1
|
Abd El-Karim SS, Syam YM, El Kerdawy AM, Abdel-Mohsen HT. Rational design and synthesis of novel quinazolinone N-acetohydrazides as type II multi-kinase inhibitors and potential anticancer agents. Bioorg Chem 2024; 142:106920. [PMID: 37898082 DOI: 10.1016/j.bioorg.2023.106920] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Revised: 10/10/2023] [Accepted: 10/14/2023] [Indexed: 10/30/2023]
Abstract
In the current investigation, a new class of quinazolinone N-acetohydrazides 9a-v was designed as type II multi-kinase inhibitors. The target quinazolinones were tailored so that the quinazolinone moiety would occupy the front pocket of the binding sites of VEGFR-2, FGFR-1 and BRAF kinases, meanwhile, the phenyl group at position 2 would act as a spacer which was functionalized at position 4 with an N-acetohydrazide linker that could achieve the key interactions with the essential gate area amino acids. The hydrazide moiety was linked to diverse aryl derivatives to occupy the hydrophobic back pocket of the DFG-out conformation of target kinases. The synthesized quinazolinone derivatives 9a-v demonstrated moderate to potent VEGFR-2 inhibitory activity with IC50 spanning from 0.29 to 5.17 µM. Further evaluation of the most potent derivatives on FGFR-1, BRAFWT and BRAFV600E showed that the quinazolinone N-acetohydrazides 9d, 9e, 9f, 9l and 9m have a potent multi-kinase inhibitory activity. Concurrently, 9b, 9d, 9e, 9k, 9l, 9o, 9q demonstrated potent growth inhibitory activity on NCI cancer cell lines with GI50 reaching 0.72 µM. In addition, compound 9e arrested the cell cycle progression in MDA-MB-231 cell line at the G2/M phase and showed the ability to induce apoptosis.
Collapse
Affiliation(s)
- Somaia S Abd El-Karim
- Department of Therapeutic Chemistry, Pharmaceutical and Drug Industries Research Institute, National Research Centre, P. O. Box 12622 El-Bohouth Street, Dokki, Cairo, Egypt
| | - Yasmin M Syam
- Department of Therapeutic Chemistry, Pharmaceutical and Drug Industries Research Institute, National Research Centre, P. O. Box 12622 El-Bohouth Street, Dokki, Cairo, Egypt
| | - Ahmed M El Kerdawy
- School of Pharmacy, College of Health and Science, University of Lincoln, Joseph Banks Laboratories, Green Lane, Lincoln, Lincolnshire, United Kingdom; Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Cairo University, Kasr El-Aini Street, P.O. Box 11562, Cairo, Egypt
| | - Heba T Abdel-Mohsen
- Chemistry of Natural and Microbial Products Department, Pharmaceutical and Drug Industries Research Institute, National Research Centre, P. O. Box 12622 El-Bohouth Street, Dokki, Cairo, Egypt.
| |
Collapse
|
2
|
Exploring the Past, Present, and Future of Anti-Angiogenic Therapy in Glioblastoma. Cancers (Basel) 2023; 15:cancers15030830. [PMID: 36765787 PMCID: PMC9913517 DOI: 10.3390/cancers15030830] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 01/25/2023] [Accepted: 01/26/2023] [Indexed: 01/31/2023] Open
Abstract
Glioblastoma, a WHO grade IV astrocytoma, constitutes approximately half of malignant tumors of the central nervous system. Despite technological advancements and aggressive multimodal treatment, prognosis remains dismal. The highly vascularized nature of glioblastoma enables the tumor cells to grow and invade the surrounding tissue, and vascular endothelial growth factor-A (VEGF-A) is a critical mediator of this process. Therefore, over the past decade, angiogenesis, and more specifically, the VEGF signaling pathway, has emerged as a therapeutic target for glioblastoma therapy. This led to the FDA approval of bevacizumab, a monoclonal antibody designed against VEGF-A, for treatment of recurrent glioblastoma. Despite the promising preclinical data and its theoretical effectiveness, bevacizumab has failed to improve patients' overall survival. Furthermore, several other anti-angiogenic agents that target the VEGF signaling pathway have also not demonstrated survival improvement. This suggests the presence of other compensatory angiogenic signaling pathways that surpass the anti-angiogenic effects of these agents and facilitate vascularization despite ongoing VEGF signaling inhibition. Herein, we review the current state of anti-angiogenic agents, discuss potential mechanisms of anti-angiogenic resistance, and suggest potential avenues to increase the efficacy of this therapeutic approach.
