837 860
[(Fig._1)TD$FIG]
Fig. 1 – Enzalutamide (Enz) treatment results in higher expression of the androgen receptor splicing variant 7 (AR-v7) and
Malat1
. (A) AR-v7 expression
is higher in Enz resistant cell lines (R1 and R2) compared with parental (P) cells, using Western blotting to measure full length androgen receptor (AR-
FL) and AR-v7 with AR-N20 and AR-v7 specific antibody, respectively, while glyceraldehyde 3-phosphate dehydrogenase (GAPDH) was used as a loading
control. (B) The quantitative polymerase chain reaction (qPCR) analysis suggests
Malat1
(right) and AR-v7 messenger RNA (left) were dramatically
increased after cells acquired Enz resistance. (C) Cartoon showing transcription activator-like effector (TALE) targeting sites on the
Malat1
promoter.
(D) TALE-based transactivation induces
Malat1
. Left,
Malat1
expression after TALE-based transcription factors were transduced into C4-2 cells. Right,
AR-FL and AR-v7 were detected by western blotting in two cell populations infected with
Malat1
inducers. (E) AR variants were detected by qPCR in
two
Malat1
-inducers-infected cells. (F)
Malat1
-expressing cells showed AR-v7 gene signature. Cell cycle genes regulated by AR-v7 were tested with
qPCR in
Malat1
-expressing cells that were induced by TALE expression. (G) The short interfering
Malat1
(si
Malat1
) reversed the induced expression of
AR-v7 target genes in cell lines. (H)
Malat1
, AR-v7, and AR-FL expression in circulating tumor cells of metastatic castration-resistant prostate cancer
patients before (Pre-Enz) and after (Post-Enz) Enz treatment (
n
= 10).
*
p
< 0.05.
**
p
< 0.01.
***
p
< 0.001.
E U R O P E A N U R O L O G Y 7 2 ( 2 0 1 7 ) 8 3 5 – 8 4 4
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