.001]. Conclusions: In comparison to the usual glucocorticoid strategy, the on-demand treatment strategy could significantly reduce glucocorticoid dosage without increasing the incidence of serum sickness; in addition, the duration of serum sickness and the incidence of above Grade 2-serum sickness were similar.

[Metagenomic next-generation sequencing of plasma for the identification of bloodstream infectious pathogens in severe aplastic anemia]

Objective: To analyze the diagnostic value of cell-free plasma metagenomic next-generation sequencing (mNGS) pathogen identification for severe aplastic anemia (SAA) bloodstream infection. Methods: From February 2021 to February 2022, mNGS and conventional detection methods (blood culture, etc.) were used to detect 33 samples from 29 consecutive AA patients admitted to the Anemia Diagnosis and Treatment Center of the Hematology Hospital of the Chinese Academy of Medical Sciences to assess the diagnostic consistency of mNGS and conventional detection, as well as the impact on clinical treatment benefits and clinical accuracy. Results: ①Among the 33 samples evaluated by mNGS and conventional detection methods, 25 cases (75.76%) carried potential pathogenic microorganisms. A total of 72 pathogenic microorganisms were identified from all cases, of which 65 (90.28%) were detected only by mNGS. ②All 33 cases were evaluated for diagnostic consistency, of which 2 cases (6.06%) were Composite, 18 cases (54.55%) were mNGS only, 2 cases (6.06%) were Conventional method only, 1 case (3.03%) was both common compliances (mNGS/Conventional testing) , and 10 cases (30.3%) were completely non-conforming (None) . ③All 33 cases were evaluated for clinical treatment benefit. Among them, 8 cases (24.24%) received Initiation of targeted treatment, 1 case (3.03%) received Treatment de-escalation, 13 cases (39.39%) received Confirmation, and the remaining 11 cases (33.33%) received No clinical benefit. ④ The sensitivity of 80.77%, specificity of 70.00%, positive predictive value of 63.64%, negative predictive value of 84.85%, positive likelihood ratio of 2.692, and negative likelihood ratio of 0.275 distinguished mNGS from conventional detection methods (21/12 vs 5/28, P<0.001) . Conclusion: mNGS can not only contribute to accurately diagnosing bloodstream infection in patients with aplastic anemia, but can also help to guide accurate anti-infection treatment, and the clinical accuracy is high.

Association of pectoralis muscle area on computed tomography with airflow limitation severity and respiratory outcomes in COPD: A population-based prospective cohort study

BACKGROUND

Previous studies have shown that patients with chronic obstructive pulmonary disease (COPD) of severe or very severe airflow limitation have a reduced pectoralis muscle area (PMA), which is associated with mortality. However, whether patients with COPD of mild or moderate airflow limitation also have a reduced PMA remains unclear. Additionally, limited evidence is available regarding the associations between PMA and respiratory symptoms, lung function, computed tomography (CT) imaging, lung function decline, and exacerbations. Therefore, we conducted this study to evaluate the presence of PMA reduction in COPD and to clarify its associations with the referred variables.

METHODS

This study was based on the subjects enrolled from July 2019 to December 2020 in the Early Chronic Obstructive Pulmonary Disease (ECOPD) study. Data including questionnaire, lung function, and CT imaging were collected. The PMA was quantified on full-inspiratory CT at the aortic arch level using predefined -50 and 90 Hounsfield unit attenuation ranges. Multivariate linear regression analyses were performed to assess the association between the PMA and airflow limitation severity, respiratory symptoms, lung function, emphysema, air trapping, and the annual decline in lung function. Cox proportional hazards analysis and Poisson regression analysis were used to evaluate the PMA and exacerbations after adjustment.

RESULTS

We included 1352 subjects at baseline (667 with normal spirometry, 685 with spirometry-defined COPD). The PMA was monotonically lower with progressive airflow limitation severity of COPD after adjusting for confounders (vs. normal spirometry; Global Initiative for Chronic Obstructive Lung Disease [GOLD] 1: β=-1.27, P=0.028; GOLD 2: β=-2.29, P<0.001; GOLD 3: β=-4.88, P<0.001; GOLD 4: β=-6.47, P=0.014). The PMA was negatively associated with the modified British Medical Research Council dyspnea scale (β=-0.005, P=0.026), COPD Assessment Test score (β=-0.06, P=0.001), emphysema (β=-0.07, P<0.001), and air trapping (β=-0.24, P<0.001) after adjustment. The PMA was positively associated with lung function (all P<0.05). Similar associations were discovered for the pectoralis major muscle area and pectoralis minor muscle area. After the 1-year follow-up, the PMA was associated with the annual decline in the post-bronchodilator forced expiratory volume in 1 s percent of predicted value (β=0.022, P=0.002) but not with the annual rate of exacerbations or the time to first exacerbation.

