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OBJECTIVE To explore whether overexpression of human telomerase re-verse transcriptase (hTERT) in Raji cells can protect against etoposide (VP-16)-induced apoptosis.METHODS A lipofectin-mediated gene transfection method was used to transfer the hTERT gene into Raji cells. The polymerase chain reaction enzyme-linked immunoassay was employed to determine telomerase activity.The expression levels of hTERT protein were assayed by immunofluorescence using a fluoresce isothiocyanate label. Cell viability was determined using the trypan blue dye exclusion assay. Apoptosis was assessed by morphological observation and flow cytometry analysis.RESULTS The results showed that there was a marked increase in both mean fluorescence intensity of hTERT-protein-positive cells and telomerase activity in hTERT- transfected Raji cells (P ＜0.05), but there was no difference in hTERT protein and telomerase activity levels between Raji cells and vectortransfected Raji cells (P ＞0.05). There were more viable cells at 48 h and 72 h after treatment of hTERT-transfected Raji cells with 10 μmol/L VP-16 compared to either vector-transfected Raji cells and Raji cells (P ＜0.05). Apoptosis rates at 72 h after treatment with 10 μmol/L VP-16 were 4.34 ±1.03% in hTERT-transfected Raji cells, 33.21 ± 3.12% in vector-transfected Raji cells,and 31.63 ± 3.06% in Raji ceils. There was a significant difference in the percentage of apoptotic cells between hTERT-transfected Raji cells and either vector-transfected Raji cells or Raji cells (P＜0.05).CONCLUSION Overexpression of telomerase by transfection of hTERT gene can protect against etoposide-induced apoptosis in Raji cells.