The Use of Early Sea Urchin Embryos in Anticancer Drug Testing

In vitro anticancer drug testing is routinely performed on cell lines established from various types of malignant tumors. The use of these cell models has proved effective in determining the worthiness of potential drugs for further testing at the clinical level. They provide a system in which a potential drug may be added to a living culture of tumor cells and the drug’s effects on cell proliferation and/or more specific mitotic events may be determined. However, in order for the effectiveness of a drug to be determined, it must be tested in some instances over many cell generations. It is particularly important for telomerase- and telomere-interactive drugs whose effects on telomere shortening may become apparent only after many cell cycles. This need for accurate testing carries with it certain operational problems, all related to the fact that cell generation times may be prolonged up to 24 h in some tumor cell lines: (1) the cell culture medium becomes depleted of nutrients over several cell cycles and must be replaced regularly; (2) the drug must also be replaced when the culture medium is replaced; (3) the drug may degrade over prolonged periods in culture and may need to be replaced more often than medium changes; (4) the elevated temperature (37�C) may accelerate drug breakdown; (5) the time and expense of maintaining the cells and drugs over a sufficient number of cell cycles for reliable drug testing is considerable; and (6) there are no convenient internal markers for cell viability separate from the cell proliferation and chromosomal effects that are already being determined.