In vitro testing of platinum-based drugs on a panel of human ovarian tumour cell lines

Much improvement in the treatment of ovarian cancer has been achieved since the introduction of platinum compounds in the 1980s, with the result that single-agent platinum-based therapy following primary surgery is now the standard treatment for advanced ovarian cancer. The main therapeutic effect of chemotherapy is based on the sensitivity of the patient's tumour to the drug. However, testing a new chemical compound on humans requires much care, time and resources, whereas prior testing of drugs on cancer cell lines may indicate those drugs particularly suited to treatment of a specific disease. This study investigates the actions of two established platinum-based chemotherapeutic agents (cisplatin and carboplatin) on a panel of 10 human ovarian cancer cell lines. Each cell line was plated onto 96-well tissue culture plates, incubated for 72 hours with the drug, formalin-fixed and then assessed using the methylene blue colorimetric microassay to detect viable cells. The IC50 values for each cell line were calculated in order to assess the toxicity of each drug, and a wide range of responses were observed across the 10 cell lines investigated. This suggests that the panel reflected the heterogeneous nature of ovarian cancer, a malignancy in which a huge range of drug sensitivities can be seen even among tumours of the same histological type. The results indicate that the panel could be of use either as a primary screen to test new drugs against ovarian cancer or to investigate the drug resistance that is so common in this disease.