ABSTRACT
<p><b>OBJECTIVE</b>To dynamically investigate the morphology of human gastric cancer SGC-7901 cell clones, and then compare the tumorigenic ability of different clones in order to identify the tumor stem cell clones.</p><p><b>METHODS</b>Clones derived from gastric cancer SGC-7901 cells were assessed by morphological observation, and the clone formation rate and proportion of each clone were calculated. The expression of CD44 and CDX2 in different clones was detected by immunofluorescence microscopy and Western blot. Furthermore, different clones were isolated and cultured, and their self-renewal property was assayed. Cells of different clones were subcutaneously inoculated into nude mice and the tumorigenic ability of each group was determined.</p><p><b>RESULTS</b>Clones derived from gastric cancer SGC-7901 cells had three types, i.e. clones of tight, transitional and loose types. The total clone formation rate was (9.80 ± 1.07)%, and the proportion of tight, transitional and loose type clones was 10.2%, 56.0% and 33.8%, respectively. The results of immunofluorescence microscopic examination showed that the signal of CD44 was significantly stronger in the tight clones than in the transitional and loose clones, however, the signal of CDX2 was weakest in the tight colonies. The results of Western blot were consistent with that of immunofluorescence microscopic observation. SGC-7901 cells of tight clones possessed strong ability of self-renewal and in vivo tumorigenicity in the nude mice.</p><p><b>CONCLUSION</b>SGC-7901 cell clones vary in morphology and differentiation, and the tight type clones may include rich gastric cancer stem cells.</p>
Subject(s)
Animals , Female , Humans , Mice , CDX2 Transcription Factor , Cell Differentiation , Cell Line, Tumor , Cell Proliferation , Clone Cells , Classification , Homeodomain Proteins , Metabolism , Hyaluronan Receptors , Metabolism , Mice, Nude , Neoplasm Transplantation , Neoplastic Stem Cells , Cell Biology , Metabolism , Random Allocation , Stomach Neoplasms , Metabolism , PathologyABSTRACT
<p><b>OBJECTIVE</b>To explore the effects and associated mechanism of phosphatase of regenerating liver cell-3 (PRL-3) on the invasion of human colon cancer cell.</p><p><b>METHODS</b>After colon cancer cell line HCT116 was transfected with PRL-3 small interfering RNA (siRNA), the mRNA and protein expression of PRL-3 and matrix metalloproteinase 2 (MMP-2) and MMP-9 were determined by real time RT-PCR and Western blot respectively. The anchorage-independent growth was examined using clone formation assay in soft agar, and invasion ability was evaluated by boyden chamber model. Then the transfected HCT116 cells were implanted into nude mice and the tumor growth was observed.</p><p><b>RESULTS</b>PRL-3 siRNA could inhibit anchorage-independent growth of HCT116 cells in a dose-dependent manner in vitro. The mRNA and protein expression of MMP-2 and MMP-9 were down-regulated by PRL-3 siRNA. HCT116 cells invaded striated muscle and vessels in control nude mice but such phenomena were not found in transfected HCT116-implanted nude mice in vivo.</p><p><b>CONCLUSION</b>PRL-3 siRNA inhibit the invasion of colon cancer cells possibly through the down-regulation of MMP-2 and MMP-9.</p>