The combination of docetaxel and the somatostatin analogue lanreotide on androgen-independent docetaxel-resistant prostate cancer: experimental data

OBJECTIVE

To evaluate the effects of the association between docetaxel and the somatostatin analogue lanreotide on the androgen‐independent prostate cancer cell line PC3, either sensitive or made resistant to docetaxel (PC3R), as new drugs and new combinations have promising clinical activity in hormone‐refractory prostate cancer.

MATERIALS AND METHODS

We examined the effect of docetaxel and lanreotide on cell proliferation, with analysis of the mitogen‐activated protein kinase pathway and expression of cell‐cycle regulatory proteins.

RESULTS

Combined treatment with docetaxel and lanreotide inhibited PC3 cell growth in vitro through an enhanced induction of cell death, compared with treatment with either agent alone; this result was particularly evident on PC3R cells. The results suggested that lanreotide could act as a P glycoprotein inhibitor in PC3R cells.

CONCLUSION

The present results provide a promising therapeutic approach for using somatostatin analogues in hormone‐refractory prostate cancer, in which lanreotide could interact with docetaxel in PC3R cells, with possible explanatory mechanisms which involve P glycoprotein‐mediated docetaxel resistance.