library_construction_protocol: After seven days of culture 'Collagen' or "Mineralized Collagen' cultured MDA-MB-231 cells were harvested with collagenase Type-I. RNA was isolated from each condition using an RNA isolation kit (Qiagen, US) according to the manufacturer's protocols (n = 4). Illumina TruSeq RNA stranded kit (Illumina, US) was used for library preparation, and samples were sequenced as 1 × 86 bp single-end reads on the NextSeq500 (Illumina, US), yielding on average 42 M reads per sample.