CONCLUSION

Patients with mild or moderate airflow limitation exhibit a reduced PMA. The PMA is associated with airflow limitation severity, respiratory symptoms, lung function, emphysema, and air trapping, suggesting that PMA measurement can assist with COPD assessment.

Clinical applications of urine- and blood-based genome wide copy number study from 1,000 patients with bladder and prostate cancer

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Background: Liquid biopsy has become increasingly important in cancer diagnosis and disease progression monitoring. Copy number variation is an important characteristic for genitourinary cancer and many other cancer types, where bladder cancer was shown to have the largest copy number alternation among 33 human cancer types from TCGA. We developed PredicineCNB, a companion LP-WGS assay to robustly estimate genome-wide copy number burden (CNB) from plasma and urine clinical samples, which can provide longitudinal disease monitoring in a cost-effective way. Methods: By integrating both fragments coverage and fragments length from LP-WGS data, and quantifying copy number deviation at chromosome arm level, we greatly increase both sensitivity and specificity for CNB based cancer detection. Analytical evaluation was performed based on clinical plasma titration samples, and PredicineCNB has demonstrated high cancer detection sensitivity (LOD is 1%) with high specificity (> 99%), using DNA input amounts as low as 1ng. We also validated CNB using Predicine panel-based tumor fraction for more than 200 clinical samples, results demonstrated both are highly concordant with correlation coefficient 0.84. Results: We performed clinical evaluation of PredicineCNB on 700 patients with prostate cancer and 300 patients with bladder cancer. For clinical patients with longitudinal samples under different disease stages or drug treatments, we demonstrated a promising potential using PredicineCNB for monitoring dynamic changes in ctDNA, that are caused by copy number variation. For 12 different bladder cancer patients, each with at least two longitudinal samples, we observed that CNB declines as early as two weeks after treatment initiation, providing an early signal of molecular response to therapy. In addition, when comparing conventional radiology-based imaging with CNB, we found that an increase in CNB preceded clinical progression of disease in majority of patients; and CNB shows a positive correlation between cancer stage revealed by CT scan. Conclusions: We conducted a comprehensive clinical study using PredicineCNB in 1,000 patients with prostate and bladder cancers, demonstrating the promising clinical application of liquid biopsy-based genome-wide copy number changes in therapy monitoring.

Monobody adapter for functional antibody display on nanoparticles for adaptable targeted delivery applications

Vascular endothelial cells (ECs) play a central role in the pathophysiology of many diseases. The use of targeted nanoparticles (NPs) to deliver therapeutics to ECs could dramatically improve efficacy by providing elevated and sustained intracellular drug levels. However, achieving sufficient levels of NP targeting in human settings remains elusive. Here, we overcome this barrier by engineering a monobody adapter that presents antibodies on the NP surface in a manner that fully preserves their antigen-binding function. This system improves targeting efficacy in cultured ECs under flow by >1000-fold over conventional antibody immobilization using amine coupling and enables robust delivery of NPs to the ECs of human kidneys undergoing ex vivo perfusion, a clinical setting used for organ transplant. Our monobody adapter also enables a simple plug-and-play capacity that facilitates the evaluation of a diverse array of targeted NPs. This technology has the potential to simplify and possibly accelerate both the development and clinical translation of EC-targeted nanomedicines.

Superiority of [68Ga]Ga-FAPI-04/[18F]FAPI-42 PET/CT to [18F]FDG PET/CT in delineating the primary tumor and peritoneal metastasis in initial gastric cancer

OBJECTIVE

This study aimed to compare [⁶⁸Ga]Ga-FAPI-04/[¹⁸F]FAPI-42 PET/CT with [¹⁸F]FDG PET/CT in the evaluation of initial gastric cancer.

