ABSTRACT
Multicellular tumor spheroids (MCTS) can simulate the structure and metabolic characteristics of tumors in vivo, which is of great significance to study the metabolic phenotype of tumor cells and the mechanism of drug intervention. In this study, esophageal cancer MCTS were constructed, and MCTS frozen sections were prepared after treated with different formulations of paclitaxel (PTX) including common PTX injection, PTX liposome and albumin bound PTX. MCTS mass spectrometry imaging analysis method was established by using air flow assisted desorption electrospray ionization mass spectrometry imaging (AFADESI-MSI). The visualization of the permeation and enrichment process of PTX in MCTs after PTX treatment was realized, and the spatially resolved metabolomics of PTX injection group was studied. The results showed that the permeation and enrichment behavior of PTX in MCTs model were related to the formulations. The changes of endogenous metabolites in MCTs of esophageal cancer after treated with PTX injection had temporal and spatial characteristics. The metabolic changes of MCTS during the initial 0-4 hours were dominated by the down-regulation of middle-high polarity metabolites and some lipids in the central region of MCTS, while the metabolic changes of MCTS during 8-72 hours were mainly up-regulated by lipid metabolites in the peripheral region of MCTS. The combination of in vivo tumor-associated MCTs model with label free, highly sensitive and high coverage mass spectrometry imaging technology provided a new method and strategy for the study of pharmacometabolomics.
ABSTRACT
Hispidulin(HPDL) chitosan microspheres were prepared in this study to deliver HPDL to the lesion sitevia intravenous injection, and further evaluate their anticancer effects in vitro and the growth inhibition effect on A549 cells spheroids. HPDL chitosan microspheres were prepared by emulsion crosslinking method with chitosan as a drug carrier and the amount of HPDL was determined by high performance liquid chromatography (HPLC). The morphology of microspheres was observed under laser scanning confocal microscope. Additionally, the drug release amount of targeting microspheres was detected by dialysis method. Furthermore, the anti-proliferative effects against A549 lung cancer cells were tested by sulforhodamine B (SRB) method, and the effects of HPDL chitosan micrpsphereson early apoptosis of A549 cellswere determined by flow cytometry. A549 cells tumor spheroids were developed in vitro and then HPDL chitosan microspheres were added. On the 0, 1, 3, 7 d after adding the drugs, the inverted microscope was used to observe the mythologicaland volume changes of A549 cells spheroids. The encapsulation efficiency of HPDL chitosan microspheres was （75.32±0.52）%, and the drug loading amount was （7.76±0.67）%. Meanwhile, the microspheres were round shaped andhad smooth surface. The HPDL chitosan microspheres exhibited stronger inhibitory effects on A549 lung cancer cells. The results of flow cytometry indicated that, the early apoptosis rate of lung cancer A549 cells was （37.0±0.75）% at 24 h cells culture after drug administration. The volume of tumor spheroid was significantly inhibited, which had been shrunk by (50.09±11.06)% after the treatment by drug-loaded microsphere at day 7 as compared with blank group; meanwhile, the cells surface were obviously lysed. The preparation method in this research was simple and practicable, and the microspheres prepared with this method were round and smooth, with high encapsulation efficiency, which can significantly inhibit proliferation of lung adenocarcinoma A549 cells and induce cell apoptosis, and at the same time can cause lysisand death of A549 cell tumor spheroid.
ABSTRACT
@#In comparison with the traditional two-dimensional tumor cell culture, the three-dimensional tumor spheroid culture can not only provide with an in vivo-like growth environment for tumor cells, but also maintain maximum cell activities. Therefore, the three-dimensional tumor spheroid culture is widely used in oncology research. In particular, the three-dimensional tumor cells retain the material and structural basis of the microenvironment of tumor in vivo, which is closer to the actual physiological environment, allowing it to be an ideal in vitro model for evaluating the tumor treatment response and drug resistance in tumors. This review summarizes the mechanisms of drug resistance in three-dimensional tumor cells, especially those induced by the morphology and microenvironment of three-dimensional tumor spheres, and puts forward the problems existing in the current three-dimensional tumor cells model, as well as the future development direction.
ABSTRACT
PURPOSE: To establish new in vitro model systems that better reflect in vivo condition, multicellular tumor spheroids(MTS) and raft culture were developed using cell lines of squamous cell carcinoma(SCCHN) of the head and neck. In these 3-dimensional systems, the expression of cell surface molecules which are important for modulation of physiology of tumor cells were studied with or without the treatment of interferon(IFN)-gamma. MATERIALS AND METHODS: Four SCCHN cell lines were used for MTS and raft culture. The effects of interferon-gamma on SCCHN cells were examined by immunohistochemistry. RESULTS: All cell lines formed MTS, but only Tu-138 showed a good stratification at the air-liquid interface in the raft culture system. Immunohistochemical studies of MTS using monoclonal antibodies revealed a strong staining for MHC class I, no staining for MHC-DR, a weak patch expression of ICAM-1 and a central strong staining for integrin a 6. Staining patterns were similar for the raft cultures except integrin a 6(intense full-thickness positivity). In both systems, IFN-gamma enhanced the expression of MHC-DR and ICAM-1. No significant change was found in the expression of MHC class I and integrin a 6. CONCLUSIONS: MTS and raft culture system were established successfully from the SCCHN cell lines. IFN-gamma can modulate the surface molecules of tumor cells in the 3-dimensional culture systems.