Trial Information

Correlation of the Microculture Kinetic (MiCK) Apoptosis Test Results With Drug Treatment Results in Cancer Patients

Identification of those patients with cancer who will or will not respond to a specific
chemotherapy is important for making decisions regarding chemotherapy regimens as well as
alternative management approaches. A laboratory test that could help to determine the
sensitivity of an individual patient's tumor cells to specific chemotherapeutic agents would
be valuable in choosing the optimal chemotherapy regimen for that patient with an
expectation of increasing the response rate to the therapy. Several types of in vitro
assays that measure tumor cell survival following exposure to cytotoxic agents have been
evaluated for their ability to predict chemotherapy outcomes. As a group, these assays are
referred to as drug resistance assays. In a resistance assay, the surviving tumor cells can
be detected directly by their exclusion or metabolism of specific dyes. Alternatively,
since some of tumor cells are proliferating, their survival can be detected by measurement
of DNA synthesis by radiolabeled precursor incorporation or demonstration of clonogenic
potential by growth into colonies in semi-solid culture medium. In several clinical studies,
these assays were useful in detecting drug resistance and in predicting a poor prognosis for
cancer patients. However, these resistance assays cannot detect sensitivity of an individual
patient's tumor cells to a specific drug. Therefore, new methods determining
drug-sensitivity of the tumor cells of an individual patient and, thus, capable of both
predicting a positive treatment outcome and guiding chemotherapy, would be of significant
value.

Recently, an automated microculture kinetic (MiCK) assay for measuring drug induced
apoptosis in tumor cells has been developed1-4. Apoptosis is a distinct mode of cell death
which occurs under physiological conditions and yet can be induced in malignant cells by
chemical and physical factors including antitumor drugs5-7. During the last decade, it has
been recognized that chemotherapeutic agents exert their antitumor activity by triggering
apoptosis in susceptible tumor cells8-17. This implies that the MiCK assay for apoptosis
provides a mechanism-based approach to studying effects of cytotoxic agents on tumor cells.
Unlike "resistance" assays that measure a fraction of cells surviving drug exposure, the
MiCK assay measures a fraction of tumor cells killed by a chemotherapeutic agent via
mechanism of apoptosis. Therefore the MiCK assay determines drug sensitivity, rather than
resistance. Recently the MiCK assay has been shown to predict complete remission rate and
survival in acute myeloid leukemia patients better than clinical criteria did18-20. In a
limited study, the MiCK assay has been used to direct chemotherapy of the leukemia patients
21.

The MiCK assay has also been used to study drug-induced apoptosis in solid tumors, including
neuroblastoma and colon adenocarcinoma cell lines22-23. More recent data accumulated by
DiaTech has demonstrated that the MiCK assay can detect drug induced apoptosis in primary
cultures of tumor cells isolated from patients with ovarian carcinoma, gastric carcinoma,
metastatic breast cancer and high grade soft tissue sarcoma. The purpose of this study is to
correlate the results of the MICK assay with short- and long-term results of treatments in
cancer patients and evaluate the role of the MiCK assay in guiding chemotherapy of cancer
patients.