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- Koga, Shigehiro, et al.
(författare)
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In vivo subcellular imaging of tumors in mouse models using a fluorophore-conjugated anti-carcinoembryonic antigen antibody in two-photon excitation microscopy
- 2014
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Ingår i: Cancer Science. - : Wiley. - 1347-9032 .- 1349-7006. ; 105:10, s. 1299-1306
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Tidskriftsartikel (refereegranskat)abstract
- Recently, there has been growing interest in applying fluorescence imaging techniques to the study of various disease processes and complex biological phenomena in vivo. To apply these methods to clinical settings, several groups have developed protocols for fluorescence imaging using antibodies against tumor markers conjugated to fluorescent substances. Although these probes have been useful in macroscopic imaging, the specificity and sensitivity of these methods must be improved to enable them to detect micro-lesions in the early phases of cancer, resulting in better treatment outcomes. To establish a sensitive and highly specific imaging method, we used a fluorophore-conjugated anti-carcinoembryonic antigen (CEA) antibody to perform macroscopic and microscopic in vivo imaging of inoculated cancer cells expressing GFP with or without CEA. Macroscopic imaging by fluorescence zoom microscopy revealed that bio-conjugation of Alexa Fluor 594 to the anti-CEA antibody allowed visualization of tumor mass consisting of CEA-expressing human cancer cells, but the background levels were unacceptably high. In contrast, microscopic imaging using a two-photon excitation microscope and the same fluorescent antibody resulted in subcellular-resolution imaging that was more specific and sensitive than conventional imaging using a fluorescence zoom microscope. These results suggest that two-photon excitation microscopy in conjunction with fluorophore-conjugated antibodies could be widely adapted to detection of cancer-specific cell-surface molecules, both in cancer research and in clinical applications.
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2. |
- Tsubakihara, Yutaro, et al.
(författare)
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TGF beta selects for pro-stemness over pro-invasive phenotypes during cancer cell epithelial-mesenchymal transition
- 2022
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Ingår i: Molecular Oncology. - : John Wiley & Sons. - 1574-7891 .- 1878-0261. ; 16:12, s. 2330-2354
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Tidskriftsartikel (refereegranskat)abstract
- Transforming growth factor beta (TGF(beta) induces epithelial-mesenchymal transition (EMT), which correlates with sternness and invasiveness. Mesenchymal-epithelial transition (MET) is induced by TGF beta withdrawal and correlates with metastatic colonization. Whether TGF beta promotes sternness and invasiveness simultaneously via EMT remains unclear. We established a breast cancer cell model expressing red fluorescent protein (RFP) under the E-cadherin promoter. In 2D cultures, TGF beta induced EMT, generating RFPlow cells with a mesenchymal transcriptome, and regained RFP, with an epithelial transcriptome, after MET induced by TGF beta withdrawal. RFPlow cells generated robust mammospheres, with epithelio-mesenchymal cell surface features. Mammospheres that were forced to adhere generated migratory cells, devoid of RFP, a phenotype which was inhibited by a TGF beta receptor kinase inhibitor. Further stimulation of RFPlow mammospheres with TGF beta suppressed the generation of motile cells, but enhanced mammosphere growth. Accordingly, mammary fat-pad-transplanted mammospheres, in the absence of exogenous TGF beta treatment, established lung metastases with evident MET (RFPhigh cells). In contrast, TGF beta-treated mammospheres revealed high tumour-initiating capacity, but limited metastatic potential. Thus, the biological context of partial EMT and MET allows TGF beta to differentiate between pro-sternness and pro-invasive phenotypes.
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