ABSTRACT
Background: Metastasis suppressor 1 (MTSS1), a potential metastasis suppressor gene associated with tumor progression, may play an important role in cancer development. Our previous study demonstrated that MTSS1 was downregulated significantly when gastric cancer (GC) progressed and metastasized, suggesting that MTSS1 may be involved in the physiopathologic mechanism of GC. Purpose: The objective of this study was to evaluate the effect of MTSS1 expression on the biological behavior of gastric cancer cell both in vitro and in vivo. Materials and methods: The gain-and-loss function of MTSS1 in GC cells were analyzed after transfection with pEGFP-N1-MTSS1 and ShRNA431. Proliferation and invasion abilities were measured by means of plate clone formation assay and transwell assay. To further explore the underlying mechanism of MTSS1-induced tumor restrain, cell cycle distribution was analyzed using flow cytometry. Results: The results revealed that overexpression of MTSS1 significantly reduced proliferation, migration and invasion of GC cells in vivo and in vitro, while downregulation of MTSS1 had the opposite biological manifestations. Moreover, overexpression of MTSS1 induced accumulation of GC cells in G2/M phase, increased phosphorylated Cdc2 expression and decreased Cdc25C and cyclinB1 levels, suggesting MTSS1 could cause G2/M cell cycle arrest. Conclusion: Our data provided insight into an important role for MTSS1 in suppressing tumor cell proliferation, invasion and migration, indicating that MTSS, as a functional tumor suppressor in GC, could be a potential therapeutic target to prevent GC metastasis.
ABSTRACT
<p><b>OBJECTIVE</b>To screen hepatocellular carcinoma (HCC) autoantibodies as diagnostic biomarkers or therapy targets by serologic proteome analysis (SERPA).</p><p><b>METHODS</b>Total proteins extracted from human HCC cell line HCCLM3 were separated by two-dimensional electrophoresis (2-DE) and then transferred onto PVDF membranes, which were subsequently incubated with sera from HCC, hepatitis B virus (HBV) infected patients or healthy volunteers. All immuno-reactive protein spots on blot films were matched to those on 2-DE gel maps by image analysis and identified by matrix-assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOF-MS/MS).</p><p><b>RESULTS</b>2-DE gel maps of HCCLM3 and corresponding blot films of good quality and reproducibility were established. The number of spots on HCCLM3 2-DE reference gel totaled 603 and those on HCC, HBV and healthy sera blotted films were 70.75+/-24.25, 68.5+/-23.44 and 41.38+/-15.05, respectively. Blot films of HCC and HBV groups had more spots than those of the healthy group (P < 0.05) while no significance was found between films of HCC and HBV groups. By identification, those HCC autoantibodies could be classified as nuclear proteins, cytoskeleton proteins, heat shock proteins and metabolic enzymes.</p><p><b>CONCLUSION</b>Serological proteome analysis is a high throughput technique for screening tumor autoantibodies. Those newly identified HCC associated tumor antigens and corresponding autoantibodies can be used in the early diagnosis or immuno-therapy of HCC.</p>
