Reconstructing skin cancers using animal models

The influence of viscosity of hydrogels on the spreading and migration of cells in 3D bioprinted skin cancer models

Various in vitro three-dimensional (3D) tissue culture models of human and diseased skin exist. Nevertheless, there is still room for the development and improvement of 3D bioprinted skin cancer models. The need for reproducible bioprinting methods, cell samples, biomaterial inks, and bioinks is becoming increasingly important. The influence of the viscosity of hydrogels on the spreading and migration of most types of cancer cells is well studied. There are however limited studies on the influence of viscosity on the spreading and migration of cells in 3D bioprinted skin cancer models. In this review, we will outline the importance of studying the various types of skin cancers by using 3D cell culture models. We will provide an overview of the advantages and disadvantages of the various 3D bioprinting technologies. We will emphasize how the viscosity of hydrogels relates to the spreading and migration of cancer cells. Lastly, we will give an overview of the specific studies on cell migration and spreading in 3D bioprinted skin cancer models.

Research Techniques Made Simple: Preclinical Development of Combination Antitumor Targeted Therapies in Dermatology

The identification and application of targeted therapies that inhibit critical pathways in malignant cells have shown tremendous promise for improving clinical outcomes for patients with advanced cutaneous malignancies. However, tumor cell heterogeneity, development of drug resistance, and risks of off-target effects remain barriers to prolonged remission and definitive cure. Herein, we describe the potential that combinations of antitumor targeted agents may offer in overcoming these challenges and detail techniques whereby promising combination regimens can be identified and further evaluated preclinically. Cancer cell lines and primary patient-derived malignant cells can be utilized to perform dose-response screenings in vitro for individual targeted agents before moving toward the evaluation of potential synergistic combinations. Mathematical analyses, including the Chou-Talalay method, determine combination indices and Hill slopes that permit relative comparisons among various drug combinations by quantification of synergistic activities. Further preclinical in vivo evaluation of promising single versus combination regimens may be studied in relevant mouse models of cutaneous malignancy. Ultimately, the formulation of combination targeted therapy regimens may be more broadly effective and less toxic, helping to better inform clinical trial design and prioritization.