Effects of FGFR inhibitors TKI258, BGJ398 and AZD4547 on breast cancer cells in 2D, 3D and tissue explant cultures.

PURPOSE: Fibroblast growth factor receptors (FGFR) and pathways are important players in breast cancer (BC) development. They are commonly altered, and BCs exhibiting FGFR gene amplification are currently being studied for drug development. Here, we aimed to compare the effects of three FGFR inhibitors (FGFRis), i.e., non-selective TKI258 and selective BGJ398 and AZD4547, on different BC-derived cell lines (BCCs) and primary tissues. METHODS: The human BCCs MCF-7 and MDA-MB-231(SA) (wild-type FGFR) and MFM223 (amplified FGFR1 and FGFR2) were analyzed for FGFR expression using qRT-PCR, and the effects of FGFRis on FGFR signaling by Western blotting. The effects of FGFRis on proliferation, viability, migration and invasion of BCCs were assessed in 2D cultures using live-cell imaging, and in 3D cultures using phenotypic analysis of organoids. To study radio-sensitization, FGFRi treatment was combined with irradiation. Patient-derived BC samples were treated with FGFRis in explant cultures and immunostained for Ki67 and cleaved caspase 3. RESULTS: We found that all FGFRis tested decreased the growth and viability of BC cells in 2D and 3D cultures. BGJ398 and AZD4547 were found to be potent at low concentrations in FGFR-amplified MFM233 cells, whereas higher concentrations were required in non-amplified MCF7 and MDA-MB-231(SA) cells. TKI258 inhibited the migration and invasion, whereas BGJ398 and AZD4547 only inhibited the invasion of MDA-MB-231(SA) cells. FGFRi treatment of MCF7 and MFM223 cells enhanced the inhibitory effect of radiotherapy, but this effect was not observed in MDA-MB-231(SA) cells. FGFRi-treated primary BC explants with moderate FGFR levels showed a tendency towards decreased proliferation and increased apoptosis. CONCLUSIONS: Our results indicate that, besides targeting FGFR-amplified BCs with selective FGFRis, also BCs without FGFR amplification/activation may benefit from FGFRi-treatment. Combination with other treatment modalities, such as radiotherapy, may allow the use of FGFRis at relatively low concentrations and, thereby, contribute to better BC treatment outcomes.

Proteinases in cutaneous wound healing.

Cutaneous wound healing is a complex and highly coordinated process where a number of different cell types participate to renew the damaged tissue under the strict regulation of soluble and insoluble factors. One of the most versatile processes involved in wound repair is proteolysis. During cell migration, proteins of extracellular matrix are cleaved, often creating biologically active cleavage products, and proteolysis of cellular contacts leads to increased cell motility and division. Moreover, proteases activate various growth factors and other proteases in wound and regulate growth factor signaling by shedding growth factor receptors on cell surface. Normally, proteolysis is strictly controlled, and changes in protease activity are associated with alterations in wound closure and scar formation. Here, we present the current view on the role of metalloproteinases and the plasmin-plasminogen system in normal and aberrant cutaneous wound repair and discuss their role as potential therapeutic targets for chronic ulcers or fibrotic scars.

Extended release of adenovirus from silica implants in vitro and in vivo.

Despite promising preclinical results, the clinical benefits of cancer gene therapy have been modest heretofore. The main obstacle continues to be the level and persistence of gene delivery to sufficiently large areas of the tumor. One approach for overcoming this might entail extended local virus release. We studied the utility of silica gel monoliths for delivery of adenovirus to advanced orthotopic gastric and pancreatic cancer tumors. Initially, the biochemical properties of the silica-virus matrix were studied and nearly linear release as a function of time was detected. Virus stayed infective for weeks at +37 degrees C and months at +4 degrees C, which may facilitate storage and distribution. In vivo, extended release of functional replication deficient and also replication-competent, capsid-modified oncolytic viruses was seen. Treatment of mice with pancreatic cancer doubled their survival (P<0.001). Also, silica gel-based delivery slowed the development of antiadenovirus antibodies.