Unknown

Dataset Information

0

Regulation of the apoptosis-inducing kinase DRAK2 by cyclooxygenase-2 in colorectal cancer.


ABSTRACT:

Background

Cyclooxygenase-2 (COX-2) is over-expressed in colorectal cancer (CRC), rendering tumour cells resistant to apoptosis. Selective COX-2 inhibition is effective in CRC prevention, although having adverse cardiovascular effects, thus focus has shifted to downstream pathways.

Methods

Microarray experiments identified genes regulated by COX-2 in HCA7 CRC cells. In vitro and in vivo regulation of DRAK2 (DAP kinase-related apoptosis-inducing kinase 2 or STK17beta, an apoptosis-inducing kinase) by COX-2 was validated by qRT-PCR.

Results

Inhibition of COX-2 induced apoptosis and enhanced DRAK2 expression in HCA7 cells (4.4-fold increase at 4 h by qRT-PCR, P=0.001), an effect prevented by co-administration of PGE(2). DRAK2 levels were suppressed in a panel of human colorectal tumours (n=10) compared to normal mucosa, and showed inverse correlation with COX-2 expression (R=-0.68, R2=0.46, P=0.03). Administration of the selective COX-2 inhibitor rofecoxib to patients with CRC (n=5) induced DRAK2 expression in tumours (2.5-fold increase, P=0.01). In vitro silencing of DRAK2 by RNAi enhanced CRC cell survival following COX-2 inhibitor treatment.

Conclusion

DRAK2 is a serine-threonine kinase implicated in the regulation of apoptosis and is negatively regulated by COX-2 in vitro and in vivo, suggesting a novel mechanism for the effect of COX-2 on cancer cell survival.

SUBMITTER: Doherty GA 

PROVIDER: S-EPMC2720240 | biostudies-literature |

REPOSITORIES: biostudies-literature

Similar Datasets

| S-EPMC7593912 | biostudies-literature
| S-EPMC5929442 | biostudies-literature
| S-EPMC3096518 | biostudies-literature
| S-EPMC2709975 | biostudies-literature
| S-EPMC4516535 | biostudies-literature
| S-EPMC6124511 | biostudies-literature
| S-EPMC5564592 | biostudies-literature
| S-EPMC9845772 | biostudies-literature
| S-EPMC7453394 | biostudies-literature
| S-EPMC10837565 | biostudies-literature