Morphological Change with the Induction of Cisplatin Resistance from the Bladder Cell Lines

Yoon, Sang Jin; Lee, Eun Sik

Abstract

PURPOSE: When Managing metastatic bladder tumors, to overcome the resistance mechanism of cisplatin is a main problem to be solved. The objective is to confirm the changes of general and ultrastructural morph ology with the induction of cisplatin resistance from the bladder cell line.
MATERIALS AND METHODS
The samples of this investigation are 2ng/ml-cisplatin resistant human bladder cell lines T24R2 established by SNUH Urology and the drug resistant bladder cell lines T24 was obtained from ATCC, as a control group. We cultured the resistant cell line on the slide and observed it using light microscopy to see the general morphology. For the ultrastructural morphology, we fixed cultured cells, made an epon block, sliced an ultrathin section and observed it using H-71000 EM.
RESULTS
Under light microscopy, the cytoplasm of the resistant cell line shows a plumper pattern than that of the parent cell. Under electronmicroscopy, the chromatin of the resistant cell line has a relatively finely dispersed chromatin pattern when compared to the parent cell line, which shows a coarse and aggregated chromatin pattern. Within the cytoplasm, the mitochondrial volume, dilated rough endoplasmic reticulum, polyribosomes and ribosomes are moderately increased in the resistant cell line when compared to the parent cell line. In particular, we found a great amount of double membrane vesicle near the cell surface and pinocytic vesicles on the surface, which are seldom observed within the parent cells.
CONCLUSIONS
We concluded that the cisplatin resistant human bladder cell lines (T24R2) underwent a morphological change with the induction of cisplatin resistance, and we hypothesize that the resistant cell's ultrastructure, which shows morphological change, will be involved in the drug resistance mechanism. Regarding this matter, further research will be needed.