Invasive characteristics of human prostatic epithelial cells: understanding the metastatic process

Abstract

Prostate cancer has a predilection to metastasise to the bone marrow stroma (BMS) by an as yet uncharacterised mechanism. We have defined a series of coculture models of invasion, which simulate the blood/BMS boundary and allow the elucidation of the signalling and mechanics of trans-endothelial migration within the complex bone marrow environment. Confocal microscopy shows that prostate epithelial cells bind specifically to bone marrow endothelial-to-endothelial cell junctions and initiate endothelial cell retraction. Trans-endothelial migration proceeds via an epithelial cell pseudopodial process, with complete epithelial migration occurring after 232743 min. Stromal-derived factor-1 (SDF-1)/CXCR4 signalling induced PC-3 to invade across a basement membrane although the level of invasion was 3.5-fold less than invasion towards BMS (P ¼ 0.0007) or bone marrow endothelial cells (P ¼ 0.004). Maximal SDF-1 signalling of invasion was completely inhibited by 10 mM of the SDF-1 inhibitor T140. However, 10 mM T140 only reduced invasion towards BMS and bone marrow endothelial cells by 59% (P ¼ 0.001) and 29% (P ¼ 0.011), respectively. This study highlights the need to examine the potential roles of signalling molecules and/or inhibitors, not just in single-cell models but in coculture models that mimic the complex environment of the bone marrow.

Molecular mechanisms of metastasis in prostate cancer

“…Binding to laminin, type IV and type V collagens is mediated by b 1 and b 4 integrins, whereas bin ding to hyaluronan, fibronectin, type I collagen and cellular migration is mediated by b 1 integrins and CD44 [44,[46][47][48][49]. Understanding the process of secondary site binding and endothelial transmigration in PCa has been facilitated by the development of co-culture models using human BMS and primary PECs and PEC lines [27,39] and the establishment of prostate epithelial colonies in human BMS [50,51]. These models have demonstrated that cell-matrix binding depends fundamentally on the b 1 integrin component of the integrin-binding mechanism.…”

An investigation of the RWPE prostate derived family of cell lines using FTIR spectroscopy

“…Invasion assays were conducted according to Hart et al 16 Basically 1 Â 10 5 cells in 0.25 ml RPMI 1640-0.1% fatty acid free BSA were seeded into cell culture inserts (8 mm pore size) coated with phenol red free MatrigelÔ diluted 1 : 25 with phenol red free RPMI 1640 medium. The inserts were placed in a 24 well plate containing 1 ml of RPMI 1640 (w/o phenol red)-0.1% fatty acid free BSA-10 mM HEPES over tissue culture plastic (TCP) or human bone marrow stroma (BMS).…”

Influence of omega-6 PUFA arachidonic acid and bone marrow adipocytes on metastatic spread from prostate cancer

“…A variation of the invasion co-cultures described by Hart et al (2005) was used. Briefly, FluoroBlok cell culture inserts (8 mm) coated with Matrigel diluted 1 : 25 with phenol red free RPMI 1640 medium, were placed in a 24-well plate containing 1 ml of RPMI 1640 (w/o phenol red)/0.1% fatty acid free (FAF) BSA/ 10 mM HEPES with either tissue culture plastic (TCP), BMS, mBMAd or lipids in the base.…”