(M1130-10-69) Tissue Engineered Human 3D Tumor Model Portfolio Reflecting In Vivo Characteristics for Eficacy Assessment of Preclinical Anti-cancer Therapy In Vitro

Purpose: Preclinical dropout rates in oncology are high (95%) since standard in-vitro systems neglect spatial orientation and stromal components while chimeric animal models can produce inaccurate results for human patients. Thus, more predictive in vitro test methods are needed that mimic not only the tumor itself but also the respective tumor micro environment (TME). For this we have developed a biological xenogeneic matrix that is generated from decellularized porcine jejunal segments. Although the matrix has been successfully employed for lung¹, colorectal², bone, breast³, and pancreatic cancer, the biological nature of the matrix rendering the standardization of the platform challenging. Hence, novel scaffold materials are needed that allow both for an effective scale-up while maintaining the predictive capacity of the models.

Methods: Based on a refined electrospinning process using porogens in addition to the standard electrospinning process, a method was developed to generate synthetic scaffolds with highly porous fibrous structures and enhanced fiber-to-fiber distances⁴. Since this approach allows for cell migration, matrix remodeling, and ECM synthesis, the scaffold provides an ideal platform for the generation of soft tissue equivalents. Within this study we compared the capacity of the novel material platform to generate tumor models to the previous established biological matrix.

Results: Following the establishment of different epithelial models such as skin, cornea and airway, melanoma models were generated on the novel scaffold material (see figure 1) display an initiative step towards the preclinical efficacy assessment of anti-melanoma-therapies. We succeeded to create human melanoma models of various complexity and different tumor stages reflecting not only the physiological but also correlating with the in vivo situation. The formed melanoma could be detected physiologically located at the basal layer of the well stratified epidermis. Moreover, the 3D melanoma model harbours not only the tumor itself but also partly the respective microenvironment, in which the melanomagenesis takes place. The novel scaffold material depicts a methodology that allows the tumor to mature within the respective TME. In following studies, the approach was successfully transferred to other tumor entities e.g. for breast, bone and pancreatic cancer.

Conclusion: The novel scaffold provides an industrial applicable platform for the generation of in vitro tumor models comparable to a previously established biological matrix.

References: 1) Göttlich C, Kunz M et al. Dandekar T, Dandekar G. A combined tissue-engineered/in silico signature tool patient stratification in lung cancer. Mol Oncol. 2018 Aug;12(8):1264-1285.
2) Nietzer, S.L., Baur, F. et al. Gasser M, Waaga-Gasser, A.M. Walles, H and Dandekar G. Tissue Eng Part C Methods. 2016 May 3. 22(7): 621-35.
3) Wallstabe L, Göttlich C, Nelke LC, Kühnemundt J et al. Walles H, Dandekar G, Nietzer SL, Hudecek M. ROR1-CAR T cells are effective against lung and breast cancer in advanced microphysiologic 3D tumormodels. JCI Insight. 2019 Sep 19;4(18).
4) Weigel T, Malkmus C, Weigel V, Wußmann M, Berger C, Brennecke J, Groeber-Becker F, Hansmann J. Fully Synthetic 3D Fibrous Scaffolds for Stromal Tissues-Replacement of Animal-Derived Scaffold Materials Demonstrated by Multilayered Skin. Adv Mater. 2022 Mar;34(10):e2106780

Acknowledgements: Disclosure Statement: The authors declare no conflict of interest.

Figure 1: Characterization of epidermal-dermal melanoma equivalents based on fully synthetic PA6 fibers. (A) Hematoxylin and eosin staining of cross-sections of epidermal-dermal healthy skin equivalents and melanoma full-thickness skin models based on the electrospun PA6 fibers ((m)FTSEPA6, (melanoma) full thickness skin equivalent on PA6 basis), and an in situ melanoma. SC = stratum corneum, SG = stratum granulosum, SS = stratum spinosum, SB = stratum basale, D = dermis. Melanoma nests are indicated by arrowheads. Scale bar corresponds to 100 µm. (B) Immunofluorescence staining of mFTSEPA6 for the keratinocyte marker cytokeratin 14 (CK14, turquoise) in combination with the melanoma marker HMB-45 (green), the extracellular matrix (ECM) marker collagen I (ColI, green), and the fibroblast marker vimentin (red). The scale bar corresponds to 100 μm.