| Apoptosis is one of the most important life phenomena. Both inadequacy and excess of apoptosis are related to many serious diseases, such as cancer and neurodegenerative disorders. During researching on the relationship between apoptosis and tumor, most attention was paid to morphologic and biochemical changes and genetic control of apoptotic cells. It is found in the latest researches that mitochondria are not only energy-producing center, but also the apoptosis-inducting center in mammalia. The report on major roles of mitochondria during apoptosis in esophageal carcinoma has not been seen in the literature. To make it clear, using multilaser flow cytometry, molecular biologic technology and laser confocal microscope scan technology, we fixed eyes on mitochondrial permeability transition pores(MPTP), mitochondrial transmembrane potential(Δ ψm) and caspases-3 (cysteinyl aspartate-specific proteinases) which are playing key roles of mitochondria. Meanwhile, the research also discussed the characteristics of Δ ψm of cells in cut specimenfrom esophageal carcinoma, adjacent tissue of esophageal carcinoma and the normal esophageal tissue. The major aim is to find mitochondrial specific roles of inducting apoptosis in esophageal carcinoma, and to provide theoretical basis for designing lipophilic mitochondria-target anti-cancer drugs. The article consists of three parts. Part I: Alteration of Δ ψm in apoptotic cells of carcinoma of esophagusIn order to elucidate event mentioned above, we have used mitochondrial transmembrane potential ( Δ ψm ) specific fluorescent probes JC-1 (5,5',6,6'-tetrachloro-l,r,3,3'-tetraethylbenzimidazol carbocyamine), to label EC9706 cells, combined flow cytometry in the process of irradiation and chemotherapy inducing apoptosis to deserve the changes of Δ ψm . Using CsA(Cyclosporin A), an inhibitor of MPTP, we have studied the change trend of A V m and in the meanwhile, the early apoptosis was detected by PS(Phosphatidylserine) exposing marker.Results:1. Treated with CP(Cisplatin) in different concentration: 15 V- g/ml, 30 14 g/ml,6014 g/ml. The quantity of early cellular apoptosis obviously increased, 24h after CP 3014 g/ml, in contrast to control group treated with no CP, statistic difference was significant (P<0.01) ; the similar result was obtained 16h after CP 60 y g/ml (P<0.001). It demonstrates that CP of the above concentration can induce cellular apoptosis certainly.2.12h after treatment with 15Gy, 20Gy, 30Gy irradiation, although obvious increase of early cellular apoptosis did not occur, cellular death by apoptosis obviously increased. In contrast to control group treated with no irradiation, after treatment with 30Gy irradiation, There was significant difference (PO.001).3.JC-1 labelling Δ ψm will fluoresce. Red fluorescence represents high potential and green fluorescence represents low potential. 20h after CP 3014 g/ml, red fluorescence declined obviously(P<0.001), but green fluorescencechanged less(P<0.05). lOh after CP 60 u g/ml, red fluorescence obviously10declined; 24 h, not only red fluorescence but also green fluorescence declined (P<0.001).4. 10h incubation after irradiation in the former dose, red fluorescence declined as the increase of irradiating dose. Green one changed less. In contrast to control group treated with no irradiation, 10h incubation after treatment with 30Gy irradiation, statistic difference of both red and green fluorescence was highly significant (P<0.001).5. After MPTP was inhibited, 24 h after CP 30 n g/ml, the proportion of early apoptosis altered little (P<0.001). Furthermore, in the same condition, the red fluorescence of JC-1 labeled Δ ψm declined less than that before MPTP was inhibited. 20h after treatment with CP30 J4 g/ml the intensity of red fluorescence changed significantly (P<0.001). Even at this time, Δ ψm was still on middle state after MPTP was inhibited.Part II: Caspase-3 mRNA, Caspase-3 protein expression and relatedtargets during apoptosis of esophageal carcinoma...
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