METHODS

We retrospectively compared [⁶⁸Ga]Ga-FAPI-04/[¹⁸F]FAPI-42 PET/CT with [¹⁸F]FDG PET/CT in patients with initial gastric cancer from September 2020 to March 2021. Lesion detectability and the uptake of lesions quantified by the maximum standardized uptake value (SUVmax) and target-to-background ratio (TBR) were compared between the two modalities using the Wilcoxon signed-rank test, Mann-Whitney U test, and McNemar's chi-square test.

RESULTS

A total of 61 patients (37 males, aged 23-81 years) were included, of which 22 underwent radical gastrectomy. For primary lesions, higher uptake of [⁶⁸Ga]Ga-FAPI-04/[¹⁸F]FAPI-42 was observed compared to [¹⁸F]FDG (median SUVmax, 14.60 vs 4.35, p < 0.001), resulting in higher positive detection using [⁶⁸Ga]Ga-FAPI-04/[¹⁸F]FAPI-42 PET/CT than [¹⁸F]FDG PET/CT (95.1% vs 73.8%, p < 0.001), particularly for tumors with signet-ring cell carcinoma (SRCC) (96.4% vs 57.1%, p < 0.001). [⁶⁸Ga]Ga-FAPI-04/[¹⁸F]FAPI-42 PET/CT detected more positive lymph nodes than [¹⁸F]FDG PET/CT (637 vs 407). However, both modalities underestimated N staging compared to pathological N staging. [⁶⁸Ga]Ga-FAPI-04/[¹⁸F]FAPI-42 PET/CT showed a higher sensitivity (92.3% vs 53.8%, p = 0.002) and peritoneal cancer index score (18 vs 3, p < 0.001) in peritoneum metastasis and other suspect metastases compared to [¹⁸F]FDG PET/CT.

CONCLUSION

Our findings indicate that [⁶⁸Ga]Ga-FAPI-04/[¹⁸F]FAPI-42 PET/CT outperformed [¹⁸F]FDG PET/CT in the evaluation of primary tumors with SRCC and peritoneum metastasis in initial gastric cancer. However, no clinically useful improvement was seen in N staging.

KEY POINTS

• The uptake of [⁶⁸Ga]Ga-FAPI-04/[¹⁸F]FAPI-42 in primary tumor and metastasis was intensely higher than that of [¹⁸F]FDG (p < 0.001) in 61 patients with initial gastric cancer. • [⁶⁸Ga]Ga-FAPI-04/[¹⁸F]FAPI-42 PET/CT had a higher sensitivity detection in primary tumors (95.1% vs 73.8%, p < 0.001) and peritoneal metastases (92.3% vs 53.8%, p = 0.002) than [¹⁸F]FDG PET/CT. • [⁶⁸Ga]Ga-FAPI-04/[¹⁸F]FAPI-42 PET/CT depicted more positive lymph nodes than [¹⁸F]FDG PET/CT (637 vs 407); however, both underestimated N staging compared to pathological N staging.

[Intermediate-risk prostate cancer treated with exclusive external irradiation: Focus on anatomical sites of recurrence in two French trials]

PURPOSE

Retrospective description of anatomical sites of relapse based on (18F)-choline PET-CT, (68Ga)-prostatic specific-membrane antigen PET-CT, bone scan, and prostate magnetic resonance imaging (MRI) data.

MATERIALS AND METHODS

From two French prospective cohorts, patients treated with exclusive radiotherapy for an intermediate-risk cancer were identified during their follow-ups. They were included if they presented a rising of the prostate-specific antigen (PSA) associated with the realization of an imaging showing the sites of recurrences.

RESULTS

Two hundred and sixty-three patients were included. After a median follow-up of 76 months (interquartile range [IQR] 67-95), 65 patients had biochemical recurrence and positive imaging. The median nadir PSA was 0.6ng/mL and the median PSA at recurrence was 3.4ng/mL. A single lesion was found in 48% of cases, 2 to 4 lesions in 43% of cases and more than 4 lesions in 9% of cases. The sites of relapse identified were prostate (37/65), prostate only (19/65), seminal vesicles (9/65) Pelvic nodes (35/65), extrapelvic nodes (15/65) and bone (13/65).

CONCLUSIONS

The majority of relapses presented as a single lesion localized in the pelvis.

MicroRNA-4463 facilitates the development of colon cancer by suppression of the expression of PPP1R12B

PURPOSE

In the present work, we investigated the expression pattern of miR-4463 in the non-metastasis and metastasis colorectal cancer (CRC) patients and its regulation axis.

