The androgen-independent LNCaP (AIDL) cell line was generated by maintaining prostate cancer LNCaP cells in a hormone-deprived medium. Notably, synthetic androgen R1881-related gene response is attenuated in AIDL cells as compared to the parental LNCaP cells. The aim of this study was to clarify the mechanisms underlying androgen sensitivity in AIDL cells. We first examined the expression of androgen receptor (AR) and its co-regulators. However, no significant difference in mRNA expression was found between LNCaP and AIDL cells. Remarkably, AR protein levels were induced by R1881 and DHT in LNCaP cells, but not in AIDL cells. We next performed the cDNA sequencing to detect mutations in the AR gene. The T877A mutation was detected both in LNCaP and AIDL cells. Furthermore, AIDL cells harbored a missense substitution (TGG → TGT) in the AR gene, which caused a point mutation at codon 741 (W741C). Double T877A and W741C AR mutants have been previously reported to exhibit reduced androgen sensitivity. Hence, the low-androgen-sensitive responses of AIDL cells may be explained, at least in part, by AR gene mutations.
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This study was supported by a Grant-in-Aid from the Uehara Memorial Foundation and a Grant-in-Aid for Young Scientists (No. 21791514) from the Ministry of Education, Culture, Sports, Science, and Technology of Japan.
Huggins C, Hodges CV. Studies on prostatic cancer. I: The effect of castration, of estrogen and of androgen injection on serum phosphatases in metastatic carcinoma of the prostate. Cancer Res. 1941;1:293–7.Google Scholar
Suzuki H, Ueda T, Ichikawa T, Ito H. Androgen receptor involvement in the progression of prostate cancer. Endocr Relat Cancer. 2003;10:209–16.PubMedCrossRefGoogle Scholar
Thalmann GN, Anezinis PE, Chang SM, Zhau HE, Kim EE, Hopwood VL, et al. Androgen-independent cancer progression and bone metastasis in the LNCaP model of human prostate cancer. Cancer Res. 1994;54:2577–81.PubMedGoogle Scholar
Kokontis JM, Hay N, Liao S. Progression of LNCaP prostate tumor cells during androgen deprivation: hormone-independent growth, repression of proliferation by androgen, and role for p27Kip1 in androgen-induced cell cycle arrest. Mol Endocrinol. 1998;12:941–53.PubMedCrossRefGoogle Scholar
Hara T, Miyazaki J, Araki H, Yamaoka M, Kanzaki N, Kusaka M, et al. Novel mutations of androgen receptor: a possible mechanism of bicalutamide withdrawal syndrome. Cancer Res. 2003;63:149–53.PubMedGoogle Scholar
Ishikura N, Kawata H, Nishimoto A, Nakamura R, Ishii N, Aoki Y. Establishment and characterization of an androgen receptor-dependent, androgen-independent human prostate cancer cell line, LNCaP-CS10. Prostate. 2010;70:457–66.PubMedGoogle Scholar
Iguchi K, Ishii K, Nakano T, Otsuka T, Usui S, Sugimura Y, et al. Isolation and characterization of LNCaP sublines differing in hormone sensitivity. J Androl. 2007;28:670–8.PubMedCrossRefGoogle Scholar
Onishi T, Yamakawa K, Franco OE, Kawamura J, Watanabe M, Shiraishi T, et al. Mitogen-activated protein kinase pathway is involved in alpha6 integrin gene expression in androgen-independent prostate cancer cells: role of proximal Sp1 consensus sequence. Biochim Biophys Acta. 2001;1538:218–27.PubMedCrossRefGoogle Scholar
Iguchi K, Otsuka T, Usui S, Ishii K, Onishi T, Sugimura Y, et al. Zinc and metallothionein levels and expression of zinc transporters in androgen-independent subline of LNCaP cells. J Androl. 2004;25:154–61.PubMedGoogle Scholar
Ishii K, Imamura T, Iguchi K, Arase S, Yoshio Y, Arima K, et al. Evidence that androgen-independent stromal growth factor signals promote androgen-insensitive prostate cancer cell growth in vivo. Endocr Relat Cancer. 2009;16:415–28.PubMedCrossRefGoogle Scholar
Tepper CG, Boucher DL, Ryan PE, Ma AH, Xia L, Lee LF, et al. Characterization of a novel androgen receptor mutation in a relapsed CWR22 prostate cancer xenograft and cell line. Cancer Res. 2002;62:6606–14.PubMedGoogle Scholar
Rahman M, Miyamoto H, Chang C. Androgen receptor coregulators in prostate cancer: mechanisms and clinical implications. Clin Cancer Res. 2004;10:2208–19.PubMedCrossRefGoogle Scholar
Jaworski T. Degradation and beyond: control of androgen receptor activity by the proteasome system. Cell Mol Biol Lett. 2006;11:109–31.PubMedCrossRefGoogle Scholar
Tan J, Sharief Y, Hamil KG, Gregory CW, Zang DY, Sar M, et al. Dehydroepiandrosterone activates mutant androgen receptors expressed in the androgen-dependent human prostate cancer xenograft CWR22 and LNCaP cells. Mol Endocrinol. 1997;11:450–9.PubMedCrossRefGoogle Scholar
Gaddipati JP, McLeod DG, Heidenberg HB, Sesterhenn IA, Finger MJ, Moul JW, et al. Frequent detection of codon 877 mutation in the androgen receptor gene in advanced prostate cancers. Cancer Res. 1994;54:2861–4.PubMedGoogle Scholar
Taplin ME, Rajeshkumar B, Halabi S, Werner CP, Woda BA, Picus J, et al. Androgen receptor mutations in androgen-independent prostate cancer: Cancer and Leukemia Group B Study 9663. J Clin Oncol. 2003;21:2673–8.PubMedCrossRefGoogle Scholar
Urushibara M, Ishioka J, Hyochi N, Kihara K, Hara S, Singh P, et al. Effects of steroidal and non-steroidal antiandrogens on wild-type and mutant androgen receptors. Prostate. 2007;67:799–807.PubMedCrossRefGoogle Scholar
Gregory CW, He B, Johnson RT, Ford OH, Mohler JL, French FS, et al. A mechanism for androgen receptor-mediated prostate cancer recurrence after androgen deprivation therapy. Cancer Res. 2001;61:4315–9.PubMedGoogle Scholar
Sadar MD. Androgen-independent induction of prostate-specific antigen gene expression via cross-talk between the androgen receptor and protein kinase A signal transduction pathways. J Biol Chem. 1999;274:7777–83.PubMedCrossRefGoogle Scholar