[Study on antitumor drug-induced apoptosis in human cancer cells by terminal deoxynucleotidyl transferase assay].

Objective: Considerable evidence has showed that apoptosis is involved in both cancer development and inhibition. A new assay (terminal deoxynucleotidyl transferase assay, TdT assay) was recently reported to have advantages in the detection of apoptosis. In this study, this assay was used to investigate antitumor drug-induced apoptosis in human cancer cells.
Methods: TdT assay, DNA gel electrophoresis, electron and light microscopy were used to observe apoptosis.
Results: Our results showed that cisplatin-induced apoptosis in both HL-60 and SV40T-transformed human bronchial epithelial cells was detected with a good dose and time response. The occurrence of the apoptosis was preceded by the decrease of bcl-2 mRNA expression. With TdT assay, apoptotic cells were observed in the ovarian tumor of patients treated with carboplatin.
Conclusion: TdT assay may be applicable to moniter apoptosis in human cancers induced by chemotherapy, and to evaluate tumor cell response during treatment.