ABSTRACT
<p><b>BACKGROUND</b>Bcl-2, the anti-apoptotic protein is overexpressed in the majority of gastric cancers and associated with its pathogenesis. To better understanding of the role of Bcl-2, RNA interference (RNAi) was used to inhibit Bcl-2 expression in the human gastric cancer cells in vitro and in vivo.</p><p><b>METHODS</b>Bcl-2 small interfering RNA (siRNA) was transfected into human gastric cancer cells SGC-7901, and Bcl-2 expression was monitored by real-time polymerase chain reaction (PCR) and Western blot. Cell proliferation, apoptosis, and telomerase activity were examined by MTT, flow cytometry, and TRAP assay, respectively. Gastric cancer cells treated with 100 nmol/L Bcl-2 siRNA were subcutaneously transplanted into nude mice and tumor growth was assessed.</p><p><b>RESULTS</b>Bcl-2 siRNA significantly inhibited the expression of Bcl-2 in human gastric cancer cells at both mRNA and protein levels in a time- and dose-dependent manner. Bcl-2 siRNA also decreased telomerase activity (by 78.76%) and increased the rate of apoptosis (by 37.47%). SGC-7901 cell growth was also significantly suppressed in vivo and in vitro.</p><p><b>CONCLUSIONS</b>Bcl-2 expression knockdown suppressed the growth of gastric cancer cells. Thus, Bcl-2 may play a very important role in carcinogenesis of gastric cancer and its knockdown may offer a new potential gene therapy approach for human gastric cancer in future.</p>
Subject(s)
Animals , Humans , Male , Mice , Apoptosis , Cell Line, Tumor , Cell Proliferation , Mice, Inbred BALB C , Mice, Nude , Proto-Oncogene Proteins c-bcl-2 , Genetics , RNA Interference , RNA, Small Interfering , Genetics , Stomach Neoplasms , Pathology , Therapeutics , TransfectionABSTRACT
<p><b>OBJECTIVE</b>To investigate the application of proteomics in the field of serology,and to screen the differential expression proteins related with poorly differentiated gastric carcinoma.</p><p><b>METHODS</b>Two-dimensional electrophoresis (2-DE) was applied to segregate the total proteins in the serum form gastric cancer patients and health volunteers. After staining,the differential expression proteins were analyzed using PDQuest software,and identified using matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF-MS).</p><p><b>RESULTS</b>Electrophoresis figures with high resolution and reproducibility were obtained. Six differential expression proteins were found only in the serum from gastric cancer patients, while four other proteins from healthy volunteers.</p><p><b>CONCLUSIONS</b>Protein expression is differential in the serum from the gastric cancer patients and health volunteers. It is hopeful to find the biomarkers related with poorly differentiated gastric carcinoma using proteomics.</p>