Polystyrene-Based Slippery Surfaces Enable the Generation and Easy Retrieval of Tumor Spheroids

Abstract

Multicellular tumor spheroids are the most well-characterized organotypic models for cancer research. Generally, scaffold-based and scaffold-free techniques are widely used for culturing spheroids. In scaffold-free techniques, the hanging drop (HD) method is a more versatile technique, but the retrieval of three-dimensional (3D) cell spheroids in the hanging drop method is usually labor-intensive. We developed oil-coated polystyrene nanofiber-based reusable slippery surfaces for the generation and easy retrieval of 3D spheroids. The developed slippery surfaces facilitated the rolling and gliding of the cell medium drops as well as holding the hydrophilic drops for more than 72 h by the virtue of surface tension as in the hanging drop method. In this study, polystyrene nanofibers were developed by the facile technique of electrospinning and the morphological evaluation was performed by scanning electron microscopy (SEM) and cryo-FESEM. We modeled the retrieval process of 3D spheroids with the ingredients of 3D spheroid generation, such as water, cell culture media, collagen, and hyaluronic acid solution, demonstrating the faster and easy retrieval of 3D spheroids within a few seconds. We created MCF-7 spheroids as a proof of concept with a developed slippery surface. 3D spheroids were characterized for their size, homogeneity, reactive oxygen species, proliferative marker (Ki-67), and hypoxic inducing factor 1ά (HIF-1ά). These 3D tumor spheroids were further tested for evaluating the cellular toxicity of the doxorubicin drug. Hence, the proposed slippery surfaces demonstrated the potential alternative of culturing 3D tumor spheroids with an easy retrieval process with intact 3D spheroids.

High throughput generating stable spheroids with tip‐refill wafer

“…The WCA value of TrW is 86.8° (Figure S4), contributeing to the stability of the droplets, as indicated by previous studies. [ 18 ] Additionally, the 1 mm thickness of the TrW played a role in stabilizing the hanging drops, as previous studies have shown that the thickness of the hole can create a micro‐ring structure that aids in droplet stabilization. [ 15,16 ]…”

Mechanistic Investigation of Thiazole-Based Pyruvate Kinase M2 Inhibitor Causing Tumor Regression in Triple-Negative Breast Cancer

“…It has been observed that there is a difference in cytotoxicity, apoptosis, and cell cycle arrest of 7d between 2D and 3D systems. The 2D system consists of a monolayer, and the 3D system is a tumor spheroid. , There is a direct exposure of the cells to 7d in the case of the 2D system causing higher mortality and low IC 50 value when compared to the 3D system. In a 3D system, molecules need to cross the cell culture media effectively to reach the site of action.…”

“…The plate was cultivated for 10 days at 37 °C with 5% CO 2 . The developed cell spheroids were recovered by tilting the device to a 45° angle to the tissue culture wells filled with culture medium at each time point . The same procedure was also followed for the cytotoxicity assay as that of the 2D counterpart.…”

Biomimetic Lipid-polymer composite membrane model to study Permeability through Cornea

“…The final PC content in the membrane was determined by taking the membrane weight before and after the entrapment of PC. (Pulugu et al, 2022) These dried membranes were then used for the permeation studies of the model drug.…”

“…The final PC content in the membrane was determined by taking the membrane weight before and after the entrapment of PC. (Pulugu et al, 2022) These dried membranes were then used for the permeation studies of the model drug. Samples were initially sputter coated with gold to obtain SEM images and were imaged at the accelerating voltage of 5 KV.…”