RESUMEN
Objective To study the effect of 5-lipoxygenase(5-LOX) inhibitor nordihyroguaiaretic acid (NDGA) combined the selective cyclooxygenase-2 (COX-2) inhibitor Celecoxib on the apoptosis of human colon carcinoma cell line HT-29. Methods Different concentration of NDGA and Celecoxib combinations were used to process cancer cell, and thiazolyl blue tetrazlium bromide (MTT) and phase contrast microscope and Annexin V/PI fluorescence staining and reverse transcription polymerase chain reaction (RT-PCR) were used to study the proliferation inhibited effect and apoptosis induced effect caused by combination of NDGA combined Celecoxib. Results MTT results showed that the viability of NDGA group, Celecoxib group and the group of NDGA combined Celecoxib (0.432±0.024,0.425±0.013,0.303±0.014 vs 0.693±0.018,t＝18.79,25.75,37.64,P＜0.01) was obviously lower than control group. The group of NDGA combined Celecoxib was significantly lower than NDGA group or Celecoxib group (t＝10.21, 14.14,P＜0.01). Under inverted phase contrast microscope, cell morphology significantly changed, and the group of NDGA combined Celecoxib changed most obviously. Apoptosis was observed by laser scanning confocal microscope (LSM) after NDGA and Celecoxib were used to process the HT-29. RT-PCR showed that up-regulation of Caspase-3 after treatment, and the combination of two drugs increased the most. Conclusions NDGA combined Celecoxib inhibited proliferation and induced apoptosis in human colon carcinoma cell line HT-29, and combined therapy had better effect than that of any drug used separate-ly. The mechanism may be associated with up-regulation of Caspase-3.