Sterling Kenneth M, Cutroneo Kenneth R
Dartmouth College, Department of Physics and Astronomy, 6127 Wilder Laboratory, Hanover, New Hampshire 03755-3528, USA.
J Cell Biochem. 2002;86(3):440-50. doi: 10.1002/jcb.10237.
Rat small intestinal epithelial cells and human colon adenocarcinoma cells cultured on Matrigel expressed the differentiation specific enzyme, sucrase-isomaltase, as determined by indirect immunofluorescence. Rat small intestinal epithelial cells, rat colonocytes, and human colon adenocarcinoma cells developed an altered morphology when cultured on Matrigel and became apoptotic within 24-48 h. Benzo[a]pyrene and 2,3,7,8-tetrachlorodibenzo-p-dioxin caused a 2- and 5-fold induction, respectively, of ethoxyresorufin-o-deethylase activity in rat small intestinal epithelial cells cultured on Matrigel. Benzo[a]pyrene- or 2,3,7,8-tetrachlorodibenzo-p-dioxin-induced ethoxyresorufin-o-deethylase activity in rat small intestinal epithelial cells cultured on plastic was not detected. 2,3,7,8-tetrachlorodibenzo-p-dioxin treatment caused a 14-fold induction of transfected, rat CYP1A1-promoter-luciferase activity in rat small intestinal epithelial cells cultured on Matrigel. Benzo[a]pyrene and 2,3,7,8-tetrachlorodibenzo-p-dioxin treatment induced ethoxyresorufin-o-deethylase activity by 6- and 1.6-fold, respectively in rat colonocytes cultured on Matrigel. Induction of ethoxyresorufin-o-deethylase activity was not observed in rat colonocytes cultured on plastic. CYP1A1-promoter-luciferase activity was induced 3-fold by 2,3,7,8-tetrachlorodibenzo-p-dioxin in rat colonocytes cultured on Matrigel. Induction of CYP1A1-promoter-luciferase activity in rat small intestinal epithelial cells or rat colonocytes cultured on plastic was not observed. Ethoxyresorufin-o-deethylase activity in human colon adenocarcinoma cells, cultured on either plastic or Matrigel, was induced 7-fold by benzo[a]pyrene. 2,3,7,8-Tetrachlorodibenzo-p-dioxin-induced ethoxyresorufin-o-deethylase activity was 2-fold greater in human colon adenocarcinoma cells cultured on Matrigel compared to cells cultured on plastic. Extracellular matrix-mediated differentiation and apoptosis of intestinal cells provide in vitro systems for study of the regulation of CYP1A1 expression, carcinogen activation in the gut and mechanism(s) of apoptosis of colon cancer cells.
通过间接免疫荧光法测定，在基质胶上培养的大鼠小肠上皮细胞和人结肠腺癌细胞表达了分化特异性酶——蔗糖酶-异麦芽糖酶。大鼠小肠上皮细胞、大鼠结肠细胞和人结肠腺癌细胞在基质胶上培养时形态发生改变，并在24 - 48小时内发生凋亡。苯并[a]芘和2,3,7,8-四氯二苯并对二恶英分别使在基质胶上培养的大鼠小肠上皮细胞中乙氧异吩唑酮-o-脱乙基酶活性诱导增加2倍和5倍。在塑料上培养的大鼠小肠上皮细胞中未检测到苯并[a]芘或2,3,7,8-四氯二苯并对二恶英诱导的乙氧异吩唑酮-o-脱乙基酶活性。2,3,7,8-四氯二苯并对二恶英处理使在基质胶上培养的大鼠小肠上皮细胞中转染的大鼠CYP1A1启动子-荧光素酶活性诱导增加14倍。苯并[a]芘和2,3,7,8-四氯二苯并对二恶英处理分别使在基质胶上培养的大鼠结肠细胞中乙氧异吩唑酮-o-脱乙基酶活性诱导增加6倍和1.6倍。在塑料上培养的大鼠结肠细胞中未观察到乙氧异吩唑酮-o-脱乙基酶活性的诱导。2,3,7,8-四氯二苯并对二恶英使在基质胶上培养的大鼠结肠细胞中CYP1A1启动子-荧光素酶活性诱导增加3倍。在塑料上培养的大鼠小肠上皮细胞或大鼠结肠细胞中未观察到CYP1A1启动子-荧光素酶活性的诱导。苯并[a]芘使在塑料或基质胶上培养的人结肠腺癌细胞中乙氧异吩唑酮-o-脱乙基酶活性诱导增加7倍。与在塑料上培养的细胞相比，2,3,7,8-四氯二苯并对二恶英诱导的乙氧异吩唑酮-o-脱乙基酶活性在基质胶上培养的人结肠腺癌细胞中高2倍。细胞外基质介导的肠道细胞分化和凋亡为研究CYP1A1表达的调控、肠道中致癌物的激活以及结肠癌细胞凋亡的机制提供了体外系统。
