Deoxycholic acid-modified microporous SiO2 nanofibers mimicking colorectal microenvironment to optimize radiotherapy-chemotherapy combined therapy

Radiotherapy and chemotherapy remain the main therapeutics for colorectal cancer. However, due to their inevitable side effects on nomal tissues, it is necessary to evaluate the toxicity of radio-/chemotherapy regimens. The newly developedin vitrohigh throughput strategy is promising for these assessments. Nevertheless, the currently monolayer culture condition adopted in the preclinical screening processesin vitrohas been proved not so efficient asin vivosince its poor physiological similarity toin vivomicroenvironment. Herein, we fabricated microporous SiO2nanofiber mats and further bioactivated with deoxycholic acid (DCA) to mimic the chemical signals in the colorectal cancer microenvironment forin vitroregimen assessment of radiotherapy and chemotherapy. The colorectal cancer cells contacted with the DCA-modified SiO2nanofiber (SiO2-DCA NF) mats spatially, and the human intestinal epithelial cell on SiO2-DCA NF mats exhibited better x-ray and cisplatin tolerance. The distinguishable irradiation and drug tolerance of cells on SiO2-DCA NF mats indicated that the actual microenvironment of intestine might instruct colorectal cancer differently compared with the common biological experiments. The presented DCA-modified microporous SiO2nanofibrous mats endowing a better mimicry of colorectal micro-environment, would provide a promising platform forin vitroassessment of radio-/chemotherapy regimens.