Home Blog of Signal Transduction Metabolism HMG-CoA Reductase Androgen Deprivation Followed by Acute Androgen Stimulation Selectively Sensitizes AR-Positive Prostate Cancer Cells to Ionizing Radiation

Category

Archives

Popular Post

ESKM, a novel therapeutic agent for sensitive and resistant PH+ leukemias

The mechanism of resistance to JAK2 inhibitor in myeloproliferative neoplasms patients

Effects of PARP inhibitors in BRCA gene-mutated ovarian cancer

DASATINIB; An inhibitor of Receptor Tyrosine Kinase

GP130/JAK/STAT3 signaling pathway induces multiple myeloma

Androgen Deprivation Followed by Acute Androgen Stimulation Selectively Sensitizes AR-Positive Prostate Cancer Cells to Ionizing Radiation

PURPOSE:

The current standard of care for patients with locally advanced prostate cancer is a combination of androgen deprivation and radiation therapy. Radiation is typically given with androgen suppression when testosterone levels are at their nadir. Recent reports have shown that androgen stimulation of androgen-deprived prostate cancer cells leads to formation of double-strand breaks (DSB). Here, we exploit this finding and investigate the extent and timing of androgen-induced DSBs and their effect on tumor growth following androgen stimulation in combination with ionizing radiation (IR).

EXPERIMENTAL DESIGN:

Androgen-induced DNA damage was assessed by comet assays and γH2A.X foci formation. Effects of androgen stimulation and radiation were determined in vitro and in vivo with xenograft models.

RESULTS:

We document that androgen treatment of androgen-deprived prostate cancer cell lines resulted in a dose- and time-dependent induction of widespread DSBs. Generation of these breaks was dependent on androgen receptor and topoisomerase II beta but not on cell-cycle progression. In vitro models demonstrated a synergistic interaction between IR and androgen stimulation when IR is given at a time point corresponding with high levels of androgen-induced DSB formation. Furthermore, in vivo studies showed a significant improvement in tumor growth delay when radiation was given shortly after androgen repletion in castrated mice.

CONCLUSIONS:

These results suggest a potential cooperative effect and improved tumor growth delay with androgen-induced DSBs and radiation with implications for improving the therapeutic index of prostate cancer radiation therapy. 

Related Products

Cat.No. Product Name Information
S2061 Lovastatin Lovastatin is an inhibitor of HMG-CoA reductase with IC50 of 3.4 nM in a cell-free assay, used for lowering cholesterol (hypolipidemic agent). Lovastatin triggers autophagy.

Related Targets

HMG-CoA Reductase