Browsing by Author "Qu, Chunjing"

Now showing 1 - 3 of 3
  • Thumbnail Image
    Item
    Recapitulation of complex transport and action of drugs at tumor microenvironment using tumor-microenvironment-on-chip
    (Elsevier, 2016-09-28) Han, Bumsoo; Qu, Chunjing; Park, Kinam; Konieczny, Stephen F.; Korc, Murray; Medicine, School of Medicine
    Targeted delivery aims to selectively distribute drugs to targeted tumor tissue but not to healthy tissue. This can address many of clinical challenges by maximizing the efficacy but minimizing the toxicity of anti-cancer drugs. However, complex tumor microenvironment poses various barriers hindering the transport of drugs and drug delivery systems. New tumor models that allow for the systematic study of these complex environments are highly desired to provide reliable test beds to develop drug delivery systems for targeted delivery. Recently, research efforts have yielded new in vitro tumor models, the so called tumor-microenvironment-on-chip, that recapitulate certain characteristics of the tumor microenvironment. These new models show benefits over other conventional tumor models, and have the potential to accelerate drug discovery and enable precision medicines. However, further research is warranted to overcome their limitations and to properly interpret the data obtained from these models. In this article, key features of the in vivo tumor microenvironment that are relevant to drug transport processes for targeted delivery was discussed, and the current status and challenges for developing in vitro transport model systems was reviewed.
  • Thumbnail Image
    Item
    Reliable detection of subchromosomal deletions and duplications using cell-based noninvasive prenatal testing
    (Wiley, 2018-10-25) Vossaert, Liesbeth; Wang, Qun; Salman, Roseen; Zhuo, Xinming; Qu, Chunjing; Henke, David; Seubert, Ron; Chow, Jennifer; U'ren, Lance; Enright, Brennan; Stilwell, Jackie; Kaldjian, Eric; Yang, Yaping; Shaw, Chad; Levy, Brynn; Wapner, Ronald; Breman, Amy; Veyver, Ignatia Van den; Beaudet, Arthur; Medical and Molecular Genetics, School of Medicine
    Objective To gather additional data on the ability to detect subchromosomal abnormalities of various sizes in single fetal cells isolated from maternal blood, using low-coverage shotgun next-generation sequencing for cell-based noninvasive prenatal testing (NIPT). Method Fetal trophoblasts were recovered from approximately 30 mL of maternal blood using maternal white blood cell depletion, density-based cell separation, immunofluorescence staining, and high-resolution scanning. These trophoblastic cells were picked as single cells and underwent whole genome amplification for subsequent genome-wide copy number analysis and genotyping to confirm the fetal origin of the cells. Results Applying our fetal cell isolation method to a series of 125 maternal blood samples, we detected on average 4.17 putative fetal cells/sample. The series included 15 cases with clinically diagnosed fetal aneuploidies and five cases with subchromosomal abnormalities. This method was capable of detecting findings that were 1 to 2 Mb in size, and all were concordant with the microarray or karyotype data obtained on a fetal sample. A minority of fetal cells showed evidence of genome degradation likely related to apoptosis. Conclusion We demonstrate that this cell-based NIPT method has the capacity to reliably diagnose fetal chromosomal abnormalities down to 1 to 2 Mb in size.
  • Thumbnail Image
    Item
    Validation Studies for Single Circulating Trophoblast Genetic Testing as a Form of Noninvasive Prenatal Diagnosis
    (Elsevier, 2019-12-05) Vossaert, Liesbeth; Wang, Qun; Salman, Roseen; McCombs, Anne K.; Patel, Vipulkumar; Qu, Chunjing; Mancini, Michael A.; Edwards, Dean P.; Malovannaya, Anna; Liu, Pengfei; Shaw, Chad A.; Levy, Brynn; Wapner, Ronald J.; Bi, Weimin; Breman, Amy M.; Van den Veyver, Ignatia B.; Beaudet, Arthur L.; Medical and Molecular Genetics, School of Medicine
    It has long been appreciated that genetic analysis of fetal or trophoblast cells in maternal blood could revolutionize prenatal diagnosis. We implemented a protocol for single circulating trophoblast (SCT) testing using positive selection by magnetic-activated cell sorting and single-cell low-coverage whole-genome sequencing to detect fetal aneuploidies and copy-number variants (CNVs) at ∼1 Mb resolution. In 95 validation cases, we identified on average 0.20 putative trophoblasts/mL, of which 55% were of high quality and scorable for both aneuploidy and CNVs. We emphasize the importance of analyzing individual cells because some cells are apoptotic, in S-phase, or otherwise of poor quality. When two or more high-quality trophoblast cells were available for singleton pregnancies, there was complete concordance between all trophoblasts unless there was evidence of confined placental mosaicism. SCT results were highly concordant with available clinical data from chorionic villus sampling (CVS) or amniocentesis procedures. Although determining the exact sensitivity and specificity will require more data, this study further supports the potential for SCT testing to become a diagnostic prenatal test.