Abstract 189: Stromal primary cultures from advanced human prostate cancer obtained from needle biopsies revealed distinctive gene expression pattern and functionality
Authors: Cerda-Infante Javier , Conejeros Paola F. , Coronado Romina A. , Francisco Ignacio F. San , Smith Gary J. , Godoy Alejandro S. , Montecinos Viviana P. 
Published: May 2015

Introduction: Although several pieces of data indicate a critical role of the carcinoma associated stroma (CAS) in the progression of prostate cancer (CaP), little is known about the specific mechanisms by which CAS contributes to the evolution of the castration-recurrent phenotype in locally advanced/metastatic CaP patients. The main challenge in this area has been the ability to obtain primary cultures of human prostate stroma cells (HPSCs) from locally advanced or metastatic CaP, because therapeutic surgery is not a feasible option for these patients. The aim of this study was to standardize a methodology to obtain primary cultures of HPSCs from from needle biopsies of the primary tumor of advanced CaP and to investigate whether HPSCs from different histological/pathological origins have distinct transcriptional programs.

Material and Methods: Primary cultures of HPSCs were obtained from explants of needle biopsies from the peripheral zone of primary tumor of advanced/metastatic CaP patients (T3/T4) or from peripheral zone from patients without evidence of neoplasia (BAS). HPSCs were characterized using gene expression profile (Illumina), qPCR, immunocytochemistry and western blot. The phenotypic alterations were analyzed using the stroma cell markers calponin, vimentin, pro-collagen and α-smooth muscle actin. Migration and invasion assays using co-cultures of stroma-epithelium were utilize to evaluate the functional role of CAS.

Results: Analysis of primary cultures of HPSCs from benign and locally advanced and/or metastatic CaP tissue explants revealed that CAS are a heterogeneous population of cells, typified by the increment of myofibroblasts/fibroblasts ratio and collagen production. The proliferation rate and doubling time was significantly higher in CAS compared to BAS. Analysis of gene expression profile revealed that CAS exhibited a unique transcriptional program, up-regulating genes involved in cell proliferation migration and cell adhesion. Furthermore, migration and invasion assays using co-cultures of stroma-epithelium demonstrated that HPSCs from CAS, but not BAS, contributed to the invasive potential of CaP cell lines.

Discussion: Our studies demonstrated that CAS from the primary tumor of advanced/metastatic CaP patients was intrinsically different from the stroma associated to non-invasive CaP. Accordingly, primary cultures of HPSCs from primary tumors of metastatic patients provide an invaluable tool for modeling the effect of perturbation of the prostate tissue microenvironment during the progression of CaP.

Citation Format: Javier Cerda-Infante, Paola F. Conejeros, Romina A. Coronado, Ignacio F. San Francisco, Gary J. Smith, Alejandro S. Godoy, Viviana P. Montecinos. Stromal primary cultures from advanced human prostate cancer obtained from needle biopsies revealed distinctive gene expression pattern and functionality. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 189. doi:10.1158/1538-7445.AM2014-189