Cheon Chan Woo, Kim Dae Hwan, Kim Dong Heon, Cho Yong Hoon, Kim Jae Hun
Department of Surgery, Medical Research Institute, Pusan National University, Busan, South Korea.
World J Gastroenterol. 2009 Jan 21;15(3):310-20. doi: 10.3748/wjg.15.310.
To determine the cytological and molecular effects of peroxisome proliferation-activated receptor (PPAR)-gamma and PPAR-gamma agonists on stomach cancer cells.
To determine the proliferation-suppressive effects of troglitazone and ciglitazone, SNU-216 and SNU-668 stomach cancer cells were plated in media containing 40 micromol/L troglitazone and ciglitazone at a density of 1 multiply 10(4) cells/well. After 3, 5 and 7 d, the cells were counted with a hemocytometer. To assess the appearance of PPAR-gamma, a reverse-transcription polymerase chain reaction analysis was performed. On day 7, Western blotting was used to determine the effects of troglitazone and ciglitazone on the expression of p21 and phosphorylated-ERK (pERK) genes. Flow cytometry analysis was used to determine which portion of the cell cycle was delayed when troglitazone was used to suppress cell proliferation. In order to clarify the mechanism underlying the activity of troglitazone, microarray analysis was conducted.
PPAR-gamma was manifested in both SNU-216 and SNU-668 cells. Ciglitazone and troglitazone suppressed cell growth, and troglitazone was a stronger suppressor of stomach cancer cells than ciglitazone, an inducer of cell cycle arrest in the G1 phase. SNU-668 cells were also determined to be more sensitive to ciglitazone and troglitazone than SNU-216 cells. When troglitazone and ciglitazone were administered to stomach cancer cells, levels of p21 expression were increased, but ERK phosphorylation levels were reduced. When GW9662, an antagonist of PPAR-gamma, was applied in conjunction with ciglitazone and troglitazone, the cell growth suppression effect was unaffected. The gene transcription program revealed a variety of alterations as the consequence of troglitazone treatment, and multiple troglitazone-associated pathways were detected. The genes whose expression was increased by troglitazone treatment were associated with cell development, differentiation, signal transmission between cells, and cell adhesion, and were also associated with reductions in cell proliferation, the cell cycle, nuclear metabolism, and phosphorylation.
Troglitazone and ciglitazone suppress the proliferation of stomach cancer cells via a PPAR-gamma-independent pathway.
确定过氧化物酶体增殖激活受体（PPAR）-γ及PPAR-γ激动剂对胃癌细胞的细胞学和分子效应。
为确定曲格列酮和环格列酮的增殖抑制作用，将SNU-216和SNU-668胃癌细胞以1×10⁴个细胞/孔的密度接种于含有40μmol/L曲格列酮和环格列酮的培养基中。3、5和7天后，用血细胞计数器对细胞进行计数。为评估PPAR-γ的表达情况，进行逆转录聚合酶链反应分析。在第7天，采用蛋白质印迹法确定曲格列酮和环格列酮对p21和磷酸化细胞外信号调节激酶（pERK）基因表达的影响。采用流式细胞术分析来确定当使用曲格列酮抑制细胞增殖时，细胞周期的哪一部分被延迟。为阐明曲格列酮活性的潜在机制，进行了基因芯片分析。
PPAR-γ在SNU-216和SNU-668细胞中均有表达。环格列酮和曲格列酮抑制细胞生长，且曲格列酮对胃癌细胞的抑制作用强于环格列酮，可诱导细胞周期停滞于G1期。还确定SNU-668细胞比SNU-216细胞对环格列酮和曲格列酮更敏感。当将曲格列酮和环格列酮应用于胃癌细胞时，p21表达水平升高，但ERK磷酸化水平降低。当PPAR-γ拮抗剂GW9662与环格列酮和曲格列酮联合应用时，细胞生长抑制作用未受影响。基因转录程序显示，曲格列酮处理后出现了多种改变，并检测到多个与曲格列酮相关的信号通路。经曲格列酮处理后表达增加的基因与细胞发育、分化、细胞间信号传递及细胞黏附相关，也与细胞增殖、细胞周期、核代谢及磷酸化的减少相关。
曲格列酮和环格列酮通过一条不依赖PPAR-γ的途径抑制胃癌细胞的增殖。
