Lei Chang

Bio: Lei Chang is an academic researcher from Protein Sciences. The author has contributed to research in topics: Medicine & Proteome. The author has an hindex of 10, co-authored 32 publications receiving 221 citations.

Urine Proteome of COVID-19 Patients

Abstract: SUMMARY The atypical pneumonia (COVID-19) caused by SARS-CoV-2 is an ongoing pandemic and a serious threat to global public health. The COVID-19 patients with severe symptoms account for a majority of mortality of this disease. However, early detection and effective prediction of patients with mild to severe symptoms remains challenging. In this study, we performed proteomic profiling of urine samples from 32 healthy control individuals and 6 COVID-19 positive patients (3 mild and 3 severe). We found that urine proteome samples from the mild and severe COVID-19 patients with comorbidities can be clearly differentiated from healthy proteome samples based on the clustering analysis. Multiple pathways have been compromised after the COVID-19 infection, including the dysregulation of immune response, complement activation, platelet degranulation, lipoprotein metabolic process and response to hypoxia. We further validated our finding by directly comparing the same patients’ urine proteome after recovery. This study demonstrates the COVID-19 pathophysiology related molecular alterations could be detected in the urine and the potential application of urinary proteome in auxiliary diagnosis, severity determination and therapy development of COVID-19.

Proteomic Analysis and NIR-II Imaging of MCM2 Protein in Hepatocellular Carcinoma

Abstract: Targeted therapy of hepatocellular carcinoma (HCC) is essential for improved therapies. Therefore, identification of key targets specifically to HCC is an urgent requirement. Herein, an iTRAQ quantitative proteomic approach was employed to identify differentially expressed proteins in HCC tumor tissues. Of the upregulated tumor-related proteins, minichromosome maintenance 2 (MCM2), a DNA replication licensing factor, was one of the most significantly altered proteins, and its overexpression was confirmed using tissue microarray. Clinicopathological analysis of multiple cohorts of HCC patients indicated that overexpression of MCM2 was validated in 89.8% tumor tissues and strongly correlated with clinical stage. Furthermore, siRNA-mediated repression of MCM2 expression resulted in significant suppression of the HepG2 cell cycle and proliferation through the cyclin D-dependent kinases (CDKs) 2/7 pathway. Finally, the first small molecule-based MCM2-targeted NIR-II probe CH1055-MCM2 was concisely generated an...

Hepatitis B virus X induces inflammation and cancer in mice liver through dysregulation of cytoskeletal remodeling and lipid metabolism.

Abstract: // Zhongwei Xu 1, 7 , Linghui Zhai 1 , Tailong Yi 1, 4 , Huiying Gao 1 , Fengxu Fan 1, 4 , Yanchang Li 1 , Youliang Wang 2 , Ning Li 1 , Xiaohua Xing 1 , Na Su 1 , Feilin Wu 1 , Lei Chang 1 , Xiuli Chen 6 , Erhei Dai 6 , Chao Zhao 5 , Xiao Yang 2 , Chunping Cui 1 , Ping Xu 1, 3, 4 1 State Key Laboratory of Proteomics, Beijing Proteome Research Center, National Engineering Research Center for Protein Drugs, National Center for Protein Sciences Beijing, Institute of Radiation Medicine, Beijing, 102206, P.R. China 2 Beijing Institute of Bioengineering, Beijing, 100071, P. R. China 3 Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education and Wuhan University School of Pharmaceutical Sciences, Wuhan, 430072, P. R. China 4 Anhui Medical University, Hefei, 230032, China 5 Key Laboratory of Medical Molecular Virology, School of Basic Medical Sciences, and Research Center on Aging and Medicine, Fudan University, Shanghai, 200032, China 6 The Fifth Hospital of Shijiazhuang City, Shijiazhuang, 050021, China 7 Central Laboratory, Logistics University of Chinese People’s Armed Police Force, Tianjin, 300309, China Correspondence to: Ping Xu, email: xuping@mail.ncpsb.org Keywords: HBx, SILAM, CDC42, CFL1, ADFP Received: March 10, 2016 Accepted: September 13, 2016 Published: September 30, 2016 ABSTRACT Hepatitis B virus X protein (HBx) participates in the occurrence and development processes of hepatocellular carcinoma (HCC) as a multifunctional regulation factor. However, the underlying molecular mechanism remains obscure. Here, we describe the use of p21 HBx/+ mouse and SILAM (Stable Isotope Labeling in Mammals) strategy to define the pathological mechanisms for the occurrence and development of HBx induced liver cancer. We systematically compared a series of proteome samples from regular mice, 12- and 24-month old p21 HBx/+ mice representing the inflammation and HCC stages of liver disease respectively and their nontransgenic wild-type (WT) littermates. Totally we identified 22 and 97 differentially expressed proteins out of a total of 2473 quantified proteins. Bioinformatics analysis suggested that the lipid metabolism and CDC42-induced cytoskeleton remodeling pathways were strongly activated by the HBx transgene. Interestingly, the protein-protein interaction MS study revealed that HBx directly interacted with multiple proteins in these two pathways. The same effect of up-regulation of cytoskeleton and lipid metabolism related proteins, including CDC42, CFL1, PPARγ and ADFP, was also observed in the Huh-7 cells transfected with HBx. More importantly, CFL1 and ADFP were specifically accumulated in HBV-associated HCC (HBV-HCC) patient samples, and their expression levels were positively correlated with the severity of HBV-related liver disease. These results provide evidence that HBx induces the dysregulation of cytoskeleton remodeling and lipid metabolism and leads to the occurrence and development of liver cancer. The CFL1 and ADFP might be served as potential biomarkers for prognosis and diagnosis of HBV-HCC.