Collapse
|
3
|
Liang Q, Peng J, Xu Z, Li Z, Jiang F, Ouyang L, Wu S, Fu C, Liu Y, Liu Y, Yan Y. Pan-cancer analysis of the prognosis and immunological role of AKAP12: A potential biomarker for resistance to anti-VEGF inhibitors. Front Genet 2022; 13:943006. [PMID: 36110213 PMCID: PMC9468827 DOI: 10.3389/fgene.2022.943006] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 08/01/2022] [Indexed: 11/13/2022] Open
Abstract
The primary or acquired resistance to anti-VEGF inhibitors remains a common problem in cancer treatment. Therefore, identifying potential biomarkers enables a better understanding of the precise mechanism. Through the GEO database, three profiles associated with bevacizumab (BV) resistance to ovarian cancer, glioma, and non-small-cell lung carcinoma, respectively, were collected for the screening process, and two genes were found. A-kinase anchor protein 12 (AKAP12), one of these two genes, correlates with tumorigenesis of some cancers. However, the role of AKAP12 in pan-cancer remains poorly defined. The present study first systematically analyzed the association of AKAP12 with anti-VEGF inhibitors’ sensitivity, clinical prognosis, DNA methylation, protein phosphorylation, and immune cell infiltration across various cancers via bioinformatic tools. We found that AKAP12 was upregulated in anti-VEGF therapy-resistant cancers, including ovarian cancer (OV), glioblastoma (GBM), lung cancer, and colorectal cancer (CRC). A high AKAP12 expression revealed dismal prognoses in OV, GBM, and CRC patients receiving anti-VEGF inhibitors. Moreover, AKAP12 expression was negatively correlated with cancer sensitivity towards anti-VEGF therapy. Clinical prognosis analysis showed that AKAP12 expression predicted worse prognoses of various cancer types encompassing colon adenocarcinoma (COAD), OV, GBM, and lung squamous cell carcinoma (LUSC). Gene mutation status may be a critical cause for the involvement of AKAP12 in resistance. Furthermore, lower expression of AKAP12 was detected in nearly all cancer types, and hypermethylation may explain its decreased expression. A decreased phosphorylation of T1760 was observed in breast cancer, clear-cell renal cell carcinoma, and lung adenocarcinoma. For the immunologic significance, AKAP12 was positively related to the abundance of pro-tumor cancer-associated fibroblasts (CAFs) in various types of cancer. The results of Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis suggested that “cell junction organization” and “MAPK pathway” participated in the effect of AKAP12. Importantly, we discovered that AKAP12 expression was greatly associated with metastasis of lung adenocarcinoma as well as differential and angiogenesis of retinoblastoma through investigating the single-cell sequencing data. Our study showed that the dual role of AKAP12 in various cancers and AKAP12 could serve as a biomarker of anti-VEGF resistance in OV, GBM, LUSC, and COAD.
Collapse
Affiliation(s)
- Qiuju Liang
- Department of Pharmacy, Xiangya Hospital, Central South University, Changsha, China
- National Clinical Research Center for Geriatric Disorders, Institute for Rational and Safe Medication Practices, Xiangya Hospital, Central South University, Changsha, China
| | - Jinwu Peng
- Department of Pathology, Xiangya Hospital, Central South University, Changsha, China
- Department of Pathology, Xiangya Changde Hospital, Changde, China
| | - Zhijie Xu
- Department of Pathology, Xiangya Hospital, Central South University, Changsha, China
| | - Zhilan Li
- Department of Pathology, Xiangya Changde Hospital, Changde, China
| | - Feng Jiang
- Department of Pathology, Xiangya Changde Hospital, Changde, China
| | - Lingzi Ouyang
- Department of Pathology, Xiangya Changde Hospital, Changde, China
| | - Shangjun Wu
- Department of Pathology, Xiangya Changde Hospital, Changde, China
| | - Chencheng Fu
- Department of Pathology, Xiangya Changde Hospital, Changde, China
| | - Ying Liu
- Department of Pathology, Xiangya Changde Hospital, Changde, China
| | - Yuanhong Liu
- Department of Pharmacy, Xiangya Hospital, Central South University, Changsha, China
- National Clinical Research Center for Geriatric Disorders, Institute for Rational and Safe Medication Practices, Xiangya Hospital, Central South University, Changsha, China
| | - Yuanliang Yan
- Department of Pharmacy, Xiangya Hospital, Central South University, Changsha, China
- National Clinical Research Center for Geriatric Disorders, Institute for Rational and Safe Medication Practices, Xiangya Hospital, Central South University, Changsha, China
- *Correspondence: Yuanliang Yan,
| |
Collapse
|
4
|
Upadhyay N, Tilekar K, Safuan S, Kumar AP, Stalin J, Ruegg C, Ramaa C S. Recent Anti‐angiogenic Drug Discovery Efforts To Combat Cancer. ChemistrySelect 2021. [DOI: 10.1002/slct.202101792] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Neha Upadhyay
- Department of Pharmaceutical Chemistry Bharati Vidyapeeth's College of Pharmacy Sector 8, CBD Belapur Navi Mumbai 400614 India
| | - Kalpana Tilekar
- Department of Pharmaceutical Chemistry Bharati Vidyapeeth's College of Pharmacy Sector 8, CBD Belapur Navi Mumbai 400614 India
| | - Sabreena Safuan
- Pusat pengajian sains School of Health Sciences Universiti Sains Malaysia Malaysia 16150 Kubang Kerian Kelantan
| | - Alan P. Kumar
- Department of Pharmacology National University of Singapore Singapore
| | - Jimmy Stalin
- Department of Oncology Microbiology, and Immunology University of Fribourg Chemin du Musée 18, PER17, CH 1700 Fribourg Switzerland
| | - Curzio Ruegg
- Department of Oncology Microbiology, and Immunology University of Fribourg Chemin du Musée 18, PER17, CH 1700 Fribourg Switzerland
| | - Ramaa C S
- Department of Pharmaceutical Chemistry Bharati Vidyapeeth's College of Pharmacy Sector 8, CBD Belapur Navi Mumbai 400614 India
| |
Collapse
|
5
|
Tian Z, Niu X, Yao W. Receptor Tyrosine Kinases in Osteosarcoma Treatment: Which Is the Key Target? Front Oncol 2020; 10:1642. [PMID: 32984034 PMCID: PMC7485562 DOI: 10.3389/fonc.2020.01642] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Accepted: 07/27/2020] [Indexed: 12/12/2022] Open
Abstract
Recent clinical trials have shown several multi-target tyrosine kinase inhibitors (TKIs) to be effective in the treatment of osteosarcoma. However, these TKIs have a number of targets, and it is yet unclear which of these targets has a key role in osteosarcoma treatment. In this review, we first summarize the TKIs that were studied in clinical trials registered on ClinicalTrials.gov. Further, we compare and discuss the targets of these TKIs. We found that TKIs with promising therapeutic effect for osteosarcoma include apatinib, cabozantinib, lenvatinib, regorafenib, and sorafenib. The key targets for osteosarcoma treatment may include VEGFRs and RET. The receptor tyrosine kinases (RTKs) MET, IGF-1R, AXL, PDGFRs, KIT, and FGFRs might be relevant but unimportant targets for osteosarcoma treatment. Inhibition of one type of RTK for the treatment of osteosarcoma is not effective. It is necessary to inhibit several relevant RTKs simultaneously to achieve a breakthrough in osteosarcoma treatment. This review provides comprehensive information on TKI targets relevant in osteosarcoma treatment, and it will be useful for further research in this field.
