Korean J Urol.  2013 Jun;54(6):404-408.

Is the Expression of Androgen Receptor Protein Associated With the Length of AC Repeats in the Type III 5-alpha Reductase Gene in Prostate Cancer Patients?

• Park JM
• Song KH
• Lim JS
• Kim JW
• Sul CK

Abstract

PURPOSE
Type III 5-alpha reductase (SRD5A3; steroid 5-alpha reductase 3) may be associated with the progression of prostate cancer (PCa). The aim of our study was to determine whether the length of AC repeats in the SRD5A3 gene is associated with the risk of PCa and the expression of androgen receptor (AR) protein in Korean men.
MATERIALS AND METHODS
We compared the length of AC repeats in the short tandem repeat (STR) region of the SRD5A3 gene in 68 PCa patients and 81 control subjects by genotyping. A total of 55 patients in the PCa group underwent radical prostatectomy. We evaluated the expression of AR protein by using Western blotting and tested the association between the type of AC repeats in the SRD5A3 gene and AR protein expression and clinical and pathologic parameters.
RESULTS
The short type of STR had less than 21 copies of AC repeats in the SRD5A3 gene. The SS type (short and short type) of STR of the SRD5A3 gene was 2.2 times as likely to occur in PCa patients as in controls (odds ratio, 2.21; 95% confidence interval, 1.14 to 4.31; p=0.019). However, AC repeats of the SRD5A3 gene were not associated with AR protein expression or clinical or pathologic parameters in PCa samples.
CONCLUSIONS
These results suggest that the short AC repeats of SRD5A3 polymorphism are associated with an increased risk of PCa. SRD5A3 polymorphism may contribute to a genetic predisposition for PCa.

Keyword

3-Oxo-5-alpha-Steroid 4-Dehydrogenase; Androgen receptors; Genetic polymorphism; Prostatic neoplasms

MeSH Terms

3-Oxo-5-alpha-Steroid 4-Dehydrogenase
Blotting, Western
Coat Protein Complex I
Genetic Predisposition to Disease
Humans
Microsatellite Repeats
Oxidoreductases
Passive Cutaneous Anaphylaxis
Polymorphism, Genetic
Prostate
Prostatectomy
Prostatic Neoplasms
Receptors, Androgen
3-Oxo-5-alpha-Steroid 4-Dehydrogenase
Coat Protein Complex I
Oxidoreductases
Receptors, Androgen

Figure

• 

  FIG. 1 Scheme of calculation for numbers of AC copies in SRD5A3 gene. For examples, if the value analyzed by GeneMapper program was 189.03, short tandem repeat was the 20 repeats as follow an equation; [(189.03).(91+58)]/2=20.015 (20 repeats).

• 

  FIG. 2 The frequencies of SRD5A3 short tandem repeat between control and patients with prostate cancer. 42.6% of patients with prostate cancer (PCa) had the 20,20 genotype compared to 28.4% of control (χ2=2.97, df=1, p=0.084).

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