5-Fluorouracil (5-FU) is a commonly used, effective anticancer drug.;To determine whether 5-FU induces apoptosis in our multistage model system composed of primary human ectocervical cells (HEC), HPV 18-immortalized HEC (HEC-18), and CSC-transformed HEC-18 cells (HEC-18T), we treated these cells with 5-FU.;The expression level of apoptosis-regulating proteins without treatment with apoptotic stimuli is known to correlate with the sensitivity of cells to apoptosis. To examine whether such a correlation exists in our model system for multistage cervical carcinogenesis, a panel of apoptosis regulating proteins was analyzed by Western blot analysis without 5-FU treatment.;To investigate whether the expression of apoptosis-regulating proteins is involved in the initiation of apoptosis induced by 5-FU treatment, a panel of such proteins was assayed by Western blot analysis in 5-FU-treated HEC-18 and HEC-18T grown in DMEM. Low-density lipoproteins (LDL) or elevated Ca 2+ concentration was employed to study the factors involved in the difference between susceptibility to apoptosis in KGM versus DMEM. (Abstract shortened by UMI.). |