Collapse
Affiliation(s)
- Zhichao Tian
- Department of Orthopedics, The Affiliated Cancer Hospital of Zhengzhou University, Henan Cancer Hospital, Zhengzhou, China
| | - Xiaohui Niu
- Department of Orthopedic Oncology, Beijing Jishuitan Hospital, Beijing, China
| | - Weitao Yao
- Department of Orthopedics, The Affiliated Cancer Hospital of Zhengzhou University, Henan Cancer Hospital, Zhengzhou, China
| |
Collapse
|
6
|
Orbegoso C, Marquina G, George A, Banerjee S. The role of Cediranib in ovarian cancer. Expert Opin Pharmacother 2017; 18:1637-1648. [DOI: 10.1080/14656566.2017.1383384] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Cecilia Orbegoso
- Gynaecology Unit, Royal Marsden NHS Foundation Trust, London, UK
| | - Gloria Marquina
- Gynaecology Unit, Royal Marsden NHS Foundation Trust, London, UK
| | - Angela George
- Gynaecology Unit, Royal Marsden NHS Foundation Trust, London, UK
| | - Susana Banerjee
- Gynaecology Unit, Royal Marsden NHS Foundation Trust, London, UK
- Division of Clinical Studies, The Institiute of Cancer Research, London, UK
| |
Collapse
|
7
|
Jiang W, Liu P, Li X, Wang P. Identification of target genes of cediranib in alveolar soft part sarcoma using a gene microarray. Oncol Lett 2017; 13:2623-2630. [PMID: 28454442 PMCID: PMC5403492 DOI: 10.3892/ol.2017.5779] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Accepted: 01/04/2017] [Indexed: 11/06/2022] Open
Abstract
The aim of the present study was to identify the target genes of cediranib and the associated signaling pathways in alveolar soft part sarcoma (ASPS). A microarray dataset (GSE32569) was obtained from the Gene Expression Omnibus database. The R software package was used for data normalization and screening of differentially expressed genes (DEGs). The Database for Annotation, Visualization and Integrated Discovery was used to perform Gene Ontology analysis. Gene Set Enrichment Analysis was performed to obtain the up- and downregulated pathways in ASPS. The Distant Regulatory Elements of co-regulated genes database was used to identify the transcription factors (TFs) that were enriched in the signaling pathways. A protein-protein interaction (PPI) network was constructed using the Search Tool for the Retrieval of Interacting Genes/Proteins database and was visualized using Cytoscape software. A total of 71 DEGs, including 59 upregulated genes and 12 downregulated genes, were identified. Gene sets associated with ASPS were enriched primarily in four signaling pathways: The phenylalanine metabolism pathway, the mitogen-activated protein kinase (MAPK) signaling pathway, the taste transduction pathway and the intestinal immune network for the production of immunoglobulin A. Furthermore, 107 TFs were identified to be enriched in the MAPK signaling pathway. Certain genes, including those coding for Fms-like tyrosine kinase 1, kinase insert domain receptor, E-selectin and platelet-derived growth factor receptor D, that were associated with other genes in the PPI network, were identified. The present study identified certain potential target genes and the associated signaling pathways of cediranib action in ASPS, which may be helpful in understanding the efficacy of cediranib and the development of new targets for cediranib.
Collapse
Affiliation(s)
- Wenhua Jiang
- Department of Radiotherapy, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin's Clinical Research Center for Cancer, Sino-US Center of Lymphoma and Leukemia, Tianjin 300060, P.R. China.,Department of Radiotherapy, Second Hospital of Tianjin Medical University, Tianjin 300211, P.R. China
| | - Pengfei Liu
- Department of Lymphoma, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin's Clinical Research Center for Cancer, Sino-US Center of Lymphoma and Leukemia, Tianjin 300060, P.R. China
| | - Xiaodong Li
- Department of Radiotherapy, Second Hospital of Tianjin Medical University, Tianjin 300211, P.R. China
| | - Ping Wang
- Department of Radiotherapy, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin's Clinical Research Center for Cancer, Sino-US Center of Lymphoma and Leukemia, Tianjin 300060, P.R. China
| |
Collapse
|
8
|
Ntanasis-Stathopoulos I, Fotopoulos G, Tzanninis IG, Kotteas EA. The Emerging Role of Tyrosine Kinase Inhibitors in Ovarian Cancer Treatment: A Systematic Review. Cancer Invest 2016; 34:313-39. [PMID: 27486869 DOI: 10.1080/07357907.2016.1206117] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The present systematic review summarizes current evidence regarding the mechanisms of action, the efficacy, and the adverse effects of tyrosine kinase inhibitors (TKIs) in ovarian cancer patients. Phase II and III clinical trials were sought in the PubMed database and in the Clinical Trials.gov registry through September 30, 2015. Seventy-five clinical trials regarding TKIs targeting mainly vascular endothelial growth factor receptor, epidermal growth factor receptor, platelet-derived growth factor receptor, and sarcoma tyrosine kinase (Src) were yielded. The most promising results were noted with cediranib, nintedanib, and pazopanib. However, drawing universal conclusions about the potential integration of TKIs in ovarian cancer therapy remains elusive. Furthermore, emerging challenges and directions for the future research are critically discussed.
