Electrospun fibrous platforms as 3D in vitro model for screening chemotherapeutic drug effect in tissue regeneration and cancer therapy

Introduction: All tissues - i.e., healthy and cancerous ones - are composed of cells regulating body processes, maintenance and wound healing, and the extracellular matrix (ECM) - a chemically and structurally complex matter able to dynamically influence phenotypic/not phenotypic cell involved in regeneration and degeneration processes[1]. Recently, much more attention has been referred to the definition of 3D in vitro tissue models able to reproduce ECM functionalities, by controlling molecular transport for an optimal administration of biochemical signals (i.e., growth factors, drugs) to guide cells fate in different ways[2]. In this context, engineered scaffolds may provide a support matrix with ECM-like physical/structural properties suitable to in vitro reproduce all the main functionalities that healthy tissue or tumor microenvironment exert in vivo[3]. In particular, electrospinning is emerging as an interesting micro/nano-fabrication technique to develop 3D platforms to predict the effect of chemotherapeutic drugs on in vitro cell activities. Here, we investigate how Poly-?-caprolactone (PCL) electrospun scaffolds may influence the behavior of hMSC or tumor cells (i.e., hepatocarcinoma) in response to different chemotherapeutic molecules administration in order to validate their use as in vitro model for tissue engineering and cancer therapy. Materials and Methods: PCL fibers were produced by electrospinning technique, dissolving the polymer in chloroform (0.33 g/ml). hMSC and Hep G2 cells were seeded onto PCL electrospun fibers. Cell survival was analyzed by MTT assay. In particular, hMSC differentiation was analyzed by YIP-1B expression in presence or in absence of 5-AZA (1 and 5?M). Meanwhile, Hep G2 proliferation was evaluated by Brdu ELISA in the presence of doxorubicin (0.4 and 0.8 ?M). In both cases, qualitative cell attachment was observed by FESEM analysis. Results and Discussion: We demonstrated that PCL fibers did not exert a cytotoxic effect on hMSCs, whereas they may reduce Hep G2 cell viability compared to plate control. SEM clearly showed hMSC and Hep G2 adhesion onto electrospun PCL fibers. Brdu assay suggested that PCL without doxorubicin significantly inhibited Hep G2 proliferation compared to plate control, but did not improve the effect of doxorubicin on Hep G2 proliferation. Contrariwise, in the case of hMSCs treated with 5-AZA, PCL fibers significantly increased YIP-1B expression - as index of myogenic differentiation, compared to plate control. Conclusion: We demonstrate that 3D fibrous network with the structural organization of ECM collagen fibers may influence interactions among cells mediated by chemotherapeutic drugs. This may open new interesting routes in drug administration to minimize side effects while preserving therapeutic benefits, thus concurring to the definition of more efficacious preclinical models for tissue regeneration/degeneration.