References

Notes: The cisplatin (CDDP)-resistant subline TYK-nu (R) was developed by culturing TYK-nu (human ovarian cancer cell line in vitro) with exposure to CDDP in stepwise increasing concentrations. The characteristics of both cell lines were compared and the results were as follows; 1. Both cell lines formed a monolayer in a pavement-like arrangement and large cells were occasionally present in TYK-nu (R) rather than TYK-nu. The population doubling time of TYK-nu and TYK-nu (R) was 43hr and 48hr, respectively. 2. IC_<50> ƒÊg/ml) in 96hr treatment with CDDP and carboplatin (CBDCA) was 0.035 and 0.5 in TYK-nu and 0.62 and 2.0 in TYK-nu (R), respectively. 3. In the intracellular CDDP concentration, there was no marked difference between TYK-nu and TYK-nu (R) after CDDP (2.0ƒÊ/ml) treatment in 2hr. 4. After treatment with CDDP (0.2ƒÊg/ml) or CBDCA (2.0ƒÊg/ml), a decrease in S and G2+M compartments was observed in the pattern of the DNA histogram of TYK-nu, but not in that of TYK-nu (R). 5. The majority of chromosomes in both cell lines were in hyperdiploid areas and the mode of TYK-nu and TYK-nu (R) was 56 and 51, respectively. The karyotype of TYK-nu (R) showed deletion of chromosome 7q. Thus, compared to TYK-nu, TYK-nu (R) was 17.7 times more resistant to CDDP and 4 times more resistant to CBDCA. The results suggest that the mechanism of resistance to CDDP may be due to genetic changes at the cellular level.
Reference ID: 6265

Notes: A new ovarian cancer cell line has been established from the dispersed cells taken from a heterotransplanted tumor at the 6th passage in nude mice which had been serially transplanted with a primary lesion of undifferentiated carcinoma (FIGO) of the ovary. Selection of cancerous epithelioid cells was completed by the 4th passage by means of the colonial cloning method. The cell line designated TYK-nu was subcultured serially in Eagle's MEM with 10% FCS more than 100 times over 31 months at March, 1986 and was observed to produce a tumor on implantation into nude mice histologically similar to the original tumor. These cells form a monolayer in a pavement-like arrangement with polygonal cells including giant cells and reveal a lack of contact inhibition. PAS positive substance can be seen in the cytoplasm. Desmosome structure, well-developed cell organelles and glycogen granules can be found by electron microscopy. The population doubling time was about 37 hours and the plating efficiency was 13-17%. All cells were seen to be of the human karyotype on chromosomal analysis and the number of chromosome in the majority of cells was hyperdiploidy with a mode of 56 at the 6th and 84th passages. A submetacentric marker chromosome was present. Using in vitro colony assay, TYK-nu was studied for drug sensitivity to cisplatin, adriamycin, vincristine, 5-fluorouracil and etoposide, and found to be sensitive to cisplatin
Reference ID: 2568

Reference ID: 2685