METHODS

RT-qPCR assay was performed to assess miR-4463 expression in the serum and tissues of patients with non-metastasis and metastasis, and in the CRC cell lines. MTT assay, colony formation assay, transwell assay, and flow cytometry assay were used to examine the role of miR-4463 in CRC cell viability, proliferation, and migration. Bioinformatic analysis was used to identify the potential target gene of miR-4463, and the targeting relationship between miR-4463 and PPP1R12B was verified in vitro using dual luciferase assay. Western blotting assay was used to determine the protein level of the target gene PPP1R12B in CRC cells under the transfections of miR-4463 mimic, inhibitor and vectors overexpressing PPP1R12B.

RESULTS

miR-4463 was markedly increased in the non-metastasis CRC tissues, and increased even higher in the metastasis CRC tissues, while miR-4463 expression had no significant difference in serum from non-metastasis and metastasis CRC samples. Besides, miR-4463 was upregulated in CRC cell lines. Functionally, miR-4463 promoted CRC cell proliferation, migration, and inhibiting cell apoptosis. Further analysis revealed that the miR-4463/PPP1R12B axis was responsible for the role of this miRNA.

CONCLUSION

We reported the roles of miR-4463 in CRC proliferation and migration, supporting that miR-4463 could be a potential predictive diagnostic marker for colon cancer.

[Reassessing the six months prognosis of patients with severe or very severe aplastic anemia without hematological responses at three months after immunosuppressive therapy]

Objective: To reassess the predictors for response at 6 months in patients with severe or very severe aplastic anemia (SAA/VSAA) who failed to respond to immunosuppressive therapy (IST) at 3 months. Methods: We retrospectively analyzed the clinical data of 173 patients with SAA/VSAA from 2017 to 2018 who received IST and were classified as nonresponders at 3 months. Univariate and multivariate logistic regression analysis were used to evaluate factors that could predict the response at 6 months. Results: Univariate analysis showed that the 3-month hemoglobin (HGB) level (P=0.017) , platelet (PLT) level (P=0.005) , absolute reticulocyte count (ARC) (P<0.001) , trough cyclosporine concentration (CsA-C0) (P=0.042) , soluble transferrin receptor (sTfR) level (P=0.003) , improved value of reticulocyte count (ARC(△)) (P<0.001) , and improved value of soluble transferrin receptor (sTfR(△)) level (P<0.001) were related to the 6-month response. The results of the multivariate analysis showed that the PLT level (P=0.020) and ARC(△) (P<0.001) were independent prognostic factors for response at 6 months. If the ARC(△) was less than 6.9×10(9)/L, the 6-month hematological response rate was low, regardless of the patient's PLT count. Survival analysis showed that both the 3-year overall survival (OS) [ (80.1±3.9) % vs (97.6±2.6) %, P=0.002] and 3-year event-free survival (EFS) [ (31.4±4.5) % vs (86.5±5.3) %, P<0.001] of the nonresponders at 6 months were significantly lower than those of the response group. Conclusion: Residual hematopoietic indicators at 3 months after IST are prognostic parameters. The improved value of the reticulocyte count could reflect whether the bone marrow hematopoiesis is recovering and the degree of recovery. A second treatment could be performed sooner for patients with a very low ARC(△).

First-line Cemiplimab versus Standard Chemotherapy in Advanced Non-small Cell Lung Cancer Patients with at Least 50% Programmed Cell Death Receptor Ligand-1 Positivity: Analysis of Cost-effectiveness

AIMS

The EMPOWER-Lung 1 trial showed that cemiplimab significantly prolongs the duration of progression-free survival and overall survival in advanced non-small cell lung cancer (NSCLC) patients with at least 50% programmed cell death receptor ligand-1 (PD-L1) positivity, yet the financial burden may limit its use. The aim of the present study was to evaluate the cost-effectiveness of cemiplimab versus chemotherapy in a US setting.

MATERIALS AND METHODS

A Markov model, with three mutually exclusive health states, was used to compare the expected health outcomes and cost of cemiplimab with chemotherapy. Survival data and transition probabilities were collected from the EMPOWER-Lung 1 trial. Utility values and costs are publicly available from open sources. One-way and probabilistic sensitivity analyses were conducted in both the whole population and subgroups to test the robustness of the parameters and structure.

