Tumour-stroma interactions between metastatic prostate cancer cells and fibroblasts

Abstract

Abstract.Previous work has shown the importance of tumourstroma interactions for prostate cancer development at the primary site. The aim of the present study was to find out whether evidence can be found for a tumour-stroma crosstalk also between metastatic prostate cancer cell lines and non-prostatic stromal fibroblasts which are encountered by metastatic cells at most sites. We addressed this issue in cell culture systems using 3 metastatic human prostate cancer cell lines (LnCaP, PC-3 and DU-145) on the one hand, and a human fibroblast line (HFF, human foreskin fibroblasts) on the other. We incubated fibroblasts with tumour cell-and tumour cells with fibroblast-conditioned media and evaluated several parameters important for the establishment of metastases such as cell proliferation, migration and expression of matrix degrading proteases. We also determined in the conditioned media the concentrations of several growth factors and cytokines which might be responsible for the observed effects. We found that media conditioned by all 3 metastatic prostate cancer cell lines stimulated fibroblast proliferation which corresponds to fibrous stroma induction in vivo. DU-145 cell conditioned media induced in fibroblasts expression of mmp-1 mRNA known to be important for tumour invasion. ELISA assays revealed that tumour cells secrete bFGF, PDGF and TNF· known to stimulate fibroblast proliferation and/or MMP-1 expression. Cultivation of DU-145 carcinoma cells in fibroblast conditioned medium resulted in an enhanced proliferation and anchorage-independent growth of this cell line in soft agar. Fibroblast conditioned medium also increased migration of PC-3 cells in the wound assay and slightly augmented mmp-1 expression. KGF (able to stimulate proliferation of normal and neoplastic prostate epithelial cells) was secreted by fibroblasts at higher concentrations than by all 3 tumour cell lines. In addition, fibroblasts secreted TNF·, bFGF, PDGF, HGF and also VEGF, the most important factor for tumour vascularization. Our results provide evidence that tumour-stroma interactions do not only exist at the primary site but also between metastatic prostate cancer cell lines and their fibroblastic microenvironment. These interactions, which are mediated through secreted factors, affect several steps of the metastatic cascade including proliferation, anchorage-independent growth, migration and the secretion of matrix-degrading proteases.

Control of tumor and microenvironment cross-talk by miR-15a and miR-16 in prostate cancer

“…Another early prostate cancer cell line, CAHPV10, reduced its migratory capacity in miRNA CM as compared with TW CM (Supplementary Figure 2a). Likewise, metastatic PC3 cells reduced their motility capacity when maintained for 24 h in miR-15/16 CM, such as demonstrated by scratch-wound assay (Supplementary Figure 2b) (Kaminski et al, 2006). Moreover, the metastasis-derived prostate cancer cell line DU145 was maintained in culture with TW or miR-15/16 CM and analyzed after 24 h by bromodeoxyuridine incorporation assay.…”

Origin of carcinoma associated fibroblasts

“…[115][116][117][118] The fibroblast response is hardwired in the genome as part of the cancer's resemblance to a chronic wound, aiming at support of epithelial cell survival and expansion. [119][120][121][122][123][124][125][126][127][128] In addition to parsimony, this hypothesis offers clear predictions to scientifically test against corresponding null hypotheses; (1) That co-culture of cancer cells with normal fibroblasts will induce expression of CAF-specific genes in the fibroblasts, [63][64][65][66][67][68][69][70][71] [63][64][65][66][67][68][69][70][71] Many of the genes shown to be activated in these co-cultures are known markers of CAFs in vivo, such as MMP1, MMP3, collagens, TNC, etc. Evidence that this reciprocal interaction promotes cancer includes the anti-cancer effect of Imatinib, on carcinoma animal models.…”

Tumor-host interactions: the role of inflammation

“…Tumor cell-conditioned culture media-stimulated Wbroblasts are reported to display a phenotype reminiscent of carcinoma-associated Wbroblasts (CAFs), secreting keratinocyte growth factor (KGF), tumor necrosis factor-(TNF ), basic Wbroblast growth factor (bFGF), platelet derived growth factor (PDGF), hepatocyte growth factor (HGF) and vascular endothelial growth factor (VEGF), that can in turn stimulate proliferation of both normal and neoplastic cells. Conversely, Wbroblast conditioned culture medium can enhance proliferation and anchorage-independent growth of some carcinoma cell lines and facilitates migration of others (Kaminski et al 2006). CAFs have also been reported to stimulate transformation and progression of initiated prostate epithelial cells (Olumi et al 1999).…”

“…Incubation of normal human Wbroblasts with culture media conditioned by metastatic prostate cancer cell lines illustrates the importance of the eVect of tumor cell-derived factors on the host tissue stroma (Kaminski et al 2006). Tumor cell-conditioned culture media-stimulated Wbroblasts are reported to display a phenotype reminiscent of carcinoma-associated Wbroblasts (CAFs), secreting keratinocyte growth factor (KGF), tumor necrosis factor-(TNF ), basic Wbroblast growth factor (bFGF), platelet derived growth factor (PDGF), hepatocyte growth factor (HGF) and vascular endothelial growth factor (VEGF), that can in turn stimulate proliferation of both normal and neoplastic cells.…”