Increasing levels of wealth and educational attainment were associated with an increased likelihood of having hypertension and hyperglycaemia in Bangladesh.
Purpose:To use near-infrared (NIR) optical imaging to assess the therapeutic susceptibility and drug dosing of orthotopic human breast cancers implanted in mice treated with molecularly targeted therapy.
Materials and Methods:This study was approved by the institutional animal care and use committee. Imaging probes were synthesized by conjugating the human epidermal growth factor receptor type 2 (HER2)-specific antibody trastuzumab with fluorescent dyes. In vitro probe binding was assessed with flow cytometry. HER2-normal and HER2-overexpressing human breast cancer cells were orthotopically implanted in nude mice. Intravital laser scanning fluorescence microscopy was used to evaluate the in vivo association of the probe with the tumor cells. Mice bearing 3-5-mm-diameter tumors were intravenously injected with 0.4 nmol of HER2 probe before or after treatment. A total of 123 mice were used for all in vivo tumor growth and imaging experiments. Tumor fluorescence intensity was assessed, and standard fluorescence values were determined. Statistical significance was determined by performing standard analysis of variance across the imaging cohorts.
Results:HER2 probe enabled differentiation between HER2-normal and HER2-overexpressing human breast cancer cells in vitro and in vivo, with binding levels correlating with tumor trastuzumab susceptibility. Serial imaging before and during trastuzumab therapy revealed a significant reduction (P Ͻ .05) in probe binding with treatment and thus provided early evidence of successful HER2 inhibition days before the overall reduction in tumor growth was apparent.
Conclusion:NIR imaging with HER2-specific imaging probes enables evaluation of the therapeutic susceptibility of human mammary tumors and of drug dosing during HER2-targeted therapy with trastuzumab. This approach, combined with tomographic imaging techniques, has potential in the clinical setting for determining patient eligibility for and adequate drug dosing in molecularly targeted cancer therapies. RSNA, 2008
Cancer cells interact with surrounding stromal fibroblasts during tumorigenesis, but the complex molecular rules that govern these interactions remain poorly understood thus hindering the development of therapeutic strategies to target cancer stroma. We have taken a mathematical approach to begin defining these rules by performing the first large-scale quantitative analysis of fibroblast effects on cancer cell proliferation across more than four hundred heterotypic cell line pairings. Systems-level modeling of this complex dataset using singular value decomposition revealed that normal tissue fibroblasts variably express at least two functionally distinct activities, one which reflects transcriptional programs associated with activated mesenchymal cells, that act either coordinately or at cross-purposes to modulate cancer cell proliferation. These findings suggest that quantitative approaches may prove useful for identifying organizational principles that govern complex heterotypic cell-cell interactions in cancer and other contexts.
Many altered pathways in cancer cells depend on growth factor receptors. In primary malignant gliomas, the amplification/ alteration of the epidermal growth factor receptor (EGFR) has been shown to play a significant role in enhancing glioma burden. In an effort to dissect the role of EGFR expression in glioma progression in vivo and evaluate targeted therapies for gliomas, we have genetically engineered glioma cells to visualize the dynamics of EGFR and targeted therapies in real time in vivo. Using engineered lentiviral vectors bearing fusions between EGFR and its exon 2 to 7 deleted variant (EGFRvIII) with green fluorescent protein (GFP) and Renilla luciferase (Rluc), we show that there is a direct correlation between EGFR expression and glioma cell proliferation in the initial stages of glioma progression. To monitor and evaluate EGFR-targeted therapies, we have engineered (a) short hairpin RNAs (shRNA) and (b) clinically used monoclonal antibody, cetuximab. Using EGFR-GFP-Rluc/firefly luciferase (Fluc)-DsRed2 glioma model, we show that both shRNAs and cetuximab result in a considerable reduction in glioma cell proliferation in culture and glioma burden in vivo that can be monitored in real time at a cellular resolution. This study serves as a template to follow the role of growth factor receptor expression in tumor progression and to image therapeutic efficacy of targeted therapies in cancer. [Cancer Res 2007;67(15):7335-42]
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