Current status of chemotherapy sensitivity testing for urological malignancies

Growth characteristics of early passage cell lines compared with established TCC bladder lines

The growth patterns of established cell lines from bladder transitional cell carcinoma (TCC) were compared with early passage cell lines. The growth of established cell line 5637 was uninhibited in both serum free (basal) and serum containing media. The early passage line (DR) grew only in serum containing medium. This confirms the unreliability of results from biological studies on established (continuous) cell lines.

Comparative study of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and tritiated thymidine in a chemosensitivity test using collagen gel matrix

An organ culture system using collagen gel matrix (CGM) was modified and established successfully as a rapid and convenient method for determination of anti-cancer drug sensitivities. The cell viability of a tumor fragment was measured by the reduction of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) to a colored formazan product, which allowed for quantitative and simple analysis. The sensitivities of KK-47 bladder tumor from nude mice to various anti-cancer drugs tested corresponded closely to those determined in the original CGM assay system using tritiated thymidine, which has a high clinical correlation. Our modified method can be used as a practical and highly reproducible chemosensitivity test in vitro.

Cultured human bladder tumors for pharmacodynamic studies

Human bladder tumor fragments were cultured on collagen gel. In this system, the three dimensional architecture, cell-to-stroma and cell-to-cell interactions, and tumor heterogeneity were maintained. Cell viability and labeling index (LI) were determined by exposure to 3H-thymidine and autoradiography. Of the samples from 20 patients with transitional cell carcinoma, 14 (70%) were successfully cultured and had a mean LI of 32%. In addition, one specimen from a patient with squamous cell carcinoma was cultured and had a LI of 61%. Cultured samples were tested for chemosensitivity using a two hour exposure of mitomycin C in concentrations ranging from one to 50 micrograms./ml. A dose-dependent relationship was demonstrated; LI decreased as mitomycin C concentrations increased. The methodology described provides an alternative to suspension or monolayer techniques of culturing human bladder tumors for pharmacological studies.

Clonal growth requirements of human bladder tumor cell lines

We have serially investigated the role of nutrients and growth factors for their ability to support the clonal growth of human bladder tumor cell lines. Five established human bladder tumor cell lines were selected for study of their requirements for clonogenic growth in semisolid cultures. We identified an "optimal medium" to be Alpha MEM medium, 15% horse serum, five micrograms/ml. of transferrin, five micrograms/ml. of insulin and 30 ng./ml. of epidermal growth factor. The "optimal assay" enhanced the growth of human bladder tumor cell lines 2.5 times compared to the standard clonogenic assay. The resulting medium is less complicated to maintain, less expensive and supports the growth of human bladder tumor cell lines better than the standard clonogenic assay.

Assessment of human genitourinary tumors and chemosensitivity testing in 3-dimensional collagen gel culture

A recently described collagen gel culture technique has been modified to evaluate the growth characteristics and chemosensitivity patterns of genitourinary neoplasms. Fresh human surgical explants incorporated radiolabeled DNA precursors [H3)thymidine or deoxyuridine) in 97% of 38 patient specimens (18/19 bladder, 3/3 prostate, 2/2 testis, 13/14 renal), after being maintained for three to 13 weeks/passage, with several specimens reaching their sixth passage (20 months). Control cellular DNA incorporation ranged from five to 90% (#cells labeled/#cells evaluated), with median labeling for bladder 30%, prostate 80%, testis 90%, and renal 80%. Original histopathologic classification was maintained in all cases. Tumor volume and glucose consumption were other measurable parameters. Seventy-three surgical specimen cultures were treated with chemotherapeutic agents after a minimum of four weeks in culture. Single agent exposures were 24 hours at 1X and 10X reported peak plasma concentrations. Combination agents were sequenced as in current clinical protocol for bladder tumors and fourteen day continuous fluorodeoxyuridine (FdURD) exposure for renal tumors. Sensitivity was found in 1/2 prostate and 1/10 renal tumors to Adriamycin, 8/15 bladder and 1/2 testis tumors to cisplatin, 11/28 renal tumors to FdURD and 6/16 bladder tumors to MVAC combination chemotherapy. This culture system offers the advantages of in vivo-like solid tumor growth, a high culture success rate, longevity in culture, maintenance of the primary histopathology and reproducible chemosensitivity response.

Clonal growth of bladder cancer cells in a double layer soft agar assay: needles addition of multiple culture supplements

The necessity of multiple culture supplements, characteristic of Hamburger and Salmon (H&S) soft agar assay (1977), for the clonal growth of bladder cancer cells was systematically investigated. One murine and 6 human cell lines were cultivated in different culture supplemented conditions based on the H&S method. All cell lines successfully formed colonies in the absence of supplements. The inclusion of 2-mercaptoethanol to supplement-free medium stimulated the clonal growth of murine (MBT-2) cells, whereas it did not affect the growth of human cell lines. DEAE-dextran suppressed the clonal growth of 5 out of 7 lines. Tryptic soy broth stimulated the growth of 2 human cell lines, whereas it suppressed the other 2 cell lines. The chemosensitivity of MBT-2 cells was not affected by these supplements.

Human renal cell carcinoma in the six day subrenal capsule assay

The applicability of the subrenal capsule assay (SRCA) as a method for chemosensitivity testing of human renal cell carcinoma (RCC) was assessed. Tissue fragments of about one mm3. in size, obtained from patients who had undergone nephrectomy because of renal cell carcinoma (RCC), were implanted in preirradiated mice. The change of the size of the implanted tissue as well as the histology of the tissue were determined six days later. Untreated control tumors were used to determine the evaluability of the individual assays using criteria based on 1) tumor growth (an increase in tumor size or a decrease not exceeding 0.05 mm.) and 2) tumor histology (presence of carcinoma cells in at least 70% of the tissues). The first criterion was fulfilled in 20/24 (83%) of the renal tumors; tumor histology was satisfactory in 9/24 (38%) of the tumors. Taken together, only 9/24 assays were considered to be evaluable. Discrepancies between measurement and histologic appearance were also found for individual tumors and for treated tumors. Due to the lack of correlation between measurement and histology change in tumor size therefore cannot be considered a reliable parameter for assessing viability or drug activity.