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Updated: Aug 13, 2026

Identification, Histological Characterization, and Dissection of Mouse Prostate Lobes for In Vitro 3D Spheroid Culture Models
Published on: September 18, 2018
[Importance of heterotrimeric G proteins in prostate cancer molecular biology]
J C Prieto Villapun1, R M Solano Haro, M J Carmena Sierra
1Departamento de Bioquímica y Biologia Molecular, Universidad de Alcald, Alcalá de Henares.
Objective:
To deep in the knowledge of the involvement of G-protein alphas and alphai subunits in human prostate cancer.
Methods:
Prostate tissue from 9 patients undergoing radical prostatectomy for prostate cancer and 5 controls undergoing cystoprostatectomy for bladder carcinoma. G-protein alphas and alphai subunits were studied for expression (mRNA by RT-PCR and protein by Western-blot), functionality (adenylyl cyclase activity, AC) and possibility of mutations (analysis with restriction enzymes and cDNA sequentiation).
Results:
At mRNA level, the expression of alphas, alphai1, alphai2 y alphai3 was detected in healthy and cancerous tissues. At protein level, the expression of alphas y alphai1,2 diminished (25% and 40%, respectively) in prostate cancer. The expression of alphai3/0 also diminished, whereas that of beta subunit was not modified. Basal AC activity in adenocarcinoma membranes was 40% inferior to the control. Digestion with restriction enzymes Eag I or AlwN I did not allow to locate mutations in alphas. However, digestion at alphai2 level with BstU I enzyme served to observe a change of Gln205 (CAG triplet) to Pro (CCG).
Conclusions:
The functionality and expression of heterotrimeric G proteins are selectively modified in human prostate adenocarcinoma, occurring in addition some punctual mutation. The observed substitution of Gln205 by Pro may result in a low GTPase activity for alphai2 that, therefore, is stabilized in its active form.
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