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Updated: Apr 12, 2026
miRNA Expression Analyses in Prostate Cancer Clinical Tissues
Published on: September 8, 2015
Changes of protein expression in prostate cancer having lost its androgen sensitivity
Gergely Bánfi1, Ivett Teleki, Péter Nyirády
1Department of Urology, Semmelweis University, Budapest, Hungary, banfigergely@hotmail.com.
Objective:
The majority of prostate cancers require androgen hormones for growth, and androgen ablation is an important part of the systemic treatment of advanced prostate cancer. Nevertheless, most of these cancers eventually relapse as they become less sensitive to androgen ablation and anti-androgen treatment. Elucidating the molecular events that are responsible for the conversion of androgen-sensitive cancers to androgen-refractory tumors may reveal new therapeutic opportunities.
Methods:
In the present study, we investigated nine androgen-sensitive and nine androgen-refractory prostate cancer samples to evaluate the expression levels of 10 selected proteins that have been implicated in oncogenesis and cancer progression.
Results:
Our immunohistochemical data show that three of the investigated proteins (i.e., minichromosome maintenance-2, methylguanine-DNA methyltransferase, and androgen receptor) are expressed at significantly different levels in the androgen-refractory cancer samples than in the androgen-sensitive tumors, whereas the expression levels of the seven other studied proteins (i.e., β-catenin, p27, p21, p16, Ki67, hypoxia-inducible factor 1 alpha, and geminin) are not significantly different regarding the two groups.
Conclusions:
Our data suggest that the increased expression of minichromosome maintenance-2 and decreased expression of methylguanine-DNA methyltransferase related to androgen receptor are indicative of the androgen-refractory stage in prostate cancer. Further studies are required to determine whether these expression changes play a causative role in the transition of androgen-sensitive to androgen-refractory prostate cancer.
Insights
Prostate cancer can become resistant to hormone therapy. Researchers found that changes in minichromosome maintenance-2 and methylguanine-DNA methyltransferase expression indicate this androgen-refractory stage.
Area of Science:
- Oncology
- Molecular Biology
- Biochemistry
Background:
- Prostate cancer growth is often driven by androgen hormones.
- Androgen ablation is a standard treatment for advanced prostate cancer.
- Cancers frequently develop resistance to androgen ablation, leading to relapse.
Purpose of the Study:
- To identify molecular markers associated with the transition from androgen-sensitive to androgen-refractory prostate cancer.
- To investigate the differential expression of proteins involved in oncogenesis and cancer progression between sensitive and refractory tumors.
Main Methods:
- Comparative immunohistochemical analysis of protein expression.
- Study included nine androgen-sensitive and nine androgen-refractory prostate cancer samples.
- Evaluated expression levels of ten selected proteins implicated in cancer.
Main Results:
- Significantly different expression levels were observed for minichromosome maintenance-2, methylguanine-DNA methyltransferase, and androgen receptor.
- Minichromosome maintenance-2 was upregulated, while methylguanine-DNA methyltransferase was downregulated in refractory tumors.
- Expression levels of seven other proteins (β-catenin, p27, p21, p16, Ki67, HIF-1α, geminin) did not differ significantly.
Conclusions:
- Increased minichromosome maintenance-2 and decreased methylguanine-DNA methyltransferase expression correlate with the androgen-refractory state in prostate cancer.
- These expression changes, particularly in relation to androgen receptor, may serve as indicators of treatment resistance.
- Further research is needed to confirm a causal role in the progression to androgen-refractory prostate cancer.
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