RESULTS

Treatment of NSCLC with cemiplimab yielded an extra 1.07 quality-adjusted life years (QALYs) at an additional cost of $98 211 compared with chemotherapy, associated with an incremental cost-effectiveness ratio of $91 891/QALY and an incremental net health benefit of 0.087 QALYs at a willingness to pay threshold of $100 000/QALY. The probabilistic sensitivity analysis indicated that cemiplimab provided an 83.2% probability of being cost-effective. One-way sensitivity analysis suggested that the price of cemiplimab was the chief driver in this model. A subgroup analysis showed that cemiplimab was the preferred incremental net health benefit in more than half of the subgroups, including patients with squamous type disease and metastases.

CONCLUSIONS

Cemiplimab is a cost-effective option in the first-line treatment of NSCLC in patients who are at least 50% PD-L1 positive from an American perspective.

miR-7 regulates the apoptosis of chicken primary myoblasts through the KLF4 gene

1. MicroRNAs (miRNAs) play a vital role in the proliferation, differentiation, and apoptosis of myoblasts. However, the effect of miR-7 on the apoptosis of chicken primary myoblasts (CPMs) and its mechanism is still unclear.2. In this study, the expression of apoptosis marker genes (RAF1, Caspase3, Caspase9, Cytc, Fas) in CPMs was significantly increased after transfection of miR-7 mimic. The expression of the apoptosis marker genes in CPMs was significantly reduced after transfection with miR-7 inhibitor. Flow cytometry showed that the late apoptosis rate of the mimic group was significantly higher than the negative control (NC). The viable cells of the mimic group were significantly lower than the NC. In contrast, inhibition of miR-7 had the opposite effect.3. The dual-luciferase assay showed that the KLF4 was a target gene of miR-7. The rescue experiment showed that the KLF4 gene could attenuate the effect of miR-7 on the expression of apoptosis marker genes in CPMs.4. Determination of the function the KLF4 gene showed that the expression of the apoptosis marker genes in CPMs decreased significantly compared with the NC after its overexpression. Inhibition of KLF4 gene had the opposite effect. Flow cytometry showed that overexpression of the KLF4 gene inhibited early apoptosis of myoblasts (P ≤ 0.01), while interference with the KLF4 gene could promote early apoptosis of myoblasts (P ≤ 0.001).5. The results demonstrated, for the first time, that miR-7 promotes apoptosis in chicken primary myoblasts by regulating the expression of the KLF4 gene.

Abstract 578: Comparative analysis of cell free DNA with whole-exome sequencing (cfWES) and application to personalized minimal residual disease (MRD) monitoring

Liquid biopsy has become increasingly important in cancer diagnosis, personalized medicine, and disease progression monitoring. Conventional liquid biopsy relies on cancer gene panels which often contain fewer than 500 genes. Despite the revolutionary impact it has brought to the cancer research and cancer patient care, gene panels often miss many key mutations involved in cancer development and drug response. To fully capture the genetic variations embedded in cfDNA, we have developed Predicine-cfWES assay, which expands the features of our existing 152-gene PredicineCARE and 600-gene PredicineATLAS NGS panel with additional coverage of coding regions of the entire human genome. With 2500 x sequencing depth, Predicine-cfWES assay detects common cancer variants at sensitivity of 1% allele frequency and precisely measures copy number variations, such as loss of tumor suppressor genes (PTEN, BRCA2, p53) and gain of oncogenic driver genes (AR, Myc, ERBB2). Variants detected by Predicine-cfWES assay was confirmed by PredicineCARE panel based NGS assay and further used in tumor-agnostic personalized MRD assay. In conclusion, we have developed a comprehensive liquid biopsy solution to profile cfDNA with broad coverage of ~20,000 genes in the whole exome and higher sensitivity in a focused set of clinically actionable cancer variants for more personalized MRD monitoring in cancer patients.

Citation Format: Amy Xiaohong Wang, Zhixin Zhao, Chao Dai, Kemin Zhou, Shidong Jia, Pan Du, Shujun Luo. Comparative analysis of cell free DNA with whole-exome sequencing (cfWES) and application to personalized minimal residual disease (MRD) monitoring [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 578.

