[Effect of peptide-conjugated quantum dots on the tumorigenicity and lymph node metastasis of human tongue squamous cell carcinoma cell line Tca8113 and mouse uterine cervix carcinoma U14 in vivo].

OBJECTIVE: To observe the effect of peptide-conjugated quantum dots with a maximal emission of 655 nm (QD655) on growth, proliferation, apoptosis and lymphatic metastasis of human tongue squamous cell carcinoma cell line Tca8113 and mouse uterine cervix carcinoma U14 in vivo. METHODS: Tca8113 and U14 cells were labeled by QD655 (Tca8113-QD655, U14-QD655). Tca8113-QD655 and U14-QD655 were inoculated subcutaneously into nude mice and Kunming mice. The tumor formation of Tca8113-QD655 and Tca8113, U14-QD655 and U14 was observed and compared in vivo. The proliferation and apoptosis of Tca8113-QD655 and Tca8113, U14-QD655 and U14 cells from tumors formed in vivo were analyzed by flow cytometry. U14-QD655 and U14 were inoculated into the buccal mucosa of Kunming mice to establish the cervical lymph node metastasis model of buccal cancer. The cervical lymph node metastatic ability of U14-QD655 and U14 was compared. RESULTS: The tumor weight and volume of Tca8113-QD655 and Tca8113, U14-QD655 and U14 in vivo were not significantly different (P>0.05), the cell proliferation index and apoptosis index of Tca8113-QD655 and Tca8113, U14-QD655 and U14 in vivo were not significantly different (P>0.05). The cervical lymph node metastasis rate of U14-QD655 and U14 buccal cancer were not significantly different (P>0.05). CONCLUSIONS: QD showed no effects on tumorigenicity and lymph node metastasis of Tca8113 and U14 cells. These results provide the scientific basis for noninvasive imaging and long-term tracing study.

In vivo study of the effects of peptide-conjugated near-infrared fluorescent quantum dots on the tumorigenic and lymphatic metastatic capacities of squamous cell carcinoma cell line Tca8113 and U14.

Quantum dots (QDs) have great potential in non-invasive monitoring and imaging of tumor cells in vivo, but it is unknown if QDs affect their tumorigenesis and metastasis. Here, we applied peptide-conjugated near-infrared fluorescent QDs (NIRF-QDs) to label the squamous cell carcinoma cells Tca8113 and U14. We tested the proliferation and apoptotic capacities of both cells, and the capacity of cervical lymph node metastasis after tumorigenesis in U14 cells'. We find that QDs do not affect the tumor cells' capacities to grow, proliferate, and metastasize. Our study provides critical data to support the application of NIRF-QDs in non-invasive monitoring and imaging of tumor cells in vivo.

[Preparing of semiconductor quantum dots-Smad4 monoclonal antibody fluorescent probes and identification of their ability of specific immuno-recognition].

OBJECTIVE: To prepare semiconductor quantum dots (SQD)-Smad4 monoclonal antibody fluorescent probes and to detect the optical qualities and the ability of specific recognition of the probes. METHODS: SQD were chemically modified with Smad4 monoclonal antibody proteins to prepare water soluble probes, and the fluorescence intensity, photostability, absorption spectra and emission spectra of the probes were studied. The location of Smad4 in rat dental papillae cells (RDPC) was examined by SP anti-Smad4 immunocytochemical method and SQD-Smad4 direct immunofluorescent imaging. RESULTS: SQD and monoclonal antibody covalently bonded to form the fluorescent probes which could specifically recognize Smad4 in RDPC. These fluorescent probes still had properties, including broad absorption band, narrow emission band, high fluorescence intensity and photostability. CONCLUSIONS: SQD and monoclonal antibody could covalently bond to form the fluorescent probes with distinct optics character and ability of specific recognization, which provides the scientific evidence that SQD trace the molecular movement in living cells in long-term, in situ and in real time.

[Preparing of semiconductor quantum dots-Smad2 monoclonal antibody fluorescent probes and testing of its related properties].

OBJECTIVE: To prepare semiconductor quantum dots (QDs)-Smad2 monoclonal antibody fluorescent probes, to detect the optical qualities and the ability to specific recognition of Smad2 in rat dental papillae cells (RDPC) of quantum dots-Smad2 monoclonal antibody fluorescent probes. METHODS: (1) QDs were chemically modified with Smad2 proteins to prepare water soluble QDs-Smad2 monoclonal antibody fluorescent probes which were purified after preparation. (2) The absorption band and emission band of these probes were obtained through ultraviolet spectrophotometer and fluorospectrophotometer, the shape, fluorescence intensity and photochemistry stability of these probes were studied through confocal laser scanning fluorescence microscopy. (3) Before the location of Smad2 proteins in RDPC was studied with anti-Smad2 immunocytochemical method and direct immunofluorescence imaging, RDPC were incubated with transforming growth factor-beta1 (TGF-beta1), and the related optical qualities of quantum dots-Smad2 monoclonal antibody fluorescent probes in RDPC were detected. RESULTS: QDs and monoclonal antibody linked together through covalent bond to form the fluorescent probes which could specifically and effectively recognize Smad2 proteins in RDPC. These fluorescent probes still had good properties, including broad excite spectra, narrow emission spectra, high fluorescence intensity and photostability. CONCLUSION: QDs and monoclonal antibody could link together through covalent bond to form the nanometer molecular probes with distinct optics character and photostability, which provides the scientific evidence that QDs can visualize the molecular movement in living cells in long-term, in situ and in real time.

[Effect of semiconductor quantum dots on cyto-biological behavior of tongue squamous cell carcinoma cell line Tca8113].

OBJECTIVE: To study the effect of semiconductor quantum dots (QD), a kind of new luminescent inorganic non-crystals on biological behavior of tongue squamous cell carcinoma cell line Tca8113. METHODS: Different concentrations of QD were cocultured with Tca8113 cells, and the status of cancer cell growth in three experimental groups and control was compared respectively. Tca8113 cells were labeled by QD (Tca8113-QD), and then transwell chambers and washing away method were used to detect the difference of invasion and metastatic ability between Tca8113-QD and Tca8113 cells. RESULTS: The different concentrations of QD showed no negative effects on growth of Tca8113 cells. The ability of invasion, attachment and chemotaxis movement of Tca8113 cells were not significantly different between the experimental groups and control. CONCLUSIONS: QD showed no effects on growth, invasion and metastatic ability of Tca8113 cells and may serve as a new fluorescence probe in living tumor cell study.