Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0376358 (prostate cancer)
 59,338 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The native PSA enhancer and promoter confer prostate-specific expression when inserted into adenovirus vectors capable of efficient in vivo gene delivery, although the transcriptional activity is low. By exploiting properties of the natural PSA control regions, we have improved the activity and specificity of the prostate-specific PSA enhancer for gene therapy and imaging applications. Previous studies have established that androgen receptor (AR) molecules bind cooperatively to AREs in the PSA enhancer core (-4326 to -3935) and act synergistically with AR bound to the proximal promoter to regulate transcriptional output. To exploit the synergistic nature of AR action we generated chimeric enhancer constructs by (1) insertion of four tandem copies of the proximal AREI element; (2) duplication of enhancer core; or (3) removal of intervening sequences (-3744 to -2855) between the enhancer and promoter. By comparing to the baseline construct, PSE, containing the PSA enhancer (-5322 to -2855) fused to the proximal promoter (-541 to +12), the three most efficacious chimeric constructs, PSE-BA (insertion of ARE4), PSE-BC (duplication of core) and PSE-BAC (insertion of core and ARE4), are 7.3-, 18.9-, and 9.4-fold higher, respectively. These chimeric PSA enhancer constructs are highly androgen inducible and retain a high degree of tissue discriminatory capability. Initial biochemical studies reveal that the augmented activity of the chimeric constructs in vivo correlates with their ability to recruit AR and critical co-activators in vitro. The enhanced activity, inducibility and specificity of the chimeric constructs are retained in an adenoviral vector (Ad-PSE-BC-luc). Systemic administration of Ad-PSE-BC-luc into SCID mice harboring the LAPC-9 human prostate cancer xenografts shows that this prostate specific vector retained tissue discriminatory capability compared with a comparable cytomegalovirus (CMV) promoter driven vector.
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PMID:Chimeric PSA enhancers exhibit augmented activity in prostate cancer gene therapy vectors. 1157 82

The proximal promoter of the kallikrein-related peptidase 3 gene (KLK3/PSA) contains a single-nucleotide polymorphism (G-158A) located within the second canonical half-site for the prostate-specific antigen (PSA) androgen response element 1 (AREI). Previous studies suggest that this polymorphism may be associated with higher PSA levels and increase prostate cancer risk. We have investigated the potential functional significance of this polymorphism and its association with prostate cancer susceptibility by genotyping the G-158A polymorphism in 209 men diagnosed with prostate cancer and 223 healthy control men in an Australian Caucasian population. Functional analyses of PSA AREI demonstrated that the A allele increased binding of AREI to the androgen receptor, as well as increasing transcriptional response to androgens. Association studies of the G-158A polymorphism demonstrated that men with an A/A genotype had a 3-fold increased risk for developing prostate cancer [95% confidence intervals (CIs) = 1.36-6.52] and men with an A/G genotype had a 2.4-fold increased risk (95% CIs = 1.23-4.81). Under a dominant model, the A allele conferred a 2.6-fold increased risk for prostate cancer (95% CIs = 1.37-4.96, P = 0.004). Taken together with the finding that the G-158A polymorphism is associated with an increased risk of prostate cancer in Australian men, our functional data suggest that the presence of the A allele in AREI may, in part, account for the altered PSA regulation seen in prostate cancer.
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PMID:PSA/KLK3 AREI promoter polymorphism alters androgen receptor binding and is associated with prostate cancer susceptibility. 1715 Oct 93