ROS and the DNA damage response in cancer.

Abstract: Reactive oxygen species (ROS) are a group of short-lived, highly reactive, oxygen-containing molecules that can induce DNA damage and affect the DNA damage response (DDR). There is unequivocal pre-clinical and clinical evidence that ROS influence the genotoxic stress caused by chemotherapeutics agents and ionizing radiation. Recent studies have provided mechanistic insight into how ROS can also influence the cellular response to DNA damage caused by genotoxic therapy, especially in the context of Double Strand Breaks (DSBs). This has led to the clinical evaluation of agents modulating ROS in combination with genotoxic therapy for cancer, with mixed success so far. These studies point to context dependent outcomes with ROS modulator combinations with Chemotherapy and radiotherapy, indicating a need for additional pre-clinical research in the field. In this review, we discuss the current knowledge on the effect of ROS in the DNA damage response, and its clinical relevance.

The complement system in COVID-19: friend and foe?

Abstract: Coronavirus disease 2019 (COVID-19), the disease caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has resulted in a global pandemic and a disruptive health crisis. COVID-19-related morbidity and mortality have been attributed to an exaggerated immune response. The role of complement activation and its contribution to illness severity is being increasingly recognized. Here, we summarize current knowledge about the interaction of coronaviruses with the complement system. We posit that (a) coronaviruses activate multiple complement pathways; (b) severe COVID-19 clinical features often resemble complementopathies; (c) the combined effects of complement activation, dysregulated neutrophilia, endothelial injury, and hypercoagulability appear to be intertwined to drive the severe features of COVID-19; (d) a subset of patients with COVID-19 may have a genetic predisposition associated with complement dysregulation; and (e) these observations create a basis for clinical trials of complement inhibitors in life-threatening illness.

Novel near-infrared II aggregation-induced emission dots for in vivo bioimaging

Abstract: Near-infrared II fluorescence imaging holds great promise for in vivo imaging and imaging-guided surgery with deep penetration and high spatiotemporal resolution. However, most NIR-II aromatic luminophores suffer from the notorious aggregation-caused quenching (ACQ) effect in the aqueous solution, which largely hinders their biomedical application in vivo. In this study, the first NIR-II organic aggregation-induced emission (AIE) fluorophore (HLZ-BTED), encapsulated as nanoparticles (HLZ-BTED dots) for in vivo biomedical imaging, was designed and synthesized. The NIR-II AIE HLZ-BTED dots showed high temporal resolution, high photostability, outstanding water-solubility and biocompatibility in vitro and in vivo. The HLZ-BTED dots were further used for long-term breast tumor imaging and visualizing tumor-feeding blood vessels, long-term hind limb vasculature and incomplete hind limb ischemia. More importantly, as a proof-of-concept, this is the first time that non-invasive and real-time NIR-II imaging of the gastrointestinal tract in health and disease has been performed, making the AIE dots a promising tool for gastrointestinal (GI) tract research, such as understanding the healthy status of GI peristalsis, diagnosing and evaluating intestinal motility dysfunction, and assessing drug effects on intestinal obstruction.

Upconversion NIR-II fluorophores for mitochondria-targeted cancer imaging and photothermal therapy.

Abstract: NIR-II fluorophores have shown great promise for biomedical applications with superior in vivo optical properties. To date, few small-molecule NIR-II fluorophores have been discovered with donor-acceptor-donor (D-A-D) or symmetrical structures, and upconversion-mitochondria-targeted NIR-II dyes have not been reported. Herein, we report development of D-A type thiopyrylium-based NIR-II fluorophores with frequency upconversion luminescence (FUCL) at ~580 nm upon excitation at ~850 nm. H4-PEG-PT can not only quickly and effectively image mitochondria in live or fixed osteosarcoma cells with subcellular resolution at 1 nM, but also efficiently convert optical energy into heat, achieving mitochondria-targeted photothermal cancer therapy without ROS effects. H4-PEG-PT has been further evaluated in vivo and exhibited strong tumor uptake, specific NIR-II signals with high spatial and temporal resolution, and remarkable NIR-II image-guided photothermal therapy. This report presents the first D-A type thiopyrylium NIR-II theranostics for synchronous upconversion-mitochondria-targeted cell imaging, in vivo NIR-II osteosarcoma imaging and excellent photothermal efficiency. Currently available mitochondria-targeted fluorescent dyes emit only one color in the visible or NIR-I and their applications are limited. Here, the authors develop upconversion mitochondria-targeted NIR-II fluorophores for synchronous upconversion-mitochondria-targeted cell imaging, in vivo NIR-II osteosarcoma imaging and photothermal efficiency

Polymethine Thiopyrylium Fluorophores with Absorption beyond 1000 nm for Biological Imaging in the Second Near-Infrared Subwindow

Abstract: Small-molecule fluorescence imaging in the second near-infrared (NIR-II, 1000–1700 nm) window has gained increasing interest in clinical application. Till now, very few studies have been exploited in the small-molecule fluorophores with both excitation and emission in the NIR-II window. Inspired by the indocyanine green structure, a series of polymethine dyes with both absorption and emission in the NIR-II window have been developed for NIR-II imaging, providing the feasibility to directly compare optical imaging in the NIR-IIa (1300–1400 nm) subwindow under 1064 nm excitation with that in the NIR-II window under 808 nm excitation. The signal–background ratio and the tumor–normal tissue ratio achieved great improvement under 1064 nm excitation in the imaging of mouse blood pool and U87 glioma tumors. Our study not only introduces a broadband emission fluorophore for both NIR-II and NIR-IIa imaging, but also reveals the advantages of NIR-II excitation over NIR-I in in vivo imaging.