ABSTRACT
Secreted protein, acidic and rich in cysteine (SPARC) is expressed in numerous types of tumors and is suggested to have prognostic value. Moreover, because of its strong affinity for albumin, and hence albumin-bound drugs, SPARC has increasingly become a focus for research. In this study, we aimed to determine SPARC expression in patients with non-small cell lung cancer (NSCLC) and investigate the association of SPARC with disease prognosis. Tissue microarrays were constructed with specimens from 105 patients with NSCLC treated at Sun Yat-sen University Cancer Center, and immunohistochemical analysis was performed on these tissue microarrays to assess SPARC expression. Our results showed that SPARC expression status did not significantly relate with age, gender, and tumor stage. However, SPARC was expressed more frequently in squamous cell carcinoma than in adenocarcinoma (75% vs. 43.5%, P = 0.004). Patients with smoking history had higher SPARC expression than non-smokers (68.2% vs. 33.3%, P = 0.002). In both univariate and multivariate analyses, SPARC was a prognostic factor of overall survival (HR = 0.32; 95% CI: 0.16-0.65) but not disease-free survival. Our study indicates that SPARC expression is higher in squamous cell carcinoma than in adenocarcinoma in NSCLC. Most notably, SPARC can be used as a prognostic factor for NSCLC.
Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Adenocarcinoma , Metabolism , Pathology , Carcinoma, Non-Small-Cell Lung , Metabolism , Pathology , Carcinoma, Squamous Cell , Metabolism , Pathology , Disease-Free Survival , Immunohistochemistry , Lung Neoplasms , Metabolism , Pathology , Neoplasm Staging , Osteonectin , Metabolism , Proportional Hazards Models , Smoking , Survival RateABSTRACT
<p><b>OBJECTIVE</b>To assess suppression effects of vector-based small interfering RNA (siRNA) on vascular endothelial growth factor (VEGF) expression of human tongue squamous carcinoma cell line (Tca8113) in vitro.</p><p><b>METHODS</b>Two siRNA targeting VEGF constructed in eukaryotic expression vector (Pu-VEGF-siRNA1, Pu-VEGF-siRNA2), eukaryotic expression vector as the experiment control, all of which were transfected into Tca8113 cells with Lipofectamine 2000. Non-transfection cell was used as negative control. VEGF mRNA and protein were detected by reverse transcription polymerase chain reaction (RT-PCR), immunohistochemistry and enzyme linked immunosorbent assay (ELISA), respectively.</p><p><b>RESULTS</b>Compared to the experimental and negative controls, the expression of VEGF mRNA and protein were significantly decreased in the Pu-VEGF-siRNA1 group and Pu-VEGF-siRNA2 group. But there were no significant differences between two controls (P > 0.05).</p><p><b>CONCLUSION</b>Vector-based siRNAs targeting VEGF are efficient in down-regulating VEGF expression in Tca8113 cells.</p>