INDUCTION OF APOPTOSIS IN S-180 AND S-180R TUMOR CELLS BY ADRIAMYCIN IN VIVO

Apoptosis of tumor cells have become a new standard for chemotherapy. It is useful to demonstrate induction of apoptosis in tumor cells by anti-cancer drugs in vivo. We reported the results of apoptosis induction in murine tumor cell line S-180 and it's resistant cell line S-180R by adriamycin in different dose and different time. We found that apoptosis in S-180 cells could be induced by low dose of adriamycin, the apoptosis was started at 24 h. after the administration, and reached to 62.5% of the cells to apptosis until 72 h. Comparison with the parental cell line, only 13% of S-180R cells were apoptosed. At high dose, 20% of S-180R cells were apoptosed, whereas, almost all S-180 cells were killed in the same time. The lymphocytes were appeared in abdominal cavity of the mice after treatment of adriamycin for 24 h. It was very interested to find out that there was no lymphocyte left in the abdominal cavity of the mice with S-180R cells treated at high dose of adriamycin.

STUDY ON EFFECTS OF ARSENIC TRIOXIDE ON GASTRIC CANCER CELL LINES

Objective To evaluate the effects of arsenic trioxide (As-2O-3) on apoptosis and differentiation of gastric cancer cell lines (GCCL). Methods MKN45 and SGC7901 cells were treated with As-2O-3 at different concentrations, then the apoptosis rates and cell cycle were determined by flow cytometry assays, the morphologic changes were observed under fluorescence microscopy and electronic microscopy, and the gene expressions were tested with immunohistologic staining. Results Higher apoptosis rates of GCCL were seen in the As-2O-3-treated group at concentrations of 5μmol and 10μmol, as compared with those in the 5-Fu-treated group. Cell-nuclear pyknosis and chromosomal condensation were observed. The As-2O-3 at a concentration of 0.5 μmol could induce the cell cycle changes of GCCL, revealing an increase in the proportion of G1/G0 phase cells and a decrease in the proportion of S phase cells. From the fifth day after treatment of SGC7901 with As-2O-3 at a low concentration, P53 and bcl-XL genes expression rates were reduced, Bax gene expression rate increased, and bcl-2 gene expression showed little change. Conclusion As-2O-3 could induce GCCL apoptosis at a high concentration and differentiation at a low concentration, but it could not completely reverse the malignant biological behaviours of cancer cells.

Effects of arotinoid acid on induction of apoptosis and differentiation and telomerase activity and cell cycle in the HL 60 cell line

Objective To investigate the effects of arotinoid acid (Ro13 7410) on the morphological and functional alterations of leukemia HL 60 cell line and compared with those of RA Methods Differentiation of HL 60 cells was assessed by morphology and by NBT reduction Trypan blue exclusion was used to determine viability Apoptosis was assessed by changes in cell morphology and by measurement of fragmented DNA using the PCD assay kit Telomerase PCR ELISA kit tested telomerase activity The cell cycle was analyzed by flow cytometry Results Incubation of the HL 60 cells with 10 -6 10 -8 ?mol/L Ro13 7410 resulted in suppression of cell growth Apoptotic cells were detected following exposure to 10 -6 ?mol/LRo13 7410 for 3 hours by measurement of the “in situ” enzymatic labeling of DNA breaks with biotinylated dUTP Ultrastructural examination of Ro13 7410 treated samples showed cells with chromatin compaction and cytoplasm condensation and the presence of “apoptotic bodies” Cells induced into apoptosis were accompanied by Department of Hematology, the First Affiliated Hospital, Chongqing University of Medical Sciences, Chongqing 400016, China (Liu XS, Lou LS, Zeng SR and Tang ZH) Department of Clinical Biochemistry, Chongqing University of Medical Sciences, Chongqing 400046, China (Jiang JK, Zhang Y, Xu XG, Liu BZ, He YJ and Kang GF) increase of intracellular free Ca 2+ Percentage of HL 60 cells reduced NBT following incubation with Ro13 7410 was lower than with all trans retinoic acid (RA) (27% vas 85%) Telomerase PCR ELISA assay showed that HL 60 cells cultured in the absence of inducing agents had significant telomerase activity Telomerase activity declined gradually after 10 -6 ?mol/L Ro13 7410 treatment, and changes becoming evident at 1 day The inhibition of telomerase activity at day 5 of treatment with Ro13 7410 was less effective than with RA DNA flow cytofluorimetric analysis revealed that Ro13 7410 caused partial cell arrest in the G 2/M phase after a 2 day treatment and the percentage of cells arrested in the G 2/M phase increased after 4 days treatment With RA treated cells, a reduction in the percentage of cells in the G 2/M phase was observed after 2 day of treatment Conclusion Our study shows that Ro13 7410 suppresses HL 60 cells growth mainly via the induction of apoptosis and is less effective than RA in induction differentiation Ro13 7410 dramatically inhibits telomerase activity during the course of induction and results in G 2/M arrest within 2 days These findings suggest that Ro13 7410 is worthy of further study for its effects on leukemic cells

Xiaoji Decoction(消积饮) Inhibited Cell Proliferation and Induced Apoptosis through Akt Signaling Pathway in Human Lung Cancer A549 Cells

Objective： To investigate the inhibitive effect and the underlying mechanism of Xiaoji Decoction （消极饮 XJD） in human lung cancer A549 cells. Methods： A549 cells in logarithmic proliferation were cultivated in RPMI-1640 containing 10% low, medium or high dosages of XJD serum. The inhibitive effect of XJD in A549 cell proliferation was assessed by methylthiazolyldiphenyl-tetrazolium bromide （MTT） assay. The pro-apoptotic effect of XJD in A549 cells was observed by fluorescence microscope via Hoechst 33258 staining. The role of the Akt signaling pathway was observed by examining the presence of p-Akt protein by Western blot and the mRNA expression of downstream proteins such as Bcl-2/BcI-XL-associated death promoter （BAD） and caspase-9 by real time polymerase chain reaction. Results： MTT assay revealed that XJD could inhibit A549 proliferation in a dose- and time-dependent manner. Hoechst 33258 staining showed that XJD induced the typical nuclear apoptotic morphology after XJD treatment. Moreover, XJD could reduce the phosphorylation of Akt and increase the mRNA expression of BAD and caspase-9. Conclusions： XJD can inhibit the proliferation of A549 cells in a dose- and time-dependent manner through signaling Akt pathway via up-regulating the expression of BAD and caspase-9. XJD may provide a novel therapeutic model for lung cancer and deserve further study.