Objectives Colorectal cancer (CRC) is the third most common malignancy and the fourth most frequent cause of cancer deaths worldwide. The five-year overall survival rate is 40-60% based on surgery, adjuvant chemotherapy and radiotherapy. Therefore, newly developed or more effective adjuvant therapies are needed. The aim of this study we applied is using the multimodality imaging to evaluate the therapeutic efficacy of the liposome encaged with vinorelbine (VNB) and 111In-oxine on human colorectal adenocarcinoma HT-29/tk-luc mouse xenografts. Methods Dual reporter gene, herpes simplex virus-1-thymidine kinase and luciferase, was stably transfected into human colorectal HT29 cancer cells. Multimodality imaging including gamma scintigraphy, positron emission tomography (PET), bioluminescence imaging (BLI) and whole-body autoradiography (WBAR) were applied for evaluating the therapeutic efficacy when tumor size was about 100mm3. Results In pharmacokinetics data, the areas under the curve (AUC) of PEGy- lated liposome is over 10 folder high than free durg, and the tumor/blood ratios increased with time respectively at 48 h postinjection, have the tumor/muscle ratios of 111In-VNB- liposome were 12.73. In vivo tumor growth rate showed that significant tumor control was achieved in the group of 111In-VNB-liposome (100mCi radioactivity, 3 mg/kg VNB). Conclusions In this study, we have demonstrated tumor passive targeting of liposomal drug and a non-invasive imaging technique with thymidine kinase and luciferase dual reporter gene for evaluation of tumor treatment efficacy in vivo.
Date:
2009-05
Relation:
Journal of Nuclear Medicine. 2009 May;50(Suppl. 2):Meeting Abstract 2306.