Collapse
Affiliation(s)
| | - George Fotopoulos
- a Oncology Unit, Sotiria General Hospital , Athens School of Medicine , Athens , Greece
| | | | - Elias A Kotteas
- a Oncology Unit, Sotiria General Hospital , Athens School of Medicine , Athens , Greece
| |
Collapse
|
9
|
Cranmer LD, Loggers ET, Pollack SM. Pazopanib in the management of advanced soft tissue sarcomas. Ther Clin Risk Manag 2016; 12:941-55. [PMID: 27354810 PMCID: PMC4907704 DOI: 10.2147/tcrm.s84792] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Therapy of soft tissue sarcomas represents an area of significant unmet need in oncology. Angiogenesis has been explored as a potential target both preclinically and clinically, with suggestions of activity. Pazopanib is a multitargeted tyrosine kinase inhibitor with prominent antiangiogenic effects. In a Phase II study, pazopanib demonstrated activity in strata enrolling patients with leiomyosarcomas, synovial sarcomas, or other sarcomas but not those enrolling adipocytic sarcomas. PALETTE, the pivotal Phase III trial, demonstrated improved progression-free survival versus placebo in pazopanib-treated patients previously treated for advanced soft tissue sarcomas. No survival benefit was observed, and adipocytic sarcomas were excluded. Health-related quality-of-life assessments indicated significant decrements in several areas affected by pazopanib toxicities, but no global deterioration. Cost-effectiveness analyses indicate that pazopanib therapy may or may not be cost-effective in different geographic settings. Pazopanib provides important proof-of-concept for antiangiogenic therapy in soft tissue sarcomas. Its use can be improved by further biological studies of its activity profile in sarcomas, studies of biological rational combinations, and clinicopathologic/biological correlative studies of activity to allow better drug targeting.
Collapse
Affiliation(s)
- Lee D Cranmer
- Division of Medical Oncology, University of Washington, Seattle, WA, USA
| | - Elizabeth T Loggers
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Seth M Pollack
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| |
Collapse
|
10
|
A phase I trial and PK study of cediranib (AZD2171), an orally bioavailable pan-VEGFR inhibitor, in children with recurrent or refractory primary CNS tumors. Childs Nerv Syst 2015; 31:1433-45. [PMID: 26188774 PMCID: PMC4561207 DOI: 10.1007/s00381-015-2812-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Accepted: 07/03/2015] [Indexed: 01/01/2023]
Abstract
BACKGROUND Cediranib (AZD2171), an oral pan-vascular endothelial growth factor (VEGF) inhibitor, was evaluated in this phase I study to determine its toxicity profile, dose-limiting toxicities (DLTs), maximum-tolerated dose (MTD), pharmacokinetics, and pharmacodynamics in children and adolescents with recurrent or refractory primary central nervous system (CNS) tumors. METHODS Children and adolescents <22 years were enrolled into one of two strata: stratum I—those not receiving enzyme-inducing anticonvulsant drugs (EIACD) and stratum II—those receiving EIACDs. Dose-level selection was based on the continual reassessment method (CRM). RESULTS Thirty-six eligible patients with median age of 12.7 years (range, 5.4-21.7 years) in stratum I (24 males) and 12 patients (7 males) in stratum II with median age of 13.4 years (range, 8.9-19.5 years) were initially assessed over a 4-week DLT evaluation period, modified to 6 weeks during the study. An MTD of 32 mg/m(2)/day was declared; however, excessive toxicities (transaminitis, proteinuria, diarrhea, hemorrhage, palmer-planter syndrome, reversible posterior leukoencephalopathy) in the expansion cohort treated at this dose suggested that it might not be tolerated over a longer time period. An expansion cohort at 20 mg/m(2)/day also demonstrated poor longer-term tolerability. Diffusion and perfusion MRI and PET imaging variables as well as biomarker analysis were performed and correlated with outcome. At 20 mg/m(2)/day, the median plasma area under the concentration-time curve at steady state was lower than that observed in adults at similar dosages. CONCLUSIONS While the MTD of once daily oral cediranib in children with recurrent or progressive CNS tumors was initially defined as 32 mg/m(2)/day, this dose and 20 mg/m(2)/day were not considered tolerable over a protracted time period.
Collapse
|
11
|
Hirte H, Lheureux S, Fleming G, Sugimoto A, Morgan R, Biagi J, Wang L, McGill S, Ivy S, Oza A. A phase 2 study of cediranib in recurrent or persistent ovarian, peritoneal or fallopian tube cancer: A trial of the Princess Margaret, Chicago and California Phase II Consortia. Gynecol Oncol 2015; 138:55-61. [DOI: 10.1016/j.ygyno.2015.04.009] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Accepted: 04/10/2015] [Indexed: 12/27/2022]
|
12
|
Zhao Y, Adjei AA. Targeting Angiogenesis in Cancer Therapy: Moving Beyond Vascular Endothelial Growth Factor. Oncologist 2015; 20:660-73. [PMID: 26001391 DOI: 10.1634/theoncologist.2014-0465] [Citation(s) in RCA: 390] [Impact Index Per Article: 43.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Accepted: 03/06/2015] [Indexed: 12/22/2022] Open
Abstract
UNLABELLED Angiogenesis, or the formation of new capillary blood vessels, occurs primarily during human development and reproduction; however, aberrant regulation of angiogenesis is also a fundamental process found in several pathologic conditions, including cancer. As a process required for invasion and metastasis, tumor angiogenesis constitutes an important point of control of cancer progression. Although not yet completely understood, the complex process of tumor angiogenesis involves highly regulated orchestration of multiple signaling pathways. The proangiogenic signaling molecule vascular endothelial growth factor (VEGF) and its cognate receptor (VEGF receptor 2 [VEGFR-2]) play a central role in angiogenesis and often are highly expressed in human cancers, and initial clinical efforts to develop antiangiogenic treatments focused largely on inhibiting VEGF/VEGFR signaling. Such approaches, however, often lead to transient responses and further disease progression because angiogenesis is regulated by multiple pathways that are able to compensate for each other when single pathways are inhibited. The platelet-derived growth factor (PDGF) and PDGF receptor (PDGFR) and fibroblast growth factor (FGF) and FGF receptor (FGFR) pathways, for example, provide potential escape mechanisms from anti-VEGF/VEGFR therapy that could facilitate resumption of tumor growth. Accordingly, more recent treatments have focused on inhibiting multiple signaling pathways simultaneously. This comprehensive review discusses the limitations of inhibiting VEGF signaling alone as an antiangiogenic strategy, the importance of other angiogenic pathways including PDGF/PDGFR and FGF/FGFR, and the novel current and emerging agents that target multiple angiogenic pathways for the treatment of advanced solid tumors. IMPLICATIONS FOR PRACTICE Significant advances in cancer treatment have been achieved with the development of antiangiogenic agents, the majority of which have focused on inhibition of the vascular endothelial growth factor (VEGF) pathway. VEGF targeting alone, however, has not proven to be as efficacious as originally hoped, and it is increasingly clear that there are many interconnected and compensatory pathways that can overcome VEGF-targeted inhibition of angiogenesis. Maximizing the potential of antiangiogenic therapy is likely to require a broader therapeutic approach using a new generation of multitargeted antiangiogenic agents.
Collapse
Affiliation(s)
- Yujie Zhao
- Roswell Park Cancer Institute, Buffalo, New York, USA
| | - Alex A Adjei
- Roswell Park Cancer Institute, Buffalo, New York, USA
| |
Collapse
|
13
|
Yang X, Shen F, Hu W, Coleman RL, Sood AK. New ways to successfully target tumor vasculature in ovarian cancer. Curr Opin Obstet Gynecol 2015; 27:58-65. [PMID: 25502429 PMCID: PMC4529067 DOI: 10.1097/gco.0000000000000136] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
PURPOSE OF REVIEW The aim of this article was to review the recent literature on potential therapeutic strategies for overcoming resistance to antivascular endothelial growth factor drugs in ovarian cancer. RECENT FINDINGS Although clinical benefits of antivascular endothelial growth factor therapy were observed in ovarian cancer treatment trials, this use yielded only modest improvement in progression-free survival and, with the exception of cediranib, no effect on overall survival. Adaptive resistance and escape from antiangiogenesis therapy is likely a multifactorial process, including induction of hypoxia, vascular modulators, and immune response. New drugs targeting the tumor vasculature or other components of the surrounding microenvironment have shown promising results. SUMMARY When to start and end antiangiogenesis therapy and the choice of optimal treatment combinations remain controversial. Further evaluation of personalized novel angiogenesis-based therapy is warranted. Defining the critical interaction of these agents and pathways and the appropriate predictive markers will become an increasingly important objective for effective treatment.
Collapse
Affiliation(s)
- Xiaoyun Yang
- Department of Gynecologic Oncology and Reproductive Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Fangrong Shen
- Department of Gynecologic Oncology and Reproductive Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Wei Hu
- Department of Gynecologic Oncology and Reproductive Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Robert L. Coleman
- Department of Gynecologic Oncology and Reproductive Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Anil K. Sood
- Department of Gynecologic Oncology and Reproductive Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
- Center for RNA Interference and Non-Coding RNAs, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| |
Collapse
|
14
|
Massey PR, Okman JS, Wilkerson J, Cowen EW. Tyrosine kinase inhibitors directed against the vascular endothelial growth factor receptor (VEGFR) have distinct cutaneous toxicity profiles: a meta-analysis and review of the literature. Support Care Cancer 2014; 23:1827-35. [PMID: 25471178 DOI: 10.1007/s00520-014-2520-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Accepted: 11/10/2014] [Indexed: 12/22/2022]
Abstract
PURPOSE Inhibition of the vascular endothelial growth factor receptor (VEGFR) with tyrosine kinase inhibitors (TKIs) is associated with cutaneous adverse effects that increase patient morbidity. Our objective was to examine the skin toxicity profile of anti-VEGFR TKIs and determine the changing incidence in clinical trials. METHODS PubMed was queried for phase II or III trials of anti-VEGFR TKIs between 2000 and 2013 involving ≥50 patients. Adverse events were abstracted, with results presented in both fixed and random effects models. Odds ratios (OR) and 95 % confidence intervals (CIs) were estimated for studies with at least two arms. RESULTS Across 82 included studies, all grades rash (OR, 2.68; 95 % CI, 2.45-2.94), hand-foot skin reaction (HFSR) (OR, 2.70; 95 % CI, 2.43-3.00), and pruritus (OR, 1.25; 95 % CI, 1.12-1.39) were associated with anti-VEGFR TKIs. Vandetanib had the highest incidence of rash (41 %), while sorafenib was most commonly associated with HFSR (37 %) and pruritus (14 %). The incidence of HFSR from 2000 to 2013 showed an upward trend (r (2) = 0.042, p = 0.10) and in sunitinib therapy increased significantly (r (2) = 0.237, p = 0.04). CONCLUSION The incidence of HFSR, rash, and pruritus varies considerably by drug. Our data suggest a continued need to address skin toxicities and improve reporting strategies.
Collapse
Affiliation(s)
- Paul R Massey
- Dell Medical School, The University of Texas at Austin, 601 E. 15th Street, CEC 2.470, Austin, TX, 78701, USA,
| | | | | | | |
Collapse
|
15
|
Mattison R, Jumonville A, Flynn PJ, Moreno-Aspitia A, Erlichman C, LaPlant B, Juckett MB. A phase II study of AZD2171 (cediranib) in the treatment of patients with acute myeloid leukemia or high-risk myelodysplastic syndrome. Leuk Lymphoma 2014; 56:2061-6. [PMID: 25329007 DOI: 10.3109/10428194.2014.977886] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Patients with acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) not fit for intensive treatment need novel therapy options. Vascular endothelial growth factor (VEGF) receptor inhibition is one potential mechanism by which AML and MDS could be treated. The receptor tyrosine kinase inhibitor AZD2171 (cediranib) has activity against VEGF receptors KDR and FLT-1. This multicenter phase II study was designed to test cediranib's activity in patients with AML or high-risk MDS. The primary endpoint was confirmed disease response defined as a composite of complete remission, partial remission or hematologic improvement. The study enrolled 23 subjects in the AML cohort and 16 subjects in the MDS cohort. There were no confirmed responses in either group. Since the study met the stopping rule after the first stage of enrollment, the trial was closed to further accrual. Common adverse events in both cohorts included thrombocytopenia, neutropenia, anemia, fatigue, dyspnea, diarrhea, nausea and dehydration.
Collapse
Affiliation(s)
- Ryan Mattison
- Carbone Comprehensive Cancer Center, University of Wisconsin , Madison, WI , USA
| | | | | | | | | | | | | |
Collapse
|
16
|
Hojjat-Farsangi M. Small-molecule inhibitors of the receptor tyrosine kinases: promising tools for targeted cancer therapies. Int J Mol Sci 2014; 15:13768-801. [PMID: 25110867 PMCID: PMC4159824 DOI: 10.3390/ijms150813768] [Citation(s) in RCA: 151] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Revised: 07/31/2014] [Accepted: 08/05/2014] [Indexed: 12/20/2022] Open
Abstract
Chemotherapeutic and cytotoxic drugs are widely used in the treatment of cancer. In spite of the improvements in the life quality of patients, their effectiveness is compromised by several disadvantages. This represents a demand for developing new effective strategies with focusing on tumor cells and minimum side effects. Targeted cancer therapies and personalized medicine have been defined as a new type of emerging treatments. Small molecule inhibitors (SMIs) are among the most effective drugs for targeted cancer therapy. The growing number of approved SMIs of receptor tyrosine kinases (RTKs) i.e., tyrosine kinase inhibitors (TKIs) in the clinical oncology imply the increasing attention and application of these therapeutic tools. Most of the current approved RTK-TKIs in preclinical and clinical settings are multi-targeted inhibitors with several side effects. Only a few specific/selective RTK-TKIs have been developed for the treatment of cancer patients. Specific/selective RTK-TKIs have shown less deleterious effects compared to multi-targeted inhibitors. This review intends to highlight the importance of specific/selective TKIs for future development with less side effects and more manageable agents. This article provides an overview of: (1) the characteristics and function of RTKs and TKIs; (2) the recent advances in the improvement of specific/selective RTK-TKIs in preclinical or clinical settings; and (3) emerging RTKs for targeted cancer therapies by TKIs.
Collapse
Affiliation(s)
- Mohammad Hojjat-Farsangi
- Department of Oncology-Pathology, Immune and Gene Therapy Lab, Cancer Center Karolinska (CCK), Karolinska University Hospital Solna and Karolinska Institute, Stockholm 17176, Sweden.
| |
Collapse
|
17
|
Small HY, Montezano AC, Rios FJ, Savoia C, Touyz RM. Hypertension due to antiangiogenic cancer therapy with vascular endothelial growth factor inhibitors: understanding and managing a new syndrome. Can J Cardiol 2014; 30:534-43. [PMID: 24786444 DOI: 10.1016/j.cjca.2014.02.011] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Revised: 02/20/2014] [Accepted: 02/20/2014] [Indexed: 12/21/2022] Open
Abstract
Novel antiangiogenic cancer therapies, particularly agents that block vascular endothelial growth factor (VEGF) signalling, have improved outcomes in patients with cancers and are now used as first-line therapies for some tumours. However, with VEGF inhibitors (VEGFIs) are new complications, particularly hypertension. VEGFI-induced hypertension is a dose-dependent phenomenon due to on-target effects rather than off-target effects. Increased blood pressure occurs in almost 100% of patients who take VEGFIs, with a subset who develop severe hypertension. Molecular mechanisms underlying VEGFI-induced hypertension are unclear, but endothelial dysfunction and increased vascular resistance, due to impaired nitric oxide signalling, reduced prostacyclin production, endothelin-1 (ET-1) upregulation, oxidative stress, and rarefaction have been implicated. Treatment of hypertension should be aimed at reducing the risk of short-term morbidity associated with hypertension while maintaining effective dosing of antiangiogenic therapy for optimal cancer treatment. Although specific guidelines are not yet available for the management of VEGFI-induced hypertension, angiotensin-converting enzyme inhibitors and dihydropyridine calcium channel blockers are commonly used. Severe hypertension might require reduction of VEGFI dosing, or in some cases, interruption of treatment. As more potent VEGFIs are developed and as more cancer patients are treated with VEGFIs, the burden of hypertension toxicity will increase. This will be further compounded as the use of antiangiogenic drugs broadens to include older patients and those with pre-existing cardiovascular disease. Here we focus on VEGF as a target for antiangiogenesis and how this affects increased blood pressure. Putative mechanisms underlying VEGFI-induced hypertension are highlighted and therapeutic strategies to manage such hypertension are discussed.
Collapse
Affiliation(s)
- Heather Yvonne Small
- Institute of Cardiovascular and Medical Sciences, British Heart Foundation Glasgow Cardiovascular Research Centre, University of Glasgow, UK
| | - Augusto C Montezano
- Institute of Cardiovascular and Medical Sciences, British Heart Foundation Glasgow Cardiovascular Research Centre, University of Glasgow, UK
| | - Francisco J Rios
- Institute of Cardiovascular and Medical Sciences, British Heart Foundation Glasgow Cardiovascular Research Centre, University of Glasgow, UK
| | | | - Rhian M Touyz
- Institute of Cardiovascular and Medical Sciences, British Heart Foundation Glasgow Cardiovascular Research Centre, University of Glasgow, UK.
| |
Collapse
|
18
|
Radaelli S, Stacchiotti S, Casali PG, Gronchi A. Emerging therapies for adult soft tissue sarcoma. Expert Rev Anticancer Ther 2014; 14:689-704. [DOI: 10.1586/14737140.2014.885840] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
|
19
|
Gavalas NG, Liontos M, Trachana SP, Bagratuni T, Arapinis C, Liacos C, Dimopoulos MA, Bamias A. Angiogenesis-related pathways in the pathogenesis of ovarian cancer. Int J Mol Sci 2013; 14:15885-909. [PMID: 23903048 PMCID: PMC3759892 DOI: 10.3390/ijms140815885] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Revised: 06/13/2013] [Accepted: 06/27/2013] [Indexed: 12/29/2022] Open
Abstract
Ovarian Cancer represents the most fatal type of gynecological malignancies. A number of processes are involved in the pathogenesis of ovarian cancer, especially within the tumor microenvironment. Angiogenesis represents a hallmark phenomenon in cancer, and it is responsible for tumor spread and metastasis in ovarian cancer, among other tumor types, as it leads to new blood vessel formation. In recent years angiogenesis has been given considerable attention in order to identify targets for developing effective anti-tumor therapies. Growth factors have been identified to play key roles in driving angiogenesis and, thus, the formation of new blood vessels that assist in "feeding" cancer. Such molecules include the vascular endothelial growth factor (VEGF), the platelet derived growth factor (PDGF), the fibroblast growth factor (FGF), and the angiopoietin/Tie2 receptor complex. These proteins are key players in complex molecular pathways within the tumor cell and they have been in the spotlight of the development of anti-angiogenic molecules that may act as stand-alone therapeutics, or in concert with standard treatment regimes such as chemotherapy. The pathways involved in angiogenesis and molecules that have been developed in order to combat angiogenesis are described in this paper.
Collapse
Affiliation(s)
- Nikos G. Gavalas
- Department of Clinical Therapeutics, Medical School, University of Athens, Alexandra Hospital, 80 Vas. Sofias Avenue, Athens 115 28, Greece; E-Mails: (N.G.G.); (L.M.); (S.-P.T.); (T.B.); (C.A.); (C.L.); (M.A.G.)
| | - Michalis Liontos
- Department of Clinical Therapeutics, Medical School, University of Athens, Alexandra Hospital, 80 Vas. Sofias Avenue, Athens 115 28, Greece; E-Mails: (N.G.G.); (L.M.); (S.-P.T.); (T.B.); (C.A.); (C.L.); (M.A.G.)
| | - Sofia-Paraskevi Trachana
- Department of Clinical Therapeutics, Medical School, University of Athens, Alexandra Hospital, 80 Vas. Sofias Avenue, Athens 115 28, Greece; E-Mails: (N.G.G.); (L.M.); (S.-P.T.); (T.B.); (C.A.); (C.L.); (M.A.G.)
| | - Tina Bagratuni
- Department of Clinical Therapeutics, Medical School, University of Athens, Alexandra Hospital, 80 Vas. Sofias Avenue, Athens 115 28, Greece; E-Mails: (N.G.G.); (L.M.); (S.-P.T.); (T.B.); (C.A.); (C.L.); (M.A.G.)
| | - Calliope Arapinis
- Department of Clinical Therapeutics, Medical School, University of Athens, Alexandra Hospital, 80 Vas. Sofias Avenue, Athens 115 28, Greece; E-Mails: (N.G.G.); (L.M.); (S.-P.T.); (T.B.); (C.A.); (C.L.); (M.A.G.)
| | - Christine Liacos
- Department of Clinical Therapeutics, Medical School, University of Athens, Alexandra Hospital, 80 Vas. Sofias Avenue, Athens 115 28, Greece; E-Mails: (N.G.G.); (L.M.); (S.-P.T.); (T.B.); (C.A.); (C.L.); (M.A.G.)
| | - Meletios A. Dimopoulos
- Department of Clinical Therapeutics, Medical School, University of Athens, Alexandra Hospital, 80 Vas. Sofias Avenue, Athens 115 28, Greece; E-Mails: (N.G.G.); (L.M.); (S.-P.T.); (T.B.); (C.A.); (C.L.); (M.A.G.)
| | - Aristotle Bamias
- Department of Clinical Therapeutics, Medical School, University of Athens, Alexandra Hospital, 80 Vas. Sofias Avenue, Athens 115 28, Greece; E-Mails: (N.G.G.); (L.M.); (S.-P.T.); (T.B.); (C.A.); (C.L.); (M.A.G.)
| |
Collapse
|
20
|
Kim SH, Jung YJ, Kang KP, Lee S, Park SK, Lee JH, Kim NH, Kim W. Decreased serum level and increased urinary excretion of vascular endothelial growth factor-C in patients with chronic kidney disease. Kidney Res Clin Pract 2013; 32:66-71. [PMID: 26877915 PMCID: PMC4713926 DOI: 10.1016/j.krcp.2013.05.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Revised: 04/22/2013] [Accepted: 04/30/2013] [Indexed: 11/10/2022] Open
Abstract
Background Interstitial tonicity increases vascular endothelial growth factor-C (VEGF-C), a lymphangiogenic factor in salt-induced hypertension. Therefore, it can be assumed that changes of serum VEGF-C level may be associated with increasing blood pressure. However, there is no report about the changes of serum VEGF-C levels in patients with chronic kidney disease (CKD). The aims of this study were to investigate the changes of serum and urine VEGF-C levels in patients with CKD stage 3–4 and to evaluate the relationship between blood pressure and serum VEGF-C levels in the patients with CKD stage 5 and hemodialysis. Methods Glomerular filtration rate (GFR) was assessed by the Modification of Diet in Renal Disease equation. Blood pressure and VEGF-C levels (serum and urine) were measured by enzyme-linked immunosorbent assay (ELISA) in nine patients with stage 3–4 CKD, 41 hemodialysis patients, and eight healthy individuals. Results The median serum level of VEGF-C in patients with stage 3–4 CKD and stage 5 hemodialysis significantly decreased in comparison with healthy individuals. Urinary VEGF-C excretion increased in patients with stage 3–4 CKD compared with healthy control patients. For 41 hemodialysis patients, the serum level of VEGF-C in patients with stage 1 or stage 2 hypertension with hemodialysis did not significantly increase when compared with prehypertension hemodialysis patients. Conclusion We demonstrated that circulating levels of VEGF-C were decreased in patients with CKD, and the decrease of VEGF-C in patients with stage 3–4 CKD coincided with an increase in the urinary excretion of VEGF-C.
Collapse
Affiliation(s)
- Sun Hee Kim
- Department of Internal Medicine and Research Institute of Clinical Medicine of Chonbuk National University-Chonbuk National University Hospital, Chonbuk National University Medical School, Jeonju, Korea
| | - Yu Jin Jung
- Department of Internal Medicine and Research Institute of Clinical Medicine of Chonbuk National University-Chonbuk National University Hospital, Chonbuk National University Medical School, Jeonju, Korea
| | - Kyung Pyo Kang
- Department of Internal Medicine and Research Institute of Clinical Medicine of Chonbuk National University-Chonbuk National University Hospital, Chonbuk National University Medical School, Jeonju, Korea
| | - Sik Lee
- Department of Internal Medicine and Research Institute of Clinical Medicine of Chonbuk National University-Chonbuk National University Hospital, Chonbuk National University Medical School, Jeonju, Korea
| | - Sung Kwang Park
- Department of Internal Medicine and Research Institute of Clinical Medicine of Chonbuk National University-Chonbuk National University Hospital, Chonbuk National University Medical School, Jeonju, Korea
| | - Ju-Hyung Lee
- Department of Preventive Medicine, Chonbuk National University Medical School, Jeonju, Korea
| | - Nam Ho Kim
- Department of Internal Medicine, Chonnam National University Medical School, Kwangju, Korea
| | - Won Kim
- Department of Internal Medicine and Research Institute of Clinical Medicine of Chonbuk National University-Chonbuk National University Hospital, Chonbuk National University Medical School, Jeonju, Korea
| |
Collapse
|
21
|
Cellular factors implicated in filovirus entry. Adv Virol 2013; 2013:487585. [PMID: 23365575 PMCID: PMC3556833 DOI: 10.1155/2013/487585] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2012] [Revised: 12/17/2012] [Accepted: 12/18/2012] [Indexed: 12/11/2022] Open
Abstract
Although filoviral infections are still occurring in different parts of the world, there are no effective preventive or treatment strategies currently available against them. Not only do filoviruses cause a deadly infection, but they also have the potential of being used as biological weapons. This makes it imperative to comprehensively study these viruses in order to devise effective strategies to prevent the occurrence of these infections. Entry is the foremost step in the filoviral replication cycle and different studies have reported the involvement of a myriad of cellular factors including plasma membrane components, cytoskeletal proteins, endosomal components, and cytosolic factors in this process. Signaling molecules such as the TAM family of receptor tyrosine kinases comprising of Tyro3, Axl, and Mer have also been implicated as putative entry factors. Additionally, filoviruses are suggested to bind to a common receptor and recent studies have proposed T-cell immunoglobulin and mucin domain 1 (TIM-1) and Niemann-Pick C1 (NPC1) as potential receptor candidates. This paper summarizes the existing literature on filoviral entry with a special focus on cellular factors involved in this process and also highlights some fundamental questions. Future research aimed at answering these questions could be very useful in designing novel antiviral therapeutics.
Collapse
|