Abstract
Timely and spatially-regulated injectable hydrogels, able to suppress growing tumors in response to conformational transitions of proteins, are of great interest in cancer research and treatment. Herein, we report rapidly responsive silk fibroin (SF) hydrogels formed by a horseradish peroxidase (HRP) crosslinking reaction at physiological conditions, and demonstrate their use as an artificial biomimetic three-dimensional (3D) matrix. The proposed SF hydrogels presented a viscoelastic nature of injectable hydrogels and spontaneous conformational changes from random coil to β-sheet conformation under physiological conditions. A human neuronal glioblastoma (U251) cell line was used for screening cell encapsulation and in vitro evaluation within the SF hydrogels. The transparent random coil SF hydrogels promoted cell viability and proliferation up to 10 days of culturing, while the crystalline SF hydrogels converted into β-sheet structure induced the formation of TUNEL-positive apoptotic cells. Therefore, this work provides a powerful tool for the investigation of the microenvironment on the programed tumor cells death, by using rapidly responsive SF hydrogels as 3D in vitro tumor models.
Highlights
Hydrogels are hydrophilic networks with high capacity to absorb and retain high quantities of water, while keeping its original structure [1]
silk fibroin (SF) hydrogels immersed in phosphate buffer saline solution (PBS) solution at 37 ̊C for 14 days presented a transparent morphology over the first 7 days, becoming completely opaque after 10 days of incubation (Fig 1b) [20]
The present work demonstrates the formation of stimuli-responsive enzymatically crosslinked SF hydrogels that undergo a spontaneous conformational transition from random coil to βsheet at physiological conditions
Summary
Hydrogels are hydrophilic networks with high capacity to absorb and retain high quantities of water, while keeping its original structure [1]. Stimuli-responsive hydrogels, are more appealing for cell encapsulation in a three-dimensional (3D) microenvironment, drug delivery systems and tissue engineering (TE) scaffolding. Silk fibroin hydrogels and tumor cells death. An internal R&D grant of Anasys Instruments Corp provided support in the form of salary for author AR, but did not have any additional role in the study design, decision to publish, or preparation of the manuscript. The specific role of this author is articulated in the “author contributions” section.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