Abstract 2242: Blood-based genome-wide copy number analysis of 500 cancer patients

Copy number variation (CNV) is an important characteristic in cancer genome. Blood-based low-pass whole genome sequencing (LP-WGS) has been increasingly used to identify copy number variations of large genomic ranges in cancer. Conventional LP-WGS data analysis lacks the identification of focal CNV of small genomic ranges and often includes biased estimation of copy-neutral baseline when unbalanced genome-wide copy number changes are present. In this study, we have developed a proprietary algorithm analysis pipeline and leverage PredicineCARE and PredicineATLAS panel-based sequencing platform to identify focal CNVs missed by LP-WGS, and accurately infer copy number neutral baseline for LP-WGS. Here we present plasma-based LP-WGS results from 500 cancer patients, including breast, prostate, pancreatic and lung cancers. Our study demonstrates a cancer type-specific pattern of copy number variation across chromosome arms. The CNV abnormality score we developed in this study can be used to distinguish healthy person from cancer patient, and monitor disease progression for longitudinal patient samples.

Citation Format: Chao Dai, Amy Xiaohong Wang, Zhixin Zhao, Feng Xie, Kemin Zhou, Shujun Luo, Shidong Jia, Pan Du. Blood-based genome-wide copy number analysis of 500 cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2242.

High-throughput sequencing reveals crucial miRNAs in skeletal muscle development of Bian chicken

1. Growth performance is significant for chickens. MicroRNAs (miRNAs) have been found to play important roles in the post-transcriptional regulation of skeletal muscle growth. However, the mechanism of miRNAs in this process has not been elucidated.2. This study involved collecting leg muscle from slow- and fast-growing groups of Bian chicken at 16 weeks of age for high-throughput sequencing. A total of 42 differentially expressed miRNAs (DEMs) were identified. Among them, 22 DEMs were up-regulated and 20 DEMs were down-regulated.3. Biological process terms, relating to growth, were found by GO enrichment for target genes of DEMs and KEGG pathway analysis of target genes. This revealed some significantly enriched pathways closely related to skeletal muscle development, such as the calcium signalling pathway, ECM-receptor interaction, lysine degradation, apoptosis and tight junctions. Network interaction analysis of DEMs and target genes showed that the top fifty hub genes were targeted by thirteen DEMs.4. Four important miRNAs (novel_miR_158, novel_miR_144, novel_miR_291, and miR-205a) as well as some other valuable miRNAs, such as gga-miR-214 and gga-miR-3525 were identified. The qPCR results of five DEMs were highly consistent with that of sequencing between the two groups, which proved the reliability of miRNA-seq.5. The study will help to improve the molecular mechanism of miRNAs in chickens and guide future experiments concerning miRNA function in chicken growth.

[A sub-cohort study design of the maternal and infant microbes in China National Birth Cohort]

The importance of gut microbes to human health has gradually attracted attention. With the use of animal models, it has been revealed that maternal microbes during pregnancy could influence their children's health outcomes through shaping their microbial composition and regulating the development of their metabolic and immune system. However, the physiological mechanism of the human body is more complex and is affected by the interaction of multiple factors. The research results obtained from animal models are often inconsistent with human studies. At present, the influence of maternal intestinal microbes during pregnancy on the microbial colonization in their offspring and on a series of children's health outcomes is still unclear. Establishing a sub-cohort to detect the microbiome of the women across pregnancy and of their offspring, and further to integrate with variety of environmental and behavioral exposures can better provide reliable support for the research on the mechanism of children's health and diseases. This paper briefly introduces the research objectives, content, progress, strength and limitations of the sub-cohort study.

[Quality control and measures of China National Birth Cohort]

Birth cohort is an effective method to explore the relationship between various prepregnant and pregnant exposures and the health of fetuses, infants and young children. It is a long construction period to build a birth cohort and the quality of research may be affected by many factors. This paper reviews the quality assurance and quality control measures in the process of China National Birth Cohort (CNBC), and summarizes the construction experience. We aim to provide experience for related cohort studies, which could improve the quality of cohort studies through removing the impact of related factors. CNBC adopted a series of measures to ensure the quality of research in the top-level design of quality assurance, including screening research center, developing member management system, formulating standard operating procedures and training staff by it. In terms of quality control, it includes real-time, timely and timing quality control for the process of data generation, full-cycle quality control for biological sample collection, processing, storage and comprehensive three-dimensional quality control for staff training, supervision and quantitative assessment.