You will be shown an abstract from a biomedical research paper. Given this abstract, your task is to extract all unique entities of the following types: ["HealthCareActivity", "InjuryOrPoisoning", "BodySubstance", "IntellectualProduct", "AnatomicalStructure", "SpatialConcept", "Chemical", "Bacterium", "MedicalDevice", "Organization", "BiomedicalOccupationOrDiscipline", "Finding", "BiologicFunction", "Virus", "ResearchActivity", "ClinicalAttribute", "PopulationGroup", "Eukaryote", "BodySystem", "Food", "ProfessionalOrOccupationalGroup"].

Please return the output as a JSON object of the format: {"Virus": ["HIV", ...], "Bacterium": ["MRSA", ...], "AnatomicalStructure": ["Lung", ...], "BodySystem": ["CNS", ...], "BodySubstance": ["Serum", ...], "Finding": ["Headache", ...], "InjuryOrPoisoning": ["Fracture", ...], "BiologicFunction": ["Death", ...], "HealthCareActivity": ["Biopsy", ...], "ResearchActivity": ["Clinical trial", ...], "MedicalDevice": ["Lenses", ...], "SpatialConcept": ["Camps", ...], "BiomedicalOccupationOrDiscipline": ["Forensic medicine", ...], "Organization": ["WHO", ...], "ProfessionalOrOccupationalGroup": ["Provider", ...], "PopulationGroup": ["Swimmers", ...], "Chemical": ["Gold", ...], "Food": ["Rice", ...], "IntellectualProduct": ["RPAM", ...], "ClinicalAttribute": ["Biomarker", ...], "Eukaryote": ["Dogs", ...]}. The keys should be entity types and values should be lists of extracted entities belonging to the corresponding type. If you cannot find entities belonging to a specific type, the value should be [].

Only output the JSON object and do not include any additional text.

Abstract:

Effect of Xenotransplantation Site on MicroRNA Expression of Human Colon Cancer Stem Cells Cancer stem cells (CSCs) have a high tumorigenic ability to form patient-derived tumor xenografts (PDXs). PDXs are an attractive pre-clinical model, but gene expression and biological behavior of cancer cells in the tumor will change during establishment and passage of PDXs. Human colon cancer PDX was established and passaged either subcutaneously or orthotopically into the murine intestine. Histology and flow cytometric profile of the surgical specimen and the PDX were analyzed. CSCs were then isolated from the tumors and their microRNA (miRNA) expression was analyzed by semi-quantitative polymerase chain reaction. The surgical specimens and PDXs were histologically similar. The size of CSC population increased and expression of miRNA s in CSCs changed in the passaged PDXs. Expression of oncogenic miRNAs was highly up-regulated in the CSCs of the orthotopically passaged PDXs. The xenotransplantation site and the number of tumor passages affect the miRNA expression of human colon CSCs.
{"AnatomicalStructure": ["Stem Cells", "CSCs", "CSC", "Cancer stem cells", "intestine", "cancer cells", "colon"], "Bacterium": [], "BiologicFunction": ["Expression", "PDXs", "tumors", "patient-derived tumor xenografts", "Colon Cancer", "tumor", "affect", "expression", "colon cancer", "gene expression", "tumorigenic", "up-regulated", "PDX"], "BiomedicalOccupationOrDiscipline": ["Histology", "histologically"], "BodySubstance": [], "BodySystem": [], "Chemical": ["microRNA", "miRNAs", "MicroRNA", "oncogenic", "miRNA"], "ClinicalAttribute": [], "Eukaryote": ["murine", "human", "Human"], "Finding": [], "Food": [], "HealthCareActivity": ["passages", "passaged", "flow cytometric", "profile", "semi-quantitative polymerase chain reaction", "surgical", "xenotransplantation", "Xenotransplantation"], "InjuryOrPoisoning": [], "IntellectualProduct": ["pre-clinical model"], "MedicalDevice": [], "Organization": [], "PopulationGroup": ["population"], "ProfessionalOrOccupationalGroup": [], "ResearchActivity": ["analyzed"], "SpatialConcept": ["Site", "size", "orthotopically", "site", "subcutaneously"], "